Abstract:
An optical head for receiving incident light is provided. The optical head comprises a transmissive cosine corrector and a reflector disposed to face the transmissive cosine corrector. The transmissive cosine corrector is disposed in an optical path of the incident light and shields the reflector from the incident light. The transmissive cosine corrector converts the incident light to scattered light having a Lambertian pattern. The reflector has an optical output section that transmits the scattered light and a reflective section that reflects the scattered light to the transmissive cosine corrector and/or the other portions of the reflective sections. An optical system using the optical head is also provided.
Abstract:
A method for deriving a background-corrected portion of a measured optical emission spectrum comprising the steps of identifying two or more background correction points from the portion of the measured emission spectrum; deriving a background correction function fitted to the identified background correction points, and applying the background correction function to the portion of the measured emission spectrum so as to produce a background-corrected portion of the emission spectrum, wherein the background correction points are identified from the measured data points by consideration of the gradients between the measured data points.
Abstract:
The invention relates to a polyamide comprising at least one repeat unit corresponding to the general formulation: X·Y in which: X represents a cycloaliphatic diamine and Y represents an aliphatic dicarboxylic acid chosen from dodecanedioic (C12) acid, tetradecanedioic (C14) acid and hexadecanedioic (C16) acid, characterized in that said dicarboxylic acid comprises organic carbon of renewable origin, determined according to Standard ASTM D6866. The invention also relates to a composition comprising this polyamide and also to the use of this polyamide and of such a composition.
Abstract:
Various embodiments disclosed herein describe a divided-aperture infrared spectral imaging (DAISI) system that is adapted to acquire multiple IR images of a scene with a single-shot (also referred to as a snapshot). The plurality of acquired images having different wavelength compositions that are obtained generally simultaneously. The system includes at least two optical channels that are spatially and spectrally different from one another. Each of the at least two optical channels are configured to transfer IR radiation incident on the optical system towards an optical FPA unit comprising at least two detector arrays disposed in the focal plane of two corresponding focusing lenses. The system further comprises at least one temperature reference source or surface that is used to dynamically calibrate the two detector arrays and compensate for a temperature difference between the two detector arrays.
Abstract:
A method and apparatus for obtaining reference samples during the generation of a mid-infrared (MW) image without requiring that the sample being imaged be removed is disclosed. A tunable MIR laser generates a light beam that is focused onto a specimen on a specimen stage that moves the specimen in a first direction. An optical assembly includes a scanning assembly having a focusing lens and a mirror that moves in a second direction, different from the first direction, relative to the stage such that the focusing lens maintains a fixed distance between the focusing lens and the specimen stage. A light detector measures an intensity of light leaving the point on the specimen. A controller forms an image from the measured intensity. A reference stage is positioned such that the mirror moves over the reference stage in response to a command so that the controller can also make a reference measurement.
Abstract:
A method and apparatus for testing materials for testing materials using infrared spectrometry. Calibration of an infrared spectrometer for use in testing materials including the steps of: selecting variables which have the potential to influence the physical characteristics of a composite used in the aerospace industry, selecting values for each variable and inputting the variable and values into a design of experiments model, thereby obtaining a sample test matrix.
Abstract:
This invention relates to a system and method to improve the signal to noise ratio (SNR) of optical spectrometers that are limited by nonrandom or fixed pattern noise. A signal from a sample is collected using a short test exposure, a total observation time to maximize SNR is calculated, and the total observation time is achieved by averaging multiple exposures whose time is selected based on the time dependent noise structure of the detector. Moreover, with a priori knowledge of the time dependent noise structure of the spectrometer, this method is easily automatable and can maximize SNR for a spectrum of an unknown compound without any user input.
Abstract:
A printer includes a printing section that ejects an ink, and a spectrometer that disperses incident light. The spectrometer includes a window section that transmits the light, an optical filter device, and a light receiving section. The optical filter device includes a variable wavelength interference filter as a dispersing element that disperses light transmitted by the window section. The light receiving section receives the light which is dispersed by the variable wavelength interference filter. A dirtiness of the window section is detected based on measured values corresponding to each of a plurality of wavelengths obtained by spectrally measuring light from a reference object, and reference values corresponding to each of the plurality of wavelengths.
Abstract:
A method for analyzing the condition of a spectrometer is provided. In one embodiment, the method includes acquiring optical data from a spectrometer of a downhole tool during flushing of a flowline and selecting a data set from the acquired optical data. The method can also include estimating light scattering and optical drift for the spectrometer based on the selected data set and determining impacts of the estimated light scattering and optical drift for the spectrometer on measurement accuracy of a characteristic of a downhole fluid determinable through analysis of the downhole fluid using the spectrometer. Additional methods, systems, and devices are also disclosed.
Abstract:
A polarization image sensor includes: photodiodes arranged on an image capturing plane; a color mosaic filter in which color filters in multiple different colors are arranged to face the photodiodes; an optical low-pass filter which covers the color mosaic filter; and polarization optical elements located closer to a light source than the optical low-pass filter is. Each polarization optical element covers an associated one of the photodiodes and makes light which is polarized in a predetermined direction in a plane that is parallel to the image capturing plane incident onto the optical low-pass filter. The color filters are arranged so that light that has passed through polarization optical elements is transmitted through an associated one of the color filters in a single color. Each color filter covers multiple photodiodes.