JPH0714192A - Optical pickup drive control device - Google Patents

Abstract

PURPOSE:To control the drive of an optical pickup without depending on an environmental temp. CONSTITUTION:An ambient temp. of the optical pickup 10 is detected by a temp. sensor 31. A constant of the drive control of the optical pickup 10 is variably adjusted by electronic volumes 35 and 36. The electronic volumes 35 and 36 are controlled by a microcomputer 32 in accordance with temp. information detected by the temp. sensor 31, so that variable adjustment corresponding to a temp. change can be carried out.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical pickup drive control device for controlling the drive of an optical pickup used for recording and / or reproducing information signals on an optical recording medium such as an optical disk.

[0002]

2. Description of the Related Art An optical disk apparatus focuses a beam spot from a laser light source on a target track on a signal recording surface of an optical disk, which is an optical recording medium, through an optical device and an objective lens, and at the same time, targets the signal recording surface. The light beam reflected from the surface of the track is detected by a photodetector to record and / or reproduce information. At this time, the biaxial device is controlled by being displaced in the biaxial directions of the optical axis direction (that is, the focus direction) and the direction orthogonal to the optical axis (that is, the tracking direction).

The focus direction drive control circuit of the biaxial device, that is, the focus servo control circuit, drives the biaxial device based on the output signal of the photodetector in order to focus the beam spot on the signal recording surface. The objective lens is driven by drive control.

Further, the tracking direction drive control circuit of the biaxial device, that is, the tracking servo control circuit, uses the output signal of the photodetector in order to move and follow the beam spot to the target track on the signal recording surface. Based on this, the biaxial device is drive-controlled to drive the objective lens.

In order to stabilize the servo control, the focus servo control circuit and the tracking servo control circuit perform offset adjustment of the output from the optical pickup, loop gain adjustment of the servo loop, etc. to drive the biaxial device. To control.

This is because the amount of displacement of the biaxial device in the optical axis direction and in the direction orthogonal to the optical axis is not constant in each device. This is caused mainly by variations in the characteristics of each component constituting the biaxial device, variations in assembly, etc., and variations in sensitivity when converting the input voltage and input current supplied as drive signals into mechanical drive displacement. This is because it will end up.

Servo control by such a servo control circuit has been performed by using a semi-fixed resistor 102 as shown in FIG. 5 and fixing a servo constant which is a constant for drive control. That is, as shown in FIG.
The detection signal from the light receiving element of the photo detector (not shown)
The focus error signal F _E and the tracking error signal T _E , which are received by the amplifier 101 and subjected to predetermined arithmetic processing, are passed through the semi-fixed resistor 102 to be fixed constants and set as servo constants. (SS
P) 103. This servo signal generation circuit 103
Generates a focus servo signal or a tracking servo signal based on the servo constant and supplies it to the biaxial device of the optical pickup 80 via the drive amplifier 104. Then, the biaxial device drives an objective lens to adjust focus or tracking.

[0008]

By the way, when servo control is performed using this semi-fixed resistor, the adjustment value during operation becomes fixed.

However, in reality, the optical pickup is
It is affected by the ambient temperature and its characteristics may change. That is, the servo characteristics are deteriorated due to the surrounding environment temperature being high or low.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a drive control device for an optical pickup that can control the drive of the optical pickup without depending on the ambient temperature.

[0011]

In an optical pickup drive control device according to the present invention, an optical pickup detects a recording track of a disc-shaped optical recording medium on the basis of a signal obtained from reflected light from the disc-shaped optical recording medium. In an optical pickup drive control device for controlling the drive of the optical pickup so as to emit laser light, a temperature sensor for detecting the temperature in the vicinity of the optical pickup, and an electronic volume for variably adjusting the drive control constant of the optical pickup. The above problem is solved by having a control unit that controls the variable adjustment of the electronic volume according to the temperature information detected by the temperature sensor.

Here, the controller detects the amount of change in the temperature information detected by the temperature sensor by the microcomputer.

[0013]

[Operation] Since the control unit causes the electronic volume to variably adjust the drive control constant of the optical pickup according to the temperature information near the optical pickup detected by the temperature sensor, the drive of the optical pickup is controlled without depending on the ambient temperature. it can.

[0014]

Embodiments of the optical pickup drive control device according to the present invention will be described below with reference to the drawings. Figure 1
FIG. 3 is a block circuit diagram showing a schematic configuration of the present embodiment.
In this embodiment, as shown in FIG. 1, the drive of the optical pickup 10 for irradiating the recording track of the optical disc with the laser beam is controlled based on the signal obtained from the reflected light from the optical disc which is the disc-shaped optical recording medium. The servo control circuit 30.

In FIG. 1, in this embodiment, a temperature sensor 31 for detecting the temperature in the vicinity of the optical pickup 10 is used.
And electronic volumes 35 and 36 for variably adjusting drive control constants of the optical pickup 10, and a microcomputer 32 for variably adjusting the electronic volumes 35 and 36 in accordance with temperature information detected by the temperature sensor 31. And have.

The optical pickup 10 has a structure as shown in FIG. 2 and utilizes the magneto-optical effect (MO) to reproduce a signal from the magneto-optical disk 1 which is a rewritable optical disk.

In FIG. 2, emitted light from a laser light source 11 such as a laser diode (LD) is a collimator lens 12 and a polarization beam splitter (PBS) 13.
Through the objective lens 14 to enter the signal recording layer 1a of the magneto-optical disc 1. Next, the magneto-optical disk 1
The reflected light flux reflected by the signal recording layer 1 a of the above reaches the reflecting surface 13 a of the PBS 13 via the objective lens 14. The reflecting surface 13a changes the direction of the reflected light beam by 90 degrees. The reflected light beam whose direction is changed by 90 degrees is converged by the detection lens 15, passes through the 3-beam Wollaston Prism 16 and is incident on each light-receiving surface of the photodetector detector 17. Collected.

The above three-beam Wollaston prism 1
6 is a uniaxial crystal such as quartz, rutile, or calcite, and is a pair of first and second triangular prisms 16.
a and 16b are prisms in which the inclined surface portions are joined to each other to form a cube. The reflected light flux incident on the three-beam Wollaston prism 16 is
The beam is incident on the outer surface of the beam Wollaston prism 16 substantially perpendicularly and is obliquely transmitted to the joint surface 16c of the first triangular prism 16a and the second triangular prism 16b. When the reflected light flux passes through the cemented surface 16c, it is refracted in different directions depending on the polarization direction, and is a polarization component in a direction perpendicular to the crystal axis of the first triangular prism 16a on the light flux incident side. A first light flux R ₁ , a second light flux R ₂ that is a polarization component in a direction parallel to the crystal axis, and a third light flux R ₀ that is a component obtained by combining these components R ₀ Is divided into

The light beam received by each light receiving surface of the photodetector 17 is non-dependent on the surface of the signal recording layer 1a of the magneto-optical disk 1 depending on the defocus of the light beam irradiated on this surface. There are point aberrations. Therefore, in the photodetector 17, for example, if the third light flux R ₀ is received by the radially divided light receiving surface and the state of the astigmatism is detected, the signal recording layer 1a of the magneto-optical disc 1 is detected. The amount of defocus on the surface can be obtained by the amount of so-called focus error signal.

Each light receiving surface of the photodetector 17 described above is shown in FIG.
As shown in FIG. 3, the three-beam Wollaston prism 16 has a plurality of light-receiving surfaces for receiving the first, second, and third reflected light beams whose traveling directions are polarized.
In FIG. 3, four areas of the light receiving surface where the third reflected light flux R ₀ transmitted through the three-beam Wollaston prism 16 is received are designated as 17a, 17b, 17c and 17d. When the photodetection outputs outputted from the above four areas are S _a , S _b , S _c and S _d , the so-called defocus direction and amount on the surface of the signal recording layer 1a of the magneto-optical disk 1 are shown. The focus error signal F _e is the head amplifier RF incorporated in the optical pickup 10.
The amplifier 34 calculates as F _e = (S _a + S _c ) − (S _b + S _d ). The focus error signal F _e is also affected by the offset signal supplied from the D / A converter 33 described later.

Further, the light receiving surfaces 17g and 17h can obtain a tracking error signal from the difference between the received light detection outputs. When the light detection output of the light receiving surface 17g and 17h and S _g and S _h, the tracking error signal E
_{The e} is calculated by the RF amplifier 34, which is a head amplifier incorporated in the optical pickup 10, as E _e = S _g −S _h . The tracking error signal E _e is also affected by the offset signal supplied from the D / A converter 33 described later.

Also, the above-mentioned 3-beam Wollaston Pre
The first reflected light flux R that has passed through the prism 16₁Is the photodetector 1
The second reflected light is received by the light receiving surface 17e of
Bundle R ₂Is received by the light receiving surface 17f. Where the
Reflected light flux R of 1₁The light intensity of the first triangular prism
16a is a polarization component in a direction perpendicular to the crystal axis.
Ray and also the second reflected light flux R₂The light intensity of
One parallel to the crystal axis of the first triangular prism 16a
Since it corresponds to the extraordinary ray that is the polarized component of
Is it the difference between the light detection outputs output from the light receiving surfaces 17e and 17f?
Are written on the signal recording layer 1a of the magneto-optical disc 1 described above.
A read signal (MO) of the information signal obtained is obtained. This place
Also in this case, the RF amplifier 34 performs a calculation to obtain the MO signal.

In the present embodiment for controlling the drive of the optical pickup 10 configured as described above, a microcomputer (hereinafter referred to as a microcomputer) 32 receives temperature information in the vicinity of the optical pickup 10 detected by a temperature sensor 31, The microcomputer 32 uses the electronic volumes 35 and 36 to correct the servo constant which is a constant for drive control.

The microcomputer 32 can recognize the temperature near the optical pickup 10 by monitoring the temperature change of the reference voltage V _f of the transistor at the A / D input port. The microcomputer 32 also controls the D / A converter 33.

The D / A converter 33 is a microcomputer 3
2 receives the signal according to the temperature information,
P 34 is the main spot R₀Used to obtain the light intensity signal of
The FOKOFST signal, which is the offset signal
Signal to be supplied to the RF amplifier 34. Also this
Similarly, the D / A converter 33 receives the temperature from the microcomputer 33.
The signal corresponding to the information is received, and the RF amplifier 34 outputs the signal.
Focus error signal F _eUsed in obtaining
FOFST signal, which is the offset signal for
And is supplied to the RF amplifier 34. Also, this D
Similarly, the A / A converter 33 receives the temperature information from the microcomputer 33.
The RF amplifier 34 receives the signal according to
Locking error signal T_eUsed to obtain the
The TOFST signal, which is an offset signal for
Signal to be supplied to the RF amplifier 34. Furthermore, this
The D / A converter 33 of the
The RF amplifier 34 receives a signal according to the degree information,
Focus error signal F_eAutomatic gain control (A
GC) bias signal for focusing given to the circuit
The FBIAS signal is converted into an analog signal and the RF amplifier 34
Supply to.

Therefore, the RF amplifier 34 is
The FOKOFST signal adjusts the offset for the MO signal, and the FOFST signal and the FBAIAS signal adjust the offset for the focus error signal F _e , the TOFST
The offset is adjusted by the signal and the tracking error signal T _e is calculated and obtained as described above.

The detection element 47h of the photodetector 47 of the optical pickup 10 supplied to the RF amplifier 34.
The detection signal S _h detected in 1 passes through the balance adjustment volume 39 for balance adjustment with the detection signal S _g detected by the detection element 47 _g . The balance adjusting volume 39 also receives an EFBAL signal which is a balance adjusting volume signal from the microcomputer 32.

The focus error signal F _e obtained by the RF amplifier 34 in this way is supplied from the microcomputer 32 with a signal corresponding to temperature information.
Sent to 5. Here, this focus error signal F _e
Becomes a focus servo constant corrected according to the temperature information by passing through the electronic volume 35, and is supplied to the servo signal generation circuit 37.

The tracking error signal T _e obtained by the RF amplifier 34 is also sent from the microcomputer 32 to the electronic volume 35 to which a signal corresponding to the temperature information is supplied. Here, the tracking error signal T _e, by passing through the electronic volume 36, it is corrected tracking servo constant according to the temperature information is supplied to the servo signal generation circuit 37.

The servo signal generation circuit 37 generates a focus servo signal F _eo based on the focus servo constant and supplies it to the drive amplifier 38. Further, the servo signal generation circuit 37 generates a tracking servo signal T _eo based on the tracking servo constant, and the drive amplifier 38
Supply to.

The drive amplifier 38 controls the drive of the focus coil F _c provided in the biaxial device of the optical pickup 10 to move the objective lens 14 shown in FIG. Adjustment.

Further, the drive amplifier 38 controls the drive of the tracking coil T _c provided in the biaxial device of the optical pickup 10 to drive the objective lens 14 shown in FIG. 2 in a direction perpendicular to the optical axis. Move to and adjust the tracking.

As described above, in the present embodiment, the temperature sensor 31 for detecting the temperature in the vicinity of the optical pickup 10, the electronic volumes 35, 36 for variably adjusting the drive control constant of the optical pickup 10, and the temperature sensor 31. According to the temperature information detected by the electronic volume 35, 36
By including the microcomputer 32 that can change the servo parameter, the adjustment value of the servo constant can be changed according to the characteristic change of the optical pickup 10 due to the temperature, and the deterioration of the servo characteristic due to the temperature of the environment can be prevented.

Next, an application example to which the servo control circuit according to the above embodiment can be applied will be described with reference to FIG. In this application example, AD (adaptive difference) PCM audio data or a digital audio signal bit-compressed according to another format is recorded on a magneto-optical disk 42 which is a recording medium, and this recording signal is recorded by an optical pickup 43 in a predetermined recording unit. Burst reading is performed for each (for example, 32 sectors + several sectors), bit-compressed audio data is obtained via the decoder 71 for descrambling and error correction decoding, and this compressed data is stored in a RAM (random access memory) or the like. Write to memory 72
The audio signal is reproduced through the decoder 73 for reading out at a constant data rate from No. 2 and restoring (decompressing) the bit compression processing on the recording side for decoding.

The output of the optical pickup 43 is supplied to the RF amplifier circuit 45. The RF amplifier circuit 45 extracts the focus error signal and the tracking error signal from the output of the optical pickup 43 and supplies them to the servo control circuit 46 according to the embodiment of the present invention, and binarizes the reproduction signal, which will be described later. It is supplied to the reproduction system decoder 731.

The servo control circuit 46 is composed of, for example, a focus servo control circuit and a tracking servo control circuit. The focus servo control circuit controls the focus of the optical system of the optical pickup 43 so that the focus error signal becomes zero. Further, the tracking servo control circuit controls the tracking of the optical system of the optical pickup 43 so that the tracking error signal becomes zero. Here, the servo control circuit 46 controls the drive of the optical pickup 43 while considering the temperature around the optical pickup 43 and adjusting the servo constant so that the characteristics of the optical pickup 43 are not deteriorated. ing.

A key input operation section 48 and a display section 49 are connected to the system controller 47. The system controller 47 controls the recording system and the reproducing system in the operation mode designated by the operation input information from the key input operation unit 48. The system controller 47 is traced by the optical pickup 43 and the magnetic head 44 based on the address information in sector units reproduced from the recording track of the magneto-optical disk 42 by the header time, the Q data of the subcode, or the like. Manages the recording position and playback position on the recording track. Information on the recording position or the reproducing position, information on the function selected by the key operation, and the like are displayed on the display unit 49 as necessary.

Next, the recording system of this application example will be described. A microphone input signal A _INM , which is an analog audio signal, is input from the input terminal 50. The microphone input signal A _INM is amplified by the amplifier 52 and supplied to the selected terminal a of the changeover switch 53. In addition, the input terminal 51
From the line that is an analog audio signal (LINE)
The input signal A _INL is input and supplied to the selected terminal b of the changeover switch 53.

The changeover switch 53 is controlled by the system controller 47 to change over the switch piece c.
A microphone input signal A _INM or a line input signal A _INL is input to the low-pass filter (L
PF) 54 selectively supplied.

This LPF 54 has a changeover switch 53.
Limits the high-frequency component of the analog audio signal of the microphone input signal A _{IN M} or line input signal A _INL supplied from. The analog audio signal in which the high frequency component is limited is supplied to the automatic gain control (AGC) circuit 55 to adjust the gain.

One of the output signals whose gain is adjusted by the AGC circuit 55 is supplied to an analog / digital (A / D) converter 56. The other of the output signals is the selected terminal a of the changeover switch 76 surrounded by the broken line in the figure.
Is supplied to.

The A / D converter 56 quantizes the analog audio signal and converts it into a digital audio signal. This digital audio signal is so-called straight PCM data that is not subjected to compression processing, and as a specific example, the sampling frequency is 44.1 KHz, similar to the standard CD (compact disc) format (CD-DA format). And the number of quantization bits is 1
It is 6-bit PCM data. This 16-bit audio PCM data is, for example, AD (adaptive difference) PCM.
And the like to the encoder 59 for high efficiency encoding processing. The encoder 59 is also supplied with a digital audio signal (audio PCM data) via the input terminal 57 and the digital input interface circuit 58.

This encoder 59 is an audio PCM.
The data is subjected to high efficiency bit compression processing and supplied to the memory 60.

The memory 60 is a buffer for temporarily storing bit-compressed data supplied from the encoder 59, where writing and reading of data are controlled by the system controller 47, and for recording the data on a disk as needed. It is used as a memory. That is, for example, in the 1/4 bit compression mode, compressed data of a constant bit rate reduced to approximately 1/4 of the data transfer rate (bit rate) of the standard CD-DA format is continuously stored in the memory 60. Will be written. When this compressed data is recorded on the magneto-optical disc 42, it is recorded in a burst or discrete manner at the same data transfer rate under the same disc rotation speed (constant linear velocity) as the standard CD-DA format. There is. That is, the time during which a signal is actually recorded in the recording mode is about 1
/ 4, and the remaining 3/4 time is the rest time during which recording is not performed. However, on the magneto-optical disk 42, the next recording is performed following the area recorded immediately before the rest period, and continuous recording is performed on the medium surface. As a result, for example, the same recording density and storage pattern as in the standard CD-DA format are recorded.

Therefore, the compressed data is burst-read from the memory 60 at a bit rate corresponding to the data transfer rate of the standard CD-DA format.
The read compressed data is supplied to the encoder 61 for performing interleave processing, error correction coding processing, EFM modulation processing, and the like. Here, in the data string supplied from the memory 60 to the encoder 61, one cluster consisting of a predetermined sector (for example, 32 sectors) is a unit to be continuously recorded in one recording, and when this is encoded, The data amount for one cluster is added with a few sectors for cluster connection. This cluster connection sector is set longer than the interleave length in the encoder 61, so that even if interleaved, it does not affect the data of other clusters.

The encoder 61, regarding the recording data supplied from the memory 60 in bursts as described above,
Encoding processing for error correction (parity addition and interleave processing), EFM encoding processing, and the like are performed. The recording data encoded by the encoder 61 is supplied to the magnetic head drive circuit 62. The magnetic head drive circuit 62 is connected to the magnetic head 44, and drives the magnetic head 44 so as to apply the modulation magnetic field according to the recording data to the magneto-optical disk 42.

Next, the reproducing system of this application example will be described. This reproducing system is for reproducing the record data continuously recorded on the recording track of the magneto-optical disk 42 by the above-mentioned recording system, and is driven by the optical pickup 43 whose drive is controlled by the servo control circuit 46. A recording signal is read from the magneto-optical disk 42 by tracing a recording track of the magneto-optical disk 42 with a laser beam. Here, the magneto-optical disk 42 is rotationally driven at the same rotation speed (constant linear velocity) as the standard CD-DA format, and is bursty (discrete) at the same data transfer rate as the CD-DA format. The recording signal is read by
It is binarized by the RF amplifier circuit 45 and supplied to the decoder 71.

The decoder 71 corresponds to the encoder 61 in the recording system described above, and has the RF amplifier circuit 4
The reproduced output signal binarized by 5 is subjected to processing such as deinterleaving processing, decoding processing for error correction, EFM demodulation processing, and the like to convert the above-mentioned 1/4 compressed data into, for example, the standard CD-DA described above. Burst output at the same data transfer rate as the format. The reproduced data obtained by the decoder 71 is supplied to the memory 72.

In the memory 72, writing and reading of data are controlled by the system controller 47, and reproduced data which is supplied in burst from the decoder 71 at the same data transfer rate as the standard CD-DA format is written. Further, the reproduction data written in bursts is continuously read out from the memory 72 at a constant bit rate, that is, at a data transfer rate of about 1/4 of the standard CD-DA format.

Compressed data obtained as reproduced data continuously read from the memory 72 at a transfer rate (bit rate) of about 1/4 of the standard is supplied to the decoder 73. The decoder 73 corresponds to the encoder 59 of the recording system, and, for example, expands the compressed data of 1/4 by 4 times (bit expands) to 1
Play 6-bit digital audio data. The digital audio data from this decoder 73 is
It is supplied to the D / A converter 74 and is also derived from the output terminal 81 via the digital output interface circuit 80.

The D / A converter 74 converts the digital audio data supplied from the decoder 73 into an analog signal and supplies it to the selected terminal b of the changeover switch 76 via the LPF 75.

The selected audio terminal a of the changeover switch 76 is supplied with the analog audio signal whose gain is adjusted from the AGC circuit 55 as described above. The changeover switch 76 is controlled by the system controller 47 to change over the switch piece c and responds to an operation of the key input operation unit 48 with an analog audio signal whose high frequency component is limited by the LPF 75 or an analog audio signal from the AGC circuit 55. Output selectively.

The analog audio signal selectively output from the changeover switch 76 is derived from the output terminal 77 as a LINE OUT output signal A _OTL , amplified by the amplifier 78, and output from the output terminal 79 to the headphone. It is derived as signal A _{OT H.} The analog audio signal supplied from the AGC circuit 55 via the changeover switch 76 is a sound monitor signal at the time of recording. The analog audio signal supplied from the LPF 75 via the changeover switch 76 is
It is a reproduction signal.

By the way, the magneto-optical disk 42 used in such an application example has 60 stereo audio signals.
It is desirable to set a recording capacity of at least one minute and up to about 74 minutes. For example, when the above-mentioned 1/4 data compression rate is adopted, about 130 M bytes is required. Also, in order to construct a portable or pocket-sized recording and / or reproducing apparatus, it is desirable to use a disk having an outer diameter of 8 cm or a smaller diameter. Further, regarding the track pitch and the linear velocity, the same track pitch as the CD, 1.6 μm, and the linear velocity of 1.2 to 1.4 m /
s is desired. As a disc satisfying these conditions, for example, the disc outer diameter is 64 mm, the data recording area outer diameter is 61 mm, and the data recording area inner diameter is 3 mm.
2 mm, the inner diameter of the lead-in area is 30 mm, and the center hole diameter is 10 mm. This disc is 70
When the disc is stored in a disc caddy of mm × 74 mm, recording / reproducing can be performed on the disc with a recording / reproducing device of a pocket size. Incidentally, the range of the inner and outer diameters of the data recording area of the disk for enabling recording / reproducing for about 72 minutes to 76 minutes in the ¼ data compression mode is as follows. Outer diameter 60 mm ~ 6
From 2mm, the outer diameter is 71mm-73 when the inner diameter is 50mm
It may be set appropriately within the range up to mm.

In such an application example, the servo control circuit 46, which is the servo control circuit of the present embodiment, can also change the adjustment value of the servo constant in response to the characteristic change due to the temperature of the optical pickup 42 as described above. It is possible to prevent the deterioration of servo characteristics due to the temperature of the environment.

The optical pickup drive control circuit according to the present invention is not limited to the above-mentioned embodiment, but may be applied when reading a signal from, for example, a read-only optical disc or a video disc. In addition, the configuration of the optical pickup is 3 beam Wollaston
A polarizing beam splitter may be used instead of the prism.

[0057]

In the optical pickup drive control device according to the present invention, the control unit causes the electronic volume to variably adjust the drive control constant of the optical pickup according to the temperature information near the optical pickup detected by the temperature sensor. The adjustment value can be changed according to the change in the characteristics of the drive control of the optical pickup due to the temperature, and the drive of the optical pickup can be controlled without depending on the environmental temperature.

[Brief description of drawings]

FIG. 1 is a block circuit diagram showing a configuration of an embodiment of an optical pickup drive control device according to the present invention.

FIG. 2 is a diagram showing a structure of an optical pickup.

FIG. 3 is a diagram showing a light receiving element surface of a photodetector of an optical pickup.

FIG. 4 is a block diagram showing a configuration of an application example to which the optical pickup drive control device according to the present invention can be applied.

FIG. 5 is a block circuit diagram showing a configuration of a conventional optical pickup drive control device.

[Explanation of symbols]

10 ... Optical pickup 31 ... Temperature sensor 32 ... Microcomputer 33 ... Digital / analog (D / A) converter 34 ... RF amplifier 35, 36 Volume 37 ... Servo signal generation circuit 38 ... Drive amplifier

Claims (2)

[Claims] 1. The drive of the optical pickup is controlled so that the optical pickup irradiates a recording track of the disc-shaped optical recording medium with a laser beam based on a signal obtained from reflected light from the disc-shaped optical recording medium. In an optical pickup drive control device, a temperature sensor that detects a temperature in the vicinity of the optical pickup, an electronic volume that variably adjusts a drive control constant of the optical pickup, and a temperature sensor that detects the temperature information detected by the temperature sensor. An optical pickup drive control device, comprising: a control unit that controls variable adjustment of an electronic volume. 2. The optical pickup drive control device according to claim 1, wherein the control unit detects a change amount of the temperature information detected by the temperature sensor by a microcomputer.