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. 29, 1997
Filed:
Sep. 01, 1995
Seiichi Yasukawa, Yotsukaido, JP;
Nikon Corporation, Tokyo, JP;
Abstract
A low cost, compact multi-light through-the-lens adjustment unit for use in a camera which incorporates a built-in flash allowing an increase in the speed of a shutter release operation of the camera. A charged voltage of a charge accumulation unit is measured prior to a light pre-emission. The light pre-emission is initiated and thereafter terminated based on a quantity of reflected light detected. The time difference between the initiation of the light pre-emission and the termination of the light pre-emission is measured by a time difference measurement unit. The amount of light pre-emission light of the light emission unit is calculated based on the measured charged voltage and the time difference measurement. Alternatively, the charged voltage prior to light pre-emission is measured by a first voltage measurement unit and the charging voltage after light pre-emission is measured by a second voltage measurement unit. The amount of light pre-emission is calculated based on the difference between charged voltage prior to the light pre-emission and charging voltage after the light pre-emission.