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:
Jul. 04, 2000
Filed:
Oct. 13, 1998
Seiichi Yasukawa, Chiba, JP;
Nikon Corporation, Tokyo, JP;
Abstract
Apparatus and method for regulating and controlling the amount of light emitted by a flash unit for use with an imaging device. The apparatus and method include and involve a light source configured to illuminate a subject to imaged by an imaging device, a light receiving element configured to receive light emitted by the light source and reflected by the subject, and to generate a signal based on the reflected light, a light amount determination unit coupled to the light receiving element and configured to determine an amount of reflected light received by the light receiving element based on the signal, a light amount comparison unit coupled to the light amount determination unit and configured to compare the amount of reflected light determined by the light amount determination unit with a threshold value to generate a corresponding control signal, and a light source regulator coupled to the light amount comparison unit. The light source regulator includes a range detector configured to detect a distance to the subject, and a guide number setting unit configured to calculate at least one guide number based on that distance and an operating parameter related to the imaging device. The calculated guide number(s) correspond to an amount of time light is to be emitted by the light source during an imaging operation. The light source regulator controls the emission of light by the light source based on the control signal and the calculated guide number(s).