JPH03116477A - Optical disk player - Google Patents

Abstract

PURPOSE:To prevent the contamination of the objective lens of an optical pickup device which faces a disk loading part at the time of exchange of a disk and the generation of the reading errors of signals by positioning the objective lens in such a manner that the fingers hardly touch the object lens. CONSTITUTION:The optical pickup device 46 is transferred and operated in the state inclining to a front surface 23 of a housing 21 disposed with various operating parts. The objective lens 47 is, therefore, arranged in the position where the fingers gripping the optical disk 22 hardly face the objective lens at the time of attaching/detaching the optical disk 22 to/from the disk device part 66 constituted on the upper face of the housing 21. The objective lens 47 is positioned to the position apart from the position 23 provided with the operating part to release the cap body 21 even at the time of releasing and operating the cap body 21 covering the disk device part 66. The careless touch with the fingers is, therefore, prevented. Thus, the contamination of the objective lens 47 is prevented and the reading errors are eliminated.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention irradiates a laser beam emitted from a laser light source such as a semiconductor laser onto an optical disk on which information signals such as music audio signals and video signals are recorded. The present invention relates to an optical disc player that reads and reproduces the above information signals.

[Conventional technology]

The optical disc player has a disc table that is rotationally driven by a spindle motor, and an optical disc is mounted on this disc table and rotated, and an optical book-up device containing a semiconductor laser is installed on the inner circumferential side of the optical disc. The laser beam emitted from the semiconductor laser is irradiated perpendicularly from the bottom side of the optical disk to the recording track so that the laser beam is caused to travel in the normal direction of the recording track formed on the optical disk from the bottom side to the outer circumferential side of the optical disk. , and is configured to read and reproduce a predetermined information signal recorded on this recording trunk.

On an optical disc, which is a signal recording medium used in an optical disc player with such a configuration, information signals such as audio signals are pulse-coded and recorded at high density as pit rows with minute irregularities. For so-called compact discs on which signals are recorded, the diameter is 12
The size set to c+m is used as the standard size. Since the optical discs used as recording media in optical disc players for musical sound playback are of small diameter, attempts have been made to make the optical disc players themselves smaller and thinner. As shown in FIG. 1, it has been considered that the inner circumferential shape of an exterior housing 1 is reduced to a rectangular size such that the outer circumferential diameter of an optical disk 2 substantially forms an inscribed circle. Furthermore, in order to reduce the thickness of the optical disc player, an optical book-up device 3 configured as shown in FIG. 2 is used. This optical pickup device 3 focuses a laser beam and irradiates the signal recording surface of the optical disk 2 perpendicularly to the optical axis of an objective lens 4. A laser beam is emitted from a semiconductor laser 6 in parallel to
It is configured to lead out to the objective lens 4 through.

Therefore, in this optical pickup device 3, the semiconductor laser 6 is attached to the end of the housing 18 so that the laser beam is emitted in a direction perpendicular to the optical axis of the objective lens 4, and the laser beam is used for signal reading. A diffraction grating 9 separates the main beam into a main beam and two sub-beams for tracking servo, a beam splitter 10 separates and guides the return beam reflected from the optical disk 2 to the photodetector 12, and controls the laser beam into parallel light. An optical system block including a collimating lens 11 and the like is assembled in the housing 18 so that its front axis is orthogonal to the optical axis of the objective lens 4. Also, beam splinter 10
An optical system block consisting of an intermediate lens 13, a cylindrical lens 14, etc., guides the returned light beam reflected from the optical disk 2 in a 90-degree direction and read the information signal recorded on the optical disk 2 to the photodetector 12. The axis is also incorporated into the housing 18 so as to be orthogonal to the optical axis of the objective lens 4. The optical pickup device 3 configured so that the laser beam emitted from the semiconductor laser 6 enters the objective lens 4 from a direction perpendicular to the tip axis thereof, allows the laser beam 1 to be incident from the optical axis direction of the objective lens 4. The optical pickup device 3 can be made sufficiently thinner than the incident device, and the optical disc player to which this optical pickup device 3 is attached can also be made thinner.

[Problem to be solved by the invention]

As mentioned above, the exterior housing 1 is made smaller and the optical pickup device 3 disposed inside this exterior housing 1 is made thinner.
Although it is conceivable to make the device as a whole smaller and thinner, conventionally proposed optical disc players have an optical pickup device 3 mounted on an exterior wall of a rectangular exterior casing 1, as shown in FIG. The recording track is traced by a laser beam transmitted from the objective lens 4 from the inner circumferential side to the outer circumferential side of the optical disk 2 mounted on the disk table. The apparatus is configured to obtain an information signal recorded on the track. That is, the optical pick-up device 3 directs the optical axis of the objective lens 4 to the optical disc 2 placed on the disc table via a pair of guide shafts 16 and 17 arranged parallel to the exterior wall 15 of the exterior housing 1. It is configured to be movably attached to the center line of the image forming apparatus, and to be transferred by a transfer means including a drive motor (not shown).

By the way, as mentioned above, in an optical disc player that is downsized to a rectangular size in which the outer circumferential diameter of the optical disc 2 is approximately the inscribed circle, approximately the entire upper surface side of the exterior housing 1 is the disc mounting part. 20. The disk mounting section 20 is closed with a lid body so as to be opened so that the optical disk 2 can be inserted and removed. The objective lens 4 of the optical pickup device 3 that transmits the laser beam onto the optical disk 2 faces the disk mounting section 20 . Therefore, when the disk mounting portion 2o is opened and the optical disk 2 is loaded or unloaded, there is a risk that the objective lens 20 may be touched by fingers and the objective lens 2° may be soiled.

In particular, in the case where the optical pick amplifier device 3 is mounted so as to be moved parallel to the front wall portion 1a of the exterior housing 1 as shown in FIG. The objective lens 4 is located on the side facing the fingers that are grasping it. If the objective lens 4 is touched and soiled by fingers, it will cause diffused reflection of the transmitted laser beam, causing reading errors in the read information. It could become a problem.

Therefore, the present invention prevents dirt on the objective lens by making it difficult for fingers to come into contact with the objective lens of the optical pickup device that faces the disk mounting section when replacing the disk, thereby preventing the occurrence of errors in reading information signals. This was proposed for the purpose of providing an optical disc player that can perform the following functions.

[Means to solve the problem]

Therefore, in order to achieve the above-mentioned object, the optical disc player according to the present invention includes a disc rotation driving means for rotationally driving an optical disc placed thereon, and a disc rotation driving means for rotating the optical disc placed on the optical disc, and a disc rotation driving means for rotating the optical disc placed on the optical disc, and a disc rotation driving means for rotating the optical disc placed on the optical disc, and a disc rotation driving means for rotating the optical disc placed on the optical disc. a casing housing an optical pickup device for performing the above-mentioned operations, and an operation section provided on the front side of the casing, the feeding direction of the optical pickup device being in a radial direction centered on the disk rotation driving means, and The direction is non-parallel to the front surface of the housing.

[Effect]

In the optical disc player according to the present invention, the optical pickup device is transferred while being inclined with respect to the front surface of the casing. Furthermore, since the optical pickup device is transported in an inclined state with respect to the front surface of the casing, the objective lens can be placed at a position separated from the operating section disposed on the front side.

〔Example〕

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

As shown in FIG. 3, FIG. 4, and FIG. 5, the optical disc player according to the present invention has an inner circumferential shape of an exterior casing 21 constituting the player body, and an outer circumferential shape of an optical disc 22 to be played by this player. The optical disc 2 has a rectangular shape with a radius R as an inscribed circle, that is, one side of the inner peripheral edge of the exterior housing 21 is
It is formed into a rectangular shape with a length approximately equal to the diameter of 2. Front side exterior wall portion 23 of exterior casing 21 formed in this way
The operation section of this optical disc player includes a power switch operation button 24, a play/pause button 25, a next song selection button 26, a fast forward operation button 27, a designated song selection section 28, a reverse operation S port 29, and Six operating ports such as an eject button 30 and a display section 31 for displaying a timer or the address of the music to be performed are provided.

A disk rotation drive mechanism for rotationally driving the optical disk 22 is arranged in the center of the exterior housing 21 . This disk rotation drive mechanism is arranged such that the axis of a spindle 33 substantially coincides with the center of the exterior housing 21, and integrally includes a disk table 32 on which the optical disk 22 is placed on the tip side of the spindle 33. It is installed. The spindle 33 is connected to the chassis board 3 as shown in FIG.
A thrust bearing 36 is inserted into and rotatably supported by a bearing 35 attached to the bottom side of the chassis board 34, and is also attached so as to hang down from the bottom side of the chassis board 34.
The tapered base end 33a is supported and attached to the base end 33a. A disk plate 37 made of metal and formed into a disk shape is integrally fitted to the base end side of the spindle 33 mounted in this manner. An elastic ring 39 made of an elastic material such as rubber is fitted into a fitting portion 38 formed by cutting out a step-like outer peripheral portion of the upper surface of the disk plate 37 facing the disk table 32. . This elastic ring 3
The upper surface of 9 is formed into a tapered drive wheel contact surface 40, and is connected to the output shaft of a drive motor 42 attached parallel to the surface of the optical disk 22 via a motor support member 41 attached to the lower surface side of the chassis board 34. A drive wheel 4 is attached to a drive shaft 44 connected via a reduction gear mechanism 43 and has an outer circumferential surface formed into a tapered surface corresponding to the drive wheel contact surface 40.
5 are in rolling contact so that the rotational driving force of the drive motor 42 is transmitted to the spindle 33.

In this way, by adopting the so-called disk drive method in which the drive wheel 45 driven by the drive motor 42 is brought into rolling contact with the upper surface of the disk plate 37 attached to the base end side of the spindle 33 to drive the spindle 33,
Since the output shaft of the drive motor 42 can be mounted parallel to the surface of the optical disk 22 mounted on the disk table 32, the spindle drive mechanism can be made thinner, which in turn contributes to making the optical disk player thinner.

Note that the drive method for the disk table 32 is not limited to the above-described disk drive method, but may also employ a so-called direct drive method in which the spindle 33 is directly connected to the output shaft of a drive motor.

Inside the exterior housing 21 in which the disc table 32 is arranged as described above, a laser beam is irradiated onto the signal recording surface of the optical disc 22 mounted on the disc table 33, and musical tone signals recorded on the optical disc 22 are recorded. An optical pickup device 46 for reading and operating information signals such as the above is attached with an objective lens 47 facing the signal recording surface of the optical disc 22. This optical pickup device 46 is
Front side exterior wall portion 2 provided with various operation buttons etc. of the exterior housing 21
3 in the radial direction about the center of rotation of the optical disc 22 at an angle inclined to the rear side exterior wall 48 parallel to the front side exterior wall 23 and the opposing both side exterior walls 49 and 50. It is attached so that it can be operated to run from the inner circumferential side to the outer circumferential side of the optical disc 22.

By the way, the optical pickup device 4 used in the present invention
6 as well, in order to make it thinner, like the one used in the optical disc player shown in FIGS. 1 and 2 mentioned above,
The laser beam is configured to be incident on the objective lens 47 from a direction perpendicular to its optical axis 08. That is, as shown in FIGS. 7(A) and 7(B), a laser beam emitted from a semiconductor laser 51 as a light source is aligned with the optical axis of the objective lens 47 at 0. A diffraction grating 54 is attached to the end of the housing 52 so that the laser beam is emitted in a direction perpendicular to l, and the diffraction grating 54 separates the laser beam into a main beam for signal reading and two sub beams for tracking servo. An optical system block consisting of a beam splinter 56 that reflects the laser beam to the photodetector 55, a collimating lens 57 that polarizes the laser beam into parallel light, etc. is arranged with its optical axis 0. is assembled into the housing 52 so that it is orthogonal to the optical axis of the objective lens 47,
The optical disc 2 is also refracted in a 90 degree direction by the beam splitter 56 and reflected from the optical disc 22.
The optical axis O2 of the optical system block on the return destination side, which is made up of a semicylindrical lens 59 that reads the information signal recorded on the lens 2 and guides the returned light to the photodetector and astigmatizes the returned light, is also the same as the optical axis O2 of the objective lens 47. Optical axis 0. It is incorporated into the housing 52 so as to be orthogonal to the housing 52 .

The laser beam emitted from the semiconductor laser 51 is reflected by a reflecting mirror 60 attached to the lower surface side of the objective lens 47.
After the optical path is deflected in the 90 degree direction, the polarization axis is
The light is perpendicularly incident on the objective lens 47 via the 1/4 wavelength Fi 61 which rotates on the degree axis.

Further, an objective lens 47 that focuses the laser beam emitted from the semiconductor laser 51 and irradiates it perpendicularly to the signal recording surface of the optical disk 22, or transmits the return light reflected from the signal recording surface, The objective lens 47 is supported by a two-axis drive device 65 that drives the objective lens 47 in two mutually orthogonal axes, namely, a focus direction and a recording track tracking direction that is orthogonal to the optical axis direction. The objective lens 47
is supported by the two-axis drive device 65,
Focus control is performed so that the recording track is positioned within the focal depth of the laser beam, and tracking control is performed so that the laser beam accurately traces the recording track.

In the optical pickup device 46 configured as described above, when the optical pickup device 46 is transported so as to trace the outermost recording track of the optical disk 22, the objective lens 47, which has a large external shape, is supported movably in two axial directions. The two-axis drive device 65 is located at a corner formed by the rear exterior wall 48 of the exterior housing 21 and one side exterior wall 49 perpendicular to the rear exterior wall 48 of the exterior casing 21, and the two-axis drive device 65 is located at a corner formed by the rear exterior wall 48 of the exterior housing 21 and one side exterior wall 49 perpendicular thereto. The optical axis between the mirrors 60 is approximately parallel to the rear side exterior wall 48, that is, the laser beam is aligned with the disk table 3.
The semiconductor laser 51 is arranged in the exterior housing 21 so that the semiconductor laser 51 emits light parallel to the surface of the optical disk 22 placed on the optical disc 22 and parallel to the rear exterior wall 48 .

By the way, tracking of recording tracks by the laser beam irradiated onto the signal recording surface of the optical disk 22 through the objective lens 47 traces all the recording tracks from the inner circumference side to the outer circumference side of the optical disk 22. It is necessary to perform this in the normal direction of the recording track. Therefore,
The optical pickup device 46 arranged as described above is
The objective lens 47 is mounted in the exterior housing 21 so as to be moved in the normal direction of the recording track, that is, in the radial direction passing through the center of the optical disk 22. That is, the optical pickup device 46 has slide bearings 54 and 55 fitted in the housing 52 and mounted on a pair of guide shafts 101 and 102 mounted on the chassis substrate 34 in parallel to the direction in which the objective lens 47 is to be transported. The recording track of the optical disk 22 is completely tracked from the inner circumferential side to the outer circumferential side by being inserted and attached and being guided and transported by the guide shafts 101 and 102.

The pair of guide shafts 101 and 102 that guide the optical pickup device 46 disposed inside the exterior casing 21 and operated in a transfer operation are installed at an angle with respect to the rear exterior wall 48. If so, the inclination angle θ is approximately 45 degrees.
It is attached onto the chassis board 34 with the following steps.

By transporting the optical pickup device 46 at an angle with respect to the rear side exterior wall portion 48 of the exterior housing 21, the optical axis of the objective lens 47 is aligned with the optical disc 2.
The two-axis drive device 65, which becomes large when reaching the outermost recording track No. 2, can be positioned protruding from the corner formed by the rear exterior wall 48 and one side exterior wall 49. , the recording track from the inner circumferential side to the outer circumferential side of the optical disk 22 can be tracked without increasing the size of the rectangular exterior housing 21 whose inscribed circle is the outer circumferential edge of the optical disk 22.

The pair of guide shafts 101 and 102 are formed by cutting and raising a part of the chassis board 34, and are mounted by inserting and supporting both ends into the insertion holes of the piece 103. The shaft 101 is fixedly mounted with high precision so that the optical pickup device i46 can be accurately positioned in the running direction, and the other guide shaft 102 is attached to the one guide shaft 101 due to errors and optical pickup device 46. The bearing is mounted in such a way that its condition can be adjusted to absorb errors in machining accuracy of the bearing.

As described above, the slide bearing 10 is attached to the pair of guide shafts 101 and 102 that are arranged obliquely with respect to the rear side exterior wall 48.
4. The optical pickup device 46 is slidably attached via 105, and the motor support member is mounted on the lower surface side of the chassis board 34 so that the output shaft 106 is parallel to the exterior wall 49 on one side of the exterior housing 21. A pickup drive motor 108 attached via a pickup drive motor 107 moves the optical disc 22 from the inner circumference side to the outer circumference side. The pickup drive motor 108 and the optical pickup device 46 are connected to the output shaft 1 of the drive motor 108.
The worm gear 109 attached to the optical pickup device 46 and the guide shaft 101 are attached to one side of the housing 52 of the optical pickup device 46.
, 102, the rack 110 is mounted parallel to the
A connecting gear mechanism 114 consisting of mutually meshed first, second, and third gears 111, 112, and 113 constituting a deceleration mechanism is disposed between them, and the driving force of the pickup drive motor 10B is decelerated. The signal is transmitted to the optical pickup device 46, and the optical pickup device 46 is operated to travel.

The exterior housing 21 also includes a lid 6 that covers the mounting portion 66 of the optical disc 22 configured on the upper surface side of the exterior housing 21.
7 is installed. The lid body 67 has its base end supported by the rear exterior wall 48 via a rotation hinge 68, and is rotatably attached to open and close the disk mounting portion 66. In addition, an optical disc 22 that is placed on the disc table 32 is sandwiched in the center of the inner surface of the lid 67 in cooperation with the disc table 32, and the optical disc 22 is integrated with the disc table 32. A chucking member 69 is rotatably mounted to allow rotation.

In the optical disc player configured as described above, the optical pickup device 46 is arranged in a radial direction centered on the spindle 33 of the disc rotation drive device, and is mounted on the outer housing 21.
Since the objective lens 47 of the optical pickup device 46 is moved in an inclined direction non-parallel to the front side exterior wall 23 of It can be located on the corner side of 21. In particular, in the embodiment described above, the lid body 67
The objective lens 47 can be positioned on the corner portion side of the rear side exterior wall portion 48 side where is supported. Therefore, as shown in FIG. 8, the lid 67 is opened and the disc mounting section 6
When the optical disk 22 is attached to and removed from the optical disk 6, it becomes difficult for the fingers holding the optical disk 22 to touch the objective lens 47. Moreover, not only when attaching and detaching the optical disc 22, but also when opening the cover body 47 by operating the eject button 30 in the operating section provided on the front side exterior wall 23, the monster lens 47 is located at a position separated from the front side exterior wall portion 23 where the operating section is disposed, so that inadvertent contact with fingers is prevented.

Furthermore, since the optical pickup device 46 is made to travel at an angle inclined to the rear side exterior wall portion 48 of the exterior housing 21, the optical axis of the objective lens 47 is aligned with the optical disc 22.
The two-axis drive device 65, which becomes large when reaching the outermost recording track, can be positioned at the corner of the outer housing 21, and the outer housing 21 has a rectangular shape with the outer peripheral edge of the optical disc 22 as an inscribed circle. This enables miniaturization.

〔Effect of the invention〕

As described above, the present invention is configured such that the optical pickup device is transferred in a state inclined with respect to the front surface of the casing in which various operation sections are disposed, so that the disk mounting configured on the top surface of the casing is not possible. The objective lens can be located at a position where the fingers gripping the optical disc are difficult to reach when loading and unloading the optical disc into the optical disc. Furthermore, when opening the lid that covers the disk mounting section, the objective lens can be positioned away from the position where the operating section for opening the lid is located, preventing inadvertent contact with fingers. It can be prevented.

Therefore, it is possible to avoid touching the objective lens with fingers and fingers when loading and unloading the optical disk or when operating the operating section, thereby preventing the objective lens from being soiled, and making it possible to construct an optical disk player free from reading errors.

[Brief explanation of drawings]

FIG. 1 is a plan view showing an optical disc player, which is the premise of the present invention, and FIG. 2 is a schematic sectional view showing an optical pickup device used in the optical disc player. FIG. 3 is a perspective view showing an optical disc player according to the present invention, FIG. 4 is a plan view thereof, and FIG. 5 is a bottom view thereof. FIG. 6 is a side view showing a drive mechanism for a disc table constituting the optical disc player. FIG. 7 shows an example of an optical pickup device used in the optical disc player, and FIG.
) is a sectional view taken along line AA in FIG. 5, and FIG. 7(B) is a sectional view taken along line BB in FIG. FIG. 8 is a perspective view of the optical disc player showing the loading/unloading state of the optical disc. 21-----・-- Exterior casing 23-------------Front side exterior wall 24
−−−−−−−・−・Power switch operation button 30−・−
...Eject button 32--Disc table 33-m--Spindle 46--Optical pickup device 47--
・・Objective lens 66 --- Disk mounting part 67 --- Lid body

Claims (1)

[Scope of Claims] A casing that houses a disc rotation driving means for rotationally driving an optical disc placed thereon, and an optical pickup device for reading information recorded on the optical disc; and a front surface of the casing. an operating section provided on the side, and the optical pickup device is fed in a radial direction centered on the disk rotation drive means, and in a direction non-parallel to the front surface of the housing. disc player.