Abstract: An active-matrix liquid crystal display has a drive circuit for driving thin-film transistors. The drive circuit comprises a shift register transmitting a sequence of image data for a single scanning line, latch circuits, tristate output circuits, pixel electrodes, and switching devices each turning on and off a pixel electrode. Each tristate output circuit has an control terminal and an input terminal. When the level of a image data received by the control terminal is high, the tristate output circuit, in response to a high or low potential of a frame signal received by the input terminal, outputs a high or low potential respectively different from those of the frame signal. The switching devices enable the output potential of each tristate output circuit to be charged in the pixel electrodes. During the charge time, the shift register transmits a next sequence of image data.

Abstract: A thin film transistor includes a gate insulating film, a plurality of gate electrodes arranged on one surface of the gate insulating film, and a thin film semiconductor island formed on the other surface of the gate insulating film and having portions each corresponding to one of the gate electrodes. The island includes a source region in which ion impurities are diffused at high density and located at one end of the island, a drain region in which ion impurities are diffused at high density and located at the other end of the island, a first low impurity region in which ion impurities are diffused at lower density than that of the drain region and located between the drain region and one of the portions adjacent to the drain region, and a second low impurity region in which ion impurities are diffused at lower density than that of the drain region and located between at least one of the portions.