JPH0650571B2 - Optical disk player - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention will be described in the following order.

A Industrial field B Outline of the invention C Conventional technology D Problems to be solved by the invention E Means for solving problems F Working G Example G-1 Optical block part (Fig. 2) G -2 Principal part of disc player (Figs. 3, 4, 5) S-3 Concrete example of arithmetic processing unit (Fig. 6) H Effect of the invention A Industrial field The present invention is applied to a disc. The present invention relates to an optical disc player that irradiates a light beam to record or reproduce information.

B Outline of the Invention According to the present invention, when a disc is irradiated with a light beam to record or reproduce information, the incident position of the incident light beam on the disc is rapidly displaced in the radial direction of the disc toward an arbitrary target position. In an optical disc player having a function capable of performing a moving operation that causes a counter to count pulses obtained as the incident light beam crosses a track formed on the disk, and a moving operation of the incident light beam. Position data indicating the incident position of the incident light beam at the time of start, a target data indicating the target position where the incident position of the incident light beam should be reached, and an arithmetic processing unit for calculating position control data from the output data of the counter are provided, By controlling the movement of the incident position of the incident light beam based on the position control data obtained from the arithmetic processing unit, The movement of the incident light beam of the predicate, relatively small under the circuit arrangement is obtained by allowing performed in a short time.

C PRIOR ART An optical disc adapted to record information by irradiating a preformed spiral or circular-centric track with a light beam modulated with the information,
Alternatively, information such as digitized audio signals and video signals is recorded by forming spiral or concentric tracks, and the recorded information can be reproduced through irradiation of a light beam. In an optical disc, address information indicating a position on the optical disc, which is distinguished from information to be recorded or reproduced, is recorded on a track where information should be recorded or a track where information is recorded. In addition, in an optical disc player that records or reproduces information by irradiating a light beam on such an optical disc, the incident light beam on the optical disc is used by using the address information recorded on the optical disc. The incident position of is rapidly moved in the radial direction of the optical disc to an arbitrary target position, and an arbitrary position on the optical disc is Is it possible to perform recording or reproducing et information.

Conventionally, in order to rapidly move the incident position of the incident light beam to an arbitrary target position in the radial direction on the optical disc, the optical head part for making the light beam incident on the optical disc is mechanically moved in the radial direction of the optical disc. The position of the incident light beam closer to the target position, for example, to a position of about 200 tracks, and then a track jump signal is arranged corresponding to the optical head unit for tracking drive. By supplying to the coil and causing the incident light beam to repeatedly perform the track jump operation for one track, the incident position of the incident light beam is sequentially moved toward the target position by one track.

D Problem to be Solved by the Invention However, when the incident position of the incident light beam is rapidly moved to the target position, the track jump operation for one track of the incident light beam is performed based on the track jump signal. Requires, for example, a time of about 1 msec at a time. Therefore, as described above, the incident light beam is repeatedly moved for one track to move the incident position by about 200 tracks. When doing so, a time of around 20 msec is required, and there is a disadvantage that the incident position of the incident light beam cannot reach the target position in a short time.

In view of such a point, the present invention irradiates an optical disc with a light beam to record or reproduce information, by rapidly moving the incident position of the incident light beam on the optical disc in the radial direction of the optical disc. It is an object of the present invention to provide an optical disc player which can perform an operation for reaching an arbitrary target position in a short time and which requires a relatively small structure.

E Means for Solving the Problems In order to achieve the above-mentioned object, the optical disc player according to the present invention provides a disc with a light beam as shown in the basic configuration diagram of the present invention shown in FIG. Based on the reflected light beam from the disc, the optical block portion to be positioned, the tracking drive means that can move the incident light beam to the disc to change the incident position in the radial direction of the disc, When the moving operation is performed, a position control data is obtained by using a pulse generator that generates a predetermined number of pulses according to an incident light beam crossing a track formed on the disk, and the pulse from the pulse generator. Data generating means, digital / analog converter for converting the position control data obtained by the data generating means to analog, and incident light beam Until the value of the position control data from the start of movement becomes a predetermined value of zero or close to zero, and and a switching control unit for providing an output of the digital / analog conversion unit to the tracking driving means. Then, the above data generating means
The counter unit that counts the pulses from the pulse generator and sends the output data indicating the count value, the position data indicating the incident position at the start of the moving operation of the incident light beam, and the incident position of the incident light beam are reached. A control data forming unit that obtains a position control data to which an initial value corresponding to the difference is obtained, and a value of the position control data obtained by the control data forming unit is an initial value. And an arithmetic processing unit including a control data modifying unit that increases or decreases according to the count value indicated by the output data of the counter unit and moves toward zero.

F. Operation As described above, in the optical disc player according to the present invention, the moving operation is performed in which the incident position of the light beam incident on the disc from the optical block portion is rapidly displaced in the radial direction of the disc to reach the target position. In doing so, position data indicating the incident position at the start of the moving operation of the incident light beam and target data indicating the target position at which the incident position of the incident light beam should be reached are supplied to the arithmetic processing unit, The position control data forming means forms position control data provided with an initial value corresponding to the difference between the position data and the target data. This position control data is supplied from the arithmetic processing section to the digital / analog conversion section, and the output of the digital / analog conversion section based on the position control data is supplied to the tracking drive means via the switching control section to start the movement operation of the incident light beam. It

With the start of the incident light beam movement operation, a pulse from the pulse generator is obtained as the incident light beam crosses the track formed on the disk, and this pulse is counted by the counter unit and output data of the counter unit is counted. Is supplied to the arithmetic processing unit. Then, the position data of the position control data supplied from the arithmetic processing unit to the digital / analog converting unit is increased or decreased from the above-described initial value according to the count value of the counter to zero by the control data modifying unit of the arithmetic processing unit. It is sequentially modified so as to be directed, and accordingly, the movement operation of the incident light beam by the tracking drive means is continued in accordance with the modified position control data.

After that, when the value of the position control data modified by the control data modifying means becomes zero or a predetermined value near zero, the switching controller stops the supply of the output of the digital / analog converter to the tracking driving means, and the incident light The movement operation of the beam is ended. At this time, the incident position of the incident light beam is made to reach the target position or its vicinity, and further fine position adjustment is made as necessary to reach the target position.

In the optical disc player according to the present invention thus configured, the incident position of the incident light beam is gradually modified from the above-mentioned initial value according to the count value of the counter and is gradually changed to zero. The displacement is continuously made based on the position control data, and as a result, the target position is reached in a short time. Moreover, since the formation and modification of such position control data are performed in the arithmetic processing unit, the configuration of the portion that forms the control signal for moving the incident light beam is relatively small, and can be obtained inexpensively. Will be done.

G Example G-1 Optical block part (FIG. 2) FIG. 2 shows an optical block part used in an example of the optical disc player according to the present invention.

As described above, the disc 10 facing the optical block portion is adapted to record a film by irradiating a preformed spiral or concentric track with a light beam modulated by information. Information such as an optical disc or a digitized audio signal or video signal is recorded by forming a spiral or concentric circular track, and the recorded information can be reproduced through irradiation of a light beam. Address information indicating a position on the disc, which is distinguished from the information to be recorded or reproduced, on the track on which information is to be recorded or the track on which information is recorded. It was done. Also, disk 1
0 is rotated at a predetermined rotation speed.

The laser light source 21 emits a light beam modulated by the information when the information is recorded on the disc 10 and a light beam having a predetermined intensity when the information is reproduced from the disc 10. Then, the light beam sequentially passes through the collimator lens 22, the polarization beam splitter 23, the polarization beam splitter 24, and the 1/4 wavelength plate 25, and enters the objective lens 26. Then, the light beam is focused by the objective lens 26 and enters the disk 10. . Then, the reflected light from the disk 10 sequentially passes through the objective lens 26 and the quarter-wave plate 25 and enters the polarization beam splitter 24, and a part thereof is refracted to the right in FIG. System 27
The other part of the reflected light from the disk 10 which is incident on the polarization beam splitter 24, which is incident on the photodetector 31 which is divided into two for detecting the tracking error, is incident on the polarization beam splitter 23. The light is refracted in one direction and is incident on the photodetector 41 divided into four for focus error detection through the lens system 29.

In the example shown in FIG. 2, the entire optical block portion including the optical members from the laser light source 21 to the lens system 29 and the photodetectors 31 and 41 are supposed to be moved in the radial direction of the disk 10. Further, a polarization beam splitter 24, a quarter wavelength plate 25, an objective lens 26, a lens system 2
7 and the photodetector 31 are arranged at least in the radial direction of the disk 10 and the disk 1 with respect to the entire optical block portion.
The optical head portion 28 is configured to be movable in the direction orthogonal to the 0 plane. Then, with respect to the optical head portion 28, a tracking drive coil 32 for moving the optical head portion 28 in the radial direction of the disk 10 based on the tracking error signal, and a direction orthogonal to the surface of the disk 10 based on the focus error signal. A focus drive coil 42 for moving is provided.

G-2 Disc Player Main Part (FIGS. 3, 4, and 5) Next, with reference to FIG. 3, an example of an optical disc player according to the present invention including the above-mentioned optical block portion. The main part of is described.

In this example, the two detector elements 31 of the photodetector 31 are
The outputs of A and 31B are supplied to the subtraction circuit 33, and the subtraction circuit 33 obtains the tracking error signal TE based on the difference between the output of the detection element 31A and the output of the detection element 31B. On the other hand, the outputs of the two diagonal detection elements 41A and 41C of the photodetector 41 are supplied to the addition circuit 43, and the outputs of the other two diagonal detection elements 41B and 41D are added. Is supplied to. Then, the outputs of the adding circuits 43 and 44 are supplied to the subtracting circuit 45,
The subtraction circuit 45 obtains the focus error signal FE based on the difference between the sum of the outputs of the detection elements 41A and 41C and the sum of the outputs of the detection elements 41B and 41D. Further, the outputs of the adder circuits 43 and 44 are supplied to the adder circuit 46, and the adder circuit 46 detects the detection elements 41A, 41B, 41C and 41.
A signal based on the sum of the outputs of D, that is, a read signal according to the total amount of reflected light from the disk 10 (a signal that becomes a reproduction information signal when information is reproduced from the disk 10) R
F is obtained.

The tracking error signal TE obtained from the subtraction circuit 33
Is supplied to the terminal T of the switch 36 through the phase compensating circuit 34 and the amplifying circuit 35 in sequence, and the switch 36 is connected to the terminal T.
Is selected, it is supplied to the tracking drive coil 32 through the switch 36 and the drive circuit 37 in sequence, and a tracking servo control loop is formed. Further, the focus error signal FE obtained from the subtraction circuit 45 is supplied to the focus drive coil 42 through a phase compensation circuit, an amplification circuit and a drive circuit, which are not shown in the figure, to form a focus servo control loop.

The read signal RF obtained from the adder circuit 46 is the demodulation circuit 51.
When the information is recorded on the disc 10, the reproduction address information Q is obtained from the demodulation circuit 51, and when the information is reproduced from the disc 10, the reproduction address information Q and the reproduction program information P are obtained. To be Disk 10
If the information is reproduced from, the reproduction program information P
Is supplied to the program information processing circuit 52, and a reproduction program information signal A such as a reproduction audio signal or a reproduction video signal is obtained at the output terminal 53.

The reproduction address information Q is supplied to the decoding circuit 54, and the decoding circuit 54 obtains the position data K indicating the incident position of the incident light beam on the disk 10 which is represented by the reproduction address information Q and supplies it to the arithmetic processing unit 55. To be done.

The command signal generator 56 changes the target position of the incident light beam to the disc 10 when performing a rapid movement operation in which the incident position is rapidly displaced in the radial direction of the optical disc 10 to reach an arbitrary target position. This command signal generator 56 outputs target data I indicating the target position to be reached by the incident position of the incident light beam on the disk 10 based on the target position setting operation. It is obtained and supplied to the arithmetic processing unit 55.

In this manner, in addition to the position data K, the target data I is added to the position data K so that the incident light beam on the disk 10 is rapidly moved in the radial direction of the optical disk 10 toward the target position. When supplied to the arithmetic processing unit 55, the arithmetic processing unit 55 sends a rapid movement operation start signal Ss at the start of the rapid movement operation of the incident light beam, and also starts the rapid movement operation of the incident light beam. Position control data Dd provided with an initial value corresponding to the difference between position data K indicating the incident position of the incident light beam on the disk 10 at the time point and target data I indicating the target position at which the incident position of the incident light should reach. Is obtained. The initial value of the position control data Dd is proportional to the number of tracks formed on the disk 10 which the incident light beam should traverse until the incident position of the incident light beam reaches the target position.

Rapid movement operation start signal Ss obtained from the arithmetic processing unit 55
Is a reset-set flip-flop (hereinafter, R-
S.FF) 57 set terminal S is supplied. As a result, at the start of the rapid movement operation of the incident light beam, the RS-FF 57 is set and its output signal S
It is assumed that W takes a high level. This RS-FF5
The output signal SW having a high level of 7 is supplied to the switching control terminal of the switch 36, and the switch 36 is switched to the state of selecting the terminal J at the start of the rapid movement operation of the incident light beam.

The position control data Dd obtained from the arithmetic processing unit 55 is given with an initial value corresponding to the difference between the position data K indicating the incident position at the start of the rapid movement operation of the incident light beam and the target data I. , And is supplied to a digital / analog conversion circuit (hereinafter referred to as a D / A conversion circuit) 73 for digital / analog conversion. Then, the D / A conversion circuit 73
The output voltage DV obtained from the switch 3 is supplied to the terminal J of the switch 36 through the phase compensation circuit 74, and further, the switch 3
Since 6 selects the terminal J, it is supplied to the tracking drive coil 32 through the switch 36 and the drive circuit 37 sequentially.

At this time, for example, when the target position to be reached by the incident position of the incident light beam on the disc 10 is inside the disc 10 from the incident position at the start of the rapid movement operation of the incident light beam, Position data K indicating the incident position at the start of the rapid movement operation and target data I
The difference between the absolute value and the absolute value depends on the distance from the incident position to the target position at the start of the rapid movement operation of the incident light beam. It is set to a negative value proportional to the number of tracks to be traversed, and therefore, the initial value given to the position control data Dd is such that the incident light beam should traverse by the absolute value until the incident light beam incident part position reaches the target position. Negative value proportional to the number of tracks. Therefore, as shown in FIG. 4A, the output voltage DV of the D / A conversion circuit 73 has an absolute value whose absolute value is the incident position of the incident light beam at the start time t ₀ of the rapid movement operation of the incident light beam. 2 becomes a negative value proportional to the number of tracks that the incident light beam should traverse, and the optical head portion 28 shown in FIG.
Therefore, the incident position of the incident light beam on the disk 10 is
The disc 10 is moved inward in the radial direction of the disc 10.

On the contrary, when the target position is outside the disk 10 from the incident position at the start of the rapid movement operation of the incident light beam, position data K indicating the incident position at the start time of the rapid movement operation of the incident light beam is stored. The difference between the target data I and the target data I depends on the distance from the incident position at the start of the rapid movement operation of the incident light beam to the target position, until the incident position of the incident light beam reaches the target position. The light beam is set to a positive value proportional to the number of tracks that the light beam should traverse. Therefore, the initial value given to the position control data Dd has an absolute value of the incident light beam before the incident position of the incident light beam reaches the target position. Becomes a positive value proportional to the number of tracks that should cross. Therefore, as shown in FIG. 4B, the output voltage DV of the D / A conversion circuit 73 has an absolute value whose absolute value is the incident position of the incident light beam at the start time t ₀ of the rapid movement operation of the incident light beam. 2 becomes a positive value that is proportional to the number of tracks that the incident light beam should traverse, and the optical head portion 28 shown in FIG. It is moved in the radial direction of 10 toward the outside of the disk 10.

On the other hand, the read signal RF obtained from the addition circuit 46 and the tracking error signal TE obtained from the subtraction circuit 33 are supplied to the pulse generation circuit 70.

Then, when the incident position of the incident light beam on the disc 10 is moved in the radial direction of the disc 10, the read signal RF is the disc 10 at the incident position of the incident light beam.
Changes depending on the position of each of the tracks formed in, and becomes maximum when the incident position is at the center of the track,
It is minimum when it is in the middle of two adjacent tracks.

On the other hand, in the tracking error signal TE when the incident position of the incident light beam on the disc 10 is moved in the radial direction of the disc 10, the incident position is at the center of the track and between the two adjacent tracks. At that time, it becomes zero, and positive and negative values alternate between them, and the phase with respect to the read signal RF is such that the incident position of the incident light beam moves from the outer side to the inner side in the radial direction of the disk 10. It will be reversed when it is pushed and when it is moved from the inside to the outside. For example, when the incident position of the incident light beam is moved from the outer side to the inner side of the disk 10, the tracking error signal TE has a phase of 90 degrees with respect to the read signal RF as shown in FIG. 5A. When there is a delay, and when the incident position of the incident light beam is moved from the inner side to the outer side of the disk 10, the tracking error signal TE becomes the read signal RF as shown in FIG. 5B. On the other hand, the relationship has a phase lead of 90 degrees.

Then, the pulse generation circuit 70 moves the incident position of the incident light beam on the disk 10 toward the inner side of the disk 10 in the radial direction of the disk 10 based on the relationship between the read signal RF and the tracking error signal TE. At this time, a constant number of pulses DP are generated each time the incident light beam crosses each track formed on the disk 10, and the incident position of the incident light beam is outside the disk 10 in the radial direction of the disk 10. As it is moved towards it, it produces a pulse UP, a constant number of which is obtained each time the incident light beam traverses a track formed on the disk 10.

The pulse DP or UP obtained from the pulse generation circuit 70 is supplied to the counter 72. Counter 72
Is supplied with the rapid movement operation start signal Ss sent from the arithmetic processing unit 55 at the start of the rapid movement operation of the incident light beam on the disk 10, thereby making it possible to perform the counting operation and generating the pulse. The pulse DP or UP from the circuit 70 is counted, and the counted value is counted as the pulse DP.
In the case of the count value of the pulse UP, the output data Dc is shown as a negative number, and in the case of the count value of the pulse UP, as a positive number, the output data Dc is supplied to the arithmetic processing unit 55.

The arithmetic processing unit 55 to which the output data Dc of the counter 72 is supplied reads the output data Dc and performs an arithmetic operation for subtracting the output data Dc from the position control data Dd, and the value of the position control data Dd is set to the value of the incident light beam. The initial value, which is proportional to the number of tracks that the incident light beam should traverse by the time the incident position reaches the target position, is changed to a value obtained by subtracting the value corresponding to the count value of the counter 72. That is, the position control data Dd takes an initial value that is proportional to the number of tracks that the incident light beam should traverse by the time the incident position of the incident light beam reaches the target position. According to the counting operation of the counter 72, the value corresponding to the numerical value is subtracted to take a value toward zero.

As a result, when a rapid movement operation of the incident light beam is performed in which the incident position of the incident light beam is moved toward the inner side of the disc 10 in the radial direction of the disc 10, the position control data Dd obtained from the arithmetic processing unit 55 is obtained. The value becomes a negative value whose absolute value is proportional to the number of tracks that the incident light beam should traverse by the time the incident position of the incident light beam reaches the target position at the start of the rapid movement operation of the incident light beam, and then The pulse DP is obtained from the pulse generation circuit 70, and as it is counted by the counter 72, it goes to zero and eventually becomes zero. As a result, the output voltage DV of the D / A conversion circuit 73 also gradually decreases from a negative value at the start time t ₀ of the rapid movement operation of the incident light beam to zero as shown in FIG. 4A, and at time t ₁ . It takes a voltage value of zero.

On the contrary, the incident position of the incident light beam is at the disk 10
When the sudden movement operation of the incident light beam that is moved toward the outside of the disk 10 in the radial direction is performed, the value of the position control data Dd obtained from the arithmetic processing unit 55 is
At the start of the rapid movement operation of the incident light beam, the absolute value becomes a positive value proportional to the number of tracks that the incident light beam should traverse by the time the incident position of the incident light beam reaches the target position. Pulse UP from 70
Is obtained, and as it is counted by the counter 72, it approaches zero, and eventually becomes zero. As a result, the output voltage DV of the D / A conversion circuit 73 also gradually becomes zero from the positive value at the start time point t ₀ of the rapid movement operation of the incident light beam, as shown in FIG. 4B, and at the time point t ₁ . It takes a voltage value of zero.

As described above, at the time t ₁ when the value of the position control data Dd obtained from the arithmetic processing unit 55 becomes zero, the incident position of the incident light beam is at the target position or at the front position thereof or a position near the target position. In the example, after the time t ₁ , the arithmetic processing unit 55, for example, the position control data Dd for a predetermined predetermined short period set by a built-in timer.
Is further modified according to the counting operation of the counter 72. Fine adjustment of the incident position of the incident light beam is performed based on the output voltage DV of the D / A conversion circuit 73 obtained according to the modification of the position control data Dd in a predetermined predetermined short period after the time t _1. That is, at the time point t ₁ , the incident position of the incident light beam that was near the target position is also made to reach the target position.

Then, when a predetermined short period of time elapses after time t ₁ , the rapid movement operation end signal Se is output from the arithmetic processing unit 55.
Is sent. At this time, the value of the position control data Dd obtained from the arithmetic processing unit 55 is zero or a predetermined value near zero. This rapid movement end signal Se is R
It is supplied to the reset terminal R of the S-FF57. As a result, the RS-FF 57 is reset and the output signal SW thereof is set to the low level, and accordingly, the switch 36 is switched to the state of selecting the terminal T, and the incident position of the incident light beam on the disk 10 is changed. The rapid movement operation of rapidly displacing the disk 10 in the radial direction of the disk 10 is completed. Therefore, the switch 36 operates from the start of the rapid movement operation of the incident light beam to the disk 10 until the value of the position control data Dd obtained from the arithmetic processing unit 55 becomes zero or a predetermined value near zero. D / A conversion circuit 73
Will be supplied to the tracking drive coil 32 via the drive circuit 37. Then, after the switch 36 is switched to the state of selecting the terminal T and the rapid movement operation of the incident light beam with respect to the disk 10 is completed, normal tracking servo control based on the tracking error signal TE is performed.

G-3 Concrete Example of Arithmetic Processing Section (FIG. 6) The arithmetic processing section 55 for forming and modifying the position control data Dd as described above is constituted by, for example, a microcomputer having a built-in counter. An example of the control program executed by the microcomputer will be described with reference to the flowchart shown in FIG.

In the example of this program, after the target data I is supplied from the command signal generator 56 to start, the process 81 sends the rapid movement operation start signal Ss. Next, in process 82, the difference between the position data K from the decoding circuit 54 and the target data I is obtained, and based on this difference, the incident position of the incident light beam on the disk 10 is incident until it reaches the target position. The position control data Dd having a positive or negative initial value that takes an absolute value proportional to the number of tracks that the light beam should traverse is formed.

Then, in process 83, the output data Dc of the counter 72
In the subsequent process 84, the position control data Dd is read.
Is calculated by subtracting the output data Dc from the counter 72, and the position control data Pd takes an absolute value proportional to the number of tracks that the incident light beam should traverse until the incident position of the incident light beam reaches the target position. The value is changed to a value obtained by subtracting the count value of the counter 72 indicated by the output data Dc from the positive or negative initial value.

Then, in the decision 85, the position control data D
It is determined whether the value of d has become zero. If the value of the position control data Dd is not zero, the process returns to the process 83,
The processes in the processes 83 and 84 are performed, and this is repeated until the value of the position control data Dd becomes zero. When the value of the position control data Dd becomes zero, the process proceeds to process 86 and the built-in timer is started. In this timer, a preset short time Tt is set as the time to be measured. Next, in process 87, the output data Dc of the counter 72 is read in the same manner as in process 83, and in the following process 88, the output data Dc of counter 72 is subtracted from the position control data Dd in the same manner as in process 84. The position control data Dd is further modified according to the count value of the counter 72 indicated by the output data Dc.

Then, in the decision 89, it is determined whether or not a predetermined short time Tt set by the timer has elapsed. If the predetermined short time Tt has not elapsed, the process returns to the process 87, the processes 87 and 88 are performed, and this is repeated until the predetermined short time Tt elapses. When the predetermined short time Tt has elapsed, the process proceeds to process 90, where the rapid movement operation end signal Se is sent and the control ends.

In this way, based on the rapid movement operation start signal Ss, the position control data Dd and the rapid movement operation end signal Se obtained through the control according to the operation procedure shown in the flowchart of FIG. The incident light beam is rapidly moved.

H Effect of the Invention As is apparent from the above description, according to the optical disc player of the present invention, the incident position of the incident light beam on the optical disc is displaced in the radial direction of the optical disc to reach the target position. The moving operation to be performed is formed by giving an initial value according to the difference between the position data indicating the incident position of the incident light beam and the target data indicating the target position at the start of the moving operation. , The value of which is modified based on position control data to be directed to zero according to the count value of the pulses obtained in response to the incident light beam on the optical disc traversing the track formed on the optical disc. , Thereby moving the incident position of the incident light beam on the optical disc in the radial direction of the optical disc to reach an arbitrary target position in an extremely short time. It will be able to carry out within the. Moreover, since the formation and modification of such position control data are performed in the arithmetic processing unit, the configuration of the portion that forms the control signal for moving the incident light beam to the optical disc is relatively small, It will be cheaply obtained.

[Brief description of drawings]

FIG. 1 is a diagram showing a basic configuration of the present invention corresponding to the claims, and FIG. 2 is a schematic configuration diagram showing an optical block portion used in an example of an optical disc player according to the present invention,
FIG. 3 is a block connection diagram showing an essential part of an example of an optical disc player according to the present invention, FIGS. 4A and 4B, and FIGS. 5A and 5B are operation explanations of the example shown in FIG. FIG. 6 is a waveform diagram provided, and FIG. 6 is a flowchart showing an example of a control program executed by the microcomputer used in the arithmetic processing section in the example shown in FIG. In the figure, 10 is a disk, 28 is an optical head portion, 32 is a tracking drive coil, 36 is a switch, 37 is a drive circuit, 55 is an arithmetic processing section, 57 is an RS-FF, 70 is a pulse generation circuit, and 72 is The counter 73 is a D / A conversion circuit.

Claims (1)

[Claims] 1. An optical block unit for making a light beam incident on a disc on which information is recorded or reproduced by irradiating the optical beam, and an incident light beam from the optical block unit to the disc is made incident on the disc. When the moving operation of the incident light beam is performed on the basis of the tracking driving means that is capable of performing the moving operation for displacing the position in the radial direction of the disk, and the reflected light beam from the disk, A pulse generating section for generating a predetermined number of pulses in response to the emitted light beam crossing a track formed on the disk; and a counter section for counting the pulses from the pulse generating section and transmitting output data indicating a count value. Position data indicating the incident position on the disk at the start of the moving operation of the incident light beam and the disc of the incident light beam. Control data forming means for obtaining a position control data to obtain a difference from target data indicating a target position at which the incident position on the cursor should reach, and to obtain position control data to which an initial value corresponding to the difference is given.
And an arithmetic processing unit including a control data altering unit that increases or decreases the value indicated by the position control data from the initial value according to the count value indicated by the output data of the counter unit and moves toward zero, and the arithmetic processing unit A digital / analog converter for digital / analog converting the obtained position control data, and from the start time of the moving operation of the incident light beam until the value indicated by the position control data becomes zero or a predetermined value near zero. An optical disc player comprising: a switching control section for giving the output of the digital / analog conversion section to the tracking driving means.