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. 19, 2005
Filed:
Sep. 27, 2002
Aoji Isono, Kanagawa, JP;
Tadashi Aoki, Kanagawa, JP;
Kazuhiko Murayama, Kanagawa, JP;
Kenji Shino, Kanagawa, JP;
Tsutomu Sakamoto, Saitama, JP;
Aoji Isono, Kanagawa, JP;
Tadashi Aoki, Kanagawa, JP;
Kazuhiko Murayama, Kanagawa, JP;
Kenji Shino, Kanagawa, JP;
Tsutomu Sakamoto, Saitama, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Kabushiki Kaisha Toshiba, Tokyo, JP;
Abstract
A drive signal generation circuit which performs gradation control on a load by a drive signal having a stepped waveform. In a case where the wave height value corresponding to input gradation data is Vm (2≦m≦n), the drive signal is caused to rise in such a manner that each output Vk (2≦k≦m) is produced one slot after the output V(k−1) to increase the wave height value V(reference potential) to Vm in a stepping manner. One slot corresponds to a unit time of the pulse width modulation. The drive signal is caused to fall in such a manner that each output V(k−1) (1≦k≦m−1) is produced one or two slots after the output Vk to reduce the wave height value from Vm to off level in a stepping manner. A delay circuit is used to delay signals slot by slot. A selection is made from delayed signals according to luminance data to determine a waveform. The circuit is also designed to enable the drive signal waveform rise position to be changed.