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:
Oct. 06, 1981
Filed:
May. 19, 1980
Dainippon Screen Seizo Kabushiki Kaisha, Kyoto, JP;
Abstract
A photographic film blackened area measuring device, having two rod shaped light conducting members, each of which is formed as an elongated piece of transparent material with part of its surface, parallel to its axis, being roughened so as to diffuse light, while light is totally internally reflected along the length of the rod shaped member from the remainder of its smooth surface. These rod shaped light conducting members are arranged one on each side of a piece of developed photographic film in a automatic film developing machine, and the film passes between them. A light emitting device is provided at one end of one of the rod shaped light conducting members, and a photo sensitive device is provided at the end of the other rod shaped light conducting member which is remote from the light emitting device. Thereby, as the photographic film moves between the rods, fluctuations of the output of the light sensitive device are produced, depending on the total area of blackening of the photographic film, but substantially independent of the positioning and arrangement of said blackened area with respect to the edges of the film.