Method based on optical rotatory dispersion for determining wavelength

A method based on optical rotatory dispersion is proposed for determining wavelength. The optical rotation angle with a certain wavelength is measured by the displacement between two light intensity curve with or without quart in specimen holder. Through optical rotatory dispersion equation, the wavelength can be calculated when the specific rotation is known. After multiple experiments, the absolute error is about ±0.17 nm ranging from 400 nm to 700 nm with the relative error of ±3 × 10−4 and the stand deviation of 30 sets of measurements is achieved to 0.11 nm, which verifies the feasibility of proposed method and stability of whole measurement setup with simple light path and structure.