Resumo

MARTINEZ PEREZ, L. et al. Application of the total internal reflection phenomenon as a gas sensing technique using evaporated SnO₂ thin films. Rev. mex. fis. [online]. 2004, vol.50, n.5, pp.518-521. ISSN 0035-001X.

In this work it is shown that the Total Internal Reflection (TIR) phenomenon can be exploited for gas detection. Total internal reflectance measurements for evaporated SnO₂ thin films on quartz substrates are measured at ambient conditions. Changes in the reflectance measurements are measured when CO₂ or N₂ gas flows on the surface of the SnO₂ films. The observed shift in the measured reflectance is defined as the signal of the sensor. Preliminary results show that the maximum response takes place at incident angles close to the critical angle of the quartz-air system.

Palavras-chave : Total Internal Reflection; Optical gas sensors; Tin dioxide thin films; anisotropic materials; CO₂ detection.