Method for driving semiconductor device

摘要

A semiconductor device capable of acquiring high-precision range information in a short time is provided. Alternatively, a semiconductor device capable of acquiring the range information and image information concurrently in a short time is provided. The accuracy of range information is increased by performing infrared light irradiation more than once to acquire a detection signal and making infrared light irradiation periods identical and extremely short. By detecting light reflected from substantially the same points of an object by adjacent photodiodes, the accuracy of range information can be maintained even when the object is a moving object. By overlapping a photodiode absorbing visible light and transmitting infrared light with a photodiode absorbing infrared light, range information and image information can be acquired concurrently.

主权项

1. A method for driving a semiconductor device comprising a photosensor comprising a photodiode, comprising the steps of:
performing first reset operation by supplying a first signal to a first terminal of the photodiode from a first time to a second time; performing first irradiation of an object with first light from a light source from the second time to a fourth time; performing first imaging by detecting the first light reflected off the object from the second time to the fourth time; repeating the first irradiation and the first imaging n (n is a natural number of 2 or more) times; performing second irradiation of the object with second light from the light source from a twelfth time to a fifteenth time; performing second reset operation by supplying the first signal to the first terminal of the photodiode from a fourteenth time to the fifteenth time; performing second imaging by detecting the second light reflected off the object from the fifteenth time to a sixteenth time; and repeating the second irradiation and the second imaging the n times, wherein a time length from the second time to the fourth time and a time length from the twelfth time to the fifteenth time are the same.