A time to digital converter has a counter to measure the number of cycles of a first signal, a first phase difference detector to generate a phase difference signal having a pulse width corresponding to a phase difference, a first capacitor to be charged with an electric charge, a second capacitor including capacitance N times the capacitance of the first capacitor, the N being a real number larger than 1, a comparator to compare a charge voltage of the first capacitor and a charge voltage of the second capacitor, a first charge controller to continue to charge the second capacitor until the comparator detects that the charge voltage of the second capacitor has reached the charge voltage of the first capacitor or more, and a first phase difference arithmetic unit to operate the phase difference between the first signal and the second signal.