JPH07235059A - Device for attaching photodetector for optical pickup - Google Patents

Abstract

PURPOSE:To prevent a photodetector from shifting from the position where adjustment in the directions of X, Y axes are ended when an attaching plate to which the photodetector is fixed, is fixed to an optical block base. CONSTITUTION:Projecting pieces 13a, 13b letting fit adjusting jigs, letting the attaching plate 9 displace to perform the position adjustment of the photodetector 7 in the directions of X, Y axes, are provided on a first plate surface of the side attached to the optical block base 1 making the bend of the attaching plate 9 with a rough U shaped section a boundary. Then, this device is constituted so that the first plate surface of the attaching plate 9 is pressed to the optical block base 1 by the adjusting jigs.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photodetector mounting device for mounting a photodetector provided in an optical pickup for performing signal reproduction or signal recording using a light beam on an optical block base.

[0002]

2. Description of the Related Art In an optical pickup for performing signal reproduction or signal recording by using a light beam on a signal recording medium such as a disc, a photodetector for receiving a light beam modulated on the signal surface of the signal recording medium. In order to adjust the focusing error signal indicating the focusing error of the light beam on the signal surface of the signal recording medium or to adjust the tracking error signal indicating the tracking error of the light beam with respect to the signal track of the signal recording medium. It is necessary to adjust the position of the photodetector by displacing the photodetector in the optical axis direction of the light beam or displacing it in the plane direction of the photodetector.

As a conventional optical pickup, for example, as disclosed in Japanese Patent Laid-Open No. 3-260915, an elastic body having a U-shaped cross section is used as a mounting plate for mounting a photodetector, and a bent portion of the mounting plate is used. There is known a device using a photodetector mounting device in which the photodetector is mounted on a plate surface on a side different from the plate surface side fixed to the optical block base.

In this photodetector mounting device, an unnecessary inclination of the photodetector is suppressed by adjusting the bending degree of the mounting plate so that the photodetector can be easily adjusted in the optical axis direction (Z-axis direction). Can be done.

[0005]

By the way, in the above-described photodetector mounting device, adjustment of the light beam received by the photodetector in the direction orthogonal to the optical axis direction (X, Y axis direction) is performed by the photodetection. This is done with the screws for fixing the mounting plate of the device to the optical block base loosened, and after the adjustment, tighten the screws to fix the photodetector in place. Therefore, in the photodetector mounting device, the screwing is performed in an unstable state where the mounting plate is not in contact with the optical block base, and when the screwing is performed, the mounting plate rotates and X,
There is a drawback that the adjustment in the Y-axis direction is easily misaligned.

[0006]

DISCLOSURE OF THE INVENTION The present invention is a photodetector mounting device for an optical pickup intended to solve the above-mentioned drawbacks, and is an optical device with a bending portion of a mounting plate having a substantially U-shaped cross section as a boundary. On the plate surface that is attached to the block base, Z
In addition to being cut and raised in the axial direction, there is provided a protruding piece into which an adjusting jig for displacing in the X and Y axis directions is fitted.

[0007]

According to the present invention, the projecting piece is projected in the Z-axis direction on the plate surface of the mounting plate that is mounted on the optical block base,
An adjustment jig is fitted to the protrusion to adjust the position of the photodetector in the X and Y axis directions, and at the same time, the plate surface is pressed against the optical block base by the adjustment jig during the adjustment. The mounting plate can be tightened with the screws in the closed position.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings. 1 is a side view showing an embodiment of the present invention, and FIG.
Is a front view thereof, and FIG. 3 is an exploded perspective view thereof.

In the figure, reference numeral 1 denotes an optical block base in which various optical elements constituting an optical pickup are incorporated. The optical block base 1 has a light beam (laser light).
Is used for dividing the optical path of the light beam that has passed through the diffraction grating 3 and the diffraction grating 3 that diffracts the light beam generated by the laser diode 2, and is used for focus control. A half mirror 4 made of a parallel plate for generating astigmatism, a reflection mirror 5 for bending the light beam reflected by the half mirror 4 in a direction orthogonal to the disk D surface, and the reflection mirror 5. The objective lens 6 for focusing the light beam reflected by the disc D on the signal surface of the disc D;
And a photodetector 7 that receives the light beam that has been modulated and reflected by the signal surface of (1) and has been transmitted through the half mirror 4.

Reference numeral 8 is a printed circuit board to which the photodetector 7 is soldered, and reference numeral 9 is a mounting plate formed by bending a metal plate made of phosphor bronze having high rigidity into a substantially U-shaped section.

The mounting plate 9 is arranged such that a first plate surface 9a on one side of the bent portion is abutted against the mounting surface 1a of the optical block base 1 and is formed on the first plate surface 9a. Fixed to the optical block base 1 by the first plate surface 9a by screwing fixing screws 12a and 12b into screw holes 11a and 11b formed in the optical block base 1 through the formed through holes 10a and 10b, respectively. To be done. Further, on the first plate surface 9a, projecting pieces 13a and 13b are formed by cutting and raising in the optical axis direction (Z-axis direction) of the light beam received by the photodetector 7 at two predetermined positions on the peripheral edge. Has been done.

On the other hand, dowels 14a and 14b are formed on the second plate surface 9b on the other side of the bent portion of the mounting plate 9 as a boundary, and the holes 15a of the printed circuit board 8 to which the dowels 14a and 14b correspond respectively. , 15b, the printed circuit board 8 is set to the mounting position, and the second position of the mounting plate 9 is set.
It is attached to the plate surface 9b.

An adjusting screw 16 having a sharp tip is screwed into the second plate surface 9b on the side opposite to the bent portion of the mounting plate 9, and the tip of the adjusting screw 16 contacts the first plate surface 9a. It is touched. Therefore, the adjusting screw 16 is rotated to adjust the screwing degree of the adjusting screw 16 to the second plate surface 9b to adjust the bending rate of the bent portion, thereby adjusting the position of the photodetector 7 in the Z-axis direction. It can be done easily. That is, when the adjusting screw 16 is tightened, the second plate surface 9b is displaced toward the first plate surface 9a, and when the adjusting screw 16 is loosened, the second plate surface 9b is reversed. Is displaced in the direction away from the first plate surface 9a, the Z of the photodetector 7 attached to the second plate surface 9b via the printed circuit board 8 is removed.
It is possible to adjust the position in the axial direction.

Next, adjustment in the directions (X and Y axis directions) orthogonal to the optical axis direction of the light beam received by the photodetector 7 will be described. For adjustment of the photodetector 7 in the X and Y axis directions, as shown in FIG. 3, the jig 1 having insertion holes 17a and 17b having shapes corresponding to the dowels 14a and 14b, respectively, is formed at the tip.
8a and 18b are used.

The jigs 18a and 18b have insertion holes 17
The first plate surface 9a of the mounting plate 9 is pressed against the optical block base 1 with the dowels 14a and 14b fitted to the a and 17b, respectively, and the mounting plate 9 is rotated by rotating the two simultaneously. The mounting plate 9
Displace in the X and Y axis directions. Therefore, the mounting plate 9
The photodetector 7 is displaced in the X and Y axis directions with the rotation of
The photodetector 7 can be adjusted in the X and Y axis directions. Then, when this adjustment is completed, the fixing screw 12
The mounting plates 9 are fixed to the optical block base 1 by tightening a and 12b. That is, since the mounting plate 9 is pressed against the optical block base 1 by the first plate surface 9a by the jigs 18a and 18b when the fixing screws 12a and 12b are tightened,
By tightening the fixing screws 12a and 12b, even if a rotational force is applied to the mounting plate 9, the photodetector 7 is held at the position where the adjustment is completed and the mounting plate 9 is fixed.

[0016]

As described above, according to the present invention, the first side of the mounting plate on which the optical block base is mounted is mounted.
A protrusion protruding in the Z-axis direction is provided on the plate surface, an adjusting jig is fitted on the protrusion, and the mounting plate is rotated to adjust the photodetector in the Z-axis direction. Since the first jig surface is pressed against the optical block base by the adjusting jig when the mounting plate is fixed to the optical block base after the adjustment, the mounting is performed by tightening the screw when fixing the mounting plate. The plate can be prevented from rotating, the photodetector can be prevented from being displaced from the position where the adjustment in the X and Y axis directions has been completed, and the mounting plate can be fixed.

[Brief description of drawings]

FIG. 1 is a side view showing an embodiment of the present invention.

FIG. 2 is a front view of FIG.

FIG. 3 is an exploded perspective view of a photodetector mounting device of the optical pickup shown in FIGS. 1 and 2.

[Explanation of symbols]

 1 Optical Block Base 7 Photodetector 8 Printed Circuit Board 9 Mounting Plate 9a First Plate Surface 9b Second Plate Surface 12a, 12b Fixing Screw 13a, 13b Projecting Piece 14a, 14b Dowel 16 Adjusting Screw 18a, 18b Jig

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Mitsuhiko Uchida 2-5-5 Keihan Hondori, Moriguchi City, Osaka Prefecture Sanyo Electric Co., Ltd. (72) Inventor Shozo Iwato, 2-chome Keihan Hondori, Moriguchi City, Osaka No. 5-5 Sanyo Electric Co., Ltd.

Claims (1)

[Claims] 1. A photodetector mounting device for an optical pickup, wherein a photodetector for receiving a light beam modulated on a signal surface of a signal recording medium is mounted on an optical block base provided with various optical elements. It is constructed by bending a metal plate into a substantially U-shaped section by sheet metal working, and a first plate surface, which is one side with the U-shaped bent portion as a boundary, is screwed and attached to the optical block base. And the mounting plate on which the photodetector is mounted on the second plate surface on the other side of the bent portion as a boundary, and the second plate surface is screwed together, and the bent portion is bent depending on the degree of screwing. An adjusting screw that adjusts the ratio to displace the second plate surface in the optical axis direction of the light beam received by the photodetector, and is formed by cutting and raising the first plate surface in the optical axis direction. Together with the mounting plate in the optical axis direction A photodetector mounting device for an optical pickup, comprising: a protruding piece into which an adjusting jig for displacing in a direction orthogonal to each other is fitted.