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. 21, 1989
Filed:
Apr. 14, 1988
Katsumi Nagano, Setagaya, JP;
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Abstract
A laser diode circuit has a photodiode which monitors the light output which is outputted by the laser diode and generates a photovoltaic current that corresponds to the level of the light output, a reference current selection device which selects a required reference current by switching among a plurality of reference current sources that are set to values of mutually different current values, and an amplifying apparatus which, by receiving a signal that corresponds to the photovoltaic current, controls the forward current of the laser diode so as to bring the photovoltaic current to a selected reference current. Instead of the above construction, there may be employed a construction which has a voltage transforming selector which generates a photovoltaic current signal voltage that corresponds to the photovoltaic current, a reference voltage selection device which selects a required reference voltage by switching among a plurality of reference voltage sources that are set to values of mutually different reference voltages, and an amplifying apparatus which, by receiving the photovoltaic current signal voltage and a selected reference voltage, controls the forward current of the laser diode so as to bring the photovoltaic current signal voltage equal to the selected reference voltage.