Time-axis picture-signal converter for facsimile and the like

A time-axis converter for a facsimile or the like appartus of the type in which a high-speed analog picture signal from a solid-state image sensor consisting of a succession of one-line segments each including a blanking period is converted by means of an analog memory device into an analog picture signal of one-scan line suited to the transmission rate of the circuit line, said converter being characterized in that it comprises:

• first clock means for producing a high-speed clock of the rate corresponding to the picture-signal output rate of the solid-state image sensor;
• second clock means for producing a low-speed clock of the rate corresponding to the transmission rate of the circuit line;
• first counter means for counting the high-speed clock pulses from said first clock means and adapted to be reset at a specified full count;
• second counter means for counting the low-speed clock pulses from said second clock means and adapted to be reset at the same full count as that of said first counter means;
• means for producing a switching signal each time the output indications of said first and second counter means coincide with each other;
• a pair of analog memory devices having a predetermined number of memory elements for delaying and expanding said high-speed analog picture signal;
• means for distributing said high-speed picture signal alternately to one and the other of said analog memory devices under the control of said switching signal;
• means for reading out the output signal of said analog memory devices alternately under the control of said switching signal as the distribution of said high-speed picture signal to one or the other of said analog memory devices is interrupted;
• and
• shift-pulse feeding means coupled to each of said analog memory devices for shifting the contents of the memory elements of the analog memory device alternately at the rates of the high-speed and low-speed clocks, the switching between the high-speed and low-speed clocks being effected under the control of said switching signal from the high-speed to the low-speed clock each time the supply of said high-speed picture signal to the analog memory device is started and from the low-speed to the high-speed clock each time such signal supply to the analog memory device is interrupted.