Patent ID: 7777865

Claim:
A time difference measuring device which measures a time difference of two or more pulse signals generated with a predetermined time difference, the time difference measuring device comprising: a reference signal generation unit configured to generate reference signals having a phase difference of approximately π/2; an amplitude detection unit configured to obtain two amplitudes based on the reference signals so as to be substantially equal to sampling the reference signals, at predetermined two timings which depend on generation timings of each of the pulse signals; a phase difference detection unit configured to calculate a phase difference of the generation timings of the pulse signals, on the basis of amplitudes of the two reference signals at each of the generation timings of the two pulse signals, detected by the amplitude detection unit, and on the basis of a ratio of amplitudes of the reference signals; and a time difference calculation unit configured to calculate a generation time difference of the pulse signals on the basis of the phase difference detected by the phase difference detection unit and a cycle of the reference signals.