Patent ID: 8487986

Claim:
An impedance matching apparatus comprising: a solid image pickup device; a driving portion that drives the solid image pickup device so that the solid image pickup device outputs a rectangular wave; a cable that transmits the rectangular wave outputted from the solid image pickup device; a correlated double sampling circuit that performs correlated double sampling by fixing a timing of a feedthrough sampling pulse to a timing at which the rectangular wave transmitted by the cable indicates a high value, and with the fixed timing of the feedthrough sampling pulse as a basis, sampling the rectangular wave with a timing of a signal clamp pulse being changed to scan the rectangular wave; a variable resistance provided at a tail end side of the cable and having a variable resistance value; and a resistance value varying portion that based on a signal outputted from the correlated double sampling circuit, changes a resistance value of the variable resistance so that a resistance value of the variable resistance matches a characteristic impedance of the cable.