59 results about "Reflection spectroscopy" patented technology

A currency genuineness detection system using plurality of opto-electronic sensors with both transmission and reflective (including fluorescence) properties of security documents is developed. Both detection sensing strategies utilise integrated response of the wide optical band sensed under UV visible along with optional near infra red light illumination. A security document is examined under static condition. A window signal signature is thus possible from photodetectors responses for various kinds of documents of different denominations, kinds and country of origin. A programmable technique for checking the genuineness of a security document is possible by feeding a unique code of the currency under examination.

The invention relates to a method for detecting the nitrogen content in fresh tea leaves by a visible and near-infrared diffuse reflection spectrum technology, belonging to the technical field of agriculture and forestry life information detecting. The method comprises the steps: firstly, a portable radiation spectrometer is utilized to acquire diffuse reflection spectral information on the fresh tea leaves of a canopy in the range 350 to 2500nm; the nitrogen content in fresh tea leaves is accurately measured by a national standard method in a laboratory and the relative value of the nitrogen content in fresh tea leaves is measured fast by an SPAD and the like; then a calibration model of the nitrogen content in fresh tea leaves is established by a chemometrics method; and finally, the calibration model is used for detecting or evaluating the nitrogen content of fresh tea leaves to be detected. The method can detect the nitrogen content in fresh tea leaves quickly and accurately without damages, and conveniently estimate the nitrogen nutrition level of tea plants, thus providing parameter basis and guidance for the fertilizing management in tea garden field.

A thickness of a wafer during polishing operation is detected to accurately perform the polishing. A thickness measuring method, which measures the thickness of the wafer of wafer 7 in polishing a surface, comprises the steps of irradiating the thin film-like material during the surface polishing from a backside with probe light, measuring a reflectance spectrum with a dispersion type multi-channel spectroscope using a photodiode array which has particularly high sensitivity to light having a wavelength ranging from 1 to 2.4 μm, and calculating the thickness on the basis of a wave form of the reflectance spectrum. The surface polishing is performed while the thickness of the wafer 7 is measured by the above-described thickness measuring method, and the polishing is finished when the thickness of the wafer 7 reaches a target thickness.

A rapid, non-invasive breath-test method and device for diagnosing the presence or absence of H. pylori in a subject without administration of isotopic tracers is described. The device consists of a highly sensitive colorimetric ammonia sensor placed in contact with sampled subject breath. The sensor is measured using appropriate reflection spectroscopy instrumentation. The breath-test method consists of measuring a basal ammonia level with the device, administering non-isotopic urea and continuing measurement of the ammonia content in a plurality of consecutive breaths. Diagnostic differences in breath ammonia are identified between H. pylori infected and uninfected individuals.

A method to change the color of hair. The method includes measuring an initial reflectance spectrum of a sample of the hair and analyzing a contribution of a plurality of natural hair factors to the initial reflectance spectrum. The method also includes calculating a hair treatment based on another reflectance spectrum. A system to measure a reflectance spectrum of a sample includes an integrating sphere having a sampling port and an inner surface and a window disposed near the sampling port. The window is configured for being placed in close contact with the sample. The system also includes a light source configured to project light onto the sample via the window and a light detector configured to analyze light reflected from the inner surface to produce the reflectance spectrum of the sample.

A method to change the color of hair. The method includes measuring an initial reflectance spectrum of a sample of the hair and analyzing a contribution of a plurality of natural hair factors to the initial reflectance spectrum. The method also includes calculating a hair treatment based on another reflectance spectrum. A system to measure a reflectance spectrum of a sample includes an integrating sphere having a sampling port and an inner surface and a window disposed near to the sampling port. The window is configured for being placed in close contact with the sample. The system also includes a light source configured to project light onto the sample via the window and a light detector configured to analyze light reflected from the inner surface to produce the reflectance spectrum of the sample.

The invention relates to refractometry and attenuated reflectance spectrometry in a wellbore environment. Specifically, it pertains to a robust apparatus and method for measuring refractive index of fluids along a continuum (rather than in steps), and for measuring attenuated reflectance spectra, and for interpreting the measurements made with this apparatus to determine a variety of formation fluid parameters. The present invention provides a method and apparatus to distinguish between gas and liquid based on the much lower index of refraction of gas. It can also be used to monitor fluid sample clean up over time. The refractive index of a wellbore fluid is determined from the fraction, R, of light reflected off the interface between a transparent window that has a known refractive index and this fluid. Preferably, the refractive index is measured at some wavelength of light for which the fluid is not highly attenuating but is optimally attenuating. The adjacent transmission spectrometer can be used to correct the refractive index measurement for attenuation at those wavelengths, which it monitors. Also, this reflection-based refractometer design can be used as an attenuated reflectance spectrometer at highly attenuating wavelengths.

The invention discloses a diffuse reflection spectrum analyzer of ultraviolet, visible and near-infrared on-line detection, comprising a housing. A lighting system, a probe, an optical beam splitting system, a signal acquisition system, a correction system and a spectrum processing system are arranged in the housing, wherein the lighting system, the signal acquisition system, the correction system and the spectrum processing system are jointly connected with a power supply system. The lighting system is used for irradiating ray of ultraviolet, visible and near-infrared wave band to light a detected object; the probe is used for collecting the ray of the detected object after diffuse reflection and sends the collected ray to the optical beam splitting system; a grating is utilized to form light of different wavelengths by ray; the signal acquisition system converts the optical signal into a digital signal, and the digital signal is collected; and the spectrum corrected by the correction system is processed, analyzed and displayed by the spectrum processing system so as to determine a detection result. The invention has the advantages of wide application range and accurate measurement.

A currency genuineness detection system with visual discrimination complemented by automatic discrimination using plurality of opto-electronic sensors with reflective and fluorescence properties of security documents is developed. The detection sensing strategy utilizes integrated response of the wide optical band sensed under UV visible along with optional near infra red light illumination. A security document is examined under static condition. A window signalsignature is thus possible from the photodetectors responses for various kinds of documents of different denominations, kinds and country of origin. A programmable technique for checking the genuineness of a security document is possible by feeding a unique code of the currency under examination.

The invention discloses a fruit sugar degree sorting device and method based on weighing and sorting line transformation. The fruit sugar degree sorting device and method based on the weighing and sorting line transformation comprises a mechanical conveying device, a visible near-infrared spectrum detection device and a sorting control device. Fruits are conveyed into the visible near-infrared spectrum detection device by the mechanical conveying device, a vertical light beam is used for irradiating the fruits to be detected. The light beam on the fruits reflects through the diffuse reflectionoptical principle, the visible near-infrared spectrum detection device use a visible near-infrared diffuse reflection spectrum to carry out on-line detection and classification for the sugars and acidity in the fruits, the detected sugars and acidity are transmitted to the sorting control device, and the sorting is achieved by turning over a fruit tray. By collecting the visible near-infrared diffuse reflection spectrum of the fruits in the wave band range of 300nm-1100nm and using a prediction model of predicting the sugars and acidity of the fruits, the content of sugars and acidity in thefruits is calculated, and the on-line detection and automatic sorting of the sugars and acidity are achieved in cooperation with a automatic control system.

The invention discloses a tera-hertz photoelectric characteristic test system capable of realizing multiple test functions on photoelectric characteristics and the like of Fourier spectra, transmittance spectra, reflection spectra and tera-hertz electronic devices by combination of various customized light sources and detectors, light path components selected by a user, and addition of peripheral auxiliary equipment. The tera-hertz photoelectric characteristic test system has the advantages of high signal-to-noise ratio, high resolution, strong expandability, low cost and the like, and can be widely suitable for tera-hertz technical research, new material research, environmental detection and biomedical analysis. In the tera-hertz photoelectric characteristic test system, the light paths, circuits and control of the spectra and photoelectric response test system are subjected to design optimization and systematic integration; compact and reasonable optical, mechanical and vacuum cavity structures are designed; computer controlled accurate mechanical scanning and data acquisition are adopted; and finally the aim of testing and analyzing tera-hertz photoelectric characteristics of materials and core devices such as tera-hertz light sources and detectors by using combination of various light sources and detectors can be fulfilled.

A method for measuring film thickness distribution, including calculating profile P1 indicating wavelength dependence of a reflectance of a first wafer being an object measured with respect to a light at wavelengths not less than a wavelength region of visible light; calculating profile P21 indicating wavelength dependence of a reflectance of a second wafer to light at wavelengths not less than wavelength region of visible light; obtaining a wavelength λ1 observed when profile P31 of a difference between calculated profiles P1 and P21 becomes zero; and selecting waveband including the obtained wavelength λ1 as a waveband of light for use in film thickness distribution measurement by reflection spectroscopy. The film thickness distribution of the first thin film is measured by reflection spectroscopy in a manner that a surface of the first wafer is irradiated with a light to selectively measure only reflected light at a selected waveband.

To perform a monocular remote determination of a surface's three-dimensional orientation, an orientation-determination apparatus employs a radiation model in which the assumption is made that light incident upon the surface may be polarized but not elliptically. It makes polarimetric measurements of radiation received from the surface in each of a plurality of wavelength bands in the neighborhood of a known or inferable resonance in the surface's refractive-index spectrum. By employing the model, the apparatus matches the spectrum thus measured with the known behavior, in the neighborhood of a refractive-index resonance, of Fresnel-reflectance spectra as functions of incidence angle. Application-specific information is used to dispel minor ambiguities in the result.

The invention provides a method for quickly identifying tea varieties through a near-infrared spectroscopy technology. The method comprises the steps that firstly, near-infrared diffuse reflection spectrum of tea is collected through a near-infrared spectroscopy instrument, dimension reduction treatment is conducted on the high-dimension near-infrared spectrum of the tea through principal component analysis (PCA), the variety classification information of tea spectrum data is extracted through linear discriminant analysis (LDA), and finally, the tea varieties are identified and analyzed through a new generalized noise clustering method. The method is high in detection speed, high in identification accuracy, environmentally friendly and capable of accurately identifying the tea varieties.

The invention relates to a nondestructive testing method for the quality of compost products, comprising the following steps: 1) utilizing a near infrared ray diffuse reflectance spectrum collection device to collect near infrared ray diffuse reflectance spectrums of representative samples of the compost products, and converting spectrum information into corresponding digital information; 2) determining standard content of modeling; 3) implementing the extraction and pretreatment for characteristic spectrums on the near infrared ray diffuse reflectance spectrums obtained in the step 1), to result in optimal spectrum data information in the near infrared ray diffuse reflectance spectrums; 4) regarding a spectrum data point combination, preferably selected in the step 3), as an input vector, and based on support vector machine regression method in combination with leave-one-out cross validation method, establishing a correction model for the contents of major technical indexes of the near infrared ray diffuse reflectance spectrums of the compost products to be tested, in combination with standard contents of samples measured in the step 2); 5) evaluating the model; and 6) collecting and inputting the near infrared ray diffuse reflectance spectrums of the compost products to be tested to the correction model established in the step 4), and computing the contents of major technical indexes predicating the samples to be tested. The nondestructive testing method can perform rapid and efficient testing on the quality of organic fertilizer products after high-temperature aerobic composting and is suitable for the rapid and nondestructive high-accuracy quantitative testing for the major technical indexes of organic fertilizer products after the high-temperature aerobic composting of agricultural and forest remainders.

The invention discloses a tree leaf surface dust amount determination method and system, and belongs to the field of measurement and computer technology. The method comprises the following steps of building an estimatation equation and determining equation parameters, collecting leaf samples, weighing leaf weight by a one over ten-thousand analytical balance, measuring a reflected light spectrum of the leaves before dedusting by a portable spectrometer, removing dust on the leaf surfaces by deionized water, weighing leaf weight after dedusting, measuring a reflected light spectrum of the leaves after dedusting by the same method, acquiring spectrum parameters and building a relationship between the spectrum and leaf surface dust amount. The method can realize determination of leaf surface dust amount by the portable spectrometer without a high-precision electronic balance and thus the leaf surface dust amount can be estimated by the common spectrometer. The method is very suitable for plant pollution degree estimation and haze prevention and control measure optimization.

A method of characterizing conditions in a tissue, by (a) providing a catheter that has a light source that emits light in selected wavenumbers within the range of mid-IR spectrum; (b) directing the light from the catheter to an area of tissue at a location inside a blood vessel of a subject; (c) collecting light reflected from the location and generating a reflectance spectra; and (d) comparing the reflectance spectra to a reference spectra of normal tissue, whereby a location having an increased number of absorbance peaks at said selected wavenumbers indicates a tissue inside the blood vessel containing a physiological marker for atherosclerosis.

The invention relates to a method and apparatus of photo-modulation reflection spectroscopy based on step scan. The apparatus comprises a Fourier transform infrared spectrograph measuring system, a laser used as pump light source, a lock-in amplifier and a low-pass filter which connect the Fourier transform infrared spectrograph detector and the circuit controlling plate, wherein the circuit-breaker on the light path between the sample and the laser can transfer the constant pump laser into the modulated laser and feedback it in the reference end of the lock-in amplifier to control the lock-in.

The invention makes it possible to measure binding of a biochemical substance with a high throughput and with high sensitivity using a small cell capable of being filled with a small amount of chemical solution. A space between a first substrate and a second substrate such that probes are immobilized on their mutually facing planes is used as a cell that houses a specimen solution. Light is irradiated from a first substrate side, and reflected light is subjected to spectroscopy. Binding of the target with the probe is detected by a wavelength shift in the refection spectrum.

The invention provides a computer coloring method for color printing ink. The computer coloring method for color printing ink includes: setting a chromatic aberration value according to chromatic aberration requirements of a sample, adopting a Kubelka-Munk coloring method when the chromatic aberration is larger than 1.5, and adopting a neural network coloring method when the chromatic aberration is smaller than 1.5, wherein the Kubelka-Munk coloring method can be one of a spectrum vision matching method, a computer reflection spectroscopy and a computer coloring closing algorithm which are based on the Kubelka-Munk theory, and the neural network coloring method can be a computer coloring method based on a BP (back propagation) neural network. Favorable coloring methods can be chosen automatically according to different practical situations during color printing, and the computer coloring method for color printing ink is excellent in robustness and fault tolerance by the aid of the neural network technology.

A light source for near-infrared transmission and reflection spectroscopy can be constructed from a combination of a high power blue or blue-green light emitting diode (LED) and a phosphor element based on an inorganic material. The phosphor element absorbs the LED light and, in response to the LED excitation, emits luminescence that continuously covers the 700-1050 nm range. One possible material that can be used for such a near-infrared emitting phosphor element is a single crystal rod of Ti+3 doped Sapphire. An alternative near-infrared emitting phosphor material is a disk or rectangular shaped composite of Ti+3 doped Sapphire powder embedded in a clear optical epoxy or silicone encapsulant. Such a combination of a blue LED for excitation of a phosphor element that emits in a broad wavelength band has been widely used in white LEDs where the emission is in the 400-700 nm range.

A light source for near-infrared transmission and reflection spectroscopy can be constructed from a combination of a high power blue or blue-green light emitting diode (LED) and a phosphor element based on an inorganic material. The phosphor element absorbs the LED light and, in response to the LED excitation, emits luminescence that continuously covers the 700-1050 nm range. One possible material that can be used for such a near-infrared emitting phosphor element is a single crystal rod of Ti+3 doped Sapphire. An alternative near-infrared emitting phosphor material is a disk or rectangular shaped composite of Ti+3 doped Sapphire powder embedded in a clear optical epoxy or silicone encapsulant. Such a combination of a blue LED for excitation of a phosphor element that emits in a broad wavelength band has been widely used in white LEDs where the emission is in the 400-700 nm range.

The invention provides an acid-modified g-C3N4 photocatalyst and preparation and application thereof. glacial acetic acid and nitrogen-bearing organic matters are used as precursors to prepare the acid-modified g-C3N4 photocatalyst by means of impregnating-roasting; the acid-modified g-C3N4 photocatalyst is characterized via X-ray diffraction (XRD), photoluminescence spectroscopy (PL), infrared spectroscopy (IR), ultraviolet-visible light diffused reflection spectroscopy (UV-Vis DRS) and the like. The invention also relates to application of the acid-modified g-C3N4 photocatalyst; photocatalytic activity of the acid-modified g-C3N4 photocatalyst is evaluated by using methyl orange as a photocatalytic reaction model compound.

A total reflection spectroscopic measurement device includes a terahertz wave generation unit, an internal total reflection prism, a detection unit configured to detect the terahertz wave, an electric field vector measurement unit configured to measure an electric field vector of the terahertz wave, and an analysis unit configured to acquire information about an optical constant of the object to be measured. Proportions of S polarization component and P polarization component of the terahertz wave are constant. The analysis unit acquires the information about the optical constant on the basis of a ratio between S polarization component and P polarization component of the measured electric field vector when the object is not arranged on the total reflection surface and a ratio between S polarization component and P polarization component of the measured electric field vector when the object is arranged on the total reflection surface.

The invention discloses a method for determining oxide component content of cement raw meal by near infrared diffuse reflection spectrum. The method comprises the following steps of: determining the main oxide component content of the collected cement raw meal sample by adopting an X-ray fluorescence method to obtain the standard of each sample component; dividing the whole cement raw meal sampleinto a calibration set and a verification set to obtain the near infrared diffuse reflection spectrum thereof; performing smoothing processing on the near infrared diffuse reflection spectrum, establishing a calibration model by adopting a cooperation interval partial least square method, and determining the relation between the each sample content and the near infrared diffuse reflection spectrum; and performing external verification on the calibration model by using the verification set sample, comprehensively judging the model performance based on the calibration set correlation coefficient, the cross validation root mean square error, the verification set correlation coefficient, and the predicted root mean square error, and analyzing the correlation between a predicted value and a real value.

Spectroscopy apparatuses oriented to the critical angle of the sample are described that detecting the spectral characteristics of a sample wherein the apparatus consists of an electromagnetic radiation source adapted to excite a sample with electromagnetic radiation introduced to the sample at a location at an angle of incidence at or near a critical angle of the sample; a transmitting crystal in communication with the electromagnetic radiation source and the sample, the transmitting crystal having a high refractive index adapted to reflect the electromagnetic radiation internally; a reflector adapted to introduce the electromagnetic radiation to the sample at or near an angle of incidence near the critical angle between the transmitting crystal and sample; and a detector for detecting the electromagnetic radiation from the sample. Also, provided herein are methods, systems, and kits incorporating the peri-critical reflection spectroscopy apparatus.

A mid-IR spectrometer attachment performs reflection spectroscopy measurements using commercially available infinity corrected light microscopes without degrading the microscope's performance. The mid-IR spectrometer attachment, which is mounted to and supported by the visible light microscope, introduces infrared radiation into the optical path of the microscope. Radiation from the mid-IR spectrometer source is directed by a trichroic radiation director to a mid-IR objective lens affixed to the microscope nosepiece. The objective lens focuses the radiation on to a subject sample surface in order to acquire either internally or externally reflected infrared spectra by subsequently directing the sample encoded reflected mid-infrared radiation to the radiation director and then to a mid-infrared radiation detection system. The trichroic radiation director can reflect mid-IR, act as a beam splitter for near-IR and transmit visible light to allow the area of mid-IR spectroscopic analysis to be viewed in either visible light or near-IR.

The embodiment of the invention discloses a nondestructive testing method and device for fruits. The method comprises the steps of obtaining a first total diffuse reflection spectrum of a detected fruit, extracting a first diffuse reflection spectrum for predicting the content of fruit peel ingredients in fruit peel from the first total diffuse reflection spectrum, removing the first diffuse reflection spectrum from the first total diffuse reflection spectrum to obtain a second diffuse reflection spectrum; and extracting a third diffuse reflection spectrum for predicting the content of pulp ingredients in pulp from the second diffuse reflection spectrum. The first diffuse reflection spectrum is related to the fruit peel ingredients in the fruit peel and the third diffuse reflection spectrum is only related to the pulp ingredients in the pulp, so that the influence of the spectrum generated from the ingredients in the pulp is avoided through predicting the fruit peel ingredients in the fruit peel through the first diffuse reflection spectrum; and the influence of the spectrum generated from the ingredients in the fruit peel is also avoided through predicting the pulp ingredients in the pulp through the third diffuse reflection spectrum, thereby improving the accuracy of predicting the content of the ingredients in the fruit.

A method of inspecting food which can evaluate quality of the food with improved precision includes steps of irradiating probing light having near infrared wavelengths on the food; detecting light diffusively reflected by the food to obtain a reflectance spectrum; obtaining an absorbance spectrum based on the reflectance spectrum; and evaluating the food using the reflectance spectrum and the absorbance spectrum. An apparatus for implementing the method includes: a light source unit to generate probing light which has near infrared wavelengths and illuminates the food; a detector unit to detect light diffusively reflected by the food to obtain a reflectance spectrum of the food; and a processing unit to evaluate the food based on the reflectance spectrum and an absorbance spectrum calculated from the reflectance spectrum.