JPH04240506A - Optical regulator of measuring device of dimension and using method thereof - Google Patents

Abstract

PURPOSE:To make it possible to conduct simply an operation of position alignment of the optical axis of a projected light beam emitted from a light projecting part with the center of a slit of a light sensing part in a transmission type device for measuring dimensions. CONSTITUTION:An optical regulator 4 is fitted to a light sensing part 2, and two openings 5a and 5b having equal opening areas are disposed to be symmetric linearly in respect to a line C passing through the center of a slit 3 and being perpendicular to the direction of the length of the slit 3. Next, a projected light beam beta is oscillated vertically, the openings 5a and 5b are closed one by one alternately and thereby regulation is made so that an output of the light sensing part be equal. Moreover, the projected light beam beta is oscillated laterally and regulation is made so that the output of the light sensing part be maximum.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical adjuster used for optically aligning a light emitting section and a light receiving section of a transmission type dimension measuring device, and a method of using the optical adjuster.

0002

2. Description of the Related Art FIG. 4 shows an external view of a transmission type dimension measuring device. The dimension measuring device consists of a light emitting part 1 and a light receiving part 2,
are placed opposite each other. Inside the light projection unit 1, there are a light emitting source (not shown) such as a semiconductor laser, a light emitting diode (LED), or a lamp, and a lens (not shown) for converting the light emitted from the light source into parallel light. Built-in. In addition, a slit 3 is opened in the front surface of the light receiving section 2, and a photodiode (PD) and a PD for receiving the light incident through the slit 3 and detecting the amount of light received are installed inside.
A light receiving element (not shown) such as an array or a charge-coupled device (CCD) is built in, and the center of the light receiving element and the center of the slit 3 are aligned.

[0003]In this dimension measuring device, the projecting beam emitted from the projecting section 1 is irradiated onto the object, and the receiving section 2 detects the state of light shielding by the opaque object or the amount of light transmitted through the translucent object. to measure the dimensions of an object.

In the transmission type dimension measuring device as described above, the light projecting section 1 and the light receiving section 2 are arranged in advance so that the projection beam emitted from the light projecting section 1 is irradiated onto the entire slit 3 of the light receiving section 2. It is necessary to adjust the positional relationship. In particular, in this adjustment work, it is desirable to align the optical axis α of the projected beam with the center of the slit 3.

For this reason, conventionally, the light emitter 1 and the light receiver 2 are arranged facing each other, and the light emitter 1 is moved while monitoring the output signal of the light receiver 2 to direct the emitted light beam vertically and horizontally. The adjustment was completed when the output value from the light receiving section 2 reached the maximum, and the light projecting section 1 and the light receiving section 2 were fixed.

[0006]

[Problem to be Solved by the Invention] However, in the above method of aligning the optical axis of the light emitting beam and the center of the slit, the output value of the light receiving part is maximized by moving the light emitter up, down, left and right. It took a long time to determine the state that would result, and the adjustment work was time-consuming. In addition, with such an adjustment method, even if the output value of the light receiving section is set to be the maximum, it is not clear whether the optical axis of the projected beam and the center of the slit are in the desired state of alignment.

The present invention has been made in view of the drawbacks of the conventional examples described above, and its purpose is to align the optical axis of the projected beam of a transmission type dimension measuring device with the center of the slit. An object of the present invention is to provide an optical adjuster and a method for using the same to facilitate the use of the optical adjuster.

[0008]

[Means for Solving the Problems] The optical adjuster of the dimension measuring device of the present invention irradiates the object with a projection beam from the projection section,
The optical axis of the emitted beam and the center of the slit are used in a device that measures the dimensions of an object by making the emitted light beam enter a slit in the light receiving part and detecting the amount of received light that changes when it is blocked by the object. The optical adjuster includes a mask part that blocks the projected light beam emitted from the light projecting part, two openings formed in the mask part, and these two openings are arranged to match the light receiving part. It is characterized by comprising means for positioning the mask part on the light receiving part so that the mask part coincides with the slit, and the positions of both openings are axisymmetric with respect to a line in the slit width direction passing through the center of the slit.

A method of using an optical adjuster according to the present invention is a method of using an optical adjuster for aligning the optical axis of a projected beam emitted from a light projecting section with the center of a slit opened in a light receiving section. A mask section is attached to the light receiving section, and the two openings of the mask section are aligned with the slit, and both openings are arranged so as to be symmetrical with respect to a line in the slit width direction passing through the center of the slit. Move the emitter or light receiver so that the output of the light receiver when only one aperture is blocked is equal to the output of the light receiver when only the other aperture is blocked, and compare the output of the light receiver when only one aperture is blocked. The feature is that the light emitter or light receiver is moved while maintaining the same state with the light receiver output when only the other opening is closed, and the positions of the light emitter and light receiver are adjusted so that the light receiver output is maximized. It is said that

0010

[Function] Since both openings of the mask attached to the light receiving section are arranged symmetrically with respect to the line in the slit width direction passing through the center of the slit, the output of the light receiving section when only one opening is closed is If the output of the light receiving section is made equal when only the other opening is closed, the optical axis of the projected light beam will coincide with a line passing through the center of the slit in the slit width direction. Furthermore, the output of the light receiving part is maximized by moving the light emitter or the light receiving part while keeping the output of the light receiving part when only one aperture is closed and the output of the light receiving part when only the other aperture is closed. If this is done, the optical axis of the projected beam will coincide with the center of the slit.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples of the present invention will now be described in detail with reference to the accompanying drawings. FIG. 1 shows an optical adjuster 4 and a light receiving section 2 according to an embodiment of the present invention. The light receiving section 2 has a prismatic outer shape, and a slit 3 for receiving light is opened in the front surface. Optical adjuster 4
has a square box shape, and an outer edge portion 6b for positioning is formed on the outer periphery of the mask portion 6a. That is, the inner peripheral dimension of this outer edge part 6b is formed to be equal to the outer peripheral dimension of the light receiving part 2, and when the optical adjuster 4 is attached so as to cover the front part of the light receiving part 2, the optical adjuster 4 will be attached to the outer peripheral dimension. Part 6
b is positioned on the light receiving section 2. The mask portion 6a of the optical adjuster 4 is provided with two circular openings 5a and 5b having the same opening area, and as shown in FIG. 1, the optical adjuster 4 is attached to the light receiving portion 2. When positioned, the two openings 5a and 5b overlap the slit 3, and a line C passing through the center of the slit 3 and perpendicular to the length direction of the slit 3 (this is a hypothetical line, but actually There is no need for a line to be drawn.

A method of adjusting the positions of the light projecting section 1 and the light receiving section 2 of the transmission type dimension measuring apparatus using the optical adjuster 4 will be explained. First, as shown in FIG. 1, the optical adjuster 4 is securely attached to the front surface of the light receiving section 2 by aligning the slit 3 with the two openings 5a and 5b. 2 (
As shown in a), the light beam β is transmitted from the light projector 1 to the optical adjuster 4.
irradiate.

Next, the optical axis α of the projected beam β is positioned in the length direction of the slit 3 in the following manner. first,
Only one opening 5a is closed with a finger, and the other opening 5b is closed.
Monitor the output of the light receiving section 2 while being careful not to block the light, and similarly monitor the output of the light receiving section 2 by covering only the other opening 5b with your finger, and then shake the light projecting section 1 up and down to emit light. The light beam β is moved up and down and adjusted so that the outputs of the light receiving section become equal when the apertures 5a and 5b are alternately opened and closed. When this adjustment is completed, the optical axis α of the projected beam β will be
As shown in (b), it is located on a line C passing through the center of the slit 3 and perpendicular to the length direction of the slit 3.

After the adjustment of the slit 3 in the length direction is completed, the adjustment of the slit 3 in the width direction is performed. In other words, by swinging the light projecting unit 1 left and right, the projecting beam β is moved left and right,
Adjust so that the output of the light receiving section 2 becomes maximum. When this adjustment is completed, the optical axis α of the projected beam β is located at the center of the two apertures 5a and 5b, that is, at the center of the slit 3, as shown in FIG. 2(c).

As described above, according to the method of the present invention, adjustment can be made sequentially in the length direction and the width direction of the slit 3 while monitoring the output of the light receiving section, thereby facilitating the adjustment work. Furthermore, in the length direction of the slit 3, it is possible to use an adjustment method of equalizing the light receiving section outputs, which is simpler and more reliable than finding the maximum value of the light receiving section outputs.

FIG. 3 shows an optical adjuster 1 according to another embodiment of the present invention.
FIG. This is done by attaching the base of a rice scoop-shaped movable shielding plate 7 to the optical adjuster 10 via a pivot 8, and by rotating the movable shielding plate 7, a shielding portion 9 at the tip of the movable shielding plate 7 can open either the opening 5a or 5b. It was made so that it could be blocked. By using this optical adjuster 10, there is no need to block the openings 5a and 5b with fingers or the like during adjustment work, and the two openings 5a and 5b can be opened and closed alternately with the movable shielding plate 7, making it easy to make fine adjustments. Ru.

[0017]

Effects of the Invention According to the present invention, when both apertures are alternately closed, the light emitting part or the light receiving part is moved so that the output of the light receiving part is equalized, so that the light emitting beam is aligned on a line passing through the center of the slit. This makes the adjustment work easier and more reliable than the method of finding the maximum value of the output of the light receiving section. Furthermore, since the maximum value of the output of the light receiving section is found only in the width direction of the slit, the adjustment work is easier than in the conventional method of finding the maximum value in two directions at the same time. That is, according to the present invention, the projection beam and the slit center can be aligned sequentially in each direction, and in one direction, it is only necessary to select a position where the output of the light receiving section is equal, and the optical axis of the projection beam can be aligned. The position adjustment between the slit center and the slit center can be performed extremely efficiently and reliably.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing an optical adjuster and a light receiving section according to an embodiment of the present invention.

2(a), (b), and (c) are perspective views for explaining how to use the optical adjuster of FIG. 1. FIG.

FIG. 3 is a perspective view showing an optical adjuster according to another embodiment of the present invention.

FIG. 4 is a perspective view showing a transmission type dimension measuring device.

[Explanation of symbols]

1 Light projecting section 2 Light receiving part 3 Slit 4,10 Optical adjuster 5a, 5b Opening 6a Mask part 6b Outer edge

Claims (2)

[Claims] 1. A light projecting section emits a light projection beam onto an object, the projecting beam enters a slit in a light receiving section, and the light receiving section detects the amount of received light that changes as the projecting beam is blocked by the object, An optical adjuster for aligning the optical axis of a projected beam with the center of a slit in an apparatus for measuring the dimensions of an object, the optical adjuster comprising: a mask section for blocking the projected beam emitted from the light projecting section; two openings formed in the section, so that these two openings coincide with the slit of the light receiving section, and so that the positions of both openings are symmetrical with respect to a line in the slit width direction passing through the center of the slit, An optical adjuster for a dimension measuring device comprising a means for positioning a mask part to a light receiving part. 2. A method of using an optical adjuster for aligning the optical axis of a projected beam emitted from a light projecting section with the center of a slit opened in a light receiving section, the method comprising: attaching a mask section to the light receiving section; Output from the light receiving section when installed, aligning the two openings of the mask section with the slit, arranging both openings so that they are symmetrical with respect to the line in the slit width direction passing through the center of the slit, and blocking only one opening. Move the emitter or light receiver so that the output of the light receiver when only the other aperture is closed is equal to the output of the light receiver when only the other aperture is closed, and the output of the light receiver when only the other aperture is closed. A method of using an optical adjuster in which the light emitter or the light receiver is moved while the output of the light receiver remains equal, and the positions of the light emitter and the light receiver are adjusted so that the output of the light receiver is maximized.