JP2536842Y2 - Optical recording / reproducing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an optical recording / reproducing apparatus provided with a vent for preventing dust from adhering to an optical member in a pickup.

[Related Art] In recent years, information is recorded by condensing a light beam and irradiating the recording medium, and the recorded information is reproduced by receiving return light of the light beam irradiated on the recording medium. An optical (information) recording / reproducing apparatus capable of reading or writing has been put to practical use.

The above-described device has an advantage that it can record a large amount of information because it can record at a higher density than a device using a conventional magnetic head.

FIG. 9 shows a conventional optical pickup 81 used for the recording / reproducing apparatus.

As shown in FIGS. 9 (a) and 9 (b), the light from the laser light source 82 is collimated by a collimator lens 83 and is incident on a polarization beam splitter 84. This polarization beam splitter
Reference numeral 84 indicates that the P-polarized light component is transmitted by 50% and the S-polarized light component is reflected by 100%. Next, the light is reflected by the total reflection mirror 85 in the direction of the objective lens 86, and is condensed on the disk through the objective lens 86. The light reflected on the disc passes through the objective lens 86, is reflected by the total reflection mirror 85 in the direction of the laser light source 82, reflects the return light having a Kerr rotation component on the disc by the polarizing beam splitter 84, and The light whose direction has been changed by the other half prism 87 reaches the light receiving element 89 through the critical angle prism 88. Further, the light that has traveled straight without changing the direction by the half prism 87 passes through a half-wave plate 90, is split into two lights by a polarizing beam splitter 91, and reaches the light receiving elements 92 and 93, respectively.

The objective lens 86 provided in the actuator 94 is opposed to the disk surface so as to be driven by a spring material or the like. The disk is electromagnetically driven so that it can follow the surface deflection and eccentric direction of the disk.

This optical pickup 81 has a problem that dust passes through the inside of the actuator 94 and enters the inside of the pickup body 95 from the gap around the objective lens 86 of the actuator 94 as shown by an arrow. If the dust enters, the dust adheres to various optical components and adversely affects optical performance such as reflectance and transmittance.

In particular, dust entering along the path indicated by the arrow easily adheres to the surface of the total reflection mirror 85. And if dust adheres to this, the change of the phase difference will increase. In an optical pickup for a magneto-optical disk, when a phase difference occurs, a magneto-optical reproduction signal is deteriorated. It is said that the amplitude of the reproduced signal attenuates in proportion to cos δ with respect to the phase difference δ, δ = 90 °
In this case, a reproduced signal cannot be obtained.

In addition, a derivative multilayer film is deposited on the surface of the total reflection mirror 85 to increase the reflectance. However, if dust adheres, the effect of the derivative multilayer film is reduced, the reflectance is reduced, and the phase difference is reduced. Will change.

This problem is temporarily solved by the proposal of Japanese Patent Application Laid-Open No. 61-236040. According to FIG. 3 of this publication, the configuration is such that dust is prevented from entering by closing the housing 7 with the 1 / 4λ plate 6.

[Problems to be Solved by the Invention] However, this method can be used only when the 1 / 4λ plate is included in the optical system, and is not versatile. Instead of using a λ / 4 plate, a flat glass plate may be used, but this is not an excellent method because it increases the number of components and changes the amount of birefringence.

The present invention has been made in view of the above points, and can easily prevent dust from entering through an opening around an objective lens and adhering to an optical member or the like in an optical pickup and adversely affecting the optical system. It is an object of the present invention to provide an optical recording / reproducing apparatus which can be widely applied without depending on the configuration of the optical recording / reproducing apparatus.

[Means and Actions for Solving the Problems] An optical recording / reproducing apparatus according to the present invention comprises: an objective lens which moves in a radial direction of a recording medium to focus and irradiate the recording medium; A movable member comprising: an objective lens driving unit that controls an irradiation position; and at least a part of an optical member that connects an optical path between the objective lens, a light beam generation element, and a light detection element. A cover member that covers and has an opening formed in a portion facing the objective lens, wherein another opening different from the opening is formed in the movable member or the cover member, and the opening and the other opening are formed. And an optical recording / reproducing apparatus having an optical pickup that communicates with at least one of the inside of the movable member and the inside of the cover member. It is formed only in the direction of the air flow due to the rotation of the recording medium above, or only in the direction of the air flow that combines the air flow due to the rotation of the recording medium on the objective lens and the air flow due to the fan. Even if dust enters the movable member or the cover member, an air flow is formed between the opening and another opening different from the opening, The dust is discharged to the outside by this air flow.

Hereinafter, the present invention will be described in detail with reference to the drawings.

1 to 4 relate to a first embodiment of the present invention, FIG. 1 is a side view showing a schematic configuration of an optical disk device of the first embodiment, FIG. 2 is a perspective view showing a front panel, FIG. FIG. 3 is a plan view of the optical pick as viewed from above, and FIG. 4 shows an actuator.

As shown in FIG. 1, an optical disc apparatus 1 according to the first embodiment has a deck section 5 provided with an optical pickup 3, a spindle motor 4 and the like housed in, for example, a box-shaped apparatus housing 2. The deck member 5 is fixed to a base 8 surface of the device housing 2 via an insulator 6 and a deck mounting member 7.

The pickup 3 is, for example, an optical system similar to the conventional example shown in FIG. That is, a light emitting element by a semiconductor laser or the like, a light detecting element for converting a reflected light beam from the disk 9 into an electric signal, and an optical element for condensing and irradiating the disk from the light emitting element and guiding return light from the disk 9 to the light detecting element. It has members and the like. FIG. 4 shows the actuator 10 part.

The deck section 5 has mounted thereon a spindle motor 4 for rotating the disk 9, a voice coil motor (VCM) for moving the optical pickup 3 in the radial direction of the disk 9, and a pickup moving mechanism such as a gear and a screw mechanism. It is a unit, and only this deck part 5 can be exchanged independently.

The insulator 6 is provided between the mounting member 7 and a rubber material, a plastic material, or a combination thereof in order to minimize transmission of external vibration to the deck portion 5. .

As shown in FIG. 2, an insertion port 12 for a cartridge case 11 is provided on the upper front side of the front panel serving as the front panel of the apparatus housing 2. The inserted cartridge case 11 can be inserted or ejected.

The opening / closing lid 13 is closed except during insertion and ejection, so that dust does not enter the apparatus 1.

When the cartridge case 11 is inserted from the insertion opening 12, the cartridge case 11 is transported by a loading mechanism (not shown), and the disk 9 is placed on the turntable 4A on the axis of the spindle motor 4.

The disk 9 placed on the turntable 4A is
By operating an eject button 14 provided on the front surface, the cartridge is transported to the insertion slot 12 by an eject mechanism for transporting the cartridge case 11 in a direction opposite to the loading direction.
From the insertion slot 12.

A ventilation port 15 is provided below the insertion port 12. The ventilation holes 15 allow ventilation in the optical disk device 1 and have a structure in which a large number of through holes are provided, for example, in a lattice shape.

A dustproof filter 16 is detachably mounted inside the ventilation hole 15, that is, on the back surface of the front panel.
The filter 16 prevents dust from entering along with the air flowing from the ventilation port 15.

An exhaust port 17 is provided on the back surface of the device housing 2, and a filter 18 and a fan 19 are provided inside the opening.

The fan 19 is for letting out the air in the apparatus 1 to the outside. When the fan 19 is operating, dust can be prevented from flowing in from the exhaust port 17. When not operating, the filter 18 prevents dust from flowing in from the outside together with air.

Incidentally, the actuator 10 constituting the optical pickup 3 has a structure as shown in FIG.

The objective lens 21 is attached to an iron piece 22. The iron piece 22 is attached to the tip of two leaf springs 24 erected on a bobbin 23. The objective lens 21 is held movably in the radial direction Ra of the disk 9. I have.

A magnetic circuit composed of magnets 25, 25 and yokes 27, 27 around which tracking coils 26, 26 are wound is provided around the iron piece 22, and the magnetic circuit is composed of an actuator frame.
Fixed to 30. Therefore, the tracking coils 26,2
By supplying a drive signal to 6, the objective lens 21 can be moved in the radial direction Ra of the disk 9.

The bobbin 23 is supported by the frame 30 and two spiral leaf springs 31 and 31 ', and is movable with respect to the frame 30 in the optical axis direction of the objective lens 21, that is, in the focus direction Fo. .

A focusing coil 32 is wound around a cylindrical coil frame attached to the bobbin 23. A yoke 34 for passing the magnetic flux of the magnet 33 extends in the cylindrical direction of the coil 32, and the extended end faces the yoke 35. Therefore, by supplying a drive current to the coil 32, the bobbin 23
, That is, the objective lens 21 can be moved in the focus direction Fo.

Thus, the two-dimensional actuator 10 that can move the objective lens 21 in the radial direction Ra and the focus direction Fo is formed.

Although the structure of the objective lens 21 on the side of the optical pickup 3 on the lower side in the optical axis direction is omitted, for example, it is the same as that shown in FIG.

On the upper side of the frame 30, a cap 36 having an opening at a portion facing the objective lens 21 is provided as shown in FIG. 4 (c). An opening 37 serving as a vent is provided on a side surface of the cap 36.

The position where the opening 37 is provided is provided in a portion E opposite to the spindle motor 4 as shown in FIG.

The position of the opening 37 assumes a case where an air flow is formed in the direction of arrow A by the fan 19 in FIG. 1 and the disk 9 is rotated in the direction C in FIG.

That is, at the position where the objective lens 21 facing the disk 9 faces, the air flow has a component in the direction of arrow A, and
The rotation of the disk 9 also has a component in the tangential direction T, so that the combined airflow is expected to be in the direction of arrow P1.

The opening 37 provided in the portion E opposing in the direction of the arrow P1 allows dust to enter through the opening 37 to the outside by airflow even if dust enters from above the objective lens 21 through the surrounding gap. .

In FIG. 3, the dotted line indicates the opening 38 of the cartridge case.
By moving the optical pickup 3 in the longitudinal direction of the opening 38, an arbitrary track can be accessed and information can be recorded or reproduced.

According to the first embodiment, by the operation of the fan 19, the air flowing from the vent 15 on the front panel side is exhausted to the outside from the exhaust port 17 on the back side. In the optical pickup 3, from above the objective lens 21, the objective lens 21
The air flowing into the space around the opening 36 is rotated by the rotation of the fan 19 and the disk 9 so that the opening 37 formed on the side surface of the cap 36 is opened.
An airflow exiting from is formed. Therefore, even if dust flows in with the air, the dust can be flown out of the opening 37 by this air flow, and it is possible to effectively prevent dust from entering the optical member side such as a lower mirror. It is possible to effectively prevent dust from adhering to the device and causing adverse effects.

Further, this dustproof means can be realized by merely providing an opening 37 for ventilation in the cap 36, and can be applied to any structure regardless of the configuration of the optical pickup, for example, whether or not it is a magneto-optical system.

In the first embodiment, as shown in FIG. 3, the case where the disk 9 rotates in the direction C and the fan 19 draws and exhausts air in the direction of arrow A (abbreviated simply as "drawing") has been described.

Therefore, if the direction of retraction by the fan 19 is different from the direction A or the rotation direction of the disk 9 is opposite,
The optimum position for providing 37 is naturally different.

For example, when the fan 19 is pulled in the direction A by the fan 19 as in the first embodiment, the rotation direction of the disk 9 is D
In the case where the optical pickup is rotated in the direction shown in FIG.
The part indicated by D) is desirable.

When the direction of retraction by the fan 19 is reversed, that is, when the retraction is performed in the direction B in FIG.
If the direction of rotation of C is in the C direction, the position of the opening is S (B, C)
Is desirable, and in the case of the D direction, S (B, D) is desirable.

Next, a case where a lens actuator different from the lens actuator of the first embodiment is used will be described below.

A lens actuator 41 shown in FIG. 6 has a wire 42 with a rubber damper instead of the leaf springs 24, 24, 31, 31 'of the first embodiment.
42, 42 ', 42' are used. Further, a magnetic circuit that also serves as a focus and tracking drive unit is used, a focus and tracking coil is wound around a yoke material of the fixed magnetic circuit, and a magnetic body is fixed to the movable part of the objective lens 21.

Also in this actuator 41, the actuator outer frame
As shown in FIG. 6 (c), a ventilation port 44 is provided on the side surface of the
Means for preventing intrusion into the iso-optical pickup side is formed.

In the actuator 51 shown in FIG. 7, the objective lens 21 slides on the rotation axis, performs tracking control, and a drive coil for performing focus control in the movable member is located in a gap of a focus drive magnetic circuit. 4 has a structure in which a leaf spring acts as a restoring force, as in FIG.

The lens holder 52 of the actuator 51 has a vent 53
Is provided so that the dust that has flowed in can be discharged from the vent 53.

 FIG. 8 is an explanatory view of a second embodiment of the present invention.

In this embodiment, two openings serving as ventilation holes are provided.

For example, when the suction is performed in the direction A, when the rotational direction of the disk 9 is C, S (A, C) and S '(A, C)
An opening is provided at a location.

In this case, S '(A, C) serves as an inflow side vent, and S (A, C) functions as an exhaust side vent.

On the other hand, when the suction direction by the fan is opposite, that is, when the fan is drawn in the B direction, openings are provided at two locations indicated by S (B, C) and S ′ (B, C).

Thus, according to the second embodiment, by providing openings at two opposing positions of the actuator (for example, ten caps 36), a stronger airflow is formed in the direction connecting these openings than in the case of one opening. Thus, it is difficult for dust to flow deeper into the opening.

In FIG. 8, when the rotation direction of the disk 9 is reversed, when the retraction direction by the fan is the A direction, S
(A, C), S '(A, C), S (B, C), S' for B direction
(B, C) is good.

In the case where no fan is provided, the rotation direction of the disk 9 is a main factor for forming the airflow. In this case, the side closer to the tangential direction of the track (that is, in FIG. 8,
It is preferable to provide an opening in a direction orthogonal to the moving direction Ra of the optical pickup 3.

In addition, the inner and outer peripheral sides of the disk 9
Since the size of the airflow caused by the rotation of the cap 36 differs, it is conceivable to make the opening such as the cap 36 expanded in the circumferential direction.

Further, since the disk 9 is not always rotated, it is conceivable to widen the opening in the direction of drawing by the fan.

Further, depending on the structure inside the position where the opening is provided, changing the position of the opening may allow more airflow to be formed.

Further, for example, a fan may be provided on the side of the optical pickup 3 so that air can flow from one opening to the other opening to prevent dust.

Although not described in the above embodiments, a gap or an opening is usually provided at the lower part of the optical pickup. By closing these gaps and openings, the effect of the present invention becomes more remarkable. That is, the air pressure inside the housing is increased, and it is possible to make it difficult for outside air to enter.

As described above, the optical pickup of the present invention can be widely applied without depending on the structure of the optical pickup or other optical pickups.

[Effects of the Invention] As described above, according to the present invention, dust that has entered the movable member or the cover member is effectively discharged to the outside by the airflow flowing between the opening and another opening. Accordingly, it is possible to effectively prevent dust from adhering to the optical member and the like.

[Brief description of the drawings]

1 to 4 relate to a first embodiment of the present invention.
FIG. 2 is a side view showing a schematic configuration of the apparatus of the first embodiment, and FIG.
FIG. 3 is a perspective view showing the front panel, FIG. 3 is a plan view of the optical pickup viewed from above, FIG. 4 shows the structure of the actuator, FIG. 4 (a) is a plan view, and FIG. 5 (c) is a side view, FIG. 5 is an explanatory view for explaining a modification of the first embodiment, FIG. 6 shows the structure of another actuator, and FIG. 6 (a) is a plan view and FIG. (B) is a partially cutaway side view, (c) is a side view showing a cap portion provided with a vent, FIG. 7 shows still another actuator structure, and FIG. FIG. 8 (b) is a plan view, FIG. 8 (b) is a side view, FIG. 8 (c) is a side view showing a lens frame provided with a vent, FIG. 8 is an explanatory view for explaining a second embodiment of the present invention.
FIG. 9 shows an optical pickup in a conventional example, FIG. 9A is a sectional view, and FIG. 9B is an arrangement view showing an optical system. DESCRIPTION OF SYMBOLS 1 ... Optical disk apparatus, 2 ... Device housing 3 ... Optical pickup, 4A ... Turntable 9 ... Disk, 10 ... Actuator 15 ... Vent, 17 ... Exhaust port 19 ... Fan, 21 ... … Objective lens 36… Cap, 37… Vent

Continuation of the front page (56) References JP-A-61-233438 (JP, A) JP-A-62-298074 (JP, A) JP-A-63-42086 (JP, A) , U) Fully open sho 60-20028 (JP, U) Fully open sho 60-77029 (JP, U) Fully open sho 60-93125 (JP, U)

Claims (1)

(57) [Scope of request for utility model registration] An objective lens that moves in a radial direction of a recording medium and converges and irradiates the recording medium; an objective lens driving unit that controls an irradiation position of a light beam on the recording medium; A movable member including at least a part of an optical member that connects an optical path between the generation element and the light detection element; and a cover that covers the movable member and has an opening formed in a portion facing the objective lens. A member, and another opening different from the opening is formed in the movable member or the cover member, and at least one of the opening and the other opening is formed in the movable member and the cover member. An optical recording / reproducing apparatus having an optical pickup communicated through the other opening, wherein the other opening is provided only in a direction of an air flow caused by rotation of the recording medium on the objective lens, or Optical recording and reproducing apparatus, characterized in that it is formed only along the direction of the air flow by combining the air flow by the air flow and the fan by the rotation of said recording medium on the objective lens.