Laser processing head and laser processing apparatus

Abstract

The invention relates to a laser processing head and a laser processing apparatus. The laser processing head includes: a housing; a first mirror that reflects the laser light; a plate-shaped second mirror that reflects a portion of the laser light reflected by the first mirror and transmits another portion of the laser light reflected by the first mirror; a condensing unit that condenses a portion of the laser light on an object; a light detection unit that detects another part of the laser light; and a measurement unit that outputs measurement light and detects the measurement light reflected by the object via the light collecting unit. The second mirror transmits the measurement light traveling from the measurement unit to the light collecting unit and the measurement light traveling from the light collecting unit to the measurement unit.

Description

Technical Field

[0001] This disclosure relates to laser processing heads and laser processing apparatus. Background Technology

[0002] As a laser processing head used in laser processing apparatus, one known laser processing head includes: a housing; an adjustment section disposed within the housing for adjusting the laser used in processing; and a focusing section mounted on the housing for focusing the laser adjusted by the adjustment section onto an object; a measuring section disposed within the housing outputs measuring light, and the measuring light reflected by the object is detected by the focusing section (for example, see Japanese Patent Application Laid-Open No. 2021-171802). In such a laser processing head, sometimes the focusing section is mounted on the housing via a drive section, and the drive section moves the focusing section in a direction parallel to the optical axis of the focusing section based on a signal output from the measuring section. Summary of the Invention

[0003] In laser processing heads like those described above, for example, when forming a modified region at a predetermined depth inside an object, it is important to accurately detect the measuring light in the measuring unit. Furthermore, for example, when forming a modified region inside an object in a desired state, it is important to accurately detect a portion of the laser light irradiating the object.

[0004] The purpose of this disclosure is to provide a laser processing head capable of detecting a portion of a laser and measuring light with high precision, and a laser processing apparatus having such a laser processing head.

[0005] One aspect of this disclosure is a laser processing head, [1] "a laser processing head comprising: a housing; a first mirror disposed within the housing for reflecting a laser for processing; a plate-shaped second mirror disposed within the housing for reflecting a portion of the laser reflected by the first mirror and allowing another portion of the laser reflected by the first mirror to pass through; a focusing unit mounted on the housing for focusing the portion of the laser reflected by the second mirror onto an object; a light detection unit disposed within the housing for detecting the portion of the laser that has passed through the second mirror; and a measuring unit disposed within the housing for outputting measuring light, detecting the measuring light reflected by the object via the focusing unit, wherein the second mirror allows the measuring light traveling from the measuring unit to the focusing unit and the measuring light traveling from the focusing unit to the measuring unit to pass through.

[0006] In the aforementioned laser processing head, a portion of the laser light reflected by the first mirror passes through the second mirror and enters the light detection unit. This avoids, for example, ghosting reflections (reflections caused by surfaces other than the mirror surface) that might occur in the second mirror when a portion of the laser light is reflected and enters the light detection unit, thus enabling high-precision detection of a portion of the laser light in the light detection unit. Furthermore, measurement light from the object side passes through the focusing section and enters the measurement unit through the second mirror. This avoids, for example, ghosting reflections that might occur in the second mirror when the measurement light is reflected and enters the measurement unit, thus enabling high-precision detection of the measurement light in the measurement unit. Therefore, according to the aforementioned laser processing head, both a portion of the laser light and the measurement light can be detected with high precision.

[0007] One aspect of the laser processing head disclosed herein can also be, [2] "the laser processing head as described in [1] above, further comprising: an observation section disposed within the housing, outputting observation light, detecting the observation light reflected by the object via the focusing section, a first mirror allowing the observation light traveling from the observation section to the focusing section and from the focusing section to the observation section to pass through, and a second mirror reflecting the observation light traveling from the first mirror to the focusing section and from the focusing section to the first mirror." According to this laser processing head, the observation light from the object side passing through the focusing section passes through the first mirror and enters the observation section. Thus, for example, it is possible to avoid ghosting reflections that may occur in the first mirror when the observation light is reflected by the first mirror and enters the observation section.

[0008] One aspect of the laser processing head disclosed herein may also be, [3] "the laser processing head as described in [2] above, further comprising: a third mirror disposed within the housing, reflecting the observation light traveling from the observation section to the first mirror; and a fourth mirror disposed within the housing, reflecting the observation light traveling from the first mirror to the observation section." According to this laser processing head, it is possible to suppress the enlargement of the housing and to extend the optical path length of the observation light. Extending the optical path length of the observation light is beneficial to improving the magnification of the observation section and enabling high-precision observation. When the optical path length of the observation light is determined by the focal distance of the focusing section and the magnification of the observation section, and it is difficult to change the focal distance of the focusing section for the laser used in processing in order to obtain the desired focusing state, the magnification of the observation section can be improved by increasing the optical path length of the observation light.

[0009] One aspect of the laser processing head disclosed herein may also be, [4] "a laser processing head as described in [2] or [3] above, wherein the observation section detects a portion of the measurement light reflected by the object and passing through the focusing section, which is reflected by the second mirror and passes through the first mirror, and a portion of the laser light reflected by the object and passing through the focusing section, which is reflected by the second mirror and passes through the first mirror." According to this laser processing head, the state of the measurement light and the state of the laser light (e.g., the spot position of the measurement light and the laser light used for processing on the surface of the object) can be monitored.

[0010] One aspect of the laser processing head disclosed herein may also be, [5] "a laser processing head as described in any one of [1] to [4] above, wherein the optical axis of the measuring light traveling from the measuring section to the focusing section is offset to one side of the optical axis of the focusing section in the focusing section, and the optical axis of the measuring light traveling from the focusing section to the measuring section is offset to the other side of the optical axis of the focusing section in the focusing section." According to this laser processing head, the height information of a specified surface of an object can be obtained using the eccentric triangulation method.

[0011] One aspect of the laser processing head disclosed herein may also be, [6] "a laser processing head as described in any one of [1] to [5] above, wherein the mirror unit including the first mirror and the second mirror, the light detection unit including the light detection section, and the measurement unit including the measurement section are respectively detachable from the housing." According to this laser processing head, maintenance of the first and second mirrors, maintenance of the light detection section, and maintenance of the measurement section can be easily performed. That is, maintenance of the target unit does not affect other units, and the target unit can be detached independently.

[0012] One aspect of the laser processing head disclosed herein may also be, [7] "a laser processing head as described in any one of [1] to [6] above, further comprising: a driving unit mounted on the housing, which moves the focusing unit in a direction parallel to the optical axis of the focusing unit; and a circuit unit disposed within the housing, which controls the driving unit based on a signal output from the measuring unit." According to this laser processing head, the laser focusing spot can be positioned at a predetermined position inside the object, with a predetermined surface of the object as a reference.

[0013] One aspect of the laser processing head disclosed herein may also be, [8] "a laser processing head as described in any one of [1] to [7] above, further comprising: a spatial light modulator disposed within the housing for modulating and reflecting the laser traveling toward the first mirror; and an imaging optical system disposed within the housing for transmitting the laser traveling from the spatial light modulator toward the first mirror, the imaging optical system constituting a two-sided telecentric optical system in which the reflecting surface of the spatial light modulator is in an imaging relationship with the entrance pupil surface of the focusing portion and the reflecting surface of the spatial light modulator is in an imaging relationship with the light-receiving surface of the light detection portion." According to this laser processing head, the modulated image of the laser on the reflecting surface of the spatial light modulator is transferred to the entrance pupil surface of the focusing portion, thus enabling high-precision processing of the object using the modulated laser. In addition, the modulated image of the laser on the reflecting surface of the spatial light modulator is transferred to the light-receiving surface of the light detection portion, thus enabling monitoring of the modulation state of the laser.

[0014] One aspect of this disclosure of the laser processing head can also be, [9] "the laser processing head as described above [8], wherein it further comprises: an attenuator disposed within the housing for adjusting the output of the laser traveling toward the spatial light modulator; and a beam expander disposed within the housing for expanding the beam diameter of the laser traveling toward the spatial light modulator." According to this laser processing head, the laser can be modulated while the output is adjusted and the beam diameter is expanded.

[0015] One aspect of this disclosure is a laser processing apparatus,

[10] "a laser processing apparatus comprising: a laser processing head as described in any one of [1] to [9] above; a mounting portion on which the housing of the laser processing head is mounted; a light source that outputs the laser incident on the laser processing head; and a support portion that supports the object."

[0016] According to the laser processing device described above, a portion of the laser beam and the light can be detected and measured with high precision in the laser processing head, thus enabling the processing of objects with high precision. Attached Figure Description

[0017] Figure 1 This is a three-dimensional diagram of an example laser processing device.

[0018] Figure 2 yes Figure 1 A front view of a portion of the laser processing apparatus shown.

[0019] Figure 3 yes Figure 1 The front view of the laser processing head is shown.

[0020] Figure 4 yes Figure 1The image shows a side view of the laser processing head.

[0021] Figure 5 yes Figure 4 The diagram shows the structure of the laser processing head.

[0022] Figure 6 yes Figure 5 A structural diagram of a portion of the measuring section is shown.

[0023] Figure 7 yes Figure 5 The diagram shows a portion of the structure of the laser processing head. Detailed Implementation

[0024] Hereinafter, an example of this disclosure will be described in detail with reference to the accompanying drawings. Furthermore, identical or equivalent parts are labeled with the same symbols in the various drawings, and repeated descriptions are omitted.

[0025] [Structure of laser processing equipment]

[0026] like Figure 1 As shown, the laser processing apparatus 1 includes multiple moving mechanisms 5 and 6, a support 7, a pair of laser processing heads 10A and 10B, a light source unit 8, and a control unit 9. Hereinafter, the three mutually perpendicular directions will be referred to as the X direction, Y direction, and Z direction. In the laser processing apparatus 1, the Z direction is the vertical direction, and the X and Y directions are the horizontal directions.

[0027] The moving mechanism 5 includes a fixed part 51, a moving part 53, and a mounting part 55. The fixed part 51 is mounted on the device frame 1a. The moving part 53 is mounted on a track provided on the fixed part 51 and is capable of moving along the Y direction. The mounting part 55 is mounted on a track provided on the moving part 53 and is capable of moving along the X direction.

[0028] The moving mechanism 6 has a fixed part 61, a pair of moving parts 63 and 64, and a pair of mounting parts 65 and 66. The fixed part 61 is mounted on the device frame 1a. The pair of moving parts 63 and 64 are respectively mounted on the track provided on the fixed part 61 and can move independently along the Y direction. The mounting part 65 is mounted on the track provided on the moving part 63 and can move along the Z direction. The mounting part 66 is mounted on the track provided on the moving part 64 and can move along the Z direction.

[0029] The support 7 is mounted on a rotating shaft provided in the mounting portion 55 of the moving mechanism 5, and is capable of rotating about an axis parallel to the Z direction. The support 7 supports the object W. The object W is, for example, a wafer.

[0030] like Figure 1 and Figure 2As shown, laser processing head 10A is mounted on mounting portion 65 of the moving mechanism 6. When laser processing head 10A is facing support portion 7 in the Z direction, it irradiates the object W supported on support portion 7 with laser L for processing. Laser processing head 10B is mounted on mounting portion 66 of the moving mechanism 6. When laser processing head 10B is facing support portion 7 in the Z direction, it irradiates the object W supported on support portion 7 with laser L.

[0031] like Figure 1 As shown, the light source unit 8 has a pair of light sources 81 and 82. The pair of light sources 81 and 82 are mounted on the device frame 1a. The pair of light sources 81 and 82 respectively output laser light L. The laser light L emitted from the emission portion 81a of the light source 81 is guided to the laser processing head 10A through the optical fiber 2. The laser light L emitted from the emission portion 82a of the light source 82 is guided to the laser processing head 10B through the other optical fiber 2.

[0032] The control unit 9 controls various parts of the laser processing apparatus 1 (multiple moving mechanisms 5, 6, a pair of laser processing heads 10A, 10B, and the light source unit 8, etc.). The control unit 9 is configured as a computer device including a processor, memory, storage, and communication equipment. In the control unit 9, software (programs) loaded into the memory, etc., is executed by the processor, and the reading and writing of data in the memory and storage, as well as communication via the communication equipment, are controlled by the processor. Thus, the control unit 9 performs various functions. The control unit 9 has a display 91. The display 91 displays various information. The display 91 may also be configured as a touch panel that accepts input from operator instructions.

[0033] The laser processing apparatus 1 configured as described above can be used for various purposes, such as cutting wafers, slicing wafers to thin them, and trimming wafers by removing their outer peripheries. Here, an example of processing performed by the laser processing apparatus 1 will be described. This example is an example of cutting an object W, which is a wafer, into multiple chips, and forming modified regions inside the object W along multiple lines set in a lattice pattern (i.e., an example of the first half of the cutting process).

[0034] First, with the object W supported by the support part 7, the moving mechanism 5 moves the support part 7 along the X and Y directions respectively, with the laser processing head 10A facing the support part 7, and the moving mechanism 6 moves the laser processing head 10A along the Y direction. Next, with multiple lines extending in one direction in the object W along the X direction, the moving mechanism 5 rotates the support part 7 about an axis parallel to the Z direction as its center line.

[0035] Next, the moving mechanism 6 moves the support 7 along the Y direction so that the focusing spot of the laser L emitted from the laser processing head 10A (hereinafter referred to as "laser L of laser processing head 10A") is located on a line extending in one direction. Next, the moving mechanism 6 moves the laser processing head 10A along the Z direction so that the focusing spot of the laser L of laser processing head 10A is located inside the object W.

[0036] Next, the light source 81 emits laser L, causing the laser processing head 10A to irradiate the object W with laser L. Simultaneously, the moving mechanism 5 moves the support 7 along the X direction, causing the focusing point of the laser L from the laser processing head 10A to move relative to each other along a line extending in one direction. In this way, the laser processing apparatus 1 forms modified regions within the object W along multiple lines extending in one direction.

[0037] Next, the moving mechanism 5 rotates the support 7 around an axis parallel to the Z direction, with multiple lines extending along the X direction in the object W in another direction orthogonal to one direction.

[0038] Next, the moving mechanism 6 moves the support 7 along the Y direction so that the focusing spot of the laser L of the laser processing head 10A is located on a line extending in another direction. Next, the moving mechanism 6 moves the laser processing head 10A along the Z direction so that the focusing spot of the laser L of the laser processing head 10A is located inside the object W.

[0039] Next, the light source 81 emits laser L, causing the laser processing head 10A to irradiate the object W with laser L. Simultaneously, the moving mechanism 5 moves the laser processing head 10A along the X direction, causing the focused spot of the laser L from the laser processing head 10A to move relative to a line extending in another direction. In this way, the laser processing apparatus 1 forms a modified region within the object W along multiple lines extending in a direction orthogonal to one direction.

[0040] In one example of the above processing, the light source 81 emits a laser L that is transmissible to the object W via pulse oscillation. When such laser L is focused inside the object W, it is specifically absorbed at the point corresponding to the focused spot, forming a modified region inside the object W. The modified region is a region whose density, refractive index, mechanical strength, and other physical properties differ from the surrounding unmodified region. Examples of modified regions include melt-processed regions, cracked regions, insulation failure regions, and regions with refractive index changes.

[0041] When a laser L emitted via pulse oscillation irradiates an object W, and the focused spot of laser L moves relative to the object W along a line set on the object W, multiple modified spots are formed and arranged in a row along the line. A single modified spot is formed by irradiation with one pulse of laser L. A modified region is a collection of multiple modified spots arranged in a row. Adjacent modified spots may be connected or separated depending on the relative movement speed of the focused spot of laser L relative to the object W and the repetition frequency of laser L.

[0042] In one example of the above processing, laser processing head 10A is used to form the modified region, but laser processing head 10B can also be used. When using laser processing head 10B, the modified region can be formed inside the object W through the same operation as when using laser processing head 10A. In the laser processing apparatus 1, laser processing heads 10A and 10B are arranged in the Y direction; therefore, by a single relative movement of laser processing heads 10A and 10B along the X direction, the formation of individual modified regions along multiple lines extending in the X direction can be implemented.

[0043] [Structure of laser processing head]

[0044] like Figure 2 , Figure 3 and Figure 4 As shown, the laser processing head 10A includes a housing 11, an incident section 12, an optical element section 13, and a focusing section 14.

[0045] The housing 11 has a first wall portion 21, a second wall portion 22, a third wall portion 23 and a fourth wall portion 24, and a fifth wall portion 25 and a sixth wall portion 26. The first wall portion 21 and the second wall portion 22 are opposite to each other in the X direction. The third wall portion 23 and the fourth wall portion 24 are opposite to each other in the Y direction. The fifth wall portion 25 and the sixth wall portion 26 are opposite to each other in the Z direction.

[0046] The distance between the third wall portion 23 and the fourth wall portion 24 is smaller than the distance between the first wall portion 21 and the second wall portion 22. The distance between the first wall portion 21 and the second wall portion 22 is smaller than the distance between the fifth wall portion 25 and the sixth wall portion 26. Furthermore, the distance between the first wall portion 21 and the second wall portion 22 can be equal to or greater than the distance between the fifth wall portion 25 and the sixth wall portion 26.

[0047] In the laser processing head 10A, the first wall portion 21 is located on the opposite side of the fixed portion 61 of the moving mechanism 6, and the second wall portion 22 is located on the side of the fixed portion 61. The third wall portion 23 is located on the side of the mounting portion 65 of the moving mechanism 6, and the fourth wall portion 24 is located on the opposite side of the mounting portion 65, i.e., on the side of the laser processing head 10B. The fifth wall portion 25 is located on the opposite side of the support portion 7, and the sixth wall portion 26 is located on the side of the support portion 7.

[0048] The housing 11 is configured such that, with the third wall portion 23 disposed on the mounting portion 65 side of the moving mechanism 6, the housing 11 is mounted on the mounting portion 65. The mounting portion 65 has a base plate 65a and a mounting plate 65b. The base plate 65a is mounted on a track provided on the moving portion 63. The mounting plate 65b is erected at the end of the base plate 65a on the side of the laser processing head 10B. With the third wall portion 23 in contact with the mounting plate 65b, the housing 11 is mounted on the mounting portion 65 by screwing it onto the mounting plate 65b via bolts 28 on the base 27. The base 27 is respectively provided on the first wall portion 21 and the second wall portion 22. The housing 11 can be attached to and detached from the mounting portion 65.

[0049] An incident portion 12 is disposed on the fifth wall portion 25. The incident portion 12 allows the laser L to enter the housing 11. The incident portion 12 is biased toward the first wall portion 21 in the X direction and toward the fourth wall portion 24 in the Y direction. That is, the distance between the incident portion 12 and the first wall portion 21 in the X direction is less than the distance between the incident portion 12 and the second wall portion 22 in the X direction, and the distance between the incident portion 12 and the fourth wall portion 24 in the Y direction is less than the distance between the incident portion 12 and the third wall portion 23 in the Y direction.

[0050] The exit end 2a of the optical fiber 2 is connected to the incident portion 12. The incident portion 12 includes a hole 25a formed in the fifth wall portion 25. A mounting portion 25b is provided in the fifth wall portion 25. The main body portion 2b of the exit end 2a is mounted to the mounting portion 25b by bolts or the like. In this state, the front end portion 2c of the exit end 2a passes through the hole 25a. Thus, the exit end 2a of the optical fiber 2 can be attached to and detached from the incident portion 12. A cover 25c is disposed between the fifth wall portion 25 and the main body portion 2b. The cover 25c covers the gap formed between the hole 25a and the front end portion 2c. As an example, in the exit end 2a, an isolator for suppressing backlight is disposed in the main body portion 2b, and a collimating lens for collimating the laser L is disposed in the front end portion 2c. Alternatively, the incident portion 12 may also be configured as a connector or the like to connect the exit end 2a of the optical fiber 2.

[0051] An optical element section 13 is disposed within a housing 11. The optical element section 13, for example, adjusts the laser L incident from the incident section 12. The optical element section 13 is disposed within the housing 11 on the fourth wall 24 side relative to the partition wall 29. Each structure of the optical element section 13 is mounted on the partition wall 29 on the fourth wall 24 side. The partition wall 29 is provided within the housing 11, dividing the area within the housing 11 into a region on the third wall 23 side and a region on the fourth wall 24 side. The partition wall 29 is formed as part of the housing 11. The partition wall 29 functions as an optical base supporting the various structures of the optical element section 13.

[0052] A light-concentrating part 14 is disposed on the sixth wall portion 26. The light-concentrating part 14 passes through a hole 26a formed in the sixth wall portion 26 (see reference). Figure 5 The laser beam 14 is positioned in the sixth wall portion 26. The focusing unit 14 focuses the laser beam L, adjusted by the optical element unit 13, and emits it outward from the housing 11. The focusing unit 14 is biased towards the second wall portion 22 in the X direction and towards the fourth wall portion 24 in the Y direction. That is, the distance between the focusing unit 14 and the second wall portion 22 in the X direction is less than the distance between the focusing unit 14 and the first wall portion 21 in the X direction, and the distance between the focusing unit 14 and the fourth wall portion 24 in the Y direction is less than the distance between the focusing unit 14 and the third wall portion 23 in the Y direction.

[0053] like Figure 5 As shown, the optical element section 13 includes a mirror 31, an attenuator 32, a beam expander 33, and a mirror 34. The mirror 31, attenuator 32, beam expander 33, and mirror 34 are arranged on a straight line parallel to the X-direction. The mirror 31 is opposite to the incident section 12 in the Z-direction. The mirror 31 receives the laser L (in the incident section 12) incident from the incident section 12. Figure 5 (Represented by solid lines) The laser light (reflected by mirror 31) is reflected towards the second wall portion 22. Attenuator 32 adjusts the output of the laser L reflected by mirror 31. Beam expander 33 enlarges the diameter of the laser L whose output has been adjusted by attenuator 32. Mirror 34 reflects the laser L, whose diameter has been enlarged by beam expander 33, towards the sixth wall portion 26. Mirrors 31 and 34 are, for example, plate-type mirrors or prism-type mirrors.

[0054] The optical element section 13 also includes an optical axis adjustment section 35 and a mirror 36. The optical axis adjustment section 35 is a mechanism for adjusting the optical axis of the laser L. The optical axis adjustment section 35 includes a first steering mirror 351 and a second steering mirror 352. The mirror 36 reflects the laser L, which is reflected sequentially by the first steering mirror 351 and the second steering mirror 352, toward the first wall section 21 side and the fifth wall section 25 side. The mirror 36 is, for example, a plate-type mirror or a prism-type mirror.

[0055] The first steering mirror 351 includes a mirror 351a and a retainer 351b. The mirror 351a is mounted on the retainer 351b. The retainer 351b is mounted on the partition wall 29. The retainer 351b holds the mirror 351a in a manner that allows adjustment of the orientation of the mirror 351a. The first steering mirror 351 reflects the laser L reflected by the mirror 34 toward the first wall 21 side and the fifth wall 25 side.

[0056] The second steering mirror 352 includes a mirror 352a and a retainer 352b. The mirror 352a is mounted on the retainer 352b. The retainer 352b is mounted on the partition wall 29. The retainer 352b holds the mirror 352a in a manner that allows adjustment of the orientation of the mirror 352a. The second steering mirror 352 reflects the laser L reflected by the first steering mirror 351 toward the first wall 21 side and the sixth wall 26 side.

[0057] As an example, the tool can be accessed via a covered opening (not shown) formed in the housing 11 relative to each of the retainers 351b and 352b. Thus, by observing the image obtained by the observation section 45 and operating the tool, the orientation of each of the mirrors 351a and 352a can be adjusted so that the optical axis of the laser L incident on the focusing section 14 is aligned with the optical axis of the focusing section 14.

[0058] The optical element section 13 also includes a spatial light modulator 37 and an imaging optical system 38. The spatial light modulator 37 and the imaging optical system 38 are arranged on a straight line parallel to the Z-direction. The spatial light modulator 37 modulates the laser L reflected by the mirror 36 and reflects it towards the sixth wall section 26. The spatial light modulator 37 is a reflective type spatial light modulator. For example, the spatial light modulator 37 is an LCOS (Liquid Crystal on Silicon)-SLM (Spatial Light Modulator). The imaging optical system 38 forms a telecentric optical system on both sides of the spatial light modulator 37, where the reflecting surface 37a of the spatial light modulator 37 and the entrance pupil surface 14a of the focusing section 14 are in an imaging relationship. The imaging optical system 38 is composed of multiple lenses.

[0059] The optical element section 13 also includes a first mirror 41 and a second mirror 42. The first mirror 41 and the second mirror 42 are arranged on a straight line parallel to the X direction. The first mirror 41 is opposite to the imaging optical system 38 in the Z direction. The first mirror 41 reflects the laser L that has passed through the imaging optical system 38 toward the second wall section 22. The second mirror 42 is opposite to the focusing section 14 in the Z direction. The second mirror 42 reflects a portion La of the laser L reflected by the first mirror 41 toward the sixth wall section 26, while the other portion Lb of the laser L reflected by the first mirror 41 passes through toward the second wall section 22. The focusing section 14 focuses the portion La of the laser L reflected by the second mirror 42 toward the object W.

[0060] The optical element section 13 also includes a light detection section 43. The light detection section 43 is opposite to the second mirror 42 in the X direction. The light detection section 43 detects a portion Lb of the laser L that has passed through the second mirror 42. The light detection section 43 is, for example, composed of a two-dimensional sensor such as a CMOS (Complementary Metal Oxide Semiconductor) image sensor. In addition, in the telecentric optical systems on both sides of the imaging optical system 38, the reflecting surface 37a of the spatial light modulator 37 and the light-receiving surface 43a of the light detection section 43 are in an imaging relationship. That is, the imaging optical system 38 constitutes a telecentric optical system on both sides in which the reflecting surface 37a of the spatial light modulator 37 is in an imaging relationship with the entrance pupil surface 14a of the focusing section 14, and the reflecting surface 37a of the spatial light modulator 37 and the light-receiving surface 43a of the light detection section 43 are in an imaging relationship.

[0061] The optical element section 13 also includes a measuring section 44. The measuring section 44 is positioned opposite the condenser section 14 to the second mirror 42. The measuring section 44 outputs measuring light L10 (in... Figure 5 (Indicated by a single-dotted line), the measurement light L10 reflected by the object W is detected by the focusing unit 14. At this time, the second mirror 42 allows the measurement light L10 traveling from the measuring unit 44 to the focusing unit 14 and from the focusing unit 14 to the measuring unit 44 to pass through. As an example, the measurement light L10 is a laser used to measure the height (in other words, the distance between the surface and the focusing unit 14) of the surface of the object W (e.g., the surface on the side where the laser L is incident). In this case, the measurement light L10 output from the measuring unit 44 is irradiated onto the surface of the object W via the second mirror 42 and the focusing unit 14, and the measurement light L10 reflected by the surface of the object W is detected in the measuring unit 44 via the focusing unit 14 and the second mirror 42.

[0062] like Figure 6As shown, the optical axis A1 of the measurement light L10 traveling from the light source 441 of the measurement unit 44 to the focusing unit 14 is shifted to one side from the optical axis A of the focusing unit 14. The optical axis A2 of the measurement light L10 traveling from the focusing unit 14 to the light detection unit 442 of the measurement unit 44 after being reflected by the surface Wa of the object W is shifted to the other side (opposite to one side) from the optical axis A of the focusing unit 14. The optical axis A1 of the measurement light L10 incident from the light source 441 of the measurement unit 44 to the focusing unit 14 is parallel to the optical axis A of the focusing unit 14, and the optical axis A1 of the measurement light L10 emitted from the focusing unit 14 is tilted such that the focusing point C of the measurement light L10 focused by the focusing unit 14 is located on the optical axis A of the focusing unit 14. Therefore, depending on the height of the surface Wa of the object W, the light path of the measuring light L10, which is reflected by the surface Wa and passes through the focusing section 14, changes. As a result, the incident position of the measuring light L10 changes on the light-receiving surface of the light detection section 442 of the measuring section 44, depending on the height of the surface Wa of the object W. Therefore, the height of the surface Wa of the object W can be measured based on the incident position of the measuring light L10 on the light-receiving surface of the light detection section 442.

[0063] like Figure 5 As shown, the optical element section 13 also includes an observation section 45, a third mirror 46, and a fourth mirror 47. The observation section 45 includes a light source 451 and a camera 452. The third mirror 46 is disposed on the opposite side of the second mirror 42 relative to the first mirror 41. The fourth mirror 47 is disposed on the opposite side of the first mirror 41 relative to the third mirror 46. The light source 451 is disposed on the fifth wall section 25 side relative to the third mirror 46. The camera 452 is disposed on the fifth wall section 25 side relative to the fourth mirror 47. The camera 452 is, for example, a two-dimensional sensor such as a CMOS image sensor.

[0064] The observation unit 45 outputs observation light L20 (in) Figure 5(Indicated by dashed lines), the observation light L20 reflected by the object W is detected by the focusing unit 14. In the observation unit 45, the observation light L20 is output from the light source 451 and detected by the camera 452. At this time, the third mirror 46 reflects the observation light L20 traveling from the light source 451 to the first mirror 41, allowing the observation light L20 traveling from the first mirror 41 to the fourth mirror 47 to pass through. The fourth mirror 47 reflects the observation light L20 traveling from the first mirror 41 through the third mirror 46 to the camera 452. The first mirror 41 allows the observation light L20 traveling from the light source 451 to the focusing unit 14 and from the focusing unit 14 to the camera 452 to pass through. The second mirror 42 reflects the observation light L20 traveling from the first mirror 41 to the focusing unit 14 and from the focusing unit 14 to the first mirror 41. As an example, the observation light L20 is visible light used to observe the surface of the object W (e.g., the surface on the side where the laser L is incident). In this case, the observation light L20 output from the light source 451 is irradiated onto the surface of the object W via the third mirror 46, the first mirror 41, the second mirror 42, and the focusing unit 14. The observation light L20 reflected by the surface of the object W is detected in the camera 452 via the focusing unit 14, the second mirror 42, the first mirror 41, the third mirror 46, and the fourth mirror 47. Furthermore, the wavelengths of the laser L, the measuring light L10, and the observation light L20 are all different (at least their center wavelengths are offset from each other).

[0065] As described above, in the optical element section 13, the attenuator 32 adjusts the output of the laser L traveling towards the spatial light modulator 37. The beam expander 33 expands the beam diameter of the laser L traveling from the attenuator 32 towards the spatial light modulator 37. The spatial light modulator 37 modulates and reflects the laser L traveling towards the first mirror 41. The imaging optical system 38 allows the laser L traveling from the spatial light modulator 37 towards the first mirror 41 to pass through. The optical element section 13 is configured with an "optical unit 300 including the spatial light modulator 37 and the imaging optical system 38", a "mirror unit 400 including the first mirror 41, the second mirror 42, the third mirror 46, and the fourth mirror 47", a "light detection unit 430 including a light detection unit 43", a "measurement unit 440 including a measurement unit 44", and an "observation unit 450 including an observation unit 45". The optical unit 300, the mirror unit 400, the light detection unit 430, the measurement unit 440, and the observation unit 450 are each detachable from the partition wall section 29. That is, each unit 300, 400, 430, 440, and 450 can be mounted and dismounted relative to the housing 11. As an example, each unit 300, 400, 430, 440, and 450 can be accessed via a covered opening (not shown) formed in the housing 11. Thus, maintenance can be performed on each unit.

[0066] like Figure 3 and Figure 5As shown, the laser processing head 10A also includes a drive unit 18 and a circuit unit 19. In the laser processing apparatus 1, the circuit unit 19 is electrically connected to the control unit 9, thereby functioning as part of the control unit 9. That is, in the laser processing apparatus 1, the circuit unit 19 constitutes part of the control unit 9.

[0067] The drive unit 18 is mounted on the partition wall 29 on the side of the fourth wall 24. The focusing unit 14 is mounted on the partition wall 29 via the drive unit 18. That is, the drive unit 18 is mounted on the housing 11, and the focusing unit 14 is mounted on the housing 11 via the drive unit 18. The drive unit 18 moves the focusing unit 14 in a direction parallel to the optical axis A of the focusing unit 14, for example, by the driving force of the piezoelectric element.

[0068] The circuit section 19 is disposed within the housing 11 on the side of the third wall portion 23, opposite to the partition wall portion 29. That is, the circuit section 19 is disposed within the housing 11 on the side of the third wall portion 23, opposite to the optical element portion 13. The circuit section 19 is separate from the partition wall portion 29. The circuit section 19 is, for example, composed of multiple circuit boards. The circuit section 19 processes the signal output from the measurement unit 44 and the signal input to the spatial light modulator 37. The circuit section 19 controls the drive unit 18 based on the signal output from the measurement unit 44. As an example, the circuit section 19 controls the drive unit 18 based on the signal output from the measurement unit 44 to maintain a constant distance between the surface of the object W and the focusing unit 14 (that is, to maintain a constant distance between the surface of the object W and the focusing spot C of the laser L).

[0069] Furthermore, the partition wall 29 has cutouts, holes, etc. (not shown) through which wiring for electrically connecting the various structures of the optical element section 13 to the circuit section 19 passes. In addition, the housing 11 is provided with connectors (not shown) for connecting wiring for electrically connecting the circuit section 19 and the control section 9.

[0070] The laser processing head 10B, like the laser processing head 10A, includes a housing 11, an incident section 12, an optical element section 13, a focusing section 14, a driving section 18, and a circuit section 19. However, the structures of the laser processing head 10B are as follows: Figure 2 As shown, the structures of the laser processing head 10A are arranged in a manner that is symmetrical with respect to an imaginary plane passing through the midpoint between a pair of mounting parts 65 and 66 and perpendicular to the Y direction.

[0071] For example, the housing 11 of the laser processing head 10A is mounted on the mounting portion 65 such that the fourth wall portion 24 is located on the laser processing head 10B side relative to the third wall portion 23, and the sixth wall portion 26 is located on the support portion 7 side relative to the fifth wall portion 25. Conversely, the housing 11 of the laser processing head 10B is mounted on the mounting portion 66 such that the fourth wall portion 24 is located on the laser processing head 10A side relative to the third wall portion 23, and the sixth wall portion 26 is located on the support portion 7 side relative to the fifth wall portion 25.

[0072] The housing 11 of the laser processing head 10B is configured such that the housing 11 is mounted on the mounting portion 66 with the third wall portion 23 disposed on the mounting portion 66 side. The mounting portion 66 has a base plate 66a and a mounting plate 66b. The base plate 66a is mounted on a track provided in the moving portion 63. The mounting plate 66b is erected at the end of the base plate 66a on the laser processing head 10A side. The housing 11 of the laser processing head 10B is mounted on the mounting portion 66 with the third wall portion 23 in contact with the mounting plate 66b. The housing 11 of the laser processing head 10B can be attached to and detached from the mounting portion 66.

[0073] [The structure of each mirror contained in the mirror unit]

[0074] Reference Figure 7 The mirrors 41, 42, 46, and 47 included in mirror unit 400 will be described. Figure 7 In, with Figure 5 Similarly, solid lines represent laser light L, dashed lines represent measuring light L10, and dashed lines represent observation light L20.

[0075] like Figure 7 As shown, the first mirror 41 is a plate-shaped mirror having a pair of main surfaces 41a and 41b. As an example, the first mirror 41 is a plate-shaped dichroic mirror constructed by forming a dielectric multilayer film on the surface of a light-transmitting substrate. In the first mirror 41, the main surface 41a is the side of the dielectric multilayer film located relative to the light-transmitting substrate. The main surface 41a faces the second wall portion 22 and the fifth wall portion 25 (see reference). Figure 5 In the state of ), it is tilted in a manner that is parallel to the Y direction and at an angle of 45° relative to the X and Z directions.

[0076] The second mirror 42 is a plate-shaped mirror having a pair of main surfaces 42a and 42b. As an example, the second mirror 42 is a plate-shaped dichroic mirror constructed by forming a dielectric multilayer film on the surface of a light-transmitting substrate. In the second mirror 42, the main surface 42a is the side of the dielectric multilayer film located relative to the light-transmitting substrate. The main surface 42a faces the first wall portion 21 and the sixth wall portion 26 (see reference). Figure 5 In the state of ), it is tilted in a manner that is parallel to the Y direction and at an angle of 45° relative to the X and Z directions.

[0077] The third mirror 46 is a plate-shaped mirror having a pair of main surfaces 46a and 46b. As an example, the third mirror 46 is a plate-shaped dichroic mirror constructed by forming a dielectric multilayer film on the surface of a light-transmitting substrate. In the third mirror 46, the main surface 46a is the side of the dielectric multilayer film located relative to the light-transmitting substrate. The main surface 46a faces the second wall portion 22 and the fifth wall portion 25 (see reference). Figure 5 In the state of ), it is tilted in a manner that is parallel to the Y direction and at an angle of 45° relative to the X and Z directions.

[0078] The fourth mirror 47 is a plate-shaped mirror having a pair of main surfaces 47a and 47b. As an example, the fourth mirror 47 is a plate-shaped total internal reflection mirror constructed by forming a metal film on the surface of a substrate. In the fourth mirror 47, the main surface 47a is the side of the metal film located relative to the substrate. The main surface 47a faces the second wall portion 22 and the fifth wall portion 25 (see reference). Figure 5 In the state of ), it is tilted at an angle parallel to the Y direction and at 45° relative to the X and Z directions. The fourth mirror 47 can also be a prism-type mirror.

[0079] Here, an example of the reflectance of each of the lenses 41, 42, 46, and 47 relative to the laser L with a center wavelength of 1099 nm, the measurement light L10 with a center wavelength of 850 nm, and the observation light L20 with a center wavelength of 630 nm will be described. The first lens 41 has a reflectance of 95% or more relative to the laser L, a reflectance of 5% or less relative to the measurement light L10, and a reflectance of 5% or less relative to the observation light L20. The second lens 42 has a reflectance of 95% or more relative to the laser L, a reflectance of less than 50% relative to the measurement light L10, and a reflectance of 50% or more relative to the observation light L20.

[0080] The third mirror 46 has a reflectivity of 95% or higher relative to the laser L, a reflectivity of less than 50% relative to the measurement light L10, and a reflectivity of 50% or higher relative to the observation light L20. In the second mirror 42 and the third mirror 46, a coating is applied to the dielectric multilayer film such that the reflectivity to the measurement light L10 is greater than the reflectivity to the observation light L20, thereby achieving component commonality. The fourth mirror 47 has a reflectivity of 99% or higher relative to the laser L, a reflectivity of 99% or higher relative to the measurement light L10, and a reflectivity of 99% or higher relative to the observation light L20.

[0081] As described above, a portion Lb of the laser L reflected by the first mirror 41 and transmitted through the second mirror 42, a portion of the measurement light L10 output from the measurement unit 44 and reflected by the second mirror 42, and a portion of the observation light L20 output from the light source 451 of the observation unit 45 and reflected by the third mirror 46 and transmitted through the first mirror 41 and the second mirror 42 are incident on the light detection unit 43. That is, the light detection unit 43 can detect not only a portion Lb of the laser L, but also a portion of the measurement light L10 and a portion of the observation light L20. Therefore, the outlines of the laser L, the measurement light L10, and the observation light L20 can be observed.

[0082] In addition, a portion of the observation light L20, which is reflected by the surface of the object W and passes through the focusing section 14, is reflected by the second mirror 42, passes through the first mirror 41 and the third mirror 46, and is reflected by the fourth mirror 47; a portion of the laser L, which is reflected by the surface of the object W and passes through the focusing section 14, is reflected by the second mirror 42, passes through the first mirror 41 and the third mirror 46, and is reflected by the fourth mirror 47; and a portion of the measurement light L10, which is reflected by the surface of the object W and passes through the focusing section 14, is reflected by the second mirror 42, passes through the first mirror 41 and the third mirror 46, and is reflected by the fourth mirror 47, is incident on the camera 452 of the observation section 45. That is, the observation section 45 can detect not only a portion of the observation light L20, but also a portion of the laser L and a portion of the measurement light L10. By detecting the observation light L20 performed by the observation section 45, it is possible to observe the object W, observe the markings, and obtain information about the relative position of the laser processing head 10A relative to the object W. The position information of laser L can be obtained by detecting laser L through observation unit 45. The position information of measuring light L10 can be obtained by detecting measuring light L10 through observation unit 45.

[0083] [Functions and Effects]

[0084] In the laser processing head 10A, a portion Lb of the laser L reflected by the first mirror 41 passes through the second mirror 42 and is incident on the light detection unit 43. Therefore, for example, ghosting reflections (based on reflections from surfaces other than the mirror surface) that might occur in the second mirror 42 when a portion of the laser L is reflected by the second mirror 42 and incident on the light detection unit 43 can be avoided, thus enabling high-precision detection of a portion of the laser L in the light detection unit 43. Additionally, the measurement light L10, which passes through the focusing section 14 from the object W side, passes through the second mirror 42 and is incident on the measurement unit 44. Therefore, for example, ghosting reflections that might occur in the second mirror 42 when the measurement light L10 is reflected by the second mirror 42 and incident on the measurement unit 44 can be avoided, thus enabling high-precision detection of the measurement light L10 in the measurement unit 44. Therefore, according to the laser processing head 10A, both a portion of the laser L and the measurement light L10 can be detected with high precision. The ability to avoid ghosting reflections in the second mirror 42 by using a plate-type second mirror 42 instead of an expensive cubic beam splitter is extremely useful.

[0085] In the laser processing head 10A, the first mirror 41 allows the observation light L20 traveling from the observation section 45 to the focusing section 14 and from the focusing section 14 to the observation section 45 to pass through, while the second mirror 42 reflects the observation light L20 traveling from the first mirror 41 to the focusing section 14 and from the focusing section 14 to the first mirror 41. Thus, the observation light L20, having passed through the focusing section 14 from the object W side, passes through the first mirror 41 and enters the observation section 45. Therefore, for example, it is possible to avoid ghosting reflections that might occur in the first mirror 41 if the observation light L20 is reflected by the first mirror 41 and enters the observation section 45.

[0086] In the laser processing head 10A, the observation light L20 traveling from the observation section 45 to the first mirror 41 is reflected by the third mirror 46, and the observation light L20 traveling from the first mirror 41 to the observation section 45 is reflected by the fourth mirror 47. This helps to suppress the enlargement of the housing 11 and extends the optical path length of the observation light L20. Extending the optical path length of the observation light L20 is beneficial for improving the magnification of the observation section 45, enabling high-precision observation. When the optical path length of the observation light L20 is determined by the focal distance of the focusing section 14 and the magnification of the observation section 45, and it is difficult to change the focal distance of the focusing section 14 for the processing laser L in order to obtain the desired focusing state, increasing the optical path length of the observation light L20 can improve the magnification of the observation section 45.

[0087] In the laser processing head 10A, the observation unit 45 detects "a portion of the measurement light L10 reflected by the object W and passing through the focusing unit 14, which is then reflected by the second mirror 42 and passes through the first mirror 41" and "a portion of the laser L reflected by the object W and passing through the focusing unit 14, which is then reflected by the second mirror 42 and passes through the first mirror 41". This allows for monitoring of the state of the measurement light L10 and the state of the laser L (e.g., the position of the light spot of the measurement light L10 and the laser L on the surface of the object W).

[0088] In the laser processing head 10A, the optical axis A1 of the measuring light L10 traveling from the measuring section 44 to the focusing section 14 is shifted to one side from the optical axis A of the focusing section 14, and the optical axis A2 of the measuring light L10 traveling from the focusing section 14 to the measuring section 44 is shifted to the other side from the optical axis A of the focusing section 14. Therefore, the height information of a specified surface of the object W can be obtained using the eccentric triangulation method.

[0089] In the laser processing head 10A, each unit 300, 400, 430, 440, and 450 can be mounted and dismounted relative to the housing 11. This allows for easy maintenance of the spatial light modulator 37 and the imaging optical system 38, as well as the mirrors 41, 42, 46, and 47, the photodetector 43, the measuring unit 44, and the observation unit 45. In other words, maintenance of the target unit does not affect other units, and the target unit can be mounted and dismounted independently.

[0090] In the laser processing head 10A, a drive unit 18 is used to control the movement of the focusing unit 14 in a direction parallel to the optical axis A of the focusing unit 14, based on a signal output from the measuring unit 44. This allows the focusing spot C of the laser L to be positioned at a predetermined location inside the object W, using a predetermined surface of the object W as a reference.

[0091] In the laser processing head 10A, the imaging optical system 38 is a telecentric optical system consisting of two sides where the reflecting surface 37a of the spatial light modulator 37 and the entrance pupil surface 14a of the focusing section 14 are in an imaging relationship, and the reflecting surface 37a of the spatial light modulator 37 and the light-receiving surface 43a of the light detection section 43 are in an imaging relationship. Therefore, the modulated image of the laser L at the reflecting surface 37a of the spatial light modulator 37 is transferred to the entrance pupil surface 14a of the focusing section 14, thus enabling high-precision processing of the object W using the modulated laser L. Furthermore, the modulated image of the laser L at the reflecting surface 37a of the spatial light modulator 37 is transferred to the light-receiving surface 43a of the light detection section 43, thus enabling monitoring of the modulation state of the laser L.

[0092] In the laser processing head 10A, the output of the laser L traveling toward the spatial light modulator 37 is adjusted by the attenuator 32, and the beam diameter of the laser L traveling toward the spatial light modulator 37 is enlarged by the beam expander 33. Thus, the laser L can be modulated while the output is adjusted and the beam diameter is enlarged.

[0093] The same functions and effects are achieved by the laser processing head 10B.

[0094] According to the laser processing apparatus 1, a portion of the laser L and the light L10 can be detected and measured with high precision in each laser processing head 10A, 10B, thus enabling high-precision processing of the object W.

[0095] [Variation Example]

[0096] This disclosure is not limited to the example described above. For example, attenuator 32 may also be configured in the optical path of laser L between beam expander 33 and spatial light modulator 37. Furthermore, when the measuring unit 44 obtains the height information of a predetermined surface of the object W using eccentric triangulation, the direction of the offset of the optical axes A1 and A2 of the measuring light L10 is not limited to the X direction; for example, it may be the Y direction. In this case, the position of the spot of the measuring light L10 can be monitored by the observation unit 45 to ensure that the spot of the measuring light L10 on the predetermined surface of the object W is located within the cut street. Additionally, the measuring unit 44 may also obtain the height information of the predetermined surface of the object W using methods other than eccentric triangulation (e.g., laser confocal method, white confocal method, beam splitting interference method, astigmatism method, etc.). Furthermore, the third mirror 46 and the fourth mirror 47 may not be configured in the optical path of the observation light L20 between the first mirror 41 and the observation unit 45.

[0097] The housing 11 can be mounted on the mounting portion 65 (or mounting portion 66) with at least one of the first wall portion 21, the second wall portion 22, the third wall portion 23 and the fifth wall portion 25 disposed on the mounting portion 65 (or mounting portion 66) side of the laser processing apparatus 1.

[0098] The light source unit 8 may also have a light source. In this case, the light source unit 8 only needs to be configured to emit a portion of the laser output from a light source from the emission section 81a and emit another portion of the laser from the emission section 82a.

[0099] The laser processing apparatus 1 may have one laser processing head or more than three laser processing heads. The laser processing apparatus 1 is not limited to forming a modified region inside the object W, but may also be used to perform other laser processing.

[0100] According to this disclosure, a laser processing head capable of detecting a portion of a laser and measuring light with high precision, and a laser processing apparatus having such a laser processing head, can be provided.

Claims

1. A laser processing head, wherein, have: case; The first mirror, which is disposed inside the housing, reflects the laser used for processing; A plate-shaped second mirror, disposed within the housing, reflects a portion of the laser light reflected by the first mirror and allows another portion of the laser light reflected by the first mirror to pass through; A focusing section, which is mounted on the housing, focuses the portion of the laser light reflected by the second mirror relative to the object; A light detection unit, disposed within the housing, detects a portion of the laser light that has passed through the second mirror; and A measuring unit, disposed within the housing, outputs measuring light, and the measuring light reflected by the object is detected by the focusing unit. The second mirror allows the measurement light traveling from the measuring section to the focusing section and the measurement light traveling from the focusing section to the measuring section to pass through.

2. The laser processing head according to claim 1, wherein, It also includes: an observation unit disposed within the housing, which outputs observation light, and the observation light reflected by the object is detected by the focusing unit. The first mirror allows the observation light traveling from the observation section to the focusing section and the observation light traveling from the focusing section to the observation section to pass through. The second mirror reflects the observation light traveling from the first mirror toward the condenser and the observation light traveling from the condenser toward the first mirror.

3. The laser processing head according to claim 2, wherein, It also has: A third mirror, disposed within the housing, reflects the observation light traveling from the observation section toward the first mirror; and A fourth mirror, disposed within the housing, reflects the observation light traveling from the first mirror toward the observation unit.

4. The laser processing head according to claim 2 or 3, wherein, The observation unit detects a portion of the measurement light reflected by the object and passing through the focusing unit, which is then reflected by the second mirror and passes through the first mirror, and a portion of the laser light reflected by the object and passing through the focusing unit, which is then reflected by the second mirror and passes through the first mirror.

5. The laser processing head according to any one of claims 1 to 4, wherein, The optical axis of the measuring light traveling from the measuring section to the focusing section is offset to one side of the optical axis of the focusing section. The optical axis of the measuring light traveling from the focusing section to the measuring section is offset to the other side of the optical axis of the focusing section within the focusing section.

6. The laser processing head according to any one of claims 1 to 5, wherein, The mirror unit including the first mirror and the second mirror, the light detection unit including the light detection section, and the measurement unit including the measurement section can be mounted and dismounted relative to the housing.

7. The laser processing head according to any one of claims 1 to 6, wherein, It also has: A drive unit, mounted on the housing, moves the focusing unit in a direction parallel to the optical axis of the focusing unit; and The circuit section, which is disposed within the housing, controls the drive section based on the signal output from the measuring section.

8. The laser processing head according to any one of claims 1 to 7, wherein, It also has: A spatial light modulator, disposed within the housing, modulates and reflects the laser beam traveling toward the first mirror; and An imaging optical system, disposed within the housing, allows the laser beam traveling from the spatial light modulator toward the first mirror to pass through. The imaging optical system comprises a two-sided telecentric optical system in which the reflecting surface of the spatial light modulator is in an imaging relationship with the entrance pupil surface of the focusing part, and the reflecting surface of the spatial light modulator is in an imaging relationship with the light-receiving surface of the light detection part.

9. The laser processing head according to claim 8, wherein, It also has: An attenuator, disposed within the housing, regulates the output of the laser traveling toward the spatial light modulator; and A beam expander, disposed within the housing, expands the beam diameter of the laser beam traveling toward the spatial light modulator.

10. A laser processing apparatus, wherein, have: The laser processing head according to any one of claims 1 to 9; The mounting section has the housing on which the laser processing head is mounted; A light source, the output of which is the laser incident on the laser processing head; and A support portion that supports the object.

Images