Patent ID: 8842286

Claim:
A method for controlling a fiber-optic Sagnac interferometer, comprising a light source, a polarizer, a fiber coil, a photodetector device, an amplifier comprising an analog/digital converter connected downstream, a digital/analog converter, an evaluation circuit and an adder, wherein two light beams, which originate from the light source, which are polarized by the polarizer and which are created by means of a beam splitter, are irradiated into the fiber coil in opposite directions and are recombined subsequently, an interference signal, which is created from the recombination of the light beams, is applied to the photodetector device after passing through the polarizer, wherein a signal which corresponds to the light intensity of the interference signal and which is applied to the amplifier comprising the analog/digital converter connected downstream, the output signals of which are processed in the evaluation circuit, is supplied by means of the photodetector device, and wherein a digital phase resetting signal is created with the help of a main control circuit of the evaluation circuit and is supplied to the digital/analog converter for obtaining a resetting signal, which acts on the phase modulator, characterized in that: the output of the analog/digital converter and thus the output signals, which are processed in the main control circuit, as well as the phase resetting signal, encompass a first word width, and the input of the digital/analog converter and thus the resetting signal, which acts on the phase modulator, encompasses a second word width, which is smaller than the first word width, with which the modulation and resetting signal are computed in the digital part of the main control circuit, wherein a residual value signal comprising a third word width, which can be added via the adder to the output signal of the analog/digital converter is created wherein this third word width corresponds to a number of surplus low-value bits, which are computed by the evaluation circuit but which cannot be applied to the digital/analog converter, because it only encompasses a limited, smaller word width.