The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 10, 1983
Filed:
May. 12, 1981
Barr & Stroud Limited, Glasgow, GB;
Abstract
A thermal imager comprises a scanner (13), detector (14) with mount (14A) cooled substantially below ambient temperature, and which via a reflector (16) on the locus (15) along which an image of the detector (14) is effectively scanned provides a characteristic radiation feature to the detector (14) in superimposition with the scanned radiation from the scanner (13). The scanner (13) operates with less than 50% efficiency so that in the detector output signal the scene-derived waveform has a duration T.sub.1 <50%T, where T is the period of the detector output signal. The characteristic radiation feature gives rise to a sync signal at the detector output and is located prior to and closely adjacent the scene-derived waveform at a time interval T.sub.2 prior to the end thereof. This sync signal is detected by a recognition circuit (20) and activates a monostable forming part of a clock circuit (22) for a duration T.sub.3 such that T.sub.2 <T.sub.3 <50%T. The clock circuit (22) controls the timing of signal processing circuitry (24) and a video output device (25) connected to the output of the detector (14).