Optical differential tilt sensor
Patent 4981354 Issued on January 1, 1991. Estimated Expiration Date: 
March 13, 2009. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
March 13, 2009. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent References 3623814 Wide field of view remote laser position sensor Optically phased laser transmitter Synthetic aperture multi-telescope tracker apparatus Patent #: 4667090 InventorsAssigneeApplicationNo. 322380 filed on 03/13/1989US Classes:356/139.1, Photodetection of inclination from level or vertical250/203.1, Following a target (e.g., a star or instrument pointer or other object) other than a pattern356/141.1, With photodetection of reflected beam angle with respect to a unidirectional source beam356/144, With plural images356/147, Measurement in two planes (e.g., azimuth and elevation; hour angle and declination)356/365, With birefringent element359/238Light wave temporal modulation (e.g., frequency, amplitude, etc.)ExaminersPrimary: Tarcza, Thomas H.Assistant: Wallace, Linda J. Attorney, Agent or FirmInternational ClassesC01C 001/00G01J 004/00 AbstractAn electrooptical sensor system directly measures the angle between two nearly parallel collimated laser beams. After focussing with a positive lens, the beams pass through a photoelastic modulator, a quarter wave retardation plate, and two polarizers. The beams then hit a lateral cell position sensor. Electrical signals from the lateral cell are processed with special electronics to yield a voltage which is proportional to the angular difference between the two beams. The sensor measures extremely small angles and operates at a high bandwidth. Its primary application is in the control of phased array optical telescopes.Other References
| |
