Research Article Open Access

Detection of a One-Way Mirror Transmittance Byline Spectrometry

Abstract

The paper describes a system for light spectrum detection of an one-way mirror transmittance by line spectrometry. The system is composed of a focusing lens, a dispersion device and a monochromaticcamera. The focusing lens system determines the Region Of Interest (ROI), consistingof a slight rectangular area that can be considered as a linear array of adjacent cells,and sent the light emitted by the region to the entrance slit of the dispersion device. The light rays emerging from the dispersion device hit the area sensor of the camera,that produces an image composed by the spectra of the elementary cells of the ROI. The paper reports a processing procedure for transforming raw data produced bythe camera into transmittance or reflectance data. The system allows to measurespectra in the range 380-780nm, with spectral resolution of about 5nm.The spatialresolution, that is the dimension of the cells of the ROI, can be set by the imaginglens. The paper describes also an application realized to determine the spectraltransmittance of transparent or semi-reflective mirrors and plates.

M. Righi, M. Martinelli, A. Benassi, M. Chimenti, O. Salvetti.