In an image display device that divides one frame into a plurality of fields and performs drive operation, a light-source lighting period with a sufficient length is ensured. In a field-sequential image display device, as modes during writing of data into pixel portions, a normal writing mode for writing data into one row at a time and a high-speed writing mode for writing data having the same value into a plurality of rows at a time for each column are prepared. In a blue field (F(B)), data writing processing in the high-speed writing mode is performed. In a green field (F(G)) and a red field (F(R)), data writing processing in the normal writing mode is performed.

The present invention discloses a Gamma voltage driving circuit, which comprises a voltage dividing resistor string, which comprises 2.sup.n resistors connected in series sequentially, used to divide a reference voltage into 2.sup.n Gamma voltages; wherein, n is an integer not less than 1; a reference voltage module, which provides the reference voltage for the voltage dividing resistor string; a voltage selecting module, which is used to selectively output one of the 2.sup.n Gamma voltages. The reference voltage module comprises a first reference voltage and a second reference voltage, the first reference voltage is coupled to one end of the voltage dividing resistor string, the second reference voltage is coupled between the 2.sup.n/2-th resistor and the (2.sup.n/2+1)-th resistor; wherein, the voltage selecting module comprises 2.sup.n1 transmission lines, which respectively connects the voltage dividing nodes of the first to (2.sup.n/21)-th resistors and the (2.sup.n/2+1)-th to 2.sup.n-th resistors in the voltage dividing resistor string to a output terminal; and each transmission line is provided with n1 switching units.

A dimming device according to the present disclosure includes a dimming panel. The dimming panel includes a dimming layer, a plurality of column electrodes, and a plurality of row electrodes. The dimming layer has a plurality of regions partitioned in a matrix. The column electrodes are arranged in a row direction along a front surface of the dimming layer. Each of the column electrodes extends in a column direction. The row electrodes face the column electrodes with the plurality of regions interposed therebetween and are arranged in the column direction along a back surface of the dimming layer. Each of the row electrodes extends in the row direction. Voltages having substantially the same waveform are supplied to a column electrode and a row electrode corresponding to a region of the regions controlled to a predetermined transmittance, among the column electrodes and the row electrodes.

An object is to reduce parasitic capacitance of a signal line included in a liquid crystal display device. A transistor including an oxide semiconductor layer is used as a transistor provided in each pixel. Note that the oxide semiconductor layer is an oxide semiconductor layer which is highly purified by thoroughly removing impurities (hydrogen, water, or the like) which become electron suppliers (donors). Thus, the amount of leakage current (off-state current) can be reduced when the transistor is off. Therefore, a voltage applied to a liquid crystal element can be held without providing a capacitor in each pixel. In addition, a capacitor wiring extending to a pixel portion of the liquid crystal display device can be eliminated. Therefore, parasitic capacitance in a region where the signal line and the capacitor wiring intersect with each other can be eliminated.