Light receiving device of distance measuring apparatus

Description: TECHNICAL FIELD [Detailed description of the invention]

【0001】

[Industrial application field]

The present invention relates to a light receiving device of a distance measuring device, and more particularly to an improvement of a light receiving device provided with an erroneous distance measuring preventing means applied to a distance measuring device such as an active autofocus mechanism of a camera.

【0002】

[Conventional technology]

FIG. 5 shows the configuration of a light receiving device using a pair of light receiving elements for distance measurement in the active autofocus mechanism as this type of distance measuring device according to the conventional example, and the mode of receiving normal reflected light to the light receiving device. It is a conceptual diagram to explain, FIG. 6 is a conceptual diagram explaining the light receiving mode of the reflected light which caused a chip in the light receiving device in the same as above, FIG. 7 is a chip in the light receiving device in the same as above. It is a conceptual diagram explaining the light receiving mode of the apparent reflected light brought about by the light receiving of the reflected light. Further, FIG. 8 is an explanatory diagram showing a calculation method at the time of distance measurement in the active autofocus mechanism in the same conventional example.

【0003】

In each of these conventional examples, reference numeral 10 indicates a light receiving device in the active autofocus mechanism, and CH1 and CH2 are a pair of quadrangular light receiving elements arranged adjacent to each other constituting the light receiving device 10, and A1 , A2 are the detection outputs of the reflected light received by each of these light receiving elements CH1 and CH2. Further, 11 is normal reflected light received by each of the light receiving elements CH1 and CH2, 12 is similarly received reflected light with a chip, and 13 is apparently brought about by the light received by the reflected light 12 with the same chip. It is the normal reflected light above.

【0004】

In the active autofocus mechanism having the above-mentioned conventional configuration, as shown in FIG. 5, the detection output of the reflected light received by each of the light receiving elements CH1 and CH2 of the light receiving device 10 is calculated by the calculation method shown in FIG. By detecting this as the area ratio of each reflected light, it is used for one calculation data for distance measurement.

【0005】

That is, according to this conventional distance measuring means, as seen in FIG. 5, when the normal reflected light 11 is evenly received by each of the light receiving elements CH1 and CH2, the areas of both are measured by the calculation method of FIG. The ratio is CH1: CH2 = 1: 1 (Fig. 5) When the normal reflected light 11 is received only for one of the light receiving elements CH1 side, the area ratio of the two is similarly increased. CH1: CH2 = 1: 0 It is detected without matching like.

【0006】

[Problems to be Solved by the Invention]

However, in this conventional distance measuring means, for example, as shown in FIG. 6, the reflected light received at the time of distance measurement has a chip on the light receiving element CH2 side, and the chipping occurs only on the light receiving element CH1 side. When the generated reflected light 12 is received, the area ratio of the two becomes CH1: CH2 = 1: 0 (Fig. 6) As shown in Fig. 7, it seems that the normal reflected light 11 was received only on the corresponding light receiving element CH1 side. In the same state, in other words, it is similar to the apparent normal reflected light 13 brought about by the chipped reflected light 12, and the calculation result of the area ratio of both is CH1: CH2 = 1: 0 (Fig. 7) Finally, the detection result on the light receiving element CH1 side that received the light is either due to the normal reflected light 11 or apparently due to the normal reflected light 13. There was a problem that it could not be determined whether it was a thing.

【0007】

The present invention has been made in order to solve such a conventional problem, and the purpose of the present invention is to detect ordinary reflected light as the original ordinary reflected light and to lack the ordinary reflected light. The reflected light that produced the light is not detected like the normal reflected light that appears, but can be accurately detected as the reflected light that is chipped. It is to provide a light receiving device.

【0008】

[Means for solving problems]

In order to achieve the above object, the light receiving device of the distance measuring device according to the present invention is a set of light receiving elements by dividing each pair of light receiving elements arranged adjacent to each other under the same conditions. If the area ratio of the reflected light between the light receiving elements does not match, the presence or absence of missing reflected light is detected from the area ratio of the reflected light between the light receiving elements. is there.

【0009】

That is, the present invention has a pair of light receiving elements (CH1) and (CH2) arranged adjacent to each other constituting the light receiving device (10), and calculates the light receiving output of each light receiving element (CH1), (CH2). Then, in the distance measuring method for detecting whether or not the area ratios of the two are the same, each of the pair of light receiving elements (CH1) and (CH2) is divided into a plurality of pieces under the same conditions, respectively. Reflection obtained by calculating the light receiving output between each light receiving element (CH1a), (CH1b) and each light receiving element (CH2a), (CH2b). If the area ratios of the light do not match, the light receiving output between each light receiving element (CH1a) and (CH1b) and between each light receiving element (CH2a) and (CH2b) is set. It is a light receiving device of a distance measuring device characterized in that the presence or absence of lack of reflected light can be detected by the area ratio of reflected light obtained by calculation.

【0010】

[Action]

Therefore, in the present invention, each pair of light receiving elements (CH1) and (CH2) is divided into a plurality of light receiving elements (CH1a) and (CH2) under the same conditions to form a set of each light receiving element (CH1a), (CH1b). ) And each light receiving element (CH2a), (CH2b), and when the area ratio of the reflected light between the light receiving elements (CH1) and (CH2) does not match, each of these light receiving elements (CH1) and Since the area ratio of the reflected light between each light receiving element (CH1a) and (CH1b) constituting (CH2) and between each light receiving element (CH2a) and (CH2b) is obtained, 1 Each pair of light-receiving elements (CH1) and (CH2) can detect the mutual area ratio due to normal reflected light, and a set of each light-receiving element (CH1a) and (CH1b), and each light-receiving element. Depending on the parts (CH2a) and (CH2b), the presence or absence of missing reflected light can be detected.

【0011】

[Example]

Hereinafter, examples of the light receiving device of the distance measuring device according to the present invention will be described in detail with reference to FIGS. 1 to 4.

【0012】

FIG. 1 shows the configuration of a light receiving device using a pair of light receiving elements arranged adjacently for distance measurement in an active autofocus mechanism to which an embodiment of the present invention is applied, and the light receiving device. FIG. 2 is a conceptual diagram for explaining a normal light receiving mode for each light receiving element, FIG. 2 is a conceptual diagram for explaining a normal reflected light receiving mode for only one light receiving element in the same embodiment, and FIG. 3 is a conceptual diagram. , Is a conceptual diagram illustrating a mode of receiving reflected light in which only one light receiving element in the same embodiment is chipped. Further, FIG. 4 is an explanatory diagram showing a calculation method at the time of distance measurement in the active autofocus mechanism in the same embodiment. Here, in each of these Examples, the same reference numerals as those of the above-mentioned conventional Examples indicate the same or corresponding portions.

【0013】

In each of these Examples, reference numeral 10 indicates a light receiving device in the active autofocus mechanism, and CH1 and CH2 are a pair of light receiving elements in a rectangular shape arranged adjacent to each other constituting the light receiving device 10, CH1a, CH1b, CH2a, and CH2b are each pair of light receiving elements CH1 and CH2, each of which is formed by dividing the square shape of each pair of light receiving elements CH1 and CH2 into two diagonally on the same diagonal. A1b, A2a, and A2b are the light receiving outputs of the reflected light received by each of the light receiving element units CH1a, CH1b, CH2a, and CH2b of the pair. Further, 11 is normal reflected light received by each of the light receiving elements CH1 and CH2, and 12 is similarly received reflected light with a chip.

【0014】

Therefore, in the case of the active autofocus mechanism according to the above-described embodiment, as shown in FIG. 1, the reflected light received by the light receiving elements CH1 and CH2 of the light receiving device 10 at the time of distance measurement, and by extension, the light received by each of them. The reflected light received by each of the light receiving element units CH1a, CH1b and CH2a, CH2b of each set constituting the elements CH1 and CH2 is calculated as the light receiving outputs A1a, A1b and A2a, A2b shown in FIG. It is calculated as follows by the method, and by detecting this as the area ratio of each reflected light, the detection result is used as one calculation data for distance measurement.

【0015】

That is, according to the distance measuring means of this embodiment, as seen in FIG. 1, when the normal reflected light 11 is evenly received by each of the light receiving elements CH1 and CH2, each of them is performed by the calculation method of FIG. The area ratio of the light receiving element CH1a, CH1b and CH2a, CH2b is CH1a + CH1b: CH2a + CH1b = 1: 1 (Fig. 1) When the normal reflected light 11 is received only on one of the light receiving elements CH1 side, the area ratios of the light receiving element portions CH1a, CH1b and CH2a, CH2b are similarly increased. , CH1a + CH1b: CH2a + CH1b = 1: 0 (Fig. 2) It will be detected without matching like.

【0016】

Then, when the area ratios do not match, the received reflected light is the normal reflected light 11, or the reflected light 12 in which a chip is formed, that is, the apparent normal light in the above-mentioned conventional example. In order to determine whether the light is reflected light 13, the light receiving outputs A1a and A1b in each of the light receiving element units CH1a and CH1b of the set are recalculated for the light receiving element CH1 that generated the light receiving output in this case. , Each area ratio of each CH1a: CH1b = 1: 1 (corresponding to Fig. 2) If this is the case, it can be determined that this is the case where the normal reflected light 11 is received only for the light receiving element portions CH1a and CH1b on the corresponding light receiving element CH1 side, and the area ratio of each is , CH1a: CH1b = 0: 1 (corresponding to Fig. 3) If this is the case, it can be determined that this is the case where the chipped reflected light 12 is received only for the light receiving element portion CH1b adjacent to the non-corresponding light receiving element CH2 on the corresponding light receiving element CH1 side. Finally, in this way, it is extremely easy to determine whether the received reflected light is the normal reflected light 11 or the chipped reflected light 12.

【0017】

In the above-described apparatus, each pair of light receiving elements CH1 and CH2 are formed in a square shape, and a pair of light receiving element portions CH1a, CH1b and CH2a, CH2b are formed. Each of them is formed by dividing the square shape into two diagonally on the same diagonal line, but it is not necessarily limited only to this division mode, and by dividing into a plurality of more than one in an arbitrary direction. Of course, the same action and effect can be obtained.

【0018】

[Effect of the invention]

As described above, as described in detail by the embodiment, according to the method of the present invention, the light receiving device is composed of a pair of light receiving elements arranged adjacent to each other, and the light receiving output of each of these light receiving elements is calculated. In the distance measuring method for detecting whether or not the area ratios of the two are the same, each pair of light receiving elements is divided into a plurality of pieces under the same conditions, and one light receiving element portion and the other light receiving element are respectively divided into a plurality of light receiving elements. When each light receiving element is formed and the area ratio of the reflected light obtained by calculating the light receiving output between the light receiving elements does not match, one of the light receiving elements and the other By calculating each light receiving output between the light receiving element units, the area ratio of each reflected light between them can be obtained, and the presence or absence of missing reflected light can be detected. Each light receiving element of the above can detect the mutual area ratio due to the normal reflected light, and each set of light receiving elements constituting each light receiving element can detect the presence or absence of lack of reflected light. It is possible to demonstrate the excellent feature that the distance measurement operation with high accuracy becomes possible.

[Simple explanation of drawings]

[Figure 1]

It is a conceptual diagram explaining the structure of the light receiving device of the active autofocus mechanism to which one Example apparatus of this invention was applied, and the light receiving mode of ordinary reflected light.

[Figure 2]

FIG. 5 is a conceptual diagram illustrating a mode of receiving normal reflected light with respect to only one light receiving element of the light receiving device of FIG.

[Fig. 3]

FIG. 1 is a conceptual diagram illustrating a mode of receiving reflected light in which only one light receiving element is chipped.

[Fig. 4]

It is explanatory drawing which shows the calculation method at the time of distance measurement in the active autofocus mechanism of FIG.

[Fig. 5]

It is a conceptual diagram explaining the structure of the light receiving device of the conventional active autofocus mechanism, and the light receiving mode of the normal reflected light with respect to this light receiving device.

[Fig. 6]

It is a conceptual diagram explaining the light receiving mode of the reflected light which caused the chipping with respect to the light receiving device of FIG.

[Fig. 7]

It is a conceptual diagram explaining the reception of the apparent reflected light brought about by the reception of the reflected light which caused the chipping to the light receiving device of FIG.

[Fig. 8]

It is explanatory drawing which shows the calculation method at the time of distance measurement in the active autofocus mechanism of FIG.

[Explanation of symbols]

10 Light receiving device with active autofocus mechanism CH1, CH2 Each individual light receiving element consisting of a pair CH1a, CH1b Each set of light receiving elements that make up one of the light receiving elements CH2a, CH2b One set of each light receiving element that constitutes the other light receiving element A1a, A1b Light-receiving output of each light-receiving element A2a, A2b Light receiving output of each other light receiving element 11 Normal reflected light 12 Chipped reflected light