Method of optically measuring liquid in porous material

摘要

In a method of measuring optical characteristics of a component in a liquid impregnated in a porous material with no affection by the porous material, a light beam having an absorbable wavelength which is absorbed by the component in the liquid and a light beam having a wavelength which is longer than the absorbable wavelength are projected to the porous material, and a quantity of light having the wavelength which is absorbed by the component in the liquid is compensated by a quantity of transmitted light having the wavelength longer than the absorbable wavelength.