Patent ID: 8106900

Claim:
A control method for an information display device including: a display having a data line applied with a data voltage, a switching element having a first input terminal connected to the data line and a first output terminal for turning on and off a signal between the first input terminal and the first output terminal, a latch circuit having a second input terminal connected to the switching element and a second output terminal for holding a voltage according to a data voltage input from the switching element via the second input terminal and for outputting the held voltage, a pixel electrode connected to the second output terminal, a common electrode, and a memory type electro-optical layer interposed between the pixel electrode and the common electrode; a display driving circuit for driving the display; and a power control circuit for controlling the supply of power to the latch circuit and the display driving circuit, the control method comprising: stopping, by the power control circuit, the supply of power to the display driving circuit; stopping, by the power control circuit, the supply of power to the latch circuit; supplying, by the power control circuit, power to the display driving circuit after the supply of power to the display driving circuit and the latch circuit is stopped; applying, by the display driving circuit, a first voltage to the common electrode after power is supplied to the display driving circuit; applying, by the display driving circuit, a second voltage, which is different from the first voltage and varies a potential of the pixel electrode according to a charge state of the memory type electro-optical layer, to the common electrode after the first voltage is applied; applying, by the display driving circuit, a third voltage, which is a voltage between the first voltage and the second voltage, to the common electrode after the second voltage is applied; and supplying, by the power control circuit, power to the latch circuit after the third voltage is applied.