Abstract: This invention, which comprises a cuff, an exhaust portion, a pressure sensor, an A/D converter, a microcomputer, a display, and an operation portion, initially determines the maximum pulse wave amplitude by comparing the size of each pulse wave, and it then determines the maximum pulse wave amplitude by comparing the sizes of the values obtained by totalling each pulse wave amplitude along with its preceding and subsequent pulse wave amplitudes, and it finally determines the maximum pulse wave amplitude by evaluating whether the different value between each preceding and each subsequent pulse wave amplitudes which occur after the maximum pulse wave amplitude has a negative(-) sign, thereby eliminating erroneous calculations caused by oscillation noise interference.

Abstract: An improved device for modulating the intensity of a light beam is described which comprises a first isoceles optical prism; a first dielectric layer, a thin metallic layer, and a second dielectric layer substantially identical in composition and thickness to the first dielectric layer deposited successively on the base of the first prism; a second isoceles optical prism disposed with the base thereof contacting the last deposited layer; and a controllable source of electrical current connected to the metallic layer for establishing and modulating an electro-magnetic field at the respective surfaces of the metallic layer.