JP2015076537A - Laser shutter and laser processing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laser shutter that enables high speed ON/OFF control of a laser beam, and to provide a laser processing device having the laser shutter.SOLUTION: In a laser shutter, rotary drive is possible around an axis passing through the center line of a columnar outer shape, a columnar surface is provided with a plurality of apertures for causing a laser beam to pass into it. The apertures are formed such that the optical path of a laser beam that passes between two of the apertures are offset from the center line of the columnar shape. In the columnar surface, the surface other than the apertures are used as reflector. A laser absorbing body, which absorbs laser beam reflected by the reflector, is arranged. The laser processing device has the laser shutter.

Description

  The present invention relates to a laser shutter installed in the middle of an optical path of a laser beam, and a laser processing apparatus provided with the laser shutter.

  When classifying laser oscillators based on the oscillation principle, there are various types of oscillators such as carbon dioxide laser, YAG laser, and fiber laser. Then, laser light having a wavelength determined by the oscillation principle of the oscillator can be obtained. For example, a YAG laser can obtain a second harmonic, a third harmonic, or a fourth harmonic by an additional wavelength converter.

A continuous wave laser, that is, a CW (Continuous Wave) laser, can irradiate a constant output continuously, and is generally used for thermal processing. By using a CW high-power laser, ablation processing exceeding the ablation threshold can be performed.
Since the pulse wave laser has a high peak pulse energy and a low average energy, it can be processed with less heat influence than the CW laser. The pulse wave laser can change the repetition frequency within a certain range. Some pulse widths are fixed or changeable within a predetermined range.
A CW laser can continuously irradiate a laser, but a quasi-continuous oscillation laser, that is, a QCW (Quasi Continuous Wave) laser, can be switched or modulated in the kHz range.
Each laser device produces different actions and processing results depending on how it is used and the workpiece.

When a laser is applied for industrial use, there is a method in which a workpiece is placed on an XY processing table that moves in the XY direction, and the workpiece is irradiated with laser light for processing.
Specifically, for example, there is a method of processing by scanning a laser beam from a predetermined position with a scanner incorporating a galvanometer.
There is also a method of repeating a pattern by combining a scanner and an XY processing table.
Examples of processing include various processing conditions such as cutting, welding, drilling, surface treatment, modification, scribing, electronic circuit cutting, and semiconductor annealing.

As a laser light ON / OFF control method, there is a method of performing control on the light source side first, for example, a method based on a Q switch by a trigger signal or a gate signal, a method of controlling laser oscillation, and a method of controlling an excitation source. is there.
Further, there is a method in which laser light is blocked by a mechanical shutter or an optical shutter, and laser light irradiation is controlled to be turned on and off.
Specific configurations of mechanical shutters include, for example, a metal plate or metal block that receives laser light to absorb and block energy, and a chopper disk that rotates at high speed (for example, Patent Documents 1 to 5). See reference 2.)
The specific configuration of the optical shutter is, for example, a method of reflecting or reflecting energy by a mirror and supplying or blocking energy with a laser, a method of using a material having a characteristic of changing light transmission characteristics, or a combination of acoustooptic elements. (For example, refer to Patent Documents 3 to 4). An example of high-speed switching is a polygon mirror.

The laser repetition frequency, the moving speed of the processing table, and the moving speed of the laser beam by the scanner are important parameters.
Further, in the case of a pulse wave laser, the thermal effect and processing conditions of the laser change depending on how the pulses overlap.

JP 2001-251005 A JP 2001-308427 A JP 7-181524 A Japanese Patent Laid-Open No. 2002-160086

  The laser light ON / OFF control on the light source side is the principle of laser generation from when the gate signal or trigger signal is turned ON until the power reaches the oscillator excitation circuit through the electric circuit and the laser is emitted. However, there is a delay of microseconds to milliseconds. This differs depending on the type and structure of the laser oscillator. In some cases, the time until the laser stabilizes may be taken into account.

  In the method of controlling ON / OFF of laser light by various mechanical shutters, the angle of a laser absorber such as a black metal block, a metal plate, or graphite is changed to obstruct the laser light path and convert it into heat. Since a shutter using a mechanical barrier plate has a response speed that is as fast as a millisecond, at most, it is generally adopted as a safety device.

  When a rotating disk with a slit, called a chopper disk, is used, it is possible to perform switching at a certain high speed. However, because the chopper disk's rotating disk is thin, if the rotation speed further increases, the rotation becomes unstable due to air resistance, and when high power laser is used, it expands due to temperature rise due to absorption of laser light To do.

  Also, there are optical elements using crystals such as acousto-optic elements and Q switches as means for high-speed switching. However, when these elements are used to turn on / off an ultrashort pulse wave laser such as femtosecond or picosecond, or a laser with a high repetition pulse, there is a problem in response, durability and cost.

Pulse wave lasers that have ultra-short pulses such as femtoseconds and picoseconds and high repetition frequencies have high energy absorption rates for materials such as glass and sapphire, so these materials can be processed. It is suitable for doing.
However, for example, in the case of a pulse wave laser with a pulse width of 1 picosecond to 100 picoseconds and a repetition frequency of several kilohertz to megahertz, and via the control circuit and interface for laser ON / OFF control, it is in the millisecond range Time may be required.
Thus, since it takes time to control the laser ON / OFF, it is difficult to obtain a high-speed shutter capable of synchronizing the laser beam and the material to be processed.

  Even if a laser with a high repetitive pulse is stopped, a large number of pulses are emitted in the meantime. There is no problem with linear processing such as scribing, but local processing and processing of patterns such as broken lines and dotted lines require high-speed ON / OFF control of pulses, and control of laser irradiation for a short time. It is difficult.

In a high-power single-amplifier CW laser and a high peak energy pulse wave laser, complicated control is required for high-speed switching to obtain a burst wave that can be processed with little thermal influence.
Therefore, it has been difficult to realize high-speed switching with the conventional laser processing apparatus.

  In order to solve the above-mentioned problems, the present invention provides a laser shutter that enables high-speed ON / OFF control of laser light. Moreover, the laser processing apparatus provided with this shutter is provided.

  The laser shutter according to the first aspect of the present invention has a cylindrical or spherical outer shape, and can be driven to rotate around an axis passing through the center line of the outer shape. Are provided with a plurality of apertures for allowing laser light to pass through, and an optical path of the laser light passing between two of the plurality of apertures is the center line of the cylindrical shape, Alternatively, a plurality of the apertures are formed so as to be offset from the center of the sphere, and a surface other than the aperture is a reflecting material on the side surface or the spherical surface, and the laser beam reflected by the reflecting material is An absorbing laser absorber is arranged.

  The laser shutter according to the second aspect of the present invention has an outer shape of any one of a hemispherical shape, a conical shape, and a polygonal pyramid shape, and can be driven to rotate around an axis passing through a center line of the outer shape. A plurality of apertures for allowing laser light to pass therethrough are provided on the spherical surface or the side surface of the conical shape or the polygonal pyramid shape, and the surface other than the aperture is a reflector on the spherical surface or the side surface. And a laser absorber that absorbs the laser beam reflected by the reflector is disposed.

  A laser processing apparatus according to the present invention includes a light source unit including a laser oscillator as a light source, a shutter unit having one or more laser shutters that switch between passing and blocking the laser light from the light source unit, and the shutter unit. A processing part is provided for irradiating the workpiece with the laser beam that has passed to process the workpiece, and each of the laser shutters of the shutter part is a configuration of the laser shutter of the present invention.

According to the configuration of the laser shutter of the first aspect of the present invention described above, a plurality of shafts can be driven to rotate around the axis, and the laser beam can be passed through the cylindrical side surface or spherical spherical surface. An aperture is provided. As a result, when the laser light hits the aperture, the laser light can pass from the aperture into the shutter and be emitted from the other aperture.
Further, the surface other than the aperture is a reflective material, and a laser absorber that absorbs the laser light reflected by the reflective material is disposed. Thereby, when the laser light hits a portion other than the aperture, it can be reflected by the reflecting material and absorbed by the laser absorber.
Then, by rotating the shutter, it becomes possible to switch between a state in which the laser light passes through the aperture and a state in which the laser light is reflected and blocked by the reflecting material, and the laser light is turned on / off. be able to. At this time, if the shutter is driven at a high speed, the laser light can be controlled to be turned on and off at a high speed.
In addition, the outer shape of the shutter is a cylindrical or spherical rotating body centered on the center line, has a solid three-dimensional structure, and is driven to rotate around an axis that passes through the center line. It is hard to receive. Thereby, even if the rotation speed of the shutter is increased, the shutter can be rotated stably.
Further, when blocking the laser beam, the laser beam can be reflected by the reflecting material on the surface of the shutter and absorbed by the laser absorber. Thereby, compared with the case where a chopper disk is used, the amount of laser light absorbed by the shutter can be greatly reduced, and a high-power laser can be used as a light source.
Further, the aperture is formed so that the optical path of the laser beam passing between two of the plurality of apertures is offset from the center line of the cylindrical shape or the center of the spherical shape. As a result, if the light source (laser oscillator, etc.) is arranged so that the laser beam input to the shutter passes through the optical path between the apertures, the laser beam hits the part of the reflective material other than the aperture. Therefore, there is almost no amount of light that is reflected and returned to the light source unit side. Thereby, it becomes possible to prevent the light source part from being damaged.

According to the above-described configuration of the laser shutter of the second aspect of the present invention, the laser shutter can be driven to rotate around the axis, and the laser beam is allowed to pass through the hemispherical spherical surface, the conical surface, or the side surface of the conical shape. A plurality of apertures are provided. As a result, when the laser light hits the aperture, the laser light can pass from the aperture into the shutter and be emitted from the other aperture.
Further, the surface other than the aperture is a reflective material, and a laser absorber that absorbs the laser light reflected by the reflective material is disposed. Thereby, when the laser light hits a portion other than the aperture, it can be reflected by the reflecting material and absorbed by the laser absorber.
Then, by rotating the shutter, it becomes possible to switch between a state in which the laser light passes through the aperture and a state in which the laser light is reflected and blocked by the reflecting material, and the laser light is turned on / off. be able to. At this time, if the shutter is driven at a high speed, the laser light can be controlled to be turned on and off at a high speed.
In addition, the outer shape of the shutter is a hemispherical or conical rotating body centered on the center line, or a polygonal pyramid, has a solid three-dimensional structure, and is driven to rotate around an axis passing through the center line. Less susceptible to air resistance during rotation. Thereby, even if the rotation speed of the shutter is increased, the shutter can be rotated stably.
Further, when blocking the laser beam, the laser beam can be reflected by the reflecting material on the surface of the shutter and absorbed by the laser absorber. Thereby, compared with the case where a chopper disk is used, the amount of laser light absorbed by the shutter can be greatly reduced, and a high-power laser can be used as a light source.
In the shutter, an aperture is formed on the side surface of a hemispherical spherical surface, a conical shape, or a polygonal pyramid shape. As a result, if the light source part is arranged so that the laser light input to the shutter passes through the optical path between the apertures, when the laser light hits the part of the reflective material other than the apertures, it will not hit vertically. There is almost no amount of light reflected and returned to the light source unit side. Thereby, it becomes possible to prevent the light source part from being damaged.

According to the configuration of the laser processing apparatus of the present invention described above, a light source unit, a shutter unit having one or more laser shutters, and a processing unit are provided, and each laser shutter of the shutter unit is for the laser of the present invention. This is the shutter configuration. As a result, the laser light from the light source unit can be ON / OFF controlled by the shutter of the shutter unit, and if the shutter is rotated at a high speed, the laser light can be ON / OFF controlled at a high speed. And since it can be rotated stably even if the rotation speed of the shutter is increased, ON / OFF control of laser light can be performed stably at high speed.
In addition, a high-power laser can be used as the light source of the light source unit.
Furthermore, it becomes possible to prevent the light source unit from being damaged by the reflected light.

According to the above-described present invention, ON / OFF control of laser light can be stably performed at high speed.
In addition, since optical switches such as mirrors and acousto-optic elements are not used in the laser light path, the laser output is less affected by heat by reducing the average output without changing the peak output value or optical quality of the laser oscillator. A processing device can be realized.

The laser shutter and laser processing apparatus of the present invention can be applied to a laser oscillator of any configuration of CW laser or pulse wave laser, single mode or multimode, and can be easily applied to most existing laser oscillators. It is possible.
Thereby, in a laser processing apparatus, it becomes possible to expand processing conditions.

It is a schematic block diagram (perspective view) of the laser processing apparatus of the 1st Embodiment of this invention. It is a figure which shows the state by which the laser beam was interrupted | blocked by the 1st shutter unit of FIG. It is a figure which shows the state by which the laser beam was interrupted | blocked by the 2nd shutter unit of FIG. It is a timing chart at the time of using a CW laser for the laser oscillator of FIG. It is a timing chart at the time of using a pulse wave laser for the laser oscillator of FIG. A and B It is sectional drawing of the shutter of the laser processing apparatus of the 2nd Embodiment of this invention. In 2nd Embodiment, it is a timing chart at the time of using CW laser for a laser oscillator. In 2nd Embodiment, it is a timing chart at the time of using a pulse wave laser for a laser oscillator. A, B It is sectional drawing of the shutter of the modification with respect to 2nd Embodiment. A, B It is sectional drawing of the shutter of the modification with respect to 2nd Embodiment. It is a schematic block diagram (perspective view) of the laser processing apparatus of the 3rd Embodiment of this invention. A and B It is a schematic block diagram of the laser processing apparatus of the 3rd Embodiment of this invention. A and B It is a schematic block diagram (perspective view) of the laser processing apparatus of the 4th Embodiment of this invention. A and B It is a schematic block diagram (perspective view) of the laser processing apparatus of the 5th Embodiment of this invention.

Hereinafter, modes for carrying out the invention (hereinafter referred to as embodiments) will be described.
The description will be given in the following order.
1. First Embodiment 2. FIG. Second Embodiment 3. FIG. Modified example 4 of the second embodiment Third embodiment 5. Fourth Embodiment Fifth embodiment

<1. First Embodiment>
FIG. 1 shows a schematic configuration diagram (perspective view) of the laser processing apparatus according to the first embodiment of the present invention.
A laser processing apparatus 1 shown in FIG. 1 includes a light source unit that generates laser light, a shutter unit that controls ON / OFF of laser light from the light source unit, and processing the workpiece by irradiating the workpiece with the laser beam. The processing part which performs is provided.

The light source section includes a laser oscillator 2 that is a light source and a beam expander 4 that expands and shapes the beam diameter of the collimated laser light 3 oscillated from the laser oscillator 2.
The shutter unit includes a first shutter unit 11 and a second shutter unit 31 that are arranged above and below, and a control device 57 that controls these shutter units 11 and 31. With these configurations, ON / OFF control is performed by switching between passing and blocking of the laser light from the light source unit.
The processing unit includes an XY table 53 on which a workpiece 52 is placed and movable in the X and Y directions, and an optical system unit 50 that irradiates the workpiece 52 with laser light.

As the laser oscillator 2 of the light source unit, various laser oscillators can be used.
Either a CW laser or a pulse wave laser can be used for the laser oscillator 2, and most existing laser oscillators can be used regardless of single mode or multimode. Various lasers such as a solid-state laser, a semiconductor laser, and a laser excitation laser can be used as the laser constituting the laser oscillator. An appropriate laser oscillator is used in accordance with the material of the workpiece 52 to be processed and the wavelength of the laser beam used for processing.
The beam expander 4 expands the diameter of the collimated laser beam 3 emitted from the laser oscillator 2 to be an input laser 12 that is input to the first shutter unit 11.

  The first shutter unit 11 is provided with an aperture 15 through which laser light passes, and is configured to be rotatable around a central shaft 21 and a spindle motor that rotates the cylindrical shutter 14. 24. Further, a laser absorption block 22 provided obliquely above the cylindrical shutter 14 is provided.

The cylindrical shutter 14 has a cylindrical shape with a cylindrical outer shape and a hollow inside, and the surface is formed of a reflective material 19. The cylindrical shutter 14 is provided with a shaft 21 that passes through the center line of the outer shape, and is driven to rotate about the shaft 21 by a spindle motor 24 as indicated by an arrow 20.
As will be described in detail later, the reflecting material 19 may be formed by using a material such as metal to form the cylindrical shutter 14 itself, and the reflecting material 19 may be formed by forming a reflecting film on the surface of the material of the cylindrical shutter 14. 19 is also acceptable.

An air bearing 23 is provided at a connecting portion between the shaft 21 and the spindle motor 24, and the shaft 21 is held by a bearing of the air bearing 23.
The cylindrical shutter 14 and the spindle motor 24 are connected by a coupler 25 provided on the shaft 21.
An interface 26 is provided on the right side surface of the spindle motor 24 in the drawing. A water-cooled pipe, an air bearing air pipe, and an electric system wiring are connected between the interface 26 and the control device 57, respectively.
The spindle motor 24 is controlled by the control device 57 to control the number of rotations thereof and to synchronize with the second shutter unit 31.
When the laser energy is strong, it is desirable to cool the cylindrical shutter 14 and the shaft 21.

Two apertures 15 are formed on the side surface of the cylindrical shutter 14, and laser light can pass between these apertures 15.
The size of the aperture 15 of the cylindrical shutter 14 is slightly larger than the luminous flux of the passing laser beam.
The two apertures 15 are formed such that the optical path of the laser beam passing therethrough is offset from the center line of the cylindrical shutter 14. That is, the line connecting the two apertures 15 is not a diameter of the cylinder but a string.
The light source unit and the cylindrical shutter 14 are relatively arranged so that the laser beam passes when the cylindrical shutter 14 rotates and the two apertures 15 are moved up and down. Accordingly, the position where the input laser 12 hits the cylindrical shutter 14 is offset from directly above the center line of the cylindrical shutter 14 corresponding to the position of the aperture 15.

Due to the rotation of the cylindrical shutter 14, the position of the cylindrical shutter 14 to which the input laser 12 hits changes such as the aperture 15 or a portion other than the aperture 15.
When the input laser 12 hits the aperture 15, it passes through the aperture 15 and is emitted from the lower aperture 15 to become the output laser 13.
When the input laser 12 hits a portion other than the aperture 15, the input laser 12 is reflected by the reflecting material 19 on the surface of the cylindrical shutter 14. At this time, since the input laser 12 is irradiated to a position offset from directly above the center line of the cylindrical shutter 14, the input laser 12 reflected by the reflecting material 19 does not return to the incident side, and the laser absorption block The laser is absorbed by the laser absorption block 22.

The cylindrical shutter 14 can be formed of, for example, metal, ceramic, graphite, synthetic resin, or the like.
Alternatively, a highly reflective material may be used for the cylindrical shutter 14 to be used as the reflective material 19 as it is, and a material having a low reflectance is used for the cylindrical shutter 14 and the surface is reflected by a highly reflective material. A film may be formed as the reflective material 19.
The shaft 21 of the cylindrical shutter 14 may be configured to be connected to the outside of the cylindrical shutter 14 or may be configured to penetrate the inside of the cylindrical shutter 14. The cylindrical shutter 14 is preferably reduced in weight in order to cope with high-speed rotation, and it is desirable to devise a balance in order to improve rotation accuracy.

Furthermore, in order to prevent irregular reflection of the laser light on the inner surface of the cylindrical shutter 14, it is desirable that an absorbing material that absorbs the laser light is formed on the inner surface of the cylindrical shutter 14. For example, when the input laser 12 hits the range of the upper aperture 15 due to the rotation of the cylindrical shutter 14, most of the laser light entering the cylindrical shutter 14 passes through the lower aperture 15. It is impossible to hit the inner wall of the cylindrical shutter 14. At this time, if the inner surface of the cylindrical shutter 14 is a reflecting material, the inner surface of the cylindrical shutter 14 is irregularly reflected, and unnecessary laser light is emitted from the two apertures 15 in an undesired direction.
When a material having a high reflectance is used for the cylindrical shutter 14, an absorbent material is coated on the inner surface of the cylindrical shutter 14.
When an absorber is used for the cylindrical shutter 14, the inner surface is left as it is.
Further, the material of the cylindrical shutter 14 is not high in reflectance and absorption, but a light and strong material may be used to form a reflective film on the surface and coat the inner surface with the absorbent.

The laser absorption block 22 is provided with a cooler such as air cooling, water cooling, or a Peltier element according to the intensity of the laser energy.
Further, the laser absorption block 22 may be configured to also serve as a sensor for the laser power meter. In such a configuration, the laser power can be measured at a place where the laser is constantly reflected.

  The second shutter unit 31 is provided with three types of apertures 35, 36, and 37 through which laser light passes, and is configured to be rotatable around a central axis 41, and a cylindrical shutter A spindle motor 44 that rotates the spindle 34 and a rack and pinion gear 48 that moves the cylindrical shutter 34 and the spindle motor 44 are provided. Further, a laser absorption block 42 provided obliquely above the cylindrical shutter 34 is provided.

  The output laser 13 emitted from the cylindrical shutter 14 of the first shutter unit 11 is input as the input laser 32 to the cylindrical shutter 34 of the second shutter unit 31.

  The cylindrical shutter 34 has a cylindrical shape with a cylindrical outer shape and a hollow inside, and the surface is formed of a reflective material 39. The cylindrical shutter 34 is provided with a shaft 41 passing through the center line of the outer shape, and is driven to rotate about the shaft 41 as indicated by an arrow 40 by a spindle motor 44.

An air bearing 43 is provided at a connecting portion between the shaft 41 and the spindle motor 44, and the shaft 41 is held by a bearing of the air bearing 43.
The cylindrical shutter 34 and the spindle motor 44 are connected by a coupler 45 provided on the shaft 41.
An interface 46 is provided on the right side surface of the spindle motor 44 in the drawing. A water cooling pipe, an air bearing air pipe, and an electric system wiring are connected between the interface 46 and the control device 57.
The spindle motor 44 is controlled by the control device 57 to control the number of rotations and control the synchronization with the first shutter unit 11.
When the laser energy is strong, it is desirable to cool the cylindrical shutter 34, the shaft 41, and the like.

Two types of apertures 35, 36, and 37 having different opening sizes and shapes are formed on the side surface of the cylindrical shutter 34, and laser light is transmitted between the apertures 35, 36, and 37. Can pass through. Each of the apertures 35, 36, and 37 is formed such that the optical path of the laser beam passing therethrough is offset from the center line of the cylindrical shutter 34. That is, the line connecting the two apertures 35, 36, and 37 is not a diameter of the cylinder but a string.
Then, the cylindrical shutter 14 and the second shutter of the first shutter unit 11 are passed so that the laser beam passes when the cylindrical shutter 34 rotates and the two apertures 35, 36, and 37 move up and down. A cylindrical shutter 34 of the unit 31 is relatively disposed. Thereby, the position where the input laser 32 hits the cylindrical shutter 34 is offset from directly above the center line of the cylindrical shutter 34 corresponding to the positions of the apertures 35, 36, and 37.

Due to the rotation of the cylindrical shutter 34, the position of the cylindrical shutter 34 to which the input laser 32 hits changes such as the apertures 35, 36, 37, or portions other than the apertures 35, 36, 37.
When the input laser 32 hits the apertures 35, 36, 37, it passes through the apertures 35, 36, 37 and is emitted from the lower apertures 35, 36, 37 to become the output laser 33.
When the input laser 32 hits a portion other than the apertures 35, 36, and 37, the input laser 32 is reflected by the reflecting material 39 on the surface of the cylindrical shutter 34. At this time, since the input laser 32 is irradiated to a position offset from directly above the center line of the cylindrical shutter 34, the input laser 32 reflected by the reflecting material 39 does not return to the incident side, and the laser absorption block. The laser is absorbed by the laser absorption block 42.

The cylindrical shutter 34 can be formed of, for example, metal, ceramic, graphite, synthetic resin, or the like.
Further, a material having high reflectivity may be used for the cylindrical shutter 34 and may be used as the reflecting material 39 as it is, and a material having low reflectivity is used for the cylindrical shutter 34 and the surface is reflected by a material having high reflectivity. A film may be formed as the reflector 39.
The shaft 41 of the cylindrical shutter 34 may be configured to be connected to the outside of the cylindrical shutter 34 or may be configured to penetrate through the inside of the cylindrical shutter 34. The cylindrical shutter 34 is preferably reduced in weight in order to cope with high-speed rotation, and it is desirable to devise a balance in order to improve rotation accuracy.

  Further, in order to prevent irregular reflection of the laser light on the inner surface of the cylindrical shutter 34, it is desirable that an absorbing material that absorbs the laser light is formed on the inner surface of the cylindrical shutter 34. The configuration of the absorber can be the same as that of each aspect described in the cylindrical shutter 14 of the first shutter unit 11.

The laser absorption block 42 is provided with a cooler such as air cooling, water cooling, or a Peltier element, similarly to the laser absorption block 22 of the first shutter unit 11, depending on the intensity of the laser energy.
Further, the laser absorption block 42 may be configured to also serve as a laser power meter sensor. In such a configuration, the laser power can be measured at a place where the laser is constantly reflected.

Further, the second shutter unit 31 can move the cylindrical shutter 34 and the spindle motor 44 by the rack and pinion gear 48 in the left-right direction in the drawing as indicated by the arrow 49. Thereby, the aperture through which the input laser 32 passes can be switched between the three types of apertures 35, 36, and 37.
The left aperture 35 is formed to be slightly larger than the luminous flux of the laser beam passing therethrough, like the aperture 15 of the cylindrical shutter 14 of the first shutter unit 11.
The central aperture 36 is formed in a rectangular shape that is sufficiently larger than the luminous flux of the laser beam that passes therethrough.
The right-side aperture 37 is formed in a fan shape whose opening width becomes narrower toward the left side. With this configuration, by changing the position where the input laser 32 strikes the aperture 37 by the operation of the rack and pinion gear 48, the aperture width of the aperture 37 with respect to the input laser 32 is changed, and the generation timing of the burst wave laser is changed. Is possible. By continuously operating the rack and pinion gear 48, it is possible to continuously change the generation timing of the burst wave laser. Even if a diamond-shaped aperture is formed instead of the fan-shaped aperture 37, the same effect can be obtained.
In FIG. 1, there is an aperture 36 in the center of the cylindrical shutter 34 at a position through which the input laser 32 passes. The input laser 32 passes through the aperture 36 and is emitted from the lower aperture 36 to become an output laser 33. ing.

The output laser 33 emitted from the cylindrical shutter 34 of the second shutter unit 31 is input to the optical system unit 50 of the processing unit. The optical system unit 50 includes an objective lens or a scanner.
The output laser 33 input to the optical system unit 50 is focused by the optical system unit 50 to become a condensing laser 51. This condensing laser 51 forms an image and is irradiated onto the workpiece 52, and the workpiece is processed. The material 52 is processed.
Then, the position where the workpiece 52 is processed is changed by moving the XY table 53 on which the workpiece 52 is placed in the X-axis direction (arrow 54) or the Y-axis direction (arrow 55). Can do.

  In the first shutter unit 11 and the second shutter unit 31, the cylindrical shutters 14 and 34 are rotationally driven, and the positions of the apertures 15, 35, 36, and 37 are changed, so that the laser light is ON / OFF controlled. The Thereby, the condensing laser 51 irradiated to the workpiece 52 can be a burst wave laser.

  A laser beam is scanned on the workpiece 52 by a combination of the operations of the cylindrical shutters 14 and 34, the operation of the optical system unit 50, and the operations of the X-Y table 53 in the X-axis direction 54 and the Y-axis direction 55. By doing so, it is possible to obtain a laser processing result 56 in which continuous lines, dotted lines, or broken lines are combined.

FIG. 1 shows a state in which the laser beam from the light source unit passes through the first shutter unit 11 and the second shutter unit 31 and is irradiated on the workpiece 52.
In contrast, FIG. 2 shows a state in which the laser light is blocked by the first shutter unit 11, and FIG. 3 shows a state in which the laser light is blocked by the second shutter unit 31. 2 and 3, illustration of the laser oscillator 2, the control device 57, and the like is omitted.
In FIG. 2, in the cylindrical shutter 14 of the first shutter unit 11, the input laser 12 hits a portion other than the aperture 15. Then, the input laser 12 is reflected by the reflecting material 19 on the surface of the cylindrical shutter 14 to become reflected light 18 that is directed obliquely upward, and is absorbed by the laser absorption block 22.
In FIG. 3, in the cylindrical shutter 34 of the second shutter unit 31, the input laser 32 hits a portion other than the apertures 35, 36, and 37. Then, the input laser 32 is reflected by the reflecting material 39 on the surface of the cylindrical shutter 34 to be reflected light 38 obliquely upward, and is absorbed by the laser absorption block 42. In FIG. 3, similarly to FIG. 1, there is an aperture 36 at the center of the cylindrical shutter 34 at a position where the input laser 32 passes.

Next, ON / OFF control of laser light when a CW laser is used as the laser oscillator 2 in FIG. 1 will be described.
FIG. 4 shows a timing chart when a CW laser is used as the laser oscillator 2 in FIG. In FIG. 4, the cylindrical shutter 34 of the second shutter unit 31 is filled with a portion other than the through passage formed between the two apertures 36, and the surface is a reflecting material 39. The cylindrical shutter 34 may have a cylindrical configuration in which the surface is a reflective material 39 and the inside is completely hollow.

In the CW laser, when the gate signal OFF60 is changed to the gate signal ON61, the output of the CW laser is changed from the CW laser OFF62 to the CW laser ON63.
The cylindrical shutter 14 of the first shutter unit 11 changes from the left to the right in the figure (arrow 64) according to its rotation (arrow 20). Thereby, in the state of the CW laser ON 63, a CW burst wave 65 determined by the size of the diameter of the aperture 15 of the cylindrical shutter 14 and the rotational speed of the cylindrical shutter 14 is obtained.
Subsequently, the laser output 13 from the cylindrical shutter 14 of the first shutter unit 11 is irradiated to the cylindrical shutter 34 of the second shutter unit 31 as a laser input 32.
The cylindrical shutter 34 of the second shutter unit 31 changes from the left to the right in the figure (arrow 66) according to its rotation (arrow 40). As a result, the laser output 33 is turned on / off depending on the opening degree of the aperture 36 of the cylindrical shutter 34 and the speed of rotation (arrow 40), and a burst wave 67 by the CW laser is obtained.
In FIG. 4, five equally spaced pulses are obtained in the CW burst wave 65, and three pulses are obtained in the burst wave 67 because some of the pulses are blocked by the cylindrical shutter 34. Yes.

In the timing chart of FIG. 4, the first-stage cylindrical shutter 14 rotates at a high speed, and the second-stage cylindrical shutter 34 rotates at a low speed.
For example, a burst wave 67 having a peak energy of 2 kW can be obtained by using a CW fiber laser having a maximum output of 2 kW for the laser oscillator 2.

Next, ON / OFF control of laser light when a pulse wave laser is used as the laser oscillator 2 in FIG. 1 will be described.
FIG. 5 shows a timing chart when a pulse wave laser is used as the laser oscillator 2 in FIG.

In the pulse wave laser, when the gate signal OFF 60a is changed to the gate signal ON 61a, the output of the pulse wave laser is changed from the pulse wave laser OFF 62a to the pulse wave laser ON 63a.
As in the case of FIG. 4, the cylindrical shutter 14 of the first shutter unit 11 transitions from the left to the right in the figure (arrow 64) according to its rotation (arrow 20). Thereby, in the state of the pulse wave laser ON 63a, the burst wave 65a of the pulse wave laser, which is determined by the size of the diameter of the aperture 15 of the cylindrical shutter 14 and the rotational speed of the cylindrical shutter 14, is obtained.
Subsequently, the laser output 13 from the cylindrical shutter 14 of the first shutter unit 11 is irradiated to the cylindrical shutter 34 of the second shutter unit 31 as a laser input 32.
As in the case of FIG. 4, the cylindrical shutter 34 of the second shutter unit 31 transitions from the left to the right in the drawing (arrow 66) according to its rotation (arrow 40). As a result, the laser output 33 is turned on / off depending on the opening degree of the aperture 36 of the cylindrical shutter 34 and the speed of rotation (arrow 40), and a burst wave 67a by a pulse wave laser is obtained.
In FIG. 5, five sets of equally-spaced pulse groups are obtained in the burst wave 65a of the pulse wave laser, and in the burst wave 67a, a part of the pulse group is cut off by the cylindrical shutter 34, so that 3 Two pulse groups are obtained.

In the timing chart of FIG. 5, the first-stage cylindrical shutter 14 rotates at a high speed, and the second-stage cylindrical shutter 34 rotates at a low speed.
For example, a pulse wave fiber laser having a peak energy of 6 μJ and a repetition frequency of 4 MHz is used for the laser oscillator 2 to obtain a burst wave 65a and a burst wave 67a having a low repetition frequency.

In FIG. 5, the enlarged waveform 71 of the pulse wave of the laser oscillator 2, the enlarged waveform 72 of the pulse wave laser 65 a obtained by the first-stage cylindrical shutter 14, and the second-stage cylindrical shutter 34 are obtained. An enlarged waveform 73 of the burst wave 67a is shown.
As shown in the enlarged waveform 71, the pulse wave of the laser oscillator 2 has a uniform pulse height. On the other hand, the burst wave 65a of the pulsed laser shown in the enlarged waveform 72 and the burst wave 67a shown in the enlarged waveform 73 are pulse heights when the laser light is applied to the inside and outside of the aperture 15 of the cylindrical shutter 14. Is low.

The rotational speed of the cylindrical shutter 14 of the first shutter unit 11 is selected from an ultra-low speed of 1 revolution or less per minute to an ultra-high speed of 200,000 revolutions per minute as required. As a result, a shutter function and a wide range of burst modes can be easily obtained, and it is possible to cope with various processing.
For example, if the spindle motor of 200,000 revolutions per minute is 3,333 revolutions per second, and the number of apertures 15 of the cylindrical shutter 14 of the first shutter unit 11 is two as shown in FIG. A repetition frequency of 3.3 kHz is obtained.

  According to the configuration of the laser processing apparatus 1 of the above-described embodiment, the surfaces are the reflecting materials 19 and 39, and the apertures 15, 35, 36, and 37 through which the laser light passes are formed on the side surfaces and pass through the center line. Cylindrical shutters 14 and 34 rotating around the shafts 21 and 41 are provided between the light source unit and the processing unit. Therefore, by rotating the cylindrical shutters 14 and 34, a state in which the laser light passes through the apertures 15, 35, 36, and 37, and a state in which the laser light is reflected by the reflectors 19 and 39 and blocked. It becomes possible to switch. If at least one of the two cylindrical shutters 14 and 34 is rotated at a high speed, the laser light can be switched ON / OFF at a high speed.

  Further, the cylindrical shutters 14 and 34 are rotating bodies centered on the shafts 21 and 41, have a solid three-dimensional structure, and rotate around the shafts 21 and 41, so that the air resistance during rotation is reduced. Not easily affected. Thereby, even if the rotational speed of the cylindrical shutters 14 and 34 is increased, the cylindrical shutters 14 and 34 can be rotated stably.

  Further, when blocking the laser light, the laser light is reflected by the reflectors 19 and 39 on the surfaces of the cylindrical shutters 14 and 34, and the reflected lights 18 and 38 are absorbed by the laser absorption blocks 22 and 42. Yes. Thereby, compared with the case where a chopper disk is used, the amount of laser light absorbed by the cylindrical shutters 14 and 34 can be greatly reduced, and a high-power laser can be used for the laser oscillator 2. It becomes possible.

  Further, since the optical path of the laser light is offset from the center line of the cylindrical shutters 14 and 34, the input lasers 12 and 32 do not hit perpendicularly when they hit the reflectors 19 and 39. There is almost no amount of light returning to the part side. Thereby, damage to the laser oscillator 2 can be prevented. In particular, when a fiber laser is used for the laser oscillator 2, it is effective because it is easily affected by reflected waves.

A wide range of ON / OFF control is achieved by a combination of the CW gate signal ON61 or the pulsed laser gate signal ON61a, the shape of the apertures 15, 35, 36, and 37, and the control of the control device 57 and the rack and pinion gear 48. Is possible. Thereby, a burst wave having an arbitrary pulse width and pulse interval can be obtained, and for example, the workpiece 52 can be processed with a fine pattern such as a dotted line or a broken line.
In particular, by adopting a burst mode in which burst waves 65a and 67a in which a high-frequency pulse train is repeated at a low frequency cycle as shown in FIG. Processing becomes possible.

  Further, for example, when pattern processing is performed on the surface of the metal that is the workpiece 52 by the burst wave obtained by the laser processing apparatus 1 of the present embodiment, fine grooves may be formed on the surface of the metal. It becomes possible. And adhesiveness of a metal and another material through an adhesive agent can be improved by an adhesive agent entering this groove | channel.

In the laser processing apparatus of the present embodiment, it is also possible to provide a bearing instead of the air bearings 23 and 43 so that the shafts 21 and 41 of the cylindrical shutters 14 and 34 are held by the bearings. .
However, when rotating the shutter at a very high speed, it is desirable to use an air bearing rather than a bearing for the shaft of the shutter or spindle motor.

In the present embodiment, the cylindrical shutters 14 and 34 are used for the first shutter unit 11 and the second shutter unit 31, but a cylindrical shutter whose inside is not hollow is used for each shutter unit. You may do it. Moreover, you may use the shutter of the structure which made one part hollow among cylindrical insides.
When a cylindrical shutter is used, a through path that connects two apertures on the surface of the cylindrical shutter is formed inside the cylindrical shutter. Then, it is desirable to form a cylindrical shutter with an absorbing material or coat the absorbing material on the inner wall of the through passage so that the laser beam is not diffusely reflected on the inner wall of the through passage.
When the shutter is used at a high speed, it is desirable to use a light metal for the shutter or reduce the weight by processing the shutter.

In the present embodiment, as described in FIGS. 4 and 5, the cylindrical shutter 14 of the first shutter unit 11 is rotated at a high speed, and the cylindrical shutter 34 of the second shutter unit 31 is rotated at a low speed. It was.
The arrangement of these shutters may be reversed so that the shutter of the first shutter unit on the light source unit side is rotated at a low speed and the shutter of the second shutter unit on the processing unit side is rotated at a high speed.
Three or more shutter units may be arranged.

<2. Second Embodiment>
Next, schematic configuration diagrams of a second embodiment of the laser processing apparatus of the present invention are shown in FIGS. 6A and 6B. 6A and 6B show sectional views (sectional views in a plane perpendicular to the center line) of the shutter 14X of the first shutter unit 11 in the present embodiment.
The other components of the laser processing apparatus (light source unit, second shutter unit, processing unit) are not shown, but are the same as the laser processing apparatus 1 of the first embodiment shown in FIG. The configuration is as follows.

As shown in FIGS. 6A and 6B, the shutter 14X of the present embodiment has an intermediate shape between a cylindrical shape and a cylindrical shape, and is filled with a material at a certain thickness on the way from the outer cylindrical surface. The inside is hollow.
The surface of the shutter 14X is a reflective material 19 as in the cylindrical shutter 14 of the first embodiment.

Four apertures 15X are provided at approximately equal intervals on the circumference of the side surface of the shutter 14X.
The size of the aperture 15X is a little larger than the luminous flux of the laser light, like the aperture 15 of the first embodiment in FIG. Further, four through passages 27 are formed through the filled material so as to connect the apertures 15X.
Note that the inner wall of the through passage 27 is desirably an absorbent that absorbs laser light. Therefore, the material that fills the cylinder is used as an absorbent, or the inner wall of the through passage 27 is coated with the absorbent.

  In the case of the configuration of the present embodiment, when the through passage 27 is in the vertical direction, that is, when the position of the aperture 15X is obliquely about 45 ° from the center line, the laser light passes through the through passage 27. As described above, the light source unit and the first shutter unit 11 are arranged. Therefore, when the input laser 12 is reflected by the reflecting material 19 on the surface of the shutter 14X, the reflected light 18 travels almost directly as shown in FIG. 6B, so that the laser absorption block 22 is connected to the shutter 14X. It is arranged next to the irradiation position.

In the shutter 14X of the present embodiment, four apertures 15X are formed at equal intervals, and there are four through passages 27, so that the laser light passes four times by one rotation of the shutter 14X.
In the first embodiment, since the laser beam passes once by one rotation of the cylindrical shutter 14, in this embodiment, the same number of rotations of the shutter is used, which is four times that of the first embodiment. A pulse or pulse group will be obtained.

FIG. 7 shows a timing chart in the case where a CW laser is used as the laser oscillator in this embodiment.
The shutter 14X of the first shutter unit 11 changes from the left to the right in the drawing (arrow 68) according to its rotation (arrow 20). Thereby, in the state of the CW laser ON 63, a CW burst wave 69 determined by the size of the diameter of the aperture 15X of the shutter 14X and the rotation speed of the shutter 14X is obtained.
At every quarter rotation of the shutter 14X, the laser beam passes through the through path 27, and a pulse is obtained in the CW burst wave 69. FIG. 7 shows five pulses, but two pulses at the boundary are shown, so four pulses are obtained as the CW burst wave 69 while the shutter 14X rotates once.

Subsequently, the laser output 13 from the shutter 14 </ b> X of the first shutter unit 11 is used as a laser input 32 to irradiate the cylindrical shutter 34 of the second shutter unit 31.
The cylindrical shutter 34 of the second shutter unit 31 changes from the left to the right in the figure (arrow 66) according to its rotation (arrow 40). As a result, the laser output 33 is turned on / off depending on the opening degree of the aperture 36 of the cylindrical shutter 34 and the speed of rotation (arrow 40), and a burst wave 70 by the CW laser is obtained.
In FIG. 7, four equally-spaced pulses are obtained in the CW burst wave 69 during one rotation period (one cycle) 74 of the shutter 14 </ b> X. In the burst wave 70, the fourth pulse is obtained by the cylindrical shutter 34. Three pulses are obtained because the pulses are cut off.

In the timing chart of FIG. 7, the first-stage shutter 14X rotates at a high speed, and the second-stage cylindrical shutter 34 rotates at a low speed.
For example, a burst wave 69 having a peak energy of 2 kW can be obtained by using a CW fiber laser having a maximum output of 2 kW for the laser oscillator 2.

Further, FIG. 8 shows a timing chart when a pulse wave laser is used as the laser oscillator in this embodiment.
As in the case of FIG. 7, the shutter 14X of the first shutter unit 11 transitions from the left to the right in the drawing (arrow 68) according to its rotation (arrow 20). Thereby, in the state of the pulse wave laser ON 63a, the burst wave 69a of the pulse wave laser determined by the size of the diameter of the aperture 15X of the shutter 14X and the rotation speed of the shutter 14X is obtained. Although FIG. 8 shows five pulse groups, since two pulse groups at the boundary are shown, there are four pulse groups as a burst wave 69a of the pulse wave laser during one rotation of the shutter 14X. can get.

Subsequently, the laser output 13 from the shutter 14 </ b> X of the first shutter unit 11 is used as a laser input 32 to irradiate the cylindrical shutter 34 of the second shutter unit 31.
As in the case of FIG. 7, the cylindrical shutter 34 of the second shutter unit 31 transitions from the left to the right in the drawing (arrow 66) according to its rotation (arrow 40). As a result, the laser output 33 is turned on / off depending on the opening degree of the aperture 36 of the cylindrical shutter 34 and the speed of rotation (arrow 40), and a burst wave 70a by a pulsed laser is obtained.
In FIG. 8, in the period of one rotation (one cycle) 74 of the shutter 14X, four equal-interval pulse groups are obtained in the burst wave 69a. In the burst wave 70, a is four by the cylindrical shutter 34. Three pulse groups are obtained by blocking the eye pulse groups.

In the timing chart of FIG. 8, the first-stage shutter 14X rotates at a high speed, and the second-stage cylindrical shutter 34 rotates at a low speed.
For example, a burst wave 69a and a burst wave 70a having a low repetition frequency can be obtained by using a pulse wave fiber laser having a peak energy of 6 μJ and a repetition frequency of 4 MHz.

  According to the configuration of the laser processing apparatus of the present embodiment, the shutter 14X of the first shutter unit has the surface as the reflecting material 19, the aperture 15X through which the laser beam passes is formed on the side surface, and the axis passes through the center line. This is a cylindrical configuration that rotates around 21. Therefore, by rotating the shutter 14X, it is possible to switch between a state in which the laser light passes through the aperture 15X and a state in which the laser light is reflected and blocked by the reflecting material 19. If the shutter 14X is rotated at a high speed, the laser light can be switched on and off at a high speed.

  In addition, the shutter 14X is a rotating body centered on the shaft 21, has a solid three-dimensional structure, and rotates around the shaft 21, so that it is not easily affected by air resistance during rotation. Thereby, even if the rotational speed of the shutter 14X is increased, it can be stably rotated.

  Further, when blocking the laser light, the laser light is reflected by the reflecting material 19 on the surface of the cylindrical shutter 14 </ b> X, and the reflected light 18 is absorbed by the laser absorption block 22. Thereby, compared with the case where a chopper disk is used, the amount of laser light absorbed by the shutter 14X can be greatly reduced, and a high-power laser can be used for the laser oscillator.

  Further, since the through path 27, which is the optical path of the laser beam, is formed offset from the center line of the shutter 14X, there is almost no amount of light reflected from the input laser 12 and returning to the light source section side, which causes damage to the laser oscillator. It becomes possible to prevent. In particular, when a fiber laser is used for the laser oscillator 2, it is effective because it is easily affected by reflected waves.

A wide range of ON / OFF control is possible by the combination of the CW gate signal ON61 or the pulsed laser gate signal ON61a, the shape of the apertures 15X and 36, and the control of the control device and the rack and pinion gear. Thereby, a burst wave having an arbitrary pulse width and pulse interval can be obtained, and for example, the workpiece can be processed with a fine pattern such as a dotted line or a broken line.
In particular, as shown in FIG. 8, by adopting a burst mode in which burst waves 69a and 70a in which a high-frequency pulse train is repeated at a low-frequency cycle are irradiated to a workpiece, machining with very little influence of heat is performed. Is possible.

  Moreover, for example, when pattern processing is performed on the surface of the metal that is the workpiece by the burst wave obtained by the laser processing apparatus of the present embodiment, it is possible to form fine grooves on the surface of the metal. Become. And adhesiveness of a metal and another material through an adhesive agent can be improved by an adhesive agent entering this groove | channel.

<3. Modification of Second Embodiment>
(Modification 1)
Here, as a modification of the second embodiment, cross-sectional views of the shutter of the first shutter unit are shown in FIGS. 9A and 9B.

The modification shown in FIGS. 9A and 9B is a case where a thin cylindrical shutter 14Y is used for the first shutter unit.
The cylindrical shutter 14Y has four apertures 15Y formed at equal intervals, and the surface thereof is a reflecting material 19. The inside of the cylindrical shutter 14Y is a cavity.
Other configurations are the same as those of the second embodiment shown in FIGS. 6A and 6B.

  In this example, since four apertures 15Y are formed at equal intervals on the cylindrical shutter 14Y, four pulses or four pulse groups are obtained during one rotation of the cylindrical shutter 14Y.

  Even when the cylindrical shutter 14Y of this modification is employed, the same effect as that obtained when the shutter 14X of the second embodiment is employed.

  In order to manufacture this cylindrical shutter 14Y, for example, after forming a thin plate into a cylindrical shape, the aperture 15Y is formed, the disc is welded to both ends of the cylinder, and the shaft 21Y is attached to the center of the disc. good.

(Modification 2)
As another modification example of the second embodiment, cross-sectional views of the shutter of the first shutter unit are shown in FIGS. 10A and 10B.

The modification shown in FIGS. 10A and 10B is a case where a cylindrical shutter 14Z having a larger aperture than the other examples is used for the first shutter unit.
The cylindrical shutter 14Z has four apertures 15Z formed at equal intervals, and the surface thereof is a reflecting material 19Z. The inside of the cylindrical shutter 14Z is filled in a columnar shape so that the center portion has a certain thickness around the shaft 21Z, and a space is formed between the columnar portion and the surface cylindrical portion. And it rotates around the shaft 21Z as shown by the arrow 20Z.
The aperture 15Z is formed larger than the aperture 15X in FIG. 6 and the aperture 15Y in FIG. 9 and is sufficiently larger than the light flux of the input laser 12.
Further, the laser absorption block 22Z of this example is formed to be slightly larger than the laser absorption block 22 of other examples.
Other configurations are the same as those of the second embodiment shown in FIGS. 6A and 6B.

  In this example, since four apertures 15Z are formed at equal intervals on the cylindrical shutter 14Z, four pulses or four pulse groups are obtained during one rotation of the cylindrical shutter 14Z.

  Even when the cylindrical shutter 14Z of this modification is employed, the same effect as that obtained when the shutter 14X of the second embodiment is employed can be obtained.

<4. Third Embodiment>
FIG. 11 shows a schematic configuration diagram (perspective view) of a laser processing apparatus according to the third embodiment of the present invention.
In the present embodiment, in the laser processing apparatus 81 shown in FIG. 11, the first shutter unit 11a and the second shutter unit 31a are configured differently from the laser processing apparatus 1 of the first embodiment.
The light source unit and the processing unit have the same configuration as the laser processing apparatus 1 of the first embodiment shown in FIG.

The first shutter unit 11a of the laser processing apparatus 81 of the present embodiment uses a hemispherical shutter 14a. In addition, the first shutter unit 11a includes a laser absorption block 22a provided diagonally to the left of the hemispherical shutter 14a.
The hemispherical shutter 14a has a hemispherical outer shape, and an aperture 15a through which laser light passes is provided on a spherical surface thereof (a portion not including a plane at the end of the hemisphere), and can be rotated around a central axis 21a. It is configured.
The hemispherical shutter 14a is connected to a spindle motor 24 that rotates the hemispherical shutter 14a.
In the first shutter unit 11a, the spindle motor 24, the air bearing 23, the coupler 25, and the interface 26 have the same configuration as that of the laser processing apparatus 1 of the first embodiment.

The surface of the hemispherical shutter 14a is formed of a reflective material 19a. The hemispherical shutter 14a is driven to rotate about a shaft 21a by a spindle motor 24 as indicated by an arrow 20.
Several apertures 15a are formed on the spherical surface of the hemispherical shutter 14a, and laser light can pass between these apertures 15a.
The size of the aperture 15a is slightly larger than the luminous flux of the laser beam passing therethrough.
The aperture 15a is formed so that the optical path of the laser beam passing through the aperture 15a passes through the center line of the hemispherical shutter 14a.
The light source portion and the hemispherical shutter 14a are arranged relative to each other so that the laser light passes when the hemispherical shutter 14a rotates and two of the several apertures 15a move up and down. The position where the input laser 12a hits the hemispherical shutter 14a is directly above the center line of the hemispherical shutter 14a.

  The shaft 21a serving as the rotation shaft is configured to partially penetrate the hemispherical shutter 14a or to be attached to the surface by welding, bonding or caulking, and the laser beam penetrates the hemispherical shutter 14a without an obstacle. It becomes.

Due to the rotation of the hemispherical shutter 14a, the position of the hemispherical shutter 14a to which the input laser 12a hits changes such as the aperture 15a or a portion other than the aperture 15a.
When the input laser 12a hits the aperture 15a, it passes through the aperture 15a, is emitted from the lower aperture 15a, and becomes the output laser 13a.
When the input laser 12a hits a portion other than the aperture 15a, the input laser 12a is reflected by the reflecting material 19a on the surface of the hemispherical shutter 14a. At this time, since the input laser 12a is irradiated to a portion that is not the uppermost portion of the curved surface of the hemispherical shutter 14a, the input laser 12a reflected by the reflecting material 19a does not return to the incident side (directly above), It is absorbed by the laser absorption block 22a toward the laser absorption block 22a.

The hemispherical shutter 14a can be formed of, for example, metal, ceramic, graphite, synthetic resin, or the like.
Alternatively, a material having high reflectivity may be used for the hemispherical shutter 14a, and the material may be used as it is, or a material having low reflectivity may be used for the hemispherical shutter 14a, and the surface may be reflected by a material having high reflectivity. A film may be formed as the reflective material 19a.
The inside of the hemispherical shutter 14a is hollow. The hemispherical shutter 14a is preferably reduced in weight in order to cope with high-speed rotation, and it is desirable to devise a balance in order to improve rotation accuracy.

Furthermore, in order to prevent irregular reflection of laser light on the inner surface of the hemispherical shutter 14a, it is desirable that an absorbing material that absorbs laser light is formed on the inner surface of the hemispherical shutter 14a.
When a material having a high reflectance is used for the hemispherical shutter 14a, an absorbent material is coated on the inner surface of the hemispherical shutter 14a.
When an absorbing material is used for the hemispherical shutter 14a, the inner surface is left as it is.
Further, the material of the hemispherical shutter 14a is not high in reflectivity or absorptivity, but a light and strong material may be used to form a reflective film on the surface and coat the inner surface with an absorbent material.

The laser absorption block 22a is provided with a cooler such as air cooling, water cooling, or a Peltier element according to the intensity of the laser energy.
Further, the laser absorption block 22a may be configured to also serve as a laser power meter sensor.

  The second shutter unit 31a of the laser processing apparatus 61 of the present embodiment is provided with three types of apertures 35a, 36a, and 37a through which laser light passes, and is configured to be rotatable around a central shaft 41a. A cylindrical shutter 34a, a spindle motor 44 for rotating the cylindrical shutter 34a, and a rack and pinion gear 48 for moving the cylindrical shutter 34a and the spindle motor 44 in the horizontal direction in the figure are provided. Further, a laser absorption block 42a provided obliquely above the cylindrical shutter 34a is provided.

The cylindrical shutter 34a has a cylindrical shape with a cylindrical outer shape and a hollow inside, and the surface is formed of a reflective material 39a. The cylindrical shutter 34 a is provided with a shaft 41 a that passes through the center line of the outer shape, and is driven to rotate about the shaft 41 a as indicated by an arrow 40 by a spindle motor 44.
Of the second shutter unit 31a, the spindle motor 44, the air bearing 43, the coupler 45, the interface 46, and the rack and pinion gear 48 have the same configurations as those of the laser processing apparatus 1 of the first embodiment. is there.

The cylindrical shutter 34a is formed with three types of apertures 35a, 36a, and 37a having different opening sizes and shapes, and laser light can pass between the apertures 35a, 36a, and 37a.
Among these, the central aperture 36a of the cylindrical shutter 34a has the same configuration as the left aperture 35 of the cylindrical shutter 34 of the first embodiment. The right aperture 37a of the cylindrical shutter 34a has the same configuration as the right aperture 37 of the cylindrical shutter 34 of the first embodiment.
The left aperture 35a of the cylindrical shutter 34a is formed at equal intervals in several places.
Each aperture 35a, 36a, 37a is formed such that the optical path of the laser beam passing therethrough is offset from the center line of the cylindrical shutter 34a. The position where the input laser 32a hits the cylindrical shutter 34 is offset from directly above the center line of the cylindrical shutter 34a corresponding to the positions of the apertures 35a, 36a, and 37a.

The output laser 13a emitted from the hemispherical shutter 14a of the first shutter unit 11a is input to the cylindrical shutter 34a of the second shutter unit 31a as the input laser 32a.
By the rotation of the cylindrical shutter 34a, the position of the cylindrical shutter 34a to which the input laser 32a hits changes such as the apertures 35a, 36a, and 37a, or portions other than the apertures 35a, 36a, and 37a.
When the input laser 32a hits the apertures 35a, 36a, 37a, it passes through the apertures 35a, 36a, 37a and is emitted from the lower apertures 35a, 36a, 37a to become the output laser 33a.
When the input laser 32a hits a portion other than the apertures 35a, 36a, 37a, the input laser 32a is reflected by the reflecting material 39a on the surface of the cylindrical shutter 34a. At this time, since the input laser 32a is irradiated to a position offset from directly above the center line of the cylindrical shutter 34a, the input laser 32a reflected by the reflecting material 39a does not return to the incident side, and the laser absorption block It goes to 42a and is absorbed by the laser absorption block 42a.

The cylindrical shutter 34a can be formed of, for example, metal, ceramic, graphite, synthetic resin, or the like.
Further, the material of the cylindrical shutter 34a, the configuration of the reflecting material 39a, and the absorber can be the same as those of the cylindrical shutter 34 of the first embodiment.

When the laser energy is strong, the laser absorption block 42a is provided with a cooler such as air cooling, water cooling, or Peltier element.
Further, the laser absorption block 42a may be configured to also serve as a sensor for the laser power meter. In such a configuration, the laser power can be measured at a place where the laser is constantly reflected.

Further, the second shutter unit 31 a can move the cylindrical shutter 34 a and the spindle motor 44 in the horizontal direction in the drawing as indicated by an arrow 49 by the rack and pinion gear 48. Thereby, the aperture through which the input laser 32a passes can be switched between the three types of apertures 35a, 36a, and 37a.
The left aperture 35a and the central aperture 36a are formed to be slightly larger than the luminous flux of the laser beam passing therethrough.
The right side aperture 37a is formed in a fan shape whose opening width becomes narrower toward the left side. With this configuration, the position of the input laser 32a hitting the aperture 37a is changed by the operation of the rack and pinion gear 48, thereby changing the aperture width of the aperture 37a with respect to the input laser 32a and changing the generation timing of the burst wave laser. Is possible. By continuously operating the rack and pinion gear 48, it is possible to continuously change the generation timing of the burst wave laser.
In FIG. 11, there is an aperture 36a in the center of the cylindrical shutter 34a at a position through which the input laser 32a passes, and the input laser 32a passes through the aperture 36a and is emitted from the lower aperture 36a to become an output laser 33a. ing.

The output laser 33 emitted from the cylindrical shutter 34a of the second shutter unit 31a is focused by the optical system unit 50 to become a condensing laser 51, which forms an image on the workpiece 52 and is irradiated. The workpiece 52 is processed.
Then, the position where the workpiece 52 is processed is changed by moving the XY table 53 on which the workpiece 52 is placed in the X-axis direction (arrow 54) or the Y-axis direction (arrow 55). Can do.

  In the first shutter unit 11a and the second shutter unit 31a, the hemispherical shutter 14a and the cylindrical shutter 34a are rotationally driven to change the positions of the apertures 15a, 35a, 36a, and 37a, thereby turning on / off the laser beam. OFF-controlled. Thereby, the condensing laser 51 irradiated to the workpiece 52 can be a burst wave laser.

  By combining the operations of the hemispherical shutter 14a and the cylindrical shutter 34a, the operation of the optical system unit 50, and the operation of the XY table 53 in the X-axis direction 54 and the Y-axis direction 55, a laser is applied onto the workpiece 52. By scanning the beam, it is possible to obtain a laser processing result 56 that combines continuous lines or dotted lines or broken lines.

In the present embodiment, FIG. 12A shows a cross-sectional view of the hemispherical shutter 14a of the first shutter unit 11a, and FIG. 12B shows a state where the laser light is blocked by the first shutter unit 11a. In FIG. 12B, the second shutter unit 31a is not shown.
As shown in FIG. 12A, the input laser 12a hitting the aperture 15a on the hemispherical shutter 14a passes through the center of the circle in the cross section of the hemispherical shutter 14a, and is emitted from the lower aperture 15a to be output. The laser 13a is obtained.
As shown in FIG. 12B, the input laser 12a impinging on the reflecting material 19a on the surface of the hemispherical shutter 14a is reflected by the reflecting material 19a to become reflected light 18a directed diagonally upward to the left, and is absorbed by the laser absorption block 22a. .

  In the present embodiment, ON / OFF control of laser light can be performed by the same method as in the previous embodiments shown in FIGS. 4 to 5 and 7 to 8.

In FIG. 12A, ten apertures 15a are formed at equal intervals in the hemispherical shutter 14a.
Thus, 10 pulse waves or 10 pulse groups are obtained as the output laser 13a while the hemispherical shutter 14a rotates once.

As shown in FIG. 12A, when the number of apertures 15a of the hemispherical shutter 14a of the first shutter unit 11a is 10 and the rotational speed of the hemispherical shutter 14a is 200,000 rpm, 3.3 kHz A high repetition frequency of x10 = 33 kHz is obtained.
For example, there are spindle motors with high-frequency and air bearings manufactured by ABL of the United Kingdom and Westwind air spindles, which can achieve 300,000 revolutions per minute without load. Has been.
In addition, for example, in a high-speed spindle motor of 50,000 revolutions per minute that is easily available, the speed is 833 revolutions per second, which is 0.833 kHz. For example, as shown in FIG. 12A, when a hemispherical shutter 14a is applied and ten apertures 15a are provided, a repetition frequency of 8.3 kHz is obtained.

  According to the configuration of the laser processing apparatus 81 of the above-described embodiment, the surfaces are the reflecting materials 19a and 39a, the apertures 15a, 35a, 36a, and 37a through which the laser light passes are formed, and the axis passing through the center line is formed. A hemispherical shutter 14a and a cylindrical shutter 34a that rotate around are provided between the light source section and the processing section. Therefore, by rotating the hemispherical shutter 14a and the cylindrical shutter 34a, the laser beam passes through the apertures 15a, 35a, 36a, and 37a, and the laser beam is reflected by the reflectors 19a and 39a and blocked. And can be switched. If at least one of the two shutters 14a and 34a is rotated at a high speed, the laser light can be switched ON / OFF at a high speed.

Further, the hemispherical shutter 14a and the cylindrical shutter 34a are rotating bodies centered on the shafts 21a and 41a, have a solid three-dimensional structure, and rotate around the shafts 21a and 41a. Less susceptible to air resistance. Thereby, even if it rotates at high speed, it can be rotated stably.
Further, when blocking the laser light, the laser light is reflected by the reflecting materials 19a and 39a on the surfaces of the respective shutters 14a and 34a, and the reflected light is absorbed by the laser absorption blocks 22a and 42a. As a result, the amount of laser light absorbed by the respective shutters 14 a and 34 a can be greatly reduced as compared with the chopper disk, and a high-power laser can be used for the laser oscillator 2.

  Further, since the input laser 12a is applied to a spherical surface that is not a flat surface at the end of the hemispherical shutter 14a, the input laser 12a is hardly reflected and returned to the light source unit side, thereby preventing damage to the laser oscillator 2. It becomes possible to do. In particular, when a fiber laser is used for the laser oscillator 2, it is effective because it is easily affected by reflected waves.

  A wide range of ON / OFF control is possible by combining the ON state of the gate signal, the shape of the apertures 15a, 35a, 36a, and 37a, and the control of the control device 57 and the rack and pinion gear 48. Thereby, a burst wave having an arbitrary pulse width and pulse interval can be obtained, and for example, the workpiece 52 can be processed with a fine pattern such as a dotted line or a broken line.

  In addition, for example, when pattern processing is performed on the surface of the metal that is the workpiece 52 by the burst wave obtained by the laser processing apparatus 81 of the present embodiment, fine grooves may be formed on the surface of the metal. It becomes possible. And adhesiveness of a metal and another material through an adhesive agent can be improved by an adhesive agent entering this groove | channel.

  In the third embodiment described above, the hemispherical shutter 14a is used. However, a spherical shutter can be used instead of the hemispherical shutter 14a. However, when using a spherical shutter, the reflected light returns to the light source side when the input laser hits the surface of the spherical shutter, so it is desirable to arrange the input laser so that it does not hit the surface of the spherical shutter. . For this purpose, the optical path of the laser light passing through the aperture may be offset so as not to pass through the center of the spherical shutter.

<5. Fourth Embodiment>
A schematic configuration diagram (perspective view) of a laser processing apparatus according to the fourth embodiment of the present invention is shown in FIGS. 13A and 13B.
In the present embodiment, a conical shutter 14b shown in FIGS. 13A and 13B is used as the shutter of the shutter unit. FIG. 13A shows a case where laser light passes through the conical shutter 14b. FIG. 13B shows a case where the laser light is blocked by the conical shutter 14b.
The light source unit and the processing unit have the same configuration as the laser processing apparatus 1 of the first embodiment shown in FIG.

The conical shutter 14b of the present embodiment has a conical outer shape with an aperture 15b that allows laser light to pass through the side surface, and is configured to be rotatable around an axis 21b that passes through the center line.
The surface of the conical shutter 14b is formed of a reflective material 19b. The conical shutter 14b is driven to rotate about a shaft 21b as shown by an arrow 20b by a spindle motor (not shown).
The conical shutter 14b has four apertures 15b including those not shown in the curved surface, and the laser beam can pass between these apertures 15b.
The size of the aperture 15b is a little larger than the luminous flux of the laser beam that passes therethrough.
The aperture 15b is formed so that the optical path of the laser beam passing therethrough passes through the center line of the conical shutter 14b.
The light source unit and the conical shutter 14b are arranged relative to each other so that laser light passes when the conical shutter 14b rotates and two of the four apertures 15b move up and down. The position where the input laser 12b hits the conical shutter 14b is directly above the center line of the conical shutter 14b.

  The shaft 21b serving as the rotation shaft is configured to partially penetrate the conical shutter 14b or to be attached to the surface by welding, bonding, caulking, or the like, and the laser light penetrates the inside of the conical shutter 14b without an obstacle. It becomes.

Due to the rotation of the conical shutter 14b, the position of the conical shutter 14b on which the input laser 12b hits changes such as the aperture 15b or a portion other than the aperture 15b.
When the input laser 12b hits the aperture 15b, it passes through the aperture 15b, is emitted from the lower aperture 15b, and becomes the output laser 13b.
When the input laser 12b hits a portion other than the aperture 15b, the input laser 12b is reflected by the reflecting material 19b on the surface of the conical shutter 14b. At this time, since the input laser 12b is irradiated onto the curved surface of the conical shutter 14b, the input laser 12b reflected by the reflecting material 19b does not return to the incident side (directly above), as shown in FIG. 13B. The reflected light 18b travels toward the laser absorption block 22b, and is absorbed by the laser absorption block 22b.

The conical shutter 14b can be formed of, for example, metal, ceramic, graphite, synthetic resin, or the like.
The material of the conical shutter 14b, the configuration of the reflecting material and the absorbing material, and the configuration for cooling the laser absorption block 22b can be the same as those in the above-described embodiments.

  The conical shutter 14b is rotationally driven and the position of the aperture 15b is changed, so that the laser light is ON / OFF controlled. Thereby, the condensing laser 51 irradiated to the workpiece 52 can be a burst wave laser.

  As shown in FIG. 13A, the conical shutter 14b of the present embodiment may constitute the shutter of the shutter unit alone, but the second shutter unit of each embodiment shown in FIG. 1 and FIG. You may combine the cylindrical shutters 34 and 34a of 31 and 31a.

  According to the configuration of the laser processing apparatus of the present embodiment described above, the surface is the reflecting material 19b, the aperture 15b through which the laser light passes is formed, and the conical shutter rotates around the axis 21b passing through the center line. 14b is provided between the light source unit and the processing unit. Therefore, by rotating the conical shutter 14b, it is possible to switch between a state in which the laser light passes through the aperture 15b and a state in which the laser light is reflected and blocked by the reflecting material 19b. If the conical shutter 14b is rotated at a high speed, the laser light can be switched ON / OFF at a high speed.

Further, the conical shutter 14b is a rotating body centered on the shaft 21b, has a solid three-dimensional structure, and rotates around the shaft 21b, so that it is not easily affected by air resistance during rotation. Thereby, even if it rotates at high speed, it can be rotated stably.
Further, when blocking the laser light, the laser light is reflected by the reflecting material 19b on the surface of the conical shutter 14b, and the reflected light 18b is absorbed by the laser absorption block 22b. As a result, the amount of laser light absorbed by the conical shutter 14b can be significantly reduced as compared with the chopper disk, and a high-power laser can be used for the laser oscillator.

  Further, since the input laser 12b is applied to the side surface of the conical shutter 14b, the input laser 12b does not hit the reflector 19b vertically when hitting the reflector 19b, so that it hardly reflects and returns to the light source side. It becomes possible to prevent damage to the laser oscillator. In particular, when a fiber laser is used as a laser oscillator, it is effective because it is easily affected by reflected waves.

  A wide range of ON / OFF control is possible by combining the ON state of the gate signal, the shape of the aperture 15b, and the control of the control device and the rack and pinion gear.

  Also, for example, when pattern processing is performed on the surface of the metal that is the workpiece by the burst wave obtained by the laser processing apparatus of the present embodiment, a fine groove is formed on the surface of the metal, and the adhesive It is possible to improve the adhesion between the metal and other materials via the.

<6. Fifth embodiment>
14A and 14B are schematic configuration diagrams (perspective views) of a laser processing apparatus according to the fifth embodiment of the present invention.
In the present embodiment, the polygonal pyramid shutter 14c shown in FIGS. 14A and 14B is used as the shutter of the shutter unit. FIG. 14A shows a case where laser light passes through the polygonal pyramid shutter 14c. FIG. 14B shows a case where the laser light is blocked by the polygonal pyramid shutter 14c.
The light source unit and the processing unit have the same configuration as the laser processing apparatus 1 of the first embodiment shown in FIG.

The polygonal pyramid-shaped shutter 14c of the present embodiment has a polygonal pyramid-shaped outer shape and an aperture 15c that allows laser light to pass through the side surface, and is configured to be rotatable around an axis 21c that passes through the center line.
The surface of the polygonal pyramid-shaped shutter 14c is formed of a reflective material 19c. The polygonal pyramid-shaped shutter 14c is rotationally driven about a shaft 21c as shown by an arrow 20c by a spindle motor (not shown).
14A and 14B, the polygonal pyramid-shaped shutter 14c has a hexagonal pyramidal shape, and the polygonal-pyramidal shutter 14c has two apertures 15c formed at the center of the side boundary ridge. The laser beam can pass between the apertures 15c.
The size of the aperture 15c is a little larger than the luminous flux of the laser beam that passes therethrough.
The aperture 15c is formed so that the optical path of the laser beam passing therethrough passes through the center line of the polygonal pyramid shutter 14c.
The light source section and the polygonal pyramid shutter 14c are arranged relative to each other so that the laser beam passes when the polygonal pyramid shutter 14c rotates and the two apertures 15c move up and down. The position where the input laser 12c hits the polygonal pyramid shutter 14c is directly above the center line of the polygonal pyramid shutter 14c.

  14A and 14B, the polygonal pyramid shutter 14c has a hexagonal pyramid shape. However, the polygonal pyramid shutter is not limited to a hexagonal pyramid shape, and an arbitrary polygonal pyramid shape greater than or equal to a triangular pyramid may be employed. Is possible. More preferably, in consideration of the spread of reflected light, the ease of producing a polygonal pyramid shape, etc., one of a quadrangular pyramid shape, a hexagonal pyramid shape, and an octagonal pyramid shape is used.

  The axis 21c serving as the rotation axis is configured to partially penetrate the polygonal pyramid shutter 14c or to be attached to the surface by welding, bonding, or caulking, and the laser beam penetrates the inside of the polygonal cone shutter 14c without an obstacle. It becomes the composition to do.

Due to the rotation of the polygonal pyramid shutter 14c, the position of the polygonal pyramid shutter 14c to which the input laser 12c hits changes such as the aperture 15c or a portion other than the aperture 15c.
When the input laser 12c hits the aperture 15c, it passes through the aperture 15c, is emitted from the lower aperture 15c, and becomes the output laser 13c.
When the input laser 12c hits a portion other than the aperture 15c, the input laser 12c is reflected by the reflecting material 19c on the surface of the polygonal pyramid shutter 14c. At this time, since the input laser 12c is irradiated on the side surface of the polygonal pyramid-shaped shutter 14c or near the edge of the boundary of the side surface, the input laser 12c reflected by the reflecting material 19c does not return to the incident side (directly above) As shown in FIG. 14B, the reflected light 18c travels toward the upper left laser absorption block 22c and is absorbed by the laser absorption block 22c.

The polygonal pyramid shutter 14c can be formed of, for example, metal, ceramic, graphite, synthetic resin, or the like.
Further, the material of the polygonal pyramid shutter 14c, the configuration of the reflection material and the absorption material, and the configuration for cooling the laser absorption block 22c can be the same as the configuration of each of the embodiments described above.

  The polygonal pyramid-shaped shutter 14c is rotationally driven, and the position of the aperture 15c is changed, whereby the laser light is ON / OFF controlled. Thereby, the condensing laser 51 irradiated to the workpiece 52 can be a burst wave laser.

  As shown in FIG. 14A, the polygonal pyramid-shaped shutter 14c of the present embodiment may constitute a shutter of the shutter unit alone, but the second shutter of each embodiment shown in FIG. 1 and FIG. The cylindrical shutters 34 and 34a of the units 31 and 31a may be combined.

  According to the configuration of the laser processing apparatus of the present embodiment described above, the surface is the reflecting material 19c, the aperture 15c through which the laser light passes is formed, and the polygonal pyramid rotates around the axis 21c passing through the center line. A shutter 14c is provided between the light source unit and the processing unit. Therefore, by rotating the polygonal pyramid shutter 14c, it is possible to switch between a state in which the laser light passes through the aperture 15c and a state in which the laser light is reflected and blocked by the reflecting material 19c. If the polygonal pyramid shutter 14c is rotated at a high speed, the laser light can be switched ON / OFF at a high speed.

In addition, the polygonal pyramid shutter 14c has a solid three-dimensional structure, and has a hexagonal pyramid shape close to a conical shape that is a rotating body, and is rotated about the shaft 21c. Therefore, the influence of air resistance during rotation is reduced. It is hard to receive. Thereby, even if it rotates at high speed, it can be rotated stably.
Further, when blocking the laser light, the laser light is reflected by the reflective material 19c on the surface of the polygonal pyramid shutter 14c, and the reflected light 18c is absorbed by the laser absorption block 22c. As a result, the amount of laser light absorbed by the polygonal pyramid-shaped shutter 14c can be significantly reduced as compared with the chopper disk, and a high-power laser can be used for the laser oscillator.

  Further, since the input laser 12c is irradiated on the side surface of the multi-conical shutter 14c and the edge of the boundary thereof, the input laser 12c does not hit perpendicularly when it hits the reflecting material 19c. It is possible to prevent the laser oscillator from being damaged. In particular, when a fiber laser is used as a laser oscillator, it is effective because it is easily affected by reflected waves.

  A wide range of ON / OFF control is possible by combining the ON state of the gate signal, the shape of the aperture 15c, and the control of the control device and the rack and pinion gear.

  Also, for example, when pattern processing is performed on the surface of the metal that is the workpiece by the burst wave obtained by the laser processing apparatus of the present embodiment, a fine groove is formed on the surface of the metal, and the adhesive It is possible to improve the adhesion between the metal and other materials via the.

In the above-described embodiments, the reflected light reflected by the reflecting material is absorbed by the laser absorption block. The laser absorption block is configured to be slightly larger than the range in which the reflected light spreads.
In the present invention, the laser absorber that absorbs reflected light is not limited to a block shape, and other configurations such as a plate shape are possible. Further, the range in which the laser absorber is provided can be set to an arbitrary range as long as it does not hinder the rotational drive around the shutter axis and the optical paths of the input laser and the output laser. For example, a configuration in which openings are provided in the optical path portions of the input laser and the output laser around the shutter is also possible.

In each of the above-described embodiments, the direction of the axis of rotation of the shutter (center line of the shutter) and the direction of the optical path of the laser light passing through the shutter are perpendicular.
The present invention is not limited to a configuration in which these directions are vertical, and for example, a configuration in which an angle formed by these two directions is smaller than 90 ° may be employed. The permissible range of the angle formed depends on the configuration of the shutter, but is a range of 90 ° to 45 °, for example. In the case of this configuration, the aperture of the shutter and the laser absorption block may be formed at appropriate positions according to the optical path of the laser beam.
In the case of a conventional chopper disk, the configuration is different from the present invention because the direction of the rotation axis of the disk and the direction of the optical path of the laser beam passing therethrough are parallel or nearly parallel.
As in the above-described embodiments, when the direction of the axis of rotation of the shutter is perpendicular to the direction of the optical path of the laser light, there is an advantage that the design of the laser processing apparatus and the arrangement of each part are facilitated.

  In each of the first to third embodiments, the two shutter units are provided. However, it is also possible to configure the shutter unit with only one of the two shutter units of each embodiment.

In the present invention, the duty ratio of the laser light pulse output from the shutter is determined by the interval between the apertures of the shutter.
This point also applies to the configuration of each of the above-described embodiments. However, when there are a plurality of shutters as in the configurations of FIGS. 1 and 11, the interval of the aperture of the shutter that mainly defines the pulse width is used. The duty ratio is determined.

The present invention is not limited to the above-described embodiment, and various other configurations can be taken without departing from the gist of the present invention.
In addition, the configuration of each embodiment can be appropriately modified or combined within the scope of the present invention. For example, the through path employed in the shutter 14X of the second embodiment can be applied to shutters of other shapes (hemispherical, spherical, conical, polygonal pyramid).

1,81 laser processing apparatus, 2 laser oscillator, 3 collimated laser beam, 4 beam expander, 11, 11a first shutter unit, 12, 12a, 12b, 12c, 32, 32a input laser, 13, 13a, 13b , 13c, 33, 33a Output laser, 14, 14Y, 14Z, 34, 34a Cylindrical shutter, 14X shutter, 14a Hemispherical shutter, 14b Conical shutter, 14c Polygonal cone shutter, 15, 15X, 15Y, 15Z, 15a , 15b, 15c, 35, 35a, 36, 36a, 37, 37a Aperture, 18, 18Z, 18a, 18b, 18c, 38, 38a Reflected light, 19, 19Z, 19a, 19b, 19c, 39, 39a Reflector, 20, 20Z, 20a, 20b, 20c 40 rotations, 21, 21Y, 21Z, 21a, 21b, 21c, 41, 41a shaft, 22, 22Z, 22a, 22b, 22c, 42, 42a laser absorption block, 23, 43 air bearing, 24, 44 spindle motor, 25, 45 coupler, 26, 46 interface, 27 through path, 31, 31a second shutter unit, 48 rack and pinion gear, 50 optical system unit, 51 condensing laser, 52 workpiece, 53 XY table, 54 X-axis direction, 55 Y-axis direction, 56 Laser processing result, 57 Control device, 60, 60a Gate signal OFF, 61, 61a Gate signal ON, 62 CW laser OFF, 62a Pulse wave laser OFF, 63 CW laser ON, 63a Pulse wave laser ON, 65 69 CW burst wave, 65a, 67, 67a, 69a, 70, 70a burst wave, 71, 72, 73 enlarged waveform

Claims (5)

It has a cylindrical or spherical outer shape and can be driven to rotate around an axis passing through the center line of the outer shape.
A plurality of apertures are provided on the cylindrical side surface or the spherical spherical surface for allowing laser light to pass through the inside.
The plurality of apertures are formed such that an optical path of laser light passing between two of the plurality of apertures is offset from the center line of the cylindrical shape or the center of the spherical shape. ,
In the side surface or the spherical surface, the surface other than the aperture is a reflector,
A laser shutter comprising a laser absorber that absorbs laser light reflected by the reflecting material. It has a hemispherical shape, a conical shape, or a polygonal pyramid shape, and can be driven to rotate around an axis passing through the center line of the outer shape.
A plurality of apertures for allowing laser light to pass therethrough are provided on the spherical surface of the hemisphere or on the side surface of the conical shape or the polygonal pyramid shape,
In the spherical surface or the side surface, the surface other than the aperture is a reflector,
A laser shutter comprising a laser absorber that absorbs laser light reflected by the reflecting material.   The laser shutter according to claim 1, wherein the cylindrical shape has a cylindrical shape with a space, and the cylindrical inner wall is made of an absorbing material that absorbs the laser light.   The laser shutter according to claim 1 or 2, wherein a material filled in the outer shape is provided with a through path that passes between the two apertures. A light source unit including a laser oscillator as a light source;
A shutter unit having one or more laser shutters for switching between passing and blocking with respect to the laser light from the light source unit;
Irradiating the workpiece with laser light that has passed through the shutter unit, and processing the workpiece, comprising a processing unit,
Each laser shutter of the shutter unit has the configuration of the laser shutter according to any one of claims 1 to 4. A laser processing apparatus.

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