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:
Nov. 26, 2002
Filed:
Jan. 25, 2000
Masaaki Kurebayashi, Ebina, JP;
Akihiro Asada, Chigasaki, JP;
Toshimitsu Kaku, Sagamihara, JP;
Hideo Oonuki, Yokohama, JP;
Takashi Hoshino, Yokohama, JP;
Hidehiko Kandou, Matsudo, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A laser drive (LD) unit according to the present invention is provided with a laser drive waveform controller into which information for setting the laser drive is entered from a controller for generating a laser drive waveform on the basis of that information and supplying an indicated amperage; an LD current setting unit for setting a laser drive current matching the indicated amperage; an LD current output unit for varying the laser drive current on the basis of the laser drive waveform and supplying the current so varied to a laser diode and a current setting corrector into which a monitor signal obtained at the time of monitoring the laser beam emission from the laser diode is monitored, for correcting the laser drive current set by the current setting unit by using that monitor signal to adjust the power of the laser diode The laser drive waveform controller current setting unit current output unit and current setting corrector are formed on the same substrate.