Invalidity dossier
US 4360264
Variable magnification slide copy camera
Current assignee: Polaroid Corp
Added 9/23/2026, 11:29:56 PM
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Patent summary
Title, assignee, inventors, filing/issue dates, abstract, and a plain-language overview of the claims.
Patent Overview — US4360264A
Title: Variable magnification slide copy camera
Patent number: US4360264A
Application number: US06/288,820
Inventors: Philip G. Baker; Gerald L. Matthews
Original/current assignee (as listed): Polaroid Corp
Priority date / filing date: 1981-07-31
Publication (grant) date: 1982-11-23
Legal status (as listed): Expired – Lifetime; anticipated expiration 2001-07-31
Purpose: The patent relates to photography and, more specifically, to a photographic copy apparatus or camera for previewing an original picture to be copied (e.g., a 35 mm slide transparency) and projecting an enlarged image of it onto a film unit for exposure.
Plain-language scope: The apparatus operates in at least two magnification modes to selectively vary the size of a projected image. It uses a fixed-focus lens mounted at a fixed position between alternative pairs of image and object positions, reducing cost relative to interchangeable or zoom lenses. A light-tight cassette holding the photosensitive sheet is inserted into one of two slots in the housing, placing the film at either a first or second film plane spaced at different fixed image distances from the lens. First and second object planes are selected so a slide at the first object plane focuses at the first image plane at a first magnification, and a slide at the second object plane focuses at the second image plane at a second, different magnification. In the described embodiment, the camera makes full-frame or cropped reproductions of a 35 mm slide on an 8×10 film unit (e.g., 7.3× full frame via the forward slot, 9× cropped via the rear slot). An exposure control system controls image-forming light transmission and is automatically adjusted for the selected mode. A blocking arrangement prevents cassette insertion into the wrong slot; slide holders move alternately into the projection path; an illuminated preview window indicates correct slide placement; and an interlock disenables the exposure control system if the slide is misplaced or the holder is not correctly positioned.
Source: https://patents.google.com/patent/[US4360264](/patent/US4360264)/en
What the excerpt does not establish: The full text of the claims and their exact scope; the complete specification and all drawing details; the full contents of the prior-art discussion; and any findings on validity, infringement, or litigation. Assignments, security interests, and bankruptcy-related releases appearing in the record are not analyzed here.
Generated 10/1/2026, 9:32:41 PM
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Litigation summary
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Proceedings on file (0)
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PTAB challenges
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Assignment history
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Prior art
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Obviousness
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Extensions
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Derivative works
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