Image recognition sensor device has 2 sets of sensor elements using visible and IR light, e.g. for providing video telephone image and user identification image

The invention relates to a sensor arrangement for image recognition according to the preamble of claim 1. It is known in egg nem automobile to arrange a digital camera to a take picture of the driver, wherein the set of the camera made image of the driver ausgewer in different ways tet can be.

A possible technical application is the camera to connect to a video phone, a videophone About to allow transmission from the motor vehicle.

Another industrial application is in a fatigue recognition in which while driving images of the driver's face be included; for example, from the eyelid frequency of driver fatigue condition is derived.

Finally, the image captured by the camera of the Driver for the identification of the driver used who to, for example, the use of the motor vehicle only a specific person with a predetermined physiognomy release, while the motor vehicle with other people is locked.

The problem here is that both the Müdigkeitser identification as well as in the identification of people as possible must prevail precisely defined lighting conditions, a Misrecognition to ver due to fluctuating light conditions avoid. It is therefore known, drowsiness detection and to identify a person to use an infrared camera, so precisely defined by Infrared Illuminator lighting processing conditions can be created.

The disadvantage here is that in addition to the day lichtempflindlichen camera for videophone infrared camera for the fatigue detection and the Personenindentifi cation is required.

EP 0605259 A2 discloses an optical sensor arrangement as Be was part of a copying machine known that both Sensorele elements for visible light and sensor elements for Infra having red light. The luminance of the object he However, in this case follows a broad band by a halogen lamp, the both the sensor elements for visible light as well as the Sensor elements for infrared light controls. In the known Sensor arrangement are therefore optical filters for image separation required.

The invention is therefore based on the object, an optical to provide sensor arrangement for image recognition that a single camera recording under precisely defined Lichtver ratios, for example, a drowsiness detection system or a Personal identification, and the other recording norma allows ler images, for example, a videophone.

The object is, starting from a known Sensoranord arrangement according to the preamble of claim 1 by the characterizing features of claim 1.

The invention comprises the general technical teaching in egg ner sensor arrangement for image recognition with several rasterför mig arranged optical sensor elements not only sensor elements provide the visible light in the wavelength on gene region to address, but also sensor elements on responsive light in the visible wavelength range. The responsive to light in the visible wavelength range Sensors here serve to receive a normal monochro men or multicolor image, for example, for a Bildte lephone while to light in the invisible Wellenlän gene region responsive sensor elements are capable of a the driver image under precisely defined lighting conditions take, as the disturbing influence of Umgebungsbeleuch tion is omitted.

Preferably, it is not in the on light in the visible wavelength range responsive sensor elements the second type of infrared sensor elements, but can the sensor elements of the second type on the light in other responsive wavelength ranges. It is only important that the sensor elements of the second type, the normal lighting not detect so artificial by Lighting defined light conditions for fatigue detection and the identification of people to be created can.

The individual sensor elements may for example consist of a photosensitive cell consist, on which a color filter is attached, wherein the on the sensor elements of the first Type patch color filter is preferably in the red, green and Blue-sensitive area, while on the Sensorele elements of the second type mounted color filter preferably in the infrared region are permeable.

Preferably, the sensor array has a plurality of grid-like juxtaposed modules of at least one Sen sensor element of the first type and at least one sensor element of the second type. Individual modules can, for example, be square and three sensor elements of the first type show that in light of the three primary colors red, green and appeal blue, and a sensor element of the second type, responsive to light in the infrared range.

The sensor elements of the first type and the sensor elements of the the second type can use a common electrical From his gang, said separation of the various Images made by a separate hardware or software. It but it is also possible that the sensor elements of the first Type connected to a first electrical signal output are, while the sensor elements of the second type with a second electrical signal output are connected, so that the various images on the two signal outputs ge separates are provided.

In the preferred embodiment, the distribution density of the sensor elements of the first type is substantially greater than the Distribution density of the sensor elements of the second type. Increase However, re sensor elements of the first type usually form along a grid point, while each sensor element of the second type preferably a separate screen dot forms, so that the grid density (pixel density) for both types of Sensor elements is preferably the same size.

Further, according to the invention for illuminating the Bildob ject at least a headlight provided with the light a wavelength emitted to which only the sensor elements address of the second type. This is important in order for the Personal identification and possibly also for the Müdigkeitser identifier defined light conditions are created currency rend the spotlight detection of the normal picture at example for the videophone must not interfere. To this end, can the headlights, for example from one or more Infrared LEDs exist.

In addition, it is provided according to the invention that the Sensor elements are connected to a selection unit which either one of the two images selecting, said from selection unit is connected to the headlights to the Akti vation of the headlight with the selection of the sensor element to synchronize. The lighting of the image object with Light in the visible wavelength range is therefore carried out only when the selection unit and the sensor elements of the second type selects, whereas the headlight while the remaining time can be switched off.

In a further variant of the invention is additionally against seen that the sensor elements with a Belichtungssteue tion are connected to the exposure time of Sensorelemen te adjust. Preferably, the exposure control two shots with different exposure times on. This is advantageous since, for example when shooting an image on a video phone a longer exposure time is required, whereas for fatigue detection very short exposure times are useful.

According to a variant of the invention is a scanning unit provided that the Bil generated by the sensor elements scans at a predetermined frame rate. In front preferably scans the scanning alternately in a ers th sampling both the sensor elements of the first type as well as the sensor elements from the second type, while in a subsequent second scanning step only the Sensorele elements of the second type are scanned. In this way he provide for the normal RGB image on the one hand and the IR Image on the other hand, different frame rates, which the technical requirements in the above-described is the various technical applications. Typi cal frame rates here are 50 Hertz for the IR image and 25 Hertz for the RGB image.

It should also be mentioned that the sensor of the invention arrangement, for example in mobile devices like can be used for example in mobile phones. In particular ticular in UMTS mobile phones is a use of the inventions to the invention the sensor arrangement advantageously. Allowing the Sensor assembly according to the invention in a mobile phone at for example the user identification by an infrared patterns of the user defined in IR Lighting conditions is received. The use of the Mobile phone is then only released when the user identification shows that the user is authorized. Furthermore, allowing the use of the invention Sen soranordnung in a mobile phone in low Lichtver and fair image transfer using an Infra rotbildes.

Other advantageous variants and refinements of the inventions tion are characterized in the dependent claims and together with the below description of the preferred Embodiment using the figures explained. It show:

<b>Fig.</b> 1, a sensor arrangement according to the invention as a block circuit diagram,

<b>Fig.</b> 2a a raster mask with multiple sensor elements and

<b>Fig.</b> 2b an alternative raster mask.

In the <b>Fig.</b> 1 sensor arrangement illustrated is in a Passenger vehicle for detecting the driver's face. For this purpose, the sensor arrangement an optical sensor <b>1</b> on which in the motor vehicle, for example in the umbrella organization clothing can be arranged and on the driver's face is addressed. The optical sensor<b>1</b> has a plurality of CCD sensor elements on the raster-ver in a plane disposed shares, as in <b>Fig.</b> 2a is shown. The individual sensor elements are in the form of a grid Anord erly <b>Fig.</b> 2a arranged in rows and columns, in the odd lines alternately Sensorele elements are arranged on red and green light, speaking, whereas in the even lines Sensorele elements are arranged alternately on and infrared light appeal blue light. The grid-like arrangement of<b>Fig.</b> 2a therefore consists of a plurality of square Modules which two sensor elements of a visible light responsive first type and a sensor element on one Infrared light responsive second type included.

On the output side of the sensor <b>1</b> with a control and Auswer processing unit <b>2</b> connected, which has several functions, as described in is described below.

Firstly, the control and evaluation unit operates <b>2</b> as Scanner and scans the individual sensor elements to from each other, wherein in each of the modules, the first sensor elements of the first type, then the sensor element the second type is scanned.

Furthermore, the control and evaluation unit is used <b>2</b> as from selection unit and the output side separately normal Colour RGB and an infrared image IR ready.

Finally, the control and evaluation unit <b>2</b> on the In person, during the identification of people and during Mü produce digkeitserkennung defined lighting conditions. For this, the control and evaluation unit <b>2</b> ausgangssei tig two headlamps <b>3</b>. <b>4</b> connected, the light in the Inf rarotwellenlängenbereich imitate toward the driver. The headlights <b>3</b>. <b>4</b> consist of infrared LEDs that to the sensor <b>1</b> are adjacent.

On the output side, the control and evaluation unit <b>2</b> With a fatigue sensor <b>5</b>, A videophone <b>6</b> and a Ge face recognition unit <b>7</b> connected, for convenience, are only shown schematically.

<b>Fig.</b> 2b shows an alternative arrangement of a grid-like distributed sensor elements, where the individual sensor elements each strip-shaped and arranged.

The invention is not limited to the above-described BE Preferred embodiment limited. Rather, it is a Plurality of variants and modifications conceivable that of the make inventive idea and therefore also in the scope covered.