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:
Apr. 24, 2012
Filed:
Dec. 21, 2006
Masaki Noda, Tokyo, JP;
Masamichi Nogami, Tokyo, JP;
Junichi Nakagawa, Tokyo, JP;
Mitsubishi Electric Corporation, Tokyo, JP;
Abstract
An optical receiver of wide-dynamic range characteristic that stably reproduces a burst signal having different light receiving levels. A preamplifier converts an output from a light receiving element into a voltage signal. A level detecting circuit includes: a first level detecting unit having a shorter time constant; and a second level detecting unit having a longer time constant and switching over to any of the level detecting units in response to a time constant switching signal to detect a voltage level of an output voltage signal output from the preamplifier. An amplifier variably controls conversion gain of the preamplifier based on the detecting result. A time constant switching control outputs the time constant switching signal to the level detecting unit based on the output voltage signal from the preamplifier, to select the first level detecting unit or the second detecting unit based on a number of consecutive identical digits being equal to, smaller, or larger than the predetermined number.