Wavelength calibration model for prism-type echelle spectrometer by reversely solving prism’s refractive index in real time

• DOI: 10.1364/ao.55.004153
• Publication Date: 2016-05-13T20:44:50Z
• Authors: Rui Zhang; Bayanheshig; Lu Yin; Xiaotian Li; Jicheng Cui; Jin Yang; Ci Sun
• Keywords: Prism

In an echelle spectrometer equipped with a prism cross-dispersion element, wavelength calibration is very difficult because of the complex, nonlinear interaction between and grating. From geometry dispersion equations for grating, detailed mathematical model derived that fits refractive index in real time. An expression relating index, wavelength, image coordinates constructed, standard sources positions are adopted to timely calculate which affected by ambient factors such as temperature air pressure. Experimental results indicate fitting accuracy time approaches 10−4, while 10−3 nm entire spectral range.