| 摘要 |
A bidirectional shift register capable of performing a stable shift operation in both directions and an image display device using the same are provided. In forward shift operation, when reference point N1 is at H level, (n+4)-th unit register circuit as a rear stage of the bidirectional shift register outputs pulse G(n+4) in synchronization with clock pulse V (n+4) inputted to (n+4)-th unit register circuit. A backward direction trigger signal VSTB is generated not only at the time of start of backward shift, but also, for example, in period (time t4 to t5) of one-phase clock immediately after G(n+4) is outputted in vertical blanking interval of the forward shift. The backward direction trigger signal VSTB is inputted to gate of a transistor provided to set reference point N1 of (n+4)-th unit register circuit to H level at the time of start of the backward shift. |
