A serious problem facing the biomedical monitor in the major human body physiological events movement is that of the non-contact requirement in the various measurements. Currently, the most widely used methods to measure the behavior of muscle pulsing are electronic devices or a high speed photography method (Chang et al., 1994). The method of EMG ( electromyogram ) can obtain the muscle potentials; the analysis of scattering of acoustic wave can obtain the tissue motion (Meunier and Bertrand, 1995); CT ( computer topography) can obtain 3D human thorax model ( Jorgenson, 1995); the sphygmomanometer can obtain the blood pressure; EM (electron microscopy) can reconstruct the 3D nerve cell ( Carlboom, 1994); the BSR ( basic skin resistance ) and GSR ( galvanic skin resistance ) can obtain the neurological functions of a muscle pulsing. (However, all the above techniques can not be utilized to measure the displacement of a body with slight movement for whole field monitoring in a meanwhile. Thus an interesting area of development is moire technique as a tool to measure the displacement of skin surface.

The basis of the phase moire-pattern technique is the superposition of a master phase grating and a reference phase grating. We place a phase grating mask on the screen facing a video TV, which not only lets us measure the small displacement of an object which we could not see by video before, but it also gives us real time 3 dimensional data (Agin, 1976). In the meantime we develop an image processing system to analyze the fringes of the moire, and all the necessary information is obtained from the moire fringes by experimental calibration testing and computer image processing. The grating of a moire system can be adaptive using a liquid crystal light projector( Sansoni, 1994), but here we still use a unchangeable one. Fig.1 is the Scheme for image processing analysis in phase moire measurement. Hence measuring techniques suitable for this purpose should provide a signal output allowing on-line computer processing (Cline et al., 1982; Murakami and Murakami, 1978). However, the muscle movement varies rapidly at the instant of body movement. The digital image processing with a projection moire technique which we use is a non-contact measurement method (Fig.2), quick enough to capture and analyze the impulse. This gives a visual demonstration of muscle motion in the whole field.

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