| 摘要 |
The positional accuracy obtained when observing an airspace over a wide angular range using a plurality of optical channels arranged at an angle relative to each other to determine the coordinates of a thermal object may be low because the individual channels are relatively large and hence limited in number. An arrangement is provided which comprises a number of optical channels, which scan adjacent solid angles and, via a moving modulation grating 3 which operates as a spatial filter, image each optical channel on a matrix 8 of IR detectors by means of an optical system 5, 6, 7. When an IR detector supplies a signal corresponding to a thermal object to be detected, the coordinate values of the thermal object relative to the relevant optical channel can be derived from the position of said IR detector within the matrix. When the individual IR detector signals are scanned by means of a multiplexer 13 controlled by a counter 14 the counter output 16 may directly represent the binary coded coordinate values. <IMAGE> |
