| 摘要 |
1,183,265. Recording and playback. THOMSON-CSF. 10 Feb., 1967 [11 Feb., 1966], No. 6595/67. Heading G5R. [Also in Division G2] Apparatus for recording a plurality of holograms in superposition on a sensitive surface 4 in which the objects I 1 , I 2 , I 3 , I 4 . . . to be recorded are photographic transparencies on a support 18 and may be successive frames of a cine film, comprises a laser 1 giving a reference beam F 2 and an illuminating beam F 3 which passes through a transparency to be recorded and is brought to interfere with the beam F 2 at the surface 4. The support 18 is moved intermittently by mechanism 19 through the field of the beam F 3 , while mechanism 20, driving in synchronism with mechanism 19, intermittently alters the orientation of the surface 4 to provide a different inclination thereof for each object recorded. In one embodiment for reading the holograms stored on the surface (4) (Fig. 4, not shown), the surface is intermittently rotated by mechanism (23) similar to the mechanism 20, and the images so obtained viewed through a collimator. Alternatively, the image is formed on a layer of photosensitive material of a picture analyser tube (24) (Fig. 5, not shown) which is scanned to supply a video signal which can be used in a conventional television receiver. The recording and reproduction of television pictures may also be effected by recording the video signal used for transmission directly as a hologram (Figs. 6, 7, not shown). The signal is applied through a synchronizer separator (28) to an optical modulator (18) while a synchronization signal S controls the orientation mechanism, the orientation being changed with each change in the brightness value of a light spot (I), changes being proportional to those in the video signal. The readout system (Fig. 7) additionally comprises a photosensitive cell (31) receiving the image (I<SP>1</SP>) of the light spot (I) The electric signal from the cell (31) is applied to an amplifier (30) which thus gives the video signal at its output. |
