KR970008280B1 - Fast track search device of optical disk - Google Patents

Abstract

A high speed track search device of an optical disc is provided to search an object track at a high speed. The device comprises a rotational member(2) which is fixedly installed at the rotary shaft of a sled motor(1) and which is marked on one side thereof; a light sensor(3) which has a light emitting device(3A) and a light receiving device(3B) and detects the marking of the rotational member(2); an amplifier(4) which amplifies the output of the optical sensor(3); a wave forming section(5) which forms the amplified signal to a pulse shape; and a micro computer(6).

Description

High speed track search device of optical disc

1 is a diagram showing a fast track search apparatus for an optical disc according to the present invention.

2 is a control flowchart for explaining the control operation of the microcomputer shown in FIG.

* Explanation of symbols for main parts of the drawings

1: sled motor 2: rotating member

3: light sensor 4: amplifier

5: waveform shaping part 6: microcomputer

7: motor drive part 8: encoder

9: memory 10: spindle servo

11: spindle motor 12: compact disc

13-15: Gear 16: Rack gear

17: optical pickup

The present invention relates to a high speed track search apparatus for an optical disk, and more particularly, to a high speed track search apparatus for detecting a rotation speed of a sled motor and searching a target track at a high speed by the rotation speed of the sled motor. It is about.

In general, the tracks of optical discs such as laser discs (LD), compact discs (CD) and magneto-optical discs are listed at very fine intervals of approximately 1.6 μm, and the number of such tracks is approximately 2 for an hour-long disc. There are full bloom tracks. Therefore, when looking at the optical disc microscopically, it is a realistic problem that there is no choice but to rotate with eccentricity.

The function of the tracking servo is to inject a laser beam while accurately finding such a track, and the basic operation of the servo is to radially move the objective lens and the optical pickup body based on an electrical signal corresponding to the light reception state of the laser beam. By modifying the position of the track to be tracked.

There are two ways to move the beam: moving the optical pickup body and moving the objective lens laterally. The electrons have a large inertial mass, which makes it impossible to move quickly, but instead it can move largely. Do. In the latter case, since the actuator (objective lens and the driving unit) is light in weight, high-speed response is possible, but the moving range is limited because of its narrow moving range. Therefore, when jumping a track, the pickup body is first moved by the sled motor to select the rough position, and then the target track is caught. Then, the sled motor is restarted to correct the pickup position so that the objective lens is positioned at the center of the optical system.

In the optical disc mechanism employing the conventional 3-beam method (rack and pinion method) as the tracking servo method, the target track is searched by moving the pickup by moving the sled motor to find the target track and counting the number of tracks. Therefore, there was a problem that it takes too much time to perform a long track jump while counting tracks of approximately 1.6 μm.

Accordingly, the present invention has been made in view of the above circumstances, and the rotational speed of the sled motor is detected based on the light reflected from the rotating member by an optical sensor while the rotating member is fixed to the sled motor shaft. In addition, an object of the present invention is to provide a high-speed track search apparatus for an optical disk that enables the target track to be searched at a high speed by the rotational speed of the sled motor.

According to the high-speed track search apparatus for an optical disk according to a preferred embodiment of the present invention for achieving the above object, the optical pickup by a sled motor, a motor driving unit for driving the sled motor, the driving force of the sled motor An optical disk apparatus having a conveying mechanism for conveying a light; An optical sensor fixedly installed on the rotating shaft of the sled motor and composed of a rotating member marked at equal intervals on one surface thereof, a light emitting element and a light receiving element to detect the marking of the rotating member, and amplifying the output of the optical sensor. An amplifying section, a waveform shaping section for waveform shaping the amplified signal in a pulse state, reading absolute time information of each song recorded in the TOC area of the optical disc, calculating a track number of each song, and tabulating the track numbers; The motor rotation speed and rotation angle of each song are calculated, tabled and stored in a memory, and a table for the rotation speed and rotation angle of the sled motor stored in the memory is read out for the target track, and based on the target track Controlling the motor driving part while counting pulse signals from the waveform shaping part by the number of revolutions and the rotation angle of the sled motor corresponding to That having been made in the yikeom characterized.

Here, the microcomputer determines whether the target track jump is a long track jump of a predetermined track or more, and when the track is long track jump, reads the motor speed and the rotation angle of the target track from the table stored in the memory. The motor drive unit is controlled while counting the pulse signal from the waveform shaping unit in response to the rotation angle, while the motor drive unit is controlled by counting the number of tracks detected by the optical pickup in the case of not long track jumping. It is desirable to search.

The microcomputer ends the track search based on the pulse signal from the waveform shaping part when the count value of the pulse signal from the waveform shaping part reaches the motor rotation speed and the rotation angle from the table when the long track jump is performed. It is preferable to search the target track by controlling the motor driving unit while counting the number of tracks detected by the optical pickup.

According to the present invention configured as described above, the correlation between the number of tracks of the optical disc and the rotational speed and rotational angle of the sled motor is defined, and based on this correlation, the sleds of the rotating members marked at equal intervals on one side thereof are marked. It is fixed to the rotating shaft of the motor, and when the sled motor rotates to detect the marking of the rotating member by an optical sensor to control the rotation speed and the rotation angle to the target track. Therefore, since the track can be counted in large units, the long track jump can be performed at high speed.

Hereinafter, a high speed track search apparatus for an optical disc according to the present invention will be described in detail with reference to the accompanying drawings.

1 is a diagram showing a high-speed track search apparatus for an optical disk according to the present invention, wherein reference numeral 12 denotes an optical disk such as a laser disk (LD), a compact disk (CD), a magneto-optical disk, and the like. It is a spindle motor for rotating at a predetermined rotation speed (for example, about 1800 rpm in the inner circumference), and 10 is a spindle servo which controls the rotation of the spindle motor 10 by the control of the following microcomputer 6.

Reference numeral 17 denotes an optical pickup for reading data recorded on the optical disc 12, and 8 denotes an optical pickup 12 read from the optical disc 12 by the optical pickup 17 according to a control signal of the microcomputer 6 below. The decoder decodes the data by the EFM (Eight to Fourteen Modulation) method, and 9 is a memory for storing data (for example, TOC data) decoded and output by the decoder 8.

Further, reference numeral 1 denotes a sled motor for generating power for transferring the pickup, a rack gear for moving the pickup while supporting the pickup 17 of 16, and 13 to 15 for the sled motor 1; A plurality of gears for transmitting the rotational force of the rack gear 16.

In addition, reference numeral 2 is a rotating member fixed to the rotating shaft of the sled motor 1 and marked at equal intervals on one side thereof, and the rotating member 2 attaches silver foil to one surface of the thin disc-shaped plastic. A plurality of thin fan-shaped black sheets 2A are attached on the foil paper at predetermined equal intervals so that the silver portion is a reflective surface for reflecting light, and the black portion is a non-reflective surface for the reflection of light reflected from the reflective surface. The amount of rotation can be detected and the number of revolutions can be read.

In addition, reference numeral 3 is an optical sensor configured to include a light emitting element 3A and a light receiving element 3B to detect the marking of the rotating member, 4 is an amplifying unit for amplifying the output of the optical sensor 3, and 5 A waveform shaping unit outputs the amplified signal by waveform shaping in a pulse form.

Reference numeral 6 reads the absolute time information of each track recorded in the TOC area of the optical disc 12, calculates the track number of each track, and tabulates the track numbers, and shows the motor rotation speed and rotation angle of each track. Calculate and make a table and store the result in the memory 9, and read out a table for the rotational speed and rotational angle of the sled motor 1 stored in the memory 9 with respect to the target track and based on the target track. The microcomputer controls the motor driving section 7 while counting pulse signals from the waveform shaping section 5 corresponding to the rotational speed and the rotation angle of the sled motor 1 corresponding to.

Next, the operation of the high-speed track search apparatus of the optical disc according to the present invention configured as described above will be described in detail with reference to the control flowchart shown in FIG.

First, when the power is turned on, the microcomputer 6 accesses the TOC area of the optical disc 12 through the optical pickup 17 to read data, and stores the read data in the memory 8 via the decoder 8. (Step S1).

After that, in step S2, the microcomputer 6 reads the absolute time information of each recording content (e.g., song) recorded on the optical disc 12, and track number information of the start position of each recording content (e.g., music) in step S3. Is calculated and a track number table for each recorded content (e.g., a song) is created and stored in the memory 9.

Subsequently, in step S4, the microcomputer 6 calculates the motor rotation speed and rotation angle corresponding to the recording contents (for example, the music) based on the track number table in the step S3, and prepares a table according to the memory 9 Store in

Next, in step S5, the microcomputer 6 determines whether the current track jump is a long track jump that moves more than a predetermined track (for example, 200 tracks), and if it is not a long track jump, the control proceeds to step S9. In the case of the long track jump, the table of the rotation speed and the rotation angle of the sled motor stored in the memory 9 is accessed to read the motor rotation speed and the rotation angle of the target track, and then the sled motor ( 1) is started and the pulse signal from the waveform shaping section 5 is counted.

Then, in step S8, it is determined whether the count value of the pulse signal from the waveform shaping section 5 reaches the motor rotation speed and the rotation angle from the table, and when it reaches, the control proceeds to step S9 and the waveform shaping section ( The track drive based on the pulse signal from 5) is finished, and the motor drive unit 7 is controlled while counting the number of tracks detected by the optical pickup 17 to search for the target track.

Next, in step S10, it is determined whether the target track is reached, and when the target track is reached, control is terminated.

As described above, according to the high-speed track search apparatus of the optical disk according to the present invention, the correlation between the number of tracks of the optical disk, the rotational speed and the rotational angle of the sled motor is defined, and based on the correlation, one side is spaced at equal intervals. The rotating member is fixed to the rotating shaft of the sled motor, and the marking of the rotating member is detected by an optical sensor at the time of rotation of the sled motor, thereby controlling the rotation speed of the rotation speed to the target track. Therefore, it is not necessary to count tracks individually by optical pickup at the time of long track jumping, and the tracks can be counted in large units, so that long track jumping can be performed at high speed.

Claims (3)

Transfer mechanism 13 to 16 for transferring the optical pickup 17 by the sled motor 1, the motor driving unit 7 for driving the sled motor 1, and the driving force of the sled motor 1; In the optical disk device having a), the rotating member 2 is fixed to the rotating shaft of the sled motor and is composed of a rotating member 2 marked at equal intervals on one surface thereof, and a light emitting element 3A and a light receiving element 3B. An optical sensor 3 for detecting the marking of the member 2, an amplifying unit 4 for amplifying the output of the optical sensor 3, a waveform shaping unit 5 for waveform shaping the amplified signal in a pulse form, The absolute time information of each song recorded in the TOC area of the optical disc 12 is read out, the track number of each song is calculated, the track numbers are tabulated, the motor rotation speed and the rotation angle of each song are calculated, and the table is stored in memory. The sled stored in the memory 9 with respect to a target track Reading the table of the rotational speed and the rotational angle of the rotor and counting the pulse signal from the waveform shaping section 5 as much as the rotational speed and rotational angle of the sled motor 1 corresponding to the target track based on this. A high speed track search apparatus for an optical disc, characterized in that it comprises a microcomputer (6) for controlling the motor drive unit (7). 2. The motor speed and rotation of the target track according to claim 1, wherein the microcomputer (6) determines whether the target track jump is a long track jump of a predetermined track or more, and is a long track jump from the table stored in the memory (9). The motor driving unit 7 is controlled while reading the angle and counting the pulse signal from the waveform shaping unit 5 corresponding to the motor rotational speed and the rotational angle. 17. A high-speed track search apparatus for an optical disc, characterized in that the motor drive unit (7) is controlled while counting the number of tracks detected by 17) to search for a target track. 3. The waveform forming unit (5) according to claim 2, wherein the microcomputer (6) is the long track jump when the count value of the pulse signal from the waveform forming unit (5) reaches the motor rotation speed and rotation angle from the table. High speed track of the optical disc, characterized in that the target drive is searched by controlling the motor drive unit 7 while counting the number of tracks detected by the optical pickup 17 after finishing the track search based on the pulse signal from Search device.