Method and apparatus for in vitro or in vivo measurement of a concentration of a component

摘要

A method and an apparatus for measuring a concentration of a component in a subject, e.g., glucose in blood, are described. The apparatus comprises a light source (111) for generating light having a first wavelength band; a tunable filter (114) and a radio frequency (RF) generator (113) operatively connected thereto, said tunable filter being arranged to receive the light having the first wavelength band and to generate a positive-order beam (115) and a negative-order beam (117) having a second wavelength band according to a radio frequency signal provided by the RF signal generator; a first light detector (122) for detecting a first output beam reflected from or transmitted through the subject (120); a second light detector (123) for detecting a second output beam reflected or transmitted from a reference matter (121); and a signal processor (126) provided with an intensity relationship equation between the positive-order beam and the negative-order beam and arranged to calculate an intensity of the positive-order beam input to the subject by applying the detected intensity of the second output beam from the reference matter to the intensity relationship equation, to calculate an absorbance using the detected intensity of the first output beam from the subject and the intensity of the positive-order beam input to the subject, and to calculate the concentration of the component using the absorbance.