Patent US3815969A successfully refreshed from Google Patents.
US3815969A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Holography utilizing surface plasmon resonances
Assignee: National Aeronautics and Space Administration
•
Filing: 1973-05-31
•
Granted: 1974-06-11
•
Expires: 1993-05-31
Abstract
Abstract A holographic recording medium employing a substrate having a diffraction grating composed of a plurality of spaced line ridges on a surface thereof together with a first layer consisting of a metal having a plasma wavelength shorter than that of a selected light source and a second layer, or coating, on top of the first layer, consisting of a thin film of photo-sensitive emulsion.
Inventors
- 👤 J Fletcher
- 👤 J Cowan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 03:43
CPC Classifications
G; G03; G03H; G03H1/00; G03H1/04; G03H1/02; G03H1/0252; G03H1/0256; G03H1/0402; G03H2001/0413; G03H2260/00; G03H2260/16
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
15 words
A holographic device as set forth in claim 1 wherein said metal comprises said substrate.
Claim 2
Dependent Claim
120 words
A holographic device for recording holographic images as set forth in claim 1 further comprising: means for generating a beam of coherent light; positioning means for positioning an object to be photographed in a selected position with respect to said surface of said substrate; means for splitting said beam of coherent light and directing one portion of said beam onto a said object and then onto said surface of said substrate and directing a second portion of said beam, being a reference portion, onto said surface at a selected angle of incidence; whereby a further and second reference beam is generated in said coating which propagates across the surface of said diffraction grating creating a plasmon resonance in said coating.
Claim 3
Dependent Claim
50 words
A holographic device as set forth in claim 3 wherein said device includes means for polarizing said reference portion of said beam in a plane, which plane is oriented with respect to said surface at an angle corresponding to the plane in which said selected angle of incidence is measured.
Claim 4
Dependent Claim
33 words
A holographic device as set forth in claim 4 wherein said metal has a shorter plasma wave length characteristic than coherent light generated by said means for generating a beam of coherent light.
References Cited (Backward Citations)
US3623798A
Cited
US3743507A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-06-10 | 1977-12-10 | 1978-06-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-10 | 1981-12-10 | 1982-06-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-10 | 1985-12-10 | 1986-06-11 | $7700.00 | Window Closed / Lapsed |