Patent ID: 7245143

Claim:
An electro-optical device comprising: a first substrate; a first IC that is mounted on the first substrate and that has a plurality of first terminals; a plurality of second terminals formed on the first substrate to be connected to the first terminals; a plurality of wiring lines formed on the first substrate; a pair of first-substrate crack diagnostic terminals that are included in the first terminals and that are used for diagnosing whether a crack occurs in the first substrate; a pair of second-substrate crack diagnostic terminals that are included in the second terminals and that are connected to the pair of first-substrate crack diagnostic terminals; a substrate crack diagnostic conductive pattern that is electrically connected to each of the pair of second-substrate crack diagnostic terminals and that extends around an outer periphery of the first substrate; a substrate crack diagnostic unit provided in the first IC to diagnose whether the pair of first-substrate crack diagnostic terminals are electrically connected to each other; and a substrate crack diagnosis result output unit provided in the first IC to output a diagnosis result diagnosed by the substrate crack diagnostic unit.