Fig. 9.13 — Cross-correlation function and crosstalk reduction

Cross-correlation function and crosstalk reduction. (a) Cross-correlation function (CCF) between the QPD signals x_qpd and y_qpd (black solid line), autocorrelation function (ACF) of x_qpd (grey solid line) and ACF of y_qpd (dashed solid line). Inset: the probability distribution of xqpd and yqpd is an inclined elliptical Gaussian distribution. (b) CCF between the decorrelated signals x_qpd′ and y_qpd′ (black solid line) is close to zero and coincides with the x-axis in the graph. ACF of x_qpd′ (grey solid line) and ACF of y_qpd′ (dashed solid line). Inset: the major axes of the probability distribution of x_qpd′ and y_qpd′ coincide with the coordinate axes.