1081 results about "Reflection spectrum" patented technology

A catheter based method and apparatus for reflectance generated absorption spectral analysis of chronic inflammatory vascular conditions such as seen with atherosclerotic plaque within a blood vessel or other body cavity or compartment. The use of a bright mid range infrared light (mid-IR) source yields detectable reflected optical signals that may be sampled from an area smaller or larger than the typical diameter of a mammalian cell. The mid-IR light is delivered at selected mid-infrared wavenumbers. Using the apparatus and methods, the reflectance spectra and reflectance generated absorption spectra of a target tissue can be compared to reference spectra to identify and distinguish normal epithelium from tissue containing physiological markers indicative of vascular disease or other inflammatory conditions.

In accordance with the invention, a low coherence interferometer is used to non-invasively monitor the concentration of glucose in blood by shining a light over a surface area of human or animal tissue, continuously scanning the light over a two dimensional area of the surface, collecting the reflected light from within the tissue and constructively interfering this reflected light with light reflected along a reference path to scan the tissue in depth. Since the reflection spectrum is sensitive to glucose concentration at particular wavelengths, measurement and analysis of the reflected light provides a measure of the level of glucose in the blood. The measurement of glucose is taken from multiple depths within blood-profused tissue, and sensitivity is preferably enhanced by the use of multiple wavelengths. Noise or speckle associated with this technique is minimized by continuously scanning the illuminated tissue in area and depth.

A device to provide hyperspectral reflection spectrum, hyperspectral depolarization, and hyperspectral fluorescence spectrum data in a portable, remote sensing instrument. The device can provide a large range of remotely-sensed optical property data, presently only obtainable in laboratories, in a low-cost field instrument. Among its many uses, the present invention can be used by farmers as a tool for determining the nitrogen content of crops to optimize fertilizer laydown.

A method and equipment for detecting an explosive, etc. are disclosed. A specified portion highly likely to contain an explosive, etc. is extracted based on the X-ray image obtained by radiating an X ray on an object to be inspected. An electromagnetic wave containing the terahertz wave is radiated on the specified portion thus extracted. The presence or absence of the explosive, etc. is determined based on at least one of the absorption spectrum and the reflection spectrum of the electromagnetic wave at the specified portion.

The present invention facilitates the calibration of printers and the color separation of input images into a set of inks by disclosing methods and systems for populating device-calibration lookup tables. The disclosed methods and systems rely on a comprehensive spectral prediction model which is capable of predicting at a high accuracy the reflectance spectra of halftone ink patches. The comprehensive spectral prediction model is composed of a first part predicting the reflection spectra as a function of physical (mechanical) surface coverages and of a second part comprising functions mapping nominal surface coverages to effective surface coverages. These mapping functions are calibrated by halftone patch wedges printed alone and by half-tone patch wedges printed in superposition with one or several solid inks. The part of the comprehensive spectral prediction model predicting the reflection spectra relies on a weighted average between one component behaving according to the Clapper-Yule model and another component behaving as the spectral Neugebauer model, extended to include multiple internal reflections at the paper-air boundary. The disclosed methods and systems can perform the color separation as well as the calibration of printers printing with standard cyan, magenta, and yellow inks as well as with inks comprising standard and non-standard inks such as Pantone inks (custom inks). They are also used for performing precise undercolour removal in order to carry out the color separation of images into cyan, magenta, yellow and black inks. They can further be used to carry out the color separation of images into cyan, magenta, yellow, black, light cyan and light magenta inks. In addition, the disclosed methods and systems can be used for printer control, i.e. to control printer actuation parameters in different types of printers e.g. liquid ink professional printers (offset, gravure, letterpress), electrophotographic printers, ink-jet printers, thermal transfer printers and in dye-sublimation printers.

A preferred embodiment biosensor is a multi-layer micro-porous thin film structure. Pores in a top layer of the micro-porous thin film structure are sized to accept a first molecule of interest. Pores in a second layer of the micro-porous thin film structure are smaller than the pores in the top layer and are sized to accept a second molecule of interest that is smaller than the first molecule of interest. The pores in the second layer are too small to accept the first molecule of interest. The pores in the top layer and the pores in the second layer are sized and arranged such that light reflected from the multi-layer micro-porous thin film structure produces multiple superimposed interference patterns that can be resolved. In preferred embodiments, the multi-layer micro-porous thin film structure is a porous silicon thin film multi-layer structure formed on a silicon substrate, such as a silicon wafer. Specific and nonspecific binding can be detected with biosensors of the invention. The position of peaks in the Fourier transform of the reflection spectrum and the shift in peak amplitudes can be used to determine the presence and quantity of targeted biological molecules of interest.

The invention relates to a lossless testing device for nitrogen nutritive index of crop leaves based on canopy reflection spectrum. It belongs to technology field of crop production, which is specially used in online detecting and precious fertilizing guidance of crop field production. It is mainly composed of bracket, spectrum signal collection and host computer. Spectrum signal collection adopts design of 4 waveband and 8 channels. Hardware system is composed of analog signals conditioning module, A/D transfer module, chip module, memory module, display module, keyboard module, communication module and power management module. Software system is programmed by C51 chip language. Detection of nitrogen content, nitrogen accumulation and leaf area index of canopy not only ensures high detecting precision, but also provides three data indexes of different facets to analyze nitrogen nutritive level of crop, which guarantees reliability and stability of detecting results. It can be applied in field operation, online lossless detecting, field online manage and guidance for agricultural production personnel.

The invention provides a method and system for measuring skin physiology parameters and optical property parameters based on reflective spectral measurement. The measuring system is composed of measuring equipment for a skin reflection spectrum and a computation and display device. By utilizing an analysis method of combining experimental data with the Monte Carlo simulation, the measuring system provides more accurate corresponding data of reflection light intensity and skin optical property; during the practical measurement of sample skin, on the basis of a practically measured reflection spectrum, the data and more physiology parameters are calculated and fit to obtain the skin physiology parameters and the optical property parameters based on reflective spectral measurement; finally, the optical property parameters of the skin adsorption coefficient mu a, a reduction scattering coefficient mu s' and the like as well as physiological information, such as melanin content, deoxygenated haemoglobin content, oxygenated haemoglobin content, moisture content and the like are also measured are measured in real time in a non-invasive and lossless mode.

The present invention generally relate to an anti-reflection film and a polarization plate containing the same, particularly relate to the anti-reflection film having an excellent rainbow effect and low reflectivity by reducing amplitude of reflection spectrum, and the polarization plate containing the anti-reflection film. The anti-reflection film includes a cellulose triacetate (TAC) transparent base for protecting a polyvinyl alcohol (PVA) polaroid sheet; a high-hardness layer coated on the transparent base and having a high refractivity of 1.50-1.60 as well as antistatic function; and a low refractivity layer coated on the high-hardness layer by a wet method and having a refractivity of 1.31-1.40, wherein the anti-reflection film has an average specular reflectance of 0.1-1.40% in a wavelength range from 480-680nm at an incidence angle of 5 DEG.

The present invention proposes a method and a computing system for deducing ink thickness variations from spectral reflectance measurements performed on a printing press or on a printer. The computed ink thickness variations enable controlling the ink deposition and therefore the color accuracy, both in the case of high-speed printing presses and of network printers. Ink thickness variations are expressed as ink thickness variation factors incorporated into a spectral prediction model. The method for computing ink thickness variations comprises both calibration and ink thickness variation computation steps. The calibration steps comprise the calculation of ink transmittances from measured reflectances and the computation of possibly wavelength-dependent ink thicknesses of solid superposed inks. Wavelength-dependent ink thicknesses account for the scattering behavior of non-transparent inks or of inks partly entering into the paper bulk. The ink thickness variation factors are fitted by minimizing a distance metric between the reflection spectrum predicted according to the thickness variation enhanced spectral prediction model and the measured reflection spectrum. The ink thickness variation enhanced spectral prediction model can be applied both in the visible wavelength range and in the near-infrared wavelength range. This enables computing unambiguously the thickness variations of the cyan, magenta, yellow and black inks. Furthermore, a spectral reflection may be measured over a stripe of a printed page and used to predict the ink thickness variations occurring within that stripe. This enables the real-time control of the ink deposition process on a printing press.

The invention discloses a single longitudinal-mode optical fiber laser with low noise, narrow linewidth and high power. Polarization maintaining optical fiber is rare-earth-doped phosphate single-mode glass optical fiber, the component of a fiber core is phosphate glass which consists of 70P2O5-8Al2O3-15BaO-4La2O3-3Nd2O3, the fiber core of the polarization maintaining optical fiber is doped with high-concentration luminous ions, the luminous ions are one or combination of more than one of lanthanide ions and transition metal ions, the doping density of the luminous ions is greater than 1*10<19>ions/cm<3> and the luminous ions are evenly doped in the fiber core. A polarization maintaining fiber Bragg grating with the narrow linewidth and a dichroscope form a front cavity mirror and a rear cavity mirror of the optical fiber laser, a centimeter-sized erbium-ytterbium co-doped phosphate glass polarization maintaining optical fiber is taken as a laser working substance, and polarization maintaining output laser generated by a single-mode semiconductor laser is taken as a pumping source, thus achieving the single longitudinal-mode laser output by designing and manufacturing the reflection spectrum width of the polarization maintaining fiber Bragg grating and controlling the cavity length of the whole laser cavity.

The invention provides a method for manufacturing intelligent composite-material laminates used for monitoring structural longitudinal strain. In order to solve the technical problems that as fiber grating sensors are bonded to the surface of a structure through polyimide resin or epoxy resin commonly used in the prior engineering, optic fiber in service is easily destroyed; the optic fiber can get encapsulation protection but cause the concentration of surrounding stress/strain thereof if the optic fiber is directly embedded in a composite-material structure; and thermal residual stress produced in a material-curing process can cause chirp phenomena of fiber grating reflection spectrum to affect the measurement accuracy of grating strain, and the like, the invention provides the method for manufacturing intelligent composite-material laminates used for monitoring structural longitudinal strain. In the method, the fiber grating sensors are embedded in composite-material layers to replace resistance strain gauges commonly used in the field of monitoring structural health; by applying prestress to embedded fiber gratings, the influence of the curing residual stress of composite material on the fiber grating reflection spectrum is reduced so as to avoid the chirp phenomena; and the stability and repeatability of the sensors are improved. In addition, the composite material plays a good role in encapsulating and protecting bare fiber gratings, and meets engineering construction requirement on sensor sensitivity.

The present invention provides a hard coat film in which the generation of interference fringes can be reliably prevented. The hard coat film 1 of the present invention includes a transparent film 2 and a hard coat layer 3 provided on the transparent film 2, wherein an interface 5 that can be detected to form by a reflection spectrum analysis exists between the transparent film 2 and the hard coat layer 3, and a refractive index continuously varies in the thickness direction in a region 31 from the interface 5 to a thickness-wise middle part of the hard coat layer 3 without forming an interface that can be detected by the reflection spectrum analysis.

The invention provides a fiber grating monitoring method for the curing residual strain of composite materials. The method comprises the following steps: (1) manufacturing a sensor string comprising grating temperature sensors and grating temperature strain sensors; (2) embedding fiber grating sensors in to-be-monitored parts of a composite material in the process of layering the composite material; (3) reasonably selecting a molding process for the composite material, such as hot-pressing reactor, compression molding and the like; (4) cooling the composite material to room temperature after curing molding is performed and using a grating demodulation instrument to monitor the wavelength value of the highest reflection peak of a reflection spectrum of a fiber grating; and (5) utilizing epsilon=1/k epsilon((delta lambda B1/lambda B1)-(Delta lambda B2/lambda B2)) to calculate the curing residual strain of the composite material. The method can realize the measurement of the residual strain of key parts of the structure of the composite material on the premise of not destroying the structure, and has the advantages of stable reliable measured values and good repeatability; in addition, the embedded grating can continue to play a role in monitoring the structure health of the composite material. The method organically combines the digital manufacturing and the health monitoring of the composite material, thereby realizing the on-line monitoring for the manufacturing process of the composite material.

A display device for driving liquid drops to move on the basis of an electrowetting effect is characterized by comprising a lower substrate, an electrode plate, a nano-metal grating, a plurality of liquid drops, a super-hydrophobic coating layer, a dielectric layer, an electrode array and an upper substrate in sequence from bottom to top. A cofferdam is added on the periphery between the upper substrate and the lower substrate to form a sealed chamber, the chamber is filled with a second fluid insoluble with the liquid drops, and the single liquid drops in a chamber between the electrode array and the electrode plate which are parallel to each other at least cover two adjacent electrodes of the electrode array. The characteristic that the nano-metal grating is extremely sensitive to changes of the refractive index of an adjacent material is utilized, color filtering is finished by changing the material refractive index, active modulation of transmission and reflection spectrums of the nano-metal grating is achieved, and simultaneously due to the hydrophobic characteristic of the nano-metal grating structure, the electrowetting display modulation contrast and speed can be improved.