A gas analysis system with an FTIR spectrometer preferably utilizes a long path gas cell, a narrow band detector, and an optical filter that narrows the detection region. The interferograms are further prevent baseline drift and analyze the resultant spectra.

Systems and methods are disclosed to determine the concentration of a species within a sample. An example method may include collecting optical loss data over a range of frequencies from the sample using a spectroscopy system; placing the optical loss data into a plurality of bins, each bin having a defined frequency width; determining an average optical loss data value for the optical loss values within each bin that have an optical loss value less than a threshold value; removing the optical loss data within each bin having a value outside a tolerance range bounding the average optical loss data value for the respective bin; fitting a spectral curve to the remaining optical loss data; and determining the concentration of the species within the sample based on the spectral curve.

Various embodiments disclosed herein describe an infrared (IR) imaging system for detecting a gas. The imaging system can include an optical filter that selectively passes light having a wavelength in a range of 1585 nm to 1595 nm while attenuating light at wavelengths above 1600 nm and below 1580 nm. The system can include an optical detector array sensitive to light having a wavelength of 1590 that is positioned rear of the optical filter.

Various embodiments disclosed herein describe an infrared (IR) imaging system for detecting a gas. The imaging system can include an optical filter that selectively passes light having a wavelength in a range of 1585 nm to 1595 nm while attenuating light at wavelengths above 1600 nm and below 1580 nm. The system can include an optical detector array sensitive to light having a wavelength of 1590 that is positioned rear of the optical filter.

A method of processing an analog signal includes receiving, into signal processing circuitry from compensation circuitry, an offset compensation signal, the offset compensation signal having (i) a polarity opposite a polarity of a gain error of the signal processing circuitry and (ii) a magnitude equal to a nominal compensation value plus a deviation. The method includes generating, by the signal processing circuitry, an output signal based on an analog signal received into the signal processing circuitry, including applying the offset compensation signal to an intermediate signal generated by the signal processing circuitry. The method includes scaling the output signal based on the deviation between the magnitude of the offset compensation signal and the nominal compensation value.

Embodiments are disclosed for terahertz spectroscopy and imaging in dynamic environments. In an embodiment, a method comprises emitting a continuous electromagnetic (EM) wave in a terahertz (THz) frequency band into a dynamic environment. The EM THz wave is reflected off an object in the environment. A spectral response of a received signal indicative of the reflected EM wave is determined that includes absorption spectra at a frequency in the THz frequency band. The absorption spectra is indicative of a transmission medium in the environment. The spectral response of the received signal is compensated for fixed and frequency-specific losses. The compensated absorption spectra is compared with known absorption spectra of target transmission mediums. Based on results of the comparing, a particular target transmission medium is identified as being the transmission medium in the environment. The absorption spectra loss is used to determine a concentration level of the target transmission medium.

An information processing method includes the steps of calculating information on object illumination light for illuminating an object based on spatial distribution information of illumination light and orientation information of the object, and correcting information on the reflected light so as to reduce influence of the object illumination light based on the information on the object illumination light and information on the reflected light from the object.

A spectrometer device includes a Fabry-Perot interferometer unit, which comprises a first carrier substrate, wherein the first carrier substrate is arranged on a lower side of the Fabry-Perot interferometer unit and includes an optical aperture. The spectrometer includes at least one of a first substrate, which is arranged on an upper side of the Fabry-Perot interferometer unit, which faces away from the lower side, and a second substrate with the first carrier substrate arranged with the lower side on the second substrate. The spectrometer further includes a photodetector device arranged on or in the at least one of the second substrate and the first substrate. A first electrical connection region of the photodetector device and a second electrical connection region of the Fabry-Perot interferometer unit are electrically contacted from the same direction.

An on-chip spectroscopic sensor includes a tunable diode laser. A laser driver for drives the tunable diode laser. An analyte test cavity receives a chemical sample and exposes the received chemical sample to light from the tunable diode laser. An optical detector detects light emerging from the analyte test cavity as a result of the laser exposure. A spectral analyzer determines a spectrum of the emerging light, matches and removes one or more known optical fringe patterns from the determined spectrum, and determines a composition or concentration of the chemical sample from the optical fringe pattern-removed spectrum.

Various embodiments disclosed herein describe an infrared (IR) imaging system for detecting a gas. The imaging system can include an optical filter that selectively passes light having a wavelength in a range of 1585 nm to 1595 nm while attenuating light at wavelengths above 1600 nm and below 1580 nm. The system can include an optical detector array sensitive to light having a wavelength of 1590 that is positioned rear of the optical filter.