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. 16, 1993
Filed:
Apr. 10, 1991
Hajime Shoji, Higashiosaka, JP;
Noriko Watanabe, Nara, JP;
Hiroshi Hamada, Nara, JP;
Hiroaki Kato, Nara, JP;
Toshio Takemoto, Nara, JP;
Toshihiko Hirobe, Sakai, JP;
Sharp Kabushiki Kaisha, Osaka, JP;
Abstract
A thin film semiconductor device and a liquid crystal display apparatus are provided wherein the thin film semiconductor device having light irradiated thereon is cut off by a conductor layer, and the ight can be prevented from reaching the semiconductor layer. As a result, the generation of carriers due to optical excitation does not occur and the off current can be reduced. Because there is no area where electric field intensity in an opposed direction to the source electrode and the drain electrode is weaker than the electric field intensity of the channel region in the semiconductor layer, even after an operation for a prolonged duration under the irradiation of light, carriers generated by optical excitation are not accumulated in the semiconductor layer, and the probability of trapping for the carriers into a gate insulating film is quite low, and therefore variations in the characteristics of the thin film semiconductor device are negligibly small. The liquid crystal display apparatus using the thin film semiconductor can restrict such deteriorations of display quality as the degradation of contrast and uniformity.