JPH04216337A - Optical disk device - Google Patents

Abstract

PURPOSE:To surely prevent the damage to the recorded data on an optical disk at the time of deciding the output of a light beam and to execute the stable read, write and erasure of the data. CONSTITUTION:In an optical disk device which is provided with an optical head 3 for focusing the light beam on a recording medium and executes the readout and the write of recorded data on the recording medium, the output of the light beam which is radiated by the head 3 is decided in a state where the head 3 is held by a holding means 12 at an inner periphery side or an outer periphery side from the recording performable track of the optical disk 1.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to control of the light beam output of an optical disk device that is equipped with an optical head that focuses a light beam onto an optical disk as a recording medium and reads and writes information on the recording medium.

0002

2. Description of the Related Art In an optical disk device that uses an optical disk as a recording medium, it is necessary to adjust the light beam output during reading, writing, and erasing. For this purpose, a laser beam emitted from a laser diode (hereinafter referred to as LD) within the optical head is received by a light beam detector also within the optical head to set the control section.

[0003] Such adjustment of the light beam output is performed after the optical head is moved to the innermost or outermost circumference outside the recording track area of the optical disc. In this case, the light beam is in a defocused state.

Furthermore, the light beam output is controlled by adjusting the voltage or current applied to the LD.

[0005]

[Problem to be solved by the invention] When adjusting the light beam output as described above, it is necessary to fix the optical head (
(maintained) has not been carried out. Therefore, the optical head may move to the recording track area due to external vibrations.

[0006] In such a state, if a strong light beam for writing or erasing is emitted and is brought into focus for some reason, data in the recording track area may be destroyed.

[0007]Furthermore, when controlling the light beam output, the control circuit may fail, causing damage to the recorded data on the optical disc and the LD.

The present invention has been made with attention to these points, and its purpose is to reliably prevent the destruction of recorded data on an optical disk when determining the light beam output, and to ensure stable data reading, writing, and erasing. The object of the present invention is to provide an optical disc device that can perform the following operations.

[0009]

[Means for Solving the Problems] The present invention, which solves the above problems, is an optical disc device that is equipped with an optical head that focuses a light beam on an optical disc and reads and writes records on the optical disc. A holding means for holding the optical head on the inner or outer side of the track, a light output detection means for detecting the light output of the light beam emitted from the optical head, and a light beam output based on the detection result of the light output detection means. The invention is characterized by comprising: a light beam output control means for controlling the light beam output.

0010

In the present invention, the optical head is held in an area outside the recordable tracks of the optical disk, and in this state the light beam is emitted for controlling the light beam. At this time, since the optical head is fixed, the emitted light does not destroy data on the optical disk.

[0011]

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

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is an explanatory diagram showing a recording track area of an optical disk, and FIG. 3 is a block diagram of a mechanism for holding an optical head.

[0013] In these figures, an optical disc 1 has a recording track area 1b, an outer peripheral part 1a, and an inner peripheral part 1c, and is rotationally driven by a motor 2. The optical head 3 is
It is composed of an LD 3a as a light source, a light receiving element 3b that receives reflected light from the optical disc 1, and a light beam detector 3c that detects the intensity of the light beam, and is driven for tracking and focusing by a head drive mechanism, which will be described later, and by a holding mechanism. held in a fixed position. The output of the light beam detector 3c is converted into a voltage signal by a current/voltage converter 4, and further converted into digital data by an A/D converter 5. The comparison control unit 6 compares the preset value and A.
/D converter to control the light emission intensity (light beam output) of the LD. On the other hand, based on this comparison result, the determining section 7 performs on/off control of the LD 3a. The D/A converter 8 converts the output of the comparison control section 6 into a D/A converter 8.
A converter and then driver 9 and voltage-current converter 10
A current for driving the LD3a is generated.

The operation of the apparatus of this embodiment constructed as described above is as follows.

When the optical disc device is in the normal on state (usable state), the solenoid 12e is driven and the plunger 12 is moved against the biasing force of the spring 12f.
g is driven. As a result, the carriage fixing member 12
c is moved in a direction away from the carriage 3e, and the engagement between the notch groove 12d and the pin 12b is released,
The carriage 3e is in a movable state along guide rails 11e and 11f.

When adjusting the light beam output, the optical head 3 is adjusted so that the light beam from the optical head 3 irradiates areas other than the recording track area 1b of the optical disc 1.
is driven by the head drive mechanism 11.

That is, when current is supplied to the coils 11c and 11d, a thrust is generated in the coils 11c and 11d disposed in the magnetic gaps of the magnetic circuits 11a and 11b.
The carriage 3e is guided by guide rails 11e and 11f, moves in the radial direction of the optical disc, and accesses areas (1a, 1c) other than the recording track area.

Alternatively, when the optical head 3 is already in such a position, the head drive mechanism 11 does not drive.

The holding mechanism 12 holds the optical head 3.

At this time, the current supply to the solenoid 12e that was driving the carriage fixing member 12c against the biasing force of the spring 12f is turned off, and the pin provided in the notch groove 12d of the carriage fixing member 12c and the carriage 3e is turned off. 12, and free movement of the carriage 3e is prohibited.

In this state, in order to determine the light beam output,
Laser light is emitted from the LD3a. In this case, since the optical head 3 is held outside the recording track area, the optical head 3 will not move even if vibrations are applied from the outside. Therefore, the recorded data will not be destroyed by the laser beam.

Furthermore, even if the intensity of the laser beam increases abnormally for some reason, the judgment unit 7 generates a signal to turn off the generation of the laser beam (or the signal to turn on the generation of the laser beam stops). ), the LD drive signal of the driver 9 stops. Therefore, emission of laser light is stopped, and destruction of recorded data is prevented.

[0023] In this way, the recorded data is not destroyed by mistake when adjusting the light beam output, so the adjustment of the light beam output can be performed reliably, and the recorded data can be stably written, read, and erased. be able to.

The holding mechanism 12 in the above embodiments may be of a servo type using a sensor instead of a mechanical one. Further, this holding mechanism does not need to be dedicated to adjusting the light beam intensity, and can also be used as a holding (locking) mechanism for when the power is turned off. Further, the locking mechanism may be a brake mechanism that presses flat surfaces with a large friction coefficient together, instead of using the comb-like notched grooves. The light beam detector 3c does not have to be built into the optical head 3, but may be externally attached.

[0025]

As described in detail above, the present invention provides an optical disc device that can reliably adjust the light beam output and stably write, read, and erase recorded data. can.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram showing the configuration of an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing the track arrangement of an optical disc.

FIG. 3 is a configuration diagram showing the configuration of main parts of an apparatus according to an embodiment of the present invention.

[Explanation of symbols]

Claims (2)

[Claims] [Claim 1] An optical disk device that is equipped with an optical head that focuses a light beam onto an optical disk and that reads and writes information on the optical disk, wherein the optical head is held on the inner or outer side of recordable tracks on the optical disk. the optical head; a light output detection means for detecting the light output of the light beam emitted from the optical head; and a light beam output control means for controlling the light beam output based on the detection result of the light output detection means. An optical disc device characterized by: 2. Comparison and determination means for comparing and determining the detection result of the light output detection means and a predetermined set value, and control means for stopping the light beam output based on the determination result of the comparison and determination means. The optical disc device according to claim 1, characterized in that: