PHOTODETECTOR DEVICE

A photodetector device 1 includes an avalanche photodiode array substrate 10. A circuit substrate 50 includes time measurement circuits 40 and a clock driver 35. Each of the time measurement circuit 40 includes a delay line unit, and is arranged to acquire, from an operation result of a delay line 47, time information indicating timing at which a pulse signal is input from a corresponding avalanche photodiode 20. The delay line unit is arranged to initiate an operation of the delay line 47 in response to input of the pulse signal to the time measurement circuit 40, and to stop the operation of the delay line 47 in response to input of a clock signal from a clock driver 35 to the time measurement circuit 40, and is arranged to detect a time interval shorter than a cycle of the clock signal by the operation of the delay line 47.