JP2005230872A - Laser beam machine and laser beam machining method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a multi-beam laser beam machine capable of performing machining by single beams for high-energy machining without increasing the output of a laser oscillator and machining by multi-beams for highly-efficient machining by switching both machining in a simple manner. <P>SOLUTION: The laser beam machine is provided with: a quarter-wave plate 20; a driving device 21 to insert/pull out the quarter-wave plate 20 in/from an optical path of laser beams 2 from a laser oscillator 1 to a first polarized beam splitter 7; and a control device 22 to control the driving device 21. The quarter-wave plate 20 is adequately arranged so as to change the polarized beam state of the laser beams 2 from the linearly polarized beam to the circularly polarized beam when inserted on the optical path of the laser beams 2. The laser beams 2 emitted from the laser oscillator 1 are adjusted so that the polarizing direction is set to be the same direction as that of P-wave transmitted through the first polarized beam splitter 7 by the linearly polarized beam. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a laser processing machine and a processing method having a function of easily switching between multi-beam processing and single beam processing in a short time by switching the polarization of a laser beam incident on a polarization beam splitter.

  FIG. 7 shows a multi-beam laser processing in which one laser beam is split into two laser beams by a polarizing beam splitter for spectroscopy, and the two laser beams are independently scanned to perform processing at two locations simultaneously. It is a schematic block diagram which shows a machine (for example, refer patent document 1).

International Publication No. WO03 / 041904 (pages 7-9, FIG. 1)

FIG. 7 shows a conventional multi-beam laser processing machine. In FIG. 7, 1 is a laser oscillator, 2 is a laser beam emitted from the laser oscillator 1, 2a is a polarization direction of the laser beam 2 adjusted to 45 degrees, and 4 is incident to make a machining hole into a desired machining shape. This is a mask for cutting out a necessary portion of the laser beam from the laser beam to be processed.
Reference numeral 7 denotes a first polarizing beam splitter for splitting the laser beam 2 into two laser beams, 8 denotes a laser beam transmitted through the first polarizing beam splitter 7, 8a denotes a polarization direction of the laser beam 8, and 9 denotes a first beam. The laser beam reflected from one polarization beam splitter 7, the polarization direction of the laser beam 9, 10 reflects the laser beam 8 and transmits the laser beam 9, so that both laser beams are mixed and led to substantially the same optical path. A second polarization beam splitter 11 for scanning is a first galvano scanner which is one type of scanner for scanning the laser beam 9 in two axial directions and guiding it to the second polarization beam splitter 10.
Reference numeral 12 denotes a plurality of bend mirrors that reflect the laser beam 2 and the laser beam 9 and guide them to the optical path, 13 denotes a workpiece, and 14 scans the laser beam 8 and the laser beam 9 in two directions to guide them to the workpiece 13. A second galvano scanner which is one type of the scanner, 15 a galvano scan area which is a range which can be scanned by the first galvano scanner 11 and the second galvano scanner 14, and 16 a laser beam 8, 9 which is a workpiece 13. An fθ lens 17 for condensing light in the upper galvano scan area 15 is an XY stage for moving the workpiece 13.
Note that the optical system from the bend mirror 12 to the second galvano scanner 14 immediately before the first polarizing beam splitter 7 may be collectively referred to as a multi-beam unit.

  Next, the operation will be described. The laser beam 2 emitted from the laser oscillator 1 is linearly polarized light whose polarization direction is adjusted to 45 degrees. Here, the polarization direction is adjusted to 45 degrees because the P wave (laser beam 8 in FIG. 7) that is transmitted through the first polarization beam splitter 7 and whose polarization direction is perpendicular to the incident surface, and the first The polarization beam is incident on the first polarization beam splitter 7 in a state where the polarization direction is inclined by 45 degrees with respect to the S wave (laser beam 9 in FIG. 7) whose reflection direction is parallel to the incident surface. This means that the polarization direction is adjusted. The laser beam 2 passes through the mask 4 so that an image for transferring a desired processed shape can be formed on the workpiece 13. The laser beam 2 that has passed through the mask 4 is transmitted through the first polarizing beam splitter 7 and reflected by the laser beam 8 whose polarization direction 8a is a P wave perpendicular to the incident surface and the first polarizing beam splitter 7 to be polarized. The direction 9a is split into a laser beam 9 which is an S wave parallel to the incident surface. Here, since the laser beam 2 is incident on the first polarization beam splitter 7 while being adjusted to a polarization direction of 45 degrees with respect to the P wave and the S wave, the laser beam 8 and the laser beam 9 have the same energy. Spectral as if to have.

  The laser beam 8 transmitted through the first polarizing beam splitter 7 is guided to the second polarizing beam splitter 10 via the bend mirror 12. On the other hand, the laser beam 9 reflected by the first polarizing beam splitter 7 is scanned in the biaxial direction by the first galvano scanner 11 and then guided to the second polarizing beam splitter 10. The laser beam 8 is always guided to the second polarization beam splitter 10 at the same position, but the laser beam 9 is transmitted to the second polarization beam splitter 10 by controlling the swing angle of the first galvano scanner 11. The incident position and angle are adjusted.

  Thereafter, the laser beam 8 is reflected by the second polarization splitter 10, and the laser beam 9 is transmitted by the second polarization beam splitter 10, so that both laser beams follow substantially the same optical path as the second galvanometer. Guided to the scanner 14. Then, after being scanned in the biaxial direction by the second galvano scanner 14, it is guided to the fθ lens 16, and is condensed at a predetermined position in the galvano scan area 15 on the workpiece 13 to perform processing. At this time, by scanning the first galvano scanner 11 and the second galvano scanner 14, the laser beams 8 and 9 are irradiated to any two different points in the galvano scan area 15 on the workpiece 13. Is possible. After the processing in the galvano scan area 15 is completed, the next galvano scan area can be processed by moving the XY stage 17 in the XY directions with respect to the XYZ axes shown in FIG. Thus, the method of processing a plurality of processing points simultaneously is called multi-beam processing, and the method of processing only a single point is called single beam processing.

  In a conventional multi-beam laser beam machine, the laser beam is spectrally branched by a polarization beam splitter, so that the energy of the laser beam emitted from the laser oscillator is halved when the workpiece is irradiated. Therefore, it is not suitable for processing that requires high energy, such as when processing copper stays.

  Further, in order to cope with high energy processing, when the laser beam emitted from the laser oscillator is set to high output, optical parts that guide the laser beam to the workpiece, such as an fθ lens and a galvanometer mirror, etc. The influence of the temperature characteristics may affect the processing accuracy, and in order to reduce the influence of the processing accuracy due to heat, it is necessary to use means such as temperature adjustment of the optical component, and the apparatus becomes expensive.

  Furthermore, since the laser beam emitted from the laser oscillator always passes through the polarization beam splitter and splits into a split beam, when processing with a single beam, one of the split laser beams is not used, so the efficiency of use of the laser oscillator is low. Become.

  The present invention has been made to solve the above-described problems, and its object is to easily perform high-speed multi-beam processing and high-energy processing of a single beam in a short time with a single multi-beam laser processing machine. The processing machine and the method that can be switched with each other are provided, and the usage of the processing machine is expanded.

  In the present invention, the polarization state of the laser beam emitted from the laser oscillator is set appropriately, and the polarization state of the laser beam is split by the polarization beam splitter before the spectrum is split by the polarization beam splitter. And a means for switching to a polarization state in which the light is not split by the spectroscopic polarizing beam splitter, and the means is controlled.

  According to the present invention, by providing a means for switching the polarization state of the laser beam emitted from the laser oscillator before the light beam is split by the polarization beam splitter, a single multi-beam laser processing machine can perform processing with a single beam. Since processing with a beam can be easily switched in a short time, even when a multi-beam laser processing machine is used with a single beam, the laser beam emitted from the laser oscillator can be used effectively.

  In addition, high-energy machining with a single beam is possible without increasing the output of the laser oscillator. Only parts that require high-energy machining are machined with a single beam, and parts that can be machined with low energy are machined with multiple beams. The processing speed can be improved as compared with the beam laser processing machine.

Embodiment 1 FIG.
FIG. 1 is a block diagram showing a multi-beam laser processing machine according to Embodiment 1 of the present invention. The configuration is basically the same as that of the conventional multi-beam laser processing machine shown in FIG. 7, but some bend mirrors 12 and masks 4 are omitted. Of course, in the optical path design, the arrangement and quantity of bend mirrors and other optical system arrangements are appropriately determined each time. A scanner that scans the split laser beams 8 and 9 in two axes will be described by taking a galvano scanner as an example. The same applies to all the following embodiments. About the same structure as FIG. 7, the same number is attached | subjected and description is abbreviate | omitted. Reference numeral 6 denotes a multi-beam unit in which optical systems from the first polarizing beam splitter 7 to the second galvano scanner 14 are put together. Reference numeral 20 denotes a quarter-wave plate inserted on the optical path of the laser beam between the laser oscillator 1 and the first polarizing beam splitter 7, and 21 denotes the quarter-wave plate 20 on the optical path of the laser beam 2. A drive device 22 for changing the position of the quarter-wave plate 20 so that it can be inserted into or removed from the optical path, and 22 is a control device for controlling the drive device 21. Reference numeral 5 denotes a laser beam transmitted through the quarter-wave plate 20. The quarter-wave plate 20, the driving device 21, and the control device 22 function as means for switching the polarization state of the laser beam incident on the first polarizing beam splitter 7.

  Next, the operation will be described. The laser beam 2 emitted from the laser oscillator 1 is linearly polarized light whose polarization direction is adjusted to be the same direction as the P wave. Here, the polarization direction is the same as that of the P wave in the state where the polarization direction is the same as that of the P wave (laser beam 8 in FIG. 1) transmitted through the first polarization beam splitter 7 and perpendicular to the incident surface. This means that the light beam is adjusted so as to be incident on the first polarization beam splitter 7. For example, when the optical system from the laser oscillator 1 to the first polarizing beam splitter 7 is as shown in FIG. 7, it enters the first polarizing beam splitter 7 with the same polarization direction as the P wave (polarization direction 8a). In other words, the polarization direction immediately after output from the laser oscillator 1 may be polarized in the X direction on the coordinate axis of FIG. The quarter-wave plate 20 is appropriately arranged so that the polarization state of the laser beam 2 can be converted from linearly polarized light to circularly polarized light when inserted into the optical path of the laser beam 2.

  Here, a case will be described in which a command is sent to the control device 22 so as to perform machining with multi-beams. The control device 22 sends a signal to the driving device 21 so that the quarter-wave plate 20 is inserted into the optical path of the laser beam 2, and the driving device 21 inserts the quarter-wave plate 20 into the optical path of the laser beam 2. To work. When the quarter-wave plate 20 is inserted on the optical path of the laser beam 2 and reaches the position A in FIG. 1, the polarization state of the laser beam 5 transmitted through the quarter-wave plate 20 is circularly polarized. The circularly polarized laser beam 5 enters the multi-beam unit 6. Since the laser beam 5 incident on the first polarization beam splitter 7 in the multi-beam unit 6 is circularly polarized, the polarization directions of the P wave and the S wave are evenly included. Are uniformly split into a laser beam 8 which is a P wave and a laser beam 9 which is an S wave. As in the conventional multi-beam laser processing machine, one of the split laser beams is guided to the second polarization beam splitter through the bend mirror 12, and the other is biaxially guided by the first galvano scanner 11. After scanning, the light is guided to the second polarizing beam splitter 10. The two laser beams are guided to substantially the same optical path by the second polarizing beam splitter 10, scanned in the biaxial direction by the second galvano scanner 14, emitted from the multi-beam unit 6, and then the fθ lens. 16 irradiates two different points on the workpiece 13 to perform multi-beam processing.

  Next, a case where a command is sent to the control device 22 to perform processing with a single beam will be described. The control device 22 sends a signal to the driving device 21 so as to remove the quarter wavelength plate 20 from the optical path of the laser beam 2, and the driving device 21 extracts the quarter wavelength plate 20 from the optical path of the laser beam 2. Operates to leave. When the quarter-wave plate 20 is removed from the optical path of the laser beam 2 and reaches the position B in FIG. 1, the laser beam 2 enters the multi-beam unit 6 while maintaining the polarization direction. Here, since the laser beam 2 is linearly polarized light adjusted in the same polarization direction as the P wave, all of the first polarization beam splitter 7 in the multi-beam unit 6 can be transmitted. Therefore, in this case, there is no laser beam 9 (laser beam indicated by a dotted line in FIG. 1), and only the laser beam 8 is present. The laser beam 8 transmitted through the first polarizing beam splitter 7 is reflected by the second polarizing beam splitter 10 via the bend mirror 12 and scanned in the biaxial direction by the second galvano scanner 14, and is a multi-beam unit. 6, irradiated through a fθ lens 16 to a desired location of the workpiece 13, and single beam processing is performed.

  As described above, the ¼ wavelength plate 20, the drive device 21, and the control device 22, which are means for switching the polarization state of the laser beam 2 incident on the first polarization beam splitter 7, are provided, and emitted from the laser oscillator 1. By appropriately setting the polarization direction of the laser beam 2 to be the same polarization direction as the P wave, it is possible to easily switch between multi-beam processing and single beam processing. Therefore, when multi-beam processing is not required, it is easy to switch to single-beam processing, so there is no need to output one of the split laser beams that is not used when performing single-beam processing with a multi-beam laser processing machine. The utilization efficiency of the laser oscillator is improved.

  In processing that requires high energy, such as when processing copper foil, even if the laser beam energy output from the laser oscillator is the same as that during multi-beam processing, switching to single beam processing Since it is not branched by the beam splitter, the energy of the laser beam can be increased twice. Therefore, high energy processing can be realized without increasing the laser output even with a multi-beam laser processing machine.

  Furthermore, since there is no need to increase the laser output, there is almost no need to consider the influence of the temperature characteristics of optical components such as the fθ lens and the second galvanometer mirror, and the influence on the processing accuracy is also high during high energy processing. almost none. Therefore, there is no need for means such as additional temperature adjustment for suppressing heat generation of the optical component during high energy processing, and cost increase can be prevented.

  Further, by processing only a portion requiring high energy with a single beam and processing a portion that can be processed with low energy by a multi-beam, the processing speed can be improved as compared with a single beam laser processing machine.

  In the above embodiment, the laser beam 2 is polarized so as to be in the same direction as the P wave, but may be polarized so as to be in the same direction as the S wave. Here, the same direction as the S wave means that the first polarization beam is reflected in the state of the same polarization direction as the S wave (laser beam 9 in FIG. 1) which reflects the first polarization beam splitter 7 and whose polarization direction is perpendicular to the incident surface. It means that it is adjusted so that it can enter the splitter 7. For example, when the optical system from the laser oscillator 1 to the first polarizing beam splitter 7 is as shown in FIG. 7, it enters the first polarizing beam splitter 7 with the same polarization direction as the S wave (polarization direction 9a). In other words, the polarization direction immediately after output from the laser oscillator 1 may be polarized in the Z direction on the coordinate axis of FIG.

  In this case, when the quarter-wave plate 20 is inserted, the laser beam 5 becomes circularly polarized light and is split by the first polarizing beam splitter 7, so that multi-beam processing is possible as described above. When the quarter-wave plate 20 is removed, the laser beam 2 is incident on the first polarization beam splitter 7 with the same polarization direction as that of the S wave, so that the entire laser beam is reflected and the laser beam 8 exists. Instead, only the laser beam 9 (laser beam indicated by a dotted line in FIG. 1) is present. In the case of only the laser beam 9, for example, the first galvano scanner 11 is fixed and the second galvano scanner 14 scans the laser beam 9 in the biaxial direction, thereby enabling single beam processing. Of course, the laser beam 9 may be scanned only by the first galvano scanner 11 or may be scanned by using both the first and second galvano scanners. Even with this configuration, single beam processing can be easily performed with a multi-beam laser processing machine, and the same effects as those of the above-described embodiment can be obtained.

Embodiment 2. FIG.
Since this embodiment has almost the same configuration as that of Embodiment 1, it will be described with reference to FIG. Reference numeral 28 denotes a polarization rotator, which is replaced with the quarter-wave plate 20 of the first embodiment. The polarization rotator 28 is appropriately arranged so as to rotate the polarization direction of the laser beam 2 by 45 degrees. As the polarization rotator, for example, a Faraday rotator or a half-wave plate is known.

  Next, the operation will be described. The laser beam 2 emitted from the laser oscillator 1 is linearly polarized light whose polarization direction is adjusted to be the same direction as the P wave. Here, the meaning of the same direction as the P wave is as described above. The polarization rotator 28 is appropriately arranged so as to rotate the polarization direction of the laser beam 2 by 45 degrees when inserted in the optical path of the laser beam 2.

  Here, a case will be described in which a command is sent to the control device 22 so as to perform machining with multi-beams. The control device 22 sends a signal to the drive device 21 to insert the polarization rotator 28 into the optical path of the laser beam 2, and the drive device 21 operates to insert the polarization rotator 28 into the optical path of the laser beam 2. . When the polarization rotator 28 is inserted in the optical path of the laser beam 2 and reaches the position A in FIG. 1, the polarization direction of the laser beam 5 transmitted through the polarization rotator 28 is linearly polarized light rotated by 45 degrees. When the light enters the unit 6, it is linearly polarized light inclined by 45 degrees with respect to the P wave. Since the laser beam 5 incident on the first polarization beam splitter 7 in the multi-beam unit 6 has a polarization direction inclined by 45 degrees with respect to the P wave, the polarization directions of the P wave and the S wave are uniformly included. Then, the first polarized beam splitter 7 splits the light equally into a laser beam 8 that is a P wave and a laser beam 9 that is an S wave. Thereby, multi-beam processing is performed in the same manner as in the conventional multi-beam processing machine or Embodiment 1.

  Next, a case where a command is sent to the control device 22 to perform processing with a single beam will be described. The control device 22 sends a signal to the driving device 21 so as to extract the polarization rotator 28 from the optical path of the laser beam 2, and the driving device 21 operates so as to extract the polarization rotator 28 from the optical path of the laser beam 2. . When the polarization rotator 28 is removed from the optical path of the laser beam 2 and reaches the position B in FIG. 1, the laser beam 2 enters the multi-beam unit 6 while maintaining the polarization direction. Here, since the laser beam 2 is linearly polarized light whose polarization direction is adjusted to the same polarization direction as the P wave, all of the first polarization beam splitter 7 in the multi-beam unit 6 can be transmitted. Thereby, the single beam processing is performed as in the first embodiment.

  As described above, the polarization rotator 28, the drive device 21, and the control device 22 are provided as means for switching the polarization state of the laser beam incident on the first polarization beam splitter, and the laser beam emitted from the laser oscillator 1 is provided. By appropriately setting the polarization direction of 2 so as to be the same polarization direction as the P wave, it is possible to easily switch between multi-beam processing and single-beam processing as in the first embodiment. Therefore, the same effect as in the first embodiment can be obtained.

  In the above embodiment, the laser beam 2 is polarized so as to be in the same direction as the P wave, but may be polarized so as to be in the same direction as the S wave. In this case, when the polarization rotator 28 is inserted, the laser beam 5 becomes linearly polarized light whose polarization direction is rotated by 45 degrees with respect to the S wave, and is split by the first polarization beam splitter 7, so that multi-beam processing is possible. It becomes. When the polarization rotator 28 is removed, the laser beam 2 is incident on the first polarization beam splitter 7 in the same polarization direction as the S wave, so that the entire laser beam 2 is reflected and the laser beam 8 exists. Since only the laser beam 9 (laser beam indicated by a dotted line in FIG. 1) exists, single beam processing is possible.

In the second embodiment, the laser beam 2 is polarized in the same direction as the P wave. However, the laser beam 2 may be linearly polarized light rotated by 45 degrees with respect to the polarization directions of the P wave and the S wave. In the above embodiment, the multi-beam machining can be performed when the polarization rotator 28 is inserted, and the single beam machining can be performed when the polarization rotator 28 is removed. become. When the polarization rotator 28 is inserted, the polarization direction of the laser beam 2 is rotated by 45 degrees, so that the polarization direction is equal to either the P wave or the S wave. Since it depends on the arrangement of the rotating polarizer 20, it may be determined as appropriate. If the polarization direction is the same as that of the P-wave or S-wave, all the laser beams are transmitted or reflected without being split by the first polarization beam splitter 7, so that single beam processing can be performed. When the polarization rotator 28 is removed, the laser beam 2 is incident on the first polarization beam splitter 7 in the polarization direction rotated 45 degrees with respect to the P wave and the S wave. .

Embodiment 3 FIG.
FIG. 2 is a block diagram showing a multi-beam laser beam machine according to Embodiment 3 of the present invention. In the present embodiment, a quarter wavelength plate 23 is added to the optical path of the laser beam 2 between the laser oscillator 1 and the quarter wavelength plate 20 in the same configuration as the first embodiment. . The quarter wavelength plate 23 is for converting the polarization state of the laser beam 2 from linearly polarized light to circularly polarized light.

  Next, the operation will be described. The laser beam 2 emitted from the laser oscillator 1 is linearly polarized light, and the polarization direction does not have to be specified. Next, the laser beam 2 is transmitted through the quarter-wave plate 23. The quarter-wave plate 23 is appropriately disposed so that the polarization state of the laser beam 2 can be converted from linearly polarized light to circularly polarized light. The state is converted to circularly polarized light. The quarter-wave plate 20 functions to convert the polarization state of the laser beam 2 from circularly polarized light to linearly polarized light when inserted into the optical path of the laser beam 2, and the polarization direction at this time is P wave or S wave. It is appropriately arranged so as to have the same polarization direction as the wave.

  Here, a case will be described in which a command is sent to the control device 22 so as to perform machining with multi-beams. The control device 22 sends a signal to the driving device 21 so as to remove the quarter wavelength plate 20 from the optical path of the laser beam 2, and the driving device 21 extracts the quarter wavelength plate 20 from the optical path of the laser beam 2. Operates to leave. When the ¼ wavelength plate 20 is removed from the optical path of the laser beam 2 and reaches the position B in FIG. 2, the circularly polarized laser beam 2 transmitted through the ¼ wavelength plate 23 is directly applied to the multi-beam unit 6. Incident. Since the laser beam 2 incident on the first polarizing beam splitter 7 in the multi-beam unit 6 is circularly polarized, it includes the polarization directions of the P wave and the S wave equally, and the first polarizing beam splitter 7 Are uniformly split into a laser beam 8 which is a P wave and a laser beam 9 which is an S wave. Thereby, multi-beam processing can be performed.

  Next, a case where a command is sent to the control device 22 to perform processing with a single beam will be described. The control device 22 sends a signal to the driving device 21 so that the quarter-wave plate 20 is inserted into the optical path of the laser beam 2, and the driving device 21 inserts the quarter-wave plate 20 into the optical path of the laser beam 2. To work. When the quarter wavelength plate 20 is inserted in the optical path of the laser beam 2 and reaches the position A in FIG. 1, the circularly polarized laser beam 2 transmitted through the quarter wavelength plate 23 is either P wave or S wave. It is converted into a linearly polarized laser beam 5 having the same polarization direction and is incident on the multi-beam unit 6. Here, since the laser beam 2 is linearly polarized light whose polarization direction is adjusted to the same polarization direction as the P wave or S wave, all of the first polarization beam splitter 7 in the multi-beam unit 6 is transmitted or reflected. Thereby, single beam processing is performed.

  As described above, the ¼ wavelength plate 20, the drive device 21, and the control device 22, which are means for switching the polarization state of the laser beam incident on the first polarization beam splitter, are provided and emitted from the laser oscillator 1. By making the laser beam 2 circularly polarized by the quarter wavelength plate 23 before entering the means for switching the polarization state, the multi-beam processing and the single beam processing can be easily switched as in the first embodiment. be able to. Therefore, the same effect as in the first embodiment can be obtained. In the first and second embodiments, the polarization direction of the laser beam 2 emitted from the laser oscillator 1 is the same as that of the P wave or S wave, or is rotated by 45 degrees with respect to the P wave and S wave. However, in this embodiment, it is not necessary to consider the polarization direction of the laser beam 2 by arranging the quarter wavelength plate 23 appropriately, and the degree of freedom regarding the arrangement of the optical system is high. There is an advantage such as.

Embodiment 4 FIG.
FIG. 3 is a block diagram showing a multi-beam laser processing machine according to Embodiment 4 of the present invention. Basically, the configuration is the same as that of the multi-beam laser processing machine of Embodiment 1 shown in FIG. 1, but the means for switching the polarization state of the laser beam incident on the first polarization beam splitter is different. Reference numeral 25 denotes an electro-optical element (hereinafter referred to as an EO element) arranged in the optical path of the laser beam 2, 26 denotes a power source for applying a voltage to an electrode (not shown) installed in the EO element 25, and 27 denotes This is a power supply control device that controls the power supply 26. The voltage value of the power supply 26 is set so that the EO element 25 transmits the laser beam 2 as it is when no voltage is applied, and functions as a quarter-wave plate when a voltage is applied. In the present embodiment, the EO element 25, the power supply 26, and the power supply control device 27 function as means for switching the polarization state of the laser beam 2 incident on the first polarization beam splitter 7.

  Next, the operation will be described. The laser beam 2 emitted from the laser oscillator 1 is linearly polarized light whose polarization direction is adjusted to be the same as the P wave or S wave. The EO element 25 is appropriately arranged so that the polarization state of the laser beam 2 can be converted from linearly polarized light to circularly polarized light when a set voltage is applied by the power supply 26 and operates as a quarter wavelength plate.

  Here, a case will be described in which a command is sent to the power supply control device 27 so as to perform processing using multi-beams. The power supply control device 27 sends a signal to the power supply 26 so as to apply the set voltage to the EO element 25, and the power supply 26 applies the set voltage to the EO element 25. Since a voltage that acts as a quarter-wave plate is applied to the EO element 25, the polarization state of the laser beam 5 transmitted through the EO element 25 is circularly polarized. The circularly polarized laser beam 5 enters the multi-beam unit 6. Since the laser beam 5 incident on the first polarization beam splitter 7 in the multi-beam unit 6 is circularly polarized, the polarization directions of the P wave and the S wave are evenly included. Are uniformly split into a laser beam 8 which is a P wave and a laser beam 9 which is an S wave. Thereby, multi-beam processing is performed.

  Next, a case where a command is sent to the power supply control device 26 to perform processing with a single beam will be described. The power supply control device 27 sends a signal to the power supply 26 so as to stop the application of the set voltage to the EO element 25, and the power supply 26 stops the application of the set voltage to the EO element 25. Since no voltage is applied to the EO element 25, the polarization state of the laser beam 5 transmitted through the EO element 25 remains unchanged, and remains linearly polarized so as to have the same polarization direction as the P wave or S wave. The laser beam 5 enters the multi-beam unit 6 while maintaining the polarization direction. Here, since the polarization direction of the laser beam 5 is linearly polarized light having the same polarization direction as the P wave or S wave, all of the first polarization beam splitter 7 in the multi-beam unit 6 is transmitted or reflected. Thereby, single beam processing is performed.

  As described above, the laser emitted from the laser oscillator 1 is provided with the EO element 25, the power supply 26, and the power supply control device 27, which are means for switching the polarization state of the laser beam 5 incident on the first polarization beam splitter 7. By appropriately setting the polarization direction of the beam 2 so as to be the same polarization direction as the P wave or S wave, it is possible to easily switch between multi-beam processing and single beam processing as in the first embodiment. . Therefore, the same effect as in the first embodiment can be obtained. In the first embodiment, the second embodiment, and the third embodiment, the driving device 21 is used as means for switching the polarization state of the laser beam 5 incident on the first polarization beam splitter 7. However, in this embodiment, since the driving device is not used and the switching is performed only by the voltage value applied to the EO element 25, the switching can be performed in a very short time compared to the other embodiments, and maintenance can be performed. There is an advantage that it is excellent in performance and a space for removing the element is not required.

Embodiment 5 FIG.
FIG. 4 is a block diagram showing a multi-beam laser beam machine according to Embodiment 5 of the present invention. In the present embodiment, a quarter wavelength plate 23 is added to the same configuration as that of the fourth embodiment on the optical path of the laser beam 2. The quarter wavelength plate 23 is for converting the polarization state of the laser beam 2 from linearly polarized light to circularly polarized light.

  Next, the operation will be described. The laser beam 2 emitted from the laser oscillator 1 is linearly polarized light, and the polarization direction does not have to be specified. Next, the laser beam 2 is transmitted through the quarter-wave plate 23. By arranging the quarter-wave plate 23 appropriately so that the polarization state of the laser beam 2 can be converted from linearly polarized light to circularly polarized light, the polarization state Is converted to circularly polarized light. The EO element 25 functions to convert the polarization state of the laser beam 2 from circularly polarized light to linearly polarized light when a set voltage is applied by the power supply 26 and operates as a quarter wave plate. The polarization direction at this time is P It is appropriately arranged so as to have the same polarization direction as the wave or S wave.

  Here, a case will be described in which a command is sent to the power supply control device 27 so as to perform processing using multi-beams. The power supply control device 27 sends a signal to the power supply 26 so as to stop the application of the set voltage to the EO element 25, and the power supply 26 stops the application of the set voltage to the EO element 25. The circularly polarized laser beam 2 transmitted through the quarter-wave plate 23 is incident on the EO element 25, but no voltage is applied to the EO element 25, so the polarization state of the laser beam 5 transmitted through the EO element 25 Is unchanged from the laser beam 2 and the polarization state remains circularly polarized. The circularly polarized laser beam 5 enters the multi-beam unit 6. Since the laser beam 5 incident on the first polarization beam splitter 7 in the multi-beam unit 6 is circularly polarized, the polarization directions of the P wave and the S wave are evenly included. Are uniformly split into a laser beam 8 which is a P wave and a laser beam 9 which is an S wave. Thereby, multi-beam processing is performed.

  Next, a case where a command is sent to the power supply control device 27 to perform processing with a single beam will be described. The power supply control device 27 sends a signal to the power supply 26 so as to apply the set voltage to the EO element 25, and the power supply 26 applies the set voltage to the EO element 25. The circularly polarized laser beam 2 that has been transmitted through the quarter-wave plate 23 is incident on the EO element 25. Since a voltage that acts as a quarter-wave plate is applied to the EO element 25, the EO element 25 The laser beam 5 that has passed through is converted into linearly polarized light having the same polarization direction as the P wave or S wave, and enters the multi-beam unit 6. Here, since the laser beam 2 is linearly polarized light whose polarization direction is adjusted to the same polarization direction as the P wave or S wave, all of the laser beam 2 is transmitted or reflected by the first polarization beam splitter 7 in the multi-beam unit 6. Thereby, single beam processing is performed.

  As described above, the EO element 25, the power source 26, and the power source control device 27, which are means for switching the polarization state of the laser beam 2 incident on the first polarization beam splitter, are provided, and the laser emitted from the laser oscillator 1 is provided. By making the beam 2 circularly polarized by the quarter wavelength plate 23 before entering the means for switching the polarization state, the multi-beam processing and the single beam processing can be easily switched as in the fourth embodiment. it can. Therefore, the same effect as in the fourth embodiment can be obtained. In the fourth embodiment, it is necessary to adjust the polarization direction of the laser beam 2 emitted from the laser oscillator 1 to be the same as the P wave or S wave. In this embodiment, the quarter wavelength plate is used. By appropriately arranging 23, there is no need to consider the polarization direction of the laser beam 2, and there is an advantage that the degree of freedom regarding the arrangement of the optical system is increased.

Embodiment 6 FIG.
In the first to fifth embodiments, the multi-beam unit 6 has been described as having the same configuration as the conventional multi-beam laser processing machine shown in FIG. 7, but for example, on the optical path of the laser beam 8 as shown in FIG. In the multi-beam unit 6 in which the bend mirror between the first polarization beam splitter 7 and the second polarization beam splitter 10 is replaced with the second galvano scanner 14 and the second galvano scanner is replaced with the bend mirror 12. It is obvious that the multi-beam processing and the single beam processing can be switched as in the first to fifth embodiments.

  In the case of multi-beam processing, the laser beam 8 is scanned in the biaxial direction by the second galvano scanner 14, and the laser beam 9 is scanned in the biaxial direction by the first galvano scanner 11. Is irradiated to two different points on the workpiece 13. In the case of single beam processing, since only the laser beam 8 or 9 is present, by scanning in the biaxial direction with a galvano scanner on the optical path of the existing laser beam, A single laser beam can be applied to a desired point on the workpiece.

  In addition, each of the divided laser beams as shown in FIG. 6 is irradiated to different points of the workpiece 13 by separate fθ lenses 16 without being mixed by the second polarization beam splitter 10. Alternatively, in a so-called single beam two-head laser processing machine that irradiates different workpieces 13 as shown in FIG. 6, the polarization state of the laser beam incident on the first polarization beam splitter 7 is changed to the first polarization. By providing a means for switching to a polarization state in which the beam is split by the beam splitter 7 or not split, two-head processing (simultaneously irradiating a laser beam from each fθ lens) and high-energy processing are possible. 1 head processing (laser beam irradiation from only one fθ lens) can be easily switched in a short time. To become.

  The present invention provides a laser processing machine capable of easily and quickly switching between multi-beam processing capable of improving processing speed by irradiating a plurality of points with a laser beam and single beam processing capable of high energy processing. For example, it is suitable for processing a multilayer substrate having a copper foil portion that requires high energy processing and a resin portion that can be processed with low energy.

It is a figure which shows Embodiment 1 and Embodiment 2 of this invention. It is a figure which shows Embodiment 3 of this invention. It is a figure which shows Embodiment 4 of this invention. It is a figure which shows Embodiment 5 of this invention. It is a figure which shows Embodiment 6 of this invention. It is a figure which shows another form of Embodiment 6 of this invention. It is a figure which shows the conventional multi-beam laser processing machine.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Laser oscillator, 2 Laser beam radiate | emitted from laser oscillator 1, 4 Mask, 5 1/4 wavelength plate 20, Laser beam which permeate | transmitted polarization rotator 28, or electro-optic element 25, 6 Multi-beam unit, 7 1st polarization | polarized-light A beam splitter, 8 a laser beam transmitted through the first polarizing beam splitter 7, 9 a laser beam reflected from the first polarizing beam splitter 7, 11 a first galvano scanner, 12 a bend mirror, 10 a second polarizing beam splitter, 14 Second Galvano Scanner, 16 fθ Lens, 13 Workpiece, 17 XY Stage, 15 Galvano Scan Area, 20, 23 1/4 Wave Plate, 21 Drive Device, 22 Control Device, 25 Electro Optical Element, 26 Power Supply 27 Power supply controller, 28 polarization rotator

Claims (12)

A laser oscillator;
A polarization beam splitter that splits the laser beam emitted from the laser oscillator into a plurality of laser beams, and a scanner that scans the split laser beam;
An fθ lens that irradiates a workpiece with the dispersed laser beam scanned by the scanner;
Means for switching the polarization state of the laser beam incident on the polarization beam splitter,
The means for switching the polarization state is:
A laser beam machine for switching between a polarization state in which the laser beam is split by the polarization beam splitter and a polarization state in which the laser beam is transmitted or reflected by the polarization beam splitter. The laser beam emitted from the laser oscillator is
A polarization state transmitted or reflected by the polarization beam splitter;
The means for switching the polarization state is:
When the laser beam is dispersed by the polarization beam splitter, the polarization state of the laser beam is changed to a polarization state that is dispersed by the polarization beam splitter, and when the laser beam is not dispersed by the polarization beam splitter, the laser 2. The laser beam machine according to claim 1, wherein the laser beam machine is switched so that the polarization state of the beam is maintained and the polarization state is transmitted or reflected by the polarization beam splitter. The polarization state of the laser beam emitted from the laser oscillator is
Linearly polarized light having the same polarization direction as the P wave transmitted by the polarizing beam splitter;
The means for switching the polarization state is:
A quarter wave plate that converts linearly polarized light into circularly polarized light;
A drive device that operates to insert the ¼ wavelength plate into or out of the optical path of the laser beam so as to convert the polarization state of the laser beam emitted from the laser oscillator into circularly polarized light; ,
A control device for controlling the operation of the drive device;
The control device includes:
When the laser beam is dispersed, the drive unit is controlled to insert the quarter-wave plate into the optical path of the laser beam. When the laser beam is not dispersed, the drive unit 3. The laser beam machine according to claim 2, wherein the quarter-wave plate is controlled to be removed from the optical path of the laser beam. The polarization state of the laser beam emitted from the laser oscillator is
Linearly polarized light having the same polarization direction as the P wave transmitted by the polarizing beam splitter;
The means for switching the polarization state is:
A polarization rotator that rotates the polarization direction by 45 degrees;
A drive device that operates to insert or remove the polarization rotator on the optical path of the laser beam so as to rotate the polarization direction of the laser beam emitted from the laser oscillator by 45 degrees;
A control device for controlling the operation of the drive device;
The control device includes:
When the laser beam is dispersed, the drive device is controlled to insert the polarization rotator into the optical path of the laser beam. When the laser beam is not dispersed, the drive device performs the polarization. 3. The laser beam machine according to claim 2, wherein the rotor is controlled so as to be removed from the optical path of the laser beam. The polarization state of the laser beam emitted from the laser oscillator is
Linearly polarized light having the same polarization direction as the P wave transmitted by the polarizing beam splitter;
The means for switching the polarization state is:
An electro-optic element disposed on the optical path of the laser beam so as to convert the polarization of the laser beam into circularly polarized light by applying a predetermined voltage;
A power source for applying a predetermined voltage to the electro-optic element;
A power supply control device for controlling the operation of the power supply,
The power supply control device
When the laser beam is dispersed, the power supply is controlled so as to apply a predetermined voltage to the electro-optical element, and when the laser beam is not dispersed, the application of the voltage to the electro-optical element is stopped. The laser processing machine according to claim 2, wherein the power supply is controlled. The polarization state of the laser beam emitted from the laser oscillator is
6. The laser beam machine according to claim 3, wherein the laser beam machine is linearly polarized light having the same polarization direction as the S wave reflected by the polarization beam splitter. The laser beam emitted from the laser oscillator is
A polarization state split by the polarization beam splitter;
The means for switching the polarization state is:
When the laser beam is split by the polarization beam splitter, the polarization state of the laser beam is maintained and the polarization state is split by the polarization beam splitter, and the laser beam is not split by the polarization beam splitter. The laser beam machine according to claim 1, wherein the laser beam is switched so that the polarization state of the laser beam is changed to a polarization state that is transmitted or reflected by the polarization beam splitter. The polarization state of the laser beam emitted from the laser oscillator is
Linearly polarized light having a polarization direction rotated by 45 degrees with respect to the P wave transmitted by the polarizing beam splitter and the S wave reflected.
The means for switching the polarization state is:
A polarization rotator that rotates the polarization direction by 45 degrees;
A drive device that operates to insert or remove the polarization rotator on the optical path of the laser beam so as to rotate the polarization direction of the laser beam emitted from the laser oscillator by 45 degrees;
A control device for sending a signal for instructing the operation to the driving device;
The control device includes:
When the laser beam is dispersed, the drive device is controlled to remove the polarization rotator from the optical path of the laser beam, and when the laser beam is not dispersed, the drive device performs the polarization. 8. The laser beam machine according to claim 7, wherein the rotor is controlled to be inserted into an optical path of the laser beam. The polarization state of the laser beam emitted from the laser oscillator is circularly polarized light,
The means for switching the polarization state is:
A second quarter wave plate for converting circularly polarized light into linearly polarized light;
The laser beam so as to convert the polarization state of the laser beam emitted from the laser oscillator and converted into circularly polarized light by the first quarter wavelength plate into linearly polarized light. A drive device that operates to be inserted into or removed from the optical path;
A control device for sending a signal for instructing the operation to the driving device;
The control device includes:
When the laser beam is dispersed, the drive unit is controlled to remove the quarter-wave plate from the optical path of the laser beam. When the laser beam is not dispersed, the drive unit is used. 8. The laser beam machine according to claim 7, wherein the quarter wave plate is controlled to be inserted into an optical path of the laser beam. The polarization state of the laser beam emitted from the laser oscillator is circularly polarized light,
The means for switching the polarization state is:
An electro-optic element arranged to convert the polarization of the laser beam into linearly polarized light by applying a predetermined voltage on the optical path of the laser beam;
A power source for applying a predetermined voltage to the electro-optic element;
A power supply control device for controlling the operation of the power supply,
The power supply control device
When the laser beam is dispersed, the power supply is controlled to stop applying a predetermined voltage to the electro-optical element. When the laser beam is not dispersed, a predetermined voltage is applied to the electro-optical element. 8. The laser beam machine according to claim 7, wherein the power source is controlled to be applied. Means for setting the polarization state of the laser beam emitted from the laser oscillator to circular polarization,
A quarter-wave plate arranged on the optical path of the laser beam between the laser oscillator and the means for switching the polarization state so as to convert the polarization state of the laser beam from linearly polarized light to circularly polarized light; The laser beam machine according to claim 9 or 10, wherein: The laser beam emitted from the laser oscillator is
Spectroscopy into multiple laser beams with a polarizing beam splitter,
Scan each of the dispersed laser beams with a scanner,
In a laser processing method of processing each laser beam scanned by the scanner by irradiating a plurality of positions on a workpiece with an fθ lens,
The polarization state of the laser beam emitted from the oscillator,
Before entering the polarizing beam splitter,
By switching between a polarization state that is split by the polarization splitter and a polarization state that is transmitted or reflected,
A laser processing method characterized by switching between a process of irradiating a plurality of positions of a workpiece with a laser beam and a process of irradiating one point of the workpiece with a laser beam.

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