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:
Mar. 10, 2009
Filed:
Jan. 31, 2005
Osamu Yuki, Tokyo, JP;
Yoshinori Nakajima, Yokohama, JP;
Shigeki Kondo, Hiratsuka, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A drive circuit including a drive transistor for feeding to a load a drive current corresponding to an input signal. The drive circuit has a correction circuit that supplies a correction signal corresponding to an impedance of the load to a gate of the drive transistor to correct the drive current to be fed to the load by the drive transistor, and in which the load is a light-emitting element. One terminal of the light-emitting element is connected to a gate of a transistor for correction, and when a predetermined potential Ps is set to a value calculated by deducting a threshold voltage Vth of the transistor for correction from a terminal potential Pi of the light-emitting element with respect to a drive current, the drive circuit sets a source potential of the transistor for correction to the predetermined potential Ps to thereby generate a voltage corresponding to an impedance of the light-emitting element as a source-to-drain current of the transistor for correction.