SU1278953A1 - Device for tracking information track of optical disk information medium - Google Patents

Abstract

The invention relates to an information accumulation technique and allows to increase the accuracy and reliability of tracking an information track. The alternating voltage generator 10 generates a signal of a fixed frequency, fed through summing amplifier 11 and power amplifier 12 to the input of actuator 13 for tracking the information track of the disk carrier, which scans the reproduction light beam across the information track with a small amplitude. The photodetector unit 1 generates a signal proportional to the modulated light flux. Using a low-pass filter 2, a scan signal is extracted to the input of the synchronous switch 3. The generator 10 also generates a reference signal and supplies it to the input of the synchronous switch 3. As a result of the synchronous detection, the output of the differential amplifier 4 produces a error signal, which indicates the value and the direction of displacement of the reproduction light beam. Analog-to-digital converter 5 converts the error signal to digital form and supplies it to the input of dividing circuit 6. The low-pass filter 7 allocates a constant component of the photoreceiver unit 1, which is converted by the analog-digital press S by the generator 8 to digital form and is also fed to the input of the dividing circuit 6. The signal (L mismatch is converted to analogue by a digital-to-analog converter 9, passes to the input of summing amplifier 11 and, through power amplifier 12, controls the tracking mechanism 13, which shifts the reproduction light beam in accordance with the care of the information track ts, carried out continuous tracking. 1 Il. oo co eo oo

Description

The invention relates to an information storage technique, in particular, to devices for reproducing information from optical disk media.

The purpose of the invention is to improve the accuracy and reliability of tracking the information track.

The drawing shows a diagram of the device.

The device contains a photodetector unit 1, a first lowpass filter 2, a synchronous switch 3, a differential amplifier 4, a first analog-to-digital converter 5, a dividing circuit 6, a second low-pass filter 7, a second analog-to-digital converter 8, a digital-to-analog converter 9, a generator 10, a summing amplifier 11, a power amplifier 12 and a tracking actuator 13.

The device works as follows.

The alternating voltage generator 10 generates a signal of a fixed frequency, fed through a summing amplifier 11 and a power amplifier 12, on the input of the actuator 13 for tracking the information track of the disk carrier that scans the reproduction light beam across the information track with a small amplitude, for example, one tenth of the diameter of the light. beam. The photodetector unit 1 generates a signal proportional to the modulated luminous flux. The first low-pass filter 2 (or band-pass filter) extracts the scan signal, which is fed to the input of the synchronous switch 3. The generator 10 also generates a reference signal that is phase aligned, for example, using a phase shifter (not shown) with the selected band-pass signal filter 2 (or low pass filter), and feeds it to the control input of the synchronous switch 3. As a result of the synchronous detection, the output of the differential amplifier 4 is the error signal SR, which indicates t by the magnitude and direction of displacement of the reproduction light beam relative to the center of the information track. The first analog-to-digital converter 5 converts the error signal into digital form and provides it to the input of the numerator of the 6-dividing circuit. The second low-pass filter 7 allocates a constant component So of the signal of the photoreceiver unit 1, which indicates its level of illumination. The signal So is digitized by a second analog-digital conversion.

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Inverter 8 and is fed to the input of the "Z tel circuit 6 division. As a result of the division scheme, SB / SO is formed. Since the signal lines SR and S ,, od depend on parameters such as the radiation of the reproducing laser and the reflectance of the optical carrier of a carrier, the Sn / Su pattern obtained in this way is independent of the nnh. This mismatch is transferred to the apal form of the digital-analogue & transformer 9, passes to the second input of the sum amplifier 1 and controls the power of the tracking 13 through the power amplifiers, which will displace the bias beam in a continuous manner. living

The operation of the DEVICE requires that the mobility of the radiation of a laser to be produced by the scattering coefficient of the reflection of the carriers of the pyromacnea e: optical spectrum k from low noise.

F o rl l l i

The device of the dc track | of the disc track of the optical disk info ()) matsli track containing a thread tracking system, connected to the photonic unit of which is connected to the inputs of the first filter through the bottom filter} { The synchronous switch, whose control input with the generator output, which is also with the first summing telephone input, the synchronous switching outputs, is connected to the differential inputs of the power amplifier, and the output of the summing of its bodies through the power amplifier with the input by raising type and reliability of the information track, in the first and second analog digital diggers, the second phi, the 1st subdivision scheme and the C1 F1 analogue mapper, the output of the output through the second phi; the 1st) the bottom of the bottom often logo-new output npecj with with the input of the dividend circuit of which, via a digital-to-analog converter, is connected to the second input ruup1, its amplification; 1, and

FET; -1C amplifier through an analog-to-digital converter with an input divider of the dividing circuit. Compiled by S. Ilchuk

Editor S. PekarTe.krel I. VrosKorrek; (I M (zmborska

Order 6777/52 Circulation 543 1o ;; giicnuc

VNIIPI State Committee of the SS (R

inventions n discoveries

113035, Moscow, Zh-35, Raushsk nab. 4/5

Branch PPP "Patent, Uzhgorod, st. Design. four

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The borrower is 8 and is fed to the input of the Denominator of the 6-division scheme. As a result, the SB / SO signal is generated at the output of the dividing circuit. Since the signals of SR and S are equally dependent on parameters such as mop1, the reproducing laser radiation and the reflectance of the optical disk media, the Sn / Su signal thus obtained is independent of nnh. This mismatch signal is converted into an apalO-form digital-analogue & converter 9, passes to the second input of summing amplifier 1, and controls power amplifier 12 through the tracking mechanism 13, which biases the light beam by repeating: and according to the departure of the information track, thus implemented continuous tracking.

The operation of the DEVICE does not depend on the stability of the mobility of the laser radiation, the reproducibility, the scatter of the reflection coefficients of the pyromatrix ma, e: optical spectrum parameters k from low-frequency noise.

F o rl l l i

The device of dl sg | xsm1i behind the information track of the optical disk info ()) matsli containing the performance of the tracking system optically associated with the photonometric unit, the output of which is connected to the inputs through the first low-pass filter }} {a hropic switch whose control input is connected to the generator output, which is also connected to the first summing amplifier's output, the outputs of the synchronous switch are connected to the inputs of the differential power amplifier, and the output of its amplifier through the power amplifier binding spine. It is connected with the input of the tracking actuator, characterized in that, in order to improve the accuracy and reliability of tracking the information track, the first and second analog-to-digital converters, the second phi, the low pass, the dividing circuit and the C1-1 analogue converter, the output of on b. Yuka is connected to the input of a divisible division scheme, the output of which is connected to the second input of the sum.Miruyup1, its amplification; 1, and the first differentiator through the digital-to-analog converter; A -1c amplifier through an analog-to-digital converter with an input of the divider of the dividing circuit. tavitel S. Ilchuk

first connected

Claims (1)

FORUM I invented Device · for tracking the information track of a disk optical information carrier, comprising an actuating tracking mechanism, optically coupled to a photodetector unit, the output of which is connected through the first low-pass filter to the input of the synchronous switch, the control input of which is connected to the output of the generator, which is also connected to the first input summing amplifier, the outputs of the synchronous switch are connected to the inputs of the differential amplifier, and the output of the summing amplifier through the power amplifier with knitted with the input of the tracking actuator, characterized in that, in order to improve the accuracy and reliability of tracking. behind the information track, the first and second analog-to-digital converters, a second low-pass filter, a division circuit and a digital-to-analog converter, the output of the photodetector are introduced into it through the second low-pass filters and an analog-to-digital converter connected to the input of the divisible division circuit, the output of which through a digital-to-analog converter is connected to the second input of the summing amplifier, and you the course of the first differential amplifier through the first analog-to-digital converter is connected to the input of the divider of the division circuit.