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:
Sep. 21, 1976
Filed:
Dec. 16, 1974
Frank W Betlejewski, Elgin, IL (US);
Bell & Howell Company, Chicago, IL (US);
Abstract
An electronic flash unit for use with a camera having a manually adjustable aperture lens. The flash unit includes an exposure calculator which uses the principle of triangulation for automatically calculating the correct F stop setting for the adjustable lens. A pendulous indicator is pivotally mounted within the flash unit so as to be adjustable due to gravitational forces when the unit is aligned with the base of the subject through a sighting device on the side of the housing. The indicator is lockable in the adjusted position to indicate the appropriate aperture setting on an F stop scale. The F stop scale also is rotatably mounted on the flash unit to permit the user to rotate the scale to accommodate for the use of various films. The F stop scale is preset according to an ASA film number for the particular speed of the film being used. A stationary foot or centimeter scale also is provided to indicate the position of the subject relative to the camera in feet or centimeter dimensions. An auxiliary light is provided on the flash unit for aiding in visually aligning the flash unit under subdued light conditions.