Abstract:
An image beam from a constant intensity light source is passed through a small area of an image on a photographic plate, thence through a variable width scanning slot and onto a photoelectric detector. Relative scanning motion between beam and slot is effected in directions transverse to slot length. A second beam from the same source is directed around the plate, through the slot and onto the detector. The beams fall on the detector alternately, in synchronism with scanning, so that the second beam produces calibration pulses. Detector output is so amplified as to maintain amplified calibration pulses at constant magnitude.
Abstract:
A component on a frame (2) measures the side angle of the frame, and emits a signal corresp. to it. It also emits a second signal corresp. to the height angle. A second frame (3) fixed to the reference has a sec. angle measurement component which measures the side angle and emits a signal corresp. to it, and a fourth signal corresp. to its height angle relative to the second frame. A length-alterable connecting component (11) is fitted between the angle measuring components, and incorporates a calculating unit (14) which receives all the emitted signals, calculating from them the relative side and height angles of the frames, and thus the direction (20) of the object (1) relative to the reference. The connecting component (11) in the unloaded state crossways takes the form of at least one long, somewhat-cupped strip bendable at right-angles to its longitudinal direction, by overcoming a force which attempts to restore to its unloaded shape.