Pulse generation from 04 Laser beams is of a particular interest on the study of fast or arbitrarily moving objects as in biology and medicine. A hybrid system has been developed to generate a set configuration of pulses with: i) control over the number of pulses; ii) presetting of the individual pulse width and pulse separation; iii) synchronization of the pulse set (either interlaced TV synchronism or other external signal). The control and shaping of the pulses is based on a microprocessor that drives a modulator of high extinction ratio. The system allows the implementation of the twin pulse illumination technique previously described with particular interest to the observation of anisotropy in phase velocity propagation. This has been applied to the examine of bone heterogenety both in macerate and fresh bone and fracture mechanism. It is also belived that wearing, delamination, crack detection,and fluid or heat transport phenomena can be studied. The design of the system was inicially mainly intended for E.S.P.I. but certain advantages have been found in its use in holography. Versatility of the system was introduced in view of exploring other features and applications. This includes other pulse combinations, in particular, triple pulse, and time lapse TV target scanning suppression for slow motion objects and low light levels. Details of the system conception hardware and prospects on the system application in E.S.P.I. and Holography will be discussed with consideration of the main advantages and limitations.
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