| 摘要 |
<p>PURPOSE:To hold all of the beneficial points of a non-contact system and to easily reduce a spot diameter because of an optical system, by detecting the displacement of the reflected beam spot responding to the displacement of the surface of the body. CONSTITUTION:An operation part 5 calculates the polar coordinates positions r, theta, psiof a scattering plate 2 and calculates the polar coordinates positions r', theta', psi' of the scattering plate 2 in such a state that the position of the second beam spot position sensor 4 is set to the origin so that said sensor 4 performs automatic tracking. A drive part 4b allows the second beam spot position sensor 4 to respond in correspon dence wit the polar coordinates signal thereof to allow scattering beam to be incident in sufficient quantity. The incident position of the beam spot thereof to the beam spot position sensor 4 displaces with the variation of a reflecting position corresponding to the displacement of the surface of the body due to respiration or heart beat and is detected with high sensitivity by an optical system having a long focal distance. A body surface displacement wave form detection circuit 6 detects a desired body surface displacement wave form containing no noise from the detection signal of said sensor and the output signal thereof is counted with respect to a predetermined time by a body surface displacement number-of-time count circuit 7.</p> |
