| 摘要 |
<p>The film projection section is for a telecine unit which can replay both 18 and 24 frame per second films without causing flicker of strobing on the TV picture. The method uses clock pulses synchronisation between the TV field frequency and projector shutter, to avoid using expensive polygonal shutter units, and also avoids sound track speed alterations of 7 and 4% for 18 and 24 f.p.s. replay respectively. The equipment uses a claw drive film transport and fade-out diaphragm. The diaphragm produces a pulse signal from which a correction signal (KBS) is derived to control the TV picture. The method is suitable for single, double, triple or four bladed shutters and by comparing the shutter/apeture frequency with the picture frequency of the TV a sawtooth correction signal is produced to synchronise TV scan with picture exposure for exposure durations which compensate for the different f.p.s. rates between projector and TV.</p> |
