Fig. 1. Principle used in the FEDA to focus scattered light. (a)–(e) Procedure of phase modulation of four elements. (f)–(j) Procedure of phase modulation of 16 elements. M means to modulate these elements cycling from 0 to 2π; 0 represents the part that stays the same with the original wave; B is the element of the optimized phase of the elder generation; b is the element of the optimized phase of the filial generation.

Fig. 2. Setup used to focus light through turbid media. M is a mirror; O1, O2, and O3 stand for microscope objectives; L1, L2, and L3 are lenses with a focal distance of 75, 300, and 100 mm, respectively; S represents the turbid medium or the ground glass; PC, personal computer.

Fig. 3. Experimental enhancement of the three algorithms with respect to measurement times at the element number of 4096. (a) SSA with an iteration of four times, (b) CSA with an iteration four times, (c) FEDA.

Fig. 4. Optimized phase distribution and transmission images by wavefront shaping. (a) The phase distribution of plane wave, (b) the transmission image through the sample with plane waves, (c) the modulated phase distribution using SSA (after an iteration of four times), (d) the focusing on the CCD using SSA, (e) the modulated phase distribution using CSA (after four iterations), (f) the focusing on the CCD using CSA, (g) the modulated phase distribution using FEDA, and (h) the focusing on the CCD using FEDA.