JPH06124472A - Optical pickup - Google Patents

Abstract

PURPOSE:To restrain that dust particles creep and to prevent that the performance of an optical pickup is dropped by a method wherein, in the optical pickup which is composed of a housing provided with an opening part passing an optical beam and of an object-lens support body, the opening part is closed when the pickup is not operated. CONSTITUTION:A housing opening part 3d in which an optical-part member 14 is built and through which an optical beam is passed is formed in a housing 3. An object lens 1 which condenses the optical beam onto a recording medium is installed in an objectlens support body 2, and the support body 2 is moved to the direction of the optical axis of the optical beam and to a direction perpendicular to the optical axis. The upper face 3c of a housing insertion part 3b in which the opening part 3d radiating the optical beam has been formed is covered with the main-body part 4 of the support body 2 and the opening part 3d is blocked up in a case when an optical pickup is not operated. Thereby, when the optical pickup is not operated, it is restrained that dust particles or the like creep into the housing and it is possible to prevent that the performance of the optical pickup is dropped due to the dust particles.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical pickup for use in an optical information recording / reproducing apparatus such as an optical disc player for recording, reproducing, erasing information on an optical disc which is a recording medium.

[0002]

2. Description of the Related Art Generally, an optical pickup incorporates a light beam generating means such as a semiconductor laser and optical members such as a collimating lens, a beam splitter, and a mirror, and emits a light beam (light beam) or makes a light beam enter. A housing having an opening portion and an objective lens for condensing the light flux emitted from the opening portion of the housing on the recording surface of the optical disc are provided, and the objective lens is orthogonal to the optical axis direction, that is, the focus direction. The objective lens support body is supported so as to be movable in the moving direction, that is, the tracking direction.

A light beam emitted from the opening through each optical member in the housing is collected at a predetermined position on the optical disk into a spot size having a predetermined size by an objective lens adjusted by an objective lens support. Light adjusted. On the other hand, the reflected light from the optical disc passes through the objective lens, enters the housing through the opening, and is sent to the signal detecting means through each optical member in the housing.

Further, in the conventional optical pickup, both during the operation in which the position of the objective lens is adjusted and during the non-operation in which the position of the objective lens is not adjusted, the space between the objective lens support and the housing is set. It has a structure with a gap.

[0005]

However, the fact that there is a gap between the objective lens support and the housing as in the above-mentioned conventional structure means that the internal space of the housing and the external space are in communication with each other. It means that there is. In this way, when the two spaces are in communication with each other, suspended matter such as dust contained in the external space easily enters the inside of the housing through the opening. When dust or the like enters the inside of the housing, it adheres to each of the built-in optical members and stains the optical surface of each optical member. When the optical surface of the optical member becomes dirty, aberration due to light scattering easily occurs, Convergence of the light flux on the disk becomes poor, and unnecessary light loss due to dirt occurs, which hinders recording and reproduction, resulting in deterioration of performance.

Therefore, the present invention has been made in view of the above problems, and suppresses the deterioration of the performance by suppressing the intrusion of dust and the like into the housing, and at the same time, provides an optical pickup which is resistant to heat and vibration from the outside. It is intended to be provided.

[0007]

In order to achieve the above object, an optical pickup according to a first aspect of the present invention is provided with a plurality of optical components inside and a housing having an opening through which a light beam is emitted or incident. And an objective lens support for moving the objective lens in the optical axis direction of the light flux and in a direction orthogonal to the optical axis direction, as well as an objective lens for condensing the light flux emitted from the opening on the recording medium. The optical pickup is characterized in that the opening of the housing is closed by the objective lens support when the optical pickup is not operating.

The optical pickup according to claim 2 is
In order to achieve the above object, in the optical pickup according to claim 1, the objective lens support is arranged at a central position in a direction orthogonal to the optical axis direction.

According to the optical pickup of claim 3,
In order to achieve the above object, in the optical pickup according to claim 1, the objective lens support is fixed in a direction orthogonal to the optical axis direction.

[0010]

According to the structure of the above-mentioned claim 1, since the opening of the housing is closed by the objective lens support when not operating, dust and the like can be prevented from entering the inside of the housing when not operating. To be done.

According to the second aspect of the invention, since the objective lens support member closes the opening of the housing at the center position in the direction orthogonal to the optical axis direction when not operating, It is possible to prevent dust and the like from entering the inside of the housing when it is not operating, and to prevent displacement of the objective lens due to heat or vibration from the outside.

According to the third aspect of the present invention, the objective lens support is fixed so as not to move in the direction orthogonal to the optical axis direction when not operating, and closes the opening of the housing. As a result, dust and the like can be prevented from entering the inside of the housing when not in operation, and
Damage to the objective lens due to external vibration is prevented.

[0013]

【Example】

[Embodiment 1] One embodiment of the present invention will be described with reference to FIGS.
The explanation is based on the following.

As shown in FIG. 1, the optical pickup of this embodiment includes an objective lens 1 and an objective lens support 2 having means for displacing the objective lens 1 and a light beam generating means such as a semiconductor laser. And a housing 3 having a built-in optical member portion 14 including optical members such as a collimator lens, a beam splitter, and a mirror.

As shown in FIG. 2, the objective lens support 2 has a support body 4 to which the objective lens 1 is attached.
And a support base portion 5 serving as a base for the support body portion 4, and a support hinge portion 6 for mounting the support body portion 4 on the support base portion 5 so as to be displaceable in the X and Y directions. The support body 4 includes focus coils 7 and 7 for moving the objective lens 1 in a focus direction which is an optical axis direction of a light beam (light flux) A (see FIG. 3) emitted from the housing 3.
And a radial coil 8 for moving in a tracking direction which is a direction orthogonal to this, and the support base 5 is
A base opening 9 is formed in the center, and a pair of yoke plates 10 and 11 are provided upright on both sides of the base opening 9 to form a yoke.
And a magnet 12 provided on a side surface of each outer yoke plate 11 facing the yoke plate 10. As a result, the objective lens support 2 is moved to the focus coil 7
.7, radial coil 8 ... and a pair of yoke plates 10.1
1 and the magnetic circuit constituted by the magnet 12, the support body 4 is moved in the Y direction, that is, the focus direction,
And the X direction, that is, the tracking direction, to drive the objective lens 1 to be displaced, and the housing 3
The light beam A emitted from is focused and adjusted at a predetermined position on an optical disc, which is a recording medium (not shown), to a spot size of a predetermined size.

On the other hand, a housing 3 having a built-in optical member portion 14 including a light beam generating means for emitting the light beam A and the like.
As shown in FIGS. 1 and 3, is disposed below the support base 5 in the objective lens support 2, and is attached to the lower surface 5a of the support base 5 and the support base 5a. The facing surface 3a facing each other is fixed by the base fixing screws 13. A housing insertion portion 3b to be inserted below the objective lens 1 in the support body portion 4 through a base opening portion 9 provided in the support base portion 5 is formed on the facing surface 3a of the housing 3. The optical member portion 1 built in the housing 3 is provided on the upper surface 3c of the housing insertion portion 3b.
A housing opening (opening) 3d through which the light beam A emitted from the optical disc 4 and reflected light from the optical disk pass is formed. The upper surface 3c of the housing insertion portion 3b is covered with the support body portion 4 and the housing opening portion 3d is closed, as shown in FIG. 1, except during operation. During operation, as in the conventional optical pickup, as shown in FIG. 3, the support body 4 is floated above the support base 5.

As described above, in the optical pickup according to the present embodiment, the upper surface 3c of the housing insertion portion 3b in which the housing opening 3d for emitting the light beam A is formed is provided on the objective lens support 2 except when the optical pickup is in operation. The support body 4 is covered to close the housing opening 3d. Therefore, when not operating, a gap is not formed between the housing opening 3d and the support body 4, so that suspended matter such as dust is prevented from entering the inner space of the housing 3 from the external space, and is not operated. Moreover, intrusion of dust and the like into the housing 3 is suppressed as compared with the conventional optical pickup in which dust and the like easily enter the housing 3. As a result, it is possible to suppress deterioration of performance caused by dust or the like adhering to each optical member of the optical member portion 14 incorporated in the housing 3.

[Embodiment 2] Another embodiment of the present invention will be described below with reference to FIGS. Incidentally, for convenience of explanation, the same reference numerals are given to the means having the same functions as those shown in the above-mentioned embodiment, and the explanation thereof will be omitted.

As shown in FIGS. 4 and 5, the optical pickup of this embodiment has a housing insertion portion 3b of the housing 3.
While the housing taper portion 3e is formed at a predetermined position in the upper part of the lens, the support body portion 4 of the objective lens support 2 is
The objective lens support taper portion 4a is also provided at a predetermined position below the
And the tapered portions 3e and 4a are respectively formed at the center of the housing opening 3d and the body lens 1.
Aligned with the center of the. As a result, when the optical pickup is not in operation, as shown in FIG. 4, the housing insertion portion 3b is fitted to the lower side of the support body 4 to fix the support body 4 in the tracking direction. ing. At this time, the objective lens 1 is located at the center position of the light beam emitted from the housing opening 3d.

As described above, in the optical pickup of this embodiment, the housing insertion portion 3b is fitted to the lower side of the support body 4 to fix the support body 4 in the tracking direction when not operating. Therefore, in addition to the same effects as those of the above-described embodiment, an optical pickup having a structure in which the support hinge 6 is used for the objective lens support 2 and which is easily affected by external vibration or heat is also used. It is possible to have a structure that is strong against external vibration.

Moreover, when the housing insertion portion 3b is fitted on the lower side of the support body portion 4, the objective lens 1 is positioned at the center position of the light beam emitted from the housing opening portion 3d. Therefore, even in an optical pickup that uses the support hinge portion 6 for the objective lens support 2 and is easily displaced due to the influence of external vibration or heat, it is possible to prevent the displacement and to prevent the displacement of the objective lens 1. The alignment can be easily performed.

[0022]

As described above, the optical pickup described in claim 1 has a structure in which the opening of the housing is closed by the objective lens supporter when not operating.

This prevents dust and the like from entering the inside of the housing during non-operation, so that it is easy for dust and the like to enter inside the housing 3 not only during operation but also during operation. Intrusion of dust and the like into the housing 3 is suppressed as compared with the conventional optical pickup. As a result, there is an effect that it is possible to suppress the performance deterioration caused by dust or the like adhering to each optical member of the optical member portion 14 incorporated in the housing 3.

The optical pickup according to claim 2 is
As described above, in the optical pickup according to claim 1, the objective lens support is arranged at the center position in the direction orthogonal to the optical axis direction.

As a result, the same effects as those of the above-described claim 1 are achieved, and the effect of preventing the displacement of the objective lens due to heat or vibration from the outside is exhibited.

According to the optical pickup of claim 3,
As described above, in the optical pickup according to the first aspect, the objective lens support is fixed in the direction orthogonal to the optical axis direction.

As a result, the same effects as those of the above-mentioned claim 1 are achieved, and also the effect of preventing damage to the objective lens due to external vibration is exhibited.

[Brief description of drawings]

FIG. 1 is a schematic view of an optical pickup according to an exemplary embodiment of the present invention viewed from a body lens side when not operating.

FIG. 2 is an exploded perspective view of an objective lens supporter that constitutes the optical pickup.

FIG. 3 is a schematic view of the optical pickup as viewed from a body lens side during operation.

FIG. 4 is a schematic view of an optical pickup according to another embodiment of the present invention as viewed from the object lens side when not operating.

5 is a schematic view of the optical pickup shown in FIG. 4 viewed from the objective lens side during operation.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Objective lens 2 Objective lens support body 3 Housing 3b Housing insertion part 3d Housing opening (opening) 3e Housing taper part 4 Support body part 4a Objective lens support taper part 5 Support base part 6 Support hinge part 14 Optical member (optical member) A Light beam

Claims (3)

[Claims] 1. A plurality of optical components are provided inside, a housing having an opening through which a light beam is emitted or incident, and an objective lens for condensing a light beam emitted from the opening onto a recording medium are provided. In an optical pickup having an objective lens supporting body that moves the objective lens in the optical axis direction of the light flux and in a direction orthogonal to the optical axis direction, the opening of the housing is closed by the objective lens supporting body when not operating. An optical pickup characterized by being peeled off. 2. A plurality of optical components are provided inside, a housing having an opening through which a light beam is emitted or incident, and an objective lens for condensing a light beam emitted from the opening onto a recording medium are provided. In an optical pickup having an objective lens supporting body that moves the objective lens in the optical axis direction of the light flux and in a direction orthogonal to the optical axis direction, the opening of the housing is closed by the objective lens supporting body when not operating. An optical pickup characterized in that the objective lens support is provided at a central position in a direction orthogonal to the optical axis direction while being separated. 3. A housing having a plurality of optical members therein, having a housing in which an opening for emitting or entering a light beam is formed, and an objective lens for condensing the light beam emitted from the opening onto a recording medium. In an optical pickup having an objective lens supporting body that moves the objective lens in the optical axis direction of the light flux and in a direction orthogonal to the optical axis direction, the opening of the housing is closed by the objective lens supporting body when not operating. An optical pickup characterized in that the objective lens support is fixed and is fixed in a direction orthogonal to the optical axis direction.