RobustATR: Substrate-Integrated Hollow Waveguide Coupled Infrared Attenuated Total Reflectance Sensors

Abstract

Small and compact mid-infrared devices are of increasing importance, as there are several applications demanding on-site and real-time measurements in harsh real-world scenarios. The RobustATR, an innovative infrared attenuated total reflectance (IR-ATR) accessory, has been developed and tested with exemplary analytes integrating a single-wavelength Fabry–Pérot quantum cascade laser as light source for testing the feasibility of a potentially miniaturized overall sensor design. Successful direct coupling of the laser radiation via substrate-integrated hollow waveguide (iHWG) coupling elements to the sensor interface could be shown, whereby exemplary analytes of environmental and medical relevance were tested, revealing the future potential for real-world applications.

Keywords

• infrared attenuated total reflection
• IR-ATR
• quantum cascade laser
• QCL
• substrate-integrated hollow waveguide
• iHWG