JPH10253862A - Optical axis adjustment method and device therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical axis adjustment method and a device therefor, capable of easily and accurately adjusting an optical axis to the prescribed angle through the application of a simple structure. SOLUTION: A beam B1 is irradiated from a light source 1 to a half-mirror 10. As a result, the beam B1 is partly reflected as a beam B7 with the half- mirror 10, and partly transmitted as a beam B2. The beam B2 after the half- mirror 10 is reflected as a beam B3 with a total reflection mirror 11, while being reflected as a beam B4 with the half-mirror 10. The beam B2 is reflected as a beam B5 with a total reflection mirror 12 and transmitted through the half-mirror 10 as a beam B6. Then, the beam B6 is irradiated to a screen 20, together with the reflected beam B7, and the spot positions thereof are shown by a CCD camera 21. When the spot positions of the beams B6 and B7 separately appear, the beam B1 irradiated from the light source 1 is adjusted so that both of the beams 6 and 7 are irradiated in alignment with each other and form an interference fringe.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for adjusting an optical axis, and more particularly, to a method and an apparatus for adjusting the optical axis of a beam emitted from a light source to a predetermined direction or angle as a reference. It concerns the device.

[0002]

2. Description of the Related Art Laser beams are used in a wide variety of fields such as processing and measurement. An example of an apparatus that uses a laser beam for measurement includes a laser beam light source and a photomultiplier tube, which irradiates the laser beam from the light source and collides with the object to be measured. In some cases, the distance is measured by measuring the number of clock pulses received from a tube, for example, from irradiation to reception of a reflected laser beam. And such technology is used to measure the distance between vehicles and detect obstacles.In this case, a light source that irradiates while scanning an infrared laser beam that is invisible to the naked eye is mounted on the vehicle Is done.

In order to measure an inter-vehicle distance or detect an obstacle by scanning an infrared laser beam, it is necessary to adjust a reference optical axis to a predetermined angle (direction). As a conventional device for adjusting the optical axis of an infrared laser beam having a high directivity that cannot be seen by the naked eye, as shown in FIG. Some include a CCD camera 30 that captures an infrared laser beam b from the light source 1 and a CCD camera 32 that captures a spot position of the infrared laser beam b that is irradiated on the screen.

[0004] A CCD camera 30 for capturing the emission port is disposed at a position retracted from the optical axis of the infrared laser beam b emitted from the light source 1 toward the screen 31. Are disposed on the side opposite to the light source 1.

When the angle of the optical axis of the infrared laser beam b emitted from the light source is adjusted by using the above-described apparatus, the distance L from the exit of the light source 1 to the screen 31 is measured. In addition, as shown in FIG. 5, a target (intersection of the horizontal and vertical chain lines) M of the optical axis to be adjusted is set. Then, the position of the infrared laser beam b at the exit of the light source 1 and the infrared beam b irradiated on the screen 31
Are spotted by the CCD cameras 30 and 32, respectively, and the angle of the optical axis can be obtained from the coordinates of the two positions and the distance L. Further, the position of the infrared laser beam b at the exit of the light source 1 may be positioned at a predetermined position, and the target M shown in FIG. 5 may be adjusted so that the spot position S of the infrared beam b is irradiated. Furthermore, CCD
The target M can be corrected based on the position of the infrared laser beam b at the exit of the light source 1 captured by the camera 30, and the corrected target M can be adjusted so that the spot position S of the infrared beam b is irradiated.

[0006]

However, in the above-mentioned prior art, two CCD cameras 30 and 32 are required.
Since two CCD cameras are required, there is a problem that the cost is increased and the structure is complicated.

Further, since the CCD camera 30 for capturing the exit of the light source 1 is disposed at a position retracted from the optical axis of the infrared laser beam b irradiated from the light source 1 toward the screen 31, the CCD camera 30 is captured by the CCD camera 30. There is a problem that it is necessary to correct the position at the exit of the infrared laser beam b. This correction is not easy, the adjustment is complicated, and it is difficult to improve the optical axis adjustment accuracy.

Further, since the infrared laser beam b emitted from the light source 1 onto the screen 31 is captured by the opposed CCD camera 32, the position of the light source 1 in the height and width directions or the angle of the optical axis may vary depending on the height. There is a problem that the CCD camera 32 cannot catch the infrared beam b and the allowable range of the optical axis adjustment is narrow.

Furthermore, the position of the infrared laser beam b captured by the CCD camera 30 at the exit of the light source 1 is compared with the spot position S of the infrared beam irradiated on the screen 31 and captured by the CCD camera 32. Thus, in order to detect the angle of the optical axis and adjust the angle, it is necessary to increase the distance L between the exit of the light source 1 and the screen 31, and a large space for adjusting the optical axis is required. There was a problem of becoming.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to provide an optical axis adjusting method and apparatus which can easily and precisely adjust an optical axis to a predetermined angle with a simple structure. I do.

According to the first aspect of the present invention, in order to achieve the above object, a beam emitted from a light source is split into a plurality of beams, each split beam is irradiated toward an irradiation object, and each beam is irradiated on the irradiation object. The optical axis is adjusted on the basis of the irradiation state.

According to a second aspect of the present invention, there is provided an optical axis adjusting apparatus for adjusting an angle of an optical axis of a beam emitted from a light source, the optical axis adjusting apparatus having an optical system and an object to be irradiated. The optical system splits the beam emitted from the light source into a plurality of beams and emits the split beam toward an irradiation target, and the irradiation target expresses each of the irradiated beams in a distinguishable manner. Things.

According to a third aspect of the present invention, in order to achieve the above object, in the second aspect of the present invention, the beam for adjusting the optical axis is an infrared laser beam, and the irradiation target is a sensor capable of distinguishing the infrared laser beam. It is characterized by comprising.

According to the first aspect of the present invention, the beam emitted from the light source is split into a plurality of beams, and each split beam is irradiated toward an irradiation target. At this time, if the beams irradiated on the irradiation target do not match, the optical axis of the light source is adjusted so that the spot positions of the beams match.

In the invention according to claim 2, the beam emitted from the light source by the optical system is split into a plurality of beams, and the split beam is irradiated toward the irradiation target, and each of the irradiated beams is discriminated as the irradiation target. Make it possible. At this time, if the beams irradiated on the irradiation target do not match, the optical axis of the light source is adjusted so that the spot positions of the beams match.

According to a third aspect of the present invention, in the second aspect of the present invention, the infrared laser beam, which cannot be seen by the naked eye and is irradiated on the irradiation target, is determined by the sensor.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an optical axis adjusting method and apparatus according to the present invention will be described in detail with reference to FIGS. In this embodiment, the case where the optical axis of the infrared laser beam is adjusted to a predetermined reference angle as the beam emitted from the light source will be described. However, the present invention is not limited to this. Of course, the present invention can also be applied to the case where the optical axis of a beam, particularly the optical axis of a highly directional beam such as a laser beam is adjusted.

First, an optical axis adjusting device according to this embodiment will be described. As shown in FIG. 1, an optical axis adjustment device according to the present invention is an optical axis adjustment device for adjusting an angle of an optical axis of a beam emitted from a light source 1,
An optical system 2 and an irradiation target 3 are provided.
A plurality of beams B1 emitted from the laser beam are split into a plurality of beams, and the split beams are irradiated toward the irradiation target 3, and the irradiation target 3 represents each of the irradiated beams in a distinguishable manner.

The optical system 1 includes an anti-transmissive mirror (half mirror) 10 that reflects a part of the incident beam and transmits a part of the incident beam.
A reflecting mirror (referred to as a total reflecting mirror) 11, which totally reflects a part of the beam reflected by the half mirror 10,
12. The half mirror 10 has an anti-transmissivity on both surfaces thereof, and an infrared laser beam (hereinafter simply referred to as a beam) B emitted from the light source 1.
It is arranged so as to be inclined with respect to 1. Part of the beam B1 emitted from the light source 1 is transmitted through the half mirror 10 as a beam B2 traveling toward the total reflection mirror 11.
The total reflection mirror 11 converts the beam B2 transmitted through the half mirror 10 into a beam B3
As a total reflection. In the half mirror 10, the beam B3
Is reflected as a beam B4 toward the total reflection mirror 12. Further, the total reflection mirror 12 totally reflects the beam B4 again as a beam B5 directed to the half mirror 10. Furthermore, the half mirror 10 transmits the beam B5 as a beam B6 toward the irradiation target 3. On the other hand, a part of the beam B1 emitted from the light source 1 is reflected by the half mirror 10 as a beam B7 toward the irradiation target 3. As described above, the beam B1 emitted from the light source 1 is split into a plurality of beams B2 and B7, and finally the beam B6 is emitted toward the irradiation target 3 together with the beam B7.

In this embodiment, the irradiation target 3 is a screen 20 to which the beams B6 and B7 are finally irradiated.
And a half mirror 1 of the screen 20 as a sensor for indicating the spot positions of the infrared laser beams B6 and B7 applied to the screen 20 from the opposite surface.
0 and a CCD camera 21 arranged on the opposite surface.

Next, an optical axis adjusting method according to this embodiment will be described by using an optical axis adjusting device having the above-described configuration. The optical axis adjustment method according to the present invention,
In general, the beam B1 emitted from the light source 1 is split into a plurality of beams, and the split beams B6 and B7 are irradiated toward the irradiation target 3, and the beams B6 and B7 are irradiated on the irradiation target 3. The optical axis is adjusted based on the above.

The beam B1 is transmitted from the light source 1 to the half mirror 1
Irradiated towards zero. Since the half mirror 10 is disposed so as to be inclined with respect to the optical axis of the beam B1 emitted from the light source 1, the beam B1 is incident on the half mirror 10 and a part of the beam B1 is reflected and the screen B1 is reflected. The light is irradiated toward the mirror 10 and a part B2 is transmitted toward the total reflection mirror 11. The beam B2 transmitted toward the total reflection mirror 11 is totally reflected by the total reflection mirror 11 again as a beam B3 toward the half mirror 10. The half mirror 10 reflects the beam B3 as a beam B4 toward the total reflection mirror 12, and the total reflection mirror 12 totally reflects the beam B4 again as a beam B5 toward the half mirror 10. And half mirror 1
The beam B5 heading to 0 becomes a beam B6 transmitted through the half mirror 10, and together with the beam B7, the screen B2.
Go to zero.

Beams B6 and B7 applied to the screen
The spot position is displayed by a CCD camera 21 arranged on the opposite side of the screen 20.

FIGS. 2 and 3 show the states of the beams B6 and B7 irradiated on the screen 20 and detected by the CCD camera 21 as described above. FIG.
As shown in (2), when the spot positions of the split beams B6 and B7 are radiated separately into a plurality (two in this embodiment), it is determined that the optical axis is deviated from the predetermined angle. You. Further, as shown in FIG. 3, when the spot positions of the split beams B6 and B7 are radiated so as to coincide with each other and an interference fringe R is formed, it is determined that the optical axis is adjusted to a predetermined angle. Will be revealed. Therefore, FIG.
When the spot positions of the split beams B6 and B7 appear separately as shown in FIG. 3, the light source 1 is set so that the beams B6 and B7 coincide with each other to form an interference fringe R as shown in FIG. The angle of the optical axis of the beam B1 emitted from is adjusted.

As is clear from the above, the half mirror 10
The arrangement of the total reflection mirrors 11 and 12 is such that when the optical axis of the beam B1 from the light source 1 is adjusted to a desired angle, the beams B6 and B7 are irradiated onto the same spot position in accordance with the screen 20, and the interference fringes R Is set to form

In this embodiment, the configuration as described above allows one CC camera 30 and 31 to be used without the need for two CCD cameras 30 and 31 unlike the prior art.
Since the D camera 21 is sufficient, the configuration can be made inexpensive and simple.
It is not necessary to correct the position of the beam at the exit of the light source 1 captured by the light source, and the optical axis can be easily and accurately adjusted. Further, in this embodiment,
Instead of directly irradiating the beam B1 from the light source 1 onto the screen 20 as in the prior art, a half mirror 10 is used.
Even if the arrangement of the light source 1 is displaced in the height, width, front-back direction, etc., if the light is irradiated on the half mirror 10, the light can be irradiated on the screen 20, and the positioning accuracy of the light source 1 is affected. There is a wide allowable range in which the optical axis adjustment can be performed without any problem. Furthermore, with the simple configuration of the half mirror 10 and the total reflection mirrors 11 and 12, the beams B6 and B7 that are split and irradiated are greatly different depending on whether the optical axis needs to be adjusted or not. The optical axis can be easily and accurately adjusted in a short time. Moreover, with this configuration, it is not necessary to increase the distance L between the emission port of the light source 1 and the screen 31 unlike the prior art,
Therefore, a large space for adjusting the optical axis is not required.

In this embodiment, an infrared laser beam has been described as a beam for adjusting the optical axis. Therefore, a CCD camera for detecting the spot position of the infrared laser beam so as to be distinguishable is used. In the case of laser beams and other visible beams, no camera is needed, so that the split beam is coincident on the screen and illuminates the same spot position
What is necessary is just to adjust the direction of the optical axis of the beam emitted from the light source.

[0028]

According to the first aspect of the present invention, a beam emitted from a light source is split into a plurality of beams, each split beam is irradiated toward an irradiation target, and each beam is irradiated onto the irradiation target. Since the optical axis is adjusted based on the state, the optical axis can be adjusted to a predetermined angle easily and accurately with a simple structure.

According to the second aspect of the present invention, there is provided an optical axis adjusting device for adjusting an angle of an optical axis of a beam emitted from a light source, the optical axis adjusting apparatus having an optical system and an object to be irradiated. Has a simple structure by splitting the beam emitted from the light source into a plurality of beams and irradiating the split beam toward the irradiation target.The irradiation target is configured so that each irradiated beam can be distinguished from each other. An optical axis adjusting device capable of easily adjusting the optical axis to a predetermined angle with high accuracy can be provided.

According to the third aspect of the present invention, in the second aspect of the invention, when the beam for adjusting the optical axis is an infrared laser beam that cannot be seen by the naked eye, the irradiation target is identified as the infrared laser beam. By providing a possible sensor, each of the irradiated beams can be reliably determined.

[Brief description of the drawings]

FIG. 1 is a view schematically showing an optical axis adjusting device according to the present invention.

FIG. 2 is a diagram illustrating a state in which an infrared laser beam is emitted from a light source and is separated and emitted to a screen in a state where the optical axis of the infrared laser beam is shifted from a predetermined angle.

FIG. 3 is a diagram showing a state in which an optical axis of an infrared laser beam is emitted from a light source at a predetermined angle to be separated, and is irradiated on a screen to form an interference fringe.

FIG. 4 is a diagram schematically showing a conventional optical axis adjusting device.

FIG. 5 is a diagram showing a conventional target for adjusting an optical axis.

[Description of sign]

 DESCRIPTION OF SYMBOLS 1 Light source 2 Optical system 3 Irradiation target 21 CCD camera (sensor) B1-7 Infrared laser beam

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[Procedure amendment]

[Submission date] June 2, 1997

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claims

[Correction method] Change

[Correction contents]

[Claims]

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0012

[Correction method] Change

[Correction contents]

According to a second aspect of the present invention, there is provided an optical axis adjusting apparatus for adjusting an angle of an optical axis of a beam emitted from a light source, the optical axis adjusting apparatus having an optical system and an object to be irradiated. The optical system splits the beam emitted from the light source into a plurality of beams and irradiates the split beam toward an irradiation target, and the irradiation target indicates that the irradiation position of the irradiated beam can be detected.

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0015

[Correction method] Change

[Correction contents]

In the invention according to claim 2, the beam emitted from the light source by the optical system is split into a plurality of beams, and the split beam is irradiated toward the irradiation target, and the irradiation position (spot position) of the irradiated beam Appear detectably. At this time, if the beams irradiated on the irradiation target do not match, the optical axis of the light source is adjusted so that the spot positions of the beams match.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0018

[Correction method] Change

[Correction contents]

First, an optical axis adjusting device according to this embodiment will be described. As shown in FIG. 1, an optical axis adjustment device according to the present invention is an optical axis adjustment device for adjusting an angle of an optical axis of a beam emitted from a light source 1,
An optical system 2 and an irradiation target 3 are provided.
Irradiates the beam B1 illuminated from a plurality of beams and irradiates the split beam toward the irradiation target 3, and the irradiation target 3 indicates a spot irradiation position of the irradiated beam in a detectable manner.

[Procedure amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0020

[Correction method] Change

[Correction contents]

In this embodiment, the irradiation target 3 is a screen 20 to which the beams B6 and B7 are finally irradiated.
And a half mirror 1 of the screen 20 as a sensor for detecting the spot positions of the infrared laser beams B6 and B7 applied to the screen 20 from the opposite surface.
0 and a CCD camera 21 arranged on the opposite surface.

[Procedure amendment 6]

[Document name to be amended] Statement

[Correction target item name] 0029

[Correction method] Change

[Correction contents]

According to the second aspect of the present invention, there is provided an optical axis adjusting device for adjusting an angle of an optical axis of a beam emitted from a light source, the optical axis adjusting apparatus having an optical system and an object to be irradiated. Has a simple structure by splitting the beam emitted from the light source into a plurality of beams and irradiating the split beam toward the irradiation target, and the irradiation target is configured to be able to detect the irradiation position of the irradiated beam. Thus, it is possible to provide an optical axis adjusting device that can easily adjust the optical axis to a predetermined angle with high accuracy.

Claims (3)

[Claims] 1. A beam emitted from a light source is split into a plurality of beams, each split beam is irradiated toward an irradiation target, and an optical axis is adjusted based on a state in which each beam irradiates the irradiation target. An optical axis adjustment method, characterized in that: 2. An optical axis adjusting device for adjusting an angle of an optical axis of a beam emitted from a light source, comprising: an optical system and an irradiation target, wherein the optical system converts the beam emitted from the light source. An optical axis adjusting device, comprising: splitting a plurality of beams and irradiating the split beam toward an irradiation target, and the irradiation target expresses each of the irradiated beams in a distinguishable manner. 3. The optical axis adjusting device according to claim 1, wherein the beam for adjusting the optical axis is an infrared laser beam, and the irradiation target includes a sensor capable of distinguishing the infrared laser beam.