JP4153336B2 - Recording / playback device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
According to the present invention, an optical pickup for optically recording and / or reproducing (recorded / reproduced) on a recording medium by concentrating a light beam with an objective lens is provided on a disk tray on which the recording medium is installed. In addition, the present invention relates to a recording / reproducing apparatus provided with an optical sensor for detecting an angle between a recording medium and an objective lens.
[0002]
[Prior art]
FIG. 9 is a configuration diagram of a general optical pickup. Light beams emitted from the semiconductor laser units 1a and 1b are collimated by collimating lenses 2a and 2b, and condensed by an objective lens 4 through a beam splitter 3. Then, it is irradiated as a minute light spot on the optical disk 5 as a recording medium. The reflected light from the optical disk 5 returns to the inside of the semiconductor laser units 1a and 1b again through the objective lens 4 and the beam splitter 3. The reflected light from the optical disk 5 that has returned to the inside of the semiconductor laser units 1a and 1b is diffracted by a hologram element provided in the semiconductor laser units 1a and 1b, and is condensed and photoelectrically converted to a light receiving element (not shown). The signal is calculated and output as a control signal and a recording / playback signal.
[0003]
The position control of the light spot is performed by the signal, and the position control information of the light spot is fed back to an actuator (not shown) on which the objective lens 4 is mounted, so that proper focusing and tracking are always performed. .
[0004]
The objective lens 4 is generally provided in the actuator and is movable only in the focus direction and the track direction. After the optical pickup is tilt-adjusted when the optical pickup is assembled, the objective lens 4 is incorporated into the optical pickup and fixed. Is done. Thus, conventionally, in a general configuration, the angle correction between the optical disc 5 and the objective lens 4 is not performed, and recording / reproduction is performed in the initial adjustment state as described above.
[0005]
However, in recent years, with the increase in the density of optical discs, the angle margin between the optical disc and the objective lens has decreased, and it has become necessary to individually perform tilt correction within individual optical discs or within the optical disc plane.
[0006]
For this reason, as described in Patent Document 1, a tilt sensor (optical sensor) for detecting the angle between the optical disc and the optical pickup is separately provided on the optical pickup, and the output from the optical sensor is monitored. There is a tendency to adopt a configuration in which the objective lens or the entire optical pickup is tilted according to information and the relationship with the optical disc is always kept optimal.
[0007]
In general, the optical sensor emits a laser diode as a light emitting element provided inside, and an optical change in reflected light from the optical disk is detected by a light receiving element such as a photodiode provided in the inside. After the photoelectric conversion, the tilt angle is detected by calculating appropriately.
[0008]
[Patent Document 1]
JP 2002-251760 A [Patent Document 2]
Japanese Patent Laid-Open No. 2002-124071
[Problems to be solved by the invention]
However, conventional general optical sensors are prone to problems due to contamination on the surface due to their structure, and are built into a drive that is mounted on a notebook personal computer and the optical pickup is exposed outside the device. When an optical sensor is provided on a disc tray (see Patent Document 2), there is a high possibility that dust or the like will adhere to the disc tray. Is done.
[0010]
Furthermore, when the optical pickup is exposed to the outside of the apparatus together with the optical sensor, there is a risk of exposure such as a light beam from a laser diode constituting the optical sensor entering the eyes of the user.
[0011]
The present invention solves the above-described conventional problems, and protects the mounted optical sensor and prevents an inadvertent emission of the light beam even when the optical pickup is exposed to the outside when the disk is taken out. Thus, it is possible to provide a recording / reproducing apparatus that can prevent erroneous detection of an optical sensor, always realize high-quality recording / reproducing, and prevent exposure of a light beam to a user. Objective.
[0012]
[Means for Solving the Problems]
In order to achieve the above object, according to the first aspect of the present invention, there is provided a light for optically recording / reproducing light on a recording medium by focusing a light beam on a disk tray on which the recording medium is set by an objective lens. In a recording / reproducing apparatus provided with a pickup and a moving mechanism for moving the optical pickup along the recording surface of the recording medium, the disk tray is installed so as to be able to enter and exit from the apparatus main body. An optical sensor for detecting an angle with the objective lens is installed in the optical pickup, and a long hole for entering and exiting the optical sensor in a part of a cover body provided so as to cover a part of the optical pickup the provided, when the optical pickup along with the disc tray comes into the outside from the apparatus main body, to move the optical pickup inward or outward, the light Sensor is characterized by being configured so as to disengage from the slots.
[0017]
With the above-described configurations, even if the optical sensor is exposed to the outside of the apparatus together with the optical pickup, the optical sensor is shielded from the outside and protected from dust and the like. In addition, sensor malfunction due to dirt, etc. can be prevented with a simple structure, and it is possible to prevent the light beam from being accidentally emitted from the optical sensor. Recording / reproduction quality corresponding to high-density recording can be stably obtained.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0019]
FIG. 1 is an exploded perspective view of an optical disk device for explaining an embodiment of the present invention, 11 is a lower case made of sheet metal, 12 is attached to the lower case 11 and covers the upper opening of the lower case 11. An upper case 13 constituting the main body is a disk tray on which an optical disk (not shown) as a recording medium is installed. The optical disk is ejected by a pair of rail members 14 installed on both sides of the lower case 11. It is guided so as to be reciprocable and slidable between the position to be loaded and the position to be loaded.
[0020]
Below the central hole portion 13a of the disc tray 13 is the configuration described with reference to FIG. 9, and an optical pickup 15 for optically recording / reproducing by condensing the light beam on the optical disc, and the optical disc. A unit body 18 including a spindle motor 16 that rotates and a moving mechanism 17 that moves the optical pickup 15 in the radial direction of the optical disk during recording / reproduction is installed. The unit body 18 is made of a sheet metal that covers the lower surface of the disk tray 13. It is held on the disc tray 13 via the bottom plate member 19.
[0021]
The central hole 13 a of the disc tray 13 is covered with a cover plate 20 except for the disc chucking portion of the spindle motor 16 and the movement area of the optical pickup 15. Further, the cover plate 20 is provided with a long hole 22 for light incident / exit of a tilt sensor 21 which is an optical sensor installed at the upper part of the optical pickup 15. The tilt sensor 21 includes a light emitting element 23 made of a laser diode or the like and a light receiving element 24 made of a photodiode or the like.
[0022]
A front panel 25 provided with an eject button 26 that is pressed when the disc tray 13 is ejected is attached to the front of the disc tray 13. By pushing the eject button 26, the disc tray 13 is driven to move between a loading position in the apparatus main body and a discharge position outside the apparatus main body.
[0023]
FIG. 2 is a perspective view showing a planar state of the unit body in the present embodiment, in which 27 is a first chassis, 28 is a second chassis joined and fixed to the first chassis 27, and 29 is a disk radius of the optical pickup 15. A guide shaft 30 that guides the movement in the direction, 30 is arranged in parallel to the guide shaft 29 and drives the optical pickup 15 to move, 31 drives the lead screw 30, and the guide shaft 29 and the lead screw 30. And a drive motor constituting the moving mechanism 17 of the optical pickup 15.
[0024]
In the embodiment having the above configuration, at the time of recording / reproducing, the optical pickup 15 is moved in the radial direction of the optical disc by the moving mechanism 17 as shown in FIG. 3, and the tilt sensor 21 is also moved in the radial direction of the optical disc together with the optical pickup 15. To do. The tilt sensor 21 emits light from the light emitting element 23 to the optical disk and receives the reflected light from the optical disk by the light receiving element 24, so that the optical disk and the objective lens in the optical pickup 15 are in each part on the recording surface of the optical disk. A tilt control signal (tilt adjustment signal) is detected.
[0025]
In response to the tilt control signal, a tilt control mechanism (not shown) is driven to adjust the relative tilt between the optical pickup 15 including, for example, an objective lens, and the spindle motor 16 including a chucking unit on which an optical disk is placed, Thus, the angle of the objective lens with respect to the optical disc is adjusted so that the tilt angle is within the allowable angle range.
[0026]
In the present embodiment, the optical pickup 15 is driven by the moving mechanism 17 and moves to a position where the tilt sensor 21 is retracted to the lower part of the cover plate 20 that is removed from the long hole 22 as shown in FIG. ing. In the state shown in FIG. 4, the tilt sensor 21 is shielded from the outside by the cover plate 20, thereby protecting the light emitting element 23 and the light receiving element 24, and the tilt sensor 21 does not emit light from the light emitting element 23 to the outside. So that the light is blocked.
[0027]
In the configuration of the present embodiment, the optical pickup 15 is also exposed to the outside of the apparatus body at the same time when the disc tray 13 goes out of the apparatus body at the time of ejection. There is a risk that the tilt sensor 21 may be touched or dust may be attached. For this reason, when the disc tray 13 goes outside the apparatus main body, the sensor (light emitting element 23) is moved by moving the tilt sensor 21 to the lower part of the cover plate 20 as described above and maintaining the shield state against the outside. , Dirt and dust can be prevented from adhering to the light receiving element 24), and the user can be protected from being exposed to light so as not to emit light from the light emitting element 23 to the outside.
[0028]
In this way, in this embodiment, it is possible to reduce the occurrence of sensor operation errors and offsets without adding new members to the conventional apparatus, and it is possible to safely and stably perform high-quality recording / reproduction. Is possible.
[0029]
FIG. 5 is a block diagram showing a schematic configuration of a control system related to tilt sensor shielding in the present embodiment. A signal 33 such as an ON signal of various sensors 34 and the eject button 26 is input, and a control signal is sent to each part. A CPU (central processing unit) 35 serving as a control means for outputting is a pickup moving mechanism driving unit that drives a moving mechanism 17 that moves the optical pickup 15.
[0030]
The tilt sensor shielding operation in this embodiment will be described with reference to the flowchart of FIG. In the present embodiment, when the CPU 33 receives the ON signal of the eject button 26 (YES in S1), it outputs a drive signal so that the disc tray 13 comes out of the apparatus main body. At the same time, a drive signal is output to the pickup moving mechanism drive unit 35 to start the moving mechanism 17 and move the optical pickup 15 (S2). The optical pickup 15 moves together with the tilt sensor 21, and as shown in FIG. 4, the tilt sensor 21 moves to a retracted position (sensor shielding portion) in the lower part of the cover plate 20 removed from the long hole 22, and stops ( S3).
[0031]
In the configuration shown in FIG. 4, the sensor shielding position on the cover plate 20 is set on the inner side in the moving direction of the optical pickup 15, but the sensor shielding position on the cover plate 20 is set as shown in FIG. Alternatively, the outer side of the optical pickup 15 may be set.
[0032]
Further, depending on the movable range of the optical pickup 15, the sensor shielding position is set on the outer peripheral side of the disc tray 13 outside the installation range of the cover plate 20 or on the inner peripheral side as shown in FIG. It can be considered.
[0033]
Further, as described above, the installation position of the tilt sensor 21 in the optical pickup 15 is appropriately changed according to the setting of the sensor shielding position.
[0034]
【The invention's effect】
As described above, according to the present invention, even in a recording / reproducing apparatus configured such that the optical sensor is exposed to the outside of the apparatus together with the optical pickup, the optical sensor is shielded from the outside and dust or the like is attached. Therefore, it is possible to prevent the malfunction of the sensor due to dirt or the like with a simple configuration and to prevent the light beam from being accidentally emitted from the optical sensor. Therefore, it is possible to provide a recording / reproducing apparatus that can stably obtain recording / reproducing quality corresponding to low-cost and small-sized high-density recording, and is excellent in reliability and safety.
[Brief description of the drawings]
FIG. 1 is an exploded perspective view of an optical disc apparatus for explaining an embodiment of the present invention. FIG. 2 is a perspective view showing a planar state of a unit body in the present embodiment. FIG. 4 is a plan view showing the main part for explaining the operation of the optical pickup. FIG. 4 is a plan view showing the main part when the sensor is shielded in this embodiment. FIG. 5 is a schematic configuration of a control system related to tilt sensor shielding in the present embodiment. FIG. 6 is a flowchart relating to a tilt sensor shielding operation in the present embodiment. FIG. 7 is a plan view for explaining another example of the sensor shielding unit in the embodiment. FIG. 8 is a sensor shielding unit in the embodiment. Plan view for explaining another example [FIG. 9] Configuration diagram of an optical system of a general optical pickup [Explanation of symbols]
13 Disc tray 15 Optical pickup 16 Spindle motor 17 Moving mechanism 20 Cover plate 21 Tilt sensor 22 Long hole 26 Eject button 33 CPU
35 Pickup moving mechanism drive

Claims (1)

An optical pickup for condensing a light beam by an objective lens and optically recording / reproducing on the recording medium on a disk tray on which the recording medium is installed, and the optical pickup along the recording surface of the recording medium In a recording / reproducing apparatus provided with a moving mechanism for moving, wherein the disk tray is installed so as to be able to enter and exit the apparatus main body.
An optical sensor for detecting the angle between the recording medium and the objective lens is installed in the optical pickup, and the optical sensor enters and exits a part of a cover body provided to cover a part of the optical pickup. the long hole of use provided, when the optical pickup along with the disc tray comes into the outside from the apparatus main body, to move the optical pickup inward or outward, so that the optical sensor is out of the long hole The recording / reproducing apparatus characterized by the above-mentioned.

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