KR940002576B1 - Track status adjusting circuit - Google Patents

Abstract

The track position controller includes an input port for receiving an error signal, a charging/discharging circuit for storing the signal and discharging the signal at a predetermined level, a comparator for detecting the level of the signal output from the charging/discharging circuit and generating a jump signal, and a tracking actuator for controlling the position of track by the output signal of the comparator, thereby performing stable track jump.

Description

Track Position Control Circuit

1 is a timing diagram output from a conventional microcomputer.

2 is a circuit diagram showing an embodiment of a track position adjusting circuit according to the present invention.

* Explanation of symbols for main parts of the drawings

10: comparator C1, C2: condenser

D1, D2: Diodes R1, R2, R3: Resistance

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical pickup means installed in an optical recording and reproducing apparatus, wherein the recording means transfers pickup means to a desired track position on an optical disc and finally finds one track during recording or reproduction. The present invention relates to a track position control circuit for finding a track position by charging and discharging a tracking error signal detected by a tracking error detection circuit and applying a signal to a tracking actuator.

Generally, each player using an optical recording medium such as a CDP (Compact Disk Player), a CD-ROM, or the like is provided with optical pickup means for scanning a light beam such as a laser and detecting the light beam reflected from the medium. In such optical pickup means, a track in which information is recorded is applied to a tracking actuator wound around the objective lens driver by applying a predetermined current signal that detects the track position of the objective lens from the reflected light beam during recording or playback. Therefore, the objective lens is controlled to move and accurate tracking is achieved. However, if it is necessary to move to another track away from any track of the optical recording medium, the track position control of the objective lens moved by the signal applied from the tracking actuator makes it difficult to properly track the pickup means, so that the entire pickup means is connected to the sled motor. The tracking signal is applied to the tracking actuator by the tracking error signal applied by the tracking error detection circuit.

Conventionally, when a plurality of track jump command signals are applied to a microprocessor (hereinafter referred to as a "microcom"), the microcomputer may optically pick up the pick-up movement signal and the tracking actuator movement signal (of FIG. 1A) determined by a program in advance. A track jump was performed upon application of.

However, as shown in FIG. 1b, the predetermined jump period size does not satisfy the inner and outer circumference due to the difference in the number of tracks of the outer circumference in the CLV as it is applied to the tracking actuator during the predetermined period T1 in the microcomputer. .

Accordingly, an object of the present invention is to provide a track position adjusting circuit for adjusting the position of a track by adjusting the amount of a signal applied to a tracking actuator according to a pickup moving speed.

In order to achieve the above object, the present invention provides an optical recording and reproducing apparatus including a tracking error detector; An input terminal for introducing an error signal output from the tracking error detection circuit, a charge / discharge circuit which accumulates the signal introduced into the input terminal, and discharges the dust when a predetermined level is reached; Comparing means for generating a jump signal by comparing the detected and level detected signal with a reference signal and a reference signal, and a tracking actuator for adjusting the position of the track by the output signal of the comparing means.

Hereinafter, with reference to FIG. 2 according to the present invention will be described in detail. First, the configuration, the input terminal 5 for introducing the tracking error signal is connected to one side of the resistor (R1), the other side of the resistor (R1) is connected to one side of the capacitor (C1) and one side of the resistor (R2). On the other side of the capacitor C1, the base power source is connected to the second power source. The other side of the resistor R2 is connected to the input terminal of the comparing means 10 via a line L1 and connected to each connection point located on the line L1 between the resistor R2 and the comparing means 10. The cathode terminals of the resistor R3 and the capacitor 2 diode D1 are connected to the anode terminals of the diode 2, respectively, and include a resistor; One side of R3, one side of the capacitor 2, the positive end of the diode D1 and the negative end of the diode D2 are connected to a second power source, which is a base power source, respectively. And the output terminal of the comparing means 10 is connected to the tracking actuator.

The operation of the present invention will be described below. When the pickup means moves, the tracking error signal generated by the tracking error detector is introduced into the input terminal 5 and charged to the capacitor C1 via the resistor R1. The predetermined signal passing through the resistor R1 and the capacitor C1 passes through the current adjusting resistors R2 and R3 and passes through the capacitor C2. The signal from which the high frequency noise is removed from the condenser 2 is applied to the input terminal of the comparing means 10. The noise is generated by two diodes D1 and D2 located between the condenser C2 and the comparing means 10. The signal is removed. The comparison means 10 outputs a jump signal to be applied to the tracking actuator by comparing the signal introduced into the input terminal with a reference signal set in itself. The jump signal output from the comparing means 10 discharges the accumulated signal in the circuit composed of the resistor and the condenser during the track jump by a signal applied to the tracking actuator to perform a continuous operation. In other words, when the pickup means feed rate is high, the charge and discharge time is fast, so that the track jumps quickly, and when the pickup means feed rate is slow, the track jump speed is slowed down.

As described above, the amount of movement of the tracking actuator is determined in correspondence with the pick-up transfer speed, and thus the stable track jump is performed.

Claims (2)

An optical recording and reproducing apparatus including a tracking error detector, comprising: an input terminal for introducing an error signal output from the tracking error detection circuit, and a charge / discharge circuit for accumulating and injecting a signal introduced into the input terminal at a predetermined level And a comparing means for detecting a level of the signal output from the charging / discharging circuit and comparing the detected level with a reference signal to generate a jump signal, and a tracking actuator for adjusting the position of the track by the output signal of the comparing means. Track position control circuit comprising a. The track position control circuit as claimed in claim 1, further comprising a noise canceling section connected between said charge and discharge circuit and said comparison means for removing a noisy signal by a diode applied to said comparison means.