JPH02208508A - Distance measuring test of distance measuring module for automatic focusing - Google Patents

Abstract

PURPOSE:To enable a smaller size and a saving of space of a distance measuring system to be attained by moving a spot beam image projected onto a screen from infrared rays emitting body along the length of a base line between light emitting and receiving sections of a distance measuring module. CONSTITUTION:As an infrared rays emitting body 12 is turned in a direction of the arrow centered on a pivot 13 thereof, a spot beam image projected onto a screen 11 from the emitting body 12 is moved horizontally to form virtual distance information on the screen. Therefore, when a light receiving section 3 of a distance measuring module 1 reads a projection spot beam image shifted on the screen 11 corresponding to a real distance from a reference line to be formed on a light receiving array surface thereof, the module 1 regards this image as a beam image reflected from a reflecting plate or the like as if located at a real distance to perform a measuring of a distance. Then, a distance data measured by the module 1 is compared to a subject list preset corresponding to a deviation value thereby enabling the checking of the results of a distance measurement of the module 1.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a distance measurement test method for an autofocus distance measurement module, in particular, a method for emitting a modulated infrared beam toward a subject;
The present invention relates to a distance measurement test method for an autofocus distance measurement module that uses active triangulation to measure the distance to an object from its reflection angle.

(Prior art) In an infrared active type autofocus distance measurement module, it is necessary to check whether or not it actually performs correct distance measurement.3 Figure 7a shows a conventional autofocus distance measurement module. It is a principle block diagram of a distance measurement test device.

In the figure, reference numeral 1 denotes a triangular distance measuring module (hereinafter simply referred to as a distance measuring module) for active autofocus to be tested for distance measurement, and a light emitting section 2 consisting of an infrared light emitting element and a projection lens, and a light emitting section 2 that illuminates the subject. The light emitting unit 2 and the light receiving unit 3 are separated by a distance xO. This distance Xo becomes the baseline length.

The distance measurement module 1 described above is positioned and set at a predetermined position of the distance measurement test unit 4°. The distance measurement test unit 4 includes a plurality of reflecting plates 51.5□, 5.5 for providing distance information in the irradiation direction of the infrared light beam from the light emitting unit 2 of the distance measurement module 1. , -..., and each of the reflecting plates 5. ．．
5. ．． 5. ．． ... is the predetermined actual distance I21 from the ranging module 1. β1+121... is arranged so that it can be taken in and taken out.

In the distance measurement test unit configured as described above, when checking whether the distance measurement operation of the distance measurement module 1 is performed normally, for example, distance 2. To obtain the measured distance data of the distance measurement module 1 for the actual distance of 5. Reflect the spot beam. The direction is the 0 reflection plate that projects the light.5. Spot light image projected on 6. (See FIG. 7) is reflected by the reflecting plate 51 and formed into an image on the light receiving element array of the light receiving section 3. In the light receiving section 3, a spot light image 6. is placed on any part of the light receiving element array. The reflection plate 5. Measure the distance to. and,
Measurement data calculated by the ranging module 1 and the reflector 5. By comparing the actual path ii1β1 up to the point ii1β1, it is checked whether the distance measuring module 1 is performing the distance measuring operation correctly.

In addition, reflective plates 5□, 53. Distance I2. ,
I2. .

. . is measured in the same manner as described above. At this time, the projected spot light images 6, . 6. ... (see Figure 7) appears as a difference in the imaging position of the light-receiving element array of the light-receiving section 3, which converts this into an electrical signal and sends it to the calculation section. By manually calculating the distance to the reflectors 5 , 5 , . . . and comparing the calculated measurement data with the actual distance to each reflector 5 □, 5 a, , check whether the distance measuring module l is performing the distance measuring operation correctly.

(Problem to be Solved by the Invention) In the conventional ranging test method for ranging modules as described above, distance information for ranging module l is arranged in the direction of reflection of the infrared spot beam of ranging module l by actual distance. Since it is given by multiple reflections @51°52,..., the distance measurement check system of the distance measurement module requires the actual distance and space to be measured, which increases the size of the test equipment. In particular, distance measuring modules for cameras equipped with a zoom mechanism require a distance of 10 meters or more, making the test equipment even larger and occupying more space. There is a problem in that it is extremely disadvantageous to incorporate the test device into a camera assembly line.

The present invention has been made in order to solve the above-mentioned problems, and provides a distance measurement test method for an autofocus distance measurement module that facilitates miniaturization and space saving of a distance measurement test system. With the goal.

(Means for Solving the Problems) A distance measurement test method for an autofocus distance measurement module according to the present invention involves directly facing a screen at a predetermined distance from the distance measurement module to be tested, and using a separate infrared light emitting device. The spot beam image to be projected onto a plane at a real distance from the body is replaced on the screen, and the spot beam image containing the replaced virtual distance information is focused on the light receiving section of the distance measuring module. It is designed to measure distance.

(Function) When the spot beam image projected from the infrared light emitter onto the screen is moved in the baseline length direction between the light emitting part and the light receiving part of the ranging module, the amount of deviation of the spot beam image from the reference point becomes the actual distance. This becomes virtual distance information to simulate. Therefore, if the spot beam image projected on the screen is focused on the light receiving part of the distance measurement module, the distance measurement module will detect it as if it were a beam image reflected from the actual distance, thereby measuring the distance corresponding to the actual distance. will be carried out.

Therefore, in the present invention, actual distance is not required for the distance measurement test of the distance measurement module, and the test system can be made smaller and space-saving.

(Example) An embodiment of the method of the present invention will be described below based on the drawings.

FIG. 1 is a principle block diagram showing an example of a distance measurement test system for an autofocus distance measurement module according to the method of the present invention.

In the figure, the distance measuring module l to be tested is equipped with an infrared light emitting section 2 and a light receiving section 3 as in the conventional case, and the light emitting section 2
0 The floodlight window is a shielding member! 0.

Further, the desired distance (
For example, a screen 11 that forms virtual distance information is arranged at 1 m).

On the distance measuring module 1 side facing the screen 11, an infrared light emitter 12 that provides virtual distance information is arranged at a desired distance. This infrared light emitter 12 has the same structure and characteristics as the light emitting section 2 of the distance measuring module 1, and has a structure that allows it to rotate about a pivot 13 in the direction of the arrow. Therefore, by rotating the infrared emitter 12 in the direction of the arrow around the pivot 13, the spot beam 12a projected from the infrared emitter 12 onto the screen 11 is directed in the horizontal direction of the screen 11, that is, the light emitted from the distance measuring module l. Baseline length X between section 2 and light receiving section 3. It is possible to scan in a direction parallel to the

Next, the operation of this embodiment configured as described above will be explained.

First, prior to the operation of this embodiment, the principle of replacing the actual distance to the distance measuring module l with a virtual distance will be described.

As shown in FIG. 2, the light emitting section 2 or the light receiving section 3 of the distance measuring module l. Set the virtual distance to the position of, and
Actual distance g,,9. ．． ．． I2. When the spot beam images SB, SB, SB3 projected from the light emitting unit 2 on the upper plane are replaced with the virtual distance ML, the virtual distance seen from the light receiving unit 3 is replaced with the upper plane. Each actual distance β1 above. β2. Displacement beam image S B ′, corresponding to β1.

SB'+ and SB' are as shown in FIG. 2, and their front view is shown in FIG.

This is a virtual distance. displacement beam image SB' at
, SR', SB', actual distance beam images SB, SB
, SB, the actual distance is 1! ,,E,,β
This indicates that 3 can be simulated. When the relationship between the replacement distance L0 and the shift amount X is summarized with respect to the actual distance 12z, it becomes as shown in FIG. 4. That is, θ=tan-' (X o/L o)----・= (
1) X A = L 2・sinθ ・・・・・・−・
−・・・・・・・・・・・・(2) r=Lo Htan
(θ, /2)−−−−−−(3). Also, the actual road 1tlI2. Upper beam (lisB, virtual distance 1iiL, upper replacement beam image S B', and deviation amount XA
The relationship is shown in FIG.

However, Lo = set virtual distance xo two base line length (distance measurement module specified value) θ. : Projection angle (
Distance measurement module specified value) I22: Actual distance Virtual distance calculated from the above formula. Radius r of the beam image on the top
and the deviation NxA can be calculated.

Then, the amount of deviation xA becomes a parameter representing the actual distance.

Next, the operation of this embodiment will be described based on the above principle.

When the infrared emitter 2 and its axis 13 are rotated in the direction of the arrow in Fig. 1, the spot beam image projected from the infrared emitter 12 onto the screen 11 moves horizontally as shown in Fig. 3. and this causes screen 11
virtual distance information will be formed on the top. Therefore,
If the light receiving unit 3 of the distance measuring module 1 reads a projected spot beam image shifted from the reference 1a14 (see FIG. 3) on the screen 11 in accordance with the actual distance, and forms the image on the light receiving array surface, distance measurement can be performed. Module 1 regards it as a spot beam image reflected from a reflector, etc. at an actual distance,
This allows distance measurement to be performed. The distance measurement result of the distance measurement module 1 can be checked by comparing the distance data measured by the distance measurement module 1 with a target table prepared in advance corresponding to the deviation amounts x and l.

In this embodiment as described above, virtual distance information is projected onto the screen 11 as a sub-beam image from the distance measuring module l and another infrared light emitter 12.
The light receiving section 3 of the distance measuring module 1 reads this virtual distance information to measure the distance corresponding to the actual distance. There is no need to measure the actual distance, for example, and only the screen 11, which is about 1 meter away, is required.As a result, the distance measurement test system can be made smaller and save space, and it can also be easily incorporated into the camera assembly line. Become.

Next, another embodiment of the distance measurement test system according to the present invention will be described with reference to FIG.

FIG. 6 shows a schematic configuration diagram of a distance measurement test system according to another embodiment, and the same parts as in FIG. 1 are given the same reference numerals.
The explanation thereof will be omitted, and the parts different from those in FIG. 1 will be emphasized.

The difference between the figure and FIG. 1 is that the screen 11 is formed from a transparent or semi-transparent member, and the infrared light emitter 1
2 is placed at a position opposite to the distance measuring module l to be tested with the screen 11 in between, at an equal distance L0 apart, and the light emitting body 12 is installed on a moving table 15, and is driven to emit light by a driving means such as a step motor. The body 12 is made movable in the horizontal direction parallel to the screen 11.

In this embodiment, the longitudinal distance of the ranging test system is twice that of the case of FIG. 1, but the effect is the same as that of FIG.

(Effects of the Invention) As described above, according to the present invention, virtual distance information is displayed on the screen that is directly facing the distance measuring module under test at an arbitrary distance from the infrared light emitter in correspondence with the actual distance. Since the distance measurement module measures the distance based on this beam image by projecting a sub-front beam image including the beam image, there is an effect that the distance measurement test system can be made smaller and space-saving.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram showing an example of a test system to which the distance measurement test method for a distance measurement module according to the present invention is applied; FIG. 2 is an explanatory diagram showing the principle of virtual distance replacement according to the method of the present invention;
FIG. 3 is a front view of the beam image in FIG. 2, FIG. 4 is an explanatory diagram showing the relationship between displacement distance and deviation amount in the present invention,
FIG. 5 is an explanatory diagram showing the deviation state of the beam image in FIG. 4, FIG. 6 is a schematic configuration diagram showing another embodiment of the distance measurement test system to which the method of the present invention is applied, and FIG. 7(a) is The schematic configuration diagram of the conventional distance measurement test system, Figure 7(b), is similar to the same figure (a
) is an explanatory diagram showing the state of a beam image at each actual distance. In the figure, 1 is a distance measuring module, 2 is a light emitting section, 3 is a light receiving section, 10 is a shielding member, and 11 is a screen. 12 is an infrared light emitter, 13 is a pivot, and 15 is a moving table. Patent Applicant Asahi Optical Industry Co., Ltd. Agent Patent Attorney No 1) Shigeru Figure 4 1゜ Figure 5 X^ Figure 6

Claims (1)

[Claims] A screen is placed directly in front of the ranging module under test at a predetermined distance, a spot beam image to be projected from a separate infrared emitter onto a plane at the actual distance is replaced on the screen, and this replaced image is placed on the screen. A distance measurement test method for an autofocus distance measurement module, characterized in that actual distance measurement is performed by focusing a spot beam image containing virtual distance information on a light receiving section of the distance measurement module.