Simultaneous Measurement of Optical Rotation Angle and Transmittance by Curve Fitting Based on Optical Null Methods
B-Y. Liu and H-Z. Jia
We present a curve fitting approach for calculating both transmittance and optical rotation angles via the measurement system based on optical null methods. The system contains a digital signal processor (DSP) controlled step-motor rotating stage structure and a modulated laser diode (LD). Ink and sugar solutions of different concentrations are tested. Results for dual parameter measurement have been discussed. The feasibility, accuracy, along with the wide measuring range of this fitting approach is verified.
Keywords: Laser diode (LD), optical rotation angle, transmittance, optical null method, curve fitting, sugar solution, ink solution