JPH1064106A - Dustproof mechanism for optical pickup - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent dust, etc., from sticking to a beam splitter arranged on the side of a base in a simple constitution. SOLUTION: A skirt 10 being the dustproof means is for the purpose of shutting down an intruding passage of dust 88 into a hole 80, and is formed integrally with a movable body 64 along the vertical direction to oppose a gap 86 between the movable body 64 and the base 60. That is, the skirt 10 is formed to be annular extending along the outer side of a circumferential wall 82 to position its lower end lower than the base 60. Then, the upper end of the circumferential wall 82 is made higher than the base 60, and also the height of the circumferential wall 82 is made to overlap the movable body 64. Dust 88 intruding into the gap 86 comes into collision with the skirt 10 or the circumferential wall 82 to drop into a recessed part 83. Consequently, since dust 88 is prevented from intruding into the hole 80 by the skirt 10 and the circumferential wall 82, the dust 88 is not stuck on the beam splitter, thus preventing a read failure.

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 reading information recorded on an optical disk recording medium, and more particularly, to a dustproof mechanism for preventing dust and the like from entering an irradiation light receiving path of the optical pickup. .

[0002]

2. Description of the Related Art FIGS. 7 and 8 show a pickup 56. FIG. 7 is an overall perspective view of the pickup 56, and FIG. 8 is an exploded perspective view of the pickup 56. In the following drawings, arrow F indicates a forward direction, arrow B indicates a backward direction, and arrow R
Is rightward, arrow L is leftward, arrow UP is upward, arrow D
N indicates a downward direction.

A movable body 64 having an objective lens 62 is disposed on a base 60 of the pickup 56, and a support 66 is connected to the movable body 64. This support 6
6 is a pair of fixing pins 62 projecting from the base 60.
(See FIG. 8), and the movable body 64 is connected to the base 60.

On the left and right sides of the movable body 64, square tubular focus coils 68, 70 are disposed, and outside the focus coils 68, 70, tracking coils 72, 74 are provided.
(Only the left side is shown in FIG. 8).

[0005] As shown in FIG. 8, a base 60 has focus coils 68 and 70 and tracking coils 72 and 70.
The substantially U-shaped permanent magnets 76 and 78 facing the base 74 are arranged.

Then, the permanent magnets 76 and 78 and the coil 6
The movable body 64 is formed by the base 60
Move up and down and left and right. That is, the movable body 64
It is configured to be movable so that focus servo or tracking servo can be performed. Therefore, as shown in FIG. 9, a gap 86 is provided between the movable body 64 and the base 60 in the pickup 56.

The objective lens 62 is fixed to the front end of the movable body 64, and a hole 80 (see FIG. 9) serving as an irradiation light receiving path is formed in a portion of the base 60 corresponding to the objective lens 62.

A peripheral wall 82 projects upward from the periphery of the hole 80, and a recess 8 is formed outside the peripheral wall 82.
3 are formed. Here, the peripheral wall 82 is provided so as to prevent external light from reaching a beam splitter 84 described later.

As shown in FIG. 9, a beam splitter 84 is disposed below the hole 80. A laser diode (not shown) is arranged below the beam splitter 84, and a photodetector (not shown) is arranged on the left side of the beam splitter 84.

The light that has exited the laser diode passes through a beam splitter 84, passes through an objective lens 62, and is supplied to a disc (not shown). The reflected light from the disc passes through the beam splitter 84 and passes to a photodetector. Supplied.

As is well known, the irradiation and light receiving means disposed on the side of the base 60 comprises a laser diode, a beam splitter 84, a photodetector and the like.

[0012]

As described above, since the movable body 64 is movably disposed, the movable body 64 is not provided.
A gap 86 is provided between the base and the base 60. Therefore, the floating dust 88 enters the hole 80 from the gap 86 and adheres on the beam splitter 84.

Here, the peripheral wall 82 is raised and dust 88 is formed in the hole 8.
Although it is conceivable to prevent the dust from entering the inside, the height of the peripheral wall 82 is limited because the movable body 64 can be moved up and down. And the dust 88 adheres to the beam splitter 84.

If dust 88 adheres to the beam splitter 84, the dust 88 reduces the amount of light from the beam splitter 84 and the amount of light reflected from the disk, causing a reading error of the photodetector.

It is an object of the present invention to prevent dust and the like from adhering to the irradiation and light receiving means arranged on the base side with a simple configuration.

[0016]

According to a first aspect of the present invention, there is provided a dustproof mechanism for an optical pickup, comprising: a base provided with a hole forming an irradiation light receiving path and irradiation light receiving means; an objective lens; In an optical pickup including a movable body movably disposed, dust prevention means for preventing dust or the like from entering the hole through a gap between the movable body and the base is provided.

In the dustproof mechanism of the optical pickup according to the first aspect of the present invention, dust or the like entering from the gap collides with the dustproof means and is repelled. Therefore, dust and the like are prevented from entering the hole by the dust-proof means, so that, for example, the amount of light to the photodetector does not decrease, and reading errors are prevented.

In a dustproof mechanism for an optical pickup according to a second aspect of the present invention, the dustproof means is formed on the movable body along a peripheral wall protruding from the periphery of the hole, and the peripheral wall is provided with the dustproof means. It is characterized in that the length is overlapped with the length.

In the dust-proof mechanism of the optical pickup according to the second aspect of the present invention, the dust-proof means and the peripheral wall prevent dust from entering the hole.

In a dustproof mechanism for an optical pickup according to a third aspect of the present invention, the movable body and the base are provided with a pair of the dustproof means along a peripheral wall projecting from the periphery of the hole.
It is characterized in that these dustproof means are overlapped.

According to the dustproof mechanism of the optical pickup according to the third aspect of the present invention, the intrusion of dust into the hole is further prevented by the pair of dustproof means and the peripheral wall.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION

(First Embodiment) FIGS. 1 to 3 show a dustproof mechanism of an optical pickup 56 according to a first embodiment of the present invention. FIG. 1 is a perspective view of the optical pickup 56, and FIG. 2 is a partial sectional view thereof. In these figures, parts corresponding to those in FIGS. 7 and 9 are denoted by the same reference numerals, and detailed description thereof will be omitted.

As shown in FIG. 2, the movable body 64 is provided with a dust intrusion prevention skirt (hereinafter simply referred to as a “skirt”) 10 as dustproof means.
6, and are integrally formed along the up-down direction. That is, the skirt 10 is provided with dust 88 against the hole 80.
Is formed in a ring shape along the outside of the peripheral wall 82, and is formed so that the lower end is located below the base 60.

The upper end of the peripheral wall 82 is higher than the base 60, and the peripheral wall 82 has a height overlapping the movable body 64. The positions of the skirt 10 and the peripheral wall 82 are outside the vertical and horizontal movable ranges of the movable body 64 so as not to hinder the movement of the movable body 64 (see FIG. 3).
FIG. 3 shows a state in which the movable body 64 has moved down and moved to the left.

In the present embodiment, dust 88 entering from the gap 86 collides with the skirt 10 or the peripheral wall 82 and falls into the recess 83. Therefore, according to the present embodiment, since the dust 88 is prevented from entering the hole 80 by the skirt 10 and the peripheral wall 82, the amount of light to the photodetector does not decrease, and reading errors are prevented. (Second Embodiment) FIGS. 4 to 6 show a dustproof mechanism of an optical pickup 56 according to a second embodiment of the present invention. FIG. 4 is a perspective view of the optical pickup 56, and FIG. 5 is a partial sectional view thereof. In these figures, parts corresponding to those in FIGS. 7 and 9 are denoted by the same reference numerals, and detailed description thereof will be omitted. FIG. 6 shows a state where the movable body 64 has moved down and moved to the right.

In the second embodiment, as shown in FIG. 5, the projections 12, 14 as dustproof means are formed so as to overlap the base 60 and the movable body 64. These protrusions 12 and 14 are formed in an annular shape outside the peripheral wall 82 and along the peripheral wall 82. The protrusion 14 is located between the peripheral wall 82 and the protrusion 12.

According to this embodiment, the pair of dustproof means 1
The intrusion of dust 88 into the hole 80 is further prevented by the peripheral walls 82 and 14. Other configurations and effects are the first.
This is the same as the embodiment.

The irradiation and light receiving means provided on the base 60 side includes a half mirror, a collimator lens, a laser diode and the like in addition to the beam splitter, and the dustproof means of the present invention prevents dust from adhering to these. To prevent.

[0029]

As described above, according to the present invention, a simple structure is provided in which dust is prevented from entering a hole of dust or the like from a gap between a movable body and a base. Adhesion of dust and the like to the light receiving means is prevented.

[Brief description of the drawings]

FIG. 1 is a perspective view of an optical pickup according to a first embodiment of the present invention.

FIG. 2 is a partial cross-sectional view of the optical pickup according to the first embodiment.

FIG. 3 is a partial cross-sectional view showing a state where the movable body of FIG. 2 has moved.

FIG. 4 is a perspective view of an optical pickup according to a second embodiment of the present invention.

FIG. 5 is a partial cross-sectional view of an optical pickup according to a second embodiment.

FIG. 6 is a partial sectional view showing a state where the movable body of FIG. 5 has moved.

FIG. 7 is a perspective view of an optical pickup according to a conventional example.

FIG. 8 is an exploded perspective view of an optical pickup according to a conventional example.

FIG. 9 is a partial sectional view of an optical pickup according to a conventional example.

[Explanation of symbols]

 Reference Signs List 10 dust intrusion prevention skirt (dustproof means) 12, 14 protrusion (dustproof means) 56 optical pickup 60 base 62 objective lens 64 movable body 80 hole 82 peripheral wall 84 beam splitter 86 gap 88 dust

Claims (3)

[Claims] 1. An optical pickup comprising: a base provided with a hole forming an irradiation light receiving path and irradiation light receiving means; and a movable body provided with an objective lens and movably arranged with respect to the base. A dustproof mechanism for an optical pickup, further comprising dustproof means for preventing dust and the like from entering the hole from a gap with the base. 2. The dustproof means is formed on the movable body along a peripheral wall protruding from the periphery of the hole, and the peripheral wall has a length overlapping with the dustproof means. Item 3. A dustproof mechanism for an optical pickup according to Item 1. 3. A pair of said dustproof means is provided on said movable body and said base along a peripheral wall protruding from the periphery of said hole,
2. A dustproof mechanism for an optical pickup according to claim 1, wherein said dustproof means are overlapped.