Multi-plane unequal interval imaging based on polarization multiplexing

We propose an approach for imaging multi-plane-object where the image contents at different distant planes are recorded simultaneously in a single shot. The method is based on a compound quadratic distorted (QD) grating and the polarization multiplexing technique. The compound grating consists of two QD gratings with different parameters, which controls the distance interval between object planes. In polarization multiplexing technique, the images on x- and y- directions are modulated into orthogonally polarized, therefore the desired images can be selected by rotating the analyzer in the system. Two experiments are carried out to verify the proposed method. The first experiment is for the static samples, in which the distance interval between adjacent imaging planes can be changed from mm to μm by controlling the parameters of two QD gratings and magnification of the imaging system. The second experiment is the imaging of dynamic samples of flowing yeasts in microfluidic tubes. From the recorded data, we calculate the velocity of flow particles. Both experimental results prove that the proposed method is capable of imaging 3D object consisting of unequal-distance-layers, which is of significance for potential applications in particles imaging and tracking.