PURPOSE: To obtain the optimum shift register for picture display by arranging master and slave blocks in series each comprising 4 sets of inverters and 7 sets of transmission gates to attain two-way left/right shift.

CONSTITUTION: The master and slave blocks comprising 4 inverters 101W104 and 7 transmission gates 105W111 are connected in series via agate 108, and when the level of a clock goes to H, a gate 105 is turned on and data is latched in the master block by an inverter 101. When the clock goes to L, gates 107, 108 are turned on and the data shifted right is latched via an inverter 103 of the slave block. When the clock goes to H, the data shifted to the right is outputted via gates 100, 111. Similarly, the shift left is attained, two-way shift is applied, and even when a picture is reflected in a mirror or viewed from the back side, no inversion of upper/lower/left/right of the picture takes place and a shift register optimum to the picture display is obtained.