Patent ID: 6847835
Filing Date: 2005-01-25
Classification: A61B

Abstract:
1. A bilirubin concentration measuring apparatus, comprising: (a) a light emitter for emitting a light which includes a first luminous flux falling in a first wavelength range and a second luminous flux falling in a second wavelength range, their bilirubin absorption coefficients differing from each other; (b) a light emerging port for projecting the light including the first and second luminous fluxes from the light emitter onto skin of a person for entering thereinto; (c) a first light incident port for allowing the first and second luminous fluxes having been diffused in tissues of the person to pass therethrough; (d) a second light incident port for allowing the first and second luminous fluxes having been diffused in tissues of the person to pass therethrough, the second light incident port being spaced away from the light emerging port a different distance than the first light incident port, so that optical path length of luminous fluxes which pass through the first light incident port and optical path length of luminous fluxes which pass through the second light incident port are different from each other; (e) a first electric signal generator for generating a first electric signal corresponding to an intensity of the first luminous flux passed through the first light incident port, and a second electric signal corresponding to an intensity of the second luminous flux passed through the first light incident port; (f) a second electric signal generator for generating a third electric signal corresponding to an intensity of the first luminous flux passed through the second light incident port, and a fourth electric signal corresponding to an intensity of the second luminous flux passed through the second light incident port; and (g) a calculator for calculating a bilirubin concentration based on the first to fourth electric signals se that includes a processor that cancels the influence of skin by using the luminous fluxes of the different optical path length.