Patent ID: 8690278

Claim:
A wiring substrate unit which is connected to a signal supply portion and through which a signal is transmitted to a drive object, comprising: a first wiring substrate through which the signal is transmitted to the drive object; a second wiring substrate which is stacked on the first wiring substrate and through which the signal is transmitted to the drive object; a first input portion which includes a plurality of first input terminals formed in an end portion of the first wiring substrate and which is connected to the signal supply portion; a second input portion which includes a plurality of second input terminals formed in an end portion of the second wiring substrate and which is connected to the signal supply portion; a plurality of first output contact points which is formed on one surface of the first wiring substrate and which is electrically connected to the first input portion; and a plurality of second output contact points which is formed on one surface of the second wiring substrate and which is electrically connected to the second input portion; wherein the first wiring substrate and the second wiring substrate are stacked so that the other surface of the first wiring substrate faces the one surface of the second wiring substrate; wherein a through hole, which is configured to electrically conduct the second wiring substrate and the drive object, is formed in the first wiring substrate to correspond to the second output contact points formed on the second wiring substrate; wherein a cutout is formed at a position adjacent to the first input portion of the end portion of the first wiring substrate or at a position adjacent to the second input portion of the end portion of the second wiring substrate; wherein one of the first input portion of the first wiring substrate and the second input portion of the second wiring substrate is exposed from the cutout; wherein the wiring substrate unit further comprises a driver IC which is installed on one of the first and second wiring substrates; wherein the cutout is formed on the other of the first and second wiring substrates; and wherein the driver IC is arranged at an end portion of the one of the first and second wiring substrate so that the driver IC is exposed from the cutout.