Experimental study and modelization of oblique incidence effect on QWIP's spectral response

Autor: Philippe F. Bois, Isabelle Ribet-Mohamed, Sabine Suffis-Carretero, Eric Costard, Alfredo De Rossi, Nicolas Guérineau, Michel Tauvy
Rok vydání: 2004
Předmět:
Zdroj: SPIE Proceedings.
ISSN: 0277-786X
Popis: As far as calibrated radiometric imaging is concerned, a complete prediction of oblique incidence effect on the FPA pixels’ response is required. Since a light coupling scheme needs to be used in QWIP detectors, this effect is particularly complicated to understand. This article presents two complementary test benches which allow to quantify the effect of oblique incidence on cooled infrared detectors issued from different technologies. The first test bench performs measurements over a wide angular range with low background emission levels, but gives spectrally integrated measurements. The second one delivers spectrally resolved responses for incident angles lower than 30°. In order to validate both experimental concepts, we studied QWIPs equipped with 2D periodic gratings. Relatively large pixels (100x100μm 2 ) were chosen to ease comparison with models. Calculations based on the modal expansion method reveal that diffraction off an infinite grating does not account very well for the observed spectral responses.
Databáze: OpenAIRE