Methods use a tunable notch filter for constructing a spectral map of electromagnetic radiation in a selected spectral band that is incident on a notch filter for a plurality of time periods. Electromagnetic radiation is passed by an electronically tuned notch filter to a detector array for the plurality of selected time periods, and the detector response is determined. For at least a first selected time period the notch filter is tuned to selectively attenuate the passing of one or more selected sub-bands of electromagnetic radiation in the selected spectral band. Information about the selectively attenuated radiation is determined and used along with information about the radiation passed to the detector array for each time period to construct a spectral map. Electronically tunable notch filters may be made with metamaterials such as patterned graphene.

A hazardous gas detector that includes a housing defining an interior region is provided. Also included is a laser emitting component oriented to emit a laser light away from the housing. Further included is a lens disposed within an aperture defined by the housing, the lens allowing returning infrared light of the laser light to enter the interior region. Yet further included is a mirror disposed within the interior region and oriented to split the returning laser light into a short wave infrared light and a long wave infrared light. Also included is a one-dimensional (1D) camera pixel array disposed within the interior region, the 1D camera imaging a planar region that includes an illuminated portion comprising the short wave infrared light.

A device for determining the composition of a mixture of fluids that flow along a pipe includes: a radiation source for illuminating the mixture with radiation; a detector for detecting radiation that has been attenuated by the mixture; and a device for monitoring the flow rate of fluid along the pipe and outputting a signal indicative of the flow rate. The device for determining further includes a device for adjusting the intensity of radiation emitting by the radiation source in response to the signal indicative of the flow rate so that the intensity of the radiation source is reduced if the flow rate reduces.

The present invention discloses a wavelength-modulable spectrum generator as well as a system and method for measuring concentration of a gas component based thereon. The wavelength-modulable spectrum generator includes a filter plate, a to-be-measured gas box and a light intensity receiving plate. A plate surface of the filter plate is encircled with N filter holes, and a filter lens with a specific refractive index is correspondingly fixedly arranged in each filter hole. A light source mounting position is fixed to a side of an in-light surface of the filter plate. After any light source is mounted at the light source mounting position, lights of the light source irradiate the filter lens. A rotation and deflection driving mechanism is connected with an out-light surface of the filter plate and drives the filter plate to rotate or deflect along the axis according to a preset angle.

A Raman spectroscopy system is provided. The spectroscopy system includes an optical switch including a first side having a pump inlet and a return outlet, and a second side having a plurality of pump outlets and a plurality of return inlets. The spectroscopy system includes at least one radiation source optically coupled to the pump inlet and a detector optically coupled to the return outlet. The spectroscopy system further includes a pump filter module optically coupled between the at least one radiation source and the pump outlets and a return filter module optically coupled between the detector and the return inlets. The spectroscopy system further includes a plurality of probes, each probe optically connected to at least one of the plurality of pump outlets by at least one excitation fiber and optically coupled to one of the return inlets by at least one emission fiber.

A method of performing Raman spectroscopy can include guiding a Raman pump beam with an optical fiber, where the Raman pump beam inducing fluorescence in the optical fiber. The beam and the fluorescence are coupled to a photonic integrated circuit (PIC) via the fiber. The beam is used to excite a sample in optical communication with the PIC via evanescent coupling and induces Raman scattering in the sample. The Raman scattering is collected via the PIC, and the Raman pump beam as well as the fluorescence is filtered out from the Raman scattering via the PIC.

A system and method for imaging a sample using Raman spectrometry. Optical fibers having opposite first ends and second ends are arranged with the first ends and second ends in respective two-dimensional arrays. The two-dimensional arrays maintain relative positions of the optical fibers to one another from the first ends to the second ends in a way that the first end of each optical fibers of the bundle can simultaneously collect a corresponding Raman signal portion scattered from specific spatial coordinates of the area of the sample. The so-collected Raman signal portions are propagated towards the corresponding second end, from which are outputted and detected simultaneously using an array of detectors.

A device for determining the composition of a mixture of fluids that flow along a pipe includes: a radiation source for illuminating the mixture with radiation; a detector for detecting radiation that has been attenuated by the mixture; and a device for monitoring the flow rate of fluid along the pipe and outputting a signal indicative of the flow rate. The device for determining further includes a device for adjusting the intensity of radiation emitting by the radiation source in response to the signal indicative of the flow rate so that the intensity of the radiation source is reduced if the flow rate reduces.

A spectrometer, such as a Raman spectrometer, adapted for analyzing a complex sample is provided. In an example implementation, the spectrometer may be able to determine one or more spectral characteristics of an inner subsurface layer or region of a complex sample (e.g., contents of a container). In one embodiment, for example, A spectrometer includes an excitation source configured to provide an excitation signal; an optical system configured to direct the excitation signal toward a sample and receive a spectroscopy signal from the sample. The optical system may include a spatial filter configured to separate or isolate at least one first portion of the spectroscopy signal from at least one second portion of the spectroscopy signal and pass the at least one first portion of the spectroscopy signal. A detector is configured to determine at least one spectral feature of the at least one first portion of the spectroscopy signal.

Systems and methods for thermal radiation detection utilizing a thermal radiation detection system are provided. The thermal radiation detection system includes one or more mercury-cadmium-telluride (HgCdTe)-based photodiode infrared detectors or Indium Arsenide (InAr)-based photodiode infrared detectors and a temperature sensing circuit. The temperature sensing circuit is configured to generate signals correlated to the temperatures of one or more of the plurality of infrared sensor elements. The thermal radiation detection system also includes a signal processing circuit.