JP2583640B2 - Optical disk drive - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disk device, and more particularly, to an optical disk device capable of recording / reproducing information.

[Prior Art] An optical disk has characteristics of high density and large capacity as compared with a magnetic disk, and is widely used as a recording medium for code information and image information.

By the way, even in the case of an optical disc, there is a copy process of copying the recorded information to another optical disc in order to back up the recorded information. This copy process is performed by using two optical disk devices, reproducing the copy source optical disk with one copy source device, and recording the other one as a copy destination device on a new copy destination optical disk. I have.

[Problems to be Solved by the Invention] The above-mentioned conventional technology does not consider reduction of processing time at the time of copying.

That is, since the copy handles a much larger amount of data than the data amount handled in the normal access, the copy time is governed by the amount of data to be copied and the processing speed of both. The conventional copy processing is basically performed by reading data from a copy source device and writing the data to a copy destination device. Therefore, the conventional copy process has a problem that if there is a large amount of copy data, it takes a long time to copy.

In particular, in an optical disk device, since it takes time to write data, it largely depends on the processing speed on the writing side. For example, when performing a full copy of a 12 "(30 cm diameter) optical disk, there is a problem that a large amount of time is required for processing, for example, it takes 24 hours at worst.

The cause is considered as follows. For example, in the case of an optical disk, when writing, it is necessary to irradiate the power of the light source of the write head to the recording surface with an optimum energy density due to characteristics such as heat capacity on the recording surface of the disk. For this reason, when the rotation speed of the optical disk is increased in order to increase the recording speed, the energy density of the light source power applied to the recording surface of the optical disk decreases, and the recording on the recording surface cannot be performed sufficiently. Likely to occur. Therefore, the data must be written at a normal recording speed, and the copying process takes a long time.

Incidentally, as a method of increasing the power of the light source, it is conceivable to increase the drive current of the semiconductor laser. However, in this method, the semiconductor is greatly consumed, and the life is significantly shortened. In this case, it is conceivable to replace the semiconductor, but it is not easy to perform optical adjustment such as optical axis alignment with the optical system of the head, and eventually it is necessary to replace the expensive head itself, which is uneconomical. There is a problem that there is.

On the other hand, as a method for improving the recording characteristics of the optical recording medium as described above, Applied Physics Letter (Appl. Phys. Lett. 39 (8), 15 (October 1)
981.pp.583-585), a recording spot with a large diameter by a semiconductor laser beam and a pre-heating spot with a small diameter by a He-Cd laser are condensed by the same lens. Then, there is a method of recording information.

However, this conventional technique for improving recording characteristics uses a He-Cd laser separately from a semiconductor laser, so that there is a problem in terms of downsizing of the device due to an increase in the size of the device, and also a problem in handling. There is no practical. Therefore, this method is difficult to adopt.

SUMMARY OF THE INVENTION An object of the present invention is to provide an optical disk apparatus that can rotate an optical disk in at least two modes, low speed and high speed, at the time of recording / reproducing, and can prolong the life of laser beam generating means. .

[Means for Solving the Problems] To achieve the above object, according to the present invention, in an optical disk device for optically recording / reproducing information on an optical disk, a low-speed and a high-speed At least 2
A disk rotation drive unit for rotating the optical disk at a rotation speed of a certain mode; and a first laser beam generation unit and a second laser beam generation unit for irradiating the optical disk with a light beam, respectively. The first laser beam generating means and the second laser beam generating means bear the generation of the main beam alternately. In the high-speed mode, the laser beam generating means which does not bear the generation of the main beam is An optical disk device is provided, which bears the occurrence of the optical disk.

According to the present invention, the first laser beam generating means and the second laser beam generating means further include a counter for measuring a use time of the laser beam generating means when they bear the generation of the main beam. be able to. In this case, the first laser beam generating means and the second laser beam generating means can be configured such that the respective burdens are changed according to the counting result of the counter.

According to the present invention, a recording / reproducing mode and a copy mode are provided in an information recording / reproducing apparatus for recording and reproducing information by relatively moving a recording medium and a recording / reproducing head. A function of making the relative movement speed between the recording medium and the recording / reproducing head larger than that in the recording / reproducing mode can be provided. In particular, in a disk type recording / reproducing device, the rotation speed of the copy source device and the copy destination device can be made higher than the rotation speed during normal recording / reproduction.

Also, the present invention provides an information recording / reproducing apparatus for recording and reproducing information on a disk-type recording medium, wherein when copying information from a copy source apparatus to a copy destination apparatus, the copy source recording medium is: The information is reproduced by rotating at a normal rotation speed or higher, and the recording medium at the copy destination is rotated at a rotation speed at or higher than the normal rotation speed to reproduce the information from the recording medium at the copy source. It can be used for realizing an information copy method for writing the obtained information.

According to the present invention, when information is copied from a copy source optical disk to a copy destination optical disk, the information is reproduced with the copy destination optical disk having a rotation speed equal to or higher than a normal rotation speed. With the number of rotations higher than the number of rotations, on the DC power component that is superimposed during normal recording, DC power component that makes the DC power component larger power during copying, is superimposed,
The information to be supplied to the optical head and reproduced from the copy source optical disk device can be written.

Further, according to the present invention, when information is copied from a copy source optical disc to a copy destination optical disc, the information is reproduced by setting the copy source optical disc to a rotational speed equal to or higher than a normal rotational speed, and the copy destination optical disc is normally reproduced. The number of rotations is equal to or higher than the number of rotations, and at the same time, the auxiliary beam is superimposed on the light beam irradiated at the time of normal recording, so that the information reproduced from the copy source optical disk can be written.

As one aspect of the present invention, for example, a disk rotation driving means for rotating an optical disk at a rotation speed of at least two modes selected from a low speed mode and a high speed mode at the time of recording / reproducing; There is provided an optical disk device including: a light amount increasing unit configured to increase an irradiation light amount to an optical disk to which information is to be written in a mode, in comparison with an irradiation light amount in a low speed mode.

As the light amount increasing unit, for example, a unit having a function of increasing the drive current of the preheating unit that emits light from the light source for preheating compared to the time of normal writing can be used. Further, a device having a function of generating an auxiliary beam can also be used.

Further, according to the present invention, recording / reproduction of information is performed using the first optical disk device, and all or a part of the information recorded on the first optical disk is copied using the second optical disk device. File device that can be used.

Further, according to the present invention, in the optical disk device, the power of the light source for writing is set to be larger than that in normal recording only at the time of copying information.

As one embodiment, for example, for preheating (Pre-heati
ng), there is a method of improving recording sensitivity by superimposing a DC light larger than a DC light superimposed during recording to obtain a preheating effect.

In another embodiment, a pre-heating light source having a wavelength longer than the recording laser wavelength is used, and the recording light is condensed by the same lens to obtain a preheating effect, thereby improving recording sensitivity. There is something to plan.

Further, as a more specific embodiment, for preheating (Pre-hea
ting) Improve the recording sensitivity by irradiating or superimposing the spot only at the time of copying, and by setting the number of rotations of the optical disk device for copying to be higher than the number of rotations at the time of normal recording and reproduction, the Some of them are shortened.

[Operation] The present invention provides an information recording / reproducing apparatus with a recording / reproducing mode and a copy mode, wherein the relative movement speed between the recording medium and the recording / reproducing head is set in the recording / reproducing mode. It has a function to increase the speed. For this reason, conventionally, the normal reproduction speed and the writing speed of the copy source device and the copy destination device have been dominated, but in the present invention, the recording medium and the recording / recording speed are different from the normal reproduction speed and the writing speed. High-speed copying can be performed by moving the reproducing head relatively. Therefore, even if there is a large amount of copy data, the copy time can be shortened.

Further, in the case of an optical disk, recording sensitivity is improved by irradiating or superimposing light for preheating only at the time of copying. Accordingly, even when the optical disk is rotated at a high speed, the energy density of the light power applied to the recording surface does not decrease, and writing to the recording surface can be performed reliably. Accordingly, the recording / reproducing time can be reduced by setting the rotation speed of the optical disk higher than the normal rotation speed.

In addition, the power of the light source is not increased by the writing power itself of the semiconductor laser, but is merely preheated only at the time of copying, so that the life of the semiconductor laser can be prevented from being shortened. In addition, when the auxiliary preheating light source is used, the semiconductor laser is not particularly burdened with power, so that there is no problem about the life.

As described above, according to the present invention, since the recording sensitivity can be improved by using the laser light source or the auxiliary preheating light source, the copy time can be reduced by using the same semiconductor laser as in the related art.

Examples Examples of the present invention will be described below with reference to the drawings.

A first embodiment of the present invention will be described with reference to FIG.

This embodiment uses a write-once optical disc to record / reproduce information optically in an optical disc apparatus.
A disk rotation driving means for rotating the optical disk at a rotation speed selected from at least two modes of low speed and high speed during reproduction; and irradiating the optical disk to which information is to be written when the rotation speed of the optical disk is a high speed mode. An example of an optical disk device including a light amount increasing unit for increasing the light amount more than the irradiation light amount in the low speed mode will be described. In this case, the information recording function and the information reproducing function are one in one.
Although an example of the device provided on the table is shown, a configuration in which the recording function and the reproducing function are performed by different devices may be adopted.

In the present embodiment, the optical disc 9, a motor 18 for rotating the optical disc 9, a motor drive control circuit 15 that functions as a disc rotation drive unit in the present embodiment, controls the drive of the motor 18, and functions as a light amount increasing unit An optical head 1 for writing and reproducing information on and from the optical disk 9, a laser drive circuit 16 for driving the semiconductor laser 2 in the optical head 1, and a signal detected by the optical head 1. Information reproduction circuit 12 that reproduces information from
A servo circuit 11 and an actuator drive circuit 13 for driving various actuators such as a voice coil of the optical head 1 using a detection signal of the optical head 1, and a controller 17 for controlling the entire apparatus. Is done.

As a recording film on the write-once optical disc 9, an amorphous film such as PbTeSe is formed by vapor deposition or sputtering.

An optical head 1 includes a semiconductor laser 2 and the semiconductor laser 2.
A coupling lens 3 for converting light from the light into parallel light, a deflecting prism 4, a λ / 4 wavelength plate 5, a galvanomirror 6,
It comprises a condenser lens 8, a voice coil 7 for driving the condenser lens 8, and a photodetector 10.

In the optical head 1 shown in FIG. 1, light emitted from the semiconductor laser 2 is converted into parallel light by the coupling lens 3,
The light is incident on the optical disk by the polarizing prism 4, the λ / 4 plate 5, the galvanometer mirror 6, and the condenser lens 8 attached to the voice coil 7. The light reflected by the optical disk passes through the condenser lens 8 again, is reflected by the λ / 4 plate 5 and the polarizing prism 4, and is guided to the detection optical system. The detection optical system is composed of an optical system of an automatic focus (AF) signal detection system, a tracking (TR) signal detection system, and a reading signal detection system, which will be described in detail in the second embodiment. Here, the photodetector 10 is only illustrated.

The auto-focus (AF) signal detected by the photodetector 10 becomes a differential signal obtained by taking a difference in the servo circuit 11, is phase-compensated, and is input to the actuator drive circuit 13. The voice coil 7 is finely moved by the AF drive signal obtained from the actuator drive circuit 13, and the spot narrowed down by the condenser lens 8 is maintained at about 1 μmφ by following the vertical swing of the optical disk rotating at a constant speed by the motor 18.

Also, a track tracking (TR) signal from the photodetector 10 is
Similarly to the AF signal, the differential signal is obtained as a differential signal in the servo circuit 11 and then phase-compensated and input to the actuator drive circuit 13. According to the TR drive signal obtained from the actuator drive circuit 13, the galvanometer mirror 6 is rotated,
Information is reproduced by following the eccentricity of a guide groove (not shown) recorded on the optical disk in advance.

Further, the read signal detected by the photodetector 10 is led to the information reproducing circuit 12, where the information is read, and led to the controller 17.

Information is recorded by inputting recording data from a controller 17 to a laser drive circuit 16, causing the semiconductor laser 2 to oscillate at a high output pulse, thermally opening a recording film (not shown) on an optical disk, and forming a pit. Is formed.

FIG. 2A shows the output waveform of the semiconductor laser in the recording mode. The output waveform is usually a waveform in which a pulse component is superimposed on a DC power component equal to the reproduction power RD, and the peak of the pulse is the recording power WR.

As described above, an optical disc may perform a copy operation for backing up recorded information, similarly to other information media. However, in the case of an optical disk, there is a time when the recording time is too long because the recording capacity is larger than other information media and the recording speed is slow. Therefore, in the present embodiment, at the time of copying, the DC power component as shown in FIG. 2 (2) is set as the copy power CP having a value larger than the reproduction power RD, and the recording power WR 'is different from the recording mode.

The copy time is shortened by setting the rotation speed of the motor 18 to twice or more the speed at the time of recording and setting the recording speed to twice or more. Specifically, when copying information, the copy source optical disk device reproduces the information at twice or more the number of rotations, and in synchronization therewith, the copy destination optical disk device also rotates at the same number of rotations. Next, the information copy reproduced by the copy source optical disk device is sent to the destination optical disk device. Based on this information, the copy destination optical disk device records the information at a recording speed that is at least twice the normal recording mode.

Hereinafter, the recording characteristics at the time of copying will be described in more detail.

FIG. 3 shows calculation results of recording characteristics when a PbTeSe film is used as the recording film. The horizontal axis is the recording power, and the vertical axis is the pit length recorded on the recording film. The DC power component Pdc superimposed on the recording power and the linear velocity are represented as parameters.

The pit length is calculated by assuming a laser wavelength of 0.78 μm, a numerical aperture (NA) of the condenser lens of 0.55, and a spot distribution as a Gaussian distribution. It is calculated from the melting region in the traveling direction exceeding the melting temperature of the film.

Linear velocity 10m / sec, disc diameter 30cm, rotation speed 60r.pm
Corresponds to the linear velocity at the outermost circumference when rotating at a constant speed, and a linear velocity of 20 m / sec corresponds to a rotational speed of 1200 rpm. For example, at the time of recording, the recording power is 6 mW, the DC component is 1 mW, and the recording pulse width is 200 nse.
If normal recording is realized in c, the condition for recording information by doubling the rotation speed during copying, that is, doubling the linear velocity is as shown in FIG. 3 from the recording power of 7 mW and the DC component. Three
With mW and a recording pulse width of 100 nec, the same pit length can be spatially recorded on the disk, and high-speed recording can be realized.

If the DC component is set to 1 mW, which is the same as during recording, and the rotation speed and the recording speed are doubled, the recording power is proportional to the rotation speed and the square root of the pulse width under adiabatic conditions. 12 mW is required, and the life of the laser used becomes a problem.

However, according to the present invention, there is no problem in terms of the life of the laser, because only the recording power is increased by 1 mW with respect to the normal recording, and the recording power is increased only at the time of copying.

The laser drive circuit 16 for realizing the laser output waveform in the recording mode and the copy mode as shown in FIG. 2 will be described in detail with reference to FIGS. 4, 5 and 6. The laser drive circuit 16 includes a function as a light amount increasing unit.

The laser drive circuit 16 shown in FIG. 4 includes a reproduction power control (RD APC) circuit 161 for keeping the reproduction power RD shown in FIG. 2 constant and a pulse current for driving the laser corresponding to the recorded information. Recording pulse drive for reproduction (WR PL
S) circuit 162. The recording pulse drive circuit 162 includes
Laser diode 21 constituting light emitting portion of semiconductor laser 2
a is connected, and the reproduction power control circuit 161 is connected to a monitor 21b for detecting the output of the laser diode 21a.

The reproduction power control (RD APC) circuit 161 includes a monitor (MONI) disposed behind the laser diode (LD) 21.
TOR) 21b detects a laser output component proportional to the output power of the laser diode 21a, and drives the laser so that the monitor output is constant. At the time of normal recording / reproduction, the reproduction power RD of the DC component is set by a recording / copy (WRITE / COPY) command, and at the time of copying, the DC level is set at the copy power CP. The recording pulse drive (WR PLS) circuit 162 generates a pulse current for driving the laser diode 21a according to the recording information. In this case, the DC level RD set by the playback power control (RD APC) circuit 161
The pulse component is superimposed on the CP, and the peak value is the recording power W
Set to R, WR '.

FIG. 5 shows the details of the reproduction power control circuit 161.

In the figure, a monitor current flowing in proportion to the amount of light received by the monitor 21b is converted into a voltage by a resistor R1 and further multiplied by (1 + R3 / R2) by an operational amplifier OP1. The output of the operational amplifier OP1 is input to the analog switch ASW. The analog switch ASW receives a control signal W indicating that recording is in progress.
It is turned ON / OFF by R and GATE-P. In the playback mode, the control signal WR GATE-P becomes “L” and the analog switch ASW
Is turned ON, and the power control function operates.
In the recording / copy mode, the control signal WRGATE-P is set to “H”.
As a result, the analog switch ASW is turned off, and the output level at the time of reproduction is held by the capacitor C1, thereby preventing fluctuation of the RD / CP power due to the recording pulse.

The output of the analog switch ASW is input to the operational amplifier OP3 after passing through the voltage follower of the operational amplifier OP2. The operational amplifier OP3 converts the input signal to the reference voltage −V2
This is an amplifier that amplifies by -R5 / R4 times with reference to and has a time constant of R5 × C2. This output is connected to resistor R7, transistor TR
1 and TR2 are input to an operational amplifier OP4 constituting a current source. The potential at the point (A) at this time is almost the output of the operational amplifier OP3.

The output from the D / A converter 164 is input to the operational amplifier OP5 which forms a current source together with the resistor R9 and the transistor TR3. In the reproduction / recording mode, DATA for sending a current corresponding to the DC power RD is sent from the controller 17, and a latch (LATCH) 163 outputs D in response to the control signal WR / COPY.
After determining the ATA, it is input to the D / A converter 164. Similarly, in the copy mode, the DC copy power
DATA for sending a current corresponding to CP is transmitted. Since the potential at the point (B) of the current source formed by the operational amplifier OP5 is equal to the output from the D / A converter 164, the current DC flowing to emit the DC reproduction power RD or the copy power CP is (A It is equal to the potential difference between points) and (B) divided by the resistance R8.

As described above, the DC drive current can be changed by the instruction DATA from the controller.

FIG. 6 shows the details of the recording pulse drive (WR PLS) circuit 162.

In FIG. 6, a write data (WR DATA) pulse from the controller 17 is an ECL (Emitter Coupled Log).
ic) through IC1 and IC2, and is biased at −V4 through resistors R18 and R19, and then through transistors R4 and T3 through resistors R12 and R13.
It is input to the current switch circuit 165 composed of R5. If the WR DATA pulse is “H”, TR4 turns on and TR5
Is turned off, so that no pulse current (PLS) flows through the laser diode 21a. Next, if the WR DATA pulse is in the "L" state, TR4 is turned off and TR5 is turned on, so that a pulse current (PLS) flows through the laser diode 21a. Therefore, the laser diode 21a
From the playback power control (RD APC) circuit 161
It is driven by a current obtained by superimposing a DC current (CD) and a pulse current (PLS) at a point (C).

The peak value of the pulse current (PLS) is determined by the value of the D / A converter 167 input to the operational amplifier OP6 constituting a current source together with the transistor TR7. The D / A converter 167 receives the WR CRNT DATA corresponding to the recording current from the controller 17 by the latch circuit 165 and inputs the value determined by the control signal WR / COPY to DATA. Therefore, in response to the instruction DATA from the host controller, the pulse current (PL
The peak value of S) can be changed.

With reference to FIG. 9, a description will be given of a motor drive control circuit in a case where the motor rotation speed of the optical disk device is changed.

Motor rotation control is performed by a rotation detector attached to the motor 18.
181 generates a rotation pulse, and compares the rotation pulse with a reference pulse from the crystal oscillator 151 by using a PLL (PH
(ASE LOCKED LOOP) method is used.

The rotation pulse from the rotation detector 181 is supplied to an FV conversion circuit 155 and an LPF (low-pass filter) circuit 15 as a speed control system.
6 and a phase control system including a frequency dividing circuit 152 and a phase comparing circuit 154. The speed control voltage from the LPF circuit 156 at the subsequent stage of the FV (frequency-voltage) conversion circuit 155 is input to the addition circuit 154. Further, in the phase control system, the pulse obtained by dividing the rotation pulse by the frequency dividing circuit 153 is compared with the reference pulse divided by the dividing speed switching circuit 152 which is selected according to the output pulse rotation speed from the crystal oscillator 151, The phase is compared by the adder 154 and becomes a phase control voltage, which is input to the adding circuit 154. The output of the addition circuit 154, which has added the speed control voltage and the phase control voltage, is amplified by a DC amplifier 158 having a loop filter characteristic, and then the motor 18 is maintained at a constant rotation by a motor drive circuit 159.

When the rotation speed is changed, the frequency division ratio is switched by the RD / WR / COPY signal in the division speed switching circuit 152 to respond to the frequency change of the rotation pulse. It can be realized by switching in accordance with.

Next, a second embodiment for realizing the same effects as the recording mode and the copy mode shown in FIG. 2 will be described with reference to FIG.

In the first embodiment, the number of rotations and the recording speed are doubled in the copy mode, and the function of the light amount increasing means is as follows.
Although the method of setting the DC power to be superimposed on the recording pulse to be twice or more has been described, in the second embodiment, the preheating effect is given.
Instead of increasing the DC power, another light source, for example, a light emitting diode is used, and the main spot by the laser and the sub spot by the light emitting diode are illuminated on the same track through a common condenser lens to obtain the same effect. Things.

This embodiment is configured similarly to the above-described first embodiment except that an auxiliary beam is used. That is, an optical disk 29 rotated and driven by a motor (not shown), an information reproducing circuit 38, a servo circuit 36 and an actuator driving circuit 37, a laser driving circuit 39, the optical head 20,
It comprises a D drive circuit 43 and a controller 44.

The optical head 20 includes a semiconductor laser 21 and the semiconductor laser.
A coupling lens 22 that converts light from 21 into parallel light, a polarizing prism 23, a λ / 4 wavelength plate 24, a dichroic mirror 25, a galvano mirror 26, a condenser lens 28, and the condenser lens 28. It comprises a voice coil 27 to be driven and a light detection system 30.

The light detection system 30 has a lens 32, a half prism 33, and light detectors 34 and 35. The photo detectors 34 and 35 are
As shown in FIG. 7 (b), it is composed of four divided photodetectors, and the former is disposed before the focal point and the latter is disposed behind the focal position of the lens 32. .

In such a configuration, the light emitted from the laser 21 becomes parallel light by the coupling lens 22 and enters the polarizing prism 23. The light emitted from the polarizing prism 23 is λ / 4
The light passes through a dichroic mirror 25 having a feature of transmitting the wavelength of the plate 24 and the laser 21, and is narrowed down as a spot 30 of about 1 μm on a write-once optical disc 29 by a galvanometer mirror 26 and a condenser lens 28 attached to a voice coil 27. It is irradiated. The light reflected by the write-once optical disc 29 passes again through the condenser lens 28, the galvanometer mirror 26, the dichroic mirror 25, and the λ / 4 plate 24, is separated in the optical path by the polarizing prism 23, and enters the lens 32. I do. The light emitted from the lens 32 is incident on the half prism 33, is divided into two light amounts, and is incident on the photodetectors 34 and 35.

In each of the photodetectors 34 and 35, photodetectors A1 and A
After adding the two outputs, the servo circuit 36 differentiates the two added outputs to obtain an automatic focus detection signal. Also, the photodetectors T1 and T2 are
It is arranged so as to receive the diffracted light from the guide groove recorded in advance on 29. Then, after adding the outputs of the respective photodetectors T1 and T1, and the outputs of T2 and T2, the servo circuit
By differentiating the two summed outputs at 36, a track tracking signal can be obtained. Further, the detection of the information signal recorded on the write-once optical disc 29 is performed by adding the outputs of all the photodetectors of each photodetector.

The automatic focus detection signal and the track tracking signal obtained by the servo circuit 36 are input to the actuator drive circuit 37.
The actuator drive circuit 37 drives the voice coil 27 and the galvanomirror 26 based on this signal, and the spot thus narrowed down is written on the write-once optical disc.
Follow 29 vertical swing and track eccentricity.

In the recording mode, the laser 21 is
This can be realized by pulse driving by the laser driving circuit 39 according to WR DATA.

In the copy mode, the laser 21 is pulse-driven in the same manner as in the recording mode.
To emit light. The light emitted from the light emitting diode 42 is
The light 41 becomes almost parallel light and enters the dichroic mirror 25. The wavelengths of the laser 21 and the light emitting diode 42 are different. The dichroic mirror 25 is, as described above,
It has the characteristic of transmitting at the laser wavelength and reflecting at the wavelength of the light emitting diode. The light reflected by the dichroic mirror 25 is narrowed down as a spot 31 on an optical disc 29 through a galvano mirror 26 and a condenser lens 28, similarly to the laser light.

The wavelength of the light emitting diode 42 is selected to be longer than the wavelength of the laser 21.

The spot 31 narrowed down by the light emitting diode 42 is narrowed down by the laser due to poor wavelength and poor coherence.
In order to realize the pulse waveform shown in FIG. 2, it is necessary to optimize the driving conditions of the light emitting diode.

In the second embodiment, a light emitting diode is required in addition to the laser as the main light source, but there is no problem about the life of the laser.

In this embodiment, a light emitting diode is used as a means for generating the auxiliary beam, but the present invention is not limited to this. Further, the relationship between the wavelengths is not limited. For example, an auxiliary beam may be generated by a laser diode.

In addition, a laser diode that generates an auxiliary beam is
It may be the same as that which generates the main beam. In this case, the generation of the main beam and the generation of the auxiliary beam may be alternated without changing their positions. As a result, it is possible to prevent only one laser diode from being consumed, and it is possible to extend the life apparently. Further, in this case, it is preferable that the usage time as the main beam is counted by a counter or the like and the usage time is averaged, because the life of the optical head can be more efficiently extended.

FIG. 8 shows an embodiment in which a copy operation is performed. The optical disk devices capable of postponing high-speed copying include a copy source optical disk device 101 and a copy destination optical disk device 102.
And the host controller 103 via data buses 104 and 106 and instruction buses 105 and 107.

In the copy mode, the upper controller 103 issues a copy command to both optical disc devices via the command buses 105 and 107, and sets the disc rotation speed to a normal rotation speed or more, for example,
The frequency is increased by a factor of two, and the clock for recording and reproduction is also doubled accordingly. Then, the upper controller 10
3 instructs the destination optical disk device 101 and the destination optical disk device 102 of the destination address to start copying. Accordingly, in both optical disk devices, the optical head is
Move to the destination address and start reproducing and copying information.

The information reproduced by the copy source optical disk device 101 is demodulated by the controller 171 in the copy source optical disk device 101, and then sent out to the host controller 103 via the data bus 104.
Is stored in When the reproduction is continued and the buffer memory 108 is full, next, another buffer memory 109 in the host controller 103 is switched to continue the storage. At the time when the buffer memory 108 becomes full, the transmission of the data reproduced by the copy source optical disc device 101 from the buffer memory 108 to the copy destination optical disc device 102 via the data bus 106 is started, and the transmission to the copy destination optical disc device 102 is started. Start copying.

In the copy destination optical disk device 102, after the data is modulated by the controller 172, the data is recorded by the laser waveform shown in FIG. 2 (2).

When the buffer memory 109 is full, the buffer memory 108
When the copy to the copy destination optical disk device 102 is completed, the data reproduced by the copy source optical disk device 101 is again stored in the buffer memory 108, and the data stored in the buffer memory 109 is copied. The copy is sent to the destination optical disk device 102 and copying is continued.

By continuing the above operation until the copy mode ends, the copy time can be reduced to half or less as compared with the conventional case where copying is performed at a normal rotation speed.

In the above-described embodiment, two optical disc apparatuses each having a high-speed recording / reproducing function together with normal recording / reproducing are used.
Copy source optical disk device 101 and copy destination optical disk device 1
02. According to such a configuration, for example, the first
The optical disk device 101 can record / reproduce information, and the second optical disk device can be used as a file device capable of copying all or a part of the information recorded on the first optical disk.

Note that the file device is not limited to such a configuration, and various combinations are possible. For example, a first optical disc apparatus in which a normal recording / reproducing function is added with at least a high-speed reproducing function capable of reproducing at a higher speed than the normal recording / reproducing function, At least one high-speed recording function capable of high-speed recording,
A file device provided with a base, capable of recording / reproducing information using a first optical disk device, and copying all or a part of information recorded on a first optical disk using a second optical disk device Is obtained.

As described above, the write-once optical disk has been described as an optical disk, but it goes without saying that the same effect can be obtained with other optical disks such as a rewritable magneto-optical disk and a phase-change optical disk.

According to the various embodiments of the present invention described above, the DC component to be superimposed on the recording power only at the time of copying information is set to be twice or more the DC component at the time of normal recording, or By using a long preheating light source and condensing the light with the same lens as the laser, the recording sensitivity can be improved. Therefore, the number of rotations of the disk and the recording speed are set to 2
By making it twice or more, the copy time can be shortened.

In addition, since the semiconductor laser is not driven at high power but is driven at high power by preheating driving, the life of the semiconductor laser constituting the main beam can be prevented from being shortened. Further, by using a plurality of semiconductor lasers alternately for the main beam and the auxiliary beam, the apparent life can be extended.

In each of the embodiments described above, the use in the recording / reproduction mode and the copy mode is described. However, the optical disk device of the present invention enables a high-speed access mode and a low-speed access mode from a host computer. .
That is, if it is necessary to read and write data in a short time, select the high-speed mode (copy mode). If not, select the low-speed mode (normal recording / playback mode). Recording / reproduction of information can be performed.

[Effects of the Invention] According to the present invention, the copy source device and the copy destination device are not governed by the normal reproduction speed and write speed,
High-speed copying can be performed, and the copying time can be reduced.

[Brief description of the drawings]

FIG. 1 is a block diagram showing the overall configuration of the embodiment of FIG. 1 of the present invention, FIG. 2 is a waveform diagram showing optical output waveforms in a recording mode and a copy mode in the first embodiment, and FIG. Is a graph showing recording characteristics (calculated results) of the PbTeSe recording film,
FIG. 4 is a block diagram showing an example of a configuration of a laser driving circuit, FIG. 5 is a circuit diagram showing a detailed configuration of an RDAPC circuit,
FIG. 6 is a circuit diagram showing a detailed configuration of the WR PLS circuit, and FIG.
7A is a block diagram showing the overall configuration of a second embodiment of the present invention, FIG. 7B is a plan view showing an example of the element arrangement of the photodetector, and FIG. 8 is an embodiment at the time of copying. FIG. 9 is a block diagram showing an example of the configuration of a motor drive control circuit publicly used in each embodiment of the present invention. 1 Optical head, 2,21 Semiconductor laser, 3,22 Coupling lens, 4,23 Polarizing prism, 5,24 λ
/ 4 plate, 6,26… galvanometer mirror, 7,27… voice coil, 8,28… condenser lens, 9,29… write-once optical disc,
10,34,35 …… photodetector, 11,36 …… servo circuit, 12,38…
… Information reproduction circuit, 13,37 …… Actuator drive circuit, 1
5 ... Motor drive control circuit, 16,39 ... Laser drive circuit,
17,44 …… Controller, 18 …… Motor, 161 …… RD AP
C circuit, 162 WR PLS circuit, 101 Copy source optical disk device, 102 Copy destination optical disk device, 103 Host controller, 104, 106 Data bus, 105, 107 Command bus, 108, 109 Buffer memory, 171,172 ... Controller.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Jin Komatsu 2880 Kozu, Kozuhara, Odawara City, Kanagawa Prefecture Inside the Odawara Plant, Hitachi, Ltd. 72) Inventor Tetsuya Nishida 1-280 Higashi Koikekubo, Kokubunji-shi, Tokyo Inside the Hitachi, Ltd. Central Research Laboratory (72) Inventor Masahiro Ojima 1-280 Higashi Koikekubo, Kokubunji-shi, Tokyo Inside the Hitachi Research Center Central (72) Seiji Honda, 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Prefecture Inside Microelectronics Device Development Laboratory, Hitachi, Ltd. (72) Inventor Masamichi Ito 502, Kandatecho, Tsuchiura-shi, Ibaraki Prefecture Machinery Laboratory, Hitachi, Ltd. (72) Inventor Kunihiko Kizaki Hata, Kanagawa Prefecture No. 1 Horiyamashita, No. 1 Kanagawa Plant, Hitachi, Ltd. (56) References JP-A-63-102054 (JP, A) JP-A-2-83856 (JP, A) JP-A-53-50707 (JP, A)

Claims (2)

(57) [Claims] 1. An optical disk device for optically recording / reproducing information on an optical disk, wherein a disk rotation drive means for rotating the optical disk at a low speed and a high speed of at least two kinds of modes when recording / reproducing information. And a first laser beam generating means and a second laser beam generating means for irradiating the optical disc with a light beam, respectively, the first laser beam generating means and the second laser beam generating means, An optical disc apparatus characterized in that, in the high-speed mode, a laser beam generating means that does not bear the generation of the main beam bears the generation of the sub-beam alternately. 2. The apparatus according to claim 1, wherein the first laser beam generating means and the second laser beam generating means use the laser beam generating means when they bear generation of a main beam. An optical disc device, further comprising a counter for measuring, wherein the first laser beam generating means and the second laser beam generating means change their respective loads according to the counting result of the counter.