US3907427A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Lighting attachment for photographic enlargers
Assignee: Individual
•
Filing: 1974-01-11
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Granted: 1975-09-23
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Expires: 1994-01-11
Abstract
Abstract A lighting attachment for photographic enlargers having a light source for projecting an illuminated beam through a negative including a highly reflective double cone having its conical axis directed toward the light source, a semi-spherical hollow ball having a white internal wall surface surrounding said double cone and having an input opening on its curved surface between the cone and the light source and a light output opening disposed on the open flat portion of the ball, a diffusion disk closing the output opening of the ball for diffusing the light source and, a strip reflector disposed in the path of the light beam and having a surface for adjusting the reflection of the light before the light enters the photographic nagative. Variable filters are also provided for changing the color of the light reaching the negative.
Inventors
- 👤 Werner Tschink
- 👤 Rudolf Beger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 11:36
CPC Classifications
G; G03; G03B; G03B27/00; G03B27/72
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
181 words
A lighting attachment for photographic enlarging devices for enlarging negatives comprising: a light source for projecting an illuminated beam; a semi-spherical hollow ball having a white internal wall surface with an input opening on its curved surface directed at said light source, and a light output opening disposed on the open flat portion of the ball opposite said input opening, said openings defining the optical axis of the ball; a highly reflective double cone centrally disposed within said hollow ball and consisting of two cones having common bases with their vertexes defining an axis that is coaxial with the optical axis of said ball, wherein one cone reflects light from said light source onto the internal wall surface of said ball, and the other cone reflects light from the wall surface to the output opening; a diffusion disk closing the output opening of the ball for diffusing the reflected light; and a strip reflector disposed in the path of the light, said strip reflector having a surface for adjusting the reflection of the light before the light enters the photographic negative.
Claim 2
Dependent Claim
181 words
A lighting attachment for photographic enlarging devices for enlarging negatives comprising: a light source for projecting an illuminated beam; a semi-spherical hollow ball having a white internal wall surface with an input opening on its curved surface directed at said light source, and a light output opening disposed on the open flat portion of the ball opposite said input opening, said openings defining the optical axis of the ball; a highly reflective double cone centrally disposed within said hollow ball and consisting of two cones having common bases with their vertexes defining an axis that is coaxial with the optical axis of said ball, wherein one cone reflects light from said light source onto the internal wall surface of said ball, and the other cone reflects light from the wall surface to the output opening; a diffusion disk closing the output opening of the ball for diffusing the reflected light; and a strip reflector disposed in the path of the light, said strip reflector having a surface for adjusting the reflection of the light before the light enters the photographic negative.
Claim 3
Dependent Claim
30 words
The lighting attachment as recited in claim 1 additionally comprising an ellipsoidal reflector disposed at the light output of said strip reflector for directing the light to the photographic negative.
Claim 4
Dependent Claim
165 words
The lighting attachment as recited in claim 1 wherein said strip reflector comprises a reflective surface, two spaced apart parallel stationary walls mounted adjacent to said reflective surface and having shaft receiving apertures, a plate disposed between the stationary walls having corresponding shaft openings, said plate being spring supported between said walls, a plurality of shafts slidably disposed and guided through the shaft openings of said plate, said shafts including slides for projecting through the reflective surface, an elastic lining disposed in the shaft openings of said plate and frictionally engaging said shafts, a bell crank drive coupled to said plate and secured to said walls for displacing said plate with respect to said walls so that in one operating position of said plate, said shafts can be freely adjusted while in the other operating position the shafts are held in a fixed position by the elastic lining which exerts a one-sided pressure on the shafts when the plate is displAced by the bell crank.
Claim 5
Dependent Claim
92 words
The lighting attachment as recited in claim 3 wherein said strip reflector additionally comprises a retractor plate mounted adjacent to one of said parallel stationary walls and having apertures for slidably receiving said shafts and wherein said shafts comprise shaft heads larger than the apertures of said retractor plate, said retractor plate being freely displaceable in the direction of said shafts so that said retractor plate when displaced, engages said shaft heads to return all of said shafts to a fully retracted position with respect to the surface of said strip reflector.
Claim 6
Dependent Claim
31 words
The lighting attachment as recited in claim 4 wherein the elastic lining of said plate comprises a plastic material tightly encompassing all of said shafts when said bell crank is actuated.
Claim 7
Dependent Claim
101 words
The lighting attachment as recited in claim 5 comprising (reproducable) storage means for reproducing the various operating positions of the slides, having a housing, a storage plate held in suspension by springs within said housing, said storage plate including flush bearing apertures corresponding to the exact location of the apertures of said shafts, a plurality of sliders slidably disposed in the apertures of said plate and an arresting plate disposed in said housing for securing each of said sliders in a fixed position corresponding to a predetermined displacement of said shafts so that the location of said shafts can be determined.
Claim 8
Dependent Claim
16 words
The lighting attachment as recited in claim 4 wherein the shaft heads are constructed of iron.
Claim 9
Dependent Claim
88 words
The lighting attachment as recited in claim 7 wherein said strip reflector additionally comprises a cylindrical jacket which is open on its front face, a bar magnet displaceably mounted in said jacket and an arched spring coupled to said jacket and said bar magnet for displaceably moving said bar magnet within said jacket so that when the bar magnet contacts the iron head of said shaft, said shaft can be adjusted and when the bar magnet is retracted within said cylindrical jacket, said magnet disengages the shaft head.
Claim 10
Dependent Claim
84 words
The lighting attachment as recited in claim 1 additionally comprising filter means mounted between the light source and the input opening of said semi-spherical ball, said filter means having at least one pair of carriers spaced apart with respect to each other and movable toward each other, at least one filter mounted on each of said carriers so that opposed edges of said filters overlap once the carriers are moved toward each other across the path of the light beam from the light source.
Claim 11
Dependent Claim
26 words
The lighting attachment as recited in claim 9 wherein said carriers include an endless pull cable coupled to each of said carriers for displacing the carriers.
Claim 12
Dependent Claim
36 words
The lighting attachment as recited in claim 10 wherein said carriers support three pairs of dichroitic filters in three subtractive base colors so that said filters can be displaced to overlap with respect to each other.
Claim 13
Dependent Claim
75 words
The lighting attachment as recited in claim 1 comprising filter means with color filters disposed between the light source and the input opening of the semi-spherical ball having a plurality of pairs of pivotable carriers for supporting pairs of color filters respectively, said carriers moving relative with respect to each other to provide complete overlapping color filters so that the opposite edges of the filters move in a non-parallel path with respect to each other.
Claim 14
Dependent Claim
65 words
The lighting attachment as recited in claim 12 wherein said pivotable carriers additionally comprise springs urging said carriers toward each other so that said filters will overlap, a cam disk engaging said pivotable carriers for separating the carriers and their filters against the force of said springs and a lever drive coupled to said cam disk for rotating said cam disk to adjust said filters.
Claim 15
Dependent Claim
24 words
The lighting attachment as recited in claim 12 additionally comprising a rail engaging and guiding the free end of each of said pivotable carriers.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-09-22 | 1979-03-24 | 1979-09-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-09-22 | 1983-03-24 | 1983-09-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-09-22 | 1987-03-24 | 1987-09-23 | $7700.00 | Window Closed / Lapsed |