JP2003211280A - Device and method of laser generation and method of machining by using laser - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a laser generating device in which the intensity distribution of a laser beam is variable by means of a simple structure and to provide a method of laser beam machining using the device. <P>SOLUTION: The laser generating device 10 is provided with a laser oscillator 1 and an intensity distribution transformation mechanism which equalizes the intensity distribution of the laser beam emitted from the laser oscillator. The intensity distribution transformation mechanism is a cylindrical body 3 which has an internal surface which reflects the laser beam, and the laser generating device is characterized by the fact that the laser beam emitted from the laser oscillator is made incident into the cylindrical body at a prescribed angle and the intensity distribution is transformed. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a laser generator,
The present invention relates to a laser generation method and a processing method using a laser beam. INDUSTRIAL APPLICABILITY The present invention is suitable, for example, for chamfering brittle materials (glass, ceramics) and for joining or welding glass to glass.

[0002]

2. Description of the Related Art For example, mechanical polishing using a grindstone is widely used as a method for chamfering an end surface of glass which is a brittle material.

However, the chamfering method by mechanical polishing has a fear of causing chipping, cracking and damage. Therefore, a chamfering method using a laser beam has been proposed for processing the end surface of glass.

For example, Japanese Patent No. 2612332 discloses a method for chamfering a corner of a glass member, in which a laser beam is applied to a glass member while keeping the entire glass member at a predetermined temperature higher than room temperature. A chamfering method for a glass member, characterized in that the irradiation spot of the laser light is such that at least a part of the corner portion along each of the above parts is heated to a temperature higher than that of the other parts to be softened and chamfered. It is disclosed.

Further, Japanese Patent Laid-Open No. 2-48423 discloses a chamfering method characterized in that the vicinity of the glass substrate including the ridge portion is locally heated by laser light to solidify the ridge portion into an R shape. There is. This is a method of chamfering a glass edge with so-called laser light.

However, in the above-mentioned chamfering method,
There are the following problems. That is, when a normal laser beam is applied to the glass end face as it is, the processing degree is different between the center part of the end face and the edge part.

Therefore, the above-mentioned Japanese Patent No. 261233.
In the method of processing the edge of the glass substrate disclosed in No. 2,
The laser beam was irradiated with the edge portion to be polished facing forward. Further, in the above-mentioned JP-A-2-48423, when the laser beam is irradiated from the front of the end face of the glass substrate, the spot diameter of the laser beam is made large, and a substance that absorbs the laser beam is applied only to a target portion, Trying to melt the target part.

By the way, in a normal laser beam,
The intensity distribution is generally Gaussian distribution.
The intensity distribution is schematically shown in FIG. In the figure, the vertical axis represents relative intensity.

Techniques for controlling the intensity distribution of this laser beam have been proposed. For example, JP-A-6-182574
In the issue, "Laser processing machine that homogenizes the intensity distribution of the laser beam emitted from the laser oscillator and irradiates the workpiece"
It is shown. As a means for "uniformizing the intensity distribution of the laser beam", "a kaleidoscope in which four strip-shaped reflecting mirrors are opposed to each other to form a regular quadrangular prism" is shown.

FIG. 1 and FIG. 4 shown in Japanese Patent Laid-Open No. 6-182574 (in this specification, FIG. 7A and FIG.
It is shown in (b). It should be noted that the reference numerals have been reassigned), according to the laser beam 110 from the laser oscillator 100.
Is incident on the kaleidoscope 320, which is the beam intensity converting means 300, via the phase distribution plate 200 rotated by the rotating mechanism 220. Further imaging lens 400
The image is reduced and imaged on the workpiece 500. Judging from the drawings, it is considered that the laser beam 110 and the beam intensity conversion means 300 are arranged on the same optical axis.

In addition to this, Japanese Patent Laid-Open No. 10-153750,
JP-A-10-323787, JP-A 2001-1212
82 and Japanese Patent Application Laid-Open No. 2001-1225040 disclose a technique using a lens as a means for making the intensity distribution of a laser beam uniform.

[0012]

If the above-mentioned "kaleidoscope" or lens is used as a means for making the intensity distribution of the laser beam uniform, the device becomes complicated and expensive.

Therefore, the present invention uses a laser generating device, a laser generating method, and a laser capable of converting the intensity distribution of a laser beam by an intensity distribution converting mechanism having a simple structure that does not use a "kaleidoscope" or a lens. A processing method is provided.

[0014]

In order to solve the above-mentioned problems, according to the present invention, the intensity distribution of a laser beam emitted from a laser oscillator is converted by an intensity distribution conversion mechanism composed of simple components. It has a feature.

Specifically, the emitted laser beam is
It is characterized in that the laser beam is incident on a pipe having an inner surface capable of reflecting the laser beam to convert its intensity distribution.

That is, in the first aspect of the present invention, the invention of claim 1 provides a laser generator comprising a laser oscillator and an intensity distribution conversion mechanism capable of leveling the intensity distribution of a laser beam from the laser oscillator. The intensity distribution conversion mechanism is a cylindrical body having an inner surface capable of reflecting the laser beam, and the laser beam from the laser oscillator is incident on the inside of the cylindrical body at a predetermined incident angle to convert the intensity distribution. The laser generator is characterized in that

According to a second aspect of the present invention, in the laser generator according to the first aspect, the cylindrical body is a laser generator which is a metal pipe.

As the invention of claim 3, claim 1 or 2
In the laser generator described in the above, the length and inner diameter of the tubular body, and the incidence, such that the laser beam incident on the tubular body has a predetermined number of reflections on the inner surface of the tubular body. It is a laser generator in which the angle is set.

According to a fourth aspect of the present invention, in the laser generator according to any one of the first to third aspects, the length and inner diameter of the cylindrical body are set so that the number of reflections is 5 to 18 times, and It is a laser generator in which the incident angle is set.

According to a fifth aspect of the present invention, in the laser generator according to any one of the first to fourth aspects, the intensity distribution conversion mechanism has a maximum intensity of the laser beam emitted from the laser oscillator. Imax, where Imin is the minimum strength that can cause a given change in the workpiece, Imax / I
It is a laser generator that can convert min to 1.33 or less.

According to a sixth aspect of the present invention, the laser generator according to any one of the first to fifth aspects further comprises a lens for making the laser beam emitted from the laser oscillator have a predetermined beam diameter. Laser generator.

According to a seventh aspect of the present invention, in the laser generator according to any one of the first to sixth aspects, a lens is further provided for making the laser beam emitted from the cylindrical body have a predetermined beam diameter. It is a laser generator provided.

According to an eighth aspect of the invention, there is provided the laser generator according to any one of the first to seventh aspects, further comprising a mechanism for cooling the cylindrical body.

According to a second aspect of the present invention, the invention of claim 9 provides a laser generating method characterized in that the intensity distribution of a laser beam emitted from a laser oscillator is leveled through an intensity distribution conversion mechanism. The intensity distribution conversion mechanism is characterized in that the laser beam from the laser oscillator is injected into a cylindrical body having an inner surface capable of reflecting the laser beam to convert the intensity distribution. Is.

According to a third aspect of the present invention, as the invention of claim 10, a laser beam emitted from a laser oscillator is leveled in intensity distribution of the laser beam through an intensity distribution conversion mechanism, and the laser beam is covered. In the processing method using a laser for irradiating a processing member, the intensity distribution conversion mechanism allows a laser beam from the laser oscillator to be incident inside a cylindrical body having an inner surface capable of reflecting the laser beam, This is a processing method using a laser characterized by performing distribution conversion.

The laser beam emitted from the ordinary laser has a Gaussian distribution as described above (see FIG. 4B). On the other hand, the present invention is characterized in that the intensity peak of the laser beam from the laser oscillator is suppressed by passing through the intensity distribution conversion mechanism, and the intensity distribution is leveled.

Specifically, the cross-sectional shape of the intensity distribution of the laser beam emitted from the intensity distribution conversion mechanism has a caldera shape. The intensity distribution is schematically shown in FIG. In the figure, the vertical axis represents relative intensity. As is clear from the comparison between (a) and (b) of FIG. 4, it is understood that the laser beam emitted from the intensity distribution conversion mechanism according to the present invention has its intensity distribution leveled.

In the present specification, a laser beam having such a pattern is referred to as a laser beam having a caldera-like intensity distribution, and may be abbreviated as a caldera-like distribution laser. Furthermore, such an intensity distribution is called a caldera-like distribution.

In this specification, the intensity distribution of the laser beam is confirmed by the following method. That is,
The laser beam emitted from the laser oscillator 1 is a pipe 3
The laser beam that is incident on and is emitted from the pipe 3.
By irradiating the thick paper 51 at a certain distance from the emission port of the pipe to make it brown, it is possible to collect the intensity distribution pattern 13 of the beam. The situation is shown in FIG. As a result, an example of the collected pattern is shown in FIG.

The intensity distribution conversion mechanism of the present invention is
Of the intensity distribution of the laser beam emitted from the laser oscillator, when Imax is the maximum intensity and Imin is the minimum intensity that can cause a predetermined change in the workpiece, Imax / Imin is 1.3.
It is preferably one that can be converted to 3 or less.

This Imin is the minimum strength capable of causing a predetermined change in the workpiece, and may be, for example, an energy strength capable of locally melting a brittle material (glass, ceramics).

When Imax / Imin is set to 1.33 or less, it means that the intensity distribution of the laser beam is sufficiently leveled when a predetermined change occurs in the workpiece. Therefore, a predetermined change in the object to be processed is leveled, which is a preferred embodiment. Further, FIGS. 4A and 4B show the range where Imax / Imin is 1.33 or less. As is clear from the figure, in the laser beam obtained by the laser generator of the present invention, the leveled beam intensity region is wider than in the Gaussian distribution laser beam.

In the laser generator of the present invention, it is preferable that the laser generator further comprises a lens for making the laser beam emitted from the laser oscillator have a predetermined beam diameter. Specifically, a lens for converging the emitted laser beam so that it can be effectively incident on the opening portion of the pipe may be provided.

The present invention provides a laser generator, a laser generating method, and a processing method using the same, which can eliminate unevenness in the degree of processing in chamfering an end surface of a brittle material, for example.

According to the present invention, the above-mentioned Japanese Patent No. 26
As in the method disclosed in No. 12332, the edge portion to be polished can be processed into an R shape by irradiating the end surface of the glass substrate from the front without irradiating the laser beam with the edge portion to be polished as the front surface. .

The laser beam that has passed through the inside of the pipe travels while increasing its diameter from the emission port of the pipe. Therefore, in the laser generator of the present invention, it is preferable that the laser beam emitted from the pipe is adjusted by the lens so that the laser beam has an appropriate beam diameter for the processing target.

The laser used in the present invention is preferably a carbon dioxide laser. When the object to be processed is glass, the temperature at the time of processing is set to the softening point of the glass or lower.

As the material of the pipe that serves as the intensity distribution conversion mechanism, it is preferable to use a material that does not absorb the energy of the laser beam as much as possible. Specifically, stainless steel, brass,
When a material such as copper that absorbs the energy of the laser beam is used, the energy emitted is greatly reduced with respect to the energy input. In order not to reduce the output efficiency, it is preferable to apply a reflective film such as gold plating on the inner surface of the pipe to improve the reflectance. Furthermore, it is desirable that the inner surface of the pipe be smooth in order to improve the reflectance.

When a laser oscillator with a large output is used, there is a fear that the pipe absorbs the energy of the laser beam and melts. In such a case, a cooling coil connected to the cooling device may be provided around the pipe. Further, the pipe may be provided with cooling fins for heat dissipation.

The conditions for installing the above-mentioned pipe are as follows: the laser beam is obliquely incident on the pipe at a predetermined incident angle so that the intensity distribution of the laser beam emitted from the pipe has a caldera shape. It is necessary to promote reflection diffusion.

In order to reflect and diffuse the laser beam inside the pipe, the incident angle (θ) needs to be θ> 0 degrees. On the other hand, the upper limit of the incident angle (θ) may be in the range where a caldera-shaped distributed laser can be efficiently obtained.
From Examples 1 and 2 described below, a preferable incident angle (θ) can be 20 degrees or less.

As a condition for the pipe, increasing the length of the pipe also promotes the reflection and diffusion inside the pipe.

Further, as a condition of the pipe, even if the inner diameter of the pipe is made small, the reflection and diffusion inside the pipe are promoted. When the entire laser beam cannot be made incident on the pipe by reducing the inner diameter of the pipe in this way, it is preferable to focus the laser beam with a lens.

Even if the inner surface of the pipe is coated with a reflective film such as gold plating, if the incident angle of the laser beam on the pipe is large, the energy will still be absorbed. Therefore, it is preferable that the incident angle is as small as possible within a range in which the laser beam is reflected and diffused inside the pipe to obtain a caldera-shaped distributed laser.

On the other hand, if the incident angle is too small, it is necessary to lengthen the pipe and there is a tendency that the device becomes large. According to Examples 1 and 2 described later, this incident angle (θ) is preferably 5 degrees or more.

Further, in order to obtain such a caldera-shaped distributed laser, the length, the inner diameter, and the incident angle of this cylindrical body are set in order to make the reflection within the cylindrical body a predetermined number of times. Good.

The specific number of reflections is preferably 5 to 18 times. Furthermore, 7 to 13 times is more preferable. further,
Most preferred is 9 to 10 times.

[0048]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A laser generator according to the present invention will be described with reference to the outline. FIG. 1 shows a schematic diagram of an apparatus for converting the intensity distribution of a laser beam. First, in FIG. 1, a laser beam is emitted from a laser oscillator 1.

The optical axis (A) of the laser beam is set at an angle θ with respect to the axis (B) of the pipe 3. FIG. 2 shows the details of the vicinity of the pipe entrance when the laser beam is made incident on the pipe 3.

The laser beam 11 emitted from the laser oscillator is incident on the pipe 3 installed at a predetermined angle. It is considered that the laser beam travels in the pipe 3 while being reflected as shown by the broken line in the figure.

At this time, when the beam diameter of the laser beam emitted from the laser oscillator 1 is larger than the inner diameter of the pipe, the emitted laser beam 11 is lensed so that all the laser beams 11 can enter the pipe. It is preferable that all the laser beams are made incident on the pipe 3 by condensing the laser beam by 2.

FIG. 3 shows details of the vicinity of the pipe emission port through which the laser beam is emitted from the pipe. The laser beam emitted from the pipe 3 has a caldera-like intensity distribution. After the laser beam is emitted from the pipe, it advances while expanding the beam diameter. Therefore, it is preferable to control the spread of this laser beam. For example, in order to adjust the beam diameter of the laser beam to an appropriate size for the processing surface shape of the target workpiece 5, the lens 4 is provided between the pipe 3 and the workpiece 5, and the laser beam 12 Adjust the beam diameter of.

Example 1 As a laser oscillator, Synrad
Laser was emitted at an output of 25 W using a model 48-1-28 manufactured by the company. This laser beam was made to enter the pipe through a lens of f = 1.5. Further, experiments were conducted by changing the incident angle of the laser beam on the pipe, the pipe length, and the distance from the pipe exit. The results are shown in Table 1. The distance between the laser oscillator and the pipe is 80 mm.
And

The angle of incidence on the pipe is varied within the range of 5 to 30 degrees, the pipe length is at two levels of 50 and 100 mm, the inner diameter of the pipe is 2 mm, and the distance from the pipe outlet is 1
There were two levels of 0 and 20 mm.

In Example 1, a brass pipe whose inner surface was plated with gold to improve the reflectance was used as the material of the pipe.

[0056]

[Table 1] ────────────────────────────────── Incident angle Pipe length Pipe inner diameter Distance Beam diameter (θ) (Mm) (mm) (mm) Inner diameter / outer diameter (mm) ─────────────────────────────── 5 100 2 20 2/6 10 100 2 20 4/8 15 100 2 20 9/13 20 100 2 20 11/14 25 100 2 20 − / − 30 30 100 2 20 − / − −−−−−−−−−−−−− −−−−−−−−−−−−−−−−−−−−−−− 5 100 2 10 0 / 3.5 10 100 2 10 1/5 15 15 100 2 10 6/9 20 1002 10 6/9 25 100 2 10 − / − 30 100 2 10 − / − −−−−−−−−−−−−−−−−−−−−−−−−− −−−−−−−−−− 5 50 2 20 − / − 10 50 2 20 − / − 15 50 2 20 9/14 20 50 50 2 20 11/18 25 50 2 20 − / − 30 30 50 2 20 − / −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−− 5 50 210 − / − 10 50 210 − / − 15 50 2 10 6/9 20 20 50 2 10 5/10 25 50 2 2 10 11/15 30 30 50 210-/-──────────────────────── ──────────── Pipe material: brass In addition, (-) in the table indicates that the irradiation pattern of the laser beam could not be sampled.

(Incident Angle to Pipe) From Table 1, it was found that the larger the incident angle of the laser beam, the larger the beam diameter after being emitted from the pipe.

Further, as the incident angle is increased, the ratio of the energy of the laser beam absorbed by the inner surface of the pipe increases. For this reason, the beam emission efficiency deteriorates, and when the incident angle is 25 degrees or more,
It became impossible to collect the pattern.

(Distance from Pipe Outlet) From Table 1, the distance from the pipe outlet to the irradiation position is 10 mm and 20 mm.
In comparison with the case of mm, it was found that the laser beam emitted from the pipe travels while expanding its beam diameter.

(Pipe Length) From Table 1, the pipe length is 1
In comparison between 00 mm and 50 mm, it was found that the longer the pipe, the more difficult it is to collect the pattern, and the larger the energy absorbed by the pipe. Here, it was found that the beam diameter does not depend on the length of the pipe.

Example 2 In this Example 2, a stainless steel pipe is used as it is as a pipe. The inner diameter of this pipe was 3.5 mm due to availability. The results are shown in Table 2. The distance between the laser oscillator and the pipe was 80 mm.

[0062]

[Table 2] ──────────────────────────────── Incident angle Pipe length Pipe inner diameter Distance Beam diameter (θ) (mm) ) (Mm) (mm) Inner diameter / outer diameter (mm) ────────────────────────────────── 5 100 3.5 20 − / − 10 100 3.5 3.5 20 − / − 15 100 100 3.5 20 − / − 20 100 100 3.5 20 − / − 25 100 3.5 3.5 20 14/22 −−−−−−−− −−−−−−−−−−−−−−−−−−−−−−−−−−− 5 50 3.5 10 − / − 10 50 3.5 3.5 10 − / − 15 50 3.5 10 − / − 20 50 3.5 3.5 10 − / − 25 50 3.5 3.5 10 5/12 ───────────────────────────── ────── Pipe material: stainless steel (-) in the table indicates that the irradiation pattern could not be collected.

As described above, comparing the results of Examples 1 and 2 (Tables 1 and 2), the brass pipe plated with gold to improve the reflectance shows the case where the stainless pipe is used as it is. It can be seen that the energy extraction efficiency is better and the pattern can be collected more easily. Further, the larger the inner diameter of the pipe, the larger the inner and outer diameters of the caldera-shaped portion of the beam, and the difference between the inner and outer diameters of the pattern is also the same.

It was found that the optimum condition range within the test range is a condition that the pipe length is 100 mm, the pipe inner diameter is 2 mm, and the incident angle of the laser beam is 5 to 20 degrees.

(Embodiment 3) When the angle of incidence on the pipe, the length of the pipe, and the distance from the outlet of the pipe were changed, the number of reflections in the pipe obtained geometrically and the pattern mode The results of comparison of sharpness are shown in Table 3. The inner diameter of the pipe was 2 mm.

[0066]

[Table 3] ───────────────────────────────   Incident angle Pipe length Number of reflections Sharpness of pattern     (Θ) L1 (mm) (times) L2: 10 mm 20 mm ────────────────────────────       5 100 4 ○ ×     10 100 9 ◎ △     15 100 13 ○ ○     20 100 18 △ ○     25 100 24 × × ---------------       5 502 2 × ×     10 50 4 × ×     15 50 7 △ △     20 50 9 △ ○     25 50 12 × △     30 50 14 ― △ ─────────────────────────────── ◎: clear caldera pattern, ○: caldera pattern, △: interrupted caldera pattern, ×: no caldera pattern, -: The pattern cannot be collected

From Table 3, it was found that the number of reflections in the pipe for confirming the intensity distribution of the beam was 5 to 18 times. That is, if the number of reflections is within this range, the intensity distribution can be leveled well, and energy absorption due to reflection in the pipe can be reduced.

It was also confirmed that a clear pattern could be obtained when the number of reflections was set to 7 to 13.

Further, assuming that the number of reflections is 9 to 10 times,
It was confirmed that a clearer pattern could be obtained.

Example 4 After chamfering a glass sample having two types of surface roughness described later with a laser oscillating with a Gaussian distribution and a laser having a caldera-like distribution according to the present invention. The results of measuring the surface roughness (Ra) are shown in Table 4. The unit is μm.

[0071]

[Table 4]   Surface roughness of glass (Ra; μm) ────────────────────────────                     # 500 Polished product Polished product ──────────────────────────── Before laser irradiation 0.54 0.12 −−−−−−−−−−−−−−−−−−−−−−−−− Energy distribution Gaussian distribution 0.12 0.08 Caldera-like distribution 0.07 --- ────────────────────────────

The # 500 polished product means that the end surface of the glass plate is 5
A sample polished with a No. 00 grindstone, and a polished product is a sample obtained by further polishing the sample with cerium oxide (Mirake 801 (trade name)).

From the results shown in Table 4, it was found that the surface roughness after chamfering was finer in the laser of caldera distribution than in the laser of Gaussian distribution.

(Reference Comparative Example) Japanese Patent Laid-Open No. 6-1825 mentioned above.
According to the technique disclosed in No. 74, in the laser generator of the first embodiment, a laser beam was made incident on the pipe at an incident angle of 0 degree. As a result, it was confirmed that the intensity distribution of the laser beam was a Gaussian distribution.

That is, in the present invention, the above-mentioned Japanese Patent Laid-Open No.
Even if the laser oscillator and the beam intensity converting means are linearly arranged with reference to the technique disclosed in Japanese Patent No. 182574, the intensity distribution of the laser beam could not be equalized.

The present invention has been described in detail above. Further, as a laser generating method which is the second embodiment of the present invention,
From the disclosure of the present specification, it can be understood as a form according to the laser generator.

The processing method using the laser beam according to the third embodiment of the present invention is understood as a processing method using the laser generating apparatus according to the first embodiment of the present invention or the laser generating method according to the second embodiment. be able to.

[0078]

As described above, the laser generator according to the present invention exhibits the effects described below. In the present invention, the intensity distribution of the laser beam can be converted with a simple configuration in which the laser beam is incident on the pipe. Therefore, the intensity distribution conversion mechanism can be realized with an inexpensive structure.

In this laser generator, the peak of the intensity distribution of the laser beam is lowered and leveled so that the object to be processed can be irradiated with the beam having the leveled beam intensity.

For this reason, it is possible to perform uniform and stable laser processing. For example, in chamfering the end face of a glass substrate, a laser beam can be irradiated from the front of the end face to chamfer the entire end face.

Further, for chamfering the end face of the glass plate with a Gaussian distribution laser, for example, the surface roughness after the process can be made fine.

[Brief description of drawings]

FIG. 1 is a diagram showing an outline of a laser beam generator according to the present invention.

FIG. 2 is a diagram showing how a laser beam is incident on a pipe for converting an intensity distribution.

FIG. 3 is a view showing a mechanism for adjusting a laser beam emitted from a pipe to an appropriate size for a surface shape to be processed by a lens.

FIG. 4 is a diagram showing an example of intensity distributions of a laser beam according to the present invention and a normal laser beam.

FIG. 5 is a diagram illustrating a manner of collecting an irradiation pattern of a laser beam.

FIG. 6 is a diagram showing an example of a laser beam irradiation pattern.

FIG. 7 is a diagram illustrating a configuration of a beam intensity conversion unit disclosed in Japanese Patent Laid-Open No. 6-182574.

[Explanation of symbols]

10: Laser generator 1: Laser oscillator 2: Lens 3: Cylindrical body (metal pipe) 4: Lens 5: Glass substrate 11, 12: Laser beam 13: Laser beam irradiation pattern 51: Cardboard A: Optical axis of laser beam emitted from laser oscillator B: Pipe axis L1: Pipe length L2: Distance between the pipe exit and the irradiation target f: lens focal length θ: Incident angle of laser beam

Claims (10)

[Claims] 1. A laser generator comprising a laser oscillator and an intensity distribution conversion mechanism capable of leveling the intensity distribution of a laser beam from the laser oscillator, wherein the intensity distribution conversion mechanism is capable of reflecting the laser beam. 1. A laser generator, which is a cylindrical body having a surface, wherein a laser beam from the laser oscillator is incident on the inside of the cylindrical body at a predetermined incident angle to perform intensity distribution conversion. 2. The laser generator according to claim 1, wherein the tubular body is a metal pipe. 3. The laser generator according to claim 1, wherein the laser beam incident on the tubular body has a predetermined number of reflections on the inner surface of the tubular body. A laser generator in which the body length and inner diameter and the incident angle are set. 4. The laser generator according to claim 1, wherein the length and the inner diameter of the tubular body and the incident angle are set such that the number of reflections is 5 to 18 times. Laser generator. 5. The laser generator according to claim 1, wherein the intensity distribution conversion mechanism has a maximum intensity Imax of a laser beam emitted from the laser oscillator and a workpiece. A laser generator capable of converting Imax / Imin to 1.33 or less, where Imin is the minimum intensity that can cause a predetermined change in the temperature. 6. The laser generator according to claim 1, further comprising a lens for making a laser beam emitted from the laser oscillator have a predetermined beam diameter. . 7. The laser generator according to claim 1, further comprising a lens for making a laser beam emitted from the cylindrical body have a predetermined beam diameter. apparatus. 8. The laser generator according to claim 1, further comprising a mechanism for cooling the tubular body. 9. A laser generation method characterized in that the intensity distribution of a laser beam emitted from a laser oscillator is leveled through an intensity distribution conversion mechanism, wherein the intensity distribution conversion mechanism is a laser from the laser oscillator. A laser generation method, characterized in that a beam is incident on the inside of a cylindrical body having an inner surface capable of reflecting the laser beam, and intensity distribution conversion is performed. 10. A processing method using a laser for irradiating a laser beam emitted from a laser oscillator with a laser beam for leveling the intensity distribution of the laser beam through an intensity distribution conversion mechanism and irradiating the laser beam onto a workpiece. The intensity distribution conversion mechanism uses a laser characterized in that a laser beam from the laser oscillator is incident on the inside of a cylindrical body having an inner surface capable of reflecting the laser beam to perform intensity distribution conversion. Method.