Development of A Diffraction Spectrometer and its Control Program Using Commercial, Low-Cost Elements

Abstract

A diffraction spectrometer was developed, based on low cost commercial elements. The spectrometer was designed with the configuration of a transmission diffraction grating spectrometer with adjustable entrance slit. It was built with com-mercial elements like a holographic grating, collimator lens and a digital projector lens. For detection, a webcam CMOS sensor was used. A MATLAB based program was developed for the equipment, allowing the acquisition and processing of spectra. The optical defects were corrected using a non linear wavelength calibration. The SNR of final spectrum was increased in 14 times by processing the data. The Spectrometer showed an effective resolution of 1.4 nm and a precision of ±0.28nm in final tests, showing to work properly with a cost 10 times lower (in materials) to the commercial price of a similar equipment (Ocean Optics USB4000).