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:
Apr. 03, 1984
Filed:
Dec. 31, 1981
Nicholas Mischenko, Mount Prospect, IL (US);
Robert R Parker, Wheeling, IL (US);
Rudolph Starai, Arlington Heights, IL (US);
Bell & Howell Company, Chicago, IL (US);
Abstract
A slide tray position sensing arrangement is provided for slide projector apparatus. The slide tray position sensing arrangement is arranged at a detection station. A coded aperture ring is provided that moves in a manner correlated to the movement of a slide tray turntable. The slide tray turntable carries the slide tray that holds the slides for projection and also functions as a tray transport arrangement. The coded aperture ring includes two circumferential arrays of apertures. Each of the apertures in the first array corresponds to a controlled slide position of a first tray type; e.g., an 80 slide tray. Each of the apertures in the second array corresponds to a controlled side position of a second tray type; e.g., a 140 slide tray. The slide tray position sensing arrangement is controllable to selectively sense the appropriate array of apertures corresponding to the slide tray type being utilized. In a first arrangement, the position sensing arrangement is selectively movable between two detection positions; each of the detection positions being aligned with a respective one of the aperture arrays. In a second arrangement, two detection arrangements are provided; each of the detection arrangements being aligned with a respective one of the aperture arrays.