In-line digital holography for high speed 4D tracking of particles

A setup and algorithm for 4D tracking of microscopic particles are considered. The algorithm is implemented with a commercial parallel computing technology (CUDA) which increases dramatically the speed of digital video hologram processing. The system can measure the number, 3D position, size, speed and track of the particles. The experiments show that the variance of the imaginary part of complex amplitude has unambiguous dipping characteristics near the true depth position of the particle thus providing means to significant improvement in depth resolution.