1754 results about "Excitation wavelength" patented technology

An endoscopic video system and method using a camera with a single color image sensor, for example a CCD color image sensor, for fluorescence and color imaging and for simultaneously displaying the images acquired in these imaging modes at video rates in real time is disclosed. The tissue under investigation is illuminated continuously with fluorescence excitation light and is further illuminated periodically using visible light outside of the fluorescence excitation wavelength range. The illumination sources may be conventional lamps using filters and shutters, or may include light-emitting diodes mounted at the distal tip of the endoscope.

A system and a method of a transparent color image display utilizing fluorescence conversion (FC) of nano-particles and molecules are disclosed. In one preferred embodiment, a color image display system consists of a light source equipped with two-dimensional scanning hardware and a FC display screen board. The FC display screen board consists of a transparent fluorescence display layer, a wavelength filtering coating, and an absorption substrate. In another preferred embodiment, two mechanisms of light excitation are utilized. One of the excitation mechanisms is up-conversion where excitation light wavelength is longer than fluorescence wavelength. The second mechanism is down-conversion where excitation wavelength is shorter than fluorescence wavelength. A host of preferred fluorescence materials for the FC screen are also disclosed. These materials fall into four categories: inorganic nanometer sized phosphors; organic molecules and dyes; semiconductor based nano particles; and organometallic molecules. These molecules or nano-particles are incorporated in the screen in such a way that allows the visible transparency of the screen. Additionally, a preferred fast light scanning system is disclosed. The preferred scanning system consists of dual-axes acousto-optic light deflector, signal processing and control circuits equipped with a close-loop image feedback to maintain position accuracy and pointing stability of the excitation beam.

System and method for tracking and control in medical procedures. The system including a device that deploys fluorescent material on at least one of an organ under surgery and a surgical tool, a visual light source, a fluorescent light source corresponding to an excitation wavelength of the fluorescent material, an image acquisition and control element that controls the visual light source and the fluorescent light source, and captures and digitizes at least one of resulting visual images and fluorescent images, and an image-based tracking module that applies image processing to the visual and fluorescent images, the image processing detecting fluorescent markers on at least one of the organ and the surgical tool.

The invention realizes a phosphor film that has a fluorescent characteristic excellent in resistance to humidity and provides, using the phosphor film, a liquid crystal display device that is excellent in resistance to humidity and has satisfactory calorimetric property and color mixture property. Phosphor particles that are excited by incident light and emit light having a wavelength different from the incident light are mixed in a binder. The binder mixed with the phosphor particles is sandwiched between a translucent film and a non-permeable layer as a phosphor layer to form a phosphor film. This phosphor film is provided at least in one place among a place between a light source and a light guide of a lighting device, a place on a light irradiation surface of the light guide, and a place between the light guide and a reflection plate. Moreover, the phosphor particles have a characteristic that a wavelength absorbed by a color filter of a display element is set as an excitation wavelength and a luminescent wavelength is in a region transmitted by the color filter. With this phosphor film, it is possible to realize a display device that has extremely high luminance efficiency and color reproducibility.

A device for supporting chromophore elements suitable for emitting fluorescence in response to light excitation, the device comprising a substrate having a surface layer carrying the chromophore elements, forming a planar waveguide, and containing photoluminescent constituents which emit guided luminescence at the excitation wavelength(s) of the chromophore elements when they are excited by primary excitation light illuminating the surface layer. The invention is particularly applicable to biochip type devices.

Methods and apparatus for qualifying and quantifying excitation-dependent physiological information extracted from wearable sensors in the midst of interference from unwanted sources are provided. An organism is interrogated with at least one excitation energy, energy response signals from two or more distinct physiological regions are sensed, and these signals are processed to generate an extracted signal. The extracted signal is compared with a physiological model to qualify and/or quantify a physiological property. Additionally, important physiological information can be qualified and quantified by comparing the excitation wavelength-dependent response, measured via wearable sensors, with a physiological model.

A method based on time-resolved, laser-induced fluorescence spectroscopy for the characterization and fingerprinting of petroleum oils and other complex mixtures. The method depends on exciting the wavelength-resolved fluorescence spectra of samples using ultraviolet pulsed laser radiation, measuring them at specific time gates within the temporal response of the excitation laser pulse, and comparing them in terms of their shapes alone without taking into account their relative intensities. The method provides fingerprints of crude oils without resorting to any kind of approximation, for distinguishing between closely similar crude oils of the same grade, and is useful in remote and non-remote setups, along with applications in fingerprinting blended and non-blended crude oils using different ultraviolet excitation wavelengths. Applications include estimating °API gravity of crude oils and monitoring degradation of mineral oils.

An improvement in a method for quantitative modulated imaging to perform depth sectioned reflectance or transmission imaging in a turbid medium, such as human or animal tissue is directed to the steps of encoding periodic pattern of illumination preferably with a fluorescent excitation wavelength when exposing a turbid medium to the periodic pattern to provide depth-resolved discrimination of structures within the turbid medium; and reconstructing a non-contact three dimensional image of the structure within a turbid medium. As a result, wide field imaging, separation of the average background optical properties from the heterogeneity components from a single image, separation of superficial features from deep features based on selection of spatial frequency of illumination, or qualitative and quantitative structure, function and composition information is extracted from spatially encoded data.

A fluorescence diagnosis system has a viewing system at least one light source and a camera system. The at least one light source can be operated in three modes, a first generating white light, a second with a first fluorescence excitation light of a first excitation wavelength and a third in which a second fluorescence excitation light of a second excitation wavelength is generated producing a fluorescence image in the NIR range. The camera system is sensitive at least in the visible and the NIR range. The system further comprises an image processing system for converting the fluorescence image in the NIR range into a visible image.

The present invention provides ratiometric fluorescent pH sensors for non-invasive, continuous monitoring of pH in such applications as fermentation processes. The ratiometric fluorescent pH sensors comprise a fluorescent dye that exhibits a shift in excitation wavelength with a corresponding shift in pH in the local environment of said fluorescent dye. Ratiometric measurements of the emission intensities at dual excitation maxima correlate to pH. Also provided is a fluorescent dye 6-methacryloyl-8-hydroxy-1,3-pyrene disulfonic acid (MA-HPDS). Further provided are systems and methods to non-invasively and continuously monitor pH.

A method for the conduct of a measurement of proximity between luminescent species based on detection of transfer of excitation energy between them. A first photoluminescent species (the "donor") and a second photoluminescent species (the "acceptor") are provided and are such that the donor species and the acceptor species have at least some excitation spectral regions which differ and that at least a part of the emission spectrum of the donor overlaps with at least a part of the excitation spectrum of the acceptor. The donor species is excited with a cyclical temporal sequence of wavelength bands, optionally provided as pulses or modulated in intensity, giving rise to a characteristic temporal fluctuation in emission therefrom and emission in at least one wavelength band characteristic of the acceptor is analyzed to detect the presence of the said characteristic fluctuation or a subcomponent thereof and optionally also to detect a fluctuation characteristic of direct excitation of the acceptor.

The relative intensity of fluorescent light of a melt-polycondensed aromatic polycarbonate produced by the transesterification process (melt polymerization process) of an aromatic dihydroxy compound and a carbonic acid diester in the presence of a catalyst comprising a basic nitrogen compound and/or a basic phosphorus compound in combination with an alkali metal compound is suppressed to 4.0x10-3 or below at a wavelength of 465 nm based on a standard substance in a fluorescent light spectrum obtained by the excitation wavelength of 320 nm. An aromatic polycarbonate having good color stability, especially good stability to the deterioration of the chip color during storage of the chip in air at room temperature can be produced by the present invention.

A light source device includes a first light source 33, a second light source 35 having an emission wavelength that is different from the first light source 33, and a phosphor 43 that is disposed to be distant from the first light source 33 and the second light source 35 and absorbs light in a predetermined excitation wavelength band to emit fluorescence. The phosphor 43 is disposed on an emission light optical path that is shared by the first light source 33 and the second light source 35. The emission wavelength of the first light source 33 is in the predetermined excitation wavelength band. The emission wavelength of the second light source 35 is outside of the predetermined excitation wavelength band.

Methods and systems for detecting early stage dental caries and decays are provided. In particular, in an embodiment, laser-induced autofluorescence (AF) from multiple excitation wavelengths is obtained and analyzed. Endogenous fluorophores residing in the enamel naturally fluoresce when illuminated by wavelengths ranging from ultraviolet into the visible spectrum. The relative intensities of the AF emission changes between different excitation wavelengths when the enamel changes from healthy to demineralized. By taking a ratio of AF emission spectra integrals between different excitation wavelengths, a standard is created wherein changes in AF ratios within a tooth are quantified and serve as indicators of early stage enamel demineralization. The techniques described herein may be used in conjunction with a scanning fiber endoscope (SFE) to provide a reliable, safe and low-cost means for identifying dental caries or decays.

Apparatus and methods for optical illumination and/or detection with improved flexibility and/or read speed. The apparatus and methods may include mechanisms for selecting and switching between multiple excitation wavelengths and/or simultaneously reading from a plurality of sample sites. The apparatus and methods may be used with microplates, PCR plates, cell culture plates, biochips, chromatography plates, microscope slides, and other substrates for high-throughput screening, genomics, SNPs analysis, pharmaceutical research and development, life sciences research, and other applications.

A thermal transfer printing medium that contains a thermal transfer layer which contains a first taggant and colorant, wherein: the first taggant comprises a fluorescent compound with an excitation wavelength selected from the group consisting of wavelengths of less than 400 nanometers, wavelengths of greater than 700 nanometers. When the thermal transfer layer is printed onto a white polyester substrate with a gloss of at least about 84, a surface smoothness Rz value of 1.2, and a reflective color represented by a chromaticity (a) of 1.91 and (b) of −6.79 and a lightness (L) of 95.63, when expressed by the CIE Lab color coordinate system, and when such printing utilizes a printing speed of 2.5 centimeters per second and a printing energy of 3.2 joules per square centimeter, a printed substrate with certain properties is produced. The printed substrate has a reflective color represented by a chromaticity (a) of from −15 to 15 and (b) from −18 to 18, and the printed substrate has a lightness (L) of less than about 35, when expressed by the CIE Lab color coordinate system. When the printed substrate is illuminated with light source that excites the first taggant with an excitation wavelength selected from the group consisting of wavelengths of less than 400 nanometers, wavelengths greater than 700 nanometers, the printed substrate produces a light fluorescence with a wavelength of from about 300 to about 700 nanometers.

A fluorescence light scanning microscope (2) comprises a light source providing excitation light (8) for exciting a fluorophore in a sample to be imaged for spontaneous emission of fluorescence light, and suppression light (7) for suppressing spontaneous emission of fluorescence light by the fluorophore on a common optical axis (4), the suppression wavelength differing from the excitation wavelength; an objective (19) focusing both the excitation (8) and the suppression (7) light to a focus point; a detector (21) detecting fluorescence light (11) spontaneously emitted by the fluorophore; and a chromatic beam shaping device (1) arranged on the common optical axis (4), and including a birefringent chromatic optical element (3) adapted to shape a polarization distribution of the suppression light (7) such as to produce an intensity zero at the focus point, and to leave the excitation light such as to produce a maximum at the focus point.