JPH03224143A - Optical pickup device - Google Patents

Abstract

PURPOSE:To maintain a stable condition of holding the position of a photodetector against external force by forming a side wall of an adjusting plate into a shape approximately along the side of the photodetector, interposing an adhesive part between this side wall and the side of the photodetector and fixing them accordingly. CONSTITUTION:This device is provided with the adjusting plate 18 and a transparent hole provided on this adjusting plate to be irradiated with reflected light L from a disk 9, and the side wall 20 of the adjusting plate is formed approximately along the side 16 of the photodetector 2 by a press, etc. In this case, since the photodetector 2 is firmly fixed via the adhesive part 21 to the adjusting plate 18, the photodetector 2 is not varied relatively in position with the adjusting plate 18 against external force. By this method, the stability of the position of the photodetector is drastically improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Applications] The present invention relates to an optical pickup device, and particularly to a fixing structure for a photodetector.

[Conventional technology]

An example of the prior art will be explained based on FIGS. 2 to 4.

FIG. 2 is a plan view of a photodetector mounting part in a conventional optical pickup device, and in the figure, 1 is an optical unit;
2 is a photodetector, 3 is an adjustment plate, and 4 is a flexible printed circuit board (abbreviated as FP width) on which a conductive portion 5 is formed, which is adhered with an adhesive portion 13 to be described later.

Reference numeral 6 indicates a lead portion for outputting the electrical output from the photodetector 82 to a reproducing device (not shown), and 7 indicates a terminal of the photodetector 2, which consists of eight terminals. Reference numeral 8 denotes a known adhesive portion for fixing the adjustment plate 3 to a predetermined position on the optical unit 1, whereby the photodetector l#2 is positioned and fixed on the micron order by a known adjustment cover.

FIG. 3(a) is a schematic explanatory diagram showing an astigmatism optical system using a half mirror as an example of a conventional example, and FIG. 3(b) is a diagram showing the position 0. ．． The shape of a light spot on light detection l#2 in 0 roe is shown.

In the figure, 9 is a disk, 10 is an objective lens formed in a known actuator, and 11 is a half mirror 112 installed inside the optical unit 1, which is a magnifying lens.

The spot shape on the four-divided light detection 412 is at position S
It becomes circular at the in-focus position. Using that property, patterns A, B, and C are each divided.

Light detection N2 to a position S where the light outputs on D are equal.
are adjusted in the X and Y directions, and the magnifying lens 12 is adjusted in the D direction using a known adjuster on the order of 1 micron.

Fig. 4 is a side sectional view of Fig. 2. In Fig. 4, numerals 1 to 4 and 6 to 8 are the same as in Fig. 2, and 13 is a thermosetting material with excellent heat resistance and adhesive strength. an adhesive part, 15 a solder part for electrically and mechanically connecting and fixing the photodetector 2 to F2O3;
16 is a side surface of the photodetector 2, and 17 is a side wall of the adjustment plate 3.

[Problem to be solved by the invention]

As described above, in the conventional configuration, since the photodetector 2 is fixed in the air via F2O3, the external force
, F, and G are added, the photodetector I and the optical sensor 2 change their dimensions a, b, and 'Q, respectively, which causes a deviation from the focus position S, which impairs the performance of the optical pickup device. made worse. Furthermore, in order to prevent movement, the adhesive 13 for fixing F2O3 needs to be highly reliable, which inevitably increases the cost. The present invention has been made to solve this problem, and provides an optical pickup device having a structure for fixing a photodetector that does not change due to external force.

[Means to solve the problem]

In the optical pickup device according to the present invention, a through hole having a side wall portion formed in a shape that substantially follows the side surface of the photodetector is formed in the adjustment plate for fixing the photodetector, and the through hole has a side wall portion formed in a shape that substantially follows the side surface of the photodetector. An adhesive part is interposed between the adjustment plate and the through-hole side wall part to fix the adjustment plate.

[Effect]

In the present invention, since the adjustment plate and the photodetector are fixed with adhesive, the photodetector and the 'H adjustment plate will not be relatively shifted due to external force. This greatly improves the positional stability of the device.

〔Example〕

An embodiment of the present invention will be described below with reference to FIG.

FIG. 1 is a side sectional view showing the main parts of the present invention, and in the figure, reference numerals 1, 2, 4 to 16 have the same structure as the conventional example.

18 is an adjustment plate, and 19 is a disk 9 provided on this adjustment plate.
A through hole through which reflected light is incident, 20 is its side wall,
It is formed into a shape substantially along the side surface 1B of the photodetector 2 by pressing or the like. Reference numeral 21 denotes an adhesive portion filled between the side surface 16 and the side wall 20, and is made of, for example, a known UV adhesive.

Reference numeral 22 denotes an adhesive for adhering F2O3 to the adjustment plate 18, and in this example, it is a pressurized type and low cost.

In the above configuration, since the photodetector 2 is firmly fixed to the adjustment plate 18 via the adhesive part 21, the photodetector 2 does not move relative to the adjustment plate 18 due to external force. It is something.

Furthermore, in this example, the adhesive 22 for adhesively fixing F2O3 to the control side 18 is of a low-cost pressurized type, which also allows sufficient fixation of the photodetector Wj2.

〔Effect of the invention〕

As explained above, according to the present invention, a side wall is formed on the adjustment plate in a shape that roughly follows the side surface of the photodetector, and the adhesive part is interposed between the adjustment plate and the side wall to fix the photodetector. When holding position, it can maintain an extremely stable state against external forces,
Therefore, high reliability can be maintained over a long period of time.

[Brief explanation of drawings]

Fig. 1 is a side cross-sectional view of main parts showing one embodiment of the present invention;
FIG. 3 is a schematic optical path diagram of an optical system using a half mirror, and FIG. 4 is a side sectional view of FIG. 2. In the figure, 1 is an optical unit, 2 is a photodetector, 16 is a side surface,
18 is an adjustment plate, 20 is a side wall, and 21 is an adhesive portion. Saij Izuo Izuko (α)

Claims (1)

[Claims] A photodetector that receives reflected light from a disk on which a signal has been formed and outputs an electrical signal in accordance with the signal, and a through hole having a side wall portion shaped approximately along the side surface of the photodetector. , an adjustment plate that can adjust the reflected light in a plane perpendicular to at least the optical axis direction; and an adhesive part interposed and fixed between the side surface of the photodetector and the through-hole side wall of the adjustment plate; An optical pickup device comprising: