Measurement of the optical properties in agricultural products by using steady spatially resolved spectroscopy and applications

Based on research using theory of light transportation in biological tissues, especially for the agricultural products with the feature of strong scattering, the light transport equation was solved by diffusion approximation theory. According to the solution of diffusion approximation, a nondestructive method to measure the optical properties of agricultural products was investigated based on establishing steady spatially resolved spectroscopy, and a device which can determine the optical properties of agricultural products was designed. Intralipid-10% and Evans blue were used as standard phantoms to verify the system at 750 nm wavelength. The system was stable and reliable from the calibration of the system and the result was consistent with other researchers’ reports. Furthermore, the apple and tomato samples were measured to obtain the optical properties, the corresponding values of the optical properties for reduced scattering coefficient , absorption coefficient μa measured on apple samples were (0.97711±0.191858) mm-1 and (0.00321±0.00076) mm-1; the reduced scattering coefficient and absorption coefficient of tomato samples were (1.1345±0.22749) mm-1 and (0.00140±0.00045) mm-1, respectively. The advantage of steady spatially resolved spectroscopy for practical use in measuring fruit and vegetable samples is prior to time spatially resolved spectroscopy TRS method.