Patent ID: 7027159

Claim:
A sensor utilizing evanescent wave, comprising: a light source for emitting a light beam; a measuring chip formed into the shape of a well and comprising a dielectric block transparent to said light beam, a thin film layer formed on one surface of said dielectric block, and a sample holding mechanism for holding a sample on a surface of said thin film layer; an optical system for making said light beam enter said dielectric block at angles of incidence so that a total internal reflection condition is satisfied at an interface between said dielectric block and said thin film layer; photodetection means for detecting the intensity of said light beam totally reflected at said interface; and measurement means for measuring a state of attenuated total reflection, based on the result of detection obtained by said photodetection means; wherein said sensor further comprises sample supply-discharge means, which is detachably installed within said measuring chip, for continuously supplying said sample onto the surface of said thin film layer and continuously discharging the supplied sample from the surface of said thin film layer.