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. 05, 2002
Filed:
Feb. 25, 2000
Makoto Isozaki, Tokyo, JP;
Junichi Takagi, Kanagawa, JP;
Kazumi Koike, Kanagawa, JP;
Mitsuhiro Moriya, Kanagawa, JP;
Keiji Uchiyama, Kanagawa, JP;
Yukitsugu Hata, Kanagawa, JP;
Fuji Photo Film Co., Ltd., Kanagawa, JP;
Abstract
In a flash circuit of a flash device, a Zener diode ( ) is connected to a tap point ( ) located at an intermediate position of a secondary coil of an oscillation transformer ( ). The oscillation transformer ( ) and an oscillation transistor ( ) constitutes an oscillation circuit. A potential at the tap point ( ) changes proportionally to a voltage charged in a main capacitor ( ). When the main capacitor ( ) is charged up to a set voltage, the Zener diode ( ) conducts a Zener current, which activates a stopping transistor ( ) and thus deactivates the oscillation circuit. When a flash charge switch ( ) is turned on, an end of a light guide portion of a charge condition indicator ( ) protrudes out of a lens-fitted film unit. When the main capacitor ( ) is charged up to the set voltage, a light emission element starts lighting, and the light from the light emission element is projected from the end of the light guide portion.