JPH0447769Y2 - - Google Patents

Description

[Detailed Description of the Invention] Field of Industrial Application This invention relates to an optical system support device for an optical pickup used in compact disc players, video disc players, and the like.

〓Summary of the invention〓 A collimator lens whose front surface is positioned by a flange protruding from the inner wall of the optical path hole, a biasing means provided between the rear surface of the collimator lens and the prism, and a prism fixed to the front surface. This is an optical system support device for an optical pick-up that is composed of a prism base that is rotatably supported around the optical axis and a sealing member that positions the rear surface of the prism base. Can be assembled without gluing to
Further, there is no need to provide a wave washer between the prism base and the sealing member.

〓Prior Art〓 Fig. 3 shows a longitudinal sectional view of a conventionally known device of this type, and its structure will be briefly explained.

Two flanges 1a and 1b are protruded from the inner wall of the optical path hole formed in the body 1 of the optical pickup, and the rear surface of the collimator lens 2 is connected to one of the flanges 1a.
It is positioned in contact with the body 1, and its periphery is fixed to the body 1 using an adhesive 2a.

In addition, the prism base 4 to which the prism 3 is fixed is
is positioned by abutting the other flange 1b, and is pressed forward by an annular wave washer 5 provided between the prism base 4 and the sealing member 7, whereby the prism base 4 is centered on the optical axis. It is rotatably supported.

However, because of this configuration, it is necessary to glue the collimator lens 2 to the body 1 of the optical pickup during assembly, which not only makes assembly work easier, but also causes the collimator lens to be glued to the body 1 of the optical pickup during assembly. There was a risk that the position of No. 2 would shift.

Another drawback is that it is difficult to control the elasticity of the wave washer 5, causing product variations.

〓Problems to be solved by the invention〓 The purpose of this invention is to improve the above-mentioned drawbacks of the conventional device.It is a wave washer that does not require gluing the collimator lens to the body, improves assembly workability, and is difficult to control elasticity. An object of the present invention is to provide an optical system support device for an optical pickup that does not use an optical system.

〓Means for solving the problem〓 In order to achieve the above object, the optical system support device of the optical pickup of this invention uses a collimator lens whose front surface is positioned by a flange protruding from the inner wall of the optical path hole. , a biasing means provided between the rear surface of the collimator lens and the prism, a prism base with the prism fixed to the front surface and rotatably supported around the optical axis, and a seal for positioning the rear surface of the prism base. and a stop member.

〓Effect〓 By doing this, when assembling,
It is easy to work by simply inserting the collimator lens, the biasing means, and the prism base to which the prism is bonded in advance into the optical path hole of the body of the optical pickup in this order, and finally fitting and fixing the sealing member.

〓Example〓 An example of this invention will be described with reference to FIG.

An optical path hole is formed through the aluminum die-cast body 1 of the optical pickup, and the front surface of the collimator lens 2 is positioned by coming into contact with a flange portion 1a protruding from the front end of the inner wall of this optical path hole. There is.

A prism 3 is placed in advance behind the collimator lens 2.
A prism base 4 to which is fixed with adhesive is supported rotatably around the optical axis, a compressed coil spring 6 is provided between the collimator lens 2 and the prism 3, and the rear surface of the prism base 4 is sealed. It is positioned in contact with member 7.

A laser diode 8 is provided in the sealing member 7, and the laser light emitted from the laser diode 8 is transmitted to the center hole of the prism base 4, the prism 3, the collimator lens 2, and an objective lens (not shown) disposed in front of the laser diode 8. ) is used to illuminate compact discs, video discs, etc.

The prism 3 is made by laminating two right-angled prisms with surfaces inclined at 45 degrees to the optical axis with a semi-transparent mirror 3a in between. The prism base 4 is rotated around the optical axis to ensure that the reflected light is properly centered on the photo detector. Make fine adjustments so that it is incident.

Figure 2 shows the assembly method (the top and bottom are reversed from Figure 1), in which the collimator lens 2, coil spring 6, and prism 3 are glued in advance from behind the optical path hole of the body 1. The prism base 4 is inserted in this order, and finally the sealing member 7 is fitted and fixed by known means such as press-fitting, adhesion, screwing, etc.

<Effects of the invention> As explained above, the optical system support device of the optical pick-up of this invention has a collimator lens whose front surface is positioned by a flange protruding from the inner wall of the optical path hole, and a rear surface of the collimator lens. Consisting of a biasing means provided between the prism, a prism base that fixes the prism on the front surface and is rotatably supported around the optical axis, and a sealing member that positions the rear surface of the prism base. As a result, there is no need to glue the collimator lens to the body, making assembly work extremely easy.If the collimator lens is defective, it can be easily replaced.Since it does not use a wave washer, which is difficult to control the spring constant, there is less variation in the product. There is no need for a reference surface (flange) for positioning the prism base, reducing the need for precision machining on the body.
This has a unique effect.

[Brief explanation of the drawing]

Figure 1: longitudinal sectional view of an embodiment of this invention, Figure 2
Figure... its assembly diagram, Figure 3... longitudinal sectional view of the conventional device, 1... body, 1a, 1b... flange, 2... collimator lens, 2a... adhesive, 3... prism, 3a ...Semi-transparent mirror, 4...Prism base, 5
... Wave washer, 6 ... Coil spring, 7 ... Sealing member, 8 ... Laser diode.

Claims (1)

[Scope of Claim for Utility Model Registration] (a) A collimator lens whose front surface is positioned by a flange protruding from the inner wall of the optical path hole, and (b) An urging force provided between the rear surface of the collimator lens and the prism. (c) a prism base having a prism fixed to its front surface and supported rotatably around an optical axis; and (d) a sealing member for positioning the rear surface of the prism base. Support device.