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US3947112A Expired / Lapsed US ⏱️ 0.0 years remaining

Device for document filming

Assignee: Pentacon GmbH Foto und Feinwerktechnik
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Filing: 1974-06-24
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Granted: 1976-03-30
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Expires: 1994-06-24
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Abstract

Abstract A document photographing device has a surface for supporting a document to be photographed, a camera positioned about the surface, to receive light reflected from and transmitted by a document supported on the surface, and separate means for illuminating the document from above and below respectively. An exposure meter receives light reflected from or transmitted through the document and indicates when correct exposure conditions have been set. The exposure meter includes correction means for correcting the reading of the exposure meter to take account of the different spectral radiation characteristics of the illuminating means.

Inventors

  • 👤 Erich Hahn
  • 👤 Frank Reissig

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-31 06:21
CPC Classifications
G; G01; G01J; G01J1/00; G01J1/42; G01J1/4209; G01J1/4223

Claims Analysis

Total Claims: 10
Claim 1
Independent Claim 146 words
A device for photographing documents comprising: i. a surface for supporting a document to be photographed; ii. a camera positioned above said surface, to receive light reflected from and transmitted by a document when supported on said surface; iii. first illumination means for illuminating from above a document when supported on said surface; iv. second illuminating means for illuminating from below a document when supported on said surface, having spectral radiation characteristics different from said first illuminating means; v. means for selecting between illumination from above and from below; vi. an exposure measuring device for receiving light reflected from or transmitted through a document when supported on said surface, and for indicating when correct exposure conditions have been set; vii. correction means for correcting the reading of the exposure meter to take account of said different spectral radiation characteristics of the first and second illuminating means.
Claim 2
Independent Claim 146 words
A device for photographing documents comprising: i. a surface for supporting a document to be photographed; ii. a camera positioned above said surface, to receive light reflected from and transmitted by a document when supported on said surface; iii. first illumination means for illuminating from above a document when supported on said surface; iv. second illuminating means for illuminating from below a document when supported on said surface, having spectral radiation characteristics different from said first illuminating means; v. means for selecting between illumination from above and from below; vi. an exposure measuring device for receiving light reflected from or transmitted through a document when supported on said surface, and for indicating when correct exposure conditions have been set; vii. correction means for correcting the reading of the exposure meter to take account of said different spectral radiation characteristics of the first and second illuminating means.
Claim 3
Dependent Claim 85 words
Device according to claim 1, wherein said exposure measuring device includes a measuring circuit, and said correction device comprises a damping resistor arranged in the measuring circuit, the electric value of which damping resistor corresponds to the electric value of the measurement difference caused by said different spectral radiation characteristics and which damping resistor can be connected and disconnected by a switch lying electrically in parallel with the damping resistor and to be operated in the change between said illumination from above and from below.
Claim 4
Dependent Claim 15 words
Device according to claim 2, wherein the damping resistor is formed as a variable resistor.
Claim 5
Dependent Claim 44 words
Device according to claim 3, wherein said means for selecting between illumination from above and from below includes a switch having a part which cooperates with the switch for connecting and disconnecting the damping resistor upon changing between illumination from above and from below.
Claim 6
Dependent Claim 54 words
Device according to claim 1, wherein said exposure measuring device includes a measuring circuit having a rheostat for the introduction of different film sensitivities, the rheostat having a slider, a scale attached to said slider and a setting mark against which said scale is settable, the scale having indications indicative of different film sensitivities.
Claim 7
Dependent Claim 70 words
Device according to claim 5, wherein the rheostat is displaceable relative to the slider and said means for selecting between illumination from above and from below includes a switch having a switch cam which cooperates with said displaceable rheostat to displace the latter upon changing between illumination from above and below, this relative displacement corresponding to the electric value of the measurement difference caused by said different spectral radiation characteristics.
Claim 8
Dependent Claim 48 words
Device according to claim 5, wherein the setting mark is arranged on a movably mounted plate which is movable upon changing between illumination from above and below, the range of this movement corresponding to the electric value of the measurement difference caused by said different spectral radiation characteristics.
Claim 9
Dependent Claim 43 words
Device according to claim 7, wherein said means for selecting between illumination from above and from below includes a switch having a part which cooperates with said movably mounted plate to move the latter upon changing between illumination from above and from below.
Claim 10
Dependent Claim 87 words
Device according to claim 5, wherein the measuring circuit includes a current meter having a pointer which swings in relation to two measuring marks, alignment of the pointer with one of said marks being indicative of correct exposure settings when illumination from above is used, alignment of the pointer with the other of said marks being indicative of correct exposure when illumination from below is used, the distance between said marks corresponding to the electric value of the measurement difference caused by said different spectral radiation characteristics.

References Cited (Backward Citations)

US2201606A Cited
US2472381A Cited
US2857555A Cited
CH386847A Cited
US3402636A Cited
US3606552A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1979-03-30 1979-09-29 1980-03-30 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1983-03-30 1983-09-29 1984-03-30 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1987-03-30 1987-09-29 1988-03-30 $7700.00 Window Closed / Lapsed

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