Abstract:
A multi-channel colorimeter has a spectral means which separates light to be measured into components of different wavelengths, a photoelectric converter provided with multiple wavelength channels that receive the separated light to be measured according to the wavelengths to output the corresponding signals at the respective wavelengths, a calculating section that calculates spectral characteristics of the light to be measured based on a composite spectral sensitivity which approximates a predetermined spectral sensitivity by integrating the outputs from the respective wavelength channels multiplied by predetermined weighting factors; and a special weighting factor generator that correctively sets the weighting factors as special weighting factors depending on a spectral intensity of the light to be measured.
Abstract:
An apparatus for optical sensing of samples includes an optical source, an optical assembly, a sample holder, an objective lens, and a detector. The objective lens collimates light emitted by the sample. Preferably, the optical assembly rotates about an axis, allowing the sensing apparatus to sense results from plural locations on a sample without moving the sample. Moving the sample in a linear direction while rotating the optical assembly allows sensing of an entire sample. Preferably, light from the optical source enters the optical assembly along the axis of rotation. Sensing methods consistent with the invention are also described.
Abstract:
A spectroscopy system is provided which is optimized for operation in the VUV region and capable of performing well in the DUV-NIR region. Additionally, the system incorporates an optical module which presents selectable sources and detectors optimized for use in the VUV and DUV-NIR. As well, the optical module provides common delivery and collection optics to enable measurements in both spectral regions to be collected using similar spot properties. The module also provides a means of quickly referencing measured data so as to ensure that highly repeatable results are achieved. The module further provides a controlled environment between the VUV source, sample chamber and VUV detector which acts to limit in a repeatable manner the absorption of VUV photons. The use of broad band data sets which encompass VUV wavelengths, in addition to the DUV-NIR wavelengths enables a greater variety of materials to be meaningfully characterized. Array based detection instrumentation may be exploited to permit the simultaneous collection of larger wavelength regions.
Abstract:
The present invention is a dispersive, diffraction grating, NIR spectrometer that automatically calibrates the wavelength scale of the instrument without the need for external wavelength calibration materials. The invention results from the novel combination of: 1) a low power He—Ne laser at right angles to the source beam of the spectrometer; 2) a folding mirror to redirect the collimated laser beam so that it is parallel to the source beam; 3) the tendency of diffraction gratings to produce overlapping spectra of higher orders; 4) a “polka dot” beam splitter to redirect the majority of the laser beam toward the reference detector; 5) PbS detectors and 6) a software routine written in Lab VIEW that automatically corrects the wavelength scale of the instrument from the positions of the 632.8 nm laser line in the spectrum.
Abstract:
Systems and methods for applying different color calibrations at different locations in an imaging photometer measurement are disclosed herein. In one embodiment, a method for measuring a light source having a first area with a first spectral distribution and a second area having a second spectral power distribution can include selecting one or more data points in the first area for measurement. The method then includes applying a calibration to the selected data points in the first area such that a desired colorimetric result is displayed for each data point in a single colorimetric measurement of the first area. In several embodiments, the method can further include selecting one or more data points in the second area, and applying a different calibration to the selected portions of the second area such that a desired colorimetric result is also displayed for each data point in the second area.
Abstract:
The invention relates to a spectrometer arrangement (10) comprising a spectrometer (14) for producing a spectrum of a first wavelength range of radiation from a radiation source on a detector (42). Said arrangement also comprises: an Echelle grating (36) for the spectral decomposition of the radiation penetrating the spectrometer arrangement (10) in a main dispersion direction (46); a dispersing element (34) for separating the degrees by means of spectral decomposition of the radiation in a transversal dispersion direction (48) which forms an angle with the main dispersion direction of the Echelle grating (36), in such a way that a two-dimensional spectrum (50) can be produced with a plurality of separated degrees (52); an imaging optical element (24, 38) for imaging the radiation penetrating through an inlet gap (20) into the spectrometer arrangement (10), in an image plane (40); and a surface detector (42) comprising a two dimensional arrangement of a plurality of detector elements in the image plane (40). The inventive arrangement is characterised in that another spectrometer (12) comprising at least one other dispersing element (64) and another imaging optical element (60,66) is provided in order to produce a spectrum (68) of a second wavelength range of radiation, which is different from the first wavelength range, from a radiation source on the same detector (42). The spectra can be spatially or temporally separated on the detector.
Abstract:
The present disclosure provides for a device, as well as a system and method associated therewith, for, among other things, providing: (i) up to five distinct measurement angles along with an illumination reference channel; (ii) a plurality of illumination sources that provide a focused beam of illumination at specific desired angles of incidence to a sample under target; (iii) a shutter mechanism incorporating a calibration transfer standard; (iv) an internal optical system that is operatively associated with a gimbaled structure suitable to allow vertical and angular conformity to a target sample; and (v) a handheld and operated enclosure incorporating a user interface with a visual display unit complete with interactive navigation means and an activation switch, and a number of surface detecting contact elements operatively associated with the optical system and shutter mechanism.
Abstract:
A downhole fluid analysis system comprises an input light signal that is directed through a fluid sample housed in a sample cell. The input light signal may originate from a plurality of light sources. A light signal output from the sample cell is then routed to two or more spectrometers for measurement of the represented wavelengths in the output light signal. The output of the spectrometers is then compared to known values for hydrocarbons typically encountered downhole. This provides insight into the composition of the sample fluid. Additionally, the input light can be routed directly to the two or more spectrometers to be used in calibration of the system in the high temperature and noise environment downhole.
Abstract:
This lighting device comprises a plurality of wavelength range extraction unit for extracting light in different wavelength ranges from light of a light source, a shutter unit for shutting each piece of light extracted by each of the wavelength range extraction units, a selector unit for selecting light to be shut by the shutter unit, and a combiner unit for combining a plurality of pieces of light that is not shut by the shutter unit.
Abstract:
Weak signals scattered from analytes at multiple wavelengths can be summed to illuminate either a single detector or a multiplicity of detectors, offering the possibility of concentrating the spectral energy on a smaller total detector area. In addition, a method is disclosed whereby a calibration of the resulting signal for a given analyte can be obtained by means of measuring the quantity of water in the sample volume and by means of measuring the salinity of the fluid in the sample volume.