JP3385218B2 - Laser beam optical axis deviation detector - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser beam optical axis deviation detecting device, and more specifically, it accurately detects an optical axis deviation of a laser beam without causing a time lag between the time of optical axis deviation and the time of detection. The present invention relates to a laser beam optical axis deviation detecting device which can be continuously used as well as the detecting device.

[0002]

2. Description of the Related Art In a laser processing apparatus, a laser beam emitted from a laser oscillator is guided to a condenser lens of a processing head via a plurality of reflecting mirrors. The laser beam is condensed on the work by the condenser lens, and the heat melts the work. By the way, if the angle of the reflecting mirror is deviated due to some cause, for example, a shock such as movement or an earthquake, the optical axis of the laser beam is deviated. If the optical axis of the laser beam is deviated, the beam will be scattered in the wrong direction, resulting in defective machining.

In order to solve this problem, conventionally, a thin metal wire is arranged around the optical axis of the laser beam to detect the deviation of the transmission optical path of the laser beam. Figure 10
The reference diagram is shown in FIG. In this laser beam optical axis shift detection device 500, when the optical axis of the laser beam L shifts, the metal thin wire 501 disposed around the laser beam optical axis is irradiated with the laser beam L, and the metal thin wire 501 melts. Since the electrical connection is cut off by cutting the thin metal wire 501, this is detected, and the laser control device 502 stops the oscillation of the laser oscillator 503.

FIG. 11 is a block diagram of another conventional laser beam optical axis shift detecting device. This laser beam optical axis shift detection device 600 has a configuration in which a plurality of temperature sensors 601 are evenly arranged around the laser beam L. When the optical axis of the laser beam L shifts, the laser beam L approaches any one of the temperature sensors 601, so that the temperature of each temperature sensor 601 varies. Temperature sensor 601
Is sent to the laser control device 602, and the deviation of the optical axis of the laser beam is judged from the degree of variation in each signal value.
Based on this determination result, the laser control device 602 stops the oscillation of the laser oscillator 603.

[0005]

However, the conventional laser beam optical axis deviation detecting device 500 cannot detect the deviation of the laser beam optical axis until the thin metal wire 501 is melted. There was a problem that there was a time lag between. Also, the laser beam L
When the output is low, the metal thin wire 501 cannot be melted and the optical axis shift of the laser beam L cannot be detected. Further, since it is necessary to replace the melted metal thin wire 501, there is a problem that it cannot be used continuously.

Next, in the conventional laser beam optical axis deviation detecting device 600, since the temperature sensor 601 is used, there is a problem that there is a possibility of erroneous detection due to the influence of the ambient temperature. Further, when the temperature sensor 601 is directly irradiated with the strong laser beam L, the temperature sensor 601 is damaged and cannot be used continuously.
Further, when the temperature sensor 601 is covered with a metal tube (not shown) in order to prevent the temperature sensor 601 from being damaged, the heat of the laser beam L is transferred to the temperature sensor 6 through the metal tube.
Therefore, there is a problem that there is a time lag between the time of optical axis shift and the time of detection.

The present invention has been made in view of the above, and there is no time lag between the optical axis shift and the detection time, the optical axis shift of the laser beam can be accurately detected, and the detection device is provided. It is an object of the present invention to obtain a laser beam optical axis shift detection device that satisfies the condition that it can be continuously used.

[0008]

In order to achieve the above object, a laser beam optical axis deviation detecting device according to the present invention includes a laser beam blocking member having a laser beam passage hole through which a laser beam passes, and a laser beam blocking member. It has a small-diameter laser beam passage hole with a diameter smaller than that of the member's laser-beam passage hole and the center axis is the same, and the laser beam is cut off by a reflector plate with a tapered portion at the periphery of this small-diameter laser beam passage hole And an infrared sensor provided at a position where reflected light from the reflection plate can be incident.

The laser beam optical axis deviation detecting device is arranged so that the optical axis of the laser beam is located at the center of the small diameter laser beam passage hole. When the optical axis of the laser beam deviates, the laser beam interferes with the peripheral edge of the reflection plate and is reflected. This reflected laser beam is captured by an infrared sensor. Thereby, the optical axis shift of the laser beam can be detected. Further, since the laser beam is not directly incident on the infrared sensor by the laser beam blocking member, the infrared sensor can be prevented from being damaged. Further, since the laser beam passage hole of the laser beam blocking member is larger than the small diameter laser beam passage hole of the reflection plate, the reflected light from the work side is blocked by the reflection plate. Therefore, malfunction of the infrared sensor can be prevented.

A laser beam optical axis deviation detecting device according to the next invention comprises a base block having a laser beam passage hole through which a laser beam passes, and a hole portion provided on an inner wall surface of the laser beam passage hole of the base block. An infrared sensor fitted into the hole until the end sinks from the wall surface, and a small-diameter laser beam passage hole with a smaller diameter than the laser beam passage hole of the base block and having the same central axis as well as provided on the work side of the base block. A reflecting plate having a tapered portion on the periphery of the small-diameter laser beam passage hole.

The position of the laser beam optical axis deviation detecting device is fixed so that the optical axis of the laser beam passes through the center of the laser beam passage hole of the base block. When the optical axis of the laser beam is not displaced, the laser beam passes through substantially the center of the laser beam passage hole of the base block and the small diameter laser beam passage hole of the reflector. When the optical axis of the laser beam is deviated, first, the small-diameter laser beam passage hole interferes with the laser beam. At the periphery of the small-diameter laser beam passage hole,
Since the tapered portion is provided, the laser beam is mainly reflected at this portion toward the inner wall surface of the laser beam passage hole.
The laser beam reflected toward the inner wall surface is detected by the infrared sensor fitted to the inner wall surface.

Further, since the infrared sensor is fitted into the inner wall surface of the laser beam passage hole so that its end portion is sunk, the laser beam does not hit directly. Therefore, damage to the infrared sensor can be prevented. Further, since the small-diameter laser beam passage hole is located on the work side of the laser beam passage hole, light reflected on the work surface or light emitted during processing is blocked by the reflector. Therefore, malfunction can be prevented.

According to another aspect of the invention, there is provided a laser beam optical axis shift detecting device, wherein an annular reflecting plate for reflecting the laser beam is provided, and the reflecting plate is annular and its central axis is substantially aligned with the central axis of the annular ring of the reflecting plate. A laser beam blocking member having a ring inner diameter larger than the ring inner diameter of the reflection plate, and an infrared sensor provided on the reflection plate side of the laser beam blocking member and facing the reflection plate. It is a thing.

The laser beam optical axis shift detecting device is arranged so that the optical axis of the laser beam is located at the center of the ring of the reflector. When the optical axis of the laser beam deviates, the laser beam interferes with the peripheral edge of the reflection plate and is reflected. Since the infrared sensor is provided so as to face the reflecting plate, the reflected laser beam can be captured by this infrared sensor. Thereby, the optical axis shift of the laser beam can be detected.

Further, since the infrared sensor is located on the back side of the laser beam blocking member when viewed from the incident direction of the laser beam, the infrared sensor is not directly irradiated with the laser beam. Therefore, damage to the infrared sensor can be prevented. Further, since the inner diameter of the ring of the laser beam blocking member is larger than the inner diameter of the ring of the reflecting plate and the infrared sensor is arranged along this laser beam blocking member, the reflected light from the work side is blocked by the reflecting plate. Therefore, it is difficult for the reflected light from the work to reach the infrared sensor, so that malfunction can be prevented.

A laser beam optical axis shift detecting device according to the next invention is the above laser beam optical axis shift detecting device, further comprising fine irregularities provided on the surface of the reflecting plate.

By providing fine irregularities on the surface of the reflection plate, it is possible to diffusely reflect the laser beam. Diffuse reflection allows more laser beams to be incident on the infrared sensor. Therefore, the deviation of the optical axis of the laser beam can be detected more accurately.

A laser beam optical axis shift detecting device according to the next invention is the above laser beam optical axis shift detecting device, further comprising a filter for transmitting only the laser beam on the surface of the infrared sensor.

When an infrared sensor is used, malfunction may occur due to ambient natural light or light emission when cutting a workpiece, but the malfunction can be further prevented by providing a filter on the surface of the infrared sensor.

In the laser beam optical axis shift detecting device according to the next invention, in addition to the above laser beam optical axis shift detecting device, an infrared sensor detects that the optical axis of the laser beam is shifted, and a detection signal of this infrared sensor is detected. Based on the above, a predetermined coping operation is performed.

When the optical axis shift of the laser beam is detected,
For example, processing operations such as issuing an alarm and stopping the laser oscillator are performed. As a result, continuous irradiation of the laser beam whose optical axis is shifted can be stopped, so that damage to parts and the like can be prevented.

A laser beam optical axis shift detecting device according to the next invention is the above laser beam optical axis shift detecting device, wherein the laser beam input resistance performance of the infrared sensor is further set as a threshold value of the processing operation. .

If the above-mentioned processing operation, for example, the laser oscillator is stopped when the input resistance performance of the laser beam is exceeded, damage to the infrared sensor can be prevented in advance. As a result, the maintenance work of the laser beam optical axis shift detection device can be reduced.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A laser beam optical axis shift detecting device according to the present invention will be described in detail below with reference to the drawings. The present invention is not limited to this embodiment.

Embodiment 1. 1 is a front view showing a laser beam optical axis shift detecting device according to a first embodiment of the present invention. FIG. 2 is a sectional view of the laser beam optical axis shift detecting device shown in FIG. In this laser beam optical axis deviation detecting device 100, a circular laser beam passage hole 2 is provided at the center of a base block 1 (laser beam blocking member). Four hole portions 4 are evenly formed on the wall surface 3 of the laser beam passage hole 2.

An infrared sensor 5 is provided in each of the holes 4.
It is inset. The end 51 of the infrared sensor 5 is set in the hole 4 and is sunk from the wall surface 3. This is done so that the infrared sensor 5 does not directly receive the incident laser beam. Therefore, even when a strong laser beam is incident, only the reflected light reaches the infrared sensor 5, so that the infrared sensor 5 can be prevented from being damaged.

A reflecting plate 6 is provided on one surface of the base block 1. The reflection plate 6 is provided with a laser beam passage hole 7 through which the laser beam passes. The diameter of the laser beam passage hole 7 is set to be slightly larger than the laser beam optical axis diameter. The diameter of the laser beam passage hole 7 provided in the reflection plate 6 is smaller than the diameter of the laser beam passage hole 2 provided in the base block 1. Although the laser beam is reflected on the surface of the work (not shown), the light reflected from the work can be blocked by reducing the diameter of the laser beam passage hole 7 of the reflection plate 6. Therefore, erroneous detection due to the reflected light from the work can be prevented.

The periphery of the laser beam passage hole 7 of the reflection plate 6 is tapered (tapered portion 8). A material having a high reflectance is selected as the material of the reflection plate 6. For example, in the case of a carbon dioxide laser device, it is preferable to use aluminum or copper in terms of function and cost. Also,
The reflecting surface 61 of the reflecting plate 6 is provided with fine irregularities. This is because the laser beam is diffusely reflected by the reflecting surface 61 and the laser beam is surely incident on the infrared sensor 5.

A filter that allows only the laser beam to pass may be attached to the surface of the infrared sensor 5 (not shown). For example, carbon dioxide laser device (wavelength 1
In the case of 0.6 μm, it is used for a filter made of silicon (Si), germanium (Ge), quartz (KRS5) or the like. As a result, the effects of natural light, visible light such as illumination, and reflected light when cutting the work can be minimized.

FIG. 3 shows a laser beam optical axis deviation detecting device 1.
It is a circuit diagram which shows 00. A sensor amplifier 9 is connected to the infrared sensor 5. Further, since the infrared sensor 5 has a temperature characteristic, temperature compensation is necessary. For this reason,
A temperature compensation sensor 10 is provided in this circuit. A temperature compensation sensor amplifier 11 is connected to the temperature compensation sensor 10. The signals from the infrared sensor 5 and the temperature compensation sensor 10 are input to the summing amplifier 12. Summing amplifier 12
A comparator 14 with the reference voltage 13 is connected to the. The comparator 14 is connected to the laser control device 15. The laser control device 15 controls an alarm and on / off of a laser oscillator.

FIG. 4 is an explanatory view showing an installation example of the laser beam optical axis shift detecting device 100. Usually, the optical system of the laser processing equipment includes a laser oscillator 201 for emitting a laser beam L, a reflection mirror 202 through the upper predetermined path by reflecting the laser beam L, current focusing the laser beam L on the workpiece W It is composed of an optical lens 203 and a processing head 204 that holds the condenser lens 203. The optical axis shift of the laser beam L is caused by the internal state of the laser oscillator 201 and the angular error of the reflecting mirror 202.

For this reason, the laser beam optical axis deviation detecting apparatus 100 is arranged in the subsequent stage of the reflecting mirror 202, that is, the processing head 2.
0 4 preferably placed in front (in the drawing position A). In order to identify the cause of the optical axis deviation, the laser beam optical axis deviation is detected between the laser oscillator 201 and the reflecting mirror 202 (position B in the drawing) and in front of the processing head 204 (position A in the drawing). The device 100 may be installed. The above position
It can be installed on other than .

Next, the operation of the laser beam optical axis deviation detecting device 100 will be described. FIG. 5 is an explanatory diagram showing a case where the optical axis of the laser beam L is in the normal position.
FIG. 6 is an explanatory diagram showing a case where the optical axis of the laser beam L is displaced. The laser beam optical axis shift detection device 100 is installed so that the laser beam L passes through the center of the laser beam passage hole 7 of the reflection plate 6.

Since the diameter D of the laser beam passage hole 7 is set to be slightly larger than the diameter d of the laser beam L, when the optical axis of the laser beam is not displaced, the reflection plate 6 and the laser beam L are not moved. And do not interfere. Therefore, the laser beam L does not enter the infrared sensor 5.

When the optical axis of the laser beam L is deviated, the laser beam L interferes with the laser beam passage hole 7 (reflection plate 6). Since the periphery of the laser beam passage hole 7 is a tapered portion 8, the laser beam L is formed at this portion.
Reflects in the direction of the wall surface 3 and scatters due to the fine unevenness of the reflecting surface 61. This reflected and scattered laser beam L '
Enters the infrared sensor 5 provided on the wall surface 3. Since the infrared sensor 5 outputs a voltage determined according to the amount of incident light, the optical axis shift of the laser beam L can be detected by the change in the amount of incident light.

Next, the processing of the signal output from the infrared sensor 5 will be described. Since the output signal of the infrared sensor 5 has an extremely low voltage, it is amplified by the sensor amplifier 9. The amplified signal is input to one terminal of the summing amplifier 12. Further, the output signal of the temperature compensation sensor 10 is amplified by the temperature compensation sensor amplifier 11, and the summing amplifier 1
2 is input to the other terminal.

In the adding amplifier 12, the output signal of the infrared sensor 5 and the output signal of the temperature compensation sensor 10 are added and amplified. The output signal thus added and amplified is input to one terminal of the comparator 14. On the other hand, the reference voltage is input to the other terminal of the comparator 14. This reference voltage serves as a threshold value for operating the comparator 14. The threshold value is set in advance from the optical axis deviation allowable amount of the laser beam L.

When the infrared sensor 5 receives the laser beam L above the reference voltage, the comparator 14 outputs a signal voltage. On the contrary, if the voltage is equal to or lower than the reference voltage, the signal voltage is not output from the comparator 14. The signal voltage of the comparator 14 is input to the laser control device 15. The laser control device 15 performs processing such as issuing a warning to the user and stopping the laser oscillator 201.

Further, the reference voltage may be set to be equal to or lower than the laser beam input resistance performance of the infrared sensor 5.
With this configuration, even when the laser beam L having the withstand input capability or higher is incident on the infrared sensor 5, the laser oscillator 20
1 can be stopped. Therefore, even if the laser beam optical axis shift occurs, the infrared sensor 5 is not destroyed.

As the signal processing of the infrared sensor 5, in addition to the above circuit, the voltage of the infrared sensor 5 may be quantitatively measured using an AD converter or the like, and depending on the irradiation degree of the laser beam L, The alarm and the stop of the laser oscillator 201 may be performed in stages.

As described above, according to the laser beam optical axis shift detecting apparatus 100 of the present invention, since the reflected light is directly incident on the infrared sensor 5, there is no time lag between the optical axis shift and the detection time. Further, since the laser beam passage hole 7 of the reflection plate 6 has a small diameter, noise is less likely to enter. Therefore, the optical axis shift of the laser beam L can be accurately detected. further,
Since the infrared sensor 5 can be prevented from being damaged, the device can be continuously used.

Embodiment 2. FIG. 7 is a front view showing a laser beam optical axis shift detecting device according to the second embodiment of the present invention. FIG. 8 is a sectional view showing the laser beam optical axis shift detection device shown in FIG. In this laser beam optical axis shift detection device 300, the laser beam blocking member 3
01 has a ring shape having a circular laser beam passage hole 302.

On the back surface of the laser beam blocking member 301,
Four infrared sensors 303 are evenly arranged along the circumference of the laser beam passage hole 302. Infrared sensor 3
03 is provided on the back side of the laser beam blocking member 301 in order to prevent the laser beam L from directly irradiating the infrared sensor. Therefore, even when the strong laser beam L is incident, it is blocked by the laser beam blocking member 301, so that the infrared sensor 303 can be prevented from being damaged.

[0044] The reflection plate 304 so as to face the laser beam blocking member 30 1 is installed. The laser beam blocking member 301 and the reflection plate 304 are connected via a square tube 305. This is to prevent the incidence of extra light by closing the periphery with the square tube 305. Further, the reflector 304 has a ring shape having a laser beam passage hole 306 through which the laser beam L passes. The diameter D of the laser beam passage hole 306 is set to be slightly larger than the laser beam optical axis diameter d.

Further, the diameter of the laser beam passage hole 306 provided in the reflection plate 304 is determined by the laser beam blocking member 301.
The diameter is smaller than the diameter of the laser beam passage hole 302 provided in. By making the diameter of the laser beam passage hole 306 of the reflecting plate 304 small, it is possible to block the reflected light from the work (not shown). Therefore, erroneous detection due to the reflected light from the work can be prevented.

Further, a taper portion 307 is provided on the periphery of the laser beam passage hole 306 of the reflecting plate 304. The angle of the taper portion 307 is set so that the laser beam L whose optical axis is deviated is exactly incident on the infrared sensor 303 when reflected. A material having a high reflectance is selected as the material of the reflector 304 (see Embodiment 1 for a specific example). Further, similar to the first embodiment, the reflection surface of the reflection plate 304 is provided with fine irregularities (not shown), or a filter (not shown) for passing only the laser beam L is attached to the surface of the infrared sensor 303. May be.

This laser beam optical axis deviation detecting device 300
Is preferably installed immediately before the processing head of the laser processing apparatus, as in the first embodiment (see FIG. 4). The laser beam optical axis shift detection device 300 is installed so that the laser beam L passes through the center of the laser beam passage hole 306 of the reflection plate 304. Also, the laser beam passage hole 306
Is set to be slightly larger than the diameter d of the laser beam L, so that the reflection plate 304 and the laser beam L do not interfere as shown in FIG. 8 when the optical axis of the laser beam is not displaced. Therefore, the laser beam L does not enter the infrared sensor 303.

FIG. 9 is an explanatory view showing a case where the optical axis of the laser beam is deviated. When the optical axis of the laser beam L is deviated, the laser beam L passes through the laser beam passage hole 306.
Interference with (reflector 304) occurs. Since the tapered portion 307 is provided on the periphery of the laser beam passage hole 306, the laser beam L is reflected at this portion and is scattered by the fine irregularities on the surface of the reflector. The reflected and scattered laser beam L ′ is incident on the infrared sensor 303 provided on the back surface of the laser beam blocking member 301. Infrared sensor 30
Since 3 outputs a voltage determined according to the amount of incident light,
The shift of the optical axis of the laser beam L can be detected by the change in the amount of incident light.

The signal output from the infrared sensor 303 is
Since it is processed by the same circuit as that of the first embodiment, description thereof will be omitted.

As described above, the laser beam optical axis shift detecting device 300 of the present invention has a simple structure and therefore does not cost the device. Further, as in the first embodiment, since the reflected light is directly incident on the infrared sensor 303, there is no time lag between the time of optical axis shift and the time of detection. Further, since the laser beam passage hole 306 of the reflecting plate 304 has a small diameter, noise is less likely to enter, and the optical axis shift of the laser beam L can be accurately detected. Further, since the infrared sensor 303 can be prevented from being damaged, the device can be continuously used.

[0051]

As described above, according to the laser beam optical axis shift detecting device of the present invention, the reflected light can be directly incident on the infrared sensor, so that the optical axis shift is detected and the optical axis shift is detected. There is no time lag. Further, since the malfunction of the infrared sensor can be prevented, the deviation of the optical axis of the laser beam can be accurately detected. Further, since the infrared sensor can be prevented from being damaged, the device can be continuously used.

In the laser beam optical axis deviation detecting device of the next invention, the laser beam reflected by the taper portion of the peripheral edge of the small diameter laser beam passage hole is directly incident on the infrared sensor fitted to the inner wall surface of the base block. Therefore, there is no time lag between the time when the optical axis is displaced and the time when the optical axis is detected.

Further, since the infrared sensor is fitted into the inner wall surface of the laser beam passage hole so that the end thereof is sunk so that the incident laser beam does not directly hit the infrared sensor, damage to the infrared sensor can be prevented. Therefore, the optical axis shift of the laser beam can be accurately detected. Since the light reflected on the work surface and the light emitted during processing are blocked by the reflector, malfunctions can be prevented. Therefore, the device can be used continuously.

According to the laser beam optical axis deviation detecting device of the next invention, since the infrared sensor is provided so as to face the reflecting plate, the reflected light can be directly incident on the infrared sensor. Therefore, there is no time lag between the time when the optical axis is displaced and the time when the optical axis is detected. Further, since the malfunction of the infrared sensor can be prevented, the deviation of the optical axis of the laser beam can be accurately detected. Further, since the infrared sensor is arranged on the back side of the laser beam blocking member, it does not directly receive the incident laser beam. Therefore, the infrared sensor can be prevented from being damaged and the device can be continuously used.

According to the laser beam optical axis shift detecting device of the next invention, since the surface of the reflecting plate is provided with fine irregularities,
More laser beams can be incident on the infrared sensor. Therefore, the deviation of the optical axis of the laser beam can be detected more accurately.

[0056] According to the laser beam axis deviation detecting apparatus of another aspect of the present invention, since there is provided a filter for transmitting only the laser beam on the surface of the infrared sensor, it is possible to prevent erroneous operation more.

According to the laser beam optical axis deviation detecting device of the next invention, the deviation of the optical axis of the laser beam is detected by the infrared sensor, and a predetermined coping operation is performed based on the detection signal of the infrared sensor. Therefore, continuous irradiation of the laser beam whose optical axis is shifted can be stopped. Therefore, damage to the parts can be prevented.

According to the laser beam optical axis deviation detecting device of the next invention, since the laser beam input resistance performance of the infrared sensor is set as the threshold value of the processing operation, damage to the infrared sensor can be prevented in advance. Therefore, the maintenance work of the laser beam optical axis deviation detecting device can be reduced.

[Brief description of drawings]

FIG. 1 is a front view showing a laser beam optical axis deviation detecting device according to a first embodiment of the present invention.

FIG. 2 is a sectional view of the laser beam optical axis shift detection device shown in FIG.

FIG. 3 is a circuit diagram showing a laser beam optical axis shift detection device.

FIG. 4 is an explanatory diagram showing an installation example of the laser beam optical axis shift detection device.

FIG. 5 is an explanatory diagram showing a case where an optical axis of a laser beam is in a normal position.

FIG. 6 is an explanatory diagram showing a case where an optical axis of a laser beam is displaced.

FIG. 7 is a front view showing a laser beam optical axis deviation detecting device according to a second embodiment of the present invention.

8 is a cross-sectional view showing the laser beam optical axis shift detection device shown in FIG.

FIG. 9 is an explanatory diagram showing a case where the optical axis of the laser beam is deviated.

FIG. 10 is a configuration diagram showing an example of a conventional laser beam optical axis shift detection device.

FIG. 11 is a configuration diagram showing another example of a conventional laser beam optical axis shift detection device.

[Explanation of symbols]

100 laser beam optical axis deviation detection device, 1 base block, 2 laser beam passage hole, 3 wall surface, 4 hole part, 5 infrared sensor, 6 reflector, 7 laser beam passage hole.

Continuation of the front page (56) References JP-A-63-171283 (JP, A) Actual Kaihei 6-65808 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) B23K 26 / 00/26/42

Claims (7)

(57) [Claims] 1. A laser beam blocking member having a laser beam passing hole through which a laser beam passes, and a small diameter laser beam passing hole having a diameter smaller than that of the laser beam passing hole of the laser beam blocking member and having the same central axis. The surface is provided with a taper on the periphery of the laser beam passage hole.
A laser beam light characterized by comprising: a reflection plate having fine irregularities on its inner surface; and an infrared sensor provided at a position where a laser beam can be blocked by a laser beam blocking member and reflected light from the reflection plate can be incident. Axis deviation detection device. 2. A base block having a laser beam passage hole through which a laser beam passes through the center, a hole portion provided on an inner wall surface of the laser beam passage hole of the base block, and the hole portion until the end portion sinks from the wall surface. It has an embedded infrared sensor and a small-diameter laser beam passage hole that has a smaller diameter than the laser beam passage hole of the base block and the same central axis as the laser beam passage hole of the base block. Part is provided and fine unevenness on the surface
A laser beam optical axis shift detection device comprising: a reflector provided with. 3. A ring-shaped reflector plate for reflecting a laser beam, and a ring-shaped reflector plate disposed so as to face the reflector plate such that its central axis substantially coincides with the ring center axis of the reflector plate, and the ring inner diameter is the reflector plate. A laser beam blocking member larger than the ring inner diameter of the laser beam; and an infrared sensor provided on the reflecting plate side of the laser beam blocking member facing the reflecting plate. Detection device. 4. The laser beam optical axis deviation detecting device according to claim 3 , further comprising fine irregularities provided on the surface of the reflecting plate. 5. The laser beam optical axis shift detection device according to claim 1, further comprising a filter that transmits only the laser beam on the surface of the infrared sensor. 6. The infrared ray sensor detects that the optical axis of the laser beam is displaced, and a predetermined coping operation is performed based on a detection signal of the infrared ray sensor. The laser beam optical axis shift detection device according to any one of the above. 7. The laser beam optical axis deviation detecting device according to claim 6, further comprising setting the laser beam withstand capability of the infrared sensor as a threshold value of the processing operation.