Patent US3949160A successfully refreshed from Google Patents.
US3949160A
Expired / Lapsed
US
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Electro-optic readout of thermoplastic deformation patterns
Assignee: Xerox Corp
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Filing: 1975-01-06
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Granted: 1976-04-06
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Expires: 1995-01-06
Abstract
Abstract A method of and apparatus for reading out information disposed as a surface deformation such as a thermoplastic deformation pattern is disclosed in accordance with the teachings of the present invention. A coherent light beam is projected to the surface deformation pattern and one of the first order components of the diffraction pattern received from the deformation pattern is imaged onto a surface. At the surface, the first order component is mixed with a further coherent light beam to form an interference pattern comprised of image modulated sinusoidal interference fringes. The interference pattern has an intensity that varies as a linear function of the amplitude of the deformation pattern. In a preferred embodiment thereof, the first order component of the diffraction pattern is imaged to the surface by an imaging lens optically positioned out of optical communication with the zero order component of the diffraction pattern. The further coherent light beam is provided by optical filter disposed to receive the zero order component of the diffraction pattern and to transmit the zero order component to the surface. The optical filter includes a lens having a focal point disposed in the focal plane of the imaging lens and offset from the focal point of the imaging lens. The surface at which the interference pattern is formed comprises a photoelectric transducer for generating an electric signal representing the interference pattern, the signal being comprised of an informational component related to the deformation pattern modulated onto a carrier component related to the spatial frequency of the interference fringes. The informational component is recovered by demodulation of the electric signal.
Inventors
- 👤 John C. Heurtley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 19:02
CPC Classifications
H; H04; H04N; H04N5/00; H04N5/76; H04N5/80; H04N5/82; G; G03; G03G; G03G16/00
Claims Analysis
Total Claims: 31
Claim 1
Independent Claim
120 words
A method of projecting an image disposed as a regular periodic surface deformation pattern comprising the steps of: projecting a first coherent light beam to said deformation pattern; imaging a first order component of the diffraction pattern received from said deformation pattern onto an image receiving surface to thereby form a light image on said image receiving surface having an intensity that varies as a function of the square of the amplitude of the periodic deformation pattern; and superposing on said image receiving surface a second coherent light beam to form an interference pattern having an intensity that varies as a linear function of the amplitude of the periodic deformation pattern and that appears as image modulated sinusoidal interference fringes.
Claim 2
Independent Claim
120 words
A method of projecting an image disposed as a regular periodic surface deformation pattern comprising the steps of: projecting a first coherent light beam to said deformation pattern; imaging a first order component of the diffraction pattern received from said deformation pattern onto an image receiving surface to thereby form a light image on said image receiving surface having an intensity that varies as a function of the square of the amplitude of the periodic deformation pattern; and superposing on said image receiving surface a second coherent light beam to form an interference pattern having an intensity that varies as a linear function of the amplitude of the periodic deformation pattern and that appears as image modulated sinusoidal interference fringes.
Claim 3
Dependent Claim
61 words
The method of claim 1 wherein said step of imaging a first order component of the diffraction pattern comprises the steps of receiving said first order component reflected from said deformation pattern; focusing said first order component onto a focal plane; and transmitting said first order component from said focal plane to said image receiving surface along a first optical path.
Claim 4
Dependent Claim
72 words
The method of claim 2 wherein said step of superposing a second coherent light beam comprises the steps of focusing the zero order component of the diffraction pattern reflected from said deformation pattern onto said focal plane at a point offset from the point at which said first order component is focused and transmitting said zero order component from said offset point to said image receiving surface along a second optical path.
Claim 5
Dependent Claim
34 words
The method of claim 3 further comprising the step of optically filtering the diffraction pattern received from said deformation pattern to prevent the transmission of said zero order component along said first optical path.
Claim 6
Dependent Claim
133 words
Apparatus for increasing the intensity of a projected image of a periodic surface deformation pattern, comprising: means for projecting a beam of coherent light to said deformation pattern; imaging lens means for imaging a first order component of the diffraction pattern received from said deformation pattern onto an image receiving surface, said imaging lens means being optically positioned out of optical communication with the zero order component of said diffraction pattern; and optical filter means disposed to receive said zero order component and to transmit said zero order component to said image receiving surface whereat said zero order component mixes with said first order component to form an interference pattern comprised of image modulated sinusoidal interference fringes having an intensity that varies as a linear function of the amplitude of the deformation pattern.
Claim 7
Dependent Claim
133 words
Apparatus for increasing the intensity of a projected image of a periodic surface deformation pattern, comprising: means for projecting a beam of coherent light to said deformation pattern; imaging lens means for imaging a first order component of the diffraction pattern received from said deformation pattern onto an image receiving surface, said imaging lens means being optically positioned out of optical communication with the zero order component of said diffraction pattern; and optical filter means disposed to receive said zero order component and to transmit said zero order component to said image receiving surface whereat said zero order component mixes with said first order component to form an interference pattern comprised of image modulated sinusoidal interference fringes having an intensity that varies as a linear function of the amplitude of the deformation pattern.
Claim 8
Dependent Claim
38 words
The apparatus of claim 5 wherein said optical filter means includes lens means having a focal point disposed in the focal plane of said imaging lens means and offset from the focal point of said imaging lens means.
Claim 9
Dependent Claim
36 words
The apparatus of claim 6 wherein said means for projecting a beam of coherent light comprises a laser light source and laser beam expanding means optically interposed between said laser light source and said deformation pattern.
Claim 10
Independent Claim
246 words
A method of transmitting an image disposed as a regular periodic surface deformation pattern comprising the steps of: scanning successive portions of said deformation pattern with a coherent light beam; imaging at least a first order component of the diffraction pattern received from each scanned portion of said deformation pattern onto a photoconductive surface of a vidicon image transducer by focusing said at least first order component onto a focal plane and projecting said at least first order component from said focal plane to said photoconductive surface; focusing the zero order component of said diffraction pattern received from each scanned portion of said deformation pattern onto said focal plane at a point offset from the point at which said at least first order component is focused and projecting said zero order component from said offset point to said photoconductive surface whereat said at least first order component and said zero order component are mixed to form an interference pattern; flooding said photoconductive surface with relatively high intensity light intermittent each scan interval to erase residual signals of an immediately preceding scanned portion of said deformation pattern; demodulating the electrical representations generated by said vidicon image transducer in response to said mixed first order components and said zero order component, said electrical representations comprising an informational component related to each scanned portion of said deformation pattern modulated onto a carrier component related to the interference frequency, to thereby recover said informational component; and transmitting said informational component.
Claim 11
Independent Claim
246 words
A method of transmitting an image disposed as a regular periodic surface deformation pattern comprising the steps of: scanning successive portions of said deformation pattern with a coherent light beam; imaging at least a first order component of the diffraction pattern received from each scanned portion of said deformation pattern onto a photoconductive surface of a vidicon image transducer by focusing said at least first order component onto a focal plane and projecting said at least first order component from said focal plane to said photoconductive surface; focusing the zero order component of said diffraction pattern received from each scanned portion of said deformation pattern onto said focal plane at a point offset from the point at which said at least first order component is focused and projecting said zero order component from said offset point to said photoconductive surface whereat said at least first order component and said zero order component are mixed to form an interference pattern; flooding said photoconductive surface with relatively high intensity light intermittent each scan interval to erase residual signals of an immediately preceding scanned portion of said deformation pattern; demodulating the electrical representations generated by said vidicon image transducer in response to said mixed first order components and said zero order component, said electrical representations comprising an informational component related to each scanned portion of said deformation pattern modulated onto a carrier component related to the interference frequency, to thereby recover said informational component; and transmitting said informational component.
Claim 12
Dependent Claim
53 words
The method of claim 8 wherein said step of imaging at least a first order component comprises the steps of: optically separating the zero order component of the diffraction pattern from the remaining order components thereof; and transmitting said at least first order component to said focal plane by a first optical path.
Claim 13
Dependent Claim
31 words
The method of claim 9 wherein said step of focusing said zero order component comprises transmitting said optically separated zero order component to said offset point by a second optical path.
Claim 14
Independent Claim
121 words
A method of electrically transmitting information contained in a regular periodic surface deformation pattern comprising the steps of: irradiating said regular periodic surface deformation pattern with a coherent light beam; imaging a first order component of the diffraction pattern received from the irradiated surface deformation pattern onto the surface of a photoelectric transducer; mixing said first order component with a further coherent light beam at said transducer surface to form an interference pattern thereat and to thereby generate an electrical representation thereof comprised of an electrical informational component related to said surface deformation pattern modulated onto an electrical carrier component related to the interference frequency; demodulating said electrical representation to recover said electrical informational component; and transmitting said electrical information component.
Claim 15
Independent Claim
121 words
A method of electrically transmitting information contained in a regular periodic surface deformation pattern comprising the steps of: irradiating said regular periodic surface deformation pattern with a coherent light beam; imaging a first order component of the diffraction pattern received from the irradiated surface deformation pattern onto the surface of a photoelectric transducer; mixing said first order component with a further coherent light beam at said transducer surface to form an interference pattern thereat and to thereby generate an electrical representation thereof comprised of an electrical informational component related to said surface deformation pattern modulated onto an electrical carrier component related to the interference frequency; demodulating said electrical representation to recover said electrical informational component; and transmitting said electrical information component.
Claim 16
Dependent Claim
59 words
The method of claim 11 wherein said step of demodulating said electrical representation comprises the steps of: multiplying said electrical representation with a reference signal having a frequency equal to the frequency of said electrical carrier component; and filtering the resultant product signal to remove frequency components therein that exceed the maximum frequency included in said electrical informational component.
Claim 17
Dependent Claim
47 words
The method of claim 11 wherein said step of demodulating said electrical representation comprises the steps of: full wave linearly rectifying said electrical representation; and filtering the resultant linearly rectified signal to remove frequency components therein that exceed the maximum frequency included in said electrical informational component.
Claim 18
Dependent Claim
64 words
The method of claim 11 wherein said step of imaging said first order component comprises the steps of: optically separating the zero order component of the diffraction pattern from the remaining order components thereof; focusing said at least a first order component onto a focal plane; and projecting said at least said first order component from said focal plane to said photoelectric transducer surface.
Claim 19
Dependent Claim
77 words
The method of claim 14 wherein said step of mixing said at least first order component with a further coherent light beam comprises the steps of: recovering said separated zero order component; focusing said zero order component onto said focal plane at a point offset from the point at which said at least first order component is focused; and projecting said zero order component from said offset point on said focal plane to said photoelectric transducer surface.
Claim 20
Dependent Claim
185 words
Apparatus for transmitting an image disposed as a regular periodic surface deformation pattern to a remote location, comprising: means for projecting a beam of coherent light to said deformation pattern; imaging means in optical communication with no less than a first order component of the diffraction pattern received from said deformation pattern for imaging said first order component onto the surface of a photoelectric transducer; a source of coherent light for transmitting a further beam of coherent light to said photoelectric transducer surface whereat said further beam of coherent light mixes with said first order component to form an interference pattern comprised of image modulated sinusoidal interference fringes; a photoelectric transducer having a surface upon which said interference pattern is formed for generating an electric signal representing said interference pattern, said signal comprised of an informational component related to said deformation pattern modulated onto a carrier component related to the spatial frequency of said interference fringes; demodulation means coupled to said photoelectric transducer for demodulating said electric signal to recover said informational component; and means for transmitting said recovered informational component to said remote location.
Claim 21
Dependent Claim
185 words
Apparatus for transmitting an image disposed as a regular periodic surface deformation pattern to a remote location, comprising: means for projecting a beam of coherent light to said deformation pattern; imaging means in optical communication with no less than a first order component of the diffraction pattern received from said deformation pattern for imaging said first order component onto the surface of a photoelectric transducer; a source of coherent light for transmitting a further beam of coherent light to said photoelectric transducer surface whereat said further beam of coherent light mixes with said first order component to form an interference pattern comprised of image modulated sinusoidal interference fringes; a photoelectric transducer having a surface upon which said interference pattern is formed for generating an electric signal representing said interference pattern, said signal comprised of an informational component related to said deformation pattern modulated onto a carrier component related to the spatial frequency of said interference fringes; demodulation means coupled to said photoelectric transducer for demodulating said electric signal to recover said informational component; and means for transmitting said recovered informational component to said remote location.
Claim 22
Dependent Claim
13 words
The apparatus of claim 16 wherein said photoelectric transducer comprises a vidicon tube.
Claim 23
Dependent Claim
75 words
The apparatus of claim 16 wherein said demodulation means comprises a synchronous detector including: multiplying means coupled to said photoelectric transducer for multiplying said electric signal with a reference carrier signal having a frequency equal to the frequency of said carrier component; and low pass filter means coupled to said multiplying means for attenuating signals having frequencies above a predetermined frequency, said predetermined frequency being greater than the maximum frequency included in said informational component.
Claim 24
Dependent Claim
15 words
The apparatus of claim 16 wherein said demodulation means comprises full wave linear rectifying means.
Claim 25
Dependent Claim
36 words
The apparatus of claim 16 wherein said means for projecting a beam of coherent light comprises a laser light source and laser beam expanding means optically interposed between said laser light source and said deformation pattern.
Claim 26
Dependent Claim
16 words
The apparatus of claim 20 wherein said laser light source comprises an ion pulsed laser system.
Claim 27
Dependent Claim
15 words
The apparatus of claim 20 wherein said laser light source comprises a neodymimum-doped laser system.
Claim 28
Dependent Claim
36 words
The apparatus of claim 16 wherein said imaging means comprises lens means interposed between said deformation pattern and said photoelectric transducer surface and having a focal plane intermediate said lens means and said photoelectric transducer surface.
Claim 29
Dependent Claim
41 words
The apparatus of claim 23 wherein said source of coherent light comprises an effective light source disposed in said focal plane at a point offset from the focal point of said lens means at which said first order component is focused.
Claim 30
Dependent Claim
52 words
The apparatus of claim 24 wherein said effective light source comprises optical filter means disposed to receive the zero order component of the diffraction pattern from said deformation pattern for focusing said zero order component on said offset point from which said zero order component is transmitted to said photoelectric transducer surface.
Claim 31
Dependent Claim
21 words
The apparatus of claim 25 wherein said lens means is optically positioned out of optical communication with said zero order component.
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) | 1979-04-06 | 1979-10-06 | 1980-04-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-04-06 | 1983-10-06 | 1984-04-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-04-06 | 1987-10-06 | 1988-04-06 | $7700.00 | Window Closed / Lapsed |