30 results about "Photon correlation" patented technology

A source and/or method of generating quantum-correlated and/or entangled photon pairs using parametric fluorescence in a fiber Sagnac loop. The photon pairs are generated in the 1550 nm fiber-optic communication band and detected by a detection system including InGaAs/InP avalanche photodiodes operating in a gated Geiger mode. A generation rate>10³ pairs/s is observed, a rate limited only by available detection electronics. The nonclassical nature of the photon correlations in the pairs is demonstrated. This source, given its spectral properties and robustness, is well suited for use in fiber-optic quantum communication and cryptography networks. The detection system also provides high rate of photon counting with negligible after pulsing and associated high quantum efficiency and also low dark count rate.

The invention relates to a photon correlator based on a field programmable gate array (FPGA), which is used for obtaining scattered light signal autocorrelation function in photon-correlation spectroscopy granulometry technology and is mainly composed of a synchronous reset module, a photon counting module, a correlation algorithm module and a computer interface module, wherein the photon counting module carries out the evenly spaced counting for photon signal period of a photon detector and sends the result to the photon correlation algorithm module to obtain a correlation function; the computer interface module sends the result to the computer. The invention realizes the high-speed photon correlator based on the field programmable gate array (FPGA) and expands the number of channels of the correlator and dynamic range time in a multi-disc FPGA cascading mode.

The invention relates to a high concentration superfine particle measurement device and method based on a backward photon correlation spectrum. An incident light path consists of a laser, a pane mirror, a lens group, a pinhole aperture and a sample cell. A receiving light path consists of a sample cell, a lens group and a pinhole aperture. An acquisition and processing unit of scattering signals consists of a light detector, a digital correlator and a computer. The measurement steps include that firstly, the laser is used as a light source to irradiate the sample cell filled with particles. Secondly, a photomultiplier is used as a light detector to continuously measure the scattering signals with a scattering angle of 180 degrees. Thirdly, the digital correlator is used to calculate pulse signals output by the photomultiplier and an autocorrelation function, which are input into a computer. Fourthly, the computer works out the diameter of a particle. The invention has the advantages of high precision, fast speed and on-line measurement. Common optical elements are adopted in the light path part. Therefore, the cost of the device is greatly lowered and the device is easy to be maintained.

A time of flight camera includes a light source, a first pixel, a time-to-digital converting, and a controller. The light source is configured to emit light towards an object to be reflected back to the time of flight camera as image light. The first pixel includes a photodetector to detect the image light and to convert the image light into an electric signal. The time-to-digital converter is configured to generate timing signals representative of when the light source emits the light and when the photodetector detects the image light. The controller is coupled to the light source, the first pixel, and the time-to-digital converter. The controller includes logic that when executed causes the time of flight camera to perform operations. The operations include determining a detection window for a round-trip time of the image light based, at least in part, on the timing signals and first pulses of the light. The operations also include determining the round-trip time based, at least in part, on the timing signals and second pulses of the light detected within the detection window.

An optical system and method for characterizing an object is provided. The system includes at least one light source configured to direct photons toward an object and an interferometer configured to receive photons from the object. The system also includes at least one detector system adapted to detect an optical signal at an output of the interferometer and to remove, from the detected optical signal, a signal portion representing first order photon correlations, when present. The system also includes a processor configured to receive data relating to second-order correlated photons from said at least one detector system, each photon or photon pair subject to at least two indistinguishable paths to a photon or photon pair, but differing in at least one of time and length. The processor is configured to characterize the object based on a self interference of the second-order correlated photons from a common location within the object.

The invention provides a method for measuring oscillation frequency and the technical proposal of an oscillation frequency measuring device. The method comprises: the change of scattered light is transmitted to a photomuitplier specially used for photon counting through optical fiber when objects vibrate, the photomuitplier transforms optical signals into electrical signals, and then the electrical signals are transmitted to a photoelectric pulse counter; data output by the photoelectric pulse counter is transmitted to a data processing computer, and the data processing computer utilizes a photon correlation method to process the data; after that, the data is transformed by Fourier, so that power spectrum image and data of oscillation frequency distribution can be obtained. The device is provided with an optical probing unit, an optical transport unit and a data processing unit, wherein, the optical probing unit is connected with the optical transport unit which is connected with the data processing unit, the data processing unit is provided with a photomuitplier module that is electrically connected with an photoelectric pulse counting module, and the photoelectric pulse counting module is electrically connected with the data processing computer; the optical transport unit is optical fiber; the optical probing unit is an optical probing head which is a light input end of the optical fiber.

A method for making a lithographic printing plate includes the steps of (i) providing a negative-working, heat-sensitive lithographic printing plate precursor including a support having a hydrophilic surface or which is provided with a hydrophilic layer and a coating provided thereon, the coating including an image-recording layer which includes hydrophobic thermoplastic polymer particles, a binder, and an infrared absorbing dye, wherein the hydrophobic thermoplastic polymer particles have an average particle diameter, measured by Photon Correlation Spectroscopy, of more than 10 nm and less than 40 nm, and the amount of the IR-dye, without taking into account an optional counter ion, is more than 0.70 mg per m² of the total surface of the thermoplastic polymer particles, measured by Hydrodynamic Fractionation, and the amount of hydrophobic thermoplastic polymer particles relative to the total weight of the ingredients of the imaging layer is at least 60%; (ii) exposing the precursor to infrared light; and (iii) developing the exposed precursor in an alkaline aqueous solution.

Aqueous, structurally viscous powder dispersions curable by free-radical polymerization, substantially or entirely free from volatile organic compounds, and comprising as their disperse phase solid and/or highly viscous particles (A) which are dimensionally stable under storage and application conditions and have a z-mean average particle size as measured by photon correlation spectroscopy of 80 to 750 nm, the particles (A) comprising at least one free-radically crosslinkable binder (A1) having a glass transition temperature of −70 to +50° C., an olefinically unsaturated double bond content of 2 to 10 eq/kg and an acid group content of 0.05 to 15 eq/kg, in an amount, based on (A), of 50 to 100% by weight; process for their preparation, and their use.

A coincidence-counting management method and device are provided. The method comprises the following steps of: receiving a coincidence counting indication instruction and analyzing the coincidence counting indication instruction to obtain a plurality of counting combinations and channel data of each counting combination; according to the channel data of each counting combination, judging whether there is a combination inclusion relationship among the counting combinations, and a plurality of counting combinations in which there is a combination inclusion relationship being divided into the same counting strategy, obtaining photon generation time data of each optical channel corresponding to each counting strategy, and controlling the corresponding thread of the counting strategy to performcoincidence counting on each optical channel corresponding to the counting strategy based on the preset time window width and the corresponding photon generation time data in the time period corresponding to the preset counting time length. The method can save system computational resources, improve coincidence counting efficiency between different optical channel combinations, remove the limitation on the number of optical channels by the equipment, and improve the scheme design flexibility of the photon correlation experiment.

The invention relates to a topical nanoparticulate spironolactone formulation comprising nanoparticles having a mean diameter, measured by photon correlation spectroscopy, in the range of from about 300nm to about 900nm. The nanoparticles are incorporated into a crystalline network system comprising a dispersion of solid crystals of polar lipids, said lipids exposing their hydrophilic side outwards and their hydrophobic side inwards towards the spironolactone nanoparticles.

The invention discloses a PEI nano gel, which is prepared by the prepolymer solution of polyethylene imine on basic condition with pH value not more than 11 and radiation of ultraviolet light. The photon correlation spectrometry shows unimodal distribution for its particle size with dispesion coefficient 0.1-0.7. it also disloses its application as gene transfection carrier. The product has controllable particle size to decrease cytotoxicity and immunogenicity and increase its security and efficiency as carrier in biological medicine field.

Nanoparticles and nanoparticle formulations or suspensions are provided which comprise a fibrate and vitamin E TPGS. The nanoparticles may have a mean diameter, measured by photon correlation spectroscopy, in the range of from about 100 nm to about 900 nm. Pharmaceutical formulations and uses of such compositions are also provided.

The invention relates to an emulsion for aqueous color comprising polymer particles having an average particle size of 20 to 80 nm as measured by the photon correlation method, and including 0.1 to 7 wt % of a structural unit derived from an ethylene-based unsaturated carboxylic acid monomer as the monomer component.