53 results about "Fluorescence lifetime measurement" patented technology

The invention provides a transient fluorescence lifetime measurement method based on single photon counting, which includes the following steps that: 1) a sample is irradiated by pulse light with high recurrence frequency to excite fluorescence; 2) the fluorescence lifetime of the sample is induced to have transient changes according to a certain period; 3) the fluorescence photons of the sample are detected and the corresponding high-speed digital pulse signals which represent the single photon signals are outputted; 4) the macro times of the photons are divided into different time zones, the photons are allocated to different groups according to the macro time and the groups correspond to the time zones of the macro time of the photons; and 5) time-relevant single photon counting is conducted on the photons in each macro time zone according to the high-speed digital pulse signals so as to get a fluorescence decay curve of the fluorescence photons in the macro time zone relative to time. In such way, the fluorescence decay curves in different macro time zones can be obtained. The invention further provides a corresponding transient fluorescence lifetime measurement system. The transient fluorescence lifetime measurement method and system are capable of recording the transient fluorescence decay dynamic curves of the nanosecond time sequence.

The invention relates to a tester of fluorescence life time, based on digit processing chip, wherein it uses photoelectric detector to receive fluorescence signal; via signal amplification and A/D conversion, sends signal into digit processing chip, to be treated with quick method of Fourier transformation, to obtain the amplitude angle relative to the frequency one; and uses formula to calculate the fluorescence life time in the processing chip; then outputs or displays the tested life time, or uses it as reference signal to output to other parameters (temperature, etc); then uses asymmetry receiver/sender to output the lift time and other parameters into computer. The invention has high speed, high accuracy, low cost and small volume, while it will not be affected by local noise.

This invention provides a method for screening large numbers of individual cells or colonies of cells using scanning microscopy coupled with fluorescence lifetime measurement and analysis, using time-correlated single photon counting. This invention further provides an automated method for selecting cells that exhibit desired characteristics. The method uses the scanning microscope system to focus a laser beam onto a surface upon which cells are immobilized on the timescale of the procedure. The cells that are illuminated in this way are killed or their growth is inhibited. The focused laser beam is scanned across the surface and turned on and off during the scanning process such that only non-irradiated cells survive, resulting in a patterned cell growth This invention further provides a computer-controlled projection device, such as a micro-mirror array or a liquid crystal display system, which is sued to project an image onto the cells.

The invention is applicable to the technical field of photoelectric detection, and provides a measuring method and a measuring device of fluorescence lifetime. The measuring method comprises the following steps: firstly, using each row of a preset measurement matrix as a sampling mode, using a non-zero value position in each sampling mode as a sparse signal channel for time gate controlled delayedsampling, performing delayed sampling on a sample in each sampling mode, accumulating the number of photons in the sparse signal channel in the current sampling mode to obtain a compressed sensing measurement value, and repeating each sampling mode to obtain a series of compressed sensing measurement values; then, by virtue of the compressed sensing measurement values and through combination of the measurement matrix, solving an equation under an l1 norm optimization algorithm to obtain a sparse coefficient; finally, acting on the sparse coefficient through known reverse sparse matrix transformation, and performing signal reconstruction to obtain a fluorescence lifetime attenuation curve so as to achieve fluorescence lifetime measurement. By the measuring method provided by the invention,the measurement speed of the fluorescence lifetime is increased.

The invention relates to a high frequency modulation light source used for measuring nanosecond magnitude fluorescence life. Wavelength of the light source can be changed from 940nm to 380nm, can be modulated by high frequency periodic signals from 10MHz to 50MHz, and can detect drive signals of the light source. The invention has the advantages of simple structure, convenient manufacture, small volume, and capable of putting the light source into a sample chamber of a fluorescence spectrometer. A general simple type crystal oscillator is adopted to provide high frequency square wave voltage with temperature stability magnitude from minus or plus 10ppm /0 to minus or plus 50 DEG C for being taken as high frequency modulation signals, the high frequency square wave voltage is supplied to a base electrode of a triode to control electric current of a collecting electrode of the triode, and a light emitting diode is driven to shine. Fluctuation contrast ratio of outputted light intensity excels 0.5, and a buffer amplifier detects drive voltage of the light emitting diode, for providing an improved fluorescence life measurement for improved phase modulation method with stable reference signals.

A fluorescence component that passes through a region of a detection medium where a change in refractive index has been induced through a nonlinear optical effect produced in the detection medium by a gate pulse is observed as a fluorescence image by utilizing a change in polarization state. By observing the change in position of the fluorescence image while correlating with the change over time in the fluorescence, a fluorescence lifetime measuring apparatus is realized with which the change over time in the fluorescence, in particular the fluorescence lifetime, can be measured efficiently with high temporal resolution.

The invention relates to a temperature measurement system based on YAG: Dy fluorescence lifetime measurement as well as a test method and application thereof. The temperature measurement system comprises a signal transmitter, a UV-LED (Ultraviolet-Light Emitting Diode) ultraviolet light source electrically connected with the signal transmitter, a temperature measurement probe and a temperature signal processing unit used with the temperature measurement probe, wherein the temperature signal processing unit comprises a filter, a photomultiplier detector, as well as a resistor box and an oscilloscope electrically connected with the photomultiplier detector in sequence; the surface of the temperature measurement probe is coated with a YAG: Dy fluorescence layer, and the temperature measurement probe is connected with the UV-LED ultraviolet light source and the filter by optical fibers respectively; and the temperature measurement system is used for measuring the temperature of an aero-engine or a ground gas turbine in a working state. Compared with the prior art, the temperature measurement system has the characteristics of high measurement temperature (1080-1700 DEG C) and high temperature accuracy, adapts to the temperature measurement under different environments by changing the shape of the temperature measurement probe, does not influence the temperature field, and is high in temperature precision and wide in application range.

The invention belongs to the technical field of chemical substance detection and relates to a differential confocal discrete fluorescence spectrum and fluorescence lifetime detection method and device. The basic thought is that a differential confocal object surface positioning technology with a precision axial resolution ratio and a discrete fluorescence spectrum and fluorescence lifetime measurement technology are fused; high-precision measurement of a three-dimensional shape of the surface of a sample to be detected is solved by utilizing a differential confocal technology; meanwhile, high-sensitivity detection of a fluorescence spectrum and fluorescence lifetime of each point on the surface of the sample to be detected is solved by utilizing the discrete fluorescence spectrum and fluorescence lifetime measurement technology, so that three-dimensional high-resolution space substance component distribution information is obtained. According to the differential confocal discrete fluorescence spectrum and fluorescence lifetime detection method and device, a differential confocal measurement technology and a fluorescence substance component detection technology are fused for the first time; a fluorescence imaging system has the same transverse resolution ratio on each position of the surface of the sample to be detected; finally, measured fluorescence spectrum distribution accurately corresponds to the three-dimensional shape. The technology provided by the invention has a wide application prospect in the fields of biological science, medical science, material science and clinical medical diagnosis.

The invention relates to a YSZ: Re fluorescence lifetime measurement-based temperature measurement system, a test method thereof and the application thereof. The temperature measurement system comprises a signal transmitter, a UV-LED ultraviolet light source electrically connected with the signal transmitter, a temperature measurement probe and a temperature signal processing unit matched with the temperature measurement probe. The temperature signal processing unit comprises an optical filter, a photomultiplier tube detector, a resistance box and an oscilloscope, wherein the resistance box and the oscilloscope are sequentially and electrically connected with the photomultiplier tube detector. The surface of the temperature measurement probe is sprayed with a YSZ: Re fluorescent layer and is respectively connected with the UV-LED ultraviolet light source and the optical filter through optical fibers. The temperature measurement system is used for measuring the temperature of an aircraft engine or a ground gas turbine temperature in the working state. Compared with the prior art, the measurement temperature can be high up to 500-1200 DEG C and the temperature accuracy is high. Through changing the shape of the temperature measurement probe, the temperature measurement probe can be applied to the temperature measurement under different environments. Meanwhile, the temperature field is not affected. The advantages of high temperature accuracy and wide application range are realized.

The invention discloses a Raman-fluorescence lifetime spectrometer based on a single phototn avalanche diode (SPAD) array sensor, a picosecond-level time gating circuit, a high-precision time-to-digital converter (TDC) and a high-speed fluorescence lifetime algorithm. An SPAD array is used as a Raman spectrum and fluorescence signal detector, and the picosecond-level time gating circuit is used for filtering noise to improve the signal-to-noise ratio and the detection efficiency; and the time domain information of the Raman spectrum and a fluorescence attenuation curve is recorded through TDC,and a fluorescence lifetime algorithm is combined to rapidly calculate the fluorescence lifetime. A real and pure Raman signal is obtained by utilizing a fluorescence background inhibition algorithm,so that the detection capability and the detection efficiency of Raman spectrum and fluorescence lifetime are improved. According to the invention, Raman spectrum, fluorescence spectrum and fluorescence lifetime measurement and calculation can be achieved at the same time by using one set of system, and Raman spectrum, fluorescence spectrum and fluorescence lifetime measurement and calculation can be obtained respectively, so that the Raman-fluorescence lifetime spectrometer has obvious technical advantages compared with a traditional method.

The invention relates to a rare earth europium fluorescent chelating agent and a preparation method thereof. The rare earth europium fluorescent chelating agent is 4,4'-dibromo-6,6'-bis(N,N-bis(ethoxycarbonyl methyl)aminomethyl)-2,2'-bipyridine; and the rare earth europium fluorescent chelating agent can form 4,4'-dibromo-6,6'-bis(N,N-bis(ethoxycarbonyl methyl)aminomethyl)-2,2'-bipyridine-Eu3+fluorescent chelating agent having fluorescence characteristics of europium ions and fluorescence lifetime with trivalent europium ions by hydrolysis. Detection is carried out on a fluorescence time-resolved spectroscopy and a fluorescence lifetime measurement instrument: a new fluorescence spectrum with the characteristic peak of the europium ions is formed at 615nm under the excitation of a light source of 337nm, and the fluorescence lifetime thereof is about 610 microseconds.

A fluorescence lifetime measurement apparatus includes a first controller controlling a total gate length and a second controller controlling a start gate length of a plurality of gate lengths into which the total gate length is divided. The start gate length is a time window whose start time is when measurement of the number of fluorescence photons of a specimen starts. The apparatus also includes a measurer measuring the number of fluorescence photons for each of the gate lengths; a processor calculating a fluorescence lifetime the specimen based on the start gate length and the number of fluorescence photons; and a third controller causing, when the fluorescence lifetime does not satisfy a predetermined condition, the first and second controllers to change the start gate length and the total gate length.

The invention discloses a device and method for measuring the service life of mono-dispersion up-conversion nanometer fluorescent particles. The device comprises a two-photon microscope assembly and an electrical control assembly. The two-photon microscope assembly comprises a laser device, a plurality of optical frames, a Pockels cell, a two-dimensional galvanometer scanning module and a photomultiplier. The laser device emits light beams, the light beams pass through the optical frames and the Pockels cell and enter the two-dimensional galvanometer scanning module to conduct two-dimensional scanning on a sample, and fluorescent signals generated when the sample is excited are collected by the photomultiplier. The electrical control assembly is used for controlling the two-photon microscope assembly to work. By means of the device and method, fluorescent imaging and fluorescent service life measurement are conducted on a UCNPs material in a mono-dispersion state, and data measured through a time-domain method is visual and easy and convenient to process.

The invention belongs to the technical field of chemical substance detection. By adoption of design of spectral pupil, the interference on the result by autofluorescence of an optical component in anexcitation light path can be effectively shielded and the signal to noise ratio of the system is increased. In addition, a confocal object surface positioning technology, a discrete fluorescence spectrum and a fluorescence lifetime measuring technology are fused; and high-precision measurement of three-dimensional shape of a to-be-tested sample is realized by utilizing a confocal technology, and high-sensitivity detection of the fluorescence spectrum and fluorescence lifetime of each point of the surface of the to-be-tested sample is realized by utilizing a discrete fluorescence spectrum and fluorescence lifetime detection technology, so that three-dimensional high-resolution spatial material component distribution information is acquired. Furthermore, in the process of measuring the fluorescence information of the surface of the sample, various different discrete fluorescence detection means are used and comprise fluorescence spectrum detection and fluorescence lifetime detection. Wide application prospect in the fields of biology, medicine, material science and clinical medicine diagnosis is achieved.

The invention relates to a time resolution fluorescence spectrometer, in particular to an integral femtosecond time resolution fluorescence lifetime measurement spectrograph. The integral femtosecondtime resolution fluorescence lifetime measurement spectrograph comprises a detection and pump laser light path system, a sample fluorescence collection system and a spectrum detection system. The spectrograph excites a sample through a beam of femtosecond laser, and the other femtosecond laser enables the excited sample to do stimulated radiation; the spectrum detection system integrates collectedsample fluorescence to measure the fluorescence lifetime. The time resolution fluorescence spectrometer improves the detection sensitivity of fluorescence lifetime measurement.

The invention discloses a measurement module. The module uses a motor to drive an excited sample to rotate in space, so that illuminating signals with different delay times are spatially separated, and then the micro space is enlarged by a lens, a specific spatial domain is also selected for observation, and the time-resolved detection can be achieved. Through the combined use of the module and animage sensor, the lifetime of the excited state can be measured; and through the combined use of the module and a spectrograph, the time-resolved spectrum detection can be implemented. According to the resolution of optical imaging and the rotating speed of an existing motor, the time resolution of the device can reach a nanosecond level, and most fluorescence lifetime measurements can be satisfied. The method can measure the lifetime of the excited state by using a steady-state light source with arbitrary wavelength, does not need expensive pulsed light sources and detectors, does not need aphase-locked control operation, and has a lower cost.

A fluorescence lifetime measuring apparatus according to an embodiment of the present invention includes: an irradiation light generator configured to generate irradiation light; a fluorescence photon detector configured to irradiate at least one or more samples, containing fluorescent molecules, with the irradiation light and collect a fluorescence photon generated by the irradiation; a converter configured to amplify the fluorescence photon and convert the amplified fluorescence photon into a fluorescence signal; and a measurer configured to analyze data of a function of the fluorescence signal by using a function obtained by multiplying a value, which is obtained by integrating the function of the fluorescence signal, by a simulation function.

The invention discloses a transmission electron microscope sample rod system with ultrafast time-resolved spectrum capability, which at least comprises an optical system consisting of a sample rod provided with an optical fiber, an ultrafast laser, a dispersion compensation element, a spectrograph, a time-dependent single photon counter and the like, and an mechanical system composed of a piezoelectric ceramic tube, a differential micrometer head, a three-dimensional displacement table and the like. The optical system and the mechanical system are used for achieving in-situ focusing of pulsedlight and three-dimensional scanning of focusing light spots in a transmission electron microscope, signals such as fluorescence and the like are excited and collected through the sample rod providedwith the optical fiber, and finally the fluorescence spectrum and the fluorescence lifetime are measured through the spectrograph and the time-dependent single-photon counter. The transmission electron microscope sample rod system with the ultrafast time-resolved spectrum capability is realized and is used for introducing focused femtosecond pulse light into a transmission electron microscope to perform fluorescence spectrum characterization and fluorescence lifetime measurement, so that ultrafast spectroscopy measurement is completed in the transmission electron microscope.

The invention belongs to the technical field of chemical substance detection. By adoption of design of spectral pupil, the interference on the result by autofluorescence of an optical component in anexcitation light path can be effectively shielded and the signal to noise ratio of the system is increased. In addition, a differential confocal object surface positioning technology, a discrete fluorescence spectrum and a fluorescence lifetime measuring technology are fused; and high-precision measurement of three-dimensional shape of a to-be-tested sample is realized by utilizing a differentialconfocal technology, and high-sensitivity detection of the fluorescence spectrum and fluorescence lifetime of each point of the surface of the to-be-tested sample is realized by utilizing a discrete fluorescence spectrum and fluorescence lifetime detection technology, so that three-dimensional high-resolution spatial material component distribution information is acquired. Furthermore, in the process of measuring the fluorescence information of the surface of the sample, various different discrete fluorescence detection means are used, and a user can select to use ether fluorescence spectrum detection or fluorescence lifetime detection according to the chemical characteristic of the to-be-tested substance. Wide application prospect in the fields of biology, medicine, material science and clinical medicine diagnosis is achieved.

The invention discloses a fluorescence lifetime imaging device based on a spectrum division technology. The fluorescence lifetime imaging device comprises a light source and a microscope objective forconverging exciting light emitted by the light source and exciting a sample to emit fluorescence, and the device is provided with a spectrum division module used for carrying out spectrum division onfluorescence collected by the microscope objective, a detection module used for receiving fluorescent molecules of different wave bands after spectrum division, and a counting module used for carrying out photon counting on the fluorescent molecules and calculating fluorescence lifetime information. Meanwhile, the invention further discloses a fluorescence lifetime imaging method based on the spectrum division technology. According to the invention, a spectrum division technology is introduced, and wide-band fluorescence signals are decomposed to different channels through the spectrum division module and are received by different detectors, so that the influence of dead time of a single detector on fluorescence lifetime measurement in a traditional method is greatly relieved, and the problem of photon accumulation effect of fluorescence lifetime measurement is relieved; and the effective detection efficiency of photons is improved, and the life imaging speed is increased.

The invention discloses a method and a system for measuring fluorescence lifetime. The method comprises the following steps of irradiating a sample by exciting light, and enabling a photomultiplier to receive the fluorescence produced by the sample, wherein a modulation signal of the exciting light is a cosine signal with the frequency of fE; modulating the gain voltage of the photomultiplier by a square wave signal X(t) with frequency of fH0; after the fluorescence produced by the sample passes through the photomultiplier, enabling a fluorescence screen to receive a first image; enabling a photoelectric detector to collect the first image, so as to obtain a second image; according to the second image, calculating the fluorescence lifetime of the fluorescence produced by the sample. Compared with the prior art, the method and the system for measuring the fluorescence lifetime have the advantages that the fluorescence lifetime is measured through heterodyning high-order harmonic component modulation; the gain voltage of the photomultiplier is modulated by the low-frequency square wave signal, and the technical requirement on an image intensifier is decreased.