JP3070892B2 - Variable shape mirror, adaptive optics device, astronomical telescope, laser isotope separation device, and laser processing machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a deformable mirror of an adaptive optics device for correcting an optical distortion of a laser beam or other light, and more particularly to a high-density actuator for a deformable mirror. Improving maintainability.

[0002]

2. Description of the Related Art An adaptive optics apparatus detects optical distortion and corrects the distortion with a deformable mirror. For this reason, the deformable mirror is required to have a high speed capable of coping with a temporal change of an optical distortion to be corrected and a high density of an actuator capable of coping with a spatial change. Regarding the structure of the deformable mirror, for example, US Pat. Nos. 3,904,274 and 42026.
No. 05, No. 4239343, No. 4248504 and the like.

[0003]

However, the above prior art does not consider the improvement of the maintainability such as the high density of the actuator of the deformable mirror and the replacement of the actuator when the actuator or the like is damaged.

An object of the present invention is to provide actuators for solving the above problems of the deformable mirror, the adaptive optical device using the variable shape mirror, to improve performance by applying the adaptive optical device It is an object of the present invention to provide a laser oscillator, a laser processing machine, a laser isotope separation device, an astronomical telescope, other optical devices, and the like, which can be used.

[0005]

The above object is achieved as follows. That is, a plurality of stacked piezoelectric elements are arranged one-dimensionally or two-dimensionally on a flat plate, and then mounted on a mirror by using a plurality of piezoelectric element arrays in which the space between and around the stacked piezoelectric elements is covered with an insulating material. You. This structure can increase the mounting density because the covering portion can be shared. In addition, each of the piezoelectric element arrays is detachably attached to the lens barrel. This mechanism is easier in terms of space than the mechanism for each piezoelectric element, and can achieve higher density. Further, the connection between the piezoelectric element array and the mirror is connected using a magnet or an adhesive whose adhesive force changes depending on the temperature. Thereby, workability at the time of replacement is facilitated.

[0006]

The basic structure of a deformable mirror is a mirror that reflects light.
A plurality of two-dimensionally attached actuators for changing the unevenness are provided on the surface. As an actuator,
A laminated piezoelectric element in which a plurality of piezoelectric elements displaced in proportion to an applied voltage are stacked and each of which is electrically connected in parallel is used, and is excellent in responsiveness. The laminated piezoelectric element is covered with an insulating material between the laminated piezoelectric element and the electrode, so that dielectric breakdown can be prevented. In the multilayer piezoelectric element, the mounting density can be increased by reducing the cross-sectional area of the element itself and reducing the thickness of the above-mentioned covering portion. Further, the configuration of the deformable mirror is a mechanism in which the laminated piezoelectric element and the mirror can be easily removed, thereby improving maintainability.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the deformable mirror according to the present invention will be described with reference to FIGS. 1A and 1B show a structure of a deformable mirror according to an embodiment of the present invention, wherein FIG. 1A is a top view and FIG. 1B is a side view. Reference numeral 6 denotes a piezoelectric element array having a structure in which a plurality of stacked piezoelectric elements 1 are arranged in a row on a pedestal flat plate, 9 denotes a pin mounted on the upper end of each stacked piezoelectric element 1, and 8 denotes a piezoelectric element array which is a lens barrel. A screw fixed to 7 is a plate, and 11 is a mirror attached to the pin 9. 2A and 2B show the structure of a piezoelectric element array according to one embodiment of the present invention, wherein FIG. 2A is a top view and FIG. 2B is a side view. In one stacked piezoelectric element, a plurality of piezoelectric elements are stacked, and each piezoelectric element is electrically connected in parallel to the external electrode 2. Each laminated piezoelectric element 1 is fixed to a pedestal 3 and the space between and around the elements 1 is filled and covered with an insulating material 4 to form an integrated structure. 5 is a lead wire derived from each external electrode 2.

First, the assembly structure of the piezoelectric element array shown in FIG. 2 will be described in detail. A plurality of the laminated piezoelectric elements 1 to which the external electrodes 2 and the lead wires 5 are mounted are mounted on the flat plate of the pedestal 3 in a row at equal intervals. After that, each laminated piezoelectric element 1
The space between and around is filled with an insulating material 4 and covered. With this configuration, the conventional laminated piezoelectric elements 1 each covered with an insulating material are individually mounted on a pedestal.
In the structure of the present invention, the insulating material 4 between the laminated piezoelectric elements 1 can be shared, so that the thickness can be reduced accordingly, and the mounting density of the laminated piezoelectric elements 1 on the pedestal 3 can be increased. The thickness of the coating layer of the insulating material 4 may be about 0.8 mm.

Next, an assembling structure of a deformable mirror using the above-described piezoelectric element array 6 will be described in detail with reference to FIG. A pin 9 for transmitting the displacement to the mirror 11 is attached to each laminated piezoelectric element 1 of the piezoelectric element array 6, screw holes are provided at both ends of the pedestal 3 of the piezoelectric element array 6, and the lens barrel 7 is screwed with a screw 8. Stop it. In this way, the plurality of piezoelectric element arrays 6 are screwed to the lens barrel 7 at regular intervals. At this time, the mounting interval d of each piezoelectric element array 6 is set to a value obtained by the following equation, assuming that the reflection angle of the deformable mirror is θ and the mounting interval of each laminated piezoelectric element 1 of the piezoelectric element array 6 is p. good. d = p / cos θ d: mounting interval of the piezoelectric element array 6 p: mounting interval of the laminated piezoelectric element 1 θ: reflection angle of the deformable mirror In this way, the laser beam or light wave to be corrected can be obtained. On the other hand, a deformable mirror that can be controlled with the same spatial resolution in both the x and y directions can be produced.

At the stage when all the piezoelectric element arrays 6 are mounted on the lens barrel 7, a plate 10 having holes formed therein is inserted in accordance with the arrangement of the pins 9. Then, all the pins 9 and the plate 10 are polished so as to have the same height from the reference plane. By providing such a plate 10, it is possible to perform polishing in which the heights of the respective pins 9 are made uniform, and it is possible to suppress variations in height caused during assembly due to the polishing. Preferably, the accuracy after assembly is on the order of 5μ.

After polishing the pins 9, the plate 10 is removed, and the pins 9 and the mirror 11 are connected with an adhesive. If the adhesive used at this time has an adhesive force that changes depending on the temperature, the mirror 11 can be relatively easily removed from the pin 9. That is, if a thermoplastic adhesive whose adhesive strength is reduced at 80 ° C. or higher is used, the pin 9 and the mirror 11 are usually connected with a strong adhesive at room temperature (20 ° C.), and the use of a deformable mirror Has no trouble,
When the piezoelectric element array 6 is damaged and needs to be replaced, the mirror 11 can be removed without applying unnecessary force to the other piezoelectric element arrays 6 by heating the adhesive to a temperature of 80 ° C. or higher.

In the above embodiment, the method of connecting the pin 9 and the mirror 11 with an adhesive whose adhesive force changes with temperature has been described. However, if one or both of the pin 9 and the mirror 11 are made of a material having a strong magnetic force, , Pin 9 and mirror 11 by magnetic force
Can be connected and detached by pulling them apart with a force greater than the magnetic force. In this way, the lens barrel 7 and the piezoelectric element array 6 and the piezoelectric element array 6 and the mirror 11 are configured to be detachable, so that the mirror 11 and the piezoelectric element array 6 can be easily replaced at the time of breakage, and the maintenance performance is high. A deformable mirror can be provided.

Next, a piezoelectric element array according to another embodiment of the present invention will be described with reference to FIG. 3A is a top view, and FIG. 3B is a side view, in which the laminated piezoelectric elements 1 are two-dimensionally arranged on the pedestal 3, and an insulating material 4 is provided between and around each laminated piezoelectric element 1. Fill and cover with. A lead wire 5 for driving each laminated piezoelectric element 1 passes through the pedestal 3, and a screw portion 12 provided for fixing a piezoelectric element array 61.
Pull out through the inside. With such a structure, the portion of the insulating material 4 can be narrowed, so that the multilayer piezoelectric element 1
The mounting density of the mounting structure can be increased.
Thus, the piezoelectric element array 61 can be attached.

FIG. 4 shows the piezoelectric element array 61 described with reference to FIG.
1 shows a cross-sectional structure of a deformable mirror constituted by using FIG. Each of the piezoelectric element arrays 61 is attached to the lens barrel 7 with the nut 13 using the screw portion 12. Other structures are the same as those of the embodiment of FIGS. In this way, by adopting a structure of a deformable mirror using a plurality of piezoelectric element arrays 61 in which the stacked piezoelectric elements 1 are two-dimensionally arranged, replacement of the mirror and the piezoelectric element when it is damaged becomes easy, and maintenance is easy. And a deformable mirror having a high height can be provided. Also, lead wire 5
Of the piezoelectric element array 61
The piezoelectric element array 6
The workability of assembling a deformable mirror made by arranging a plurality of 1s can be improved.

The piezoelectric element array and the deformable mirror according to one embodiment of the present invention have been described above. Next, an adaptive optical device according to another embodiment of the present invention and an application example in which the adaptive optical device is applied to various optical devices will be described.

FIG. 5 shows an adaptive optics apparatus according to an embodiment of the present invention. In FIG. 5, reference numeral 14 denotes a laser beam, 15 denotes a laser wavefront, 16 denotes a beam splitter, 17 denotes a deformable mirror, 18 denotes a wavefront detector, 19 denotes a control device, and 20 denotes an adaptive optical device. is there. One of the laser beams 14 input to the adaptive optics device 20 is input to the wavefront detector 18 and the other to the deformable mirror 17 by the beam splitter 16.
In the wavefront detector 18, the laser wavefront 1 of the laser beam 14 is used.
5 is detected. The detection method of the laser wavefront 15 includes a Hartmann method, a sharing interference method, and a multi-dithering method.
There are methods and the like, and detection is possible using any method.

The laser wavefront 15 detected by the wavefront detector 18
In order to correct the distortion of the laser wavefront 15, the controller 19 determines the driving amount of each of the stacked piezoelectric elements 1 of the deformable mirror 17 according to the detection signal, and sends the command value to the deformable mirror 17. give. Since the shape of the deformable mirror 17 changes according to a command from the control device 19, the distortion of the laser wavefront 15a of the laser beam 14a reflected from the deformable mirror 17 can be corrected. According to this, as described above, since the mounting density of each laminated piezoelectric element 1 of the deformable mirror 17 can be increased, it is possible to provide an adaptive optics device with high spatial resolution and high compensation efficiency, and further maintenance. Since the deformable mirror 17 having high maintainability is used, an adaptive optics device having high maintainability can be provided.

Further, since the adaptive optical device 20 can precisely correct the wavefront distortion of the laser and the light, it can be applied to various optical devices to suppress the deterioration of the performance due to the wavefront distortion. Hereinafter, various optical devices to which the adaptive optics device is applied will be described.

FIG. 6 is a block diagram showing an embodiment in which the adaptive optics apparatus 20 according to an embodiment of the present invention is applied to an astronomical telescope 22. In the figure, the observation wave 2 from the celestial body 21 to be observed
4 is condensed by the astronomical telescope 22 and input to the adaptive optics device 20 via the lens 23. Since the adaptive optics device 20 can detect and correct the wavefront distortion of the observation wave 24 as described above, the observational wave 24a output from the adaptive optics device 20 has no wavefront distortion, and this is transmitted through the lens 23a to the observation device 24a. 2
If the observation is made at 5, the angular resolution can be improved. In the astronomical telescope 22 installed on the earth, the observation wave 2
Since the wavefront of No. 4 is distorted in the atmosphere, only an angular resolution nearly two orders of magnitude worse than the diffraction limit can be obtained. However, by applying the adaptive optics device 20, the angular resolution close to the diffraction limit can be obtained.

FIG. 7 shows the basic structure of the laser isotope separation apparatus. The substance containing the isotope to be separated is put into the container 28 and heated to evaporate. As a result, the substance which has become the vapor 30 is irradiated with a laser beam having a specific wavelength for ionizing only the isotope to be separated. The isotope ionized by the laser irradiation can be attached to the recovery electrode 31 and extracted. In order to efficiently irradiate the laser beam 27 output from the laser oscillator 26 to the steam 30, the steam 30 is formed by using a plurality of folded mirrors 29.
Is irradiated over a wide area. At this time, laser beam 2
Wavefront distortion occurs when the laser beam 7 propagates through the vapor, and the laser beam 27
However, there arises a problem that the data cannot be propagated due to diffusion or bending. In order to solve this, an adaptive optics device may be applied to the laser isotope separation device 32.
FIG. 8 shows an application of the adaptive optics device.

In the laser isotope separation device 32 shown in FIG. 8, a laser beam 27 output from a laser oscillator 26 is provided.
Is reflected by the deformable mirror 17a, and the beam splitter-1
One is input to the deformable mirror 17b and the other is input to the wavefront detector 18a through the 6a. Based on the wavefront distortion detected by the wavefront detector 18a, the controller 19a determines the command value of the deformable mirror 17a to correct the wavefront distortion. In the same operation, the wavefront distortion is corrected by the deformable mirror 17b, so that the laser beam 27 propagates in the vapor between the deformable mirrors 17a and 17b and the beam splitters 16a and 16b without diffusion or bending. It becomes possible. In the embodiment shown in FIG. 8, the laser beam 27 is a deformable mirror 17a, 1
7b and the beam splitters 16a and 16b alone, but as shown in FIG.
There is no problem even if the adaptive optics device is inserted during the turn-back with the use of the adaptive optics 9.

FIG. 9 is a block diagram of an embodiment in which the adaptive optics apparatus 20 according to one embodiment of the present invention is applied to a laser beam machine 38. The laser beam 34 output from the laser oscillator 33 is reflected at right angles by the beam splitter 16 and input to the variable shape mirror 17 constituting the adaptive optics device 20, and the beam split by the beam splitter 16 is converted into a wavefront detector 18.
The controller 19 controls the shape of the deformable mirror 17 so as to correct the distortion of the laser wavefront by the detected wavefront.
Laser beam 34 whose distortion has been corrected by deformable mirror 17
“a” is condensed into a fine spot by a condenser lens 35 and is irradiated on a workpiece 36 fixed on a processing table 37,
Processing such as drilling, cutting, welding, and surface modification is performed on the workpiece 36 by the high energy density impact of the beam. The beam condensed by the condenser lens 35 is corrected for wavefront distortion by the adaptive optics device 20, so that a beam spot having a high roundness is obtained, thereby concentrating energy at one point and improving processing efficiency and processing accuracy. , A high-performance processing machine can be obtained.

[0023]

As described above, according to the piezoelectric element array of the present invention, since a plurality of laminated piezoelectric elements are mounted on the pedestal and then filled with an insulating material between and around the elements, the mounting of the laminated piezoelectric elements is achieved. Density can be increased.

According to the deformable mirror of the present invention, the plurality of piezoelectric element arrays are provided in a structure that can be individually removed, so that a deformable mirror having high spatial resolution and high maintainability can be provided.

Further, according to the laser or the adaptive optics apparatus for correcting the wavefront distortion of the light wave according to the present invention, since the above-mentioned deformable mirror having high spatial resolution and high maintainability is used, the compensation efficiency and the reliability are improved. It is possible to provide a device having high maintainability and high maintainability.

According to the present invention, an astronomical telescope can be provided with a high-resolution astronomical telescope by applying the above-described compensation optical device having high compensation efficiency and high reliability to an astronomical telescope. Thus, a high-performance processing machine can be provided in which processing efficiency and processing accuracy are enhanced by a laser beam having a high roundness.

Various optical devices such as a laser isotope separation device which can provide a laser isotope separation device with high laser irradiation efficiency by applying a highly efficient compensation optical device to the laser isotope separation device. Reliability can be improved.

[Brief description of the drawings]

FIG. 1 is a structural diagram of a deformable mirror according to an embodiment of the present invention.

FIG. 2 is a structural view of a piezoelectric element array according to an embodiment of the present invention.

FIG. 3 is a structural view of a piezoelectric element array according to another embodiment of the present invention.

FIG. 4 is a structural view of a deformable mirror according to another embodiment of the present invention.

FIG. 5 is a configuration diagram of an adaptive optics device according to an embodiment of the present invention.

FIG. 6 is a configuration diagram of an astronomical telescope according to an embodiment of the present invention.

FIG. 7 is a configuration diagram of a laser isotope separation device.

FIG. 8 is a configuration diagram of a laser isotope separation apparatus according to an embodiment of the present invention.

FIG. 9 is a configuration diagram of a laser processing machine according to an embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Laminated piezoelectric element, 2 ... External electrode, 3 ... Pedestal, 4 ... Insulating material, 5 ... Lead wire, 6, 61 ... Piezoelectric element array, 7 ...
Lens barrel, 8 screws, 9 pins, 10 plates, 11 mirrors, 12 screw portions, 13 nuts, 14 and 14a laser beam, 15 and 15a laser wavefront, 16,16
a, 16b ... beam splitters, 17, 17a, 17
b: deformable mirror, 18, 18a, 18b: wavefront detector,
19, 19a, 19b: control device, 20: adaptive optical device, 21: astronomical object, 22: astronomical telescope, 23, 23a: lens, 24, 24a: observation wave, 25: observation device, 26 ...
Laser oscillator, 27 ... Laser beam, 28 ... Container, 29
... Folded mirror, 30 ... Steam, 31 ... Recovery electrode, 32 ...
Laser isotope separator, 33 laser oscillator, 34, 3
4a: laser beam, 35: focusing lens, 36: workpiece, 37: processing table, 38: laser processing machine.

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields surveyed (Int. Cl. ⁷ , DB name) H01L 41/08 G01J 1/04 G02B 23/12 G02B 26/00 H01S 3/00

Claims (7)

(57) [Claims] 1. A laser beam or deformable mirror capable of changing the wavefront of the light, a piezoelectric material and both sides
Multiple piezoelectric elements with conductive material attached as positive and negative electrodes
Stacked piezoelectric with stacked piezoelectric elements electrically connected in parallel
A plurality of elements are arranged one-dimensionally on a flat plate, and
Piezoelectric element array formed by filling and covering between and around layered piezoelectric elements with an insulating material, pins attached to each laminated piezoelectric element of the piezoelectric element array, and piezoelectric element array attached with the pins removably mounting the lens barrel with a laser beam or an interval corresponding to the angle of the light is incident a plurality in the deformable mirror, and characterized in that it comprises providing a mirror that removably coupled to the respective pin Variable shape mirror. 2. A deformable mirror capable of changing a wavefront of a laser beam or light, comprising: a piezoelectric material;
Multiple piezoelectric elements with conductive material attached as positive and negative electrodes
Stacked piezoelectric with stacked piezoelectric elements electrically connected in parallel
A plurality of elements are two-dimensionally arranged on a flat plate, and
Piezoelectric element array formed by filling and covering between and around layered piezoelectric elements with an insulating material, pins attached to each laminated piezoelectric element of the piezoelectric element array, and piezoelectric element array attached with the pins The lens barrel detachably mounted and the above pins
A deformable mirror characterized by comprising a mirror detachably coupled to the mirror. 3. A deformable mirror according to claim 1 or claim 2, characterized by comprising attached a plurality of piezoelectric element arrays with attached the pin to the barrel with a screw thread. 4. A wavefront detector and the controller and the adaptive optical device comprising a deformable mirror to determine the control amount from the detected value detected wavefront distortion of a laser beam or light, according to claim 1, claim 2, and, adaptive optical apparatus characterized in that a deformable mirror according to claim 3. 5. A telescope for observing enter the observation wave in the observation device, an adaptive optical device according to claim 4 for inputting the previous observation wave input to the observation apparatus provided, the distortion by the adaptive optical device An astronomical telescope, wherein the observation wave is corrected and input to the observation device. 6. A laser isotope separation apparatus in which a laser beam output from a laser oscillator is repeatedly reflected and radiated onto a vaporized vapor of the substance while the laser beam is repeatedly reflected in order to extract an isotope element contained in the substance. 2. The method according to claim 1 , wherein the laser beam is reflected at a return position.
2 , and a plurality of the deformable mirrors and the beam splitters according to any one of claims 3 are alternately provided, and each wavefront detector for detecting a wavefront distortion of the laser beam divided by each of the beam splitters is provided; and A laser isotope separation apparatus comprising: a control unit that controls each of the deformable mirrors based on a detection value of each of the wavefront detectors. 7. A laser processing machine for irradiating a workpiece machined with a laser beam focused by the lens of the laser oscillator of claim 4 wherein the input laser beam prior to input to the condenser lens A laser processing machine comprising an adaptive optics device, wherein the laser beam is corrected into a laser beam without distortion by the adaptive optics device, and then input to the condenser lens.