Light valve device with failure detection circuit.

摘要

Pixels, which include both thin-film type transistors (1) and liquid crystal cells (3) driven by liquid crystal driving electrodes, are arranged in a matrix shape together with image signal lines (4) and control signal lines (5) connected to each of the transistors. A control signal line driving circuit (6) is formed of shift registers having one bit per signal line, and data signals inputted on scanning-start, synchronised with the clock signal. The driving circuit outputs the signals capable of turning-ON the thin-film transistor of the corresponding control signal line from a shift register on a position which is moved by one bit per every clock cycle. A detecting circuit (9) of the image signal line driving circuit (8) have three terminals, the first terminals are connected to the image signal lines (4), the second terminals are connected to output lines (10), and the third terminals are connected to outputs (11) of the shift registers, so that failures of the driving circuits can be detected simply. <IMAGE>