| 摘要 |
1,158,282. Photo-electric telemetry. JOS. SCHNEIDER & CO. OPTISCHE WERKE. Oct. 3, 1966 [Oct. 2, 1965], No.44074/66. Heading G1A. [Also in Division G2] Apparatus for detecting the position of an indicator comprises a light guide mounted on the indicator for rotation therewith, a fixed light guide defining a reference position and a constantly rotating light guide which aligns with each of the other light guides once per rotation. Light from source 7 passes along a fixed fibre optic light guide 9 and a fibre optic light guide 2 on a rotary indicator 1. The light from these guides is picked up by a fibre-optic light guide 5 on a motor driven mounting 3 and passed to a photodetector 8 to produce pulses. The relative phase of which indicates the indicator position. The phase may be measured by analogue or digital means e.g. a counter. In a modification, Fig. 3 light from source 7 passes along a light guide 12 through the axis of motor 4 and passes to reference and indicator light guides 9, 2. The indicator light pulse passes along guide 11 coaxial with guide 5 to detector 8, the reference pulses being generated by detector 8a. In a modification, Fig.2 (not shown) source 7 is replaced by a detector and detectors 8, 8a by one or two sources. Where light guides are coaxial as at E5/A11 and A12/E13, cross-talk due to reflections of the faces is prevented by arranging the end faces of the inner and outer guides in different planes, Fig. 4 (not shown). |
