JPH0596911U - Optical element adjustment device - Google Patents

Abstract

(57) [Abstract] [Purpose] To prevent displacement of the prism holder when fixing the positioned prism holder to the base member with screws. [Structure] The right-side screw 40 and the left-side screw 41 are formed so that the rotation directions at the time of tightening are opposite to each other. When the screw 40 on the right side is rotated clockwise and the screw 41 on the left side is rotated counterclockwise, respectively, a force f1 that acts to shift the screw 40 on the right side in the counterclockwise direction opposite to the tightening direction acts, A force f2 that acts to shift the left screw 41 in the clockwise direction is applied. However, the moment in the arrow G1 direction acting on the prism holder 30 by the force f1 is canceled by the moment in the arrow G2 direction acting on the prism holder 30 by the force f2. Therefore, a moment to rotate the prism holder 30 about the boss portion 31 does not occur.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an optical element adjusting device used as a mechanism for correcting an optical path deviation in an optical information recording / reproducing device, for example.

[0002]

[Prior Art]

 Conventionally, as an optical element adjusting device, there is a device that corrects an optical path shift caused by variations in processing accuracy of optical components by adjusting the direction of a reflecting surface of a reflecting prism. As shown in FIG. 4, the reflecting prism 50 is fixed to the upper surface of the prism holder 60 such that the center of the reflecting surface P coincides with the center of the boss portion 61 provided on the lower surface of the prism holder 60. The prism holder 60 has a boss portion 61 fitted and inserted into a base member (not shown), and is rotatably supported by the base member around the boss portion 61. The prism holder 60 is positioned on the base member so that the reflection surface P of the reflection prism 50 faces a predetermined direction, and is fixed to the base member by two screws 70. Each of the screws 70 is formed as a right-hand screw, and is tightened by rotating clockwise and loosened by rotating counterclockwise. That is, the prism holder 60 is positioned on the base member so that the reflection prism 50 faces a predetermined direction with the screws 70 rotated counterclockwise and loosened, and then the screws 70 are rotated clockwise. Then, it is fixed to the base member by tightening.

[0003]

[Problems to be solved by the device]

 In the conventional optical element adjusting device described above, when the screws 70 are tightened while the prism holder 60 is positioned on the base member, all the screws 70 are right-handed screws and are rotated clockwise. Is rotated counterclockwise around the boss portion 61, and there is a problem in that it is displaced on the base member. That is, when each screw 70 is tightened in the clockwise direction, a stress that repels the tightening force is generated in the contact surface between each screw 70 and the prism holder 60, and each screw 70 is displaced in the counterclockwise direction opposite to the tightening direction. As the force f to do so, the force is distributed and acts on the outer circumference of the head of each screw 70. The sum of the moments of the force f that acts on each screw 70 is the moment in the direction of arrow D that attempts to rotate the prism holder 60 counterclockwise about the boss portion 61. Therefore, the prism holder 60 rotates counterclockwise with the boss portion 61 as the center, and is displaced from the positioned state. According to the present invention, when the positioned holder is fixed to the base member by the screw member, the moment of stress generated between the pair of screw member and the holder is measured by the other screw member and the holder of the pair. It is an object of the present invention to provide a highly reliable optical element adjusting device that cancels out due to a moment of stress generated between them and thereby does not cause displacement of the holder.

[0004]

[Means for Solving the Problems]

 The optical element adjusting device according to the present invention is such that the base member and the optical member fixed to the upper surface are positioned on the base member so that they are oriented in a predetermined direction, and are screwed to the base member. The holder is fixed to the screw member, and the pair of screw members are characterized in that the rotating directions at the time of tightening are opposite to each other.

[0005]

【Example】

 The present invention will be described below with reference to illustrated embodiments. 1 to 3 show the configuration of an optical element adjusting apparatus which is an embodiment of the present invention. In these figures, the reflection prism 10 is fixed to the upper surface 33 of a prism holder 30 which is supported on the base member 20 so as to be horizontally rotatable. The direction of the reflecting surface P of the reflecting prism 10 is adjusted by the rotation of the prism holder 30, and the deviation of the optical path caused by variations in the processing accuracy of optical components is corrected.

A reference hole 21 is formed in the base member 20 substantially at the center. The boss portion 31 of the prism holder 30 is fitted into the reference hole 21. Screw holes 22 and 23 are formed on both sides of the reference hole 21 in the base member 20 at substantially equal distances from the reference hole 21. Female screws are formed on the inner surfaces of the screw holes 22 and 23, and screws 40 and 41 are screwed into the female holes.

A cylindrical boss portion 31 is provided at a predetermined position on the lower surface 34 of the prism holder 30. The boss portion 31 is fitted into the reference hole 21 of the base member 20 so as to be rotatable in the circumferential direction, so that the prism holder 30 is rotatably supported on the base member 20.

The reflection prism 10 is fixed to the upper surface 33 of the prism holder 30. The fixed position of the reflection prism 10 is determined so that the center of the reflection surface P coincides with the central axis of the boss portion 31.

Long holes 32 are formed on both sides of the reflection prism 10 in the prism holder 30. A pair of left and right screws 40, 41 are fitted into each slot 32 via washers 42, 43 with play. The screws 40 and 41 fitted into the long holes 32 are screwed into the screw holes 22 and 23 of the base member 20, respectively, and fix the prism holder 30 at a predetermined position of the base member 20.

The screw 40 on the right side is formed as a right screw, and is rotated clockwise to be tightened, so that the prism holder 30 is sandwiched between the base member 20 and the head through the washer 42. Fixed to. Further, in the state where the prism holder 30 is rotated counterclockwise and loosened, rotation about the boss portion 31 of the prism holder 30 is allowed within a predetermined range by relatively moving in the elongated hole 32 of the prism holder 30. .

The left-hand screw 41 is formed as a left-hand screw, and is rotated counterclockwise and tightened so that the prism holder 30 is sandwiched between the head and the washer 43. It is fixed to the base member 20. Further, in the state where the prism holder 30 is rotated clockwise and loosened, the rotation around the boss portion 31 of the prism holder 30 is allowed within a predetermined range by relatively moving in the elongated hole 32 of the prism holder 30.

A U-shaped cutout portion 35 is provided at the left end portion of the prism holder 30. An adjusting tool (not shown) is fitted into the notch 35 when adjusting the direction of the reflecting surface P of the reflecting prism 10.

The operation of this embodiment will be described. When adjusting the direction of the reflection surface P of the reflection prism 10 to the right, for example, the right side screw 40 is turned counterclockwise to loosen it, and the left side screw 41 is turned clockwise to be loosened. The adjustment tool is fitted into the cutout portion 35. Then, this adjusting tool is moved in a diagonally upper left direction in FIG. As a result, the prism holder 30 is rotated clockwise around the boss portion 31 and positioned so that the reflecting surface P of the reflecting prism 10 is oriented in a predetermined direction.

After the positioning is completed, the screw 40 on the right side is turned clockwise and the screw 41 on the left side is turned counterclockwise to tighten the prism holder 30 to the base member 20. At this time, a stress repulsive to the tightening force is generated on the contact surface between the washer 42 of the right-hand screw 40 and the upper surface 33 of the prism holder 30, and the right-hand screw 40 may be displaced in the counterclockwise direction opposite to the tightening direction. As a force f1 (FIG. 2) to be applied, it acts on the outer circumference of the head of the right screw 40. Similarly, between the washer 43 of the left screw 41 and the upper surface 33 of the prism holder 30, a stress that repels the tightening force is generated, and the left screw 41 tries to shift in the clockwise direction opposite to the tightening direction. The force f2 (FIG. 2) acts on the outer circumference of the head of the left screw 41. However, since these forces f1 and f2 are forces in opposite directions to each other, the moment in the direction of arrow G1 (FIG. 2) acting on the prism holder 30 by the sum of the forces f1 acts on the prism holder 30 by the sum of the forces f2. It is offset by the moment in the direction of arrow G2 (Fig. 2). Therefore, a moment to rotate the prism holder 30 around the boss portion 31 does not occur.

As described above, according to the above-described embodiment, the left and right screws 40 and 41 are reverse screws to each other, that is, the rotation directions when the left and right screws 40 and 41 are tightened are opposite directions. Therefore, even if the screws 40 and 41 are tightened to fix the positioned prism holder 30 to the base member 20, the position of the prism holder 30 does not shift. Thereby, the orientation of the reflecting surface P of the reflecting prism 10, that is, the positioning / fixing on the base member 20 by the rotation of the prism holder 30 can be performed with high accuracy.

[0016]

[Effect of the device]

 As described above, according to the present invention, when the positioned holder is fixed to the base member by the screw member, the moment of stress generated between the one screw member and the holder forming the pair forms a pair. A highly reliable optical element adjusting device is obtained in which the stress generated between the other screw member and the holder cancels each other out, and thereby the position of the positioned holder is not displaced.

[Brief description of drawings]

FIG. 1 is a perspective view showing an optical element adjusting apparatus according to an embodiment of the present invention.

FIG. 2 is a plan view of the optical element adjustment device of FIG.

FIG. 3 is a cross-sectional view of the optical element adjustment device of FIG.

FIG. 4 is a plan view showing a conventional optical element adjusting device.

[Explanation of symbols]

 10 Reflective Prism (Optical Member) 20 Base Member 30 Prism Holder (Holder) 40 Right Screw (Screw Member) 41 Left Screw (Screw Member)

Claims (1)

[Scope of utility model registration request] 1. A holder in which a base member and an optical member fixed to an upper surface are positioned on the base member so as to have a predetermined orientation, and fixed to the base member by at least a pair of screw members screwed to the base member. And a pair of screw members having opposite rotation directions at the time of tightening.