JP5525367B2 - Lens position adjustment mechanism - Google Patents

Description

  The present invention relates to a lens position adjusting mechanism for a lens used in a lens spot measuring device or the like.

  In order to inspect whether there is any scratch or distortion on the lens surface of the pickup lens, a spot measuring device using laser light, such as that described in Patent Document 1, is used. The spot measurement device used in Patent Document 1 transmits a laser beam emitted from a laser light source through a lens and enters the measurement camera, and displays an image of a lens spot image displayed on a monitor connected to the measurement camera. Is a device for observing. For this reason, in the spot measuring device, it is necessary to position the lens image by the laser light at a position where it is formed on the imaging surface of the measuring camera. In other words, the spot measurement device needs to have a position adjustment mechanism that adjusts the position and inclination of the lens.

  The above-described position adjusting mechanism needs to move at least the lens in parallel (in the three orthogonal directions) and rotationally move (around two orthogonal axes orthogonal to the optical axis). A conventional position adjustment mechanism includes an inclination stage that inclines a sample stage for holding a lens around two orthogonal axes orthogonal to the optical axis, and an XYZ stage that translates the inclination stage itself in three orthogonal axes.

  A top view and a side view of a conventional tilt stage are shown in FIGS. A conventional tilt stage 701 includes a frame 720 in which a fixed plate 721 fixed to an XYZ stage and a sample table holding plate 722 extending in the horizontal direction from the upper end of the fixed plate 721 are integrally formed, and an opening of the sample table holding plate 722. An outer ring portion 712 that is rotatably held around the tilt axis tx1 in the 722a, a sample stage 711 that is rotatably held around the tilt axis tx2 orthogonal to the tilt axis tx1 inside the outer ring portion 712, and an outer ring portion The first tilt drive mechanism 730 tilts the 712 around the tilt axis tx1 relative to the frame portion 720, and the second tilt drive mechanism 740 tilts the sample stage 711 around the tilt axis tx2 relative to the outer ring portion 712.

  The first tilt drive mechanism 730 includes a first operation grip 731 and a first arm 732 fixed to the outer ring portion 712. The first operation grip 731 has a fixed portion fixed to the frame portion 720, and a pin 731a that can advance and retreat in the horizontal direction perpendicular to the tilt axis tx1 according to the operation of the first operation grip 731. The arm 732 is biased by the coil spring 733 so as to come into contact with the pin 731a. For this reason, the outer ring part 712 can be inclined around the inclination axis tx1 by advancing and retracting the pin 731a.

  The second tilt drive mechanism 740 includes a second operation grip 741 and a second arm 742 fixed to the sample table 711. The second operation grip 741 is fixed to the fixed portion fixed to the first arm 732 via the relay frame 744 and the surface direction of the outer ring portion 712 perpendicular to the tilt axis tx2 according to the operation of the second operation grip 741. The second arm 732 is biased by a coil spring 743 so as to contact the pin 741a. For this reason, by moving the pin 741a back and forth, the sample stage 711 can be tilted around the tilt axis tx2.

JP 2004-45327 A

  As described above, the tilt stage 701 used in the conventional position adjustment mechanism can tilt the sample stage 711 about two axes by operating the first operation grip 731 and the second operation grip 741. It is what you want to do. However, since the second operation grip 741 is not fixed to the frame portion 720 and can be swung around the tilt axis tx1 integrally with the outer ring portion 712, the sample stage 711 is tilted around the tilt axis tx2. When the second operation grip 741 is operated, the second operation grip 741 and the outer ring portion 712 may swing around the tilt axis tx1. Therefore, in the conventional position adjustment mechanism, it is necessary to carefully operate the second operation grip 741 so as not to swing in order to tilt the lens in an appropriate direction, and the lens position adjustment operation becomes complicated. In addition, the time required to tilt the lens to a desired position is long.

  The present invention has been made to solve the above problems. That is, an object of the present invention is to provide a lens position adjusting mechanism capable of adjusting the position of a lens with a simple and short-time operation.

  In order to achieve the above object, the lens position adjusting mechanism of the present invention is orthogonal to the first axis with respect to the frame, the outer ring portion rotatable about the first axis with respect to the frame, and the outer ring portion. A sample stage that is rotatable about the second axis and that holds the lens, a first arm that is connected to the outer ring part and rotates the outer ring part about the first axis, and a sample stage, A second arm that is rotatably connected around a third axis parallel to the first axis, and rotates the sample stage around the second axis; a fixed portion fixed to the frame; and a forward and backward movement with respect to the fixed portion First and second driving means including a movable part; first biasing means for biasing the first arm so that the first arm comes into contact with the movable part of the first driving means; Second urging means for urging the second arm so that the second arm comes into contact with the movable portion of the second driving means; And a third biasing means for urging the second arm so that the tip portion of the second arm abuts the frame a third axis around.

  In the configuration described above, the sample stage can be rotated around the second axis via the second arm by the second driving means. The fixing portion of the second driving means is fixed to the frame, the second arm is rotatable around the third axis, and the second arm is attached to the frame by the third biasing means. It is energized. For this reason, even if the sample stage and the outer ring portion are rotated around the first axis by the first driving means, the contact state between the movable portion of the second driving means and the second arm is maintained. Therefore, according to the configuration of the present invention, the sample stage is not rotated around the first axis when the second driving means is operated, and the lens position can be adjusted in a simple and short time operation. A simple lens position adjustment mechanism is realized.

  In addition, a configuration in which a friction reducing means for reducing a friction force acting between the frame and the tip of the second arm is provided between the frame and the tip of the second arm is provided. preferable. The friction reducing means is, for example, a roller provided at the tip of the second arm and rolling along the frame.

  With such a configuration, even if the distal end portion of the second arm is pressed toward the frame, the frictional force acting between the distal end portion of the second arm and the frame becomes small. Can be easily and accurately rotated about the second axis.

  The sample stage has a plate-like portion on which the lens is held and a connection block fixed to the lower surface of the plate-like part of the sample stage, and the connection block is rotatable around the third axis. It is good also as a structure connected with an arm.

  The sample table has a guide bar fixed to the plate-like portion of the sample table and extending perpendicularly to the lower surface of the plate-like portion of the sample table, and the second arm is a plate formed with a through hole through which the guide bar is inserted The third urging means includes a coil spring that is passed between the tip of the guide bar and the plate-like portion of the second arm.

  As described above, according to the present invention, a lens position adjustment mechanism for a lens that can adjust the position of the lens with a simple and short-time operation is realized.

FIG. 1 is a block diagram of a spot measuring apparatus according to an embodiment of the present invention. FIG. 2 is a top view of the spot measuring apparatus according to the embodiment of the present invention. FIG. 3 is a front view of the spot measuring apparatus according to the embodiment of the present invention. FIG. 4 is a top view of the tilt stage according to the embodiment of the present invention. 5 is a cross-sectional view taken along the line AA in FIG. FIG. 6 is a perspective view of the tilt stage according to the embodiment of the present invention. FIG. 7 is a cross-sectional view taken along line AA of FIG. 4 in a state where the sample stage is tilted counterclockwise. FIG. 8 is a cross-sectional view taken along line AA of FIG. 4 in a state where the sample stage is tilted clockwise. FIG. 9 is a top view of a conventional tilt stage. FIG. 10 is a side view of a conventional tilt stage.

  Embodiments of the present invention will be described below. FIG. 1 is a block diagram of the spot measuring apparatus of the present embodiment. 2 and 3 are a top view and a front view of the spot measuring apparatus according to the present embodiment. As shown in FIGS. 1 to 3, the spot measurement apparatus 1 of the present embodiment includes a light source unit 200, an XYZ stage 300, an inclined stage 400, a detection unit 500, and a control unit 600.

  The function of the spot measuring device 1 will be described below. The spot measuring apparatus 1 according to the present embodiment transmits a laser beam generated by the laser diode 211 of the light source unit 200 to a transmissive lens (condenser lens or the like) OP that is an object, and transmits the laser beam through the lens OP. Light is incident on the measurement video camera 520 via the objective lens unit 510 of the detection unit 500. The objective lens unit 510 is disposed at a position where an image of the lens OP by the incident laser light forms an image near the light receiving surface of the image sensor 522 of the measurement video camera 520. The video signal of the video taken by the measurement video camera 520 is sent to the computer 611 of the control unit 600. The computer 611 processes the video acquired from the measurement video camera 520 and displays it on the monitor 612, so that the spot image of the laser beam can be observed on the monitor 612. The objective lens unit 510 is an optical system that enlarges the spot image at a magnification of about 50 to 100 times, and the shape of the spot image is displayed on the monitor 612 in detail. The user of the spot measuring apparatus 1 can determine whether or not there is a scratch, distortion, or the like on the surface of the lens OP from the shape of the spot image displayed on the monitor 612.

  As shown in FIG. 1, the laser diode 211 of the light source unit 200 irradiates laser light in a substantially horizontal direction. The laser light generated by the laser diode 211 is converted into parallel light by the collimator lens 212, then bent in the vertical direction by the reflection mirror 213, and enters the lens OP held on the tilt stage 400.

  In the present embodiment, it is necessary to accurately form an image of the laser light transmitted through the lens OP on the light receiving surface of the image sensor 522. Therefore, the optical axis of the lens OP coincides with the traveling direction of the laser light incident on the lens OP and the optical axis ax of the optical system downstream of the lens OP (the objective lens unit 510 and the lens 521 of the measurement video camera 520). As described above, the light source unit 200, the detection unit 500, and the lens OP need to be accurately positioned. The light source unit 200 and the detection unit 500 are strictly positioned with respect to the base 100 (FIG. 2) so that the direction of the laser light emitted from the light source unit 200 and the optical axis of the optical system constituting the detection unit 500 coincide. Has been fixed.

  The positioning of the lens OP is performed by operating the XYZ stage 300 and the tilt stage 400. The configurations of the XYZ stage 300 and the tilt stage 400 will be described below. As shown in FIGS. 2 and 3, the XYZ stage 300 is fixed on the base 100. Further, the XYZ stage 300 includes three grips 311, 312, and 313 extending in two orthogonal horizontal and vertical axis directions. Each of the grips 311 to 313 incorporates a precise feed screw mechanism. By rotating the grips 311 to 313, the tilt stage 400 fixed to the XYZ stage 300 is horizontally moved in the three orthogonal directions. It can be made to.

  The configuration of the tilt stage 400 will be described below. FIG. 4 is a top view of the tilt stage 400. FIG. 5 is a cross-sectional view taken along the line AA in FIG. FIG. 6 is a perspective view of the tilt stage 400 as viewed obliquely from below.

  As shown in FIGS. 4 to 6, the tilt stage 400 tilts the sample stage 411 on which the lens OP (FIG. 1) is placed around two axes. As shown in FIG. 4, the sample stage 411 is a disk in which an opening 411 o for attaching a lens OP is formed at the center, and a pair of holes drilled in the direction toward the center of the sample stage 411 on the side surface of the disk. Pin holes 411a and 411b are formed. The pin holes 411a and 411b are formed at positions facing each other across the center of the sample table 411 (that is, the diameter of the sample table 411 is located on the line connecting the pin holes 411a and 411b). .

  An outer ring portion 412 is disposed around the sample table 411. The outer ring portion 412 has four pin holes 412a, 412b, 412c, and 412d formed in this order in the clockwise direction at intervals of 90 ° toward the center (FIG. 4).

  The tilt stage 400 has a frame part 420. The frame unit 420 is formed by integrally forming a fixed plate 421 fixed to the XYZ stage 300 and a sample stage holding plate 422 extending from one end (upper end) of the fixed plate 421 in the horizontal direction. In addition, a rib plate 423 that connects both the sample table holding plate 422 and the fixed plate 421 is fixed, and the fixed plate 421 and the sample table holding plate 422 are integrated with the rib plate 423 with high rigidity. It has become. An opening 422a is formed substantially at the center of the sample table holding plate 422, and the sample table 411 and the outer ring portion 412 are accommodated in the opening 422a. On the inner peripheral surface of the opening 422a, pin holes 422b and 422c drilled outward in the horizontal direction are formed (FIG. 4). The pin hole 412b of the outer ring portion 412 and the pin hole 422b of the sample stand holding plate 422, and the pin hole 412d of the outer ring portion 412 and the pin hole 422c of the sample stand holding plate 422 are connected via the pin p1, respectively. The sample stage 411 and the outer ring portion 412 are supported so as to be rotatable around an axis (inclination axis tx1) connecting the pin holes 412b and 412d of the outer ring portion 412 to the frame portion 420.

  The pin hole 411a of the sample table 411 and the pin hole 412a of the outer ring portion 412 and the pin hole 411b of the sample table 411 and the outer ring portion 412 are connected via the pin p2, respectively. The portion 412 is supported so as to be rotatable around an axis (inclination axis tx2) connecting the pin holes 411a and 411b.

  As described above, the sample stage 411 can be tilted (rotated) about two orthogonal axes with respect to the frame portion 420 (that is, with respect to the base 100 on which the tilt stage 400 is fixed via the XYZ stage 300). Yes. In the present embodiment, the lens OP to be measured is attached to the tilt stage 400 so that the tilt axes tx1 and tx2 of the tilt stage 400 are located near the principal point position of the lens OP. . With this configuration, even when the tilt stage 400 is operated to adjust the tilt of the lens OP, the image of the beam spot does not move greatly on the monitor 612. The tilt axes tx1 and tx2 of the tilt stage 400 are Compared with the configuration in which the lens OP is arranged away from the principal point position, the number of man-hours required for positioning the lens OP is significantly reduced.

  The tilt stage 400 includes a first tilt drive mechanism 430 that tilts the outer ring portion 412 with respect to the frame portion 420, and a second tilt drive mechanism 440 that tilts the sample stage 411 with respect to the outer ring portion 412. The first tilt drive mechanism 430 and the second tilt drive mechanism 440 have a first operation grip 431 and a second operation grip 441, respectively. When the first operation grip 431 is rotated, the outer ring portion 412 is inclined with respect to the frame portion 420. Further, when the second operation grip 441 is rotated, the sample stage 411 can be inclined with respect to the outer ring portion 412. Thus, by rotating the first operation grip 431 and the second operation grip 441, the sample stage 411 can be inclined in an arbitrary direction.

  The first operation grip 431 is fixed to an operation grip fixing plate 424 fixed to the rib plate 423 so as to be perpendicular to the rib plate 423. The first operation grip 431 incorporates a feed screw mechanism (not shown), and when the first operation grip 431 is rotated, the pin 431a provided at the tip of the first operation grip 431 can be advanced and retracted. ing. The advancing / retreating direction of the pin 431a is a direction orthogonal to both the vertical axis and the inclination axis of the outer ring portion 412 (the axis connecting the pin holes 412b and 412d of the outer ring portion 412) tx1 (FIGS. 4 and 5).

  A first arm 432 is disposed near the tip of the pin 431a. The first arm 432 is an L-shaped plate-like member, one end of which is in contact with the tip of the pin 431a, and the other end is fixed to the outer ring portion 412 (FIG. 6). In addition, a coil spring 433 is attached between the first arm 432 and the fixed plate 421 to urge the first arm 432 in a direction in which the first arm 432 is brought into contact with the tip of the pin 431a (FIGS. 5 and 6). Since the first arm 432 is always in contact with the tip of the pin 431a, when the pin 431a is advanced and retracted by rotating the first operation grip 431, the tip of the first arm 432 (contacts with the pin 431a). The portion) moves as the pin 431a advances and retreats, whereby the first arm 432 and the outer ring portion 412 swing around the inclination axis tx1 of the outer ring portion 412 and the outer ring portion 412 tilts.

  The second operation grip 441 is fixed to the rib plate 423. The second operation grip 441 has a built-in feed screw mechanism (not shown), and when the second operation grip 441 is rotated, the pin 441a provided at the tip of the second operation grip 441 can be advanced and retracted. (FIGS. 5 and 6). The advancing / retreating direction of the pin 441a is a direction parallel to the inclined axis of the outer ring portion 412 (axis connecting the pin holes 412b and 412d of the outer ring portion 412) tx1.

  The tip of the pin 441a is in contact with one end of a relay pin 442 that is arranged so that the advance / retreat direction of the pin 441a is the axial direction. The movement direction of the relay pin 442 is limited only to the axial direction of the relay pin 442 (that is, the forward / backward direction of the pin 441a) by the bearing 443. A second arm 444 is disposed near the other end of the relay pin 442. The second arm 444 is connected to the sample table 411 via a connection mechanism 450 described later. In addition, a coil spring 445 is attached between the coupling mechanism 450 and the first arm 432 to urge the second arm 444 in a direction in which the second arm 444 contacts the other end of the relay pin 442 (FIGS. 5 and 6). . The second arm 444 always contacts the other end of the relay pin 442, and one end of the relay pin 442 always contacts the tip of the pin 441a of the second operation grip 441. When the pin 441a is advanced and retracted by rotating it, the tip of the second arm 442 (the portion in contact with the relay pin 442) moves as the pin 441a advances and retreats, whereby the second arm 444 and the coupling mechanism 450 are moved. The sample stage 411 swings around the tilt axis tx2 of the sample stage 411, and the sample stage 411 tilts.

  The configuration of the coupling mechanism 450 will be described below. As shown in FIGS. 5 and 6, the connection mechanism 450 includes a connection block 451, a connection pin 452, a guide bar 453, and a compression coil spring 454. The connection block 451 is a rectangular parallelepiped block fixed to the sample table 411.

  As shown in FIGS. 5 and 6, the second arm 444 includes a first plate portion 444a that is substantially parallel to the outer ring portion 412 (that is, extends in a direction parallel to the tilt axis tx2 of the sample table 411), This is an L-shaped arm integrally formed with a second plate portion 444b extending in a direction along the fixed plate 421 (vertical direction in FIG. 5). The relay pin 442 is in contact with the second plate portion 444b at the tip of the second plate portion 444b (that is, the portion distal to the first plate portion 444a).

  The connecting block 451 and the first plate portion 444a of the second arm 444 are rotated around an axis parallel to the inclined axis tx1 of the outer ring portion 412 with respect to the connecting block 451 by the connecting pin 452. It is connected as possible.

  Further, the first plate portion 444a of the second arm 444 has a through hole 444c that is perforated along a substantially vertical direction in FIG. The guide bar 453 is a rod-like member fixed to the sample table 411 so as to extend in a direction perpendicular to the surface of the sample table 411, and is disposed so as to pass through the through hole 444c of the first plate portion 444a. The compression coil spring 454 is attached to the guide bar 453 so that the guide bar 453 passes through the compression coil spring 454. A head 453 a having a larger diameter than the outer diameter of the compression coil spring 454 is formed at the tip of the guide bar 453. The diameter of most of the through-hole 444c is formed larger than the outer diameter of the compression coil spring 454, but the diameter of the part of the through-hole 444c is the main part of the guide bar 453 (except for the head 453a). The protrusion 444d which is larger than the outer diameter of the compression coil spring 454 is provided (FIG. 5). The both ends of the compression coil spring 454 are held between the head portion 453a of the guide bar 453 and the protruding portion 444d formed in the through hole 444c of the first plate portion 444a of the second arm 444. It has become.

  Since the compression coil spring 454 is held between the guide bar 453 and the second arm 444 as described above, the compression coil spring 454 repels the first plate portion 444a of the second arm 444 with the sample. It is energized in the direction toward the table 411. Here, the through hole 444c is formed at a position that is more proximal than the connection pin 452 with respect to the second plate portion 444b of the second arm 444. Therefore, the second arm 444 is biased in the clockwise direction in FIG. 5 around the connecting pin 452, that is, in the direction in which the tip of the second plate portion 444 b of the second arm 444 is directed toward the fixing plate 421. Become.

  7 is a cross-sectional view taken along the line AA of FIG. 4 showing a state in which the sample table 411 and the outer ring portion 412 are tilted counterclockwise in FIG. 5 by the first tilt drive mechanism 430 from the state of FIG. 8 is a cross-sectional view taken along the line AA of FIG. 4 showing a state in which the sample table 411 and the outer ring portion 412 are tilted counterclockwise in FIG. 5 by the first tilt drive mechanism 430 from the state of FIG. . As shown in FIGS. 5 to 8, at the tip of the second plate portion 444 b of the second arm 444, a roller 446 that can roll along the fixed plate 421 along the axial direction (advancing / retreating direction) of the relay pin 442. Is supported.

  As described above, the second arm 444 is attached in the direction in which the distal end portion of the second plate portion 444b is directed to the fixed plate 421 (that is, the roller 446 is directed to the fixed plate 421) by the repulsive force of the compression coil spring 454. It is energized. Therefore, as shown in FIGS. 5, 7, and 8, the roller 446 is fixed even when the sample table 411 and the outer ring portion 412 are tilted around the tilt axis tx <b> 1 of the outer ring portion 412 by the first tilt drive mechanism 430. The state of contact with the plate 421 is maintained. According to the present embodiment, as described above, the roller 446 is pressed against and held by the fixed plate 421, so that the position shift of the distal end portion of the second plate portion 444 b of the second arm 444 accompanying the inclination of the outer ring portion 412. However, the contact between the relay pin 442 and the second arm 444 does not come off due to the inclination of the outer ring portion 412.

  Further, as described above, since the second arm 444 is connected to the sample table 411 via the connection pin 452 and the connection block 451, the second operation grip 441 of the second tilt driving unit 440 is operated. The sample stage 411 can be tilted around the tilt axis tx2.

  As described above, according to this embodiment, the first operation grip 431 of the first tilt drive mechanism 430 and the second operation grip 441 of the second tilt drive mechanism 440 are operated to move the sample table 411 with the tilt axes tx1 and tx2. Can be tilted around. Since both the first operation grip 431 and the second operation grip 441 are fixed integrally with the fixed plate 421, the second operation grip 441 is different from the conventional configuration in which the outer operation portion 412 swings integrally. When the second grip 441 is operated, the second grip 441 itself cannot be swung around the tilt axis tx1, and an unintended tilt of the sample table 411 does not occur.

  In the present embodiment, the roller 446 is interposed between the second plate portion 444b of the second arm 444 and the fixed plate 421, so that the second arm 444 can be smoothly swung. . However, the present invention is not limited to the above-described configuration, and a member for smoothly swinging the second arm 444 (for example, a resin material having a low coefficient of friction such as fluororesin) is used instead of the roller 446. It is good also as a structure interposed between the 2 plate part 444b and the fixed plate 421.

DESCRIPTION OF SYMBOLS 1 Spot measuring device 400 Inclination stage 411 Sample stand 412 Outer ring part 420 Frame part 430 1st inclination drive mechanism 431 1st operation grip 432 1st arm 440 2nd inclination drive mechanism 441 2nd operation grip 442 Relay pin 446 Roller 450 Connection mechanism
451 Connection block 452 Connection pin 453 Guide bar 454 Compression coil spring

Claims (5)

A lens position adjusting mechanism for adjusting the position of the lens while holding the lens,
Frame,
An outer ring portion rotatable about a first axis with respect to the frame;
A sample stage that is rotatable about a second axis perpendicular to the first axis with respect to the outer ring portion, and on which the lens is held;
A first arm connected to the outer ring portion and rotating the outer ring portion around a first axis;
A second arm rotatably connected to the sample stage about a third axis parallel to the first axis and rotating the sample stage about a second axis;
First and second driving means comprising a fixed portion fixed to the frame, and a movable portion that advances and retreats relative to the fixed portion;
First biasing means for biasing the first arm so that the first arm comes into contact with the movable portion of the first driving means;
Second urging means for urging the second arm so that the second arm comes into contact with the movable part of the second driving means;
A lens position adjusting mechanism comprising: a third urging unit that urges the second arm about the third axis so that a distal end portion of the second arm abuts the frame.   Friction reducing means for reducing a friction force acting between the frame and the distal end portion of the second arm is provided between the frame and the distal end portion of the second arm. The lens position adjusting mechanism according to claim 1.   3. The lens position adjusting mechanism according to claim 2, wherein the friction reducing means is a roller that is provided at a distal end portion of the second arm and rolls along the frame. The sample stage has a plate-like part for holding a lens, and a connection block fixed to the lower surface of the plate-like part of the sample stage,
4. The lens position adjusting mechanism according to claim 1, wherein the connection block is connected to the second arm so as to be rotatable around the third axis. 5. The sample stage is fixed to the plate-like portion of the sample stage, and has a guide bar extending perpendicularly to the lower surface of the plate-like part of the sample stage;
The second arm has a plate-like portion formed with a through hole through which the guide bar is inserted,
The third urging means is a coil spring that is passed through the guide bar and is held between a tip portion of the guide bar and a plate-like portion of the second arm. The lens position adjusting mechanism according to claim 4.

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