A signal source synchronization circuit comprising: a reference signal source that generates a reference signal; a first signal source circuit that adjusts a phase of the reference signal generated by the reference signal source and generates a signal synchronized with the reference signal after the phase adjustment; a second signal source circuit that adjusts a phase of the reference signal generated by the reference signal source and generates a signal synchronized with the reference signal after the phase adjustment; a trigger signal generation circuit that outputs a trigger signal; a first time difference measurement circuit that has a first input terminal (a) to which the trigger signal outputted from the trigger signal generation circuit is directly inputted and a second input terminal (b) to which the trigger signal outputted from the trigger signal generation circuit and then fed back via the first signal source circuit is inputted, and measures a time difference between an input time of the trigger signal to the first input terminal (a) and an input time of the trigger signal to the second input terminal (b); and a second time difference measurement circuit that has a first input terminal (a)to which the trigger signal outputted from the trigger signal generation circuit is directly inputted and a second input terminal (b) to which the trigger signal outputted from the trigger signal generation circuit and then fed back via the second signal source circuit is inputted, and measures a time difference between an input time of the trigger signal to the first input terminal (a) and an input time of the trigger signal to the second input terminal (b), wherein the first signal source circuit adjusts the phase of the reference signal according to the time difference measured by the first time difference measurement circuit, and the second signal source circuit adjusts the phase of the reference signal according to the time difference measured by the second time difference measurement circuit. a reference signal source that generates a reference signal; a first signal source circuit that adjusts a phase of the reference signal generated by the reference signal source and generates a signal synchronized with the reference signal after the phase adjustment; a second signal source circuit that adjusts a phase of the reference signal generated by the reference signal source and generates a signal synchronized with the reference signal after the phase adjustment; a trigger signal generation circuit that outputs a trigger signal; a first time difference measurement circuit that has a first input terminal (a) to which the trigger signal outputted from the trigger signal generation circuit is directly inputted and a second input terminal (b) to which the trigger signal outputted from the trigger signal generation circuit and then fed back via the first signal source circuit is inputted, and measures a time difference between an input time of the trigger signal to the first input terminal (a) and an input time of the trigger signal to the second input terminal (b); and a second time difference measurement circuit that has a first input terminal (a)to which the trigger signal outputted from the trigger signal generation circuit is directly inputted and a second input terminal (b) to which the trigger signal outputted from the trigger signal generation circuit and then fed back via the second signal source circuit is inputted, and measures a time difference between an input time of the trigger signal to the first input terminal (a) and an input time of the trigger signal to the second input terminal (b), wherein the first signal source circuit adjusts the phase of the reference signal according to the time difference measured by the first time difference measurement circuit, and the second signal source circuit adjusts the phase of the reference signal according to the time difference measured by the second time difference measurement circuit.