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US4469407A Expired / Lapsed US ⏱️ 0.0 years remaining

Laser apodizing filter

Assignee: Polaroid Corp
•
Filing: 1982-02-08
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Granted: 1984-09-04
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Expires: 2002-02-08
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Abstract

Abstract A laser beam apodizing filter comprising a print-out silver image comprised of silver grains having a diameter of about 0.5 μm or less, said image being proportional in density distribution to the intensity distribution of the laser beam cross-section. Also disclosed is a method for forming the filter and a laser diffraction imaging apparatus, for making diffraction gratings, which employs the filter.

Inventors

  • 👤 James J. Cowan
  • 👤 Andrew B. Holland

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-27 08:08
CPC Classifications
G; G02; G02B; G02B27/00; G02B27/58; G02B27/09; G02B27/0927; G02B27/0938; G02B27/0988; H; H01; H01S; H01S3/00; H01S3/005

Claims Analysis

Total Claims: 19
Claim 1
Independent Claim 46 words
A laser beam apodizing filter comprising a laser beam transparent support carrying a print out silver image in terms of silver grains having a diameter of about 0.5 μm or less, said image being proportional in density distribution to the intensity distribution of said laser beam.
Claim 2
Dependent Claim 46 words
A laser beam apodizing filter comprising a laser beam transparent support carrying a print out silver image in terms of silver grains having a diameter of about 0.5 μm or less, said image being proportional in density distribution to the intensity distribution of said laser beam.
Claim 3
Dependent Claim 12 words
The product of claim 1 wherein said support is optical quality glass.
Claim 4
Dependent Claim 13 words
The product of claim 1 wherein said support is a non-birefringent plastic support.
Claim 5
Dependent Claim 15 words
The product of claim 1 wherein said image is laminated between optical quality glass plates.
Claim 6
Independent Claim 91 words
A method for forming a laser beam apodizing filter which comprises exposing to the laser beam a print out silver halide emulsion carried on a support transparent to said laser beam, the silver halide grains of said silver halide emulsion being substantially uniform in diameter and having an average diameter of about 0.5 μm or less and a silver to gel ratio of greater than 1 and fixing the silver image formed in the thus-exposed emulsion, said silver image being substantially free of silver grains larger than said silver halide grains.
Claim 7
Independent Claim 91 words
A method for forming a laser beam apodizing filter which comprises exposing to the laser beam a print out silver halide emulsion carried on a support transparent to said laser beam, the silver halide grains of said silver halide emulsion being substantially uniform in diameter and having an average diameter of about 0.5 μm or less and a silver to gel ratio of greater than 1 and fixing the silver image formed in the thus-exposed emulsion, said silver image being substantially free of silver grains larger than said silver halide grains.
Claim 8
Dependent Claim 17 words
The method of claim 5 wherein said emulsion has an average grain size of about 0.4 μm.
Claim 9
Dependent Claim 14 words
The method of claim 5 wherein said emulsion is about 1-5 μm in thickness.
Claim 10
Dependent Claim 14 words
The method of claim 7 wherein said emulsion is about 2 μm in thickness.
Claim 11
Dependent Claim 12 words
The method of claim 5 wherein said support is optical quality glass.
Claim 12
Dependent Claim 12 words
The method of claim 6 wherein said support is a plastic support.
Claim 13
Dependent Claim 155 words
A laser diffraction imaging apparatus comprising: a laser; a beam splitter; a first mirror; and a second mirror; said beam splitter being disposed so as to split the light emanating from said laser such that a first portion is incident on said first mirror and a second portion is incident on said second mirror, a target; a first expansion lens and spatial filter disposed between said first mirror and said target in the path of laser light therebetween; a second expansion lens and spatial filter disposed in the laser beam path and between said second mirror and said target; wherein there is also disposed in said laser beam path an apodizing filter comprising a support transparent to said laser beam, said support carrying a print out silver image of silver grains having a diameter of about 0.5 μm or less, said image being proportional in density distribution to the intensity distribution of said laser beam.
Claim 14
Dependent Claim 155 words
A laser diffraction imaging apparatus comprising: a laser; a beam splitter; a first mirror; and a second mirror; said beam splitter being disposed so as to split the light emanating from said laser such that a first portion is incident on said first mirror and a second portion is incident on said second mirror, a target; a first expansion lens and spatial filter disposed between said first mirror and said target in the path of laser light therebetween; a second expansion lens and spatial filter disposed in the laser beam path and between said second mirror and said target; wherein there is also disposed in said laser beam path an apodizing filter comprising a support transparent to said laser beam, said support carrying a print out silver image of silver grains having a diameter of about 0.5 μm or less, said image being proportional in density distribution to the intensity distribution of said laser beam.
Claim 15
Dependent Claim 10 words
The apparatus of claim 11 wherein said support is glass.
Claim 16
Dependent Claim 12 words
The apparatus of claim 11 wherein said support is a plastic support.
Claim 17
Dependent Claim 15 words
The apparatus of claim 13 wherein said image is laminated between optical quality glass plates.
Claim 18
Dependent Claim 17 words
The apparatus of claim 13 wherein both of said first and second paths contain an apodizing filter.
Claim 19
Dependent Claim 17 words
The apparatus of claim 13 wherein said apodizing filter is intermediate said laser and said beam splitter.

References Cited (Backward Citations)

GB1206035A Cited
US3700314A Cited
US4094575A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1987-09-04 1988-03-05 1988-09-04 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1991-09-04 1992-03-05 1992-09-04 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1995-09-04 1996-03-05 1996-09-04 $7700.00 Window Closed / Lapsed

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