US3778128A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Gated holographic coding system for reducing alignment requirements
Assignee: RCA Corp
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Filing: 1972-05-30
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Granted: 1973-12-11
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Expires: 1992-05-30
Abstract
Abstract Holographic techniques are used to encode and decode information. The image of a point source of light is used to trigger an image sensor into detecting the decoded information when the relative encoding coordinates between a code plate and hologram are reestablished in a decoding apparatus.
Inventors
- 👤 W Hannan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 12:00
CPC Classifications
G; G03; G03H; G03H1/00; G03H1/04; G03H1/0402; G03H1/041
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
221 words
A method of encoding and decoding information comprising the steps of: forming an optical encoder of information; generating first, second and third beams of spatially coherent monochromatic light at a given frequency; transmitting said first beam through an information bearing transparency and then through said optical encoder; focusing said second beam to a point source of light in the plane of said information bearing transparency and then transmitting said second beam through said optical encoder; transmitting said third beam to intersect said first and second beams, emerging from said optical encoder at a recorder sensitive to said intersecting light beams; processing said recorder to form a hologram of said intersecting light beams; generating a fourth beam of spatially coherent monochromatic light at the same frequency as said given frequency; transmitting said fourth beam through said hologram and then through said optical encoder while wobbling said encoder to reconstruct the image of said information bearing transparency and said point source of light; generating an electric gating signal from a fixed light detector sensitive to said image of said point source of light when said print image is detected by said detector; and repeatedly detecting said reconstructed image of said information bearing transparency by an image recorder only when said image recorder is activated by said electric gating signal from said light detector.
Claim 2
Independent Claim
221 words
A method of encoding and decoding information comprising the steps of: forming an optical encoder of information; generating first, second and third beams of spatially coherent monochromatic light at a given frequency; transmitting said first beam through an information bearing transparency and then through said optical encoder; focusing said second beam to a point source of light in the plane of said information bearing transparency and then transmitting said second beam through said optical encoder; transmitting said third beam to intersect said first and second beams, emerging from said optical encoder at a recorder sensitive to said intersecting light beams; processing said recorder to form a hologram of said intersecting light beams; generating a fourth beam of spatially coherent monochromatic light at the same frequency as said given frequency; transmitting said fourth beam through said hologram and then through said optical encoder while wobbling said encoder to reconstruct the image of said information bearing transparency and said point source of light; generating an electric gating signal from a fixed light detector sensitive to said image of said point source of light when said print image is detected by said detector; and repeatedly detecting said reconstructed image of said information bearing transparency by an image recorder only when said image recorder is activated by said electric gating signal from said light detector.
Claim 3
Independent Claim
274 words
A method of encoding and decoding information comprising the steps of: forming first and second complementary optical encoders of information; generating first, second and third beams of spatially coherent monochromatic light at a given frequency; transmitting said first beam through a beam diffuser, then through an information bearing transparency and then through said first optical encoder; focusing said second beam to a point source of light in the plane of said information bearing transparency; transmitting said third beam to intersect said first and second beams, emerging from said first optical encoder, at a recorder sensitive to said intersecting light beams to form a first exposure; transmitting said first beam for a second time through said beam diffuser and then through said second optical encoder; transmitting said third beam for a second time to intersect said first beam, emerging from said second optical encoder, at said recorder to form a second exposure; processing said recorder to form a hologram of said intersecting light beams; generating a fourth beam of spatially coherent monochromatic light at the same frequency as said given frequency; transmitting said fourth beam through said hologram and then through said first optical encoder while wobbling said encoder to reconstruct the image of said information bearing transparency and said point source of light; generating an electric gating signal from a fixed light detector sensitive to said image of said point source of light when said print image is detected by said detector light; and repeatedly detecting said reconstructed image of said image bearing transparency by an image recorder only when said image recorder is activated by said electric gating signal from said light detector.
Claim 4
Independent Claim
274 words
A method of encoding and decoding information comprising the steps of: forming first and second complementary optical encoders of information; generating first, second and third beams of spatially coherent monochromatic light at a given frequency; transmitting said first beam through a beam diffuser, then through an information bearing transparency and then through said first optical encoder; focusing said second beam to a point source of light in the plane of said information bearing transparency; transmitting said third beam to intersect said first and second beams, emerging from said first optical encoder, at a recorder sensitive to said intersecting light beams to form a first exposure; transmitting said first beam for a second time through said beam diffuser and then through said second optical encoder; transmitting said third beam for a second time to intersect said first beam, emerging from said second optical encoder, at said recorder to form a second exposure; processing said recorder to form a hologram of said intersecting light beams; generating a fourth beam of spatially coherent monochromatic light at the same frequency as said given frequency; transmitting said fourth beam through said hologram and then through said first optical encoder while wobbling said encoder to reconstruct the image of said information bearing transparency and said point source of light; generating an electric gating signal from a fixed light detector sensitive to said image of said point source of light when said print image is detected by said detector light; and repeatedly detecting said reconstructed image of said image bearing transparency by an image recorder only when said image recorder is activated by said electric gating signal from said light detector.
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) | 1976-12-10 | 1977-06-11 | 1977-12-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-12-10 | 1981-06-11 | 1981-12-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-12-10 | 1985-06-11 | 1985-12-11 | $7700.00 | Window Closed / Lapsed |