JPS55117379A - Double-color facsimile device - Google Patents

Abstract

PURPOSE:To transmit simultaneously both the black and red reading signals and then realize the regeneration of these signals, by controlling the analog switch with the red signal and then forming the ternary analog signal including the double-color information. CONSTITUTION:The red beam transmits through half mirror 4 and is then introduced to photoelectric converter 5A to be turned into red picture signal (a). The beams other than the red one are reflected to be turned into picture signal (b) at photoelectric converter 5B. Both signals (a) and (b) are supplied to adder circuit 6 and subtractor circuit 7, and full band picture signal (c) and red picture signal (d) are delivered through circuits 6 and 7 respectively. Signal (c) is divided into two parts; and one part emerges at selected terminal 14 of analog switch 10 via inverter circuit 9 and the other part emerges directly at the other terminal. Here signal (d) selects terminal 14 via selection terminal 16 in the case of plus (+) and then selects selected terminal 15 in the case of 0 each. Accordingly, ternary analog signal (e) is obtained at terminal 16 including the signals obtained by inverting signal (b) at the plus (+) side and signal (d) at the minus (-) side each centering on reference voltage level 0. Then the bias is applied to signal (e) to produce signal (f), and signal (f) is modulated through ring modulator 12 and via the signal sent from pulse oscilator 13. And signals of phases of 0 are pi are obtained according to the plus and minus of signal (f).