The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 03, 1998
Filed:
Nov. 22, 1996
Taizo Takiguchi, Tokyo, JP;
Sony Corporation, Tokyo, JP;
Abstract
In an optical recording apparatus which records data by stabilizing the duration of laser beam emission, a controller produces a clock signal which is synchronous to source data to be recorded, and modulates the data into modulated data. A phase comparator, oscillator and frequency demultiplier produce a signal which is synchronous to the modulated data, has a constant duty-cycle and has a period that is 1/Kb time (Kb is an integer greater than or equal to 2) the data period of the shortest modulated data. Based on the data and signal, laser emission pattern signals are produced. Signal generators produce reference signals in response to control signals from a microcomputer. Switches are controlled by the pattern signals to conduct reference signals selectively. A laser diode is driven by a signal which is the sum of the selected reference signals, and the laser power is controlled accordingly. The constant duty-cycle of the signal prevents the fluctuation of the duration of laser beam emission.