JP2002035980A - Device and method for laser beam processing, and laser beam oscillator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To conduct high quality working by converting intensity distribution of a laser beam on a processing object so as to be uniform distribution in a laser beam processing device where an image of a mask is projected on a processing object and processed. SOLUTION: A laser beam 102 from a laser beam oscillator 101 is divided by means of a S/P separating mirror 104, intensity distribution of one laser beam 102a is converted in an annular zone shape by means of a phase shift member 105 on a mask 113, and the other laser beam 102b is maintained in a gauss shape and propagated on the mask 113. Since polarizing distribution of the laser beam 102a and 102b are vertical, intensity distribution of a synthesized laser beam 102c on the mask becomes added value of intensity of each laser beam and can be uniformed. Furthermore, since polarizing distribution of the laser beam on the processing object is uniformed by projecting the image of a mask by a projection lens 114 on a processing object 115, quality processing can be conducted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a laser processing apparatus, a laser processing method, and a laser oscillator.
A laser processing apparatus and method for projecting and processing an image of a mask having an opening of an arbitrary shape on a workpiece using a laser beam having a high spatial coherency such as an O2 laser or a YAG laser, and a CO2 laser or a YAG laser The present invention relates to a laser oscillator that oscillates a laser beam with high uniform spatial coherency.

[0002]

2. Description of the Related Art A conventional technique relating to the above-described laser processing apparatus will be described with reference to the drawings. FIG. 5 is a configuration diagram of a conventional laser processing apparatus. In FIG. 5, reference numeral 51 denotes a laser oscillator, and 52 denotes a laser beam. The profile is shown by a dotted line in the drawing. 53 is a telescope, 54 is a mask, 55
Denotes a projection lens, and 56 denotes an object to be processed.

[0003] A laser beam 52 emitted from a laser oscillator 51 passes through a telescope 53 and enters a mask 54. The size of the mask 54 is variable. In some cases, the size of the aperture of the mask is determined based on the size of the hole to be processed. In other cases, the size of the mask is not variable but a different size mask is used depending on the processing. The telescope 53 is designed such that the beam diameter of the laser beam 52 incident on the mask and the curvature of the wavefront are optimal for processing.

[0004] A projection lens 55 projects the image of the mask onto a processing target 56, and performs drilling on a processing target such as a printed circuit board.

Further, in the prior art, a number of processes can be performed in a short time by scanning a laser beam with a galvano mirror or moving a stage at a high speed between processes. .

[0006]

However, the laser processing apparatus as shown in the prior art has the following problems. In laser processing, for example, quenching, welding, and drilling of a build-up multilayer substrate when the resin contains a large amount of glass fiber, the intensity distribution of the laser beam on the workpiece has a uniform distribution. Is desirable.

However, in the case of a CO2 laser, a YAG laser or the like, the intensity distribution of the laser beam is close to a so-called Gaussian distribution in which the intensity is high near the optical axis and decreases exponentially toward the periphery. .

When such a laser beam is used, for example, for drilling the above-described build-up multilayer substrate, the fiber protrusion on the inner wall of the via becomes long, which causes a failure in a post-process such as plating.

In a conventional laser processing apparatus, the laser beam is enlarged sufficiently to the opening of the mask by using a collimator, and only the optical axis of the laser beam and a region where the intensity is high in the vicinity thereof are processed. However, when such a device is used, the energy of the laser beam blocked by the shielding portion of the mask increases, resulting in a reduction in the energy utilization rate.

Conventionally, there is a method of generating a multi-mode laser beam and using the laser beam with an intensity distribution close to a uniform distribution. However, the order of a multimode laser beam generally changes with a change in the laser output, and the intensity distribution tends to fluctuate. As a result, there is a problem that the strength distribution on the machined surface changes and machining performance cannot be stabilized.

According to the present invention, in laser processing in which an image of a mask is projected onto a processing target to process the laser beam, the intensity distribution of the laser beam on the processing target is converted into a uniform distribution, thereby achieving high efficiency. The purpose is to perform high-quality processing.

[0012]

SUMMARY OF THE INVENTION In order to solve this problem, the present invention provides a laser oscillator that oscillates a laser beam having a Gaussian intensity distribution, a mask for cutting the laser beam into an arbitrary cross-sectional shape, and the mask A projection optical system for projecting the image of the laser beam onto the object to be processed, means for splitting the laser beam into two in front of the mask, converting both of the split laser beams into linearly polarized light, and Means for vertically changing the polarization direction of the laser beam, means for making the intensity distribution of one of the divided laser beams into an annular shape on the mask, and means for combining the two laser beams divided before the mask. The intensity distribution of the laser beam on the object to be processed becomes a uniform distribution according to the size of the mask, and high-quality processing can be performed.

A laser oscillator for oscillating a laser beam having a Gaussian intensity distribution; a mask for cutting the laser beam into an arbitrary cross-sectional shape; and a projection optical system for projecting an image of the mask onto a workpiece. Means for dividing the laser beam into two linearly polarized laser beams having a perpendicular polarization direction in front of the mask; means for forming an intensity distribution of one of the divided laser beams into an annular shape on the mask; It combines the two laser beams divided before and the means for combining the two laser beams. In the object to be processed, the intensity distribution of the laser beam becomes a uniform distribution according to the size of the mask, and high quality processing can be performed.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 of the present invention is directed to a laser oscillator that oscillates a laser beam having a Gaussian intensity distribution, a mask for cutting the laser beam into an arbitrary cross-sectional shape, and a mask for the mask. A projection optical system for projecting an image onto a processing object, a means for dividing the laser beam into two in front of the mask, a means for converting both laser beams into linearly polarized light and Means for vertically changing the polarization direction of the laser beam, means for making the intensity distribution of one of the divided laser beams into an annular shape on the mask, and means for combining the two laser beams divided before the mask. With this configuration, the laser beam intensity distribution on the object to be processed becomes a uniform distribution according to the size of the mask, and high-quality processing can be performed.

According to a second aspect of the present invention, there is provided a laser oscillator for oscillating a laser beam having a Gaussian intensity distribution, a mask for cutting the laser beam into an arbitrary cross-sectional shape,
A projection optical system for projecting an image of the mask onto a processing target, and a means for splitting the laser beam into two linearly polarized laser beams having a perpendicular polarization direction in front of the mask; A laser processing apparatus having means for making the intensity distribution of a laser beam annular in shape on a mask, and means for synthesizing two laser beams split in front of the mask. The intensity distribution becomes uniform according to the size of the mask, and high quality processing can be performed.

More specifically, in the invention according to claim 3, the means for making the intensity distribution of one of the divided laser beams into an annular shape on the mask is a polar coordinate in a plane perpendicular to the traveling direction of the laser beam. A phase shift member formed to shift the phase of the laser beam by the same angle as the declination of the polar coordinate system; a condensing optical system disposed after the phase shift member; and the condensing optical system. 3. The laser processing apparatus according to claim 1, further comprising: a projection optical system configured to project an image of a focal point of the laser beam focused by the laser beam onto a position of the mask. 3. In this case, the intensity distribution of the laser beam becomes uniform according to the size of the mask, and high quality processing can be performed.

According to a fourth aspect of the present invention, the means for making the intensity distribution of one of the divided laser beams into an annular shape on the mask is a polar coordinate system in a plane perpendicular to the traveling direction of the laser beam. Declination from 0 radians to 2π
The area up to radians is divided into areas divided by an arbitrary number, and within each of the divided areas, the phase of the laser beam is shifted by the same angle, and the angle falls within the range of the declination of the polar coordinates in each area. A phase shift member formed so as to be included, a condensing optical system disposed after the phase shift member, and an image of a condensing point of the laser beam condensed by the condensing optical system at a position of a mask. 3. A laser processing apparatus according to claim 1, wherein said laser processing apparatus comprises a projection optical system for projecting the laser beam onto the object to be processed. , High quality processing is possible.

According to a fifth aspect of the present invention, the means for making the intensity distribution of one of the divided laser beams into an annular shape on a mask has the optical axis as an axis in a plane perpendicular to the traveling direction of the laser beam. A phase shift member formed to shift the phase of the laser beam in an annular shape, a condensing optical system arranged after the phase shift member, and a laser beam condensed by the condensing optical system. 3. The laser processing apparatus according to claim 1, further comprising: a projection optical system configured to project an image of a light-converging point onto the position of the mask. 3. The distribution becomes uniform according to the size, and high quality processing can be performed.

More specifically, the invention according to claim 6 is
The laser processing apparatus according to any one of claims 3 to 5, wherein the phase shift member is formed integrally with the condensing optical system, and with this configuration, the intensity distribution of the laser beam on the object to be processed. Has a uniform distribution according to the size of the mask, and high quality processing can be performed.

According to a seventh aspect of the present invention, a step of oscillating a laser beam having a Gaussian intensity distribution, a step of cutting the laser beam into an arbitrary sectional shape,
Projecting an image of the cross section of the cut laser beam onto a processing target, further dividing the laser beam into two before cutting the laser beam into an arbitrary cross-sectional shape; Converting the two laser beams into linearly polarized light and converting the polarization directions of the two laser beams vertically, and changing the intensity distribution of one of the divided laser beams at a position where the laser beam is cut into an arbitrary cross-sectional shape. A laser processing method having a step of forming an annular shape and a step of combining two laser beams divided before a position at which the laser beam is cut into an arbitrary cross-sectional shape. The intensity distribution becomes uniform according to the size of the mask, and high-quality processing can be performed.

The present invention according to claim 8 is a step of oscillating a laser beam having a Gaussian intensity distribution, a step of cutting the laser beam into an arbitrary cross-sectional shape, and an image of a cross section of the cut laser beam. Projecting the laser beam on a processing object, further dividing the laser beam into two linearly polarized laser beams having a perpendicular polarization direction before cutting the laser beam into an arbitrary cross-sectional shape, Making the intensity distribution of one of the divided laser beams into an annular shape at a position where the laser beam is cut into an arbitrary cross-sectional shape; and two laser beams split before the position where the laser beam is cut into an arbitrary cross-sectional shape. Synthesizing a laser beam by the method. Becomes uniform distribution in accordance with the size of the mask, good processing can be quality.

According to a ninth aspect of the present invention, the step of forming the intensity distribution of one of the divided laser beams into an annular shape at a position where the laser beam is cut into an arbitrary cross-sectional shape includes the step of: Shifting the phase of the laser beam by the same angle as the declination of the polar coordinate in a polar coordinate system in a plane perpendicular to the plane; condensing the phase-shifted laser beam; and Projecting an image of the beam focusing point onto the position of the mask.
This is a laser processing method described above. With this method, the intensity distribution of the laser beam in the processing target becomes a uniform distribution according to the size of the mask, and high-quality processing can be performed.

According to a tenth aspect of the present invention, the step of forming the intensity distribution of one of the divided laser beams into an annular shape at a position where the laser beam is cut into an arbitrary cross-sectional shape is performed.
In a polar coordinate system in a plane perpendicular to the direction of travel of the laser beam, the angle between the polar coordinate declination from 0 radians to 2π radians is divided into an arbitrary number of divided areas, and within each divided area, the same is applied. Shifting the phase of the laser beam by an angle so that the angle is within the range of polar declination in each region; focusing the phase shifted laser beam; Projecting the image of the focused point of the laser beam onto a position of a mask, wherein the intensity distribution of the laser beam on the object to be processed is obtained by this method. Has a uniform distribution according to the size of the mask, and high quality processing can be performed.

According to the eleventh aspect of the present invention, the step of forming the intensity distribution of one of the divided laser beams into an annular shape at a position where the laser beam is cut into an arbitrary cross-sectional shape is performed.
Shifting the phase of the laser beam in an annular shape around an optical axis in a plane perpendicular to the direction of travel of the laser beam; condensing the phase-shifted laser beam; 9. The laser processing method according to claim 7, further comprising the step of: projecting an image of the focal point of the laser beam onto a position of a mask. The distribution becomes uniform according to the size of, and high quality processing can be performed.

More specifically, the invention described in claim 12 is
Focusing the phase-shifted laser beam;
And projecting an image of the condensed point of the condensed laser beam onto a position of a mask.
According to this method, the intensity distribution of the laser beam on the object to be processed becomes a uniform distribution according to the size of the mask, and high-quality processing can be performed.

According to a thirteenth aspect of the present invention, there is provided an optical resonator which oscillates a laser beam having a Gaussian intensity distribution, means for splitting the laser beam into two, and both of the split laser beams. Means for converting the laser beam into linearly polarized light and the polarization directions of the two laser beams vertically; means for making the intensity distribution of one of the divided laser beams into an annular shape at a predetermined position; Means for synthesizing the two laser beams thus obtained,
With this configuration, the intensity distribution of the laser beam at a predetermined position becomes uniform, and the laser oscillator of the present invention is used in a laser processing device to project a uniform intensity distribution at a predetermined position on a processing target. The intensity distribution of the laser beam on the object becomes a uniform distribution according to the size of the mask, and high quality processing can be performed.

More specifically, the invention described in claim 14 is
An optical resonator that oscillates a laser beam having a Gaussian intensity distribution; a unit that divides the laser beam into two linearly polarized laser beams whose polarization directions are perpendicular; and an intensity distribution of one of the divided laser beams. A laser oscillator having means for forming an annular shape at a position and means for synthesizing two laser beams divided in front of a predetermined position. This configuration makes the intensity distribution of the laser beam at the predetermined position uniform. By using the laser oscillator of the present invention in a laser processing apparatus and projecting a uniform intensity distribution at a predetermined position on a processing target, the intensity distribution of the laser beam in the processing target is uniform according to the size of the mask. Distribution and high quality processing.

According to a fifteenth aspect of the present invention, the means for making the intensity distribution of one of the divided laser beams into an annular shape at a predetermined position is a polar coordinate system in a plane perpendicular to the traveling direction of the laser beam. Only the same angle as the polar declination,
A phase shift member formed to shift the phase of the laser beam, a condensing optical system disposed after the phase shift member, and an image of a condensing point of the laser beam condensed by the condensing optical system 15. A laser oscillator according to claim 13, wherein said laser oscillator comprises a projection optical system for projecting the laser beam onto said predetermined position. By projecting a uniform intensity distribution at a predetermined position on the processing object using the oscillator in the laser processing apparatus, the intensity distribution of the laser beam in the processing object becomes a uniform distribution according to the size of the mask, High quality processing is possible.

According to a sixteenth aspect of the present invention, the means for making the intensity distribution of one of the divided laser beams into an annular shape at a predetermined position is a polar coordinate system in a plane perpendicular to the traveling direction of the laser beam. The polar coordinate declination from 0 radians to 2π radians is divided into areas divided by an arbitrary number, and within each of the divided areas, the phase of the laser beam is shifted by the same angle, and the angle is shifted within each area. A phase shift member formed so as to be included within the range of the declination of the polar coordinates, a focusing optical system disposed after the phase shift member, and focusing of the laser beam focused by the focusing optical system. 15. The laser oscillator according to claim 13, further comprising a projection optical system configured to project a point image onto the predetermined position, whereby the laser beam intensity distribution at the predetermined position becomes uniform. By using the laser oscillator of the present invention in a laser processing apparatus and projecting a uniform intensity distribution at a predetermined position on a processing target, the intensity distribution of the laser beam on the processing target is uniform according to the size of the mask. It becomes distribution, and high quality processing can be performed.

According to a seventeenth aspect of the present invention, the means for making the intensity distribution of one of the divided laser beams into an annular shape at a predetermined position has the optical axis as an axis in a plane perpendicular to the traveling direction of the laser beam. A phase shift member formed to shift the phase of the laser beam in an annular shape, a condensing optical system disposed after the phase shift member, and condensing of the laser beam condensed by the condensing optical system 2. A projection optical system for projecting a point image onto the predetermined position.
15. The laser oscillator according to 3 or 14, wherein this configuration makes the intensity distribution of the laser beam at a predetermined position uniform, and uses the laser oscillator of the present invention in a laser processing apparatus to produce a uniform intensity distribution at a predetermined position. By projecting the laser beam on the processing target, the intensity distribution of the laser beam on the processing target becomes a uniform distribution according to the size of the mask, and high-quality processing can be performed.

More specifically, the invention according to claim 18 is
The laser oscillator according to any one of claims 15 to 17, wherein the phase shift member is formed integrally with the focusing optical system,
With this configuration, the intensity distribution of the laser beam at a predetermined position becomes uniform, and the laser oscillator of the present invention is used in a laser processing device to project a uniform intensity distribution at a predetermined position on a processing target. The intensity distribution of the laser beam on the object becomes a uniform distribution according to the size of the mask, and high quality processing can be performed.

Hereinafter, an embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIG.

(Embodiment) FIG. 1 is a schematic configuration diagram of a laser processing apparatus according to an embodiment of the present invention. In FIG. 1, 101 is a laser oscillator, 102 is a laser beam,
102a is one separated laser beam, 102b is the other separated laser beam, 102c is a combined laser beam, 103 is a phase retarder, 104 is an S / P separation mirror, 105 is a phase shift member, and 106 is a collecting beam. Optical lens, 107 is a beam waist position, 108 is a projection optical system, 109 is a total reflection mirror, 110 is a telescope, 11
1 is a total reflection mirror, 112 is an S / P separation mirror, 113 is a mask, 114 is a projection lens, and 115 is an object to be processed.

Next, the operation will be described. The laser oscillator 101 oscillates a linearly polarized laser beam 102 having a Gaussian intensity distribution. The laser beam 102 is shown by a dotted line in the figure. The phase retarder 103 controls the direction of oscillation of the polarization of the laser beam 102.

The S / P separating mirror 104 is provided with a P-polarized light,
The laser beam 102 is separated into polarized light components. Specifically, the S / P separation mirror 104 transmits a P-polarized laser beam and reflects an S-polarized laser beam. S / P separation mirror 1
Reference numeral 102a denotes a laser beam transmitted through the laser beam 04, and reference numeral 102b denotes a laser beam reflected by the S / P separation mirror 104.

The phase shift member 105 shifts the phase of the laser beam in the polar coordinate system in a plane perpendicular to the traveling direction of the laser beam 102a by the same angle as the polar coordinate declination.

FIG. 2A shows that the phase shift member 105 is
FIG. 3 is a diagram viewed obliquely from a plane perpendicular to the optical axis. The phase shift member 105 is connected to the laser beam 102a.
The thickness d (mm) of the film is given in a polar coordinate system in a plane perpendicular to the optical axis in the form of (Formula 1) as follows: .

[0038]

(Equation 1)

In equation (1), λ is the laser beam 102
Is the wavelength (mm), n is the refractive index θ of the transmission film, and the declination (radian) of the polar coordinate system. Then, the condenser lens 106 is disposed immediately after the phase shift member 105, and the laser beam 1
Focus 02a.

The laser beam 102a, which is phase-shifted by the phase shift member 105 and is focused by the focusing lens 106
Is the best focus position, that is, beam waist position 1
At 07, the intensity distribution becomes annular. Then, the projection optical system 108 projects the image at the beam waist position 107 on the position of the mask 113.

Next, the laser beam 102 b reflected by the S / P separation mirror 104 is reflected by the total reflection mirror 109 and enters the telescope 110. The telescope 110 controls the laser beam 102b to have an appropriate beam diameter and a wavefront curvature on the mask.

The laser beam 102b reflected by the total reflection mirror 111 is synthesized by the S / P separation mirror 112 so that the beam position and the traveling direction of the laser beam 102a coincide with each other, that is, the optical axis coincides. You. The combined laser beam is called a laser beam 102c.

With such a configuration, the intensity distribution of the laser beam 102c on the mask 113 becomes
02a and the intensity distribution of the laser beam 102b.

FIG. 3A shows the intensity distribution of the laser beam 102a on the mask 112, and FIG. 3B shows the intensity distribution of the laser beam 112b. The intensity distribution of the laser beam 102a on the mask 112 is annular because the image of the beam waist position 107 is reproduced, and the intensity distribution of the laser beam 112b is Gaussian because the phase distribution is not subjected to phase modulation.

The intensity distribution of the laser beam 112c is the sum of the intensity distribution shown in FIG. 3A and the intensity distribution shown in FIG. 3B, and a uniform distribution as shown in FIG. It can be.

In order to make the intensity of the laser beam 102c on the mask uniform, the intensity distribution of the laser beam 102a on the mask 112 and the intensity of the laser beam 102b
In this embodiment, the beam diameter adjusts the projection magnification of the projection optical system 108 for the laser beam 102a, and the beam diameter of the laser beam 102b is adjusted for the laser beam 102b. The adjustment was performed by moving the convex lens constituting the telescope 110 along the optical axis.

The ratio between the intensities of the laser beam 102a and the laser beam b was adjusted by controlling the oscillation direction of the laser beam 102 with a phase retarder.

Here, if the polarization directions of the two laser beams to be combined are not perpendicular, the intensity distribution of the two combined laser beams causes interference without adding the intensities. In this case, since the phase of the laser beam whose phase has been shifted by the phase shift member 105 is not axially symmetric, the intensity distribution of the combined laser beam on the mask is absolutely asymmetric and not uniform. Then, the projection lens 114 projects the image of the mask 113 onto the processing target.

With the laser processing apparatus described above, the intensity distribution of the laser beam on the object to be processed can be made uniform, and high-quality processing can be performed.

In the present embodiment, the phase shift member 105 is used to shift the phase of the laser beam 102a by the same angle as the declination of the polar coordinate in a polar coordinate system in a plane perpendicular to the traveling direction of the laser beam 102a. However, in the polar coordinate system in a plane perpendicular to the traveling direction of the laser beam 102a, the polar coordinate declination from 0 radians to 2π radians is divided into areas divided by an arbitrary number and divided. In each region, the phase of the laser beam 102a may be shifted by the same angle, and the phase of the laser beam 102a may be shifted so that the angle is included in the range of the polar declination in each region.

Specifically, the phase may be shifted as shown in FIG. The horizontal axis of FIG. 4 is the polar coordinate declination in a plane perpendicular to the optical axis, and the vertical axis is the phase shift amount of the phase shift member. Even when such a phase shift member is used, the laser beam 10
The intensity distribution of 2a has an annular shape, and the same effect as in the above embodiment can be obtained.

Further, in the present embodiment, the phase shift member 105 is used to change the phase of the laser beam 102a by the same angle as the declination of the polar coordinate in a polar coordinate system in a plane perpendicular to the traveling direction of the laser beam 102a. Although it is assumed that the phase of the laser beam is shifted in an annular shape around the optical axis in a plane perpendicular to the direction of travel of the laser beam, the phase shift on the mask 113 is performed similarly to the above embodiment. The intensity distribution of the laser beam 102a has an annular shape, and the same effect as in the above embodiment can be obtained.

[0053]

As described above, according to the present invention, the intensity distribution of a laser beam on a workpiece becomes uniform in laser processing for processing by projecting an image of a mask on a workpiece. , And an advantageous effect that high-quality processing can be performed can be obtained.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a laser processing apparatus according to an embodiment of the present invention.

FIG. 2 is a perspective view of a phase shift member according to one embodiment of the present invention.

FIG. 3A is a characteristic diagram of an intensity distribution of one separated laser beam on a mask according to one embodiment of the present invention; and FIG. 3B is another separated laser beam according to one embodiment of the present invention. (C) Characteristic diagram of intensity distribution on mask of combined laser beam in one embodiment of the present invention

FIG. 4 is a characteristic diagram showing a phase shift amount in a polar coordinate system in a plane perpendicular to a traveling direction of a laser beam by a phase shift member according to an embodiment of the present invention.

FIG. 5 is a schematic configuration diagram of a laser processing apparatus in a conventional example.

[Explanation of symbols]

 Reference Signs List 101 laser oscillator 102 laser beam 102a laser beam 102b laser beam 102c laser beam 103 phase retarder 104 S / P separation mirror 105 phase shift member 106 condensing lens 107 beam waist position 108 projection optical system 109 total reflection mirror 110 telescope 111 total reflection Mirror 112 S / P separation mirror 113 Mask 114 Projection lens 115 Workpiece 51 Laser oscillator 52 Laser beam 53 Uniform optical system 54 Projection optical system 55 Mask 56 Aperture stop 57 Projection lens 58 Workpiece

Continued on the front page (72) Inventor Hidehiko Karasaki 1006 Kazuma Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. F-term (reference) 4E068 CB10 CD03 CD05 CD10 5F072 AA05 AB01 JJ20 KK05 KK15 KK30 YY06

Claims (18)

[Claims] 1. A laser oscillator for oscillating a laser beam having a Gaussian intensity distribution, a mask for cutting the laser beam into an arbitrary cross-sectional shape, and a projection optical system for projecting an image of the mask onto a processing target. Means for splitting the laser beam into two parts in front of the mask, means for converting both laser beams into linearly polarized light and means for vertically changing the polarization direction of both laser beams When,
A laser processing apparatus comprising: means for making an intensity distribution of one of the divided laser beams into an annular shape on a mask; and means for combining two laser beams divided in front of the mask. 2. A laser oscillator for oscillating a laser beam having a Gaussian intensity distribution, a mask for cutting the laser beam into an arbitrary cross-sectional shape, and a projection optical system for projecting an image of the mask onto a processing target. Means for dividing the laser beam into two linearly polarized laser beams whose polarization directions are perpendicular to each other in front of the mask, means for making the intensity distribution of one of the divided laser beams into an annular shape on the mask, Means for synthesizing the two laser beams split before the laser beam. 3. A means for making the intensity distribution of one of the divided laser beams into an annular shape on a mask, in the polar coordinate system in a plane perpendicular to the traveling direction of the laser beam, by an angle equal to the declination of the polar coordinates. A phase shift member formed to shift the phase of the laser beam, a focusing optical system disposed after the phase shift member, and focusing of the laser beam focused by the focusing optical system. The laser processing apparatus according to claim 1, further comprising a projection optical system configured to project a point image onto the position of the mask. 4. A means for converting the intensity distribution of one of the divided laser beams into an annular shape on a mask, wherein the polarizer system is arranged such that, in a polar coordinate system in a plane perpendicular to a traveling direction of the laser beam, a deviation of 0 radians in polar coordinates is obtained. The area up to 2π radians is divided into areas divided by an arbitrary number, and within each of the divided areas, the phase of the laser beam is shifted by the same angle so that the angle is within the range of the polar coordinate declination in each area. A phase shift member formed so as to be included in, a condensing optical system disposed after the phase shift member, and an image of a condensing point of the laser beam condensed by the condensing optical system on a mask. The laser processing apparatus according to claim 1, wherein the laser processing apparatus is configured by using a projection optical system that projects onto a position. 5. A means for making the intensity distribution of one of the divided laser beams into an annular shape on the mask, wherein the laser beam is formed into an annular shape around an optical axis in a plane perpendicular to the traveling direction of the laser beam. A phase shift member formed so as to shift the phase, a condensing optical system disposed after the phase shift member, and an image of a condensing point of the laser beam condensed by the condensing optical system. 3. The laser processing apparatus according to claim 1, wherein the laser processing apparatus is configured using a projection optical system for projecting the position on the mask. 6. The laser processing apparatus according to claim 3, wherein the phase shift member is formed integrally with the focusing optical system. 7. A step of oscillating a laser beam having a Gaussian intensity distribution, a step of cutting the laser beam into an arbitrary cross-sectional shape, and a step of projecting a cross-sectional image of the cut laser beam onto an object to be processed. And
Further, before the step of cutting the laser beam into an arbitrary cross-sectional shape, the step of dividing the laser beam into two, converting both of the divided laser beams into linearly polarized light, and setting the polarization directions of the two laser beams to vertical. Converting the intensity distribution of one of the divided laser beams into an annular shape at a position where the laser beam is cut into an arbitrary cross-sectional shape; and splitting the laser beam before the position where the laser beam is cut into an arbitrary cross-sectional shape. Synthesizing the two laser beams thus obtained. 8. A step of oscillating a laser beam having a Gaussian intensity distribution, a step of cutting the laser beam into an arbitrary cross-sectional shape, and a step of projecting an image of a cross-section of the cut laser beam onto an object to be processed. And
Further, before the step of cutting the laser beam into an arbitrary cross-sectional shape, the step of dividing the laser beam into two linearly polarized laser beams whose polarization directions are perpendicular to each other; A laser processing method comprising: forming an annular shape at a position where the laser beam is cut into an arbitrary cross-sectional shape; and combining two laser beams divided before the position where the laser beam is cut into an arbitrary cross-sectional shape. 9. The step of making the intensity distribution of one of the divided laser beams into an annular shape at a position where the laser beam is cut into an arbitrary cross-sectional shape, in a polar coordinate system in a plane perpendicular to the traveling direction of the laser beam. Shifting the phase of the laser beam by the same angle as the declination of the polar coordinates; condensing the phase-shifted laser beam; and 9. The laser processing method according to claim 7, further comprising: projecting the laser beam onto a position. 10. The step of forming the intensity distribution of one of the divided laser beams into an annular shape at a position where the laser beam is cut into an arbitrary cross-sectional shape, in a polar coordinate system in a plane perpendicular to the traveling direction of the laser beam. The angle between 0 radian and 2π radian of the polar coordinate declination is divided into areas divided by an arbitrary number, and within each of the divided areas, the phase of the laser beam is shifted by the same angle, and the angle is changed in each area. Within the range of the declination of the polar coordinates, focusing the phase-shifted laser beam, and focusing the image of the focused laser beam at the position of the mask. 9. The laser processing method according to claim 7, wherein the laser processing method comprises: projecting. 11. The step of making the intensity distribution of one of the divided laser beams into an annular shape at a position where the laser beam is cut into an arbitrary cross-sectional shape, wherein the optical axis is set in a plane perpendicular to the traveling direction of the laser beam. Shifting the phase of the laser beam in an annular shape, focusing the phase-shifted laser beam, and projecting an image of the focused laser beam at the position of the mask. 9. The laser processing method according to claim 7, wherein the laser processing method comprises: 12. The method according to claim 1, wherein a step of converging the phase-shifted laser beam and a step of projecting an image of the condensed point of the condensed laser beam onto a position of a mask are integrated. The laser processing method according to claim 9. 13. An optical resonator for oscillating a laser beam having a Gaussian intensity distribution, means for splitting the laser beam into two, and converting both of the split laser beams into linearly polarized light. Means for vertically changing the polarization direction of the laser beam, means for making the intensity distribution of one of the divided laser beams into an annular shape at a predetermined position, and combining the two laser beams divided before the predetermined position. And a laser oscillator having means. 14. An optical resonator for oscillating a laser beam having a Gaussian intensity distribution, means for splitting the laser beam into two linearly polarized laser beams whose polarization directions are perpendicular, and one of the split laser beams Means for making the intensity distribution of an annular shape at a predetermined position,
Means for combining two laser beams. 15. A means for making the intensity distribution of one of the divided laser beams into an annular shape at a predetermined position, in the polar coordinate system in a plane perpendicular to the traveling direction of the laser beam, the angle being the same as the declination of the polar coordinates. A phase shift member formed so as to shift the phase of the laser beam, a condensing optical system disposed after the phase shift member, and a condensing point of the laser beam condensed by the condensing optical system. 15. The laser oscillator according to claim 13, wherein the laser oscillator is configured using a projection optical system for projecting the image at the predetermined position. 16. A means for making the intensity distribution of one of the divided laser beams into an annular shape at a predetermined position, the polarizer having a declination of polar coordinates of 0 radians in a polar coordinate system in a plane perpendicular to the traveling direction of the laser beam. To 2π radians is divided into regions divided by an arbitrary number, and in each divided region, the phase of the laser beam is shifted by the same angle,
A phase shift member formed so that the angle is included within the range of polar declination in each region, a condensing optical system disposed after the phase shift member, and light condensed by the condensing optical system. 15. The laser oscillator according to claim 13, further comprising: a projection optical system configured to project an image of a focal point of the laser beam onto the predetermined position. 17. A means for forming an intensity distribution of one of the divided laser beams into an annular shape at a predetermined position, wherein the laser beam is formed into an annular shape around an optical axis in a plane perpendicular to a traveling direction of the laser beam. A phase shift member formed so as to shift the phase of the light beam, a converging optical system disposed after the phase shifting member, and an image of a converging point of the laser beam condensed by the converging optical system. 15. The laser oscillator according to claim 13, further comprising: a projection optical system for projecting the laser beam at a position. 18. The laser oscillator according to claim 15, wherein the phase shift member is formed integrally with the focusing optical system.