US3829210A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Illuminating system of an enlarger
Assignee: Meopta np
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Filing: 1972-12-07
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Granted: 1974-08-13
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Expires: 1992-12-07
Abstract
Abstract Illuminating system for a photographic enlarger for making color reproductions, consisting of a projection lamp with a spherical or an aspherical reflection mirror and of an enclosure for mixing colored light. The enclosure is provided with an input and an output ground glass window, between which a system of movable color correction filter is arranged. Between the projection lamp and the input window there is placed a dispersive optical assembly consisting of a system of optical prisms, whose optical axes are parallel with the axis of the illuminating system and perpendicular to the direction of movement of the color correction filters. The prisms are paired equidistant from the axis of the optical system, each pair having the same refractive power. A single prism is also provided, lying on the axis of the optical system, having a zero refractive power.
Inventors
- 👤 V Langer
- 👤 E Nesvadba
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 20:25
CPC Classifications
G; G03; G03B; G03B27/00; G03B27/72; G03B27/73
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
124 words
Apparatus for illuminating the object image in a color photoenlarger comprising a source of light, a first ground glass aligned along the optical axis of said source for receiving said light to illuminate said image, a lens assembly interposed between said source and said grouNd glass, said lens assembly comprising a lens member lying along said optical axis and a plurality of optical wedges arranged in pairs symmetrical to the optical axis, the wedges in each pair having the same refractive power and lying equidistant from the optical axis, for dispersing said light source into a plurality of images incident upon said ground glass, and filter means movable between said lens assembly and said ground glass for selectively modifying the color of said images.
Claim 2
Dependent Claim
124 words
Apparatus for illuminating the object image in a color photoenlarger comprising a source of light, a first ground glass aligned along the optical axis of said source for receiving said light to illuminate said image, a lens assembly interposed between said source and said grouNd glass, said lens assembly comprising a lens member lying along said optical axis and a plurality of optical wedges arranged in pairs symmetrical to the optical axis, the wedges in each pair having the same refractive power and lying equidistant from the optical axis, for dispersing said light source into a plurality of images incident upon said ground glass, and filter means movable between said lens assembly and said ground glass for selectively modifying the color of said images.
Claim 3
Dependent Claim
20 words
The apparatus according to claim 1 including a second ground glass arranged between the lens assembly and the filter means.
Claim 4
Dependent Claim
65 words
The apparatus according to claim 2 including a rectangular enclosure housing said filter means, the first and second ground glasses comprising the ends of said enclosure and forming input and output windows for said light source, said filter means being mounted to be selectively movable into and out of said enclosure in a plane parallel to said ground glasses and perpendicular to the optical axis.
Claim 5
Dependent Claim
49 words
The apparatus according to claim 1 wherein the number of optical wedges in said lens assembly is determined by the relation S m/v - 1 where: S the number of prisms, m height of the first diffusion plate, and v the height of the filament of the projection lamp.
Claim 6
Dependent Claim
25 words
The apparatus according to claim 4 wherein the lens member at the center of the lens assembly is a plane glass with zero refractive power.
Claim 7
Dependent Claim
20 words
The apparatus according to claim 1 wherein the filter means comprises a plurality of filters selected for subtractive color values.
Claim 8
Dependent Claim
20 words
The apparatus according to claim 1 wherein the filter means comprises a plurality of filters selected for additive color values.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-08-12 | 1978-02-11 | 1978-08-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-08-12 | 1982-02-11 | 1982-08-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-08-12 | 1986-02-11 | 1986-08-13 | $7700.00 | Window Closed / Lapsed |