In this paper we present the method for fast computer generation hologram (CGH) of the long depth object using multiple wavefront recording planes (WRP). The wavefront recording planes are placed between object plane and hologram plane. Each WRP records the wavefront from a section of object. For a long depth object, multiple WRPs can reduce the calculation time and also enhance the quality of reconstruction object in comparison with those ones of single WRP. The hologram of object can be real time generated by out proposed method.
In this paper, we present an analysis on space bandwidth product of digital hologram. The condition for clear
reconstruction of in-axis and off-axis digital hologram case is derived. The correlation efficiency and modulate transfer
function (MTF) are then used for quantitative analysis of the reconstruction object. The presented analysis is verified by
simulation result and then is applied to record and reconstruct video hologram.
In this paper, we use multi-point source illumination to enhance the resolution of digital holographic microscopy without
shifting the CCD camera. The specimen is illuminated from many directions by using multi-point sources which are
easily created by a lens-array. The high frequency information of the specimen can be captured at a fixed position of
CCD camera. All information is then synthesized to increase the resolution.
In this paper, the input-output coupler system using two and three Bragg gratings is implemented for optical communication wavelength, i.e. 1550nm, in path-folding and path-shifting type. The grating is designed with 45 degrees fringe slant angle to achieve normal direction input, output coupler. An additional grating at the output coupler makes the total system throughput increase 9% in comparison with two-grating input-output coupler system. With 5x5mm grating size, the total systems throughput can reach nearly 26% for two-grating and 35% for three-grating input-output coupler.