“…In the range of memory effect, each time the target point moves by two pixels. Thus, the 8 focal points are adjacent on the CCD screen, where the central coordinates of the focal points are [20,40], [20,42], [20,44], [20,46], [20,48], [20,50], [20,52], and [20,54], respectively. We integrate the intensity of 3 × 3 pixels around the central points to save in a computer as the feedback signal to control the spatial light modulator.…”