Instrument for Chemical Analysis of Liquid Samples based on a CMOS Compatible Non-Specific NDIR Microarray

摘要

A generic purpose, compact and affordable instrument for the chemical analysis of liquid samples based on the non dispersive infrared (NDIR) scheme is presented. It comprises a detector module built from two matching arrays of CMOS compatible thermopiles and non-specific infrared filters (Fabry-Perot resonators). Each filter provides a set of transmission peaks distributed along the mid-infrared spectral range instead of a single transmission peak associated to a specific wavelength, so that each channel collects information concerning the absorption at several wavelengths, and the whole array produces a pattern with information regarding the sample absorption in the entire mid-infrared range. Strictly speaking, this instrument does not operate as a spectrometer (measuring the sample absorption as a function of wavelength), but it is an affordable alternative that makes available patterns with enclosed spectroscopic information.