1315 results about "Spectral bands" patented technology

Apparatus, method, logic arrangement and storage medium are provided for increasing the sensitivity in the detection of optical coherence tomography and low coherence interferometry (“LCI”) signals by detecting a parallel set of spectral bands, each band being a unique combination of optical frequencies. The LCI broad bandwidth source can be split into N spectral bands. The N spectral bands can be individually detected and processed to provide an increase in the signal-to-noise ratio by a factor of N. Each spectral band may be detected by a separate photo detector and amplified. For each spectral band, the signal can be band p3 filtered around the signal band by analog electronics and digitized, or, alternatively, the signal may be digitized and band pass filtered in software. As a consequence, the shot noise contribution to the signal is likely reduced by a factor equal to the number of spectral bands, while the signal amplitude can remain the same. The reduction of the shot noise increases the dynamic range and sensitivity of the system.

A reagentless whole-blood analyte detection system that is capable of being deployed near a patient has a source capable of emitting a beam of radiation that includes a spectral band. The whole-blood system also has a detector in an optical path of the beam. The whole-blood system also has a housing that is configured to house the source and the detector. The whole-blood system also has a sample element that is situated in the optical path of the beam. The sample element has a sample cell and a sample cell wall that does not eliminate transmittance of the beam of radiation in the spectral band.

A reagentless whole-blood analyte detection system that is capable of being deployed near a patient has a source capable of emitting a beam of radiation that includes a spectral band. The whole-blood system also has a detector in an optical path of the beam. The whole-blood system also has a housing that is configured to house the source and the detector. The whole-blood system also has a sample element that is situated in the optical path of the beam. The sample element has a sample cell and a sample cell wall that does not eliminate transmittance of the beam of radiation in the spectral band.

The invention describes several embodiments of an adapter which can make use of the devices in any commercially available digital cameras to accomplish different functions, such as a fundus camera, as a microscope or as an en-face optical coherence tomography (OCT) to produce constant depth OCT images or as a Fourier domain (channelled spectrum) optical coherence tomography to produce a reflectivity profile in the depth of an object or cross section OCT images, or depth resolved volumes. The invention admits addition of confocal detection and provides simultaneous measurements or imaging in at least two channels, confocal and OCT, where the confocal channel provides an en-face image simultaneous with the acquisition of OCT cross sections, to guide the acquisition as well as to be used subsequently in the visualisation of OCT images. Different technical solutions are provided for the assembly of one or two digital cameras which together with such adapters lead to modular and portable high resolution imaging systems which can accomplish various functions with a minimum of extra components while adapting the elements in the digital camera. The cost of such adapters is comparable with that of commercial digital cameras, i.e. the total cost of such assemblies of commercially digital cameras and dedicated adapters to accomplish high resolution imaging are at a fraction of the cost of dedicated stand alone instruments. Embodiments and methods are presented to employ colour cameras and their associated optical sources to deliver simultaneous signals using their colour sensor parts to provide spectroscopic information, phase shifting inferometry in one step, depth range extension, polarisation, angular measurements and spectroscopic Fourier domain (channelled spectrum) optical coherence tomography in as many spectral bands simultaneously as the number of colour parts of the photodetector sensor in the digital camera. In conjunction with simultaneous acquistion of a confocal image, at least 4 channels can simultaneously be provided using the three color parts of conventional color cameras to deliver three OCT images in addition to the confocal image.

An imaging system, comprising a broadband unpolarized white light source (81), a polarization converter system for converting polarization axes of unpolarized white light into a substantially single polarization axis, to produce a beam of polarized light, a selective polarization filter (82), adapted to selectively rotate a polarization axis of a selected spectral band of light of the with respect to remaining polarized light based on a control signal (119), a polarized beam splitter (84), for separating light having a the substantially single polarization axis from light having a rotated polarization axis, a pair of electro-optic spatial light modulators (86, 89), disposed along a path of light within the spectral band and a path of remaining light outside the spectral band, respectively, and being adapted to modulate an image therein, and a polarized beam splitter (88), for recombining modulated light from the pair of light modulators. In a preferred embodiment, the selective polarization filter (82, 72) is divided into a plurality of regions (70, 71), each adapted to independently and selectively rotate a polarization axis of a selected spectral band of light of the with respect to remaining polarized light.

A reagentless whole-blood analyte detection system that is capable of being deployed near a patient has a source capable of emitting a beam of radiation that includes a spectral band. The whole-blood system also has a detector in an optical path of the beam. The whole-blood system also has a housing that is configured to house the source and the detector. The whole-blood system also has a sample element that is situated in the optical path of the beam. The sample element has a sample cell and a sample cell wall that does not eliminate transmittance of the beam of radiation in the spectral band.

An imaging system has a single focal plane array that does not require the precise alignment of multiple cameras relative to one another. It incorporates a multi-band, band pass filter that includes filter elements corresponding to pixel regions of a detector within a camera. The imaging system may further incorporate a detector that vertically discriminates among radiation in different spectral bands incident on an image plane of the detector. In this manner, spectral content may be determined in each spatial region without the need for beam splitting or multiple cameras. The filter itself may further comprise different filter elements, for example, filter elements A and B arranged in a checkerboard pattern, where filter element A passes different spectral bands than filter element B. In this manner, multi-spectral, high resolution images may be generated using a single camera that significantly improves upon image discrimination as compared to, for example, the Bayer color filter array pattern. The single camera implementation is well suited for incorporation into marine, land and air vehicles.

The invention provides a device and process for real-time screening of areas that can be identified as suspicious either through image segmentation utilizing image processing techniques or through treatment with an exogenous fluorescent marker that selectively localizes in abnormal areas. If screening detects a suspicious area, then the invention allows acquiring of autofluorescence images at multiple selected narrow differentiating spectral bands so that a "virtual biopsy" can be obtained to differentiate abnormal areas from normal areas based on differentiating portions of autofluorescence spectra. Full spatial information is collected, but autofluorescence data is collected only at the selected narrow spectral bands, avoiding the collection of full spectral data, so that the speed of analysis is increased.

A hyperspectral imaging system, including: at least one hyperspectral imaging unit, including: at least one lens configured to direct light scattered by, reflected by, or transmitted through a target medium to at least one hyperspectral filter arrangement configured to separate the light into discrete spectral bands; an imaging sensor to: receive the discrete spectral bands from the at least one hyperspectral filter arrangement; detect light by a plurality of pixels for each of the spectral bands; and generate electrical signals based at least in part on at least a portion of the light; and at least one image processor in communication with the at least one imaging sensor and configured to generate hyperspectral image data associated with the target medium; and at least one processor configured to determine biological data based at least partially on at least a portion of the hyperspectral image data.

Disclosed are an improved system and a related method for compensating the chromatic dispersion of a given length of a transmission fiber over a given spectral band by employing at least two chromatic dispersion compensating fibers that, with respect to the slope of the slope of the chromatic dispersion (SSi), have values of opposite signs.

A sound masking system for shaping the ambient noise level in a physical environment. The sound masking system comprises a networked and distributed system having a number of master units coupled together and to a control unit. One or more of the master units may include satellite sound masking units which function to reproduce the sound masking signal generated by the master sound masking unit. Each of the master units is addressable over the network by the control unit enabling the control unit to program the contour, spectral band, and gain characteristics of the sound masking output signal. The system may also include a remote control unit which provides the capability to tune and adjust each master sound masking unit in situ without requiring physical access through the ceiling installation.

A MOS or CMOS sensor for high performance imaging in broad spectral ranges including portions of the infrared spectral band. These broad spectral ranges may also include portions or all of the visible spectrum, therefore the sensor has both daylight and night vision capabilities. The sensor includes a continuous multi-layer photodiode structure on a many pixel MOS or CMOS readout array where the photodiode structure is chosen to include responses in the near infrared spectral ranges. A preferred embodiment incorporates a microcrystalline copper indium diselenide / cadmium sulfide photodiode structure on a CMOS readout array. An alternate preferred embodiment incorporates a microcrystalline silicon germanium photodiode structure on a CMOS readout array. Each of these embodiments provides night vision with image performance that greatly surpasses the GEN III night vision technology in terms of enhanced sensitivity, pixel size and pixel count. Further advantages of the invention include low electrical bias voltages, low power consumption, compact packaging, and radiation hardness. In special preferred embodiments CMOS stitching technology is used to provide multi-million pixel focal plane array sensors. One embodiments of the invention made without stitching is a two-million pixel sensor. Other preferred embodiments available using stitching techniques include sensors with 250 million (or more) pixels fabricated on a single wafer. A particular application of these very high pixel count sensors is as a focal plane array for a rapid beam steering telescope in a low earth orbit satellite useful for tracking over a 1500-meter wide track with a resolution of 0.3 meter.

A system for detecting airborne agents. The system can include a laser source that provides laser pulses of at least two wavelengths, a transmitter that transmits the laser pulses, and a coupling mechanism configured to remotely couple the laser pulses between the laser source and the transmitter. The system can include a receiver receives both elastically backscattered signals from airborne agents and fluorescence signals from the airborne agents. The system can include a telescope both transmits a collimated laser beam of the laser pulse from the transmitter to a far field and receives the elastically backscattered signals and the fluorescence signals from the far field. The system can include a detection system having at least one of a backscatter optical detector that detects the elastically backscattered signals and one or more fluorescence optical detectors that detect the fluorescence signals in selected spectral band(s) from the airborne agents.

An apparatus and method are disclosed for decreasing the spectral bandwidth of a semiconductor laser, such as a vertical cavity surface emitting laser.

The invention relates to an irradiation device and method for the treatment of totally or partially cell-mediated inflammations of the skin, the connective tissue and the viscera, viral and other infectious diseases such as HIV and prionic infections, fungal infections of the skin and the mucous membranes, bacterial diseases of the skin and the mucous membranes as well hand eczema and anal eczema which comprises at least one irradiation device to irradiate a surface treatment area where the wavelength of the emitted radiation to a treatment area is longer than 400 nm and comprises at least one spectral band between 400-500 nm while the radiation device contains means for the generation of optical pulses towards a treatment area with a power density of the optical pulse peaks larger than 0.5 W / cm2 and smaller than 100 kW / cm2. The energy of one pulse relates to 0.05-10 J / cm2.

Apparatus and method for increasing the sensitivity in the detection of optical coherence tomography and low coherence interferometry (“LCI”) signals by detecting a parallel set of spectral bands, each band being a unique combination of optical frequencies. The LCI broad bandwidth source is split into N spectral bands. The N spectral bands are individually detected and processed to provide an increase in the signal-to-noise ratio by a factor of N. Each spectral band is detected by a separate photo detector and amplified. For each spectral band the signal is band pass filtered around the signal band by analog electronics and digitized, or, alternatively, the signal may be digitized and band pass filtered in software. As a consequence, the shot noise contribution to the signal is reduced by a factor equal to the number of spectral bands. The signal remains the same. The reduction of the shot noise increases the dynamic range and sensitivity of the system.

Apparatus and method for increasing the sensitivity in the detection of optical coherence tomography and low coherence interferometry (“LCI”) signals by detecting a parallel set of spectral bands, each band being a unique combination of optical frequencies. The LCI broad bandwidth source is split into N spectral bands. The N spectral bands are individually detected and processed to provide an increase in the signal-to-noise ratio by a factor of N. Each spectral band is detected by a separate photo detector and amplified. For each spectral band the signal is band pass filtered around the signal band by analog electronics and digitized, or, alternatively, the signal may be digitized and band pass filtered in software. As a consequence, the shot noise contribution to the signal is reduced by a factor equal to the number of spectral bands. The signal remains the same. The reduction of the shot noise increases the dynamic range and sensitivity of the system.

The present invention further relates to the selection of the specific filter combinations, which can provide sufficient information for multivariate calibration to extract accurate analyte concentrations in complex biological systems. The present invention also describes wavelength interval selection methods that give rise to the miniaturized designs. Finally, this invention presents a plurality of wavelength selection methods and miniaturized spectroscopic apparatus designs and the necessary tools to map from one domain (wavelength selection) to the other (design parameters). Such selection of informative spectral bands has a broad scope in miniaturizing any clinical diagnostic instruments which employ Raman spectroscopy in particular and other spectroscopic techniques in general.

A two-dimensional focal plane array (FPA) is divided into sub-arrays of rows and columns of pixels, each sub-array being responsive to light energy from a target object which has been separated by a spectral filter or other spectrum dividing element into a predetermined number of spectral bands. There is preferably one sub-array on the FPA for each predetermined spectral band. Each sub-array has its own read out channel to allow parallel and simultaneous readout of all sub-arrays of the array. The scene is scanned onto the array for simultaneous imaging of the terrain in many spectral bands. Time Delay and Integrate (TDI) techniques are used as a clocking mechanism within the sub-arrays to increase the signal to noise ratio (SNR) of the detected image. Additionally, the TDI length (i.e., number of rows of integration during the exposure) within each sub-array is adjustable to optimize and normalize the response of the photosensitive substrate to each spectral band. The array provides for parallel and simultaneous readout of each sub-array to increase the collection rate of the spectral imagery. All of these features serve to provide a substantial improvement in the area coverage of a hyperspectral imaging system while at the same time increasing the SNR of the detected spectral image.

MRI scans typically have higher resolution within a slice than between slices. To improve the resolution, two MRI scans are taken in different, preferably orthogonal, directions. The scans are registered by maximizing a correlation between their gradients and then fused to form a high-resolution image. Multiple receiving coils can be used. When the images are multispectral, the number of spectral bands is reduced by transformation of the spectral bands in order of image contrast and using the transformed spectral bands with the highest contrast.

A method samples a first spectral band to obtain an initial image frame, determines at least one region of interest of the scene from the initial image frame, each of the at least one region of interest associated with a mean signal level, illuminates the at least one region of interest with at least one illuminator when the mean signal level of the at least one region of interest is at or below a respective threshold of a first plurality of thresholds, the at least one region of interest being illuminated in accordance with a power threshold indicating a minimum illuminator power and agility necessary to illuminate the at least one region of interest, collects at least one image frame in at least one sub-band of a second spectral band, and generates at least one image to be displayed from at least the at least one image frame.

Systems and methods in accordance with embodiments of the invention utilize array cameras incorporating quantum dot color filters. One embodiment includes: lens elements formed on substrates separated by spacers, where the lens elements, substrates and spacers form a plurality of optical channels; at least one aperture located within each optical channel; at least one spectral filter located within each optical channel, where each spectral filter is configured to pass a specific spectral band of light; and at least one quantum dot color filter located within each optical channel to receive the specific spectral band of light passed by the at least one spectral filter located within the optical channel, where the at least one quantum dot color filter is configured to emit a spectral band of light having a bandwidth that is narrower than the specific spectral band of light passed by the at least one spectral filter.

A method samples a first spectral band to obtain an initial image frame, determines at least one region of interest of the scene from the initial image frame, each of the at least one region of interest associated with a mean signal level, illuminates the at least one region of interest with at least one illuminator when the mean signal level of the at least one region of interest is at or below a respective threshold of a first plurality of thresholds, the at least one region of interest being illuminated in accordance with a power threshold indicating a minimum illuminator power and agility necessary to illuminate the at least one region of interest, collects at least one image frame in at least one sub-band of a second spectral band, and generates at least one image to be displayed from at least the at least one image frame.

An amplification system and method is provided that reduces peaks associated with an input signal, and provides correction, in one or more spectral bands, to signal distortion and out-of-band emissions that result from the peak reduction. The correction signal that removes signal distortion and OOB emissions associated with the peak reduction can be calculated or electronically derived. The correction signal can be combined with the peak reduced signal prior to or after amplification of the peak reduced input signal.

What is disclosed is a system and method for monitoring respiration of a subject or subject of interest using a thermal imaging system with single or multiple spectral bands set to a temperature range of a facial region of that person. Temperatures of extremities of the head and face are used to locate facial features in the captured thermal images, i.e., nose and mouth, which are associated with respiration. The RGB signals obtained from the camera are plotted to obtain a respiration pattern. From the respiration pattern, a rate of respiration is obtained. The system includes display and communication interfaces wherein alerts can be activated if the respiration rate falls outside a level of acceptability. The teachings hereof find their uses in an array of devices such as, for example, devices which monitor the respiration of an infant to signal the onset of a respiratory problem or failure.

An apparatus and method for the phototherapy of different skin conditions, particularly acne vulgaris and seborrhea. The invention transporting compounds, and / or a methylene blue solution. The apparatus includes at least one narrow spectral band light source with spectral emittance concentrated in the violet / blue spectral band and an optical system for controlling spectra and beam parameters of said light source and a mechanical fixture for holding the said light source at an adjustable distance and direction related to the skin treated area, and an electonic unit to control the duration and power and spectral bands of the emitted radiation.