Patent US3746454A successfully refreshed from Google Patents.
US3746454A
Expired / Lapsed
US
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Infrared receiver for optical radar
Assignee: United States Department of the Navy
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Filing: 1971-03-03
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Granted: 1973-07-17
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Expires: 1991-03-03
Abstract
Abstract There is disclosed a receiver for an optical radar utilizing a two-dimensional array of microlens image dissectors which completely fills an area of an image plane. Each microlens is directly coupled to a mixer-detector element. The array is adapted to be illuminated with returned focus radiation from a remote reflecting target and with a planar wave of optical energy from a local oscillator. The output signals of the mixerdetectors are analyzed and utilized to orientate the array such that the maximum amplitude output signal corresponds to the central microlens of the array.
Inventors
- 👤 F Arams
- 👤 F Pace
- 👤 R Lange
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:53
CPC Classifications
G; G01; G01S; G01S17/00; G01S17/02; G01S17/06; G01J; G01J1/00; G01J1/02; G01J1/04; G01J1/0407; G01J1/0411; G01J1/0422; G01J1/42; G01J1/4228; G02; G02F; G02F2/00; G02F2/002; G01J1/0204; G01J1/0209
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
167 words
Apparatus for use in an optical radar system of the type employing a pulsed laser as the transmitting means, the combination of a multiplicity of microlenses arranged in a two-dimensional array such that the front radiant energy receiving surfaces of said microlenses completely fill an area of an image plane; a mixer-detector element contacting the back surface of each microlens; means for illuminating the front surfaces of said array of microlenses with a planar wave of optical radiation whose frequency differs from that of said pulsed laser, said planar wave of optical radiation acting within said mixer-detectors as a heterodyning signal with any laser radiation returned from any remote reflecting target within the field of view of said array and focused thereon; and means responsive to the amplitude of the signals appearing in the outputs of said mixer-detector elements for positioning said array of microlenses such that the longitudinal axis of symmetry of a central microlens of said array is spatially aligned with said remote reflecting target.
Claim 2
Dependent Claim
167 words
Apparatus for use in an optical radar system of the type employing a pulsed laser as the transmitting means, the combination of a multiplicity of microlenses arranged in a two-dimensional array such that the front radiant energy receiving surfaces of said microlenses completely fill an area of an image plane; a mixer-detector element contacting the back surface of each microlens; means for illuminating the front surfaces of said array of microlenses with a planar wave of optical radiation whose frequency differs from that of said pulsed laser, said planar wave of optical radiation acting within said mixer-detectors as a heterodyning signal with any laser radiation returned from any remote reflecting target within the field of view of said array and focused thereon; and means responsive to the amplitude of the signals appearing in the outputs of said mixer-detector elements for positioning said array of microlenses such that the longitudinal axis of symmetry of a central microlens of said array is spatially aligned with said remote reflecting target.
Claim 3
Dependent Claim
28 words
In an arrangement as defined in claim 1 wherein the contacting area of each mixer-detector element is of the same size as the back surface of each microlens.
Claim 4
Dependent Claim
39 words
In an arrangement as defined in claim 1 wherein said microlenses are made of germanium and said detector-mixer elements are made of a germanium-copper mixture whenever the pulsed laser is operating in the 10.6 micron region of the spectrum.
Claim 5
Dependent Claim
34 words
In an arrangement as defined in claim 1 wherein the back surface of each microlens is planar and each mixer-detector element is of generally rectangular shape with its length considerably greater than its width.
Claim 6
Dependent Claim
73 words
In an arrangement as defined in claim 1 wherein said multiplicity of microlenses are arranged in horizontal rows and vertical columns and wherein a microstrip transmission line is connected to the output of each mixer-detector element, the microstrip transmission lines connected to those mixer-detector elements which contact a particular row of microlenses having a fanout pattern so as to minimize those portions of these microstrip transmission lines which are parallel to each other.
Claim 7
Dependent Claim
33 words
In an arrangement as defined in claim 5 wherein the microlenses, the mixer-detector elements and the microstrip transmission lines are conductibly cooled to a cryogenic temperature for minimizing thermionic noise and random interference.
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) | 1976-07-16 | 1977-01-15 | 1977-07-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-16 | 1981-01-15 | 1981-07-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-16 | 1985-01-15 | 1985-07-17 | $7700.00 | Window Closed / Lapsed |