Method for machining optical element

Abstract

To provide a method for machining an optical element capable of highly accurately forming the optical element from a transparent prism workpiece such as a glass column.SOLUTION: A method for machining an optical element includes: a frame unit preparing step of preparing a frame unit 2 in which an adhesive tape 6 is disposed on a frame 4; a cutting apparatus preparing step; an attaching step of attaching a transparent prism workpiece 52 to the adhesive tape 6 of the frame unit 2; a positioning step of positioning a blade edge of a cutter blade 36 at a depth exceeding a half thickness of the prism workpiece 52; a first half-cut groove forming step of forming a first half-cut groove 54 in a first surface 52a of the prism workpiece 52; a second half-cut groove forming step of positioning, so as to face upward, a second surface 52b adjacent to the first surface 52a portion, and then forming a second half-cut groove 56 that coincides with the first half-cut groove 54; and a third half-cut groove forming step of positioning, so as to face upward, a third surface 52c adjacent to the second surface 52b, and then forming a third half-cut groove 58 that coincides with the second half-cut groove 56.SELECTED DRAWING: Figure 8

Description

Technical Field

[0001] The present invention relates to a method for processing optical elements.

Background Art

[0002] A wafer on which a plurality of devices such as ICs and LSIs are partitioned by a division planned line and formed on the surface is divided into individual device chips by a cutting device, and each divided device chip is used for electric devices such as mobile phones and personal computers.

[0003] Also, when cutting out optical elements such as prisms, polarizing plates, diffraction gratings, and LEDs, a cutting device is used (see, for example, Patent Document 1). For example, when generating a cubic prism from a glass column, when the thickness of the glass column exceeds the allowable value of the cutting depth of the cutting blade, a half cut is made from the surface of the glass column, and then a half cut is made from the back surface of the glass column to generate a cubic prism from the glass column.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, there are cases where the position of the half cut formed from the surface of the glass column and the position of the half cut formed from the back surface of the glass column are displaced. In such a case, there is a problem that a high-precision cubic prism cannot be generated.

[0006] An object of the present invention is to provide a method for processing an optical element capable of highly accurately generating an optical element from a prismatic workpiece of a transparent body such as a glass column.

Means for Solving the Problems

[0007] According to the present invention, there is provided a method for processing the following optical element to solve the above problems. That is, "A method for processing an optical element, comprising: a frame unit preparation step of preparing a frame unit in which an adhesive tape is disposed on a frame having an opening at the center; a cutting device preparation step of preparing a cutting device including a chuck table for holding a workpiece, a cutting means rotatably mounted with a cutting blade having a cutting edge for cutting the workpiece held on the chuck table on an outer periphery thereof, an X-axis feed means for relatively cutting and feeding the chuck table and the cutting means in the X-axis direction, and a Y-axis feed means for relatively indexing and feeding the chuck table and the cutting means in a Y-axis direction orthogonal to the X-axis direction; an adhering step of adhering a prismatic workpiece of a transparent body to the adhesive tape of the opening of the frame unit; an positioning step of positioning the longitudinal direction of the prismatic workpiece in the Y-axis direction, holding the frame unit on the chuck table, positioning the cutting blade at a required position in the longitudinal direction of the prismatic workpiece, and positioning the cutting edge of the cutting blade at a depth exceeding 1 / 2 of the thickness of the prismatic workpiece; a first half-cut groove forming step of operating the X-axis feed means to form a first half-cut groove in a first surface of the prismatic workpiece; a second half-cut groove forming step of rolling the prismatic workpiece in the X-axis direction to position an upper second surface adjacent to the first surface and forming a second half-cut groove corresponding to the first half-cut groove; a third half-cut groove forming step of rolling the prismatic workpiece in the X-axis direction to position an upper third surface adjacent to the second surface and forming a third half-cut groove corresponding to the second half-cut groove", which is a method for processing an optical element.

[0008] The optical element is preferably a cubic prism.

Advantages of the Invention

[0009] The processing method of the optical element of the present invention is as follows: A frame unit preparation step of preparing a frame unit in which an adhesive tape is disposed on a frame having an opening at the center; A chuck table for holding a workpiece to be processed, a cutting means rotatably mounted with a cutting blade having a cutting edge for cutting the workpiece held on the chuck table on its outer periphery, an X-axis feed means for relatively cutting and feeding the chuck table and the cutting means in the X-axis direction, and a Y-axis feed means for relatively indexing and feeding the chuck table and the cutting means in the Y-axis direction orthogonal to the X-axis direction, and a cutting apparatus preparation step of preparing a cutting apparatus including the above; An adhering step of adhering a prismatic workpiece of a transparent body to the adhesive tape of the opening of the frame unit; An positioning step of positioning the longitudinal direction of the prismatic workpiece in the Y-axis direction, holding the frame unit on the chuck table, positioning the cutting blade at a required position in the longitudinal direction of the prismatic workpiece, and positioning the cutting edge of the cutting blade at a depth exceeding 1 / 2 of the thickness of the prismatic workpiece; A first half-cut groove forming step of operating the X-axis feed means to form a first half-cut groove on a first surface of the prismatic workpiece; A second half-cut groove forming step of rolling the prismatic workpiece in the X-axis direction to position an upper second surface adjacent to the first surface and forming a second half-cut groove that coincides with the first half-cut groove; A third half-cut groove forming step of rolling the prismatic workpiece in the X-axis direction to position an upper third surface adjacent to the second surface and forming a third half-cut groove that coincides with the second half-cut groove. Since the first, second, and third half-cut grooves are connected without being displaced, according to the present invention, an optical element can be generated with high precision from a prismatic workpiece of a transparent body such as a glass column.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Embodiments for Carrying Out the Invention

[0011] Hereinafter, a preferred embodiment of a method for processing an optical element according to the present invention will be described with reference to the drawings.

[0012] (Frame unit preparation step) In this embodiment, first, a frame unit preparation step is performed to prepare a frame unit in which an adhesive tape is disposed on a frame having an opening at the center. In the frame unit preparation step, for example, a frame unit 2 as shown in FIG. 1 may be prepared. This frame unit 2 has an annular frame 4 having an opening 4a at the center and a circular adhesive tape 6 attached to the inner peripheral edge of the frame 4.

[0013] (Cutting device preparation step) Also, a cutting device preparation step is performed to prepare a cutting device including a chuck table for holding a workpiece, a cutting means rotatably mounted with a cutting blade having a cutting edge for cutting the workpiece held by the chuck table on its outer periphery, an X-axis feed means for relatively cutting and feeding the chuck table and the cutting means in the X-axis direction, and a Y-axis feed means for relatively indexing and feeding the chuck table and the cutting means in the Y-axis direction orthogonal to the X-axis direction. The cutting device preparation step may be performed before or after the frame unit preparation step.

[0014] (Cutting device) In the cutting device preparation step, for example, the cutting device 8 shown in FIG. 2 can be prepared. The cutting device 8 includes a chuck table 10, a cutting means 12, an X-axis feed means 14, and a Y-axis feed means 16.

[0015] (Chuck table 10) A circular suction chuck 18 is arranged at the upper end portion of the chuck table 10. The suction chuck 18 is formed of a porous member such as porous ceramics. Further, the suction chuck 18 is connected to a suction means (not shown). And in the chuck table 10, a suction force is generated on the upper surface of the suction chuck 18 by the suction means, and the workpiece placed on the upper surface of the chuck table 10 is suction-held. Also, a plurality of clamps 20 are arranged at intervals in the circumferential direction on the periphery of the chuck table 10.

[0016] As shown in FIG. 2, the chuck table 10 is rotatably mounted on the upper end of a support column 22. The chuck table 10 is rotated by a motor (not shown) built in the support column 22. The support column 22 is fixed to the upper surface of an X-axis movable plate 24. The X-axis movable plate 24 is supported movably in the X-axis direction on the upper surface of a base 26 of the cutting device 8.

[0017] In addition, in FIG. 1, the X, Y, and Z axis directions are indicated by arrows X, Y, and Z, respectively. The Y axis direction is perpendicular to the X axis direction, and the Z axis direction is the vertical direction perpendicular to the X axis direction and the Y axis direction. The XY plane defined by the X axis direction and the Y axis direction is substantially horizontal.

[0018] (Cutting means 12) The cutting means 12 includes a Y-axis movable body 28 supported on the upper surface of the base 26 so as to be movable in the Y-axis direction, and a Z-axis movable body 30 supported by the Y-axis movable body 28 so as to be movable in the Z-axis direction. A spindle housing 32 extending in the Y-axis direction is attached to the Z-axis movable body 30. A spindle 34 extending in the Y-axis direction is rotatably supported by the spindle housing 32. An annular cutting blade 36 is fixed to the tip of the spindle 34. A cutting edge for cutting the workpiece held on the chuck table 10 is provided on the outer periphery of the cutting blade 36. Further, an imaging means 38 is arranged at a distance from the cutting blade 36 in the X-axis direction, and the imaging means 38 is supported by the spindle housing 32.

[0019] (X-axis feed means 14) The X-axis feed means 14 has a ball screw 40 connected to the X-axis movable plate 24 and extending in the X-axis direction, and a motor 42 for rotating the ball screw 40. The X-axis feed means 14 converts the rotational motion of the motor 42 into a linear motion by the ball screw 40 and transmits it to the X-axis movable plate 24, and moves the X-axis movable plate 24 in the X-axis direction along a pair of X-axis guide rails 26a provided on the base 26. Thereby, the chuck table 10 is fed in the X-axis direction for cutting with respect to the cutting means 12.

[0020] (Y-axis feed means 16) The Y-axis feed means 16 has a ball screw 44 that is connected to the Y-axis movable body 28 and extends in the Y-axis direction, and a motor 46 that rotates the ball screw 44. The Y-axis feed means 16 converts the rotational motion of the motor 46 into linear motion by the ball screw 44 and transmits it to the Y-axis movable body 28, and moves the Y-axis movable body 28 in the Y-axis direction along a pair of Y-axis guide rails 26b provided on the base 26. As a result, the cutting blade 36 of the cutting means 12 is fed in the Y-axis direction with respect to the chuck table 10.

[0021] Further, the cutting device 8 includes a Z-axis feed means 48 that relatively feeds the chuck table 10 and the cutting means 12 in the Z-axis direction. The Z-axis feed means 48 has a ball screw (not shown) that is connected to the Z-axis movable body 30 and extends in the Z-axis direction, and a motor 50 that rotates this ball screw. The Z-axis feed means 48 converts the rotational motion of the motor 50 into linear motion by the ball screw and transmits it to the Z-axis movable body 30, and moves the Z-axis movable body 30 in the Z-axis direction along a pair of Z-axis guide rails 28a (only one is shown) attached to the Y-axis movable body 28. As a result, the cutting blade 36 of the cutting means 12 is fed in the Z-axis direction with respect to the chuck table 10.

[0022] (Sticking process) After performing the frame unit preparation process and the cutting device preparation process, as shown in FIG. 3, a sticking process is performed in which a prismatic workpiece 52 (square prism workpiece) of a transparent body is stuck to the adhesive tape 6 in the opening 4a of the frame unit 2. In a state where the prismatic workpiece 52 is stuck to the adhesive tape 6, the upper surface of the prismatic workpiece 52 is defined as the first surface 52a, the surface adjacent to the first surface 52a is defined as the second surface 52b, and the surface adjacent to the second surface 52b (the surface on the opposite side of the first surface 52a) is defined as the third surface 52c.

[0023] (Positioning process) After performing the sticking process, the frame unit 2 is held on the chuck table 10 with the longitudinal direction of the square column workpiece 52 positioned in the Y-axis direction, and the cutting blade 36 is positioned at a required position in the longitudinal direction of the square column workpiece 52, and a positioning process is performed in which the cutting edge of the cutting blade 36 is positioned at a depth exceeding 1 / 2 of the thickness of the square column workpiece 52.

[0024] In the positioning process, first, the frame unit 2 is held on the chuck table 10. At this time, first, the square column workpiece 52 is placed on the upper surface of the chuck table 10 via the adhesive tape 6. Next, the suction means is operated to generate a suction force on the upper surface of the suction chuck 18, and the square column workpiece 52 is suction-held by the chuck table 10. Also, the frame 4 is fixed by a plurality of clamps 20. In this way, the frame unit 2 is held on the chuck table 10.

[0025] After the frame unit 2 is held on the chuck table 10, the longitudinal direction of the square column workpiece 52 is positioned in the Y-axis direction. At this time, first, the chuck table 10 is moved in the X-axis direction by the X-axis feed means 14, and the square column workpiece 52 is positioned below the imaging means 38. Next, the square column workpiece 52 is imaged by the imaging means 38. Then, based on the image of the square column workpiece 52 imaged by the imaging means 38, the chuck table 10 is appropriately rotated to position the longitudinal direction of the square column workpiece 52 in the Y-axis direction.

[0026] After the longitudinal direction of the square column workpiece 52 is positioned in the Y-axis direction, the cutting blade 36 is positioned at a required position. Specifically, the Y-axis movable body 28 is moved in the Y-axis direction by the Y-axis feed means 16, and as shown in Fig. 4(a), the cutting blade 36 is positioned at a required position in the longitudinal direction of the square column workpiece 52. Also, the Z-axis movable body 30 is moved in the Z-axis direction by the Z-axis feed means 48, and as shown in Fig. 4(b), the cutting edge of the cutting blade 36 is positioned at a depth exceeding 1 / 2 of the thickness T of the square column workpiece 52. That is, the lower end of the cutting edge of the cutting blade 36 is positioned at a position lower than half (T / 2) of the thickness T of the square column workpiece 52.

[0027] (First half-cut groove forming step) After performing the positioning step, a first half-cut groove forming step is performed in which the X-axis feed means 14 is operated to form a first half-cut groove in the first surface 52a (the upper surface of the prism workpiece 52) of the prism workpiece 52.

[0028] In the first half-cut groove forming step, first, the cutting blade 36 is rotated in the direction indicated by the arrow R in FIG. 4(b). Then, by operating the X-axis feed means 14 and moving the chuck table 10 in the direction indicated by the arrow X1 in FIG. 4(b), the cutting edge of the cutting blade 36 is cut into the first surface 52a (the upper surface of the prism workpiece 52) of the prism workpiece 52. Also, cutting water is supplied to the portion where the cutting edge of the cutting blade 36 is cut in. As a result, as shown in FIG. 5, a first half-cut groove 54 having a depth exceeding 1 / 2 of the thickness T of the prism workpiece 52 is formed in the first surface 52a of the prism workpiece 52. In FIG. 5(b), the first half-cut groove 54 is shown by hatching.

[0029] (Second half-cut groove forming step) After performing the first half-cut groove forming step, the prism workpiece 52 is rolled in the X-axis direction to position the second surface 52b adjacent to the first surface 52a upward, and a second half-cut groove forming step is performed to form a second half-cut groove that coincides with the first half-cut groove 54.

[0030] In the second half-cut groove forming step, as shown in FIG. 6, the prism workpiece 52 is rolled in the X-axis direction to position the second surface 52b upward. That is, the prism workpiece 52 is rolled in the X-axis direction on the adhesive tape 6 and rotated 90 degrees to position the second surface 52b upward. Note that the rolling of the prism workpiece 52 can be performed without releasing the suction force of the suction chuck 18.

[0031] When the second surface 52b is positioned upward, position the first half-cut groove 54 in the X-axis direction. In this case, first, move the chuck table 10 in the X-axis direction by the X-axis feed means 14 to position the prism workpiece 52 below the imaging means 38. Next, image the prism workpiece 52 by the imaging means 38. Then, based on the image of the prism workpiece 52 imaged by the imaging means 38, appropriately rotate the chuck table 10 to position the first half-cut groove 54, a part of which is exposed on the second surface 52b, in the X-axis direction.

[0032] When the first half-cut groove 54 is positioned in the X-axis direction, position the cutting blade 36 at the required position. Specifically, move the Y-axis movable body 28 in the Y-axis direction by the Y-axis feed means 16 to make the Y-axis direction position of the first half-cut groove 54 coincide with the Y-axis direction position of the cutting blade 36 as shown in FIG. 6. Also, move the Z-axis movable body 30 in the Z-axis direction by the Z-axis feed means 48 to position the cutting edge of the cutting blade 36 at a depth exceeding 1 / 2 of the thickness T of the prism workpiece 52.

[0033] When the cutting blade 36 is positioned at the required position, form a second half-cut groove corresponding to the first half-cut groove 54 in the prism workpiece 52. In this case, first, rotate the cutting blade 36 in the direction indicated by the arrow R in FIG. 6. Then, operate the X-axis feed means 14 to move the chuck table 10 in the direction indicated by the arrow X1 to cut the cutting edge of the cutting blade 36 into the second surface 52b of the prism workpiece 52. Also, supply cutting fluid to the portion where the cutting edge of the cutting blade 36 is cut. Thereby, as shown in FIG. 7(a), form a second half-cut groove 56 with a depth exceeding 1 / 2 of the thickness T of the prism workpiece 52 on the second surface 52b of the prism workpiece 52. In FIG. 7(b), the first and second half-cut grooves 54 and 56 are shown by hatching.

[0034] In the second half cut groove forming step, the second half cut groove 56 is formed so as to match the first half cut groove 54 partially exposed on the second surface 52b. Thus, the first half cut groove 54 and the second half cut groove 56 are connected without being displaced from each other.

[0035] (Third half cut groove forming step) After performing the second half cut groove forming step, the prism workpiece 52 is rolled in the X-axis direction to position the third surface 52c adjacent to the second surface 52b upward, and a third half cut groove matching the second half cut groove 56 is formed. The third half cut groove forming step is performed.

[0036] In the third half cut groove forming step, as shown in Fig. 8(a), the prism workpiece 52 is rolled in the X-axis direction to position the third surface 52c upward. That is, the prism workpiece 52 is rolled on the adhesive tape 6 in the X-axis direction and rotated by 90 degrees to position the third surface 52c upward.

[0037] After positioning the third surface 52c upward, the second half cut groove 56 is positioned in the X-axis direction. At this time, first, the chuck table 10 is moved in the X-axis direction by the X-axis feed means 14 to position the prism workpiece 52 below the imaging means 38. Next, the prism workpiece 52 is imaged by the imaging means 38. Then, based on the image of the prism workpiece 52 captured by the imaging means 38, the chuck table 10 is appropriately rotated to position the second half cut groove 56 partially exposed on the third surface 52c in the X-axis direction.

[0038] After positioning the second half cut groove 56 in the X-axis direction, the cutting blade 36 is positioned at the required position. Specifically, the Y-axis movable body 28 is moved in the Y-axis direction by the Y-axis feed means 16 to match the Y-axis direction position of the second half cut groove 56 and the Y-axis direction position of the cutting blade 36 as shown in Fig. 8(a). Also, the Z-axis movable body 30 is moved in the Z-axis direction by the Z-axis feed means 48 to position the cutting edge of the cutting blade 36 at a depth exceeding 1 / 2 of the thickness T of the prism workpiece 52.

[0039] Once the cutting blade 36 is positioned at the required position, a third half-cut groove corresponding to the second half-cut groove 56 is formed in the prismatic workpiece 52. At this time, first, the cutting blade 36 is rotated in the direction indicated by the arrow R in FIG. 8(a). Then, the X-axis feeding means 14 is operated to move the chuck table 10 in the direction indicated by the arrow X1, so that the cutting edge of the cutting blade 36 is cut into the third surface 52c of the prismatic workpiece 52. In addition, cutting water is supplied to the portion where the cutting edge of the cutting blade 36 is cut in. As a result, as shown in FIG. 8(b), a third half-cut groove 58 having a depth exceeding 1 / 2 of the thickness T of the prismatic workpiece 52 is formed in the third surface 52c of the prismatic workpiece 52. As a result, an optical element 60 separated from the prismatic workpiece 52 by the first, second, and third half-cut grooves 54, 56, and 58 is generated. Examples of the generated optical element 60 include a cubic prism.

[0040] In the third half-cut groove forming step, since the third half-cut groove 58 is formed so as to coincide with the second half-cut groove 56 partially exposed on the third surface 52c, the first, second, and third half-cut grooves 54, 56, and 58 are connected without being displaced. Therefore, according to the present embodiment, an optical element 60 such as a cubic prism can be generated with high precision from a prismatic workpiece 52 of a transparent body such as a glass column.

Explanation of Reference Numerals

[0041] 2: Frame unit 4: Frame 4a: Opening 6: Adhesive tape 8: Cutting device 10: Chuck table 12: Cutting means 14: X-axis feeding means 16: Y-axis feeding means 36: Cutting blade 52: Prismatic workpiece 52a: First surface of the prismatic workpiece 52b: Second surface of the prismatic workpiece 52c: The third surface of the corner post workpiece 54: The first half-cut groove 56: The second half-cut groove 58: The third half-cut groove

Claims

1. A method for processing an optical element, comprising: a frame unit preparation step of preparing a frame unit in which an adhesive tape is disposed on a frame having an opening at the center; a cutting device preparation step of preparing a cutting device including a chuck table for holding a workpiece, a cutting means rotatably mounted with a cutting blade having a cutting edge for cutting the workpiece held on the chuck table on an outer periphery thereof, an X-axis feed means for relatively cutting and feeding the chuck table and the cutting means in the X-axis direction, and a Y-axis feed means for relatively indexing and feeding the chuck table and the cutting means in a Y-axis direction orthogonal to the X-axis direction; an attaching step of attaching a prismatic workpiece of a transparent body to the adhesive tape of the opening of the frame unit; an aligning step of positioning the longitudinal direction of the prismatic workpiece in the Y-axis direction, holding the frame unit on the chuck table, positioning the cutting blade at a required position in the longitudinal direction of the prismatic workpiece, and positioning the cutting edge of the cutting blade at a depth exceeding 1 / 2 of the thickness of the prismatic workpiece; a first half-cut groove forming step of operating the X-axis feed means to form a first half-cut groove in a first surface of the prismatic workpiece; a second half-cut groove forming step of rolling the prismatic workpiece in the X-axis direction to position an upper second surface adjacent to the first surface and forming a second half-cut groove that coincides with the first half-cut groove; a third half-cut groove forming step of rolling the prismatic workpiece in the X-axis direction to position an upper third surface adjacent to the second surface and forming a third half-cut groove that coincides with the second half-cut groove. A method for processing an optical element.

2. The method for processing an optical element according to claim 1, wherein the optical element is a cubic prism.

Images