JPH07266071A - Laser beam machining device - Google Patents

Abstract

PURPOSE:To arbitrarily set a straight polarization direction at a laser beam machining point by transmitting a laser beam emitted from a laser beam oscillator without limiting the polarization state to a straight polarized light. CONSTITUTION:In order to transmit a laser beam 2 emitted from a laser beam oscillator 1 through an optical fiber 4, and to use the laser beam 2a being a random polarized light 5 emitted from the optical fiber 4, a laser beam polarization direction controlling means compared of a collimating lens 6 received inside a holder 20, a Brewster window 7, total reflection mirrors 8A to 8E and a condenser lens 10 is installed. Further, it consists of a rotary driving means in to rotate the holder 20 with gears 18, 19 using a servo motor 17 as a power source, the table device 11 to fix a material 16 to be machined and a controller 15 thereof. Therefore, the highly efficient laser beam machining can be flexibly executed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser processing apparatus for processing a material to be processed with a linearly polarized laser beam in which the linear polarization direction of the laser beam can be arbitrarily set.

[0002]

2. Description of the Related Art As a conventional laser processing apparatus capable of arbitrarily setting a polarization direction, for example, Japanese Patent Laid-Open No. 58-167 is available.
No. 86, JP-A-4-270091 is disclosed, but in any case, the laser beam emitted from the laser oscillator is limited to linearly polarized light, and the laser beam transmission is limited to the mirror transmission method.

[0003]

In the above-mentioned prior art,
The laser oscillator that can be used is limited to one that emits a linearly polarized laser beam, and the laser beam transmission is limited to the mirror transmission method, so the application range is narrow. Therefore, the present invention intends to solve these problems by providing a laser processing apparatus that can apply a transmission method using an optical fiber, which is a laser beam having an arbitrary polarization state.

[0004]

A laser beam transmitted from a laser oscillator by a mirror or an optical fiber is
A polarizing element that splits into two linearly polarized beams whose polarization planes are orthogonal to each other, and two linearly polarized beams that are split by the polarizing element have the same traveling direction and are arranged so that their polarization planes are parallel to each other. A rotation axis that brings about a rotationally symmetric relationship between a plurality of total reflection mirrors and two linearly polarized laser beams having the same traveling direction in the polarizing element and the plurality of total reflection mirrors and having parallel polarization planes. By configuring the polarizing element and the driving means for integrally rotating the plurality of total reflection mirrors around the center, it becomes possible to use a laser beam in any polarization state, and the optical fiber transmission method can be adopted. Flexible, efficient laser processing can be performed.

[0005]

The laser beam emitted from the laser oscillator is transmitted to a target position using an optical fiber. The collimator lens collimates the laser beam emitted from the emission end of the optical fiber while expanding it. The polarization state at this time is random polarization regardless of the polarization state of the laser beam emitted from the laser oscillator. Then, the collimated laser beam is split into two linearly polarized laser beams whose polarization planes are orthogonal to each other using a polarizing element.
Then, the two linearly polarized laser beams divided by the polarizing element are made to have the same traveling direction, and a plurality of total reflection mirrors are arranged so that their polarization planes are parallel to each other, and the traveling direction and the polarization direction are adjusted. To do. Then, the linear polarization direction is changed by integrally rotating the polarizing element and the plurality of total reflection mirrors about a rotation axis that provides a rotationally symmetrical relationship between the two adjusted linearly polarized laser beams. Can be done.

[0006]

FIG. 1 shows a first embodiment of the present invention. In FIG. 1, a laser beam 2 emitted from a laser oscillator 1 is incident on an optical fiber 4 by an optical fiber incidence lens 3. The laser beam 2 is transmitted by the optical fiber 4,
The collimator lens 6 collimates the laser beam 2A emitted while expanding from the emission end of the optical fiber 4. At this time, the laser beam 2A emitted from the optical fiber 4 is inevitably a randomly polarized light 5. The parallel polarized random polarization laser beam 2B is divided by the Brewster window 7 into two linear polarization laser beams (2C, 2D) whose polarization planes are orthogonal to each other, and have linear polarization directions 9A, 9B, respectively. Linearly polarized laser beam 2D
Is guided in the same direction as the linearly polarized laser beam 2C by a total reflection mirror (8A, 8B, 8C, 8D, 8E),
It also has a linear polarization direction 9G parallel to the polarization direction 9A. In FIG. 1, the polarization directions are on the same plane. Then, the linearly polarized laser beams (2C, 2I) whose polarization directions are aligned in parallel are condensed by the condenser lens 10, and the servo motors (13, 14) are constituted by the condensed linearly polarized laser beam 12.
The work material 16 fixed to the table 11 whose movement is controlled in an arbitrary direction is processed by the control device 15 using the as a driving source.

Further, a collimator lens 6, a Brewster window 7, and a total reflection mirror (8A to 8A) around a rotation axis Y that brings about a rotational symmetry relationship between two linearly polarized beams 2C and 2I whose traveling direction and polarization direction are adjusted. 8E), the holder 20 in which the condenser lens 10 is incorporated is rotated by the servomotor 17 via the gears 18 and 19 in response to a command from the control device 15 to collect the linearly polarized laser beam 12
By controlling the direction of linearly polarized light in the same direction as the direction of laser processing, highly efficient laser processing using linearly polarized light can be performed. At this time, total reflection mirror (8A-8E)
It is desirable to use one that does not lose its linearly polarized state. Further, the condenser lens 10 may be provided outside the holder 20, and if the center of the condenser lens 10 and the rotation axis Y coincide with each other, it is not necessary to rotate the condenser lens 10.

FIG. 2 shows an embodiment by mirror transmission as a second embodiment. The laser beam 2 emitted from the laser oscillator 1 is guided to the total reflection mirrors (8G, 8H) provided in the holder 20 via the total reflection mirror 8F. At this time, the polarization state of the laser beam 2 emitted from the laser oscillator 1 is not limited to linear polarization, and may be any polarization state. Then, the light is guided from the total reflection mirror 8H to the Brewster window 7, divided into two linearly polarized laser beams (2C, 2D) whose polarization planes are orthogonal to each other, and each has a linearly polarized direction (9A, 9B). The linearly polarized laser beam 2D is a total reflection mirror (8A, 8B, 8C, 8
D, 8E) is guided in the same direction as the linearly polarized laser beam 2C and is parallel to the polarizing direction 9A.
Have G. In FIG. 2, the polarization directions (9A, 9G) are on the same plane. The polarization direction (9
A, 9G) are linearly polarized laser beams (2
C, 2I) is condensed, and the material 16 to be processed can be processed by the condensed linearly polarized laser beam 12.

Further, with respect to the axis at which the optical axis of the laser beam 2A and the rotation axis Y which bring about a rotational symmetry relationship between the two linearly polarized laser beams (2C, 2I) whose traveling direction and polarization direction are adjusted, The controller 20 includes a holder 20 in which the total reflection mirrors (8G, 8H), the Brewster window 7, the total reflection mirrors (8A to 8E), and the condenser lens 10 are incorporated.
In response to a command from 5, the servomotor 17 rotates the gear (18,
19), the linearly polarized laser beam 12 that has been condensed is controlled so that the linearly polarized direction (9A, 9G) of the condensed linearly polarized laser beam 12 coincides with the direction in which laser processing is performed. Laser processing can be performed.

In the embodiment of the present invention, the gear (1
8 and 19), the rotation driving means such as a cylinder whose rotational position can be controlled may be replaced.

Further, in the embodiment of the present invention, the material 16 to be processed is used.
Although the method of moving the fixed table 11 by moving the laser beam 12 is also possible, a method of moving the laser beam 12 or a method of moving both the laser beam 12 and the table 11 is also possible.

[0012]

According to the present invention, the laser beam emitted from the laser oscillator is not limited to linearly polarized light, and a laser beam having any polarization state can be used. Further, since a laser beam transmission system using an optical fiber can be adopted, highly efficient laser processing using linearly polarized light can be flexibly performed.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a main part of a first embodiment of the present invention.

FIG. 2 is a diagram showing a configuration of a main part of a second embodiment of the present invention.

[Explanation of symbols]

1 is a laser oscillator, 2, 2A, 2B, 2C, 2D, 2
E, 2F, 2G, 2H, 2I are laser beams, 3 is an optical fiber entrance lens, 4 is an optical fiber, 5 is random polarization, 6 is a collimating lens, 7 is a Brewster window, 8A, 8B, 8C, 8D, 8E, 8F, 8G, 8H
Is a total reflection mirror, 9A, 9B, 9C, 9D, 9E, 9
F and 9G are linear polarization directions, 10 is a condenser lens, 11 is a table, 12 is a linearly polarized laser beam, 13, 14, and 1.
Reference numeral 7 is a servo motor, 15 is a control device, 16 is a material to be processed, 18 and 19 are gears, 20 is a holder, and Y is a rotary shaft.

Claims (1)

[Claims] 1. A laser processing apparatus for processing a material to be processed by emitting a laser beam, wherein a randomly polarized laser beam transmitted from a laser oscillator is divided into two linearly polarized laser beams whose polarization planes are orthogonal to each other. The polarizing element, a plurality of total reflection mirrors arranged such that the two linearly polarized laser beams divided by the polarizing element have the same traveling direction and the polarization planes are parallel to each other; Two linearly polarized laser beams having the same traveling direction and parallel planes of polarization by a plurality of total reflection mirrors are rotated about the rotation axis that provides a rotationally symmetric relationship, and the polarizing element and the plurality of A laser processing device comprising a driving means for rotating a total reflection mirror integrally.