Patent US3574466A successfully refreshed from Google Patents.
US3574466A
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Angular measurement apparatus
Assignee: GTE Sylvania Inc
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Filing: 1968-04-15
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Granted: 1971-04-13
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Expires: 1988-04-15
Abstract
Abstract Apparatus comprising stationary and rotating electromagnetic energy reflectors oriented to define a common plane wherein the reflectors cooperate with a remote energy source and sensors to provide an angular measure in the common plane between a reference line and a line of sight.
Inventors
- 👤 Charles J Peters
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 22:11
CPC Classifications
B; B64; B64G; B64G1/00; B64G1/22; B64G1/24; B64G1/36; G; G01; G01C; G01C25/00
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
146 words
Apparatus for angular measurement comprising: first and second electromagnetic energy reflectors each having a face disposed orthogonal to a common plane; means supporting said first reflector for rotation about an axis orthogonal to said common plane; means for transmitting a beam of electromagnetic energy to said first reflector, said first reflector being operative to retroreflect an electromagnetic energy pulse when said first reflector is rotated through a first predetermined position, and said first and second reflectors being cooperatively positioned to retroreflect an electromagnetic energy pulse when said first reflector is rotated through a second predetermined position; and means for receiving said retroreflected pulses, said means for receiving including means for measuring the time interval between the retroreflected pulse generated when said rotatable Reflector is passing through said first predetermined position and the retroreflected pulse generated when said rotatable reflector is passing through said second predetermined position.
Claim 2
Dependent Claim
146 words
Apparatus for angular measurement comprising: first and second electromagnetic energy reflectors each having a face disposed orthogonal to a common plane; means supporting said first reflector for rotation about an axis orthogonal to said common plane; means for transmitting a beam of electromagnetic energy to said first reflector, said first reflector being operative to retroreflect an electromagnetic energy pulse when said first reflector is rotated through a first predetermined position, and said first and second reflectors being cooperatively positioned to retroreflect an electromagnetic energy pulse when said first reflector is rotated through a second predetermined position; and means for receiving said retroreflected pulses, said means for receiving including means for measuring the time interval between the retroreflected pulse generated when said rotatable Reflector is passing through said first predetermined position and the retroreflected pulse generated when said rotatable reflector is passing through said second predetermined position.
Claim 3
Dependent Claim
36 words
Apparatus for angular measurement according to claim 1 wherein said means for receiving further includes means for measuring the time interval between successive retroreflected pulses generated when said rotatable reflector passes through said first predetermined position.
Claim 4
Dependent Claim
35 words
Apparatus for angular measurement according to claim 1 wherein said first and second electromagnetic energy reflectors are optical reflecting elements and wherein said means for transmitting a beam of electromagnetic energy includes a light source.
Claim 5
Dependent Claim
80 words
Apparatus for angular measurement according to claim 3 wherein: said first and second optical reflecting elements are roof prisms, each having a ridge line disposed in a common plane and wherein said first predetermined position is the position in which said transmitted beam is orthogonal to the ridge line of said first reflector and said second predetermined position is the position in which the ridge line of said first reflector is orthogonal to the ridge line of said second reflector.
Claim 6
Dependent Claim
24 words
Apparatus for angular measurement according to claim 3 wherein said first reflector is a roof prism and said second reflector is a plane mirror.
References Cited (Backward Citations)
US3218913A
Cited
US3399590A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-04-12 | 1974-10-12 | 1975-04-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-04-12 | 1978-10-12 | 1979-04-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-04-12 | 1982-10-12 | 1983-04-13 | $7700.00 | Window Closed / Lapsed |