| 摘要 |
<p>PURPOSE:To transmit a brightness signal and two color difference signals by one pulse string by successively executing the pulse width modulation of a component video signals at the rate of a brightness signal, a 1st color difference signal, a brightness signal, and a 2nd color difference signal. CONSTITUTION:A saw tooth wave generating circuit 12 outputs a saw tooth wave signal (d) and a comparator 13 compares the amplitude value of the signal (d) with that of a Y signal, and at the time of coincidence of both the signals, outputs a trigger pulse (e). A saw tooth wave generating circuit 21 outputs a saw tooth wave signal (h) and a comparator 22 compares the amplitude value of the signal (h) with that of a PR signal, and at the time of coincidence, outputs a trigger pulse (i). A saw tooth wave generating circuit 30 outputs a saw tooth wave signal (j) having a phase different from the phase of the signal (i) by 180 deg. and a comparator 31 compares the amplitude value of the signal (j) with that of a PB signal, and at the time of coincidence, outputs a reset pulse (k). Finally, an adder 40 adds the trigger pulses (e), (i), (k) and outputs an added signal 1. Thus, pulse light transmission can be attained by one light emitting element and one pulse string information independent of linearity.</p> |
