RU1778782C - Optomechanical memory device - Google Patents

Abstract

The invention relates to a technique for storing information, in particular to optical-mechanical storage devices, and allows to increase the accuracy and reliability of recording information reproduction. The goal is achieved by integrating an integrator, an electronic switch, a comparator and a pulse generator with pulse-width modulation, and the output of the phase detector through an integrator connected to the inputs of a pulse generator with pulse-width modulation, the output of which is connected to the first input of the switching unit windings, and a comparator, the output of which is connected directly to the second input of the switching node of the windings, and to the second input of the integrator through an electronic key. 1 ill.

Description

The invention relates to devices for recording and / or reproducing information with relative relative movement of the optical medium and the optical head and can be used in information technology, in particular in digital audio recording devices, in digital video recorders, in optical external storage devices.

The aim of the invention is to increase the accuracy and reliability of recording and / or reproducing information by stabilizing the instantaneous rotation speed of the optical information carrier.

The drawing shows a functional diagram of the inventive opto-mechanical storage device.

An optical-mechanical storage device includes an optically coupled optical information carrier 1 (disk, cylindrical, or other) and an optical pickup 2 (e.g., using a semiconductor laser), the septic output of which is coupled to a photodetector 3 (e.g., containing a photo diode, current transducer - voltage and comparator). The output of the photodetector assembly 3 is connected to the first input of the phase detector 4, to the second input of which a reference oscillation generator 5 is connected (for example, with quartz frequency stabilization). The output of the phase detector 4 through an integrator 6 (for example, based on an operational amplifier) is connected to the inputs of a comparator 7 (with a large hysteresis) and a pulse generator 8 with pulse-width modulation. The output of the 8 pulse generator with pulse width modulation is connected to the first

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to the node 9 of switching the windings (for example, based on a microcomputer), to the second input of which the output of the comparator 7 is connected. The output of the comparator 7 is also connected via the electronic key 10 to the second input of the integrator 6. Output (in fact, the number of outputs is equal to the number of switched windings) node 9 switching windings is connected to a stepper motor 11 (more precisely, to its windings).

The inventive optical-mechanical storage device operates as follows. When recording and reproducing information, the optical information carrier 1 rotates relative to the reading optical head 2. At the same time, the marks recorded on the optical information carrier 1 (in the service recording area, on reference tracks or other parts of the surface of the recording layer) modulate the optical radiation incident on the optical information carrier 1 . This radiation, reflected from the optical information carrier 1, is fed to the optical input of the photodetector 3, in which it is converted into electrical pulses, the repetition rate of which contains information about the instantaneous (with a certain approximation) speed of rotation of the optical information carrier 1. In a phase detector 4 to the input of which the signals read from the optical information carrier 1 and signals from the reference oscillation generator 5 are received, an error signal is generated, which is integrated by the integrator 6. Upon reaching certain fixed levels determined by the hysteresis of the comparator 7, this process is interrupted and starts again, since the output pulse of the comparator 7 opens the electronic switch 10, through which the capacitor of the integrator 6 is quickly discharged. Saw-like oscillations are formed at the output of the integrator 6, the repetition rate of which is proportional error signal at the output of the phase detector. These PWM pulses are fed to the winding switching unit 9, by which the windings of the stepper motor are switched in such a way that a smooth

rotor movement when switching windings. When the rotor of the stepper motor (not shown for simplicity in the drawing) completely passes the path between two adjacent windings, for the counting of the pulse supplied to the second input of the winding switching unit 9 from the output of the comparator 7, to the sequence of PWM pulses supplied to its first input, one more is added

pulse or one pulse excluded.

This ensures the transition to PWM switching of the next pair (or pairs) of adjacent

windings of a stepper motor 11.

Thus, in the inventive optomechanical storage device due to the frequency modulation of the sawtooth pulses at the output of the integrator, stabilization of the average rotation speed of the optical information carrier is ensured, and

Due to pulse-width modulation of the switching process of adjacent windings, the instantaneous rotation speed of the carrier is stabilized.

Claims (1)

The claims An optical-mechanical storage device containing an optically coupled optical information carrier and an optical pickup, the optical output of which is coupled to a photodetector connected to the first input of the phase detector, to the second input of which a reference oscillator is connected, as well as winding switching units connected in series and step a motor of rotation of the optical information carrier kinematically coupled to it, characterized in that, in order to increase the accuracy and reliability of recording and / or reproducing information, an integrator, an electronic key, a comparator, and a pulse-width-modulated pulse generator are introduced into it; moreover, the output of the phase detector through the integrator is connected to the inputs pulse generator with pulse-width modulation, the output of which is connected to the first input of the switching node of the windings, and a comparator, the output of which is connected to the second input of the switching node of the windings and the second input of the integrator through an electronic key.