← Back to Patent Explorer
US4729015A Expired / Lapsed US ⏱️ 0.0 years remaining

Method and apparatus for making positive copies from diapositives

Assignee: AgfaPhoto GmbH
•
Filing: 1986-07-09
•
Granted: 1988-03-01
•
Expires: 2006-07-09
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract Diapositives are copied on negative photosensitive paper in an apparatus wherein the positive is electronically scanned, line-by-line, and the thus obtained density signals are electronically inverted prior to influencing the beam of a CRT or laser which is used to reproduce the image of the positive on paper, either line-by-line or point-by-point. The inversion of signals renders it possible to scan the high-transmissivity portions of the positives with a narrow beam, i.e., with a high degree of resolution.

Inventors

  • 👤 Eduard Wagensonner

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 04:52
CPC Classifications
H; H04; H04N; H04N1/00; H04N1/40; H04N1/401; H04N1/23; H04N1/46; H04N1/50; H04N1/506; H04N1/508

Claims Analysis

Total Claims: 21
Claim 1
Independent Claim 53 words
A method of making a copy of an original, particularly a positive copy of a diapositive, comprising the steps of photoelectrically scanning the original, line-by-line, to obtain density signals; electronically inverting the density signals; directing a beam of radiation against a negative photosensitive material; and influencing the beam by the inverted density signals.
Claim 2
Independent Claim 53 words
A method of making a copy of an original, particularly a positive copy of a diapositive, comprising the steps of photoelectrically scanning the original, line-by-line, to obtain density signals; electronically inverting the density signals; directing a beam of radiation against a negative photosensitive material; and influencing the beam by the inverted density signals.
Claim 3
Dependent Claim 17 words
The method of claim 1, wherein said directing step includes exposing the negative material to radiation line-by-line.
Claim 4
Dependent Claim 17 words
The method of claim 1, wherein said directing step comprises exposing the negative material to radiation point-by-point.
Claim 5
Dependent Claim 15 words
The method of claim 1, wherein said beam is generated by a cathode ray tube.
Claim 6
Dependent Claim 12 words
The method of claim 1, wherein said beam is a laser beam.
Claim 7
Dependent Claim 23 words
The method of claim 1, further comprising the step of storing at least some of said density signals prior to said influencing step.
Claim 8
Dependent Claim 13 words
The method of claim 6, wherein said storing step precedes said inverting step.
Claim 9
Dependent Claim 48 words
The method of claim 1, further comprising the step of modifying the inverted signals prior to said influencing step so as to prevent pronounced widening of the beam in response to inverted signals which are generated as a result of scanning low- and medium-density portions of the original.
Claim 10
Dependent Claim 27 words
The method of claim 8, wherein said influencing step includes selecting the intensity of the beam and the duration of exposure of negative material to the beam.
Claim 11
Dependent Claim 62 words
Apparatus for making a copy of an original, particularly a copy of a diapositive on negative photosensitive material, comprising means for photoelectrically scanning the original, line-by-line, to obtain density signals; means for electronically inverting said density signals; means for directing a beam of radiation upon negative photosensitive material; and means for influencing the beam in accordance with the characteristics of inverted signals.
Claim 12
Dependent Claim 62 words
Apparatus for making a copy of an original, particularly a copy of a diapositive on negative photosensitive material, comprising means for photoelectrically scanning the original, line-by-line, to obtain density signals; means for electronically inverting said density signals; means for directing a beam of radiation upon negative photosensitive material; and means for influencing the beam in accordance with the characteristics of inverted signals.
Claim 13
Dependent Claim 14 words
The apparatus of claim 10, wherein said directing means comprises a cathode ray tube.
Claim 14
Dependent Claim 12 words
The apparatus of claim 10, wherein said directing means comprises a laser.
Claim 15
Dependent Claim 25 words
The apparatus of claim 10, wherein said directing means comprises means for emitting a beam with a profile whose intensity decreases outwardly from the center.
Claim 16
Dependent Claim 21 words
The apparatus of claim 13, wherein said directing means comprises means for emitting a beam having an approximately Gaussian intensity distribution.
Claim 17
Dependent Claim 58 words
The apparatus of claim 10, wherein said directing means includes means for emitting a light beam containing light in the basic colors red, green and blue, and further comprising mobile red, green and blue color filters and means for moving said filters seriatim across the path of the beam between said light emitting means and the negative material.
Claim 18
Independent Claim 100 words
A method of making a copy of an original having a first region of a first density and a second region of a lower second density, said method comprising the steps of scanning said original to obtain a first density signal for said first region and a second density signal for said second region; inverting said density signals; directing a beam of radiation against a photosensitive material; and controlling the width of said beam by the inverted density signals so that the inverted second density signal results results in a smaller beam width than does the inverted first density signal.
Claim 19
Independent Claim 100 words
A method of making a copy of an original having a first region of a first density and a second region of a lower second density, said method comprising the steps of scanning said original to obtain a first density signal for said first region and a second density signal for said second region; inverting said density signals; directing a beam of radiation against a photosensitive material; and controlling the width of said beam by the inverted density signals so that the inverted second density signal results results in a smaller beam width than does the inverted first density signal.
Claim 20
Dependent Claim 102 words
Apparatus for making a copy of an original having a first region of a first density and a second region of a lower second density, said apparatus comprising means for scanning the original to obtain a first density signal for the first region and a second density signal for the second region; means for inverting the density signals; means for directing a beam of radiation upon photosensitive material; and means for controlling the width of the beam by the inverted density signals so that the inverted second density signal results in a smaller beam width than does the inverted first density signal.
Claim 21
Dependent Claim 102 words
Apparatus for making a copy of an original having a first region of a first density and a second region of a lower second density, said apparatus comprising means for scanning the original to obtain a first density signal for the first region and a second density signal for the second region; means for inverting the density signals; means for directing a beam of radiation upon photosensitive material; and means for controlling the width of the beam by the inverted density signals so that the inverted second density signal results in a smaller beam width than does the inverted first density signal.

References Cited (Backward Citations)

DE1268657B Cited
US4368484A Cited
US4349835A Cited
US4393398A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1991-03-01 1991-08-31 1992-03-01 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1995-03-01 1995-08-31 1996-03-01 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1999-03-01 1999-08-31 2000-03-01 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag