Light Absorption Measurement of Solid Particles by Absorption Analyzer using Multi-Wavelength Optical Method

In order to monitor the particulates by optical sensor, the amount of absorbed light by particles should be measured simply and cheaply. In this research, an automated, nondestructive system is designed and fabricated using multi-wavelength method that can measure absorption spectrum of solid particles. Calibration of proposed system was also carried out by reference spectrometer and the correction coefficients were obtained. Due to scarcity of data in resulted spectrograph, Hermit interpolation was applied to improve graph resolution. Moreover, instead of utilizing different light sources with different spectrum which is currently common in this field, a wide range of light source was used with various optical filters. The proposed system can measure absorption spectrum of materials in the range of  with the accuracy of 1 nm. The absorption spectrum of three different samples were measured that the results show the similarity with the reference system. Comparing this high accurate optical sensing method with other similar methods reveals that the proposed system is cost-effective and can be utilized as a portable absorption analyzer.