The semiconductor device includes a first photodiode, a second photodiode which is shielded from light, a first circuit group including a voltage follower circuit, a second circuit group, and a compensation circuit, in which an output from the first photodiode is inputted to the voltage follower circuit of the first circuit group, an output from the first circuit group is inputted to the compensation circuit, and an output from the second photodiode is inputted to the compensation circuit through the second circuit group. By adding or subtracting these inputs in the compensation circuit, an output fluctuation due to temperature of the first photodiode is removed. Note that a reference potential is supplied to the first photodiode so that an open circuit voltage is outputted, and a potential is supplied to the second photodiode so that a forward bias is applied to the second photodiode.