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.

Date of Patent:
Oct. 14, 2003

Filed:

Sep. 21, 2001
Applicant:
Inventor:

Katsumi Motomura, Saitama, JP;

Assignee:
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G03B 1/505 ;
U.S. Cl.
CPC ...
G03B 1/505 ;
Abstract

In a lens-fitted photo film unit, a flash device has a booster circuit including primary and secondary windings, the secondary winding generating high voltage when power source voltage is applied to the primary winding. A main capacitor is charged by the high voltage in the secondary winding. A flash discharge tube is connected in parallel with the main capacitor, for emitting flash light upon discharge with electric energy from the main capacitor. A trigger circuit discharges the flash discharge tube upon a switching operation. A photo transistor measures reflected light from an object illuminated by the flash light, to output a light amount signal. A light amount control circuit quenches discharge of the flash discharge tube when an integration value of the light amount signal comes up to a predetermined value. A powering voltage generator circuit is connected with the secondary winding, for generating powering voltage adapted for powering the light amount control circuit in response to operation of the trigger circuit.


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