Patent ID: 7233399

Claim:
A method for controlling an interferometer, comprising the steps of: receiving a modulated optical signal, guiding the modulated optical signal to an input of the interferometer, splitting the modulated optical signal into a first and a second optical partial signal, guiding the first optical partial signal in a first line, guiding the second optical partial signal in a second line, wherein the second optical partial signal is delayed by a variable delay time τ with respect to the first optical partial signal, generating a first and a second optical output signal of the interferometer by coupling of the first and the second optical partial signals, transforming the first optical output signal of the interferometer into a first electrical signal, transforming the second optical output signal of the interferometer into a second electrical signal, generating a third electrical signal depending on the first and the second electrical signals, generating a feedback signal depending on the third electrical signal, feeding the feedback signal into the interferometer, and adjusting the delay time τ depending on the feedback signal, wherein said generating the feedback signal comprises processing an additional signal, which is generated by separate means and contains information about the quality of the phase tuning of the interferometer.