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US3709591A Expired / Lapsed US ⏱️ 0.0 years remaining

Variable photographic mask for maintaining multiple constant proportions of a visible area

Assignee: Individual
•
Filing: 1971-07-26
•
Granted: 1973-01-09
•
Expires: 1991-07-26
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Abstract

Abstract A mask for demarcating a selected portion of a photograph according to constant proportions of an aperture of the mask for use in making reproductions or projections, usually enlargements, of the selected portion. The mask includes a sheath which guides a slide through two opposite open ends of the sheath. A substantially rectangular aperture passes through the sheath and slide. Two diagonally opposite corners of the aperture are located on coincident centerlines of the sheath and slide and two aperture sides forming one of the corners are of a different proportion then the opposing two aperture sides forming the other corner. The slide aperture so formed is rotated 180* within the sheath to locate identically proportioned sides of the sheath and slide opposite each other on the coincident centerlines. In operation, the aperture is placed over the selected portion of a photograph and the particular proportion of the selected area is chosen by adjusting the area of the aperture by adjusting the position of the slide. The desired size is marked on the photograph by outlining the aperture. If the other proportion is desired instead, then the slide is adjusted in the opposite direction to adjust the area of the aperture.

Inventors

  • 👤 W Alzmann

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 07:49
CPC Classifications
G; G03; G03B; G03B27/00; G03B27/32; G03B27/52; G03B27/62

Claims Analysis

Total Claims: 3
Claim 1
Independent Claim 128 words
An apertured unit for demarcating a selected portion of a photograph or the like, which comprises: a sheath having two opposite open ends and a centerline intersecting the open ends; and a slide located within the sheath and of a size and shape complementary to that of the sheath, said slide having a centerline coincident to the sheath centerline and adapted to slide within the sheath while maintaining coincident centerlines, said sheath and slide having an aperture therethrough with two diagonally opposite corners located on the centerlines, two aperture sides forming one corner being of a different ratio of length than the two aperture sIdes forming the other corner, the slide aperture so defined being rotated through 180 degrees upon the sheath centerline for location within the sheath.
Claim 2
Dependent Claim 128 words
An apertured unit for demarcating a selected portion of a photograph or the like, which comprises: a sheath having two opposite open ends and a centerline intersecting the open ends; and a slide located within the sheath and of a size and shape complementary to that of the sheath, said slide having a centerline coincident to the sheath centerline and adapted to slide within the sheath while maintaining coincident centerlines, said sheath and slide having an aperture therethrough with two diagonally opposite corners located on the centerlines, two aperture sides forming one corner being of a different ratio of length than the two aperture sIdes forming the other corner, the slide aperture so defined being rotated through 180 degrees upon the sheath centerline for location within the sheath.
Claim 3
Dependent Claim 18 words
An apertured unit as recited in claim 1 wherein the sheath and slide are of a plastic material.

References Cited (Backward Citations)

US2246920A Cited
US2702944A Cited
US3203334A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1976-01-09 1976-07-10 1977-01-09 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1980-01-09 1980-07-10 1981-01-09 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1984-01-09 1984-07-10 1985-01-09 $7700.00 Window Closed / Lapsed

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