Patent US3625609A successfully refreshed from Google Patents.
US3625609A
Expired / Lapsed
US
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Combined focusing and probe device for photographic enlargers
Assignee: NORD PHOTO ENGINEERING Inc
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Filing: 1969-10-13
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Granted: 1971-12-07
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Expires: 1989-10-13
Abstract
Abstract A mirror is pivotable about an axis spaced a given distance from the plane in which the photosensitive paper is normally placed. The viewing screen of a focusing magnifier is placed an equivalent distance from the axis and also the light measuring probe aperture is likewise spaced an equivalent distance from said axis. In this way, any discrepancies attributable to the socalled inverse square law are automatically eliminated.
Inventors
- 👤 Roy A Clapp
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 23:05
CPC Classifications
G; G03; G03B; G03B3/00; G03B27/00; G03B27/72
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
153 words
A combined focusing and probe device for photographic enlargers comprising a support adapted to be positioned between the lens of an enlarger and the plane normally containing the photosensitive paper, a mirror mounted for pivotal movement about an axis parallel to said plane and spaced a given distance therefrom, viewing means having a surface for receiving reflected light from said enlarger lens when said mirror is in one pivotal position, and light measuring means having a surface for receiving said reflected light when said mirror is in a second pivotal position, said surfaces both being spaced from said axis at distances equaling said given distance. , 2. The device set forth in claim 1 in which said viewing means includes a tubular housing having a ground glass plate adjacent one end providing said first-mentioned surface and a magnifying lens adjacent the other end for magnifying the ray image appearing on said glass plate.
Claim 2
Dependent Claim
38 words
The device set forth in claim 2 in which said ground glass plate has a circular reticle centrally located thereon for enabling the selective viewing of a portion of a negative positioned with respect to said enlarger lens.
Claim 3
Dependent Claim
57 words
The device set forth in claim 3 in which said light measuring means includes a light conductive cable having one end thereof providing said second-mentioned surface for transmitting light and a photoelectric sensor disposed at the other end of said cable, said light conductive cable and sensor comprising a probe and said second-mentioned surface a probe aperture.
Claim 4
Dependent Claim
46 words
The device set forth in claim 4 in which the photographic enlarger includes an easel of magnetizable metal defining the plane normally containing said paper, said support means including a plurality of magnets for engaging said easel to releasably retain said support means on said easel.
Claim 5
Dependent Claim
132 words
A combined focusing and probe device for photographic enlargers comprising reflection means, means supporting said reflection means for pivotal movement about an axis spaced from the plane in which the photosensitive material normally is placed, means providing a first locus at which an image may be viewed, and means providing a second locus at which the light intensity of said image can be determined, said loci being spaced from said axis a distance equal to the distance said axis is spaced from said plane, whereby when said reflective means is in one pivotal position light from the enlarger is reflected via a first path to said first locus and when said reflective means is in second pivotal position light from said enlarger is reflected via a second path to said second locus.
Claim 6
Dependent Claim
132 words
A combined focusing and probe device for photographic enlargers comprising reflection means, means supporting said reflection means for pivotal movement about an axis spaced from the plane in which the photosensitive material normally is placed, means providing a first locus at which an image may be viewed, and means providing a second locus at which the light intensity of said image can be determined, said loci being spaced from said axis a distance equal to the distance said axis is spaced from said plane, whereby when said reflective means is in one pivotal position light from the enlarger is reflected via a first path to said first locus and when said reflective means is in second pivotal position light from said enlarger is reflected via a second path to said second locus.
Claim 7
Dependent Claim
33 words
The device set forth in claim 6 including an adjustment screw for determining said one pivotal position of said reflective means and a second adjustment screw for determining said second pivotal position thereof.
Claim 8
Dependent Claim
30 words
The device set forth in claim 7 in which said loci are individually adjustable with respect to said axis, and respective means for maintaining each locus in its adjusted position.
Claim 9
Independent Claim
111 words
A method of focusing and determining the proper amount of light in preparation for making a photographic enlargement from a negative comprising the steps of reflecting light passing through only a portion of the negative from a location spaced a given distance from the plane in which the photosensitive paper is later placed onto a viewing surface spaced the same distance from said location as said location is spaced from said plane, focusing the enlarger while viewing said surface, and then reflecting the same light passing through said portion onto light measuring means having a surface spaced the same distance from said location as said location is spaced from said plane.
Claim 10
Independent Claim
111 words
A method of focusing and determining the proper amount of light in preparation for making a photographic enlargement from a negative comprising the steps of reflecting light passing through only a portion of the negative from a location spaced a given distance from the plane in which the photosensitive paper is later placed onto a viewing surface spaced the same distance from said location as said location is spaced from said plane, focusing the enlarger while viewing said surface, and then reflecting the same light passing through said portion onto light measuring means having a surface spaced the same distance from said location as said location is spaced from said plane.
Claim 11
Dependent Claim
57 words
The method set forth in claim 9 including the additional step of shifting said location into various positions while spaced said given distance from the plane in which the photosensitive paper is later placed so that light is reflected from different portions of the negative until light from a preferred portion is reflected onto said viewing surface.
Claim 12
Dependent Claim
59 words
The method set forth in claim 10 in which the light is reflected by a reflective surface that is shiftable about an axis which constitutes said location so that light is reflected onto said viewing surface when said reflective surface is in one angular position and onto said surface of said light measuring means when in a second position.
Claim 13
Dependent Claim
17 words
The method set forth in claim 11 in which said reflective surface is provided by a mirror.
Claim 14
Dependent Claim
40 words
The method set forth in claim 12 including the step of removing the mirror after said viewing and light measuring steps have been completed so as to avoid any light obstruction when the photosensitive paper is placed in said plane.
References Cited (Backward Citations)
US2651969A
Cited
US3114283A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-12-06 | 1975-06-07 | 1975-12-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-12-06 | 1979-06-07 | 1979-12-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-12-06 | 1983-06-07 | 1983-12-07 | $7700.00 | Window Closed / Lapsed |