An electrooptical device includes a substrate that holds an electrooptical
substance, a first substrate line and a second substrate line provided on
the substrate, a semiconductor device provided on the substrate, a first
input bump and a second input bump provided on a surface of the
semiconductor device, the surface being close to the substrate, an output
bump provided on the surface of the semiconductor device to be connected
to the first substrate line, a base material mounted on the substrate, a
first line provided on the base material to be electrically connected to
the first input bump, and a second line provided on the base material to
be electrically connected to the second input bump via the second
substrate line.