Figure 32

Figure 32: Example of an error signal: the top graph shows the electronic interferometer output signal as a function of mirror displacement. The operating point is given as the zero crossing, and the error-signal slope is defined as the slope at the operating point. The right graph shows the magnitude of the transfer function mirror displacement → error signal. The slope of the error signal (left graph) is equal to the low frequency limit of the transfer function magnitude (see Equation (102View Equation)).