Fig. 4.

(a)Reconstruction depths of 9 sources using 14 different DOT channel length thresholds under noise-free condition. Black stars represent selected sources and corresponding optimal DOT channel lengths for curve fitting. (b) Reconstruction depths under low-level noise condition. (c) Reconstruction depths under high-level noise condition. (d) Fitted exponential decay curve using 4 selected DOT channel length thresholds and corresponding standard deviations under noise-free condition. (e) Fitted exponential decay curve under low-level noise condition. (f) Fitted exponential decay curve under high-level noise condition.