Abstract:
A method for utilizing polarization as a scheme for fluorescence removal from UV Raman spectra collected in a standoff detection scheme has been invented. In this scheme, a linearly polarized ultraviolet (UV) laser interacts with a material on a surface or in a container. The material generates Raman scattering with polarization contributions relative to that of the laser. The material possibly fluoresces as well, but the fluorescence is generally unpolarized. By subtracting a scaled version of the perpendicular component from the parallel component of the returned signal both relative to the laser source polarization—it is possible to generate a spectrum that is fluorescence free and contains the strongest features of the Raman scattered light.
Abstract:
In order to solve a problem that a local optical characteristic-changed region inside an object cannot be accurately estimated, an object observing apparatus includes: a light intensity information acquiring unit that acquires light intensity information received by each light-receiving probe; a light intensity change information acquiring unit that acquires, for each probe set, light intensity change information, from reference light intensity information and light intensity information; an estimating unit that acquires three-dimensional optical characteristic-changed region information, using the light intensity change information; and an output unit that outputs the optical characteristic-changed region information; the estimating unit including a correcting part that performs correction according to sensitivity attenuation in accordance with a depth; and a sparseness applying part that introduces sparseness for improving a space resolution, thereby acquiring the optical characteristic-changed region information. Accordingly, it is possible to accurately estimate a local optical characteristic-changed region inside an object.
Abstract:
A method and system for correcting the effect of intensity fluctuations of the transmitted light in an absorption spectroscopy system used for the detection or measurement of chemical species in a medium, whereby one or more modulation bursts are imposed onto a light beam that passes through the medium. This burst signal may be obtained by modulating the bias current of a tunable diode laser, and the modulation burst signal may be optimally at the second harmonic of the modulation frequency of a wavelength modulated beam to allow usage of the same signal path processing used for the spectroscopic detection of the measurand for a second harmonic detection system. The burst signal can be controlled using a smooth window function to minimise the effects of non-linear perturbations that are inherent in tunable diode laser wavelength modulation spectroscopy systems, of optical interference fringes (etalons) and of the residual light absorption by background chemical species or the measurand at the wavelength coinciding with the modulation burst.
Abstract:
Methods and apparatus are provided for determining weight percent of solids in a suspension using Raman spectroscopy. The methods can be utilized to acquire Raman spectral data from the suspension and to determine weight percent of solids in a process being carried out, for example, in a vessel, without the need to remove samples for analysis. The weight percent of the solids can be determined with a desired accuracy in a relatively short time, typically 10 minutes or less. The acquired Raman spectral data may be processed by chemometric software using, for example, a Partial Least Squares algorithm and data pretreatment to provide a predicted value of weight percent solids. In some embodiments, the invention is used to determine the weight percent of microparticles of a diketopiperazine in an aqueous solution.
Abstract:
An image processing apparatus includes: an interface unit configured to input an image signal from an imaging apparatus that exposes a specimen dyed with a fluorescent dye to excitation light and images fluorescence by a color imaging element; and a color correction circuit configured to retain information on a percentage of each of a component of a second color and a component of a third color with respect to a component of a first color corresponding to the excitation light in the image signal, which is determined in advance based on color filter spectral characteristics of the color imaging element, and reduce each of an amount corresponding to the percentage of the component of the second color and an amount corresponding to the percentage of the component of the third color from the input image signal.
Abstract:
Methods and apparatus are provided for determining weight percent of solids in a suspension using Raman spectroscopy. The methods can be utilized to acquire Raman spectral data from the suspension and to determine weight percent of solids in a process being carried out, for example, in a vessel, without the need to remove samples for analysis. The weight percent of the solids can be determined with a desired accuracy in a relatively short time, typically 10 minutes or less. The acquired Raman spectral data may be processed by chemometric software using, for example, a Partial Least Squares algorithm and data pretreatment to provide a predicted value of weight percent solids. In some embodiments, the invention is used to determine the weight percent of microparticles of a diketopiperazine in an aqueous solution.
Abstract:
The invention relates to an actuation and evaluation circuit for a laser diode (1) and a photodiode (3) for determining the concentration of a gas. The laser diode can generate light in the range of an absorption line of the gas. The circuit comprises a driver (10, 11, 12, 13) for generating a driving signal (17) for the laser diode (1), an assembly (8, 9) for generating a reference signal (20), and a subtractor (5) for subtracting the reference signal (20) from the signal (21) supplied by the photodiode. The invention further relates to a measuring device for determining the concentration of a gas by means of such an actuation and evaluation circuit. Finally, the invention relates to a corresponding method.
Abstract:
This disclosure relates generally to a sampling device, and more particularly, a sampling device that facilitates spectroscopic measurements with a variable path length and the necessary software controlled algorithms and methods for such a device.
Abstract:
This disclosure relates generally to a sampling device, and, more particularly, a sampling device that facilitates spectroscopic measurements with a variable path length and the necessary software controlled algorithms, and methods for using such a device.
Abstract:
The present invention reagents and methods for setting up an instruments having a multiplicity of detector channels for analyzing a multiplicity of fluorescent dyes. The present invention is particularly applicable in the field of flow cytometry.