JP5804881B2 - Semiconductor laser module for direct writing exposure equipment - Google Patents

Description

  The present invention relates to a light source optical system of a direct drawing exposure apparatus.

  In order to expose a pattern on a substrate such as a printed circuit board, a TFT substrate of a liquid crystal display, a color filter substrate, or a plasma display, conventionally, a mask serving as a pattern original is manufactured, and this mask is exposed to the above substrate by a mask exposure device. Was.

  However, as the dimensions of the substrates become larger and larger in recent years, the time required for designing and manufacturing these substrates is becoming shorter and shorter. For this reason, a direct drawing exposure apparatus that does not require a mask, generates a two-dimensional pattern using a two-dimensional spatial modulator such as liquid crystal or DMD (Digital Mirror Device), and exposes it on a substrate with a projection lens is practical. It became.

  As described in Patent Document 1, the conventional light source optical system of such a direct drawing exposure apparatus is configured by arranging a plurality of semiconductor lasers and aspherical lenses in an array, and then adjusting the aspherical lenses by a fine adjustment mechanism. Optical performance was obtained by fine adjustment in the direction. FIG. 14 shows the fine adjustment mechanism.

  Conventionally, when adjusting the optical axis, since the semiconductor laser 11 is completely fixed to the LD stand 51, the aspherical lens 21 is moved and adjusted in the xy direction orthogonal to the optical axis. If the XY-axis adjustment fixing screw 124 is loosened for adjustment, the aspherical lens 21 moves in the z-direction parallel to the optical axis, and the distance between the semiconductor laser 11 and the aspherical lens 21 changes. It became necessary to adjust. Therefore, the adjustment in the xy direction and the z direction has to be repeated several times, and the adjustment work takes time.

  As shown in FIGS. 15 and 16, the conventional light source optical system has a structure in which a plurality of semiconductor lasers 11 are arranged in an array and an aspheric lens 21 and an adjusting mechanism are combined. Since the arrangement pitch of the array is several millimeters, a very delicate adjustment technique on the order of μ is necessary, and one operator continuously performs the work from assembly to adjustment of the light source optical system. There was a problem with work efficiency. Furthermore, since the light source optical system having such a configuration has a complicated structure, the cooling efficiency is poor, and there is a problem that the output and life of the semiconductor laser 11 cannot be sufficiently exhibited.

  Patent Document 2 discloses a light source optical system of a drawing apparatus in which a light emitting element can be easily replaced.

  The light source optical system of Patent Document 2 includes a semiconductor laser, a collimator lens, and an alignment sleeve that are respectively disposed in a lens barrel. The semiconductor laser is completely fixed in the lens barrel, and the collimator lens is disposed in the lens barrel. Is fixed to the distal end of the cylindrical body disposed on the outer peripheral portion of the cylindrical body and the inner surface of the barrel is provided with a threaded portion that is screwed together, and by rotating the cylindrical body with respect to the barrel, The collimator lens is moved in the optical axis direction to adjust in the optical axis direction. The cylindrical body is fixed to the lens barrel by using a fixed cylinder that is screwed with a screw portion provided on the outer peripheral portion of the cylindrical body.

  A plurality of screws are erected on the outer peripheral portion of the lens barrel so as to penetrate the side wall of the lens barrel. By rotating the screws, the screws press the tube and the collimator lens is orthogonal to the optical axis. The direction perpendicular to the optical axis is adjusted by elastically deforming in the direction.

  However, the collimator lens is also distorted due to the elastic deformation of the cylinder due to the pressing of the screw tightening. This causes changes in the optical characteristics of the collimator lens (photoelastic effect), and makes axis adjustment difficult. Further, since the pressurization state continues, there is a problem that deterioration (cracking, etc.) of the collimator lens is accelerated.

JP 2005-316349 A (paragraph 0057 to paragraph 0061)

JP-A-10-339836 (paragraphs 0018 to 0024, paragraphs 0031 to 0033)

  Accordingly, it is an object to form a light source optical system of a direct drawing exposure apparatus that is easy to adjust and has excellent maintainability.

  In order to solve the above-described problems, in the present invention, the light source optical system has a module structure in which an adjustment mechanism in the xy direction orthogonal to the optical axis and an adjustment mechanism in the z direction parallel to the optical axis are separated, and the module is adjusted by itself. The adjusted modules are arranged in an array.

  As a result, the assembly / adjustment efficiency of the light source optical system is improved, and the cooling efficiency of the semiconductor laser is also improved. Therefore, the man-hour can be reduced with a stable light source.

1 is an overall configuration diagram of a semiconductor laser module according to the present invention. It is a front view of the semiconductor laser array unit which concerns on this invention. It is a side view of the semiconductor laser array unit which concerns on this invention. It is a block diagram of LD adjustment part. It is an exploded view of LD adjustment part. It is an exploded view (when it has a screw part) of an LD adjustment part. It is a block diagram of a lens adjustment part. It is an exploded view of a lens adjustment part. It is an exploded view (when it has a screw part) of a lens adjustment part. It is a block diagram of a lens holder fixing ring. It is a figure which shows an adjustment jig. It is a figure explaining the adjustment method. It is a figure which shows LD base stand. It is a block diagram of the conventional light source optical system. It is a front view of the conventional semiconductor laser array unit. It is a side view of the conventional semiconductor laser array unit.

  Hereinafter, the present invention will be described in detail based on illustrated embodiments.

  The light source optical system of the present invention is a semiconductor laser array unit in which the adjusted semiconductor laser modules 1 shown in FIG. 1 are arranged in an array as shown in FIGS.

  A method for assembling the semiconductor laser module 1 will be described. The semiconductor laser module 1 includes an LD adjustment unit 10 that adjusts the xy direction by moving the semiconductor laser 11 in a direction orthogonal to the optical axis (xy direction), and an aspheric lens 21 in a direction parallel to the optical axis (z direction). ) To adjust the z direction.

  First, the LD adjustment unit 10 is assembled. The LD adjustment unit 10 includes a semiconductor laser 11, an LD fixing holder 12, and an LD fixing cap 13.

  As shown in FIGS. 4 and 5, the semiconductor laser 11 is sandwiched between the LD fixing holder 12 and the LD fixing cap 13 and fixed in the z direction, but the two through-holes in the adjustment space portion 18 of the LD fixing cap 13. The LD pedestal 14 is pushed by the adjusting pin 42 shown in FIG.

  The inner diameter of the cylindrical portion 15 of the LD fixing holder 12 is formed larger than the outer shape of the LD for adjusting the position of the semiconductor laser 11. Further, the inner diameter of the adjustment space portion 18 of the LD fixing cap 13 is formed larger than the outer shape of the LD base for adjusting the position of the semiconductor laser 11. In this embodiment, the semiconductor laser 11 can move 1.5 mm from the center line.

  In this embodiment, as shown in FIG. 6, screw grooves are provided on the outer periphery of the cylindrical portion 15 of the LD fixing holder 12 and on the inner side of the cap portion 17 of the LD fixing cap 13. Fixed.

  Next, the lens adjustment unit 20 is assembled. The lens adjustment unit 20 includes an aspheric lens 21, an aspheric lens fixing sleeve 22, and an aspheric lens fixing holder 23.

  As shown in FIGS. 7 and 8, the aspherical lens fixing sleeve 22 is press-fitted, and the aspherical lens 21 is sandwiched by the taper portion 25 of the aspherical lens fixing sleeve 22 and fixed in the z direction. Since the aspherical lens 21 is symmetric with respect to the rotation direction and is rounded at a position in contact with the tapered portion 25, the angle of the tapered portion 25 is adjusted to the shape of the aspherical lens 21. 21 is fixed to the center of the aspherical lens fixing sleeve 22.

  The aspherical lens fixing sleeve 22 holding the aspherical lens 21 is inserted into the cylindrical tube portion 26 of the aspherical lens holder 23, and the fitting portion 27 fixes the aspherical lens fixing sleeve 22 in the z direction with the center line aligned.

  Then, the LD adjustment unit 10 and the lens adjustment unit 20 are combined. As shown in FIG. 1, an aspheric lens holder 23 holding an aspheric lens 21 and an aspheric lens fixing sleeve 22 is inserted and fixed in an LD fixing holder 12 holding a semiconductor laser 11 and an LD fixing cap 13.

  In this embodiment, as shown in FIGS. 6 and 9, screw grooves are provided on the inner side of the opening 16 of the LD fixing holder 12 and the outer periphery of the cylindrical tube portion 26 of the aspheric lens holder 23. Thus, the LD adjusting unit 10 and the lens adjusting unit 20 are fixed in the z direction, and the assembly of the semiconductor laser module 1 is completed.

  Further, in this embodiment, as shown in FIG. 10, a lens holder fixing ring 30 having a thread groove is provided inside the ring portion 31 and screwed together with the thread groove on the outer periphery of the cylindrical tube portion 26 of the aspheric lens holder 23. Thus, the LD adjustment unit 10 and the lens adjustment unit 20 are fixed.

  A method for adjusting the semiconductor laser module 1 will be described with reference to FIGS. 11 and 12. The assembled semiconductor laser module 1 is fixed to an adjustment jig 40 as shown in FIG. The adjustment jig 40 includes an XY axis stage 41, a plurality of adjustment pins 42, and micrometer heads 43 in the x and y directions.

  First, adjustment in the z direction is performed, and then adjustment in the xy direction is performed. The adjustment is completed if it can be confirmed that the laser beam is a parallel light beam at the target of the adjustment jig and the center of the optical axis is at the center of the semiconductor laser module 1.

  A method for adjusting the z direction will be described. In a state of being fixed to the adjustment jig 40, the aspherical lens fixing holder 23 holding the aspherical lens 21 is turned by hand counterclockwise from the state where it is fully inserted into the LD fixing holder 12 to form a spot shape. Observe. In this embodiment, since the spot shape changes from the divergent state to a rice grain size and converges, and the state where the rice grain size becomes divergent can be confirmed, the position where the rice grain size becomes the first is a parallel light beam. , Fix in this position. In this way, adjustment in the z direction is performed, and the lens holder fixing ring 30 is used for fixing.

  An adjustment method in the xy direction will be described. An adjustment pin 42 is inserted into each of the two through holes 19 opened in the adjustment space portion 18 of the LD fixing cap 13, and the micrometer provided on the XY axis stage 41 with the two adjustment pins 42 pressing the LD base 14. By moving the two adjustment pins 42 in the xy direction while turning the knob of the head 43, the semiconductor laser 11 is moved in the xy direction for fine adjustment. After the adjustment, the LD fixing cap 13 is tightened and fixed.

  After the adjustment, the adjustment pin 42 is removed, the semiconductor laser module 1 is removed from the adjustment jig 40, and the adjustment of the semiconductor laser module 1 is completed.

  The laser beam emitted from the assembled and adjusted semiconductor laser module 1 is an elliptical beam, but is adjusted so as to be a circular spot in the subsequent optical system.

  A structure in which a plurality of semiconductor laser modules 1 that have been assembled and adjusted are aligned in a direction in which the longer one of the elliptical beams becomes vertical while checking with the target of the adjusting jig, and the holes are regularly opened as shown in FIG. The semiconductor laser array unit is completed by press-fitting into the LD base stand 50. For fine adjustment of the optical axis, an optical axis correction system such as a wedge-shaped wedge glass disclosed in Patent Document 1 is used.

  As described above, the LD adjustment unit moves the semiconductor laser 11 in the xy direction to adjust the xy direction perpendicular to the optical axis, and the lens adjustment unit moves the aspheric lens 21 in the z direction to the optical axis. Since the adjustment in the parallel z direction is performed and the adjustment mechanism in the xy direction and the z direction is separated, the adjustment need not be repeated.

  In the prior art, the adjustment is performed after the semiconductor laser and the adjustment mechanism are arranged in an array. In the present invention, the adjustment mechanism is modularized, and after the semiconductor laser module 1 is adjusted in the xyz direction, the LD is adjusted. Since it can be arranged on the base stand 50 and a large adjustment space can be secured, the adjustment becomes easy.

  In addition, adjustment work, which occupies a large amount of man-hours, can be done by multiple people, but it has become possible to cope with short delivery times.

  Furthermore, the adjustment when the semiconductor laser module 1 is removed for maintenance can be easily performed.

DESCRIPTION OF SYMBOLS 1 Semiconductor laser module 2 Semiconductor laser array unit 10 LD adjustment part 11 Semiconductor laser (LD)
12 LD fixing holder 13 LD fixing cap 20 Lens adjustment part 21 Aspherical lens (collimator lens)
22 Aspherical lens fixing sleeve 23 Aspherical lens holder 30 Lens holder fixing ring 40 Adjustment jig 50 LD base stand

Claims (3)

An LD fixing holder having a semiconductor laser, and a cylindrical portion and an opening for inserting the semiconductor laser, the inner diameter of the cylindrical portion being formed larger than the outer diameter of the LD for position adjustment of the semiconductor laser; A cap portion and an adjustment space portion for inserting the cylindrical portion of the LD fixing holder are formed, and the inner diameter of the adjustment space portion is formed larger than the outer diameter of the LD base for adjusting the position of the semiconductor laser. An LD fixing cap provided with a plurality of through holes into which LD adjustment pins for moving are inserted;
An aspheric lens that collimates laser light emitted from the semiconductor laser, an aspheric lens fixing sleeve having a tapered portion and a cylindrical sleeve portion for sandwiching the aspheric lens with a center line aligned, and the LD fixing A cylindrical tube portion to be inserted into the opening of the holder is provided, and the aspheric lens fixing sleeve is press-fitted inside the cylindrical tube portion, and the center line of the aspheric lens is aligned and held by the tapered portion. A semiconductor laser module comprising an aspherical lens holder having a fitting portion for the purpose.
2. The semiconductor laser module according to claim 1, further comprising a lens holder fixing ring having a ring portion for inserting the aspheric lens holder. A semiconductor laser array unit comprising the plurality of semiconductor laser modules according to claim 1.

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