Abstract:
This relates to systems (600) and methods for measuring a concentration and type of substance in a sample (620) at a sampling interface. The systems (600) includes a light source (602), one or more optics (606, 610, 612), one or more modulators (634, 636), a reference (608), a detector (630), and a controller (640). The systems and methods disclosed can be capable of accounting for drift originating from the light source, one or more optics, and the detector by sharing one or more components between different measurement light paths. Additionally, the systems can be capable of differentiating between different types of drift and eliminating erroneous measurements due to stray light with the placement of one or more modulators between the light source and the sample or reference. Furthermore, the systems can be capable of detecting the substance along various locations and depths within the sample by mapping a detector pixel and a microoptics to the location and depth in the sample.
Abstract:
Frequency registration deviations occurring during a scan of a frequency or wavelength range by a spectroscopic analysis system can be corrected using passive and/or active approaches. A passive approach can include determining and applying mathematical conversions to a recorded field spectrum. An active approach can include modifying one or more operating parameters of the spectroscopic analysis system to reduce frequency registration deviation.
Abstract:
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.
Abstract:
A multi-channel double-pass imaging spectrometer based on a reimaging or relayed all-reflective optical form, such as a four-mirror anastigmat (4MA) or five-mirror anastigmat (5MA). In one example, such a spectrometer includes a slit through which incident electromagnetic radiation enters the spectrometer, an imaging detector positioned at an image plane of the spectrometer co-located with the slit, and double-pass all-reflective reimaging optics configured to receive the electromagnetic radiation from the slit and to output a collimated beam of the electromagnetic radiation, and further configured to produce a reimaged pupil positioned between the double-pass all-reflective reimaging optics and the image plane. The spectrometer further includes at least one dispersive element configured to spectrally disperse the infrared electromagnetic radiation in each channel and being oriented to direct the dispersed output through the double-pass all-reflective reimaging optics to the image plane.
Abstract:
The present invention concerns an optical measurement system (1) comprising an electrically tunable Peltier element(11), a detector (23) for detecting radiation from a radiation source (25) in a measurement area(26), the detector (23) being in thermal connection with the Peltier element(11), an electrically tunable Fabry-Perot interferometer (10) placed in the path of the radiation (16) prior to the detector(23), the Fabry-Perot interferometer (10) being in thermal connection with the Peltier element (11), and control electronics circuitry configured to control the Peltier element(11), the interferometer(10), and the detector(23). The present invention further concerns a method for analyzing the spectrum of an object.
Abstract:
The present disclosure provides methods and apparatus for testing light-emitting diodes (LEDs), for example, measuring the optical radiation of an LED. In a method, a pulse-width modulated signal is provided to the LED. One or more characteristics of the PWM signal are varied so as to provide a forward voltage, V f , corresponding to a target junction temperature, T j , of the LED. The optical radiation of the LED is measured when the LED obtains the target junction temperature.
Abstract:
A spectrometer configurable for field analyses of chemical properties of a material is provided. The spectrometer includes: at least one sensor adapted for providing Fourier transform infrared spectroscopy (FTIR) surveillance and at least another sensor for providing Raman spectroscopy surveillance. The spectrometer can be provided with a user accessible instruction set for modifying a sampling configuration of the spectrometer. A method of determining the most likely composition of a sample by at least two technologies using the spectrometer is also provided.
Abstract:
An apparatus is configured to measure various properties of sample in a sample chamber such as, for example, water activity. The apparatus includes a tunable diode laser that emits laser radiation into the sealed chamber without passing through the air outside the sample chamber or a wall of the sample chamber. The laser radiation only passes through the gaseous mixture in the sample chamber. A temperature sensor such as an infrared thermometer is positioned to measure the temperature of a sample in the sample chamber. The apparatus may be configured to include a plurality of sample containers each of which includes a sealed sample chamber. The sample containers may be automatically fed through the apparatus and analyzed with the tunable diode laser without any operator input or interaction.