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:
Nov. 13, 2001
Filed:
Mar. 23, 2000
Fuji Photo Film Co., Ltd., Kanagawa, JP;
Abstract
An electronic flash device equipped with LED indicator for providing an indication of completion of charging a main capacitor and a circuit for lowering power consumption has a controlling transistor operative to control a base current of the oscillating transistor which increases or decreases a primary current flowing through a primary winding and to be turned conductive by a current supplied from a battery through a current limiting resistor to start supply of the base current of the oscillating transistor. A secondary current generated in a secondary winding increases the base current of the controlling transistor, which increases the base current of the oscillating transistor which is lowered by the current limiting resistor having a large resistance and is increased or decreased by the controlling transistor. The electronic flash device can lower the power consumption as compared to the conventional devices which use a tertiary winding to increase or decrease the base current of the oscillating transistor. A tertiary winding of the electronic flash device is solely used for turning on LED.