Spectroscopic method and apparatus for measuring sugar concentrations

A spectrophotometric apparatus for measuring concentrations of sugars in samples, which comprises

• an interferometer for emitting superposed light beams,
• a controller for adjusting light intensity of a light source which is placed in said interferometer,
• an integrating sphere for collecting diffusely reflected light beams from a sample placed at said integrating sphere,
• a photo detector for detecting said collected light and converting it into an electric signal,
• a processing means for processing electric signal from said photo detector so as to compute absorption spectrum of the sugar in said sample to be determined and for determining the concentration of the sugar under measurement on the basis of said absorption spectrum, and
• a means for selecting optimum wavelengths for a use for said absorption spectrum from a wavelength band of from 950 to 1,150 nm, from 1,150 to 1,300 nm, or from 1,300 to 1,450 nm,
• said processing means including a means whereby, on the basis of the difference between the absorption spectrum of the sugar under measurement at a first depth in said sample which is computed for light intensity of said light source in said interferometer set at a first prescribed value and absorption spectrum of said sugar at a second depth which is computed for light intensity of said source set at a second prescribed value, the absorption spectrum of the sugar under measurement at a deeper region between said first and second depths in said sample is computed and including furthermore a means whereby, on the basis of said absorption spectrum at said deeper region, the concentration of the sugar under measurement in said deeper region in the sample is computed.