99 results about "High resolution spectra" patented technology

The present invention provides an apparatus and method for high resolution spectroscopy (approximately 10 picometer wavelength resolution) using a tunable optical filter (TOF) for analyzing a formation fluid sample downhole and at the surface to determine formation fluid parameters. The analysis comprises determination of gas oil ratio, API gravity and various other fluid parameters which can be estimated after developing correlations to a training set of samples using a neural network or a chemometric equation.

The present invention provides a slit-scan multi-wavelength confocal lens module, which utilizes at least two lenses having chromatic aberration for splitting a broadband light into continuously linear spectral lights having different focal length respectively. The present invention utilizes the confocal lens module employing slit-scan confocal principle and chromatic dispersion techniques and the confocal microscopy with optical sectioning ability and high resolution in spectral dispersion to establish a confocal microscopy method and system with long DOF and high resolution, capable of modulating a broadband light to produce the axial chromatic dispersion and focus on different depths toward an object's surface for obtaining the reflected light spectrum from the surface. Thereafter, the spectrum is spatially filtered by a slit and then a peak position with respect to the filtered spectrum along the scanning line is detected by a spectral image sensing unit for generating the sectional profile of the measured surface.

A widely tunable, mode-hop-free semiconductor laser operating in the mid-IR comprises a QCL laser chip having an effective QCL cavity length, a diffraction grating defining a grating angle and an external cavity length with respect to said chip, and means for controlling the QCL cavity length, the external cavity length, and the grating angle. The laser of claim 1 wherein said chip may be tuned over a range of frequencies even in the absence of an anti-reflective coating. The diffraction grating is controllably pivotable and translatable relative to said chip and the effective QCL cavity length can be adjusted by varying the injection current to the chip. The laser can be used for high resolution spectroscopic applications and multi species trace-gas detection. Mode-hopping is avoided by controlling the effective QCL cavity length, the external cavity length, and the grating angle so as to replicate a virtual pivot point.

A frequency comb laser providing large comb spacing is disclosed. At least one embodiment includes a mode locked waveguide laser system. The mode locked waveguide laser includes a laser cavity having a waveguide, and a dispersion control unit (DCU) in the cavity. The DCU imparts an angular dispersion, group-velocity dispersion (GVD) and a spatial chirp to a beam propagating in the cavity. The DCU is capable of producing net GVD in a range from a positive value to a negative value. In some embodiments a tunable fiber frequency comb system configured as an optical frequency synthesizer is provided. In at least one embodiment a low phase noise micro-wave source may be implemented with a fiber comb laser having a comb spacing greater than about 1 GHz. The laser system is suitable for mass-producible fiber comb sources with large comb spacing and low noise. Applications include high-resolution spectroscopy.

A method and apparatus for treating a sample for acquiring high-definition magnetic resonance images (MRI images) or high resolution nuclear magnetic resonance (NMR) spectra even in the presence of magnetic field distortions within one or multiple scans. The spatial nature and temporal dependence of the field inhomogeneities are determined a priori using any of several literature procedures. A static or oscillating magnetic field gradient is applied on the sample so as to endow spins at different positions within the sample with different resonance frequencies. A phase- and amplitude-modulated radiofrequency (RF) pulse is applied in unison with the magnetic field gradient so as to endow spins at different positions within the sample with a homogeneous excitation/inversion profile. The nature of the spatially-selective RF irradiation is tailored in such a way that, when added on top of the effects of the inhomogeneities, the spins' evolution phases and their signal amplitudes at the time of the acquisition become independent of the inhomogeneities. The spin signals thus created are captured and decoded, so as to obtain the spins' response as if the inhomogeneity was not present. The collected data is processed to a suitable rearrangement and Fourier analysis procedure to retrieve a final undistorted image or spectrum. The magnetic field gradient can be oscillated to impose this kind of inhomogeneity corrections on multiple spatial dimensions sequentially, or simultaneously.

The present invention provides a simple, robust, and versatile high-resolution spectrometer that is suitable for downhole use. The present invention provides a method and apparatus incorporating a spinning, oscillating or stepping optical interference filter to change the angle at which light passes through the filters after passing through a sample under analysis downhole. As each filter is tilted, the color or wavelength of light passed by the filter changes. Black plates are placed between the filters to isolate each filter's photodiode. The spectrometer of the present invention is suitable for use with a wire line formation tester, such as the Baker Atlas Reservation Characterization Instrument to provide supplemental analysis and monitoring of sample clean up. The present invention is also suitable for deployment in a monitoring while drilling environment. The present invention provides a high resolution spectometer which enables quantification of a crude oil's percentage of aromatics, olefins, and saturates to estimate a sample's gas oil ratio (GOR). Gases such as CO₂ are also detectable. The percentage of oil-based mud filtrate contamination in a crude oil sample can be estimated with the present invention by using a suitable training set and chemometrics, a neural network, or other type of correlation method.

The present invention provides a simple, robust, and versatile high-resolution spectrometer that is suitable for downhole use. The present invention provides a method and apparatus incorporating a spinning, oscillating or stepping optical interference filter to change the angle at which light passes through the filters after passing through a sample under analysis downhole. As each filter is tilted, the color or wavelength of light passed by the filter changes. Black plates are placed between the filters to isolate each filter's photodiode. The spectrometer of the present invention is suitable for use with a wire line formation tester, such as the Baker Atlas Reservation Characterization Instrument to provide supplemental analysis and monitoring of sample clean up. The present invention is also suitable for deployment in a monitoring while drilling environment. The present invention provides a high resolution spectometer which enables quantification of a crude oil's percentage of aromatics, olefins, and saturates to estimate a sample's gas oil ratio (GOR). Gases such as CO2 are also detectable. The percentage of oil-based mud filtrate contamination in a crude oil sample can be estimated with the present invention by using a suitable training set and chemometrics, a neural network, or other type of correlation method.

An image pickup apparatus has a construction in which a diffraction element is provided in an observation optical system. Zero-order light that is transmitted straight through the diffraction element and one of the +1st-order diffracted light and the −1st-order diffracted light that is diffracted by the diffraction element are imaged onto an image pickup surface of an image pickup apparatus. The imaging areas of the zero-order light and one of the +1st-order diffracted light and the −1st-order diffracted light that is diffracted by the diffraction element do not overlap on the image pickup surface of the image pickup apparatus. With this construction, a small image pickup apparatus that provides a high-resolution spectral image and a color image of an object can be obtained.

A method and apparatus for improving spectral resolution of an NMR measurement in the presence of an inhomogeneous magnetic field. According to one embodiment, a method producing a high resolution nuclear magnetic resonance (NMR) spectrum for a sample in an inhomogeneous magnetic field may comprise generating a first magnetic pulse and a second magnetic pulse, the first and second magnetic pulses being separated in time by a first time period, during the first time period, generating a gradient pulse, repeating the steps of generating the first and second magnetic pulses and generating the gradient pulse N times for different values of a field strength of the gradient pulse, wherein N is an integer greater than one, after each second magnetic pulse, acquiring a signal from the sample, and producing a reconstructed high resolution NMR spectrum from the acquired signals.

A new method is developed to accelerate high-resolution magnetic resonance spectroscopic imaging (MRSI). The method is built on a low-dimensional subspace model exploiting the partial separability of high-dimensional MRSI signals and uses this subspace model for data acquisition, processing, and image reconstruction. Specifically for two and three dimensional MRSI with one spectral dimension, this method sparsely samples the corresponding (k,t)-space in two complementary data sets, one with dense temporal sampling and high signal-to-noise ratio but limited k-space coverage and the other with sparse temporal sampling but extended k-space coverage. The reconstruction is then done by estimating a set of temporal/spectral basis functions and the corresponding spatial coefficients from these two data sets. The proposed subspace model can be further extended to incorporate multiple signal components for nuisance signal removal in ¹H-MRSI and more generalized reconstruction methods. The resulting imaging technique can be used for high-resolution MRSI of different nuclei. It will be useful for high-resolution metabolic imaging with many exciting applications.

The invention discloses a high-spectrum-resolution total atmospheric spectral transmittance measuring method. The method includes: using a target tracking device for acquiring sunlight or starlight penetrating the atmosphere as signal light, taking a high-coherence narrow linewidth laser as local oscillation laser, subjecting the signal light penetrating the atmosphere and the local oscillation laser to optical mixing in a heterodyne detector prior to passing through an intermediate-frequency filter and a square-law detector, sending to a band-pass filter to remove noise, enabling a computer to collect for obtaining a heterodyne signal generated by combination of the signal light penetrating the atmosphere and the local oscillation laser, and processing the heterodyne signal to obtain a high-resolution spectrum of weak signal light penetrating the atmosphere. The high-spectrum-resolution total atmospheric spectral transmittance measuring method is used for real-time measurement of total atmospheric spectral transmittance and applicable to fields of atmospheric optics, meteorological research, atmospheric pollution monitoring, detection and the like, and quick response and real-time measurement of high-spectrum-resolution total atmospheric spectral transmittance can be realized according to the method.

The invention relates to a secondary acousto-optic tunable filter hyperspectral imaging method and a device, and belongs to the technical field of optical remote sensing imaging. A high-resolution spectral image of a target to be tested can be taken at visible and near infrared wave bands, and the identification and analysis of the feature and characteristics of the target are realized. The invention is characterized in that: the optical imaging technology and a secondary acousto-optic tunable filter part are organically combined, two acousto-optic tunable filters are used as light splitting elements for spectral imaging and are connected in series in an optical structure, and transmission spectra are multiplied; and the resolution of the system is more than four times higher than that of a spectral imaging system of a single acoustic-optic tunable filter (AOTF). The secondary acousto-optic tunable filter hyperspectral imaging technology and the device have the advantages of high spectral resolution, small size, light weight, quick spectral scanning speed, wide tuning range and the like, and can be widely applied to the fields of remote sensing science, agricultural census, geographic information and the like.

The invention discloses a prism and grating cascading dispersion two-channel and high-resolution spectrum imaging system, belongs to the field of aerospace optics, and solves the problem that the high resolution and the broadband spectrum of a conventional single dispersion spectrum imaging system cannot be detected simultaneously. A broadband light beam going out of an entrance slit of the system is sequentially subjected to collimation by a first collimating mirror and pre-dispersion by a dispersion prism and is focused to a color separation film by a focusing reflecting mirror in a wavelength dividing manner; the color separation film performs transmission on a light beam c with a short wavelength and reflects a light beam d with a long wavelength; the transmission light beam is imaged on a focal plane of a first detector by a first focusing lens group in a wavelength dividing manner after sequentially subjected to folding by a plane turning mirror and a first turning prism, collimation by a second collimating mirror and secondary dispersion of a first plane grating; and the reflection light beam is imaged on a focal plane of a second detector by a second focusing lens group in a wavelength dividing manner after sequentially subjected to folding by a second turning prism, collimation by a third collimating mirror and secondary dispersion of a second plane grating. According to the prism and grating cascading dispersion two-channel and high-resolution spectrum imaging system, the broadband and high spectral resolution are simultaneously detected, the spectral resolution is improved.

A wide viewing field and high-definition imaging structure of frayed end imaging spectrograph, which comprises wide viewing field image-forming lens, several narrow slits, spectrometer, which comprises collimating mirror, optical grating and collective lens), and plate array light-sensitive detector. Optic axis of spectrometer is parallel with imaging lens optic axis. Light splitting is exerted on different viewing narrow slits of image lens focal surface to paste-up a wide viewing field and high-definition imaging spectrum system. According to actual requirement, length and sum of narrow slit, focus of imaging lens and the size of detecting element can be chosen to produce imaging spectrograph of different imaging viewing fields and distinguishabilities.

The invention provides a dayglow temperature photometer and a method thereof for detecting airglow spectrum intensity and temperature. An echelon grating and a narrow-band interference filter equipped with a micro-angle stepping motor are organically combined to serve as a core device of the dayglow temperature photometer, the high spectral resolution is obtained, the range of spectrum detection is broaden by rotating narrow-band filter, and luminous intensity and temperature of dayglows in an upper atmosphere are detected simultaneously by utilizing a high-resolution spectroscopic method and a rotational spectral-line temperature-measuring method. The dayglow temperature photometer comprises four portions including a light guide system, a telescopic system, a light splitting system and an imaging system which are sequentially arranged.