JP2010214382A - Laser shutter unit and laser beam machining apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To quickly change over a transmitting state of transmitting a laser beam emitted from a laser oscillator and an intercepting state of intercepting the laser beam. <P>SOLUTION: A laser shutter unit 1 changes over the transmitting state of transmitting a laser beam L emitted from a laser oscillator 20 and the intercepting state of intercepting the laser beam L. The laser shutter unit 1 includes a first reflection mirror 10a for reflecting a part of the laser beam L emitted from the laser oscillator 20 and with a second reflection mirror 10b for reflecting the remainder of the laser beam L. In the transmitting state, the first and the second reflection mirror 10a, 10b are situated in a position not reflecting the laser beam L. In the intercepting state, the first reflection mirror 10a is situated in a position reflecting a part of the laser beam L and the second reflection mirror 10b is situated in a position reflecting the remainder of the laser beam L. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a laser shutter unit that switches between a transmitting state that transmits laser light emitted from a laser oscillator and a blocking state that blocks the laser light, and a laser processing apparatus that uses such a laser shutter unit.

  Conventionally, a laser processing apparatus including a laser oscillator that irradiates laser light, a laser shutter unit that switches between a transmitting state that transmits the laser light irradiated from the laser oscillator and a blocking state that blocks the laser light. Is known (see Patent Documents 1 and 2).

In such a laser processing apparatus, when processing a target substrate such as a glass substrate, it is necessary to control the opening / closing timing of the laser shutter unit in accordance with the processing start timing and processing completion timing. This is because a predetermined time is required until the output of the laser beam emitted from the laser oscillator is stabilized, and the laser beam is blocked during this period. Also, when replacing the substrate to be processed, it is necessary to synchronize the laser processing apparatus with an external transfer machine in order to block the laser beam. In this sense, a laser shutter unit is necessary in the laser processing apparatus. It is an indispensable unit.
JP 2007-136478 A JP-A-6-196789

  However, in the conventional laser shutter unit, the time required for switching between the transmitting state and the blocking state (OPEN, CLOSE) by the laser shutter unit takes about 0.3 seconds due to a vibration problem and the like. For this reason, at the time of switching operation of the laser shutter unit, the laser beam is deformed or the laser beam is lost at the rise or fall of the laser oscillation, so that unstable processing is likely to occur.

  On the other hand, as a method of cutting out an unstable pulse generated in the early stage of pulsed laser oscillation, a method of high-speed shattering using an optical element such as an AO modulator is conceivable. There is a problem in that it cannot be controlled, and the beam distribution after passing through the AO modulator is disturbed, affecting processing.

  The present invention has been made in consideration of such points, and a laser shutter capable of quickly switching between a transmitting state for transmitting laser light emitted from a laser oscillator and a blocking state for blocking laser light. It is an object to provide a unit and a laser processing apparatus using such a laser shutter unit.

The laser shutter unit according to the present invention comprises:
In a laser shutter unit that switches between a transmitting state that transmits laser light emitted from a laser oscillator and a blocking state that blocks the laser light,
A first reflecting mirror capable of reflecting a part of the laser light emitted from the laser oscillator;
A second reflecting mirror capable of reflecting the remainder of the laser beam,
In the transmission state, the first reflection mirror and the second reflection mirror are positioned at positions that do not reflect the laser beam. In the blocking state, the first reflection mirror reflects a portion of the laser beam. And the second reflecting mirror is positioned to reflect the remainder of the laser beam.

In the laser shutter unit according to the present invention,
A first absorbing member that absorbs part of the laser light reflected by the first reflecting mirror;
It is preferable to further include a second absorbing member that absorbs the remaining part of the laser light reflected by the second reflecting mirror.

In the laser shutter unit according to the present invention,
A first rotation drive unit for rotating the first reflection mirror;
A second rotation drive unit for rotating the second reflection mirror;
In the transmission state, the first reflection mirror and the second reflection mirror are positioned substantially parallel to the laser beam, and in the blocking state, the first reflection mirror is rotated to reflect a part of the laser beam. Preferably, the second reflecting mirror is rotated and positioned at a position where the remaining part of the laser beam is reflected.

In the laser shutter unit according to the present invention,
A first rotation drive unit for rotating the first reflection mirror;
A second rotation drive unit for rotating the second reflection mirror;
In the transmission state, the first reflection mirror and the second reflection mirror are positioned substantially parallel to the laser beam, and in the blocking state, the first reflection mirror is rotated to reflect a part of the laser beam. The second reflecting mirror is rotated and positioned to reflect the remainder of the laser beam,
The first absorbing member has a substantially fan-shaped or elongated rectangular cross section in order to absorb laser light reflected when the first reflecting mirror rotates,
The second absorbing member preferably has a substantially fan-shaped or elongated rectangular shape in cross section in order to absorb laser light reflected when the second reflecting mirror rotates.

The laser processing apparatus according to the present invention comprises:
A laser oscillator for irradiating a laser beam;
A laser shutter unit that switches between a transmission state that transmits laser light emitted from the laser oscillator and a blocking state that blocks the laser light;
The laser shutter unit is
A first reflecting mirror capable of reflecting a part of the laser light emitted from the laser oscillator;
A second reflecting mirror capable of reflecting the remainder of the laser beam,
In the transmission state, the first reflection mirror and the second reflection mirror are positioned at positions that do not reflect the laser beam. In the blocking state, the first reflection mirror reflects a portion of the laser beam. And the second reflecting mirror is positioned to reflect the remainder of the laser beam.

  According to the present invention, in the transmission state, the first reflection mirror and the second reflection mirror are positioned at positions that do not reflect the laser beam, while in the blocking state, the first reflection mirror reflects a part of the laser beam. The second reflection mirror is positioned at a position where the remaining part of the laser beam is reflected. For this reason, it is possible to quickly switch between a transmission state in which the laser beam emitted from the laser oscillator is transmitted and a blocking state in which the laser beam is blocked.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a laser shutter unit and a laser processing apparatus according to the present invention will be described below with reference to the drawings. Here, FIG. 1 to FIG. 3 are diagrams showing an embodiment of the present invention.

  As shown in FIG. 1, the laser processing apparatus according to the present embodiment includes a laser oscillator 20 that irradiates laser light L, and an optical path changing reflection mirror that reflects the laser light L emitted from the laser oscillator 20 and changes the optical path. (Total reflection mirror) 25, and a laser shutter unit 1 that switches between a transmission state in which the laser beam L emitted from the laser oscillator 20 is transmitted and a blocking state in which the laser beam L is blocked.

  Among these, as shown in FIG. 1, the laser shutter unit 1 is disposed so as to be rotatable around a rotation shaft 11a, and can reflect a part of the laser light L emitted from the laser oscillator 20, and can reflect the first reflection mirror 10a. A second reflection mirror 10b that is arranged to be rotatable about the rotation shaft 11b and that can reflect the remaining part of the laser light L (the laser light L that has not been reflected by the first reflection mirror 10a), and the first reflection mirror 10a. And a second rotation drive unit (second drive unit) 15b for rotating the second reflecting mirror 10b.

  In the present embodiment, description will be made using the first reflecting mirror 10a and the second reflecting mirror 10b that are rotatable. However, the present invention is not limited to this. For example, the first reflecting mirror 10a slides to cause laser light. It is also possible to use a mode in which a part of L is reflected and the remaining part of the laser beam L is reflected by the second reflecting mirror 10b sliding similarly. However, it is possible to switch between the transmission state and the blocking state with a slight rotation. Therefore, from the point that the transmission state and the blocking state can be switched quickly, the first reflection mirror 10a as shown in the present embodiment. It is preferable to use a mode in which the second reflecting mirror 10b is rotated.

  By the way, in the transmission state, the first reflection mirror 10a and the second reflection mirror 10b are configured to be positioned at positions where the laser light L is not reflected (see FIG. 1). More specifically, in the present embodiment, the first reflection mirror 10a and the second reflection mirror 10b are configured to be positioned substantially parallel to the laser beam L in the transmission state.

  On the other hand, in the cut-off state, the first reflection mirror 10a is positioned at a position where a part of the laser light L is reflected, and the second reflection mirror 10b is positioned at a position where the remaining part of the laser light L is reflected. (See FIG. 2). More specifically, in the present embodiment, in the cut-off state, the first reflection mirror 10a is rotated and positioned at a position where a part of the laser beam L is reflected, and the second reflection mirror 10b is rotated and the laser beam is rotated. It is configured to be positioned at a position where the remainder of L is reflected.

  As shown in FIG. 1, the laser shutter unit 1 includes a first absorbing member 30a that absorbs part of the laser light L reflected by the first reflecting mirror 10a and a laser that is reflected by the second reflecting mirror 10b. A second absorbing member 30b that absorbs the remainder of the light L is further provided. Among these, the 1st cooling device 35a which cools the said 1st absorption member 30a is provided in the 1st absorption member 30a, and the 2nd cooling device which cools the said 2nd absorption member 30b in the 2nd absorption member 30b. 35b is provided. As the first absorbing member 30a and the second absorbing member 30b, for example, a damper that multi-reflects the laser light L can be used.

  In the present embodiment, in order to absorb the laser light L reflected when the first reflecting mirror 10a rotates, the first absorbing member 30a has a substantially fan-shaped cross section. In order to absorb the laser beam L reflected when the two-reflection mirror 10b rotates, the second absorption member 30b has a substantially fan-shaped cross section. Accordingly, in the present embodiment, the first cooling device 35a and the second cooling device 35b are also substantially fan-shaped in cross section. By the way, the 1st absorption member 30a and the 2nd reflective mirror 10b should just consist of a shape which absorbs the laser beam L reflected when the 1st reflective mirror 10a and the 2nd reflective mirror 10b rotate, and the above-mentioned. As described above, the cross section may not be substantially fan-shaped, but the cross section may be, for example, an elongated rectangular shape extending along the traveling direction of the laser light L.

  As the laser oscillator 20, for example, a pulse laser oscillator that emits a pulse laser or a CW laser oscillator that emits a CW laser can be used. The present invention can produce a more beneficial effect when the laser oscillator 20 emits a laser beam L having a large diameter (for example, a laser beam L having a diameter of 10 mm or more). A description will be given using a mode in which a laser beam L having a large diameter is irradiated from the laser oscillator 20 (see FIGS. 1 and 2).

  As shown in FIG. 1, the laser processing apparatus according to this embodiment has a holding moving unit 40 that holds a substrate to be processed 60 such as a glass substrate processed by the laser light L reflected by the optical path changing reflection mirror 25. It has. The holding / moving unit 40 can hold the substrate 60 to be moved in the horizontal direction and the θ direction. By the way, in the present embodiment, a description will be given using a mode in which the holding and moving unit 40 holds the substrate 60 to be moved in the horizontal direction and the θ direction. However, the present invention is not limited to this. The aspect which moves 60 only to a horizontal direction may be sufficient, and the aspect which moves the to-be-processed substrate 60 only to (theta) direction may be sufficient.

  Further, as shown in FIG. 1, the laser oscillator 20, the first rotation driving unit 15 a, the second rotation driving unit 15 b, and the holding and moving unit 40 are electrically connected to a control unit 50 that controls them. Yes. In the present embodiment, description is made using the configuration shown in FIG. 1, but the present invention is not limited to this. For example, the optical path changing reflection mirror 25 may not be provided, and the optical path changing reflection mirror 25 may be positioned on the rear side (processing side) of the first reflection mirror 10a and the second reflection mirror 10b. Furthermore, a condensing lens that condenses the laser light L may be provided, or the laser light that has passed through the condensing lens may be guided into the optical fiber and transmitted through the fiber.

  In the present embodiment, the first reflecting mirror 10a and the second reflecting mirror 10b will be described using flat plates, but the present invention is not limited to this, and the direction different from the irradiation path when shut off For example, a polygonal mirror such as a polygon mirror can be used as the first reflection mirror and the second reflection mirror. A mirror or a curved mirror such as a cylindrical inner surface can also be used. In addition, by adjusting the mirror surfaces of the polygon mirror and the curved mirror, even if the optical path is changed when the first reflecting mirror and the second reflecting mirror are rotated, the arrival position of the laser beam L is made one place. It can concentrate, and the magnitude | size of the 1st absorption member 30a and the 2nd absorption member 30b can be made small.

  Next, the operation of the present embodiment having such a configuration will be described.

Transmission state First, a case where the laser beam L irradiated from the laser oscillator 20 is transmitted will be described.

  First, the laser beam L is emitted from the laser oscillator 20. At this time, the laser oscillator 20 emits laser light L having a large diameter (for example, laser light L having a diameter of 10 mm or more) (see FIG. 1).

  Next, the laser beam L emitted from the laser oscillator 20 is reflected by the optical path changing reflection mirror 25 to change the optical path (see FIG. 1).

  Next, the laser beam L reflected by the optical path changing reflection mirror 25 passes through the laser shutter unit 1 and reaches the substrate 60 to be processed held by the holding and moving unit 40, thereby the substrate to be processed 60 is processed (see FIG. 1). The holding and moving unit 40 adjusts the processing position of the substrate 60 to be processed by moving the substrate 60 to be processed in the horizontal direction and the θ direction.

  Thus, when the laser beam L passes through the laser shutter unit 1, each of the first reflection mirror 10a and the second reflection mirror 10b is positioned substantially parallel to the laser beam L and does not reflect the laser beam L. Is positioned (see FIG. 1).

Blocked state will now be described a case that is the cut-off state in which the laser beam L emitted from the laser oscillator 20.

  Based on the signal from the control unit 50, the first rotation drive unit 15a rotates the first reflection mirror 10a around the rotation axis 11a, and the laser beam L emitted from the laser oscillator 20 by the first reflection mirror 10a. (In this embodiment, the right part of FIG. 2 of the laser light L) is reflected (see FIG. 2). At this time, similarly, based on the signal from the control unit 50, the second rotation drive unit 15b drives the second reflection mirror 10b to rotate about the rotation axis 11b, and the second reflection mirror 10b causes the laser light L to be rotated. The remaining part (the laser light L that has not been reflected by the first reflecting mirror 10a, in this embodiment, the left part of FIG. 2 in the laser light L) is reflected (see FIG. 2).

  As described above, according to the present embodiment, a part of the laser light L emitted from the laser oscillator 20 is reflected by the first reflecting mirror 10a, while the remaining part of the laser light L emitted from the laser oscillator 20 is reflected. Since the light is reflected by the second reflecting mirror 10b, the laser light L reaching the substrate 60 can be blocked by simply rotating the reflecting mirrors 10a and 10b by a slight angle. For this reason, the transmission state and the blocking state can be quickly switched. For example, even with the laser light L having a diameter of 10 mm, the transmission state and the blocking state can be switched quickly with a response speed of 5 ms or less.

  In this regard, even when a single reflection mirror is used, the angle of rotation of the reflection mirror can be reduced by increasing the size of the reflection mirror, which can be used to quickly switch between the transmission state and the cutoff state. . However, increasing the size of the reflecting mirror is not preferable because the load applied to the rotary drive unit increases. In the present embodiment, by using two reflection mirrors 10a and 10b having the same size (large size), the transmission state and the blocking state can be switched more quickly.

  Further, the laser oscillator 20 is moved so as to cross the front surface of the portion to be irradiated with the laser light L (by moving in a direction perpendicular to the traveling direction of the laser light L) to cut off between the transmitting state and the blocking state. It is conceivable to provide a plate (not shown), but with such a blocking plate, reflection of the laser light L toward the laser oscillator 20 is inevitably generated, and the laser oscillator 20 may be damaged. It is not preferable. In addition, when such a blocking plate is provided, a cooling mechanism for cooling the blocking plate is required. However, when such a cooling mechanism is provided, the size becomes large and it is difficult to drive at high speed.

  In this respect, according to the present embodiment, there is no possibility of damaging the laser oscillator 20 without applying an excessive load to the rotation driving units 15a and 15b, and the configuration of the apparatus becomes complicated or large. This is preferable because the transmission state and the blocking state can be quickly switched without causing trouble.

  Further, according to the present embodiment, since the transmission state and the cutoff state can be quickly switched as described above, the laser light L is continuously or continuously irradiated from the laser oscillator 20 in the state where the laser is continuously emitted. By switching between the transmitting state and the blocking state by the shutter unit 1, the irradiation of the laser beam L to the substrate 60 can be controlled.

  Therefore, conventionally, for example, when the laser oscillation is restarted after the laser oscillation of the laser oscillator 20 is stopped while the workpiece substrate 60 is replaced, the laser light L reaches a predetermined output. Where it is necessary to throw a discard pulse, according to the present embodiment, since the substrate to be processed 60 can be processed with laser light having a predetermined output from the beginning, unstable processing portions can be eliminated. As a result, the substrate to be processed 60 can be processed with the laser light L having high processing stability, and the substrate to be processed 60 can be processed quickly and reliably. Note that according to the present embodiment, switching between the transmission state and the blocking state can be performed at high speed, so that the waveform of the laser light L can also be prevented from being deformed at the time of switching.

  As described above, part of the laser light L reflected by the first reflecting mirror 10a reaches the first absorbing member 30a and is absorbed by the first absorbing member 30a. On the other hand, the remaining part of the laser light L reflected by the second reflecting mirror 10b reaches the second absorbing member 30b and is absorbed by the second absorbing member 30b. Thus, although the 1st absorption member 30a and the 2nd absorption member 30b absorb the laser beam L, they will be heated, but the 1st absorption member 30a is cooled with the 1st cooling device 35a, and on the other hand Since the absorption member 30b is cooled by the second cooling device 35b, it is possible to prevent the first absorption member 30a and the second absorption member 30b from becoming excessively high in temperature.

  By the way, in the present embodiment, the laser shutter unit 1 has been described using an aspect having two reflection mirrors, the first reflection mirror 10a and the second reflection mirror 10b. However, the present invention is not limited to this, and FIG. As shown, the laser shutter unit 1 may have three or more reflecting mirrors (four reflecting mirrors in FIG. 3) (of course, it is not limited to four reflecting mirrors as shown in FIG. 3). And may have three reflecting mirrors, and may have five or more reflecting mirrors). In this case, one of them constitutes the first reflection mirror 10a, and one of the remaining mirrors constitutes the second reflection mirror 10b.

  In FIG. 3, reference numeral 10c denotes a third reflection mirror, reference numeral 10d denotes a fourth reflection mirror, reference numeral 15c denotes a third rotation drive unit, reference numeral 15d denotes a fourth rotation drive unit, and reference numeral 30c. Indicates a third absorbing member, reference numeral 30d indicates a fourth absorbing member, reference numeral 35c indicates a third cooling device, and reference numeral 35d indicates a fourth cooling device.

  Incidentally, in FIG. 3, a part of the laser light L emitted from the laser oscillator 20 by the first reflecting mirror 10a (in the present embodiment, the part on the right side of FIG. ) Is reflected, and a part of the remaining part of the laser beam L irradiated from the laser oscillator 20 by the third reflecting mirror 10c (in the present embodiment, the right side of FIG. Part) is reflected, and the second reflection mirror 10b reflects a part of the remaining part of the laser light L (in this embodiment, the part on the left side of FIG. The remaining part of the laser beam L is reflected by the fourth reflecting mirror 10d (in this embodiment, the portion of the laser beam L on the left side in FIG. 3 and on the front side of the sheet).

  As shown in FIG. 3, when three or more reflecting mirrors 10a-10d are used, the laser beam L having a larger diameter can be blocked without imposing a large load on the rotation driving units 15a-15d. It becomes like this. On the other hand, for the laser beam L having the same diameter, the laser beam L can be shielded by a smaller reflecting mirror, so that the inertial force for driving the reflecting mirror can be reduced. It can be switched more quickly, or a low-power drive source (such as a small motor) can be used.

Schematic which shows the aspect in which the laser processing apparatus by embodiment of this invention exists in a permeation | transmission state. Schematic which shows the aspect which the laser processing apparatus by embodiment of this invention exists in the interruption | blocking state. Schematic which shows the aspect in which the laser processing apparatus by the modification of embodiment of this invention is in the interruption | blocking state.

DESCRIPTION OF SYMBOLS 1 Laser shutter unit 10a 1st reflection mirror 10b 2nd reflection mirror 11a, 11b Rotating shaft 15a 1st rotation drive part (1st drive part)
15b Second rotation drive unit (second drive unit)
20 Laser oscillator 25 Optical path changing reflection mirror (total reflection mirror)
26 half mirror 30a first absorbing member 30b second absorbing member 35a first cooling device 35b second cooling device 40 holding and moving part 60 substrate to be processed L laser light

Claims (5)

In a laser shutter unit that switches between a transmitting state that transmits laser light emitted from a laser oscillator and a blocking state that blocks the laser light,
A first reflecting mirror capable of reflecting a part of the laser light emitted from the laser oscillator;
A second reflecting mirror capable of reflecting the remainder of the laser beam,
In the transmission state, the first reflection mirror and the second reflection mirror are positioned at positions that do not reflect the laser beam. In the blocking state, the first reflection mirror reflects a portion of the laser beam. The laser shutter unit is characterized in that the second reflection mirror is positioned to reflect the remaining part of the laser beam. A first absorbing member that absorbs part of the laser light reflected by the first reflecting mirror;
The laser shutter unit according to claim 1, further comprising a second absorbing member that absorbs a remaining portion of the laser light reflected by the second reflecting mirror. A first rotation drive unit for rotating the first reflection mirror;
A second rotation drive unit for rotating the second reflection mirror;
In the transmission state, the first reflection mirror and the second reflection mirror are positioned substantially parallel to the laser beam, and in the blocking state, the first reflection mirror is rotated to reflect a part of the laser beam. 3. The laser shutter unit according to claim 1, wherein the second reflection mirror is positioned at a position where the second reflection mirror is rotated to reflect the remaining part of the laser light. 4. A first rotation drive unit for rotating the first reflection mirror;
A second rotation drive unit for rotating the second reflection mirror;
In the transmission state, the first reflection mirror and the second reflection mirror are positioned substantially parallel to the laser beam, and in the blocking state, the first reflection mirror is rotated to reflect a part of the laser beam. The second reflecting mirror is rotated and positioned to reflect the remainder of the laser beam,
The first absorbing member has a substantially fan-shaped or elongated rectangular cross section in order to absorb laser light reflected when the first reflecting mirror rotates,
3. The second absorbing member according to claim 2, wherein the second absorbing member has a substantially fan-shaped or elongated rectangular shape in cross section so as to absorb laser light reflected when the second reflecting mirror rotates. The laser shutter unit described. A laser oscillator for irradiating a laser beam;
A laser shutter unit that switches between a transmission state that transmits laser light emitted from the laser oscillator and a blocking state that blocks the laser light;
The laser shutter unit is
A first reflecting mirror capable of reflecting a part of the laser light emitted from the laser oscillator;
A second reflecting mirror capable of reflecting the remainder of the laser beam,
In the transmission state, the first reflection mirror and the second reflection mirror are positioned at positions that do not reflect the laser beam. In the blocking state, the first reflection mirror reflects a portion of the laser beam. The laser processing apparatus is characterized in that the second reflection mirror is positioned at a position where the remaining part of the laser beam is reflected.

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