| 摘要 |
PURPOSE:To correct the dynamic range of the film signal so that it may agree with the dynamic range of the television signal, by controlling directly the luminance of the output light of the flying spot scanning tube. CONSTITUTION:The light flux for scanning generated from flying spot scanning tube 10 is focused on cinefilm 12. This light flux for scanning has the light intensity modulated according to the video pattern recorded on frames of film 12, and this modulation light is input to film image transmitter 15 through condenser lens 13. Image transmitter 15 separates the modulation light into red, blue, and green lights, and further, R, B and G chromaticity signals are output. A part of R, B and G signals is synthesized at a fixed ratio through resistances 16-18 for balance adjustment, and this synthesized signal is fed back to the cathode of flying spot scanning tube 10 through amplifier 19 and clamping circuit 20. By giving the luminance signal to the cathode of flying spot scanning tube 10 in this manner, the output light of scaanning tube 10 is controlled with feedback by the luminance signal to control the luminance in the direction where the transmitting output of film 12 is weakened. |
