US3670305A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Lensless optical recognition system
Assignee: Unisys Corp
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Filing: 1970-09-30
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Granted: 1972-06-13
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Expires: 1990-09-30
Abstract
Abstract A lensless recognition system including a hologram having interference patterns therein corresponding to known characters. The interference patterns are formed by a character beam which passes through a transparent mask of the character to be recorded and intersects a reference beam on a photographic plate. In the recognition process quasi-monochromatic incoherent illumination from an unknown character transmits through the hologram which is obtained by developing and bleaching the photographic plate. Correlated output signals of varying intensity are formed in the output plane at the locations occupied during the recording process by the transparent masks which most closely correspond to the unknown character. Each of a plurality of pinholes positioned at the locations corresponding to each mask transparency transmits the central value of a correlated output signal. A photodetector aligned with each pinhole senses the transmitted central value and produces a current signal that is processed in a postprocessor to provide an output signal that is indicative of the corresponding known character.
Inventors
- 👤 William T Maloney
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 23:37
CPC Classifications
G; G03; G03H; G03H1/00; G06; G06V; G06V10/00; G06V10/88
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
104 words
A lensless optical recognition device comprising holographic means for filtering impinging quasi-monochromatic incoherent illumination from an unknown character by transmission through said holographic means producing an intensity output signal, discriminator means for receiving said intensity output signal and passing a central value signal corresponding to the central value of said intensity output signal, detector means responsive to said central value signal producing an electrical signal in accordance with said central value signal, and signal processing means coupled to said detector means to receive said electrical signal and provide an output signal indicative of a known character that most closely corresponds to said unknown character.
Claim 2
Dependent Claim
104 words
A lensless optical recognition device comprising holographic means for filtering impinging quasi-monochromatic incoherent illumination from an unknown character by transmission through said holographic means producing an intensity output signal, discriminator means for receiving said intensity output signal and passing a central value signal corresponding to the central value of said intensity output signal, detector means responsive to said central value signal producing an electrical signal in accordance with said central value signal, and signal processing means coupled to said detector means to receive said electrical signal and provide an output signal indicative of a known character that most closely corresponds to said unknown character.
Claim 3
Dependent Claim
68 words
A lensless optical recognition device as described in claim 1 in which said holographic means includes means for filtering impinging quasi-monochromatic incoherent illumination from a feature of an unknown character by transmission through said holographic means producing an intensity output signal, and said signal processing means includes logic means for determining the presence of said feature providing an output signal indicative of a known character having said feature.
Claim 4
Dependent Claim
67 words
A lensless optical recognition device as described in claim 1 in which said holographic means includes means for filtering impinging quasi-monochromatic incoherent illumination from subfeatures of an unknown character by transmission through said holographic means producing an intensity output signal, and said signal processing means includes logic means for determining the presence of said subfeatures providing an output signal indicative of a known character having said subfeatures.
Claim 5
Dependent Claim
44 words
A lensless optical recognition device as described in claim 1 in which said holographic means includes a plurality of interference patterns disposed over the useful area of said holographic means corresponding to each mask transparency of a plurality of mask transparencies of known characters.
Claim 6
Dependent Claim
44 words
A lensless optical recognition device as described in claim 1 in which said holographic means includes a plurality of interference patterns spatially positioned within separate areas over the useful area of said holographic means corresponding to a plurality of mask transparencies of known characters.
Claim 7
Dependent Claim
29 words
A lensless optical recognition device as described in claim 1 in which said holographic means includes a hologram having an emulsion of sufficient thickness to contain Bragg phase planes.
Claim 8
Dependent Claim
20 words
An optical recognition device as described in claim 1 in which said discriminator means includes a plurality of coplanar pinholes.
Claim 9
Dependent Claim
22 words
An optical recognition device as described in claim 1 in which said discriminator means includes a plurality of optical fiber transmission lines.
Claim 10
Dependent Claim
25 words
A lensless optical recognition device as described in claim 1 in which said detector means includes a plurality of photodetectors positioned behind said discriminator means.
Claim 11
Dependent Claim
124 words
An optical recognition device comprising holographic means having disposed therein an interference pattern recorded from a mask transparency of a known character for producing a correlated intensity output signal having a central value of intensity in response to impinging quasi-monochromatic incoherent illuminations from an unknown character which corresponds to said known character, discriminator means having an aperture disposed in the same position with respect to said holographic means as said mask transparency during recording and passing said central value of intensity, detector means coupled to said discriminator means for producing an optimum electrical signal in response to said central value of intensity, signal processing means coupled to said detector means providing an output signal indicating that said unknown character corresponds to said known character.
Claim 12
Dependent Claim
124 words
An optical recognition device comprising holographic means having disposed therein an interference pattern recorded from a mask transparency of a known character for producing a correlated intensity output signal having a central value of intensity in response to impinging quasi-monochromatic incoherent illuminations from an unknown character which corresponds to said known character, discriminator means having an aperture disposed in the same position with respect to said holographic means as said mask transparency during recording and passing said central value of intensity, detector means coupled to said discriminator means for producing an optimum electrical signal in response to said central value of intensity, signal processing means coupled to said detector means providing an output signal indicating that said unknown character corresponds to said known character.
Claim 13
Dependent Claim
136 words
An optical recognition device comprising holographic means having disposed therein a plurality of interference patterns recorded from discretely positioned mask transparencies of known characters for producing a correlated intensity output signal having a central value of intensity in response to impinging quasi-monochromatic incoherent illumination from an unknown character, discriminator means having a plurality of apertures disposed with respect to said holographic means at positions corresponding to said discretely positioned mask transparencies during recording fOr passing said central value of intensity, detector means coupled to each of said plurality of apertures for producing an optimum electrical signal in response to said central value of intensity, signal processing means coupled to said detector means to receive said optimum electrical signal and provide an output signal indicative of a known character that most closely corresponds to said unknown character.
Claim 14
Dependent Claim
136 words
An optical recognition device comprising holographic means having disposed therein a plurality of interference patterns recorded from discretely positioned mask transparencies of known characters for producing a correlated intensity output signal having a central value of intensity in response to impinging quasi-monochromatic incoherent illumination from an unknown character, discriminator means having a plurality of apertures disposed with respect to said holographic means at positions corresponding to said discretely positioned mask transparencies during recording fOr passing said central value of intensity, detector means coupled to each of said plurality of apertures for producing an optimum electrical signal in response to said central value of intensity, signal processing means coupled to said detector means to receive said optimum electrical signal and provide an output signal indicative of a known character that most closely corresponds to said unknown character.
Claim 15
Dependent Claim
97 words
An optical recognition device as described in claim 11 in which said holographic means produces sequential correlated intensity output signals having central values of intensity in response to impinging quasi-monochromatic incoherent illumination from sequentially presented unknown characters at specific angles associated with said known characters, said discriminating means sequantially passes said central values of intensity, said detector means produces a series of optimum electrical signals in response to said central values of intensity and said processing means provides a series of output signals indicative of known characters that correspond most closely to said sequentially presented unknown characters.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-06-13 | 1975-12-13 | 1976-06-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-06-13 | 1979-12-13 | 1980-06-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-06-13 | 1983-12-13 | 1984-06-13 | $7700.00 | Window Closed / Lapsed |