US3578845A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Holographic focusing diffraction gratings for spectroscopes and method of making same
Assignee: Northrop Grumman Space and Mission Systems Corp
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Filing: 1968-02-12
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Granted: 1971-05-18
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Expires: 1988-02-12
Abstract
Abstract A method making a focusing diffraction grating including casting a diverging beam of coherent light on a photographic plate, casting a convergent beam of coherent light on the same plate so that the beams interfere with each other on the light-sensitive plane of the plate, and then developing the plate. A holographic focusing diffraction grating having a plurality of curved, spaced grating lines on the face of the grating, the lines having specific curves and spacing relating to specific predetermined wavelengths of light for diffracting specific wavelengths of light at predetermined angles. A spectroscope, spectrograph, or spectrometer having a holographic focusing diffraction grating.
Inventors
- 👤 Robert E Brooks
- 👤 Lee O Heflinger
- 👤 Ralph F Wuerker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 13:34
CPC Classifications
G; G02; G02B; G02B5/00; G02B5/32
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
71 words
A focusing diffraction and dispersing grating, comprising a hologram made in the process of: a. simultaneously casting a divergent beam of coherent light and a convergent beam of coherent light on the same surface and from the same side of a light-sensitive means disposed in a plane so that said beams interfere with each other on the said light-sensitive surface only of said light-sensitive means; and b. developing said light-sensitive means.
Claim 2
Dependent Claim
71 words
A focusing diffraction and dispersing grating, comprising a hologram made in the process of: a. simultaneously casting a divergent beam of coherent light and a convergent beam of coherent light on the same surface and from the same side of a light-sensitive means disposed in a plane so that said beams interfere with each other on the said light-sensitive surface only of said light-sensitive means; and b. developing said light-sensitive means.
Claim 3
Dependent Claim
21 words
A focusing diffraction grating as defined in claim 1 wherein each of said beams of coherent light has a spherical wavefront.
Claim 4
Dependent Claim
32 words
A focusing diffraction grating as defined in claim 1 wherein one of said beams of coherent light has a cylindrical wavefront and the other beam of coherent light has a spherical wavefront.
Claim 5
Dependent Claim
21 words
A focusing diffraction grating as defined in claim 1 wherein each of said beams of coherent light has a cylindrical wavefront.
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) | 1974-05-17 | 1974-11-16 | 1975-05-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-05-17 | 1978-11-16 | 1979-05-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-05-17 | 1982-11-16 | 1983-05-18 | $7700.00 | Window Closed / Lapsed |