US5146287A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Slant angle laser scanner
Assignee: Northrop Grumman Corp
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Filing: 1989-10-20
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Granted: 1992-09-08
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Expires: 2009-10-20
Abstract
Abstract A slant angle laser scanner for detecting underwater hazards, particularly those having a long axis along a radial from the ship such as torpedoes, using a laser, an electro-optical scanner and a rotatably mounted mirror to scan the ocean surface with optical beams at a low angle of incidence to form a circular pattern of radial scans surrounding the ship. The time of return of reflections can be measured to determine the depth of the hazard and the element illuminated within the liner array of photosensitive detectors indicates the location of the hazard along the radial scan. A boresight detector is used to detect the reflections and determine location and depth of the hazard.
Inventors
- 👤 Bruce M. Carder
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 09:00
CPC Classifications
G; G01; G01S; G01S17/00; G01S17/02; G01S17/06; G01S17/42
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
98 words
A slant angle laser scanner for detecting underwater objects from an ocean platform, comprising means forming a collimated laser beam, electro-optical means positioned to receive said laser beam and for scanning the beam along a series of radial paths centered at the platform, each of which proceeds from a location removed from the platform and works toward a location nearer the platform, means for moving the direction of scan progressively in azimuth after each radial scan, and means for gating the imaging signals to discriminate against sea surface echo and to determine the depth of said underwater objects.
Claim 2
Dependent Claim
98 words
A slant angle laser scanner for detecting underwater objects from an ocean platform, comprising means forming a collimated laser beam, electro-optical means positioned to receive said laser beam and for scanning the beam along a series of radial paths centered at the platform, each of which proceeds from a location removed from the platform and works toward a location nearer the platform, means for moving the direction of scan progressively in azimuth after each radial scan, and means for gating the imaging signals to discriminate against sea surface echo and to determine the depth of said underwater objects.
Claim 3
Dependent Claim
60 words
The slant angle laser scanner claimed in claim 1, wherein the scanning means further comprises: a rotatably mounted optical mirror for reflecting the optical beam from the laser means to the ocean surface; means for creating pulses of the optic beam; electro-optic scanning means for varying the angle of reflection of the optical beam; and means for rotating the mirror.
Claim 4
Dependent Claim
22 words
The slant angle laser scanner claimed in claim 1, wherein the detecting means further comprises: a linear array of photosensitive detector elements.
Claim 5
Dependent Claim
22 words
The slant angle laser scanner claimed in claim 1, wherein the detecting means is mounted along the boresight of the laser means.
Claim 6
Independent Claim
86 words
A method for slant angle laser scanning for detecting underwater objects from an ocean platform, comprising forming a collimated laser beam, electro-optically scanning the beam along a series of radial paths centered at the platform, each of which proceeds from a location removed from the platform and works toward a location nearer the platform, moving the direction of scan progressively in azimuth after each radial scan, and gating the imaging signals to discriminate against sea surface echo and to determine the depth of said underwater objects.
Claim 7
Independent Claim
86 words
A method for slant angle laser scanning for detecting underwater objects from an ocean platform, comprising forming a collimated laser beam, electro-optically scanning the beam along a series of radial paths centered at the platform, each of which proceeds from a location removed from the platform and works toward a location nearer the platform, moving the direction of scan progressively in azimuth after each radial scan, and gating the imaging signals to discriminate against sea surface echo and to determine the depth of said underwater objects.
Claim 8
Independent Claim
26 words
The method of detecting underwater hazards claimed in claim , wherein the scanning step further comprises: forming a circular pattern of radial scans surrounding the platform.
Claim 9
Dependent Claim
49 words
The method of detecting underwater hazards claimed in claim 6, wherein the scanning step further comprises: reflecting the optical beam from the laser means to the ocean surface; and varying the angle of reflection of the optical beam to radially scan the optical beam at the speed of light.
Claim 10
Dependent Claim
48 words
The method of detecting underwater hazards claimed in claim 7, wherein the optical beam is generated in pulses and the scanning step further comprises: rotating the scanned beam about an axis normal to the ocean surface between the pulses and then: radially scanning the beam during the pulses.
Claim 11
Independent Claim
40 words
The method of detecting underwater hazards claimed in 5 wherein the reflection detecting step further comprises: focussing the reflection on elements of a linear array of photosensitive detector elements to determine the location of the hazard along the radial scan.
Claim 12
Independent Claim
30 words
The method of detecting underwater hazards claimed in 5 wherein the reflection detecting step further comprises: determining the depth of the hazard from the time of arrival of the reflection.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-09-08 | 1996-03-09 | 1996-09-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-09-08 | 2000-03-09 | 2000-09-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-09-08 | 2004-03-09 | 2004-09-08 | $7700.00 | Window Closed / Lapsed |