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. 07, 1989
Filed:
Nov. 05, 1985
Makoto Yasuda, Kodaira, JP;
Tsune Miyashita, Tokyo, JP;
Seiichi Murayama, Kokubunji, JP;
Yoji Arai, Ome, JP;
Fuzio Yamada, Katsuta, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A high-pressure discharge lamp operating circuit performs a low-frequency AC operating at an early stage of operating and thereafter performs a high-frequency AC operation or DC operation during the steady-state of lamp operation. This circuit comprises a circuit for effecting a transition from the low-frequency AC operation to the high-frequency AC operation or DC operation either at the time which is a predetermined time period after the ignition of discharge before the high-pressure discharge lamp reaches the steady-state of operation, or after having detected at least one of predetermined lamp characteristics, thereby providing a stabilized light output.