69results about How to "High resolution measurement" patented technology

An image-based technique that measures the orientation of fibers in a moving web of nonwoven material includes the steps of: (a) illuminating essentially simultaneously at least four light spots on one side of the web with at least four plane-polarized incident substantially perpendicular light beams having different polarization characteristics, (b) measuring the dispersion of the excident light spots on the opposite side of the web along at least one linear section which is at a known angle relative to the plane of polarization of the corresponding plane-polarized incident light beam, wherein at least one such linear section lies substantially across the center of the transmitted excident light spot and extends substantially across the width of the transmitted excident light spot, (c) calculating variations in the dispersion of the transmitted excident light spot for the at least four plane-polarized light beams; and (d) estimating the fiber orientation from the variations.

Examples of methods and apparatus for an accurate measurement of the anterior surface of the eye including the corneal and scleral regions are disclosed. The measurements provide a three-dimensional map of the surface which can be used for a variety of ophthalmic and optometric applications from astigmatism and keratoconus diagnostics to scleral lens fitting.

A method of operating a scanning probe microscope (SPM) includes scanning a sample as a probe of the SPM interacts with a sample, and collecting sample surface data in response to the scanning step. The method identifies a feature of the sample from the sample surface data and automatically performs a zoom-in scan of the feature based on the identifying step. The method operates to quickly identify and confirm the location of features of interest, such as nano-asperities, so as to facilitate performing a directed high resolution image of the feature.

The invention designs a quantitative measurement method and device for a transient combustion field and belongs to the technical field of combustion diagnosis. The device comprises a clock synchronization and delay triggering module, a tunable laser generation module, an optical fiber beam splitter, a lens group, a photoelectric detector array, a high-speed multi-path data acquisition module, a high-energy pulse laser generation module, an area array photoelectric detector, a control and calculation module and the like. The optical parameters of a laser-induced fluorescence test system are calibrated by utilizing a steady-state combustion field; the calibrated device is used for measuring the same section of the transient combustion field; and low-resolution temperature distribution obtained by laser absorption spectrum tomography is substituted into an established laser-induced fluorescence calculation model, so that high-resolution temperature and the concentration distribution of measured groups and molecules can be obtained. According to the method and device of the invention, laser-induced fluorescence and a laser absorption spectrum are fused, so that the method and device are of great application value for the monitoring and diagnosis of a combustion field.

The invention discloses a distributed strain and temperature optical fiber sensor based on brillouin scattering. The sensor comprises a light source, an electro-optical modulator, a pulse signal source, a first erbium-doped optical fiber amplifier, a second erbium-doped optical fiber amplifier, a circulator, a first optical coupler, a second optical coupler, double balance detectors, a signal processing system and a sensing optical fiber. The sensing optical fiber comprises a long period optical fiber grating and is an all-solid photonic crystal band gap optical fiber. Output light of the light source is divided into two paths, wherein one path of the output light is modulated to be detection pulse light by means of the electro-optical modulator, is amplified through the erbium-doped optical fiber amplifiers and is input into the sensing optical fiber through the circulator. The sensor can simultaneously obtain temperature and strain with high resolution through a single measurement, and can well solve the problem of cross sensitivity existing in measurement of a brillouin sensor.

A method and device for measuring an evoked neural response comprising a sensor (25) for obtaining a sensed signal representing the evoked neural response, a high gain amplifier (30) having a signal input (31) for receiving the sensed signal and having a reference input (32), and means for altering or setting a reference voltage at the reference input (32) to prevent the amplifier (30) saturating with variations of the sensed signal.

The invention discloses a broadband chaotic laser-based distributed optical fiber dynamic strain sensing device, which comprises a broadband chaotic laser source (1), a 1*2 optical fiber coupler (2),a first polarization controller (3), a high-speed electro-optic modulator (4), a programmable optical delay generator (5), a first optical amplifier (6), an optical polarizer (7), an optical isolator(8), a sensing optical fiber (9), an optical circulator (10), a second optical amplifier (11), a semiconductor optical amplifier (12), a second polarization controller (13), a pulse signal generator (14), a broadband microwave signal source (15), a high speed data acquisition and analysis system (16), a photoelectric detector (17), and a tunable optical filter (18). The pulse signal generator is used to generate high speed pulse signals, synchronous control on the broadband microwave signal source, the semiconductor optical amplifier and the high speed data acquisition and analysis system is realized, and the measurement accuracy and the real-time performance of the sensing system are ensured.

The invention provides a micro-pressure sensor and a manufacturing and detecting method thereof. The sensor mainly comprises an upper thin plate, a middle thin plate and a base from top to bottom. An upper cavity is formed by the middle thin plate, the upper thin plate and an upper strut, and the upper surface of the middle thin plate or the lower surface of the upper thin plate is provided with an upper insulating layer. A lower cavity is formed by the middle thin plate, the base and a lower strut, and the lower surface of the middle thin plate or the upper surface of the base are provided with a lower insulating layer. The upper thin plate serves as a sensor pressure sensitive element, the middle thin plate serves as a resonant element of the sensor, and the upper thin plate, the middle thin plate and the base serve as the upper electrode, the middle electrode and the lower electrode of the sensor. During pressure measuring, the electrostatic force borne by the middle thin plate changes due to the deformation, caused by pressure, of the upper thin plate, the resonant frequency of the middle thin plate changes, and pressure measuring can be achieved through the relation between the resonant frequency and the pressure change. The sensitivity of the sensor can be improved, and high-sensitivity detecting for micro-pressure is achieved conveniently.

The invention discloses a wide-range optical fiber vacuum sensor with multiple steps and a manufacturing method of the wide-range optical fiber vacuum sensor with the multiple steps. The wide-range optical fiber vacuum sensor comprises a sensor head, a sensor body, a transmission optical fiber, a supporting structure of the sensor and an accommodating structure of the transmission optical fiber. The sensor head is a stepped optical fiber vacuum sensor head and provided with a dual-layer structure with SiO2 oxide layer steps. The first layer structure is a monocrystalline silicon wafer, the second layer structure is a Pyrex glass wafer, a two-level stepped round shallow pit array is arranged on the front surface of the Pyres glass wafer, the Pyres glass wafer is divided into single sensor units, wherein the surfaces of the sensor units are squares or other polygons, and the round shallow pit array comprises a first round shallow pit step and a second round shallow pit step. The wide-range optical fiber vacuum sensor achieves high precision pressure measurement in a vacuum region, can survive in a constant pressure range without other packaging measures, can be used for high precision measurement in the constant pressure range, can effectively expand the high precision pressure measurement range of the sensor, and is convenient to manufacture in a massive mode.

An SPM cantilever of the present invention including: a support portion (1) fabricated by processing a single crystal silicon wafer; a lever portion (2) formed in a manner extended from the support portion; a probe (3) disposed at a free end side of the lever portion; a coating of graphite film (5) covering all over the side on which the probe is formed and the entire probe; and a piece of thin line (6) consisting of a carbon nanofiber (CNF) or carbon nanotube (CNT) or graphite nanofiber (GNF) grown/formed from the graphite film at a probe terminal end portion (3a).

The invention discloses an atmospheric NO2 detection system based on an electrochemical transducer, and belongs to the field of atmospheric environmental monitoring. The atmospheric NO2 detection system comprises a sensor module, a data acquisition and processing module, and a man-machine interaction visualized module; the sensor module comprises a NO2 four-electrode electrochemical transducer and a temperature and humidity sensor; the data acquisition and processing module comprises a low noise signal conditioning circuit and a DSP main control unit; the man-machine interaction visualized module comprises a LabVIEW 2015 platform and a sound-light alarming module. Compared with a traditional NO2 detection system, the atmospheric NO2 detection system based on the electrochemical transducer is more concise, small in size and convenient to carry, and is capable of achieving a high-accuracy measurement of NO2 with low concentration of a ppb order in the atmosphere, accurately eliminating interference, caused by zero wander of the electrochemical transducer and ambient temperature and humidity change, on a detection result of the NO2 when the concentration of NO2 is low, and improving reliability of the detection result; meanwhile, the atmospheric NO2 detection system based on the electrochemical transducer is high in stability, high in sensitivity, high in linearity and good in human-computer interaction interface, and has a wide application prospect.

In an external force detecting device including a support section and an action section disposed inside the support section, three optical displacement sensors are provided at an equiangular distance of 120 degrees about the rotational symmetry axis of the support section and each include a light source disposed at either the support section or the action section, and a light receiving element disposed at one section of the support section and the action section, the one section not provided with the light source, and the action section is located between the light source and the light receiving element. The external force detecting device described above enables an easy mounting of constituent members and a high resolution measurement, even when the diameter of the device is reduced.

There is provided a superconducting radiometry apparatus capable of performing, while sample-measuring, an energy correction in regard to a fluctuation of a peak value of an output signal, which is due to a radiation heat and a magnetic field from an outside. The superconducting radiometry apparatus is constituted by comprising a micro-calorie meter detecting an energy of a radiant ray as a temperature change, a signal detection mechanism for detecting a displacement of an electric current flowing to the micro-calorie meter, a shunt resistance which is connected in parallel to the micro-calorie meter and whose resistance value is smaller than the micro-calorie meter, a bias electric source connected to the micro-calorie meter and the shunt resistance and applying a constant voltage, a heat addition device adding a constant and already-known heat quantity to the micro-calorie meter, a peak value monitor measuring a peak value corresponding to an added heat quantity within an output signal from the signal detection mechanism while synchronizing with a heat quantity addition from the heat addition device, and an energy correction device correcting, on the basis of an output from the peak value monitor, so as to become a peak value corresponding to the heat quantity from the heat addition device.

Temperature is determined by measuring the time it takes to charge a capacitor with a resistive temperature sensor. A clock, time counter, a voltage comparator and voltage reference are used in determining a course time measurement. The time measurement resolution is enhanced with the addition of a constant current source charging another timing capacitor within a single clock pulse time to provide a fine time measurement.

An extensometer measures and monitors changes in complex loads on a structure. The extensometer comprises opposed cantilever beams fixed in “mirrored” position and aligned with the structure. Each beam has a fixed end and a free end. The fixed end of the cantilever beam is attached to the structure being monitored. The free ends are attached to each other through a compliant, linearly elastic sensing element that is distorted by rigid-body motions of the cantilever beams relative to their attachments to the structure. The sensing element is capable of first order isolation of signals from discrete components of deflections of the structure in proportional response to the strains or stresses on the structure.

The invention provides a Brillouin time domain analysis system and method based on a multi-core optical fiber. According to the analysis system and method, a pulsed chaotic laser signal source is setto generate a chaotic optical signal with good characteristics, high-resolution measurement irrelevant to distance can be realized, and position information of a maintenance fault point of the opticalfiber can be accurately reflected. In order to eliminate the problem that Brillouin frequency shifts are sensitive to bending in eccentric fiber cores, according to the embodiment, the Brillouin frequency shifts of two symmetrical outer cores are averaged first, so that the effect of bending on the Brillouin frequency shifts is eliminated; and then the averaged Brillouin frequency shifts and dataof the middle core are combined to solve a coefficient matrix, so that decoupling of temperature and stress is realized.

A device for measuring three dimensional shape includes a first height data acquisition unit for acquiring a height data specified from measurement values according to a multiplicity of light patterns related to an entirely irradiated region irradiated by all of the multiplicity of light patterns, and for using an acquired specified height data as a height data for the entirely irradiated region; a supplemental data acquisition unit for acquiring, based on the height data for the entirely irradiated region, a supplemental data relating to a partially irradiated region that is irradiated by only part of the multiplicity of light patterns; and a second height acquisition unit for specifying a fringe order of the measurement values for the partially irradiated region based on the supplemental data, and for acquiring as height data for the partially irradiated region a height data corresponding to the measurement values of the specified fringe order.

The invention discloses a cross-scale micro-nano structure three-dimensional measurement device and a measurement method. The device is characterized by comprising an atomic force probe scanning microscope assembly, an objective lens turntable, a white light interference system, a nanoscale vertical micro-displacement platform, a laser interference displacement metering system I, a measurement andcontrol system, a laser interference displacement metering system II, a sample piece, a two-dimensional piezoelectric ceramic scanning platform, a two-dimensional electric scanning platform and a laser interference displacement metering system III. According to the invention, by rotating the objective lens turntable, the measuring device is switched between a white light interference measuring mode and an atomic force probe scanning measuring mode, wherein the white light interference measuring mode is mainly used for large-scale measurement of a micron-scale structure, and the atomic force probe scanning measuring mode is used for carrying out horizontal high-resolution measurement on the nanoscale feature region, so that large-range and high-resolution measurement on the surface of thecross-scale micro-nano structure is achieved, and measurement of the cross-scale (micron scale, submicron scale and below scale) structure can be achieved in one set of system.