| 摘要 |
1,008,993. Projection apparatus, electrophotographic processes. RANK-XEROX Ltd. July 27, 1962 [July 27, 1961], No. 28941/62. Headings G2E; G2H and G2J [Also in Division H4] In order to assist recognition of a moving target in a radar xerographic plates are each exposed successively to an image frame on P.P.I. 10, Fig. 1, the plates are developed, the plate images are rapidly projected on to a viewing screen 18 and the plates are cleaned successively and then re-exposed such that they are successively "up-dated". Turret 31, Fig. 2 continuously revolves, arrow B, to advance plates 30 through the xerographic processing station 50 comprising elements 13...16. Projector housing 41 continuously revolves, arrow C, at a much more rapid rate than turret 31. Each plate 10 is capable of xerographic processing on either side, and after development at stage 16 each plate is turned around; each plate comprises a central metal sheet supporting selenium coatings the latter being formed with polished surfaces to afford high reflexion in the projection stage. Each plate must be exposed to P.P.I.10 for complete 360 degrees of radar scan; hence housing 32 is arranged to oscillate, arrow D and to reciprocate, arrow E. Optical projection system, Fig.2. Some light from source 42 via lens 45 is directed to a plate 30 and the reflected image passes via a rotating prism 47, mirror 48, lens 49, Dove prism 60 and mirrors 61, 62 to viewing screen 18. Rotation of prism 47 is such as to result in a stationary optical image during the time of transmission of a given image to mirror 48. To compensate for the relative motion between turrets 31, 40 Dove prism 60 is rotated, arrow G. |
