46results about How to "High time resolution" patented technology

The invention discloses a rice yield remote sensing estimation method based on MODIS data, which comprises: 1) acquiring the MODIS09 remote sensing data in the growth process of the rice in the region to be monitored, and calculating an vegetation index EVI and a water index LSWI; 2) extracting a rice pixel based on the relation between the water index LSW1 and the vegetation index EVI; 3) acquiring the vegetation index EVI corresponding to the rice in different stages; 4) calculating the average of the vegetation indexes EVIs of different set administrative regions in different stages to acquire the average EVI of the set administrative regions; 5) establishing a statistical model for the average EVI of the set administrative regions and the rice yield; and 6) estimating the rice yields of the set administrative regions using the vegetation index EVI in the growth period of rice in the year to be estimated, and calculating the rice yield of the region to be monitored. The temporal resolution, the spatial resolution and the estimation precision of the invention are relatively high, and the invention is applicable to monitoring rice yield in a large scale.

The invention relates to a large-area X-ray pulse detection device based on microchannel plate split joint. The large-area X-ray pulse detection device comprises an X-ray photoelectric cathode, a first insulating layer, a microchannel plate (MCP) input electrode press ring, a second insulating layer, an MCP input electrode, a first MCP layer, an intermediate electrode, a second MCP layer, a third insulating layer, an MCP output electrode, a fourth insulating layer, and an anode which are sequentially stacked up, wherein the first MCP layer and the second MCP layer are both large-area MCP detectors, and each MCP detector comprises a detector body, a split-joint framework and a processing circuit. The large-area X-ray pulse detection device resolves the technical problems that an existing MCP detector is adopted to detect the X-ray pulse, extremely long observation time is needed, and detection efficiency of the whole system is low, a detection method and a device which are high in detection efficiency are provided for an X-ray pulsar navigation system, photon measurement information with high time resolution and high time accuracy is provided for X-ray pulsar navigation, and guarantee is provided for high precision of navigation positioning.

The invention discloses a compact ultra short pulse laser remote ranging system and a ranging method thereof. The system comprises a laser source, a first beam expanding module, a second beam expanding module, a beam splitter, a transmitting and receiving module, a reflector, a filter module, a focusing lens, and a photodetector, wherein the laser source is an ultra short pulse laser transmitting laser beams, and the width of the outputted laser pulse is picosecond to subpicosecond. The system whose transmitting light path and receiving light path are coaxial is adopted, one reflector is adopted to complete sampling of main wave pulse signals; through changing coating reflectivity of the reflector, the size of an incident main wave signal is adjusted, and over strong main wave pulse signals can be prevented from damaging the photodetector; and the laser ranging system is long in ranging, high in ranging precision, simple and compact in structure, and low in cost.

The invention relates to a terahertz-driven electronic pulse accelerating femtosecond electron diffraction device which comprises a femtosecond laser, a beam splitter, an ultraviolet laser pulse generator, a terahertz pulse generator, an electron gun, an electron focusing device, a sample room, an imaging device and a camera. After the femtosecond laser emitted by the femtosecond laser passes through the beam splitter, one beam of femtosecond laser enters the ultraviolet laser pulse generator, and the other beam of femtosecond laser enters the terahertz pulse generator through a mirror. An ultraviolet laser pulse and a terahertz pulse received by the electron gun enter the cavity of the electron gun to produce an electronic pulse. The electron focusing device is mounted between the cavity of the electron gun and the sample room. A sample assembly and the imaging device are placed inside the sample room in sequence along the emitting direction of the electronic pulse. The camera is placed at a position, facing the imaging device directly, outside the sample room. The device can run in a reflection or transmission mode, can be used in research of both a reversible process and an irreversible process, and is of high brightness and high spatial-temporal resolution.

The invention belongs to an aerosol measuring technology, in particular to a high time resolution microsampling method and device of atmospheric aerosol. The invention realizes the high time resolution microsampling of aerosol in the atmospheric environment by combining a fine particle microsampling device and a rapid high-sensitivity detection technology, realizes the tracking measurement of time resolution aiming at components harmful to human bodies in fine particles and monitors the pollution of the fine particle aerosol. The rapid high-sensitivity detection technology provided by the invention comprises an aerosol particle size cutting technology, an aerosol particle size selecting technology, a high-sensitivity aerosol detection technology and a computer control technology. By applying the fine particle microsampling device provided by the invention, unequal sampling times and different sampling frequencies can be finally set according to different chemical species in different particle size ranges, such as PM10 and PM2.5 to obtain a sampling quantity reaching a detection limit; the corresponding sampling area is smaller than 1 cm<2>, and the whole machine has the weight less than 10 kg and is portable.

The invention relates to a high time resolution three-dimensional imaging method based on a framing camera. The high time resolution three-dimensional imaging method based on the framing camera includes the following steps: 1), obtaining a two-dimensional image of an object to be tested by utilization of the framing camera; and 2), performing three-dimensional reconstruction on the obtained two-dimensional image of the object to be tested to obtain the three-dimensional visual effect object to be tested. The high time resolution three-dimensional imaging method based on the framing camera is capable of obtaining the three-dimensional image with picosecond (10-12 S) time resolution, and providing a reliable basis for direct improving on laser beam forms in a test process.

An optical receiver, e.g., for an Optical Supervisory Channel (OSC), whose optical front end comprises a polarization-diversity coherent optical receiver configured to receive a conventional intensity-modulated (e.g., OSC) signal. Four quadrature components of the received OSC signal detected by the polarization-diversity coherent optical receiver are sampled at a relatively high sampling rate and are used to calculate the Stokes parameters of the OSC signal. As a result, the Stokes parameters can be updated at the high sampling rate, which can be suitably selected to enable polarization tracking with a relatively high time resolution and/or at relatively high SOP-rotation speeds. The four detected quadrature components are appropriately combined in the receiver DSP to determine the intensity of the received OSC signal, which is then used in a conventional manner to recover the OSC data encoded therein.

The invention belongs to an ultra wide band swept-frequency microwave radiometer based on a frequency doubling technology. The ultra wide band swept-frequency microwave radiometer comprises an arbitrary waveform generator and a wide band VCO (voltage controlled oscillator) source, wherein the arbitrary waveform generator is connected with the input ends of the wide band VCO source, an isolator and a power distributor in sequence; the previous three output ends of the power distributor are connected with the LO input ends of a frequency doubler group and a frequency mixer group; the fourth output end of the power distributor is connected with a detector and an oscilloscope; the input end of a receiving antenna receives a signal radiated from a plasma; the output end of the receiving antenna is connected with RF input ends of a band-stop filter, a waveguide power distribution array and the frequency mixer group in sequence; the IF output end of the frequency mixer group is connected with a bandpass filter, a power amplifier and an analog/digital converter in sequence. The ultra wide band swept-frequency microwave radiometer has the advantages that the measurement of the electronic temperature distribution on the whole section of a longitudinal field under the plasma discharge condition of 1.0-2.5T can be realized, and the measurement frequency range can be 40-220GHz.

The invention discloses a time resolution ptychography and provides a method for providing image data. According to the method, a collected associated diffraction image is utilized to reconstruct relevant information of a region of a target object. The method comprises the following steps: obtaining a target image until enough associated images are collected; utilizing an enhanced ptychography iteration engine (ePIE) to obtain the reconstruction of the target object relative to time average; by taking the target object for reconstructing all time sequences and a probe function as targets, changing initial input; and utilizing the ePIE to finally obtain a result. Compared with the problem that the ptychography and other imaging technologies only can reconstruct the information of the static target object in the prior art, the time resolution ptychography can obtain the reconstruction of time resolution of the target object.

The invention provides a single-pulse laser-induced transient molecular fluorescence spectrum measurement method and system, and the method comprises the steps: employing a femtosecond laser-induced fluorescence emission technology to excite a sample to generate to-be-measured fluorescence, and enabling the fluorescence to be collected in a reverse direction in the propagation direction of excitation light; enabling one linear chirped pulse to interact with a fluorescence signal to be detected in a second-order nonlinear medium to generate a sum frequency optical signal, wherein an intensity recess is formed in the acted chirped pulse, and the chirped pulse with the intensity recess is subjected to time broadening through a time amplification system; detecting the broadened chirped pulse with the recess and the component of the linear chirped pulse by a photoelectric detector with high-speed response together, outputting, recording and measuring two signals by a high-speed oscilloscope, and obtaining a transient molecular fluorescence signal spectrum after time amplification after processing. According to the technology, a molecular fluorescence spectrum excited by a single femtosecond pulse can be rapidly measured, a continuous single-frame fluorescence signal spectrum with high resolution and real-time performance is obtained, and the method is a method for rapidly measuringthe spectrum aiming at an irrepeatable physical process or an irreversible transient process.

The invention relates to a composite photoelectric cathode X-ray detection device, which comprises a support framework, a reflecting layer photoelectric cathode, an MCP (Micro Channel Plate) input electrode, an insulation pad, at least one electron multiplying unit, a polymer film, a metal film, a transmission layer photoelectric cathode and a cathode electrode, wherein the polymer film, the metal film, the transmission layer photoelectric cathode and the cathode electrode are arranged in a support framework in sequence; the cathode electrode is positioned between the transmission layer photoelectric cathode and the inner wall of the support framework; the electron multiplying unit comprises an MCP and an output electrode; the output electrode is fixed on a base of the support framework; the MCP is arranged on the output electrode; the reflecting layer photoelectric cathode is positioned on a layered MCP input surface; the MCP input electrode is positioned between the reflecting layer photoelectric cathode and the inner wall of the support framework, and is fixed on an uppermost layer MCP; and voltage U between the cathode electrode and the MCP input electrode is supplied by an external power supply. According to the composite photoelectric cathode X-ray detection device, the technical problems of extremely long observing time required by the detection of X-ray pulses and low detecting efficiency of an entire system are solved, and the detection efficiency of extremely weak X-ray pulses is increased.

Conventional real-time spectrum analyzers have a degree of technical complexity in the hardware which increases disproportionately as the analysis bandwidth increases for Fourier transformations of the measured sampling values. When using high analysis bandwidths, a detailed resolution is not needed of each analyzed individual frequency on the time plane at the same time; instead, detection of the presence of short pulses can be important as well. For this application, mixing sampling values on the time plane using a variable auxiliary frequency allows the sampling rate to be reduced, in that the bandwidth is maintained but a compression is carried out on the time plane. A very high time resolution which far exceeds the capabilities of conventional real-time spectrum analyzers can additionally be achieved overall for the analysis bandwidth, the time resolution then being computationally assignable to the individual frequencies for signal forms, in particular pulses, which occur in practice.

The invention discloses a scintillator and a scintillator detector including the scintillator. The scintillator with the section approximate to trapezoid is provided with a reflection groove, an opening end of which is positioned at a large end face of the scintillator, and the width of the opening end gradually diminishes from the large end face to a small end face of the scintillator. According to the invention, a reflection face is added by means of the arrangement of the reflection groove, thereby reducing average optical path of lights, enhancing proportion of effective signals and raising detection efficiency of the detector; in addition, optical path difference of lights is reduced, the full width at half maximum (FWHM) and one-tenth height and width of signals are lessened, so time resolution of the detector is enhanced; and the scintilator and the scintillator detector also save material and lower cost.

A micro-scanning space-time resolution measuring system comprises a high-voltage power supply, a gate pulse generator and a micro-scanning image converter tube. The micro-scanning image converter tube comprises a disc-shaped flange, a coaxial connector, a PCB substrate, a fluorescent screen, a gain-free microchannel board, a cathode microstrip line, an external intensifier and a visible light CCD. The micro-scanning space-time resolution measuring system is adopted, the transition time of emergent photoelectrons is short, the spatial resolution superior to 5 microns is achieved, and meanwhile the time resolution of the system can be greatly improved.