GAS SENSOR BASED ON THE SPECTRAL SPR EFFECT WITH COLORIMETRIC REGISTRATION OF RESPONSES

Abstract

A new variant of the optoelectronic sensor for the detection of gas molecules based on the effect of spectral surface plasmon resonance (SPR) in the chromatic mode with colorimetric registration of the color components of the reflected light is proposed. As an optical sensitive element, a thin silver film was used on the base face of the prism in the Kretschmann geometry, which made it possible to realize a full-fledged SPR effect in the entire visible spectral range from 450 to 700 nm. To measure the optical response, the method of video registration of R, G, B components of reflected light by color webcam was used. The optical scheme of the set-up allowed to simultaneously obtain the full spectrum of plasmon-reflected light without the use of rotating mechanical parts. The sensory effect was a change in the refractive index of the surrounding medium under the action of gases, which directly affected the parameters of the spectral SPR. A laboratory prototype of an optoelectronic sensor device was created, and the effectiveness of the proposed method was evaluated by detection of a number of organic analytes vapors .