Image display device and method for driving image display device

The present invention relates to an image display device having a function of detecting the position of an object and the like, and a method of driving the image display device.

Conventionally, there has been known a technique for detecting the position of an object that is in contact with or is close to a display device. Among them, a display device equipped with a touch panel is a typical and widely used technology.

There are various types of touch panels, but one that is widely used is a type that detects capacitance. This type captures changes in the surface charge of the panel by touching the touch panel with a finger, thereby detecting the position of an object or the like. As a result, the user can operate it intuitively.

Further, in recent years, various techniques have been proposed that enable intuitive operation by detecting the position of an object with respect to a display device without providing these touch panels.

For example, in Patent Document 1, an infrared light emitting element and a light receiving element such as infrared rays are arranged at one end of a flat pad on which a finger can be moved, and pointer control can be performed only by moving the finger. A finger input pointer device is disclosed.<patcit num="1"><text>Japanese Unexamined Patent Publication No. 11-149348</text></patcit>

<p> However, this technology requires an input device or the like to be provided separately from the display device, and the cost of the product increases due to the increase in the number of parts, and the operation is more intuitive than the display device equipped with a touch panel. There was a problem that it could not be done.</p><p> Further, with respect to a display device provided with a touch panel, the number of parts increases and the cost of the product increases by providing the touch panel on the display screen. Another problem is that the light from the display screen changes when it passes through the touch panel, causing deterioration in image quality.</p><p> Furthermore, in the case of the above-mentioned commonly used touch panel that detects capacitance, only one point on the display screen can be detected at the same time, which is not always convenient for the user. There was a problem that I couldn't say it.</p><p> That is, these conventional techniques have a problem that it is difficult to detect the position of an object or the like without deteriorating the image quality with a simple structure while ensuring convenience.</p><p> The present invention has been made in view of such problems, and an object of the present invention is to provide an image display device capable of detecting the position of an object or the like with a simple structure without deteriorating image quality while ensuring convenience. The purpose of the present invention is to provide a method for driving an image display device.</p>

<p> The image display device of the present invention has a plurality of light emitting / receiving elements each having a light emitting function and a light receiving function, a light emitting driving means for driving the light emitting / receiving element based on the image data, and light emitting light based on the image data. From the light-receiving driving means for driving the other light-emitting and light-receiving elements and the other light-emitting and light-receiving elements so that the other light-emitting and light-receiving elements receive the light emitted from the one light-emitting and light-receiving element and reflected by the object to be detected. It is provided with a detection means for detecting an object to be detected based on the obtained received light signal.</p><p> In the driving method of the image display device of the present invention, a plurality of light emitting and receiving elements, each of which has both a light emitting function and a light receiving function, are arranged, the light emitting and receiving elements are driven to emit light based on the image data, and light is emitted based on the image data. The other light emitting / receiving element is driven to receive the light emitted from one light emitting / receiving element and reflected by the object to be detected, and the light received from the other light emitting / receiving element is received. The object to be detected is detected based on the signal.</p><p> In the image display device and the driving method of the image display device of the present invention, the light emitting / receiving element emits light based on the image data. Another light emitting / receiving element emits light from the light emitting / receiving element, receives the light reflected by the object to be detected, and outputs a light receiving signal. The object to be detected is detected based on the received signal. Even when a plurality of detection target objects are arranged at the same time, it is possible to configure the detection target objects to be detected based on the received light signal. Here, "arranged at the same time" means, for example, a situation in which a plurality of fingers are in contact with or close to each other on the display unit of the image display device.</p><p> In addition, when a threshold value is set according to the properties of the object to be detected or the purpose or accuracy of the detection, the received signal is compared with the set threshold value for these purposes. The object to be detected is detected in the manner corresponding to the above. Here, the "property of the object to be detected" means, for example, the size and surface state (reflectivity, color, roughness, etc.) of the object, and the "purpose of detection" is, for example, the object. It means position detection, object size detection, object color detection, etc., and "detection accuracy" means detection resolution.</p><p> In addition, the intensity of the ambient light existing in the surroundings is obtained based on the received signal obtained when the black display is performed when the object to be detected is not close to the light emitting and receiving element, and the influence of the ambient light is taken into consideration. When the detection target object is detected, the detection target object is detected regardless of the influence of the ambient light. Here, the "black display" means a display in which all the light emitting and receiving elements included in the image display device emit the lowest brightness, and the "ambient light" means, for example, sunlight or light from an indoor light. , Means the light emitted from the surroundings.</p><p> Further, a part of the input image data is replaced with the mark data for displaying a predetermined mark, the image data is synthesized, and the light emitted from the light emitting / receiving element according to the mark data is the position corresponding to the light emitting / receiving element. When the light is received by another light emitting / receiving element, it is detected whether or not the object to be detected has approached this mark on the display. In this case, it is possible to move this mark during image display, and it is also possible to configure the mark to move according to the movement of the pattern, for example. Here, the "input image data" means the raw image data before composition as it is input to the image display device, and the "mark data" means, for example, the shape, brightness, and brightness of any figure or character. It means a sign represented by a color or the like.</p><p> Here, for example, these plurality of light emitting / receiving elements are arranged in a matrix, and the light emitting / receiving elements are driven so as to perform a line-sequential light emitting operation, and at the same time, the light emitting / receiving elements other than the light emitting / receiving elements during light emission are synchronized with this. May be configured to be driven so as to perform a light receiving operation in line sequence. Here, the matrix means a state in which a plurality of light emitting and receiving elements are arranged in a matrix in the horizontal line direction and the vertical line direction of the screen over the entire display unit of the image display device, and each of the arranged elements is arranged in a matrix. Elements are called pixels. The "line-sequential light-emitting operation" and the "line-sequential light-receiving operation" are operations in which the light-emitting light-receiving elements included in each pixel of a certain horizontal line sequentially emit light and receive light for each horizontal line. This means that by performing this over the entire display unit of the image display device, it is possible to display image data for one screen and receive light for each pixel for one screen.</p>

<p> According to the image display device and the driving method of the image display device of the present invention, a plurality of light emitting and receiving elements, each of which has both a light emitting function and a light receiving function, are provided, and the light emitting and receiving elements are driven to emit light based on the image data. The other light emitting / receiving element is driven to receive the light emitted from the light emitting / receiving element and reflected by the object to be detected so that the other light emitting / receiving element receives the light, and the light is detected based on the light receiving signal obtained from the other light emitting / receiving element. Since the target object is detected, it is possible to detect the position of the object with a simple structure without deteriorating the image quality while ensuring convenience.</p>

Hereinafter, the best mode for carrying out the present invention (hereinafter, simply referred to as the embodiment) will be described in detail with reference to the drawings.

[First Embodiment]

FIG. 1 shows the overall configuration of the image display device according to the first embodiment of the present invention.

The image display device of the present embodiment includes a display unit 1, a display signal generation unit 21, a display signal holding control unit 22, a display signal driver 23, a light emitting side scanner 24, a light receiving signal selection scanner 31, and receiving light. It includes a signal receiver 32, a light receiving signal holding unit 33, and a position detecting unit 34.

The display unit 1 is composed of, for example, an organic or inorganic EL (ElectroLuminescence) display or LCD (Liquid Crystal Display) in which a plurality of pixels 11 are arranged in a matrix over the entire surface, and operates in line sequence as described later. Display images such as predetermined figures and characters while doing. Further, each pixel 11 is composed of a light emitting / receiving cell CWR including one light emitting / receiving element, and each pixel has both a light emitting operation function and a light receiving operation function as described later.

The display signal generation unit 21 generates a display signal to be displayed for each screen (for each field display), for example, based on the supplied data generated by a CPU (Central Processing Unit) or the like (not shown). , It is output to the display signal holding control unit 22.

The display signal holding control unit 22 stores the display signal output from the display signal generation unit 21 for each screen (for each display of one field), for example, in a field memory composed of SRAM (Static Random Access Memory) or the like. A function to control the light emitting side scanner 24 and the display signal driver 23 that emit light and drive each light emitting and receiving cell CWR, and the light receiving signal selection scanner 31 that receives and drives each light emitting and receiving cell CWR to operate in conjunction with each other. Has. Specifically, the light emitting side scanner 24 has a light emitting timing control signal 41, the light receiving signal selection scanner 31 has a light receiving timing control signal 42, and the display signal driver 23 has a control signal and a display signal held in the field memory. Outputs the display signal for one horizontal line based on. The line sequential operation is performed by these control signals and display signals, as will be described later.

The light emitting side scanner 24 has a function of selecting a light emitting / receiving cell CWR to be light-emitting driven according to a light emitting timing control signal 41 output from the display signal holding control unit 22. Specifically, as will be described later, a selection signal is supplied via a light emitting gate line connected to each pixel 11 of the display unit 1 to control the first switch. That is, when a voltage for turning on the first switch of a certain pixel is applied by the selection signal, the pixel emits light with a brightness corresponding to the voltage supplied from the display driver 23. ..

The display signal driver 23 has a function of supplying display data to the light emitting / receiving cell CWR to be driven by light emission in response to the display signal for one horizontal line output from the display signal holding control unit 22. Specifically, as will be described later, a voltage corresponding to the display data is supplied to the pixel 11 selected by the light emitting side scanner 24 via the data supply line connected to each pixel 11 of the display unit 1. By interlocking the light emitting side scanner 24 and the display signal driver 23 to operate in line sequence, an image corresponding to arbitrary display data is displayed on the display unit 1.

The light-receiving signal selection scanner 31 switches between light-emitting drive and light-receiving drive of the light-emitting light-receiving element CWR according to the light-receiving timing control signal 42 output from the display signal holding control unit 22, thereby switching the light-receiving cell CWR to be light-receiving. Has a function to select. Specifically, as will be described later, a switching signal is supplied via a switching line connected to each pixel 11 of the display unit 1 to control the second switch and the third switch. That is, a voltage for turning off the second switch selected when the light emission is driven is applied to a certain pixel by the switching signal, and a voltage for turning on the third switch selected when the light receiving drive is driven is applied, and the voltage is applied from the pixel. The detected light receiving signal is output to the light receiving signal receiver 32. This makes it possible for another light emitting / receiving cell CWR to receive and detect the light reflected by an object that is in contact with or is close to the object based on the light emitted from a certain light emitting / receiving cell CWR, for example. Further, the light-receiving signal selection scanner 31 outputs a light-receiving block control signal 43 to the light-receiving signal receiver 32 and the light-receiving signal holding unit 33, and also has a function of controlling blocks that contribute to the light-receiving operation.

The light-receiving signal receiver 32 has a function of acquiring one horizontal line of light-receiving signals output from each light-emitting light-receiving cell CWR in response to the light-receiving block control signal 43 output from the light-receiving signal selection scanner 31. The light-receiving signal for one horizontal line acquired by the light-receiving signal receiver 32 is output to the light-receiving signal holding unit 33.

The light receiving signal holding unit 33 converts the light receiving signal output from the light receiving signal receiver 32 into a light receiving signal for each screen (for each field display) in response to the light receiving block control signal 43 output from the light receiving signal selection scanner 31. It has a function of reconfiguring and storing and holding it in a field memory composed of, for example, SRAM. The received light signal data stored in the light receiving signal holding unit 33 is output to the position detecting unit 34. The light receiving signal holding unit 33 may be composed of a storage element other than the memory, and for example, the light receiving signal data can be held as analog data. Hereinafter, in the present embodiment, unless otherwise specified, the received signal is held as analog data.

The position detection unit 34 has a function of performing signal processing based on the data of the light receiving signal output from the light receiving signal holding unit 33 and identifying the position where the object detected in the light emitting and receiving cell CWR exists. This makes it possible to identify the position of an object that is in contact with or in close proximity to it. When the light receiving signal holding unit 33 stores the light receiving signal data as analog data as described above, the position detecting unit 34 performs analog / digital conversion (hereinafter referred to as A / D conversion). Signal processing is performed.

FIG. 2 shows an example of the configuration of the display unit 1 in FIG. It is assumed that the display unit 1 has a configuration in which pixels 11 consisting of m pixels in the horizontal line direction and n pixels in the vertical line direction, for a total of (m × n), are arranged in a matrix. Here, for example, in the case of the display unit of the XGA (eXtended Graphics Array) standard, which is a general display standard in a PC (Personal Computer), m = 1024 × 3 (RGB), n = 768, a total of 2359296 pixels. Are arranged in a matrix.

As shown in FIG. 2, the display unit 1 corresponds to the pixels 11 composed of (m × n) in total, the above-mentioned light emitting and receiving cells CWR11 to CWRmn included in each pixel, and the number of the pixels 11. Connected m data supply lines DW (DW1 to DWm) and data read lines DR (DR1 to DRm), and n light emitting gate lines G (G1 to Gn) and switching lines S (S1 to Sn). And.

The data supply line DW, data read line DR, light emitting gate line G, and switching line S are connected to the above-mentioned display signal driver 23, light receiving signal receiver 32, light emitting side scanner 24, and light receiving signal selection scanner 31, respectively, and display signals. , The selection signal and the switching signal are supplied to each light emitting / receiving cell CWR, and the light receiving signal is output from each light emitting / receiving cell CWR. Further, as shown in FIG. 2, one data supply line DW, one data read line DR, a light emitting gate line G, and a switching line S are connected to each light emitting / receiving cell CWR. Further, for example, one data supply line DW1 and one data read line DR1 are commonly connected to one vertical line light emitting / receiving cell CWR11, CWR12, ..., CWR1n, for example, one horizontal line light emitting / receiving cell. One light emitting gate line G and one switching line S are commonly connected to CWR11, CWR21, ..., CWRm1. The arrow X in FIG. 2 indicates the scanning direction of the light emitting gate line G and the switching line S as described later.

FIG. 3 schematically shows an example of the arrangement configuration of the light emitting / receiving cell CWR in the display unit 1 of FIG. 1 in a cross-sectional view. In the example of FIG. 3, the light emitting / receiving element included in the light emitting / receiving cell CWR is an organic EL element, and an organic EL layer is provided between a pair of transparent substrates. In this figure, i, which is a code representing a position, represents a natural number, and as described above, for example, in the case of an XGA standard display unit (m = 1024 × 3 (RGB), n = 768), for example, the center of the display unit. If it is a vertical line of, i = 1536.

Further, the cross-sectional view shown in FIG. 3 corresponds to the vertical AA arrow-viewing cross section in the display unit 1 shown in FIG. The display unit 1 is arranged between a pair of transparent substrates 12A and 12B and these transparent substrates 12A and 12B, and a plurality of light emitting and receiving cells CWR (CW21) having a structure separated from each other by a partition wall 13 as described above. , CW22, CW23, CW24, CW25, ...). Further, as described above, the light emitting / receiving cell CWR includes an organic EL element as a light emitting / receiving element. In addition, this figure also shows the emitted light LW by the light emitting / receiving element included in each light emitting / receiving cell CWR. The other layers in the general organic EL display unit are not shown and are omitted. Hereinafter, the same applies to FIG.

The cross-sectional view of the arrangement configuration example of the light emitting / receiving cell CWR in the display unit 1 according to the present embodiment is not limited to these, and other arrangement configurations may be used. Further, in the example of the cross-sectional view shown in FIG. 3, the example in which the light emitting / receiving element EL is composed of an organic EL element has been described, but this light emitting / receiving element is another element as long as it has a light emitting function and a light receiving function. It may be made of, for example, an LED element or the like.

FIG. 4 shows the circuit configuration of the light emitting / receiving cell CWR in FIG.

This light emitting / receiving cell CWR includes one light emitting / receiving cell CWR, and has a configuration in which a light emitting gate line G, a data supply line DW, a switching line S, and a data reading line DR are connected to this light emitting / receiving cell CWR. .. That is, the gate line and the data line are increased by one by the amount for receiving light, as compared with the cell for one pixel provided with a normal light emitting element. Further, the light emitting / receiving cell CWR includes one light emitting / receiving element EL, a capacitor C, a resistor R, and a data supply line DW and one end of the capacitor C according to a selection signal supplied from the light emitting gate line G. The first switch SW1 that selectively conducts between them, and the second switch that selectively conducts between the other end of this capacitor and one end of the light emitting / receiving element EL according to the switching signal supplied from the switching line S. It also has a switch SW2 and a third switch SW3 that selectively conducts between one end of the light emitting / receiving element EL and the data reading line DR according to the switching signal supplied from the switching line S. The other end of the element EL is grounded. One end of the resistor R is connected to the data read line DR, and the other end of the resistor R is connected to ground or a negative bias point (not shown).

Here, the operation of each component during the light emitting operation and the light receiving operation will be specifically described. First, the light emitting operation and the light receiving operation are performed by utilizing the following properties of the light emitting and receiving element EL. That is, in the present embodiment, for example, an organic EL element or an LED element configured as a light emitting / receiving element performs a light emitting operation when a forward bias voltage is applied, but when a reverse bias voltage is applied, it receives a light and receives a current. It has the property of generating. Therefore, as will be described later, the light emitting / receiving element EL cannot perform the light emitting operation and the light receiving operation at the same time, and must be operated in a time division manner in order to perform both operations.

Therefore, first, during the light emitting operation, the first switch SW1 and the second switch SW2 are in the ON state according to the selection signal supplied from the light emitting gate line G and the switching signal supplied from the switching line S as described above. When the third switch SW3 is turned off, a forward bias voltage is applied to the light emitting / receiving element EL. Here, the capacitor C is charged along the path from the data supply line DW to I1 so that the light emission has a brightness corresponding to the display signal, and based on this, a current flows through the light emitting and receiving element EL along the path of I2, and the light emitting operation is performed. Is supposed to do.

On the other hand, during the light receiving operation, the second switch is turned off and the third switch SW2 is turned on according to the switching signal supplied from the switching line S as described above, and the light emitting and receiving element EL is biased in the reverse direction. A voltage is applied, and a current corresponding to the amount of light received by the light emitting / receiving element EL is supplied to the data read line DR through the path of I3 to perform the light receiving operation. When neither the light emitting operation nor the light receiving operation is performed, all the switches of the first switch SW1, the second switch SW2, and the third switch SW3 are in the off state, and the data supply line DW And the data read line DR are disconnected from the light emitting / receiving element EL, respectively. The resistor R connected to the data read line creates a potential difference at both ends of the resistor R based on the current supplied to the data read line DR in the path of I3 as described above, and outputs this as a light receiving signal. Has the function of

Next, an operation of detecting an object in contact with or in close proximity to the image display device having the above configuration will be described.

First, with reference to FIG. 5, the operation of detecting an object in contact with or in close proximity to the image display device having the above configuration will be described. FIG. 5 shows an example of processing for detecting an object to be detected in the image display device of FIG. This corresponds to the example of the structure in which the light emitting / receiving cell CWR including the organic EL element which is the light emitting / receiving element shown in FIG. 4 is separated by the partition wall 13, and has the same constituent elements as those shown in FIG. Have the same reference numerals, and description thereof will be omitted as appropriate.

As shown in FIG. 5, when a detection target object 15 such as a finger is brought into contact with or close to the display unit 1, for example, the emitted light LW1 emitted from the light emitting / receiving cell CWR23 is reflected by the detection target object 15. Here, since the light emitting / receiving element EL needs to perform the light emitting operation and the light receiving operation in a time-division manner as described above, it is not possible to receive the reflected light by the light emitting / receiving element while causing the light emitting / receiving element to emit light. Therefore, the light emitted from the light emitting / receiving element of a certain horizontal line can be detected by applying a reverse bias voltage to the light emitting / receiving element of another horizontal line to perform a light receiving operation. For example, the reflected light LR1 is incident on the light emitting / receiving cell on the horizontal line close to the light emitting / receiving cell CWR23, for example, CWR24 or CWR25, but the reflected light is reflected on the light emitting / receiving cell on the horizontal line far from the light emitting / receiving cell CWR23. Does not enter. Therefore, the light-receiving signal can be obtained only from the light-emitting light-receiving cell CWR, which is close to the detection target object 15. For example, the timing is such that the light emitted from the light emitting / receiving cell CWR of the horizontal line that is driven to emit light and reflected by the object to be detected 15 is detected by the light emitting / receiving element of the horizontal line adjacent to the horizontal line during light emission. It shall be driven. Since the light receiving signal is detected from the light emitting and receiving element of the horizontal line near the detection target object 15, the light receiving signal is not detected from the other regions, so that the detection target object 15 exists at any position on the display unit 1. It becomes possible to detect whether or not. By sequentially performing such light emission drive and light reception drive for each horizontal line (hereinafter referred to as line sequential drive), it is possible to detect the object to be detected 15 while displaying an image over the entire display unit 1. ..

FIG. 6 shows an example of the line sequential light emitting operation and the line sequential light receiving operation in the image display device of FIG. Here, one cell shown in FIG. 6 represents the pixel 11 in the display unit 1.

In the example of the line sequential light emission operation shown in FIG. 6 (A), for example, one horizontal line at the position indicated by the arrow P2 represents a situation in which the line sequential light emission operation is sequentially performed in the direction indicated by the scan direction X. Further, in this example, one horizontal line at the position indicated by the arrow P2 is for a certain period of time until a certain time elapses on the screen for drawing by the display data, that is, before the next image data is supplied by the display driver 23. Only the light emitting state is maintained, and the entire display unit 1 is divided into light emitting areas 51A and 51B and non-light emitting areas 52. In this case, since one horizontal line at the position indicated by the arrow P2 sequentially emits light, the entire or most of the display unit 1 becomes a light emitting region within a certain period of time when the light emitting state is maintained, and certain image data. Can be displayed over the entire display unit 1. The period during which the light emitting state is maintained is determined by, for example, the capacitance value of the capacitor C in the circuit configuration of the light emitting / receiving cell CWR shown in FIG. 4, and can be arbitrarily set. In the example shown in FIG. 6A, the non-emission region 52 exists in the display unit 1, but since the non-emission region 52 also moves in line sequence, it can be visually recognized by the human eye due to the afterimage phenomenon effect. It doesn't matter because it isn't done.

Next, in the example of the line sequential light emission operation and the line sequential light reception operation shown in FIGS. 6 (B) and 6 (C), for example, one horizontal line at the position indicated by arrows P2 and P5 is sequentially in the direction indicated by the scan direction X. Along with the light emission operation, the 1 horizontal line at the position indicated by arrows P3 and P6 sequentially receives the light reflected by the light emitted from the light emission region 51A at the detection target object 15 in the direction indicated by the scan direction X. It represents the situation to be done. In this way, one horizontal line sequentially emits light in a line, and one horizontal line next to it always receives the reflected light from the emitted light in a sequential line manner, so that the entire display unit 1 becomes a light emitting region. In addition to displaying a certain image data over the entire display unit 1, whether or not a certain detection target object 15 exists in the vicinity of the display unit 1 by the light receiving signal detected from the light receiving element. If so, the position can be detected. Even in this case, the light emitting operation is maintained for a certain period of time until a certain time elapses on the screen, that is, before the next light receiving operation, and the entire display unit 1 does not emit light with the light emitting areas 51A and 51B. It shows the situation where it is separated from the area 52.

Next, the details of the process of detecting the object to be detected 15 in the image display device of FIG. 1 will be described with reference to FIGS. 2, 4, 5, and 7. FIG. 7 shows the process of detecting the object to be detected 15 in the image display device of FIG. 1. (D) Light emitting / receiving cells CWRi (CWRi1 to CWRin) for one vertical line, and each of these light emitting / receiving cells. Each of (A) data supply line DWi, (B) light emitting gate line G (G1 to Gn), (C) switching line S (S1 to Sn), and (E) data read line DRi connected to cell CWRi. Shows a signal. Further, in FIG. 7, the symbols i and j representing the positions represent a certain natural number, and as described above, for example, in the case of the display unit of the XGA standard (m = 1024 × 3 (RGB), n = 768), for example, the display unit. If it is the center of, i = 1536, j = 384. The same applies to the subsequent timing diagrams.

In FIG. 7, the horizontal axis represents time, and the vertical periods TH1 and TH2 are the time required to scan the entire screen of the display unit 1, that is, in this case, the light emitting side scanner 24 and the light receiving signal selection scanner 31 are G1 to G1 respectively. It represents the time to scan up to Gn and from S1 to Sn. Here, assuming that the object to be detected 15 is near the light emitting and receiving cells CWRij, CWRi (j + 1), and CWRi (j + 2) on the display unit 1, the timing is set in the corresponding period, that is, the vertical period TH1. The light receiving signal is detected in the period from t3 to t6 (light receiving signal detection period TF1), and in the vertical period TH2, the light receiving signal is detected in the light receiving signal detection period TF2. The vertical axis represents the voltage at each timing of each signal shown in (A) to (C) and (E) above. Here, it is assumed that the signal of the data supply line DWi shown in (A) is display data corresponding to an arbitrary brightness in each pixel 11, and an arbitrary image is displayed on the display unit 1. It also represents the light emission period TW and the light reception period TR in each light emission / reception cell CWRi shown in (D). The period other than the light emitting period TW and the light receiving period TR is a non-operating period. The first section (thick frame part) of the light emission period TW is the period during which the light emission drive based on the image data is performed (the period during which the first switch SW1 in FIG. 4 is on). The period other than the period is the period in which the light emitting state is held by the capacitor C in FIG.

The signal of the data read line DRi shown in (E) is an example of being stored in the light receiving signal holding unit 33 as analog data, but as described above, it is stored in the light receiving signal holding unit 33 as digital data. It is also possible to configure.

First, no selection signal is output on all the light emitting gate lines G and the switching line S, and any of the first switch SW1, the second switch SW2, and the third switch SW3 in each light emitting and receiving cell CWR. Is also off, and the data supply line DW and the data read line DR are disconnected from the light emitting / receiving element EL, respectively. Therefore, during this period, each light emitting / receiving cell CWR is in a non-operating state.

At timing t0, (C) a switching signal is output on the switching line S1, and the third switch SW3 on the light emitting and receiving cells CWR11, CWR21, ..., CWRm1 to which this switching line is connected is turned on all at once. The light receiving operation is performed in the light emitting and receiving cell of. The first switch SW1 and the second switch SW2 in these light emitting and receiving cells remain in the off state. At this time, as shown by the light receiving period TR in FIG. 7, (D) the current corresponding to the amount of light received by the light emitting and receiving element EL shown in FIG. 4 in the light emitting and receiving cell CWRi is (E) in the path of I3. It is supplied to the data read line DRi and performs a light receiving operation. Since the light receiving signal by the detection target object 15 is not detected during this period (timing t0 to t1), the output signal is not output from the (E) data read line DRi.

Next, at the timing t1, the selection signal and the switching signal are output at (B) the light emitting gate line G1 and (C) the switching line S2, respectively. Therefore, in (B) the light emitting and receiving cells CWR11, CWR21, ..., CWRm1 to which the light emitting gate wire G1 is connected, the first switch SW1 and the second switch SW2 are turned on all at once and the timing t0. The third switches, which were on in ~ t1, are turned off all at once, and the light emitting and receiving cells perform light emitting operation. However, since the light receiving signal by the object to be detected 15 is not detected, (E) data read line. No output signal is output from DRi.

In the same manner after timing t2, (B) light emitting gate line G2 and (C) switching line S3, (B) light emitting gate line G3 and (C) switching line S4, ... And the light receiving operation is performed, but since the light receiving signal by the detection target object 15 is not detected, the output signal is not output from the (E) data read line DRi. As described above, each light emitting / receiving cell CWRi retains the light emitting operation period TW for a certain period of time.

Then, at timings t3 to t6, (D) the light emitting and receiving cells CWRij, CWRi (j + 1), and CWRi (j + 2) receive the reflected light from the detection target object 15, and receive the light as shown in FIG. The current corresponding to the amount of light is converted into a voltage and output to (E) the data read line DRi (light receiving signal detection period TF1). In this case, mainly (D) each light emitting / receiving cell CWRij, CWRi (j + 1), CWRi (j + 2) is arranged on the adjacent horizontal line CWRi (j-1), CWRij, CWRi. Since the reflected light from the emitted light due to the light emission operation of (j + 1) is received, the signal output to (E) the data read line DRi is a value corresponding to (A) the signal on the data supply line DWi. It has become.

After timing t6, as with timings t1 to t3, (B) light emitting gate line Gj + 2 and (C) switching line Sj + 3, (B) light emitting gate line Gj + 3 and (C) switching line Sj + 4, ..., (B) Gate line Gn-1 for light emission and (C) Switching line Sn, light emission operation and light reception operation are performed in sequence, but the light reception signal by the detection target object 15 is not detected. (E) No output signal is output from the data read line DRi.

In this way, it can be detected that the detection target object 15 exists at a position near the light emitting / receiving cells CWRij, CWRi (j + 1), and CWRi (j + 2) in the vertical period TH1. The same operation is performed after the vertical period TH2. For example, in the vertical period TH2, the output signal is output from the (E) data read line DRi in the received signal detection period TF2, and the light emitting and receiving cells CWRij, CWRi (j + 1), CWRi also operate. Detects that the object to be detected 15 exists at a position near (j + 2).

As described above, according to the image display device and the driving method of the image display device of the present embodiment, a plurality of light emitting / receiving cell CWRs having a light emitting / receiving cell CWR including one light emitting / receiving element EL are arranged. The light emitting side scanner 24 and the display signal driver 23 drive these light emitting and receiving element ELs based on the image data generated by the display signal generating unit 21, and emit out from the light emitting and receiving elements. The light-receiving signal selection scanner 31 drives another light-emitting light-receiving element EL so as to receive the light reflected by the object 15 to be detected, and the position detection unit is based on the light-receiving signal obtained by the light-receiving signal receiver 32 from the other light-receiving element. Since the object 15 to be detected is detected in 34, it is not necessary to add a separate component such as a touch panel or an input device to secure a simple structure, and the light emitted from the display unit 1 is a touch panel or the like. Since it is not necessary to pass through separate parts, it is possible to detect the position of an object without causing deterioration in image quality.

Further, according to the image display device and the driving method of the image display device of the present embodiment, each light emitting / receiving cell CWR performs a line sequential light emitting operation and a line sequential light receiving operation. It is possible to display image data and detect the position of an object.

Further, according to the image display device and the driving method of the image display device of the present embodiment, the position or the like is detected by touching or bringing the detection target object such as a finger on or close to the display unit 1. The user can conveniently operate the same operation as the touch panel.

Further, according to the image display device and the driving method of the image display device of the present embodiment, both the light emitting operation and the light receiving operation are performed in a time-divided manner in the light emitting / receiving cell CWR including one light emitting / receiving element EL. Therefore, it is not necessary to separately install the light emitting element and the light receiving element, and the light emitting operation and the light receiving operation can be performed with a simple element structure, and the manufacturing process can be simplified.

[Second Embodiment]

Next, a second embodiment of the present invention will be described.

In the first embodiment described above, an image display device having a configuration in which the light emitting operation is maintained for a certain period of time before the next light receiving operation has been described, but in the present embodiment, immediately before the next light receiving operation is performed. An image display device configured to emit light until a period of time will be described.

FIG. 8 shows the overall configuration of the image display device according to the second embodiment of the present invention. In this figure, the same components as those shown in FIG. 1 are designated by the same reference numerals, and the description thereof will be omitted as appropriate. This image display device includes a display unit 101, a display signal generation unit 21, a display signal holding control unit 22, a display signal driver 23, a light emitting side scanner 24, a light receiving signal selection scanner 31, and a light receiving signal receiver 32. , A light receiving signal holding unit 33 and a position detecting unit 34 are provided. That is, the display unit 101 is provided in place of the display unit 1 in the first embodiment shown in FIG.

Similar to the display unit 1, the display unit 101 has a plurality of pixels 11 arranged in a matrix over the entire surface, and displays an image such as a predetermined figure or character while performing line sequential operation. The difference from the display unit 1 is that the light emitting operation is performed until the period immediately before the next light receiving operation as described above. That is, as described above, the capacitance value of the capacitor C in the circuit configuration of the light emitting / receiving cell CWR is changed to extend the light emitting period.

Next, an operation of detecting an object in contact with or in close proximity to the image display device having the above configuration will be described.

FIG. 9 shows an example of the line sequential light emitting operation and the line sequential light receiving operation in the image display device of FIG. 8, and corresponds to FIG. 6 in the first embodiment. In this figure, the same components as those shown in FIG. 6 are designated by the same reference numerals, and the description thereof will be omitted as appropriate.

In the example of the line sequential emission operation shown in FIG. 9 (A), for example, one horizontal line at the position indicated by the arrow P2 sequentially emits light in the direction indicated by the scan direction X, as in the example of FIG. 6 (A). It represents the situation to be done. Also, in this example, unlike the example of FIG. 6 (A), one horizontal line at the position indicated by the arrow P2 is displayed until the drawing by the display data makes a round on the screen, that is, the next image data is displayed by the display driver 23. It represents a situation in which the light emitting operation is maintained until the data is supplied, and the entire display unit 1 is in the light emitting region 51. In this way, the 1 horizontal line at the position indicated by the arrow P2 emits light in a line-sequential manner, so that the entire display unit 1 becomes a light emitting region except for the light receiving line, and a certain image data is displayed over the entire display unit 1. It becomes possible.

Next, in the example of the line sequential light emitting operation and the line sequential light receiving operation shown in FIGS. 9 (B) and 9 (C), the positions indicated by arrows P2 and P5, for example, are the same as in the examples of FIGS. 9 (B) and 9 (C). The 1 horizontal line of No. 1 emits light in the direction indicated by the scanning direction X, and the 1 horizontal line at the positions indicated by arrows P3 and P6 emits the reflected light of the object 15 to be detected by the light emitted from the light emitting region. , Indicates a situation in which line-sequential light receiving operation is performed in the direction indicated by the scanning direction X. However, the difference from the examples in FIGS. 9 (B) and 9 (C) is that the 1 horizontal line at the position indicated by arrows P3 and P6 is not only the light emitting area 51A at the upper position but also the light emitting area at the lower position. The point is that the reflected light from the light emitted from 51B is also received. In this way, by changing the capacitance value of the capacitor C in the circuit configuration of the light emitting / receiving cell CWR and extending the light emitting period, one horizontal line always detects the position of the object by the line sequential light receiving operation. It is possible to use the light emitted from one horizontal line at the upper and lower positions as a light source.

FIG. 10 shows a process of detecting the object to be detected 15 in the image display device of FIG. Since the basic operation of the driving method of the image display device in the present embodiment is the same as the basic operation of the driving method of the image display device in the first embodiment, the description thereof is omitted and the light emitting period TW Only the operation related to the extension will be described.

First, in the vertical period TH1, the operation is the same as in the case of the first embodiment shown in FIG. Then, in the vertical period TH2, as described above, in each light emitting / receiving cell CWR, the light emitting period TW is set until immediately before the light receiving period TR. Specifically, for example, the light emitting / receiving cell CWRi1 had a non-operating period at timings t7 to t8 in the case of the first embodiment (FIG. 7), but in the present embodiment, at timings t7 to t8. Also has a light emission period of TW. As a result, the light emission period TW is from timing t1 to t8 (that is, until immediately before the light receiving period TR). For example, in the case of the light emitting / receiving cell CWRij, at the timings t11 to t12, both the light emitting / receiving cells CWRi (j-1) and CWRi (j + 1) in the upper and lower horizontal lines have the light emitting period TW. That is, it is possible to use the light emitted from the light emitting / receiving elements of the two horizontal lines above and below the light emitting / receiving cell that is being driven to receive light as a light source. In other words, the state of one light emitting / receiving element repeatedly transitions in the order of "light emission"-&gt; "light reception"-&gt; "light emission"-&gt; "light reception" without interposing a light-off period, but is a horizontal line driven by light reception. The light emitted from the light emitting and receiving elements of the upper and lower horizontal lines sandwiching the horizontal line and reflected by the detection target object 15 is incident on the light emitting and receiving element. Since the total amount of emitted light used as a light source increases, as shown in FIG. 10 (E), the signal amount of the received signal on the data read line DRi increases as compared with the first embodiment (FIG. 7). , The light receiving sensitivity is improved. In this case, if there is a difference in the display data (video data) between the fields, there may be a problem that the received signal does not correspond to the original display data, but data that is too different between the fields is not displayed. It is possible to avoid this problem by devising such a method. A normal video signal has such characteristics (there is almost no difference in video data between fields), for example, MPEG (Motion Picture Experts).

In this way, according to the image display device and the driving method of the image display device in this modification, the light emission operation is performed until the period immediately before the next light receiving operation, so that the emitted light used as the light source increases. In addition to the effect in the first embodiment, it is possible to increase the signal amount of the received signal to improve the S / N ratio and increase the detection sensitivity.

Hereinafter, the first and second embodiments will be described with some modifications. These modifications can be applied to any of the first and second embodiments, but in the following description, the procedure will proceed based on the first embodiment.

[Modification example 1]

First, a modification 1 common to the first and second embodiments will be described. In this modification, in the first embodiment, the light receiving drive is thinned out with respect to the light emitting drive.

FIG. 11 shows the overall configuration of the image display device according to the first modification, and corresponds to FIG. 1 in the first embodiment. In this figure, the same components as those shown in FIG. 1 are designated by the same reference numerals, and the description thereof will be omitted as appropriate. This image display device includes a display unit 1, a display signal generation unit 21, a display signal holding control unit 22, a display signal driver 23, a light emitting side scanner 24, a light receiving signal selection scanner 311 and a light receiving signal receiver 32. , A light receiving signal holding unit 33 and a position detecting unit 34 are provided. That is, the light receiving signal selection scanner 311 is provided in place of the light receiving signal selection scanner 31 according to the first embodiment shown in FIG.

Similar to the light-receiving signal selection scanner 31, the light-receiving signal selection scanner 311 switches between light-emitting drive and light-receiving drive of the light-emitting light-receiving element CWR according to the light-receiving timing control signal 42 output from the display signal holding control unit 22, thereby receiving light. It has a function to select the light emitting / receiving cell CWR to be driven. The difference from the light receiving signal selection scanner 31 is that the light receiving side scanner 311 is thinned out and driven with respect to the light emitting side scanner 24 as described above. Specifically, as will be described later, the light emitting side scanner 24 scans the light emitting gate line G as G1, G2, G3, ..., Gn as in the first embodiment, whereas the light receiving side scanner 24 scans the light emitting gate line G as G1, G2, G3, ..., Gn. The signal selection scanner 311 scans the switching lines S as S2, S4, S6, ..., Sn every other line, and the remaining switching lines S1, S3, S5, ..., Sn-1 scan. It is designed not to be done. As described above, the display unit 1 considers, for example, the case of the XGA standard (m = 1024 × 3 (RGB), n = 768), and n is an even number. Also, for convenience, j is assumed to be an odd number.

FIG. 12 represents a process of detecting the object to be detected 15 in the image display device of FIG. 11, and corresponds to FIG. 7 in the first embodiment. Since the basic operation of the driving method of the image display device in this modification is the same as the basic operation of the driving method of the image display device in the first embodiment, the description thereof is omitted and the light receiving signal selection scanner 311 Only the operation related to is explained.

As described above, (B) the light emitting gate line G outputs selection signals such as G1, G2, G3, ..., Gn as in the first embodiment, whereas (C) switching line. S outputs switching signals every other line such as S2, S4, ..., Sj-1, Sj + 1, ..., Sn, and the remaining switching lines S1, S3, Sj, .. No switching signal is output to ., Sn-1. Therefore, the output signal of the data read line DR is also thinned out corresponding to the switching line S, and the received signal is not detected during the period of timing t1 to t2, t3 to t4, t5 to t6, for example, timing t4 to t5. The received signal is detected during the period of the above, and the amount of data of the received signal can be reduced.

In this way, according to the image display device and the driving method of the image display device in the present modification, the light receiving signal selection scanner 31 is thinned out and driven with respect to the light emitting side scanner 24. In addition to the effect in the form, the amount of light-receiving signal data can be reduced, the circuits on the light-receiving side (light-receiving signal selection scanner 311, light-receiving signal receiver 32, light-receiving signal holding unit 33) can be simplified, and power consumption can be reduced. It will be possible. Therefore, it is particularly effective when it is desired to simplify the circuit configuration and reduce the power consumption rather than the accuracy of the detection position of the object in contact with or in the vicinity.

In this modification, the example of scanning only the even-numbered light-receiving gate wire has been described, but the configuration of this modification is not limited to this, and the circuit on the light-receiving side is simplified to reduce power consumption. Other configurations are possible as long as they can be converted. For example, conversely, only odd-numbered light-receiving gate lines may be scanned, or, for example, every two or three light-receiving gate lines may be scanned. As another method of performing "thinning out" as in this modification, a method of combining the output of pixels and reducing the number of light receiving signal scanners can be considered. For example, if the outputs of two vertical pixels are combined, the amount of signals that can be extracted is doubled and the light receiving sensitivity is improved.

[Modification 2]

Next, a modification 2 common to the first and second embodiments will be described. In this modification, the comparator 35 is arranged between the light receiving signal receiver 32 and the light receiving signal holding unit 33 in the first embodiment.

FIG. 13 shows the overall configuration of the image display device according to the second modification, and corresponds to FIG. 1 in the first embodiment. In this figure, the same components as those shown in FIG. 1 are designated by the same reference numerals, and the description thereof will be omitted as appropriate. This image display device includes a display unit 1, a display signal generation unit 21, a display signal holding control unit 22, a display signal driver 23, a light emitting side scanner 24, a light receiving signal selection scanner 31, and a light receiving signal receiver 32. , The scanner 35, the received signal holding unit 33, and the position detecting unit 34 are provided.

The comparator 35 has a function of comparing the light receiving signal output from the light receiving signal receiver 32 with the threshold voltage signal Vt, which is a predetermined voltage output from the display signal holding control unit 22, and performing A / D conversion. Have. Specifically, as will be described later, the received signal is converted into digital data, for example, 1 when the received signal is higher than the threshold voltage signal Vt, 0 when the received signal is lower than the threshold voltage signal Vt, and so on. .. Further, the data converted into this digital data (comparator output signal Vc) is output to the light receiving signal holding unit 33.

FIG. 14 represents a process of detecting the object to be detected 15 in the image display device of FIG. 13, and corresponds to FIG. 7 in the first embodiment. Further, in this figure, (D) one vertical line of light emitting / receiving cells CWRi (CWRi1 to CWRin), and (A) data supply lines DWi, (B) connected to each of these light emitting / receiving cells CWRi. Light emitting gate lines G (G1 to Gn) and (C) switching lines S (S1 to Sn), (E) data read line DRi, (F) threshold voltage signal Vt, (G) comparator output signal Vci Shows a signal.

The basic operation of the driving method of the image display device in this modification is the same as the basic operation of the driving method of the image display device in the first embodiment, and the difference is that the light receiving signal receiver 32 and the light receiving light are received as described above. By arranging the comparator 35 between the signal holding unit 33 and the signal holding unit 33, the comparator output voltage Vc, that is, the input signal to the received signal holding unit 33 is digital data. Therefore, if the signal amount of (E) data read line DRi is larger than the predetermined (F) threshold voltage signal Vt, (G) comparator output signal Vci becomes 1, and conversely, (E) data read line DRi. If the signal amount is smaller than the predetermined (F) threshold voltage signal Vt, the (G) comparator output signal Vci is 0. In this way, as in the case of the first embodiment shown in FIG. 7, when the light receiving signal is obtained during the light receiving element detection periods TF1 and TF2, the light emitting and receiving cells CWRij, CWRi (j + 1), CWRi ( It can be detected that the object to be detected 15 exists at a position near j + 2).

In this way, according to the image display device and the driving method of the image display device in the present modification, the comparator 35 is arranged between the light receiving signal receiver 32 and the light receiving signal holding unit 33, so that the light receiving signal is held. Since the data handled by the unit 33 and the position detection unit 34 are digital data, in addition to the effects in the first embodiment, the processing load is suppressed in these blocks to simplify the circuit configuration and reduce the power consumption. It becomes possible.

FIG. 15 shows another overall configuration example of the image display device according to the second modification. In this example, the shift register 36 is further arranged between the light receiving signal receiver 32 and the comparator 35 in the modified example 2 shown in FIG. In this figure, the same components as those shown in FIG. 13 are designated by the same reference numerals, and the description thereof will be omitted as appropriate. This image display device includes a display unit 1, a display signal generation unit 21, a display signal holding control unit 22, a display signal driver 23, a light emitting side scanner 24, a light receiving signal selection scanner 31, and a light receiving signal receiver 32. , A shift register 36, a scanner 351 and a light receiving signal holding unit 33, and a position detecting unit 34 are provided.

The shift register 36 sequentially selects the light-receiving signal output from the light-receiving signal receiver 32 with the shift register according to the light-receiving block control signal 43 output from the light-receiving signal selection scanner 31, and performs parallel / serial conversion to perform a comparator. It has a function to output to 351. Specifically, by outputting the received signal, which is parallel data for m outputs, to the comparator 351 as serial data for one output, the number of comparators is reduced from m to one as compared with the configuration shown in FIG. It becomes possible to do.

The comparator 351 has a predetermined voltage output from the display signal holding control unit 22 for the received signal output from the shift register 36 and which has undergone parallel / serial conversion as described above, similarly to the comparator 35. It has a function to perform A / D conversion in comparison with the value voltage signal Vt. Further, the data converted into this digital data (comparator output signal Vc) is output to the light receiving signal holding unit 33.

In this way, according to the image display device and the driving method of the image display device in FIG. 15, the shift register 36 is further arranged between the light receiving signal receiver 32 and the comparator 351 in the modification 2 shown in FIG. Therefore, in addition to the effect of Modification 2, the number of comparators can be reduced, the processing load can be reduced in these blocks, and the circuit configuration can be simplified and the power consumption can be reduced. Become.

Here, the effect when this threshold value is changed will be described.

FIG. 16 shows an example of the distribution of the signal amount of the received light signal, and shows each light emitting and receiving cell (CWR (i-4) (j-5) to CWR (i + 4) centered on the light emitting and receiving cell CWRij. ) (J + 5)) is shown.

In this example, the light receiving signal 61 in the light emitting and receiving cell CWRij has a light receiving signal level of 9, and the light emitting and receiving cells CWRi (j-1), CWR (i + 1) j, CWRi (j + 1), CWR (i-1). Each light receiving signal 62A to 62D in j has a light receiving signal level of 5, and the light emitting and receiving cells CWR (i + 1) (j-1), CWR (i + 1) (j + 1), CWR (i-1) (j). The light receiving signals 63A to 63D in each of the light receiving signals 63A to 63D in +1) and CWR (i-1) (j-1) have a light receiving signal level of 3, and the light emitting and receiving cells CWR (i + 2) j, CWRi (j + 2), CWR (i). -2) The received signal level of each received signal 64A to 62C in j and the received signal in CWRi (j-2) (not shown) is 1, and the received signal level increases as the position moves away from the light emitting and receiving cell CWRij. The distribution is such that As described above, the position detection unit 34 and the comparators 35 and 351 detect the position of an object in contact or proximity by comparing the signal amount of each of these received light signals with a certain threshold voltage Vt. be able to.

FIG. 17 shows a case where the threshold value is changed in the distribution of the signal amount of the received signal of FIG. 36 (A), (B), and (C) show the case where the threshold voltage Vt is set to the received signal level 2, the received signal level 4, and the received signal level 6 in FIG. 35, respectively. The regions indicated by the light-receiving signal detection regions 65 to 67 are regions in which the signal amount of the light-receiving signal in the light-emitting light-receiving cell CWR at that position is larger than the threshold voltage Vt, and an object is detected at that position. Indicates that it was done.

In this way, as the received signal level of the threshold voltage is increased in the order of (A) (B) (C), the area of the region where the object is detected is centered on the position of the light emitting and receiving cell CWRij. You can see that it is getting smaller. Therefore, for example, the user can detect the properties of an object (size, surface condition (reflectance, color, roughness, etc.)), the purpose of detection (position detection, size detection, color detection, etc.), and detection. By arbitrarily changing the threshold voltage Vt depending on the accuracy or the like, more accurate and convenient position detection becomes possible.

[Modification 3]

Next, a modification 3 common to the first and second embodiments will be described. The amount of reflected light when an object is in contact with or in close proximity is large when the amount of light emitted from the light emitting / receiving cell CWR is high, and is small when the amount of light emitted from the light emitting / receiving cell CWR is low. Therefore, the signal amount of the light receiving signal detected by the other light emitting / receiving cell also differs depending on the amount of light emitted by a certain light emitting / receiving cell CWR. Therefore, in this modification, in the first embodiment, the shift register 36 and the comparator 351 are arranged between the light receiving signal receiver 32 and the light receiving signal holding unit 33, and the display signal output from the display signal control unit 22 is further arranged. The threshold voltage generation unit 37 that generates the threshold voltage Vt in the comparator 351 is arranged based on 45. That is, the image display device shown in FIG. 15 has a configuration in which a threshold voltage generation unit 37 that generates a threshold voltage Vt is added.

FIG. 18 shows the overall configuration of the image display device according to the third modification, and corresponds to FIG. 1 in the first embodiment. In this figure, the same components as those shown in FIGS. 1 and 15 are designated by the same reference numerals, and the description thereof will be omitted as appropriate. This image display device includes a display unit 1, a display signal generation unit 21, a display signal holding control unit 22, a display signal driver 23, a light emitting side scanner 24, a light receiving signal selection scanner 31, and a light receiving signal receiver 32. , A shift register 36, a scanner 351 and a threshold voltage generation unit 37, a light receiving signal holding unit 33, and a position detecting unit 34 are provided.

The threshold voltage generation unit 37 has a function of generating a threshold voltage Vt in the comparator 351 based on the display signal 45 in each pixel 11 output from the display signal control unit 22 and outputting it to the comparator 351. Therefore, in the comparator 351, the threshold voltage Vt corresponding to the emitted light of the light emitting / receiving cell CWR in each pixel 11 can be set for each pixel.

FIG. 19 represents a process of detecting the object to be detected 15 in the image display device of FIG. 18, and corresponds to FIG. 7 in the first embodiment and FIG. 14 in the second modification. Further, in this figure, as in FIG. 14, (D) the light emitting / receiving cells CWRi (CWRi1 to CWRin) for one vertical line, and (A) the data supply line DWi connected to each of these light emitting / receiving cells CWRi. , (B) Light emitting gate line G (G1 ~ Gn) and (C) Switching line S (S1 ~ Sn), (E) Data read line DRi, (F) Threshold voltage signal Vt, (G) Comparator output Signals Each signal of Vci is shown. Since the basic operation of the driving method of the image display device in this modification is the same as the operation shown in FIG. 14, the description thereof is omitted, and only the operation related to the threshold voltage generator 37 and the comparator 351 is described. To do.

The basic operation of the driving method of the image display device in this modification is the same as the basic operation of the driving method of the modification 2 shown in FIG. 14, and the difference is that the display signal control unit 22 outputs the difference as described above. The point is that the threshold voltage Vt in the comparator 351 is generated based on the display signal 45 in each pixel 11. Therefore, in the case of the modification 2 shown in FIG. 14, the threshold voltage Vt was a constant value, whereas in this modification, the threshold voltage signal Vt corresponds to (A) the data supply line DWi. It is a variable value. Of course, also in this case, if the signal amount of the (E) data read line DRi is larger than the predetermined (F) threshold voltage signal Vt, the (G) comparator output signal Vci becomes 1, and conversely, (E) data read. If the signal amount of the line DRi is smaller than the predetermined (F) threshold voltage signal Vt, the (G) comparator output signal Vci becomes 0. In this way, as in the case of the first embodiment shown in FIG. 7, when the light receiving signal is obtained during the light receiving element detection periods TF1 and TF2, the light emitting and receiving cells CWRij, CWRi (j + 1), CWRi ( It can be detected that the object to be detected 15 exists at a position near j + 2).

In this way, according to the image display device and the driving method of the image display device in the present modification, the threshold voltage generation unit 37 is further added from the image display device shown in FIG. The threshold voltage Vt of the comparator 351 is changed according to the display signal of each pixel, for example, if the value is high, the threshold voltage is high, and if the amount of light emitted is low, the threshold voltage is also low. In addition to the effect of the image display device shown in FIG. 15, it is possible to more accurately detect the positions of objects in contact with or in close proximity to each other.

[Modification example 4]

Next, a modification 4 common to the first and second embodiments will be described. The surface of the display unit 1 of the image display device is irradiated with ambient light in addition to the reflected light from a contacting or adjacent object. Therefore, in this modification, in the first embodiment, the comparator 35 is arranged between the light receiving signal receiver 32 and the light receiving signal holding unit 33, and further, the comparator is based on the light receiving signal VR output from the light receiving signal receiver 32. The threshold voltage generation unit 371 that generates the threshold voltage Vt at 35 is arranged. That is, the configuration is such that the threshold voltage generation unit 371 is added in the modification 2 shown in FIG. 13, and the process of removing the influence of the ambient light is performed when the light receiving signal is detected by the light emitting and receiving element EL. It is something like that.

FIG. 20 shows the overall configuration of the image display device according to the modified example 4, and corresponds to FIG. 1 in the first embodiment. In this figure, the same components as those shown in FIGS. 1 and 13 are designated by the same reference numerals, and the description thereof will be omitted as appropriate. This image display device includes a display unit 1, a display signal generation unit 21, a display signal holding control unit 22, a display signal driver 23, a light emitting side scanner 24, a light receiving signal selection scanner 31, and a light receiving signal receiver 32. , The scanner 35, the threshold voltage generation unit 371, the received signal holding unit 33, and the position detecting unit 34.

The threshold voltage generator 371 generates a threshold voltage Vt in the comparator 35 based on the received signal VR in each pixel 11 for one horizontal line output from the light receiving signal receiver 32, and outputs the threshold voltage Vt to the comparator 35. Has. Therefore, in the comparator 35, the threshold voltage Vt corresponding to the reflected light to the light emitting / receiving cell CWR in each pixel 11 can be set for each pixel.

The comparator 35 has a function of comparing the received light signal output from the light receiving signal receiver 32 with the threshold voltage signal Vt output from the threshold voltage generation unit 371 and performing A / D conversion. Further, the data converted into this digital data (comparator output signal Vc) is output to the light receiving signal holding unit 33.

FIG. 21 shows an example of the process of removing the influence of ambient light in the image display device of FIG. 20, and is composed of the processes (A) to (D). Here, one cell shown in FIG. 21 represents the pixel 11 in the display unit 1 as in FIG. 6.

First, in FIG. 21 (A), the areas other than the light receiving area 53 in the entire display unit 1 are black display areas 54A and 54B in advance, and the light emission from the light emitting / receiving cell CWR has the lowest brightness. Therefore, the light reflected from the light emitted from the light emitting / receiving cell CWR or the reflected light from a nearby object is hardly detected by the other light emitting / receiving cell CWR. In addition, while performing a series of processes to eliminate the influence of this ambient light, do not place an object that is the target of reflection in the vicinity of this image display device, and other light emitting and receiving cells CWR. It is necessary that the light detected in the above is only due to ambient light. Here, as described above, for example, the 1 horizontal line at the position indicated by the arrow P1 sequentially emits light in the direction of the scanning direction X, and the 1 horizontal line at the position indicated by the arrow P2 is the scanning direction. The line sequential light receiving operation is performed in the X direction.

Next, as shown by the 1 horizontal line at the positions indicated by the arrows P2, P5 and P3, P6 in FIGS. 21 (B) to 21 (C), the line sequential light emission operation and the line sequential operation are performed in the same manner for one screen of the display unit 1. Performs light receiving operation. At this time, the light-receiving signal detected in each light-emitting light-receiving cell CWR is output to the light-receiving signal receiver 32, and the light-receiving signal receiver outputs the light-receiving signal VR for one horizontal line to the threshold voltage generation unit 371. Then, as described above, the threshold voltage generation unit 371 generates the threshold voltage Vt in the comparator 35 based on the received light signal VR and outputs it to the comparator 35.

When the ambient light detection process for one screen is completed, the normal display operation is started at one horizontal line at the position indicated by the arrow P1 in FIG. 21 (D), and similarly, the normal display area is in the scanning direction X. As 55 expands, the normal light receiving operation starts at the 1 horizontal line at the position indicated by the arrow P2. At this time, the comparator 35 performs A / D conversion of the received signal in each pixel 11 by the threshold voltage Vt generated in consideration of the received signal VR by the ambient light obtained in (A) to (C). As it goes on, the influence of ambient light can be removed.

FIG. 22 represents a process for removing the influence of ambient light, and corresponds to FIG. 7 in the first embodiment and FIG. 14 in the second modification. Further, in this figure, as in FIG. 14, (D) the light emitting / receiving cells CWRi (CWRi1 to CWRin) for one vertical line, and (A) the data supply line DWi connected to each of these light emitting / receiving cells CWRi. , (B) Light emitting gate line G (G1 ~ Gn) and (C) Switching line S (S1 ~ Sn), (E) Data read line DRi, (F) Threshold voltage signal Vt, (G) Comparator output Signals Each signal of Vci is shown. Since the basic operation of the driving method of the image display device in this modification is the same as the operation shown in FIG. 14, the description thereof is omitted, and only the operation related to the threshold voltage generation unit 371 and the comparator 35 is described. To do.

First, as described above, in the vertical period TH1, the entire display unit 1 is the black display area 54, and (A) the signal amount on the data supply line DWi is the smallest value. Therefore, the received signal output from the (E) data read line DRi at timings t4 to t7 is considered to be due to ambient light. Next, in the vertical period TH2, the threshold voltage Vt is increased by the amount of the received signal by the ambient light detected in the vertical period TH1 in the timings t8 to t9, which is the period corresponding to the timings t4 to t7 in the vertical period TH1. It is designed to be added. In this way, the threshold value is set in consideration of the influence of ambient light.

As described above, according to the image display device and the driving method of the image display device in this modification, the threshold voltage generation unit 371 is further added in the modification 2 shown in FIG. Since the process of removing the influence of ambient light is performed when detecting the received signal, by detecting the influence of ambient light in addition to the effect of Modification 2, by detecting the object in contact with or close to it. The position can be detected more accurately.

In this modified example, the original threshold voltage Vt is a constant value, but as in the examples of FIGS. 18 and 19, the threshold voltage Vt is generated based on the display data 45. It can also be applied when it is a variable value. In that case, the threshold voltage Vt will be generated based on both the display data 45 and the received signal VR.

[Modification 5]

Next, a modification 5 common to the first and second embodiments will be described. In this modification, a plurality of verification objects simultaneously arranged at arbitrary positions are detected in the image display device, and the verification objects are also detected at arbitrary moving positions.

FIG. 23 shows the overall configuration of the image display device according to the modified example 5, and corresponds to FIG. 1 in the first embodiment. In this figure, the same components as those shown in FIG. 1 are designated by the same reference numerals, and the description thereof will be omitted as appropriate. This image display device includes a display unit 1, a display signal generation unit 212, a display signal holding control unit 222, a display signal driver 232, a light emitting side scanner 242, a light receiving signal selection scanner 312, and a light receiving signal receiver 32. , A light receiving signal holding unit 33 and a position detecting unit 34 are provided.

Here, the basic operations of the display signal generation unit 212, the display signal retention control unit 222, the display signal driver 232, the light emitting side scanner 242, and the light receiving signal selection scanner 312 are the display signal generation unit 21 and the display signal retention control in FIG. 1, respectively. Since it is the same as the unit 22, the display signal driver 23, the light emitting side scanner 24, and the received light signal selection scanner 31, the description thereof will be omitted.

The display signal generation unit 212 further includes a function of synthesizing a display signal by replacing a part of the input image data with the mark data for displaying a predetermined mark as described later, and displays the display signal holding control unit 222. The signal driver 232, the light emitting side scanner 242, and the light receiving signal selection scanner 312 receive the light emitted from the light emitting and receiving cell CWR according to the mark data by another issuing light receiving cell CWR corresponding to the position of the light emitting and receiving cell CWR. And detect the received signal. In this way, it is possible to detect an object in contact with or in close proximity from the area where a predetermined mark is displayed.

FIG. 24 shows a case where a plurality of verification objects simultaneously arranged at arbitrary positions are detected in the image display device of FIG. 23. Further, in this figure, arbitrary image data is displayed on the display unit 1 provided in the image display device 7 corresponding to the image display device shown in FIG. 23, and a plurality of predetermined marks 71 to 74 are simultaneously displayed. Represents the situation.

In this modification, the light emitted from the light emitting / receiving cell CWR in the display unit 1 is used as the light source for detecting the reflected light. Therefore, it is possible to detect the reflected light of an object that is in contact with or is close to the display unit 1 from an arbitrary position. For example, if a button-like image consisting of predetermined marks 71 to 74 is displayed at an arbitrary position on the display unit 1 and the reflected light of the object is detected from this area, the same effect as that of a touch panel can be obtained. it can. Further, in this modification, since the position of the object is detected by the received light signal reconstructed by the light receiving signal holding unit 33, it is possible to detect a plurality of positions arranged at the same time. This enables the user to detect a plurality of contacting or adjacent objects simultaneously arranged at arbitrary positions on the image display device.

FIG. 25 shows a case where a predetermined mark moves in the image display device of FIG. 23, and corresponds to the image display device 7 shown in FIG. 24. This figure shows a situation in which the mark 74 is moving as shown by the arrow 741 among the plurality of predetermined marks 71 to 74 displayed on the image display device 7 shown in FIG. 24. Further, in this figure, the same components as those shown in FIG. 24 are designated by the same reference numerals, and the description thereof will be omitted as appropriate.

In this modification, the display signal generation unit 212 has a function of synthesizing a display signal by replacing a part of the input image data with the mark data for displaying a predetermined mark as described above. Here, when the input image data is moving image data composed of a plurality of frames, the display signal generation unit 212 marks a part of the input image data at different positions for each frame according to the moving image data. If you replace it with data, for example, you can move the button-like part as shown in Fig. 25, display the button-like part in the video part, or if necessary, the button-like part. Can be displayed or erased.

This enables the user to detect an object that is in contact with or is close to the image display device even at an arbitrarily moving position. Further, since what kind of image is displayed is determined by the display signal generation unit 212, when the image for the button consisting of a predetermined mark is not displayed, the data of the result of the position detection is used. If it is not done, it is possible to prevent false detection.

Although the present invention has been described above with reference to some embodiments and modifications, the present invention is not limited to these, and various modifications are possible. For example, in the above embodiment, the display operation and the light of the adjacent light emitting pixel are detected by repeating "light reception light emission extinguishing" as the operation of each pixel, or by repeating "light reception light emission". Although the object detection operation is performed in parallel, the light of the adjacent light emitting pixel can be detected by repeating "light emission light reception extinguishing", for example.

<figref num="1">It is a block diagram which shows the whole structure of the image display device which concerns on 1st Embodiment of this invention.</figref><figref num="2">It is a block diagram which shows an example of the structure of the display part in FIG.</figref><figref num="3">FIG. 5 is a cross-sectional view schematically showing an example of an arrangement configuration of light emitting / receiving cells in the display unit of FIG.</figref><figref num="4">It is a circuit diagram which shows the structure of the light emitting and receiving cell in FIG.</figref><figref num="5">It is a schematic diagram which shows an example of the process of detecting the object to be detected in the image display device of FIG.</figref><figref num="6">It is a figure which shows an example of the line sequential light emitting operation and line sequential light receiving operation in the image display device of FIG.</figref><figref num="7">It is a timing diagram of the process of detecting the object to be detected in the image display device of FIG.</figref><figref num="8">It is a block diagram which shows the whole structure of the image display device which concerns on 2nd Embodiment of this invention.</figref><figref num="9">It is a figure which shows an example of the line sequential light emitting operation and line sequential light receiving operation in the image display device of FIG.</figref><figref num="10">It is a timing diagram of the process of detecting the object to be detected in the image display device of FIG.</figref><figref num="11">It is a block diagram which shows the whole structure of the image display device which concerns on modification 1.</figref><figref num="12">It is a timing diagram of the process of detecting the object to be detected in the image display device of FIG.</figref><figref num="13">It is a block diagram which shows the whole structure of the image display device which concerns on modification 2.</figref><figref num="14">It is a timing diagram of the process of detecting the object to be detected in the image display device of FIG.</figref><figref num="15">It is a block diagram which shows the other whole configuration example of the image display device which concerns on modification 2.</figref><figref num="16">It is a distribution figure which shows an example of the signal amount of the received light signal.</figref><figref num="17">It is a schematic diagram when the threshold value is changed in the distribution of the signal amount of the received signal of FIG.</figref><figref num="18">It is a block diagram which shows the whole structure of the image display device which concerns on modification 3.</figref><figref num="19">It is a timing diagram of the process of detecting the object to be detected in the image display device of FIG.</figref><figref num="20">It is a block diagram which shows the whole structure of the image display device which concerns on modification 4.</figref><figref num="21">It is a schematic diagram which shows an example of the process which removes the influence of ambient light in the image display apparatus of FIG.</figref><figref num="22">It is a timing diagram of the process which removes the influence of ambient light.</figref><figref num="23">It is a block diagram which shows the whole structure of the image display device which concerns on modification 5.</figref><figref num="24">It is a schematic diagram in the case of detecting a plurality of verification objects simultaneously arranged at arbitrary positions in the image display device of FIG. 23.</figref><figref num="25">It is a schematic diagram when a predetermined mark moves in the image display device of FIG. 23.</figref>

Code description

1,101 ... Display, 11 ... Pixels, 12 ... Transparent substrate, 13 ... Partition, 15 ... Detectable object, 21,212 ... Display signal generator, 22,222 ... Display signal retention Control unit, 23,232 ... display signal driver, 24,242 ... light emitting side scanner, 31,311,312 ... light receiving signal selection scanner, 32 ... light receiving signal receiver, 33 ... light receiving signal holding part, 34 ... position Detector, 35,351 ... Scanner, 36 ... Shift register, 37,371 ... Threshold voltage generator, 41 ... Light emission timing control signal, 42 ... Light reception timing control signal, 43 ... Light reception Block control signal, 45 ... display signal, 51 ... light emitting area, 52 ... non-light emitting area, 53 ... light receiving area, 54 ... black display area, 55 ... normal display area, 61 ~ 64 ... Received signal detection level, 65 ~ 67 ... Received signal detection area, 7 ... Image display device, 71 ~ 74 ... Mark, 741 ... Mark movement status, CWR ... Light emitting / receiving cell, G ... light emitting gate line, S ... switching line, DW ... data supply line, DR ... data read line, LW, LW1 ... emission light, LR1 ... reflection Light, EL ... light emitting / receiving element, C ... capacitor, R ... resistance, SW1 ... 1st switch, SW2 ... 2nd switch, SW3 ... 3rd switch, I1 ... Display signal current path, I2 ... Receive signal current path, X ... Scan direction, P1, P2, P3, P5, P6 ... Line position during scanning, TH1, TH2 ... Vertical Period, TW ... light emission period, TR ... light receiving period, TF1, TF2 ... light receiving signal detection period, t0 ~ t14 ... timing, Vt ... threshold voltage signal, Vc ... comparator Output signal, VR ... Received signal.