3611 results about "Photodetector" patented technology

The present disclosure relates to an active graded magnetic compensation system and method for an unshielded SERF magnetometer. The system comprises: a detection laser, a half-wave plate, a magnetic field compensation coil, a magnetic field modulation coil, a non-magnetic heating assembly, an alkali-metal atomic vapor cell, a polarizing beam splitter prism, a balanced photodetector, a graded feedback control module, a pump laser, a quarter-wave plate, a focusing lens and a photodetector. By means of the present disclosure, a graded compensation system is used to realize high-precision compensation for a magnetic field within a large dynamic range in a geomagnetic environment, thereby ensuring that an instrument carries out high-sensitivity magnetic field measurement under geomagnetic conditions.

An on-chip mid-infrared micro-ring resonant cavity microfluidic spectrometer is integrated on a substrate material and comprises a spot size converter, an optical coupler, a microfluidic module, a micro-ring resonant cavity, a miniature thin-film resistance heater, a sequential control power supply module, an optical filtering system and a photoelectric detector array. Selective filtering is performed on an input optical signal, and the flow and flow velocity of liquid or gas to be detected are controlled by using the microfluidic module, so that selective absorption of spectral components of the liquid or gas to be detected is realized. In addition, the invention also discloses a mid-infrared integrated optical chip micro-fluidic multiphase detection device comprising the spectrometer and a detection method thereof, the device also comprises a pumping and reference light source module and an on-chip mid-infrared frequency comb generation module, a broadband frequency comb is generated as a light source, a photoelectric detector array is used for collecting signals, and the detection precision is improved. The detection and inversion of the type and concentration of multi-component liquid or gas to be detected are realized, and the on-chip, real-time and micro detection of multi-component substances is realized.

The invention discloses a method for detecting the strain of a key part of a wind turbine generator based on a temperature compensation OFDR demodulation weak fiber bragg grating array, and relates to the technical field of wind turbine generator detection, and the method comprises the steps: installing a weak fiber bragg grating sensor array at the key strain part according to the structural characteristics of the wind turbine generator, a temperature reference grating is arranged in the non-strain area or the constant-temperature area so as to monitor the temperature change in real time; a tunable laser, an optical fiber coupler and a photoelectric detector are utilized to construct an optical frequency domain reflection demodulation system, and system calibration is completed; based on an optical frequency domain reflection demodulation system, reflection spectrum signals are collected, the relation between wind turbine generator strain and temperature change is analyzed through a temperature compensation mechanism, and strain information of key parts of the wind turbine generator is obtained. According to the method, the accuracy and reliability of strain detection are effectively improved, and the problem of measurement errors caused by neglecting the influence of temperature change in a traditional method is solved.

To ensure stable transfer capability. A photodetector includes a semiconductor layer having a first surface and a second surface located on opposite sides, a photoelectric conversion unit in the semiconductor layer that converts, through photoelectric conversion, light incident from a second surface side of the semiconductor layer, a charge holding unit on a first surface side of the semiconductor layer, a transfer transistor that includes a gate electrode and that transfers signal charge generated by the photoelectric conversion unit through the photoelectric conversion to the charge holding unit, and an isolation region on the first surface side of the semiconductor layer. The gate electrode includes a head on the first surface side of the semiconductor layer and legs that extend from the head in a thickness direction of the semiconductor layer and that are in the isolation region adjacent to the semiconductor layer via a gate insulating film.

The invention belongs to the technical field of atmospheric environment monitoring, and particularly relates to an unmanned aerial vehicle laser radar calibration quality control system and method, and the system comprises an unmanned aerial vehicle flight platform, a laser radar module, a navigation positioning module, a control communication module, a data processing module and a ground station. The unmanned aerial vehicle flying platform comprises a shockproof holder and a protective pod; the laser radar module comprises a laser radar, a scanner module and a photoelectric detector module. According to the invention, one unmanned aerial vehicle is adopted to carry various different types of laser radars, the extinction coefficient is measured by combining optical beam splitting, signal processing and algorithm inversion technologies, and atmospheric particulate classification is effectively monitored through cooperation of a high-precision optical system and an algorithm; the extinction coefficient and the depolarization ratio work cooperatively, high-precision quantitative analysis and classification of pollutants can be achieved, the combined measurement function of the extinction coefficient and the depolarization ratio is achieved, and high-resolution three-dimensional monitoring of atmospheric particulates is achieved through multi-parameter cooperative inversion of the laser radar.

A positron emission tomography (PET) scanner includes a plurality of gamma radiation detector modules arranged to form a detector ring. Each detector module includes an array of scintillator detectors. Each scintillator detector comprises a monolithic scintillation crystal and a plurality of photodetector arrays, such as silicon photomultipliers (SiPMs). A photodetector array is positioned on at least two nonparallel faces of each scintillation crystal. In some examples, a photodetector array is positioned on each of three orthogonal faces of each scintillation crystal.

A lithium battery detection device based on BB optical pump magnetic imaging comprises a magnetic shielding cylinder and a substrate arranged in the magnetic shielding cylinder, and a laser, an optical lens system, an atomic gas chamber system, an array lens and an array photoelectric detector are sequentially arranged on the working face of the substrate from left to right; the atomic gas chamber system contains alkali metal atoms and buffer gas; a non-magnetic objective table for placing a lithium battery to be tested is arranged above the atomic gas chamber; according to the device, the array lens is adopted to split and focus a single beam of detection laser into small light spots which are respectively irradiated on different photoelectric detectors, and magnetic field information of a plurality of space point locations is detected at one time, so that the consistency and imaging quality of a subsystem are improved, and the system cost is saved.

Various embodiments of the present disclosure are directed towards an image sensor comprising a pixel with a dual-PD layout for enhanced scaling down. The pixel spans a first integrated circuit (IC) die and a second IC die stacked with the first IC die. The pixel comprises a plurality of photodetectors in the first IC die, and further comprises a plurality of pixel transistors split amongst the first IC die and the second IC die. The plurality of photodetectors are grouped into one or more pairs, each having the dual-PD layout. A DTI structure completely and individually surrounds the plurality of photodetectors, and further extends completely through a substrate within which the plurality of photodetectors are arranged. As such, the DTI structure completely separates the plurality of photodetectors from each other.

The various embodiments described herein include methods, devices, and systems for detecting photons. As described herein, superconducting photodetectors may be coupled with a waveguide such that reflection is reduced / minimized. In one aspect, an optical circuit includes an optical waveguide and a plurality of photodetectors coupled to the optical waveguide, adjacent photodetectors of the plurality of photodetectors being spaced to meet one or more preset destructive interference criteria.

An adjustable bandwidth current-to-voltage converter for use in an optical receiver includes an input configured to receive current from a photodetector; an amplifier stage connected to the input; a feedback path connected to the amplifier stage and to an output, wherein the feedback path includes a feedback element and an operating mode switch configured to set one of photodetector amplifier with dynamic load (PADL) mode and an integrate-and-dump (I&D) mode. The PADL mode is for higher baud operation than the I&D mode.

The invention provides a signal acquisition system of a photoelectric detector. In the signal acquisition system, a transimpedance pre-amplification circuit is arranged at the output end of the photoelectric detector, and a passive high-pass filter circuit is connected between the transimpedance pre-amplification circuit and a post-voltage amplification circuit. And a feedback network is formed in the transimpedance pre-amplification circuit and is used for converting a current signal output by the photoelectric detector into a proportional first voltage signal and outputting the proportional first voltage signal. The filter circuit is a third-order LC high-pass filter circuit and is used for suppressing direct current, low frequency and self-beat frequency components and keeping a 10-90MHz pass band flat. The rear voltage amplification circuit adopts a voltage amplification structure of a voltage operational amplifier, the voltage gain Av is 6-10, and the super-band gain is limited through a shunt capacitor. According to the embodiment of the invention, through the structure and parameter setting, the noise gain peak value is suppressed, and the system stability is improved.

The invention discloses a rotor and stator axial clearance online measuring device and method based on optical carrier microwave interference. The measuring device comprises a broadband light source, a first polarization maintaining optical fiber, an electro-optical modulator, a second polarization maintaining optical fiber, an optical fiber circulator, a first single-mode optical fiber and a coated optical fiber probe which are connected in sequence, and the coated optical fiber probe directly faces the axial end face to be measured; a first port of the optical fiber circulator is connected with the second polarization maintaining optical fiber, a second port of the optical fiber circulator is connected with the first single-mode optical fiber, and a third port of the optical fiber circulator is sequentially connected with the second single-mode optical fiber, the photoelectric detector, the signal conditioning unit, the signal acquisition unit and the digital processing unit; the signal acquisition unit is connected with the micro-control unit, the micro-control unit is connected with the microwave frequency sweep signal generation unit, and the microwave frequency sweep signal generation unit is connected with the electro-optical modulator. According to the invention, non-contact on-line high-precision measurement of the axial clearance of the rotor and the stator of the aero-engine under the conditions of limited measurement space and complex signal leading-out path can be realized.

A subpixel including at least one second-conductivity-type pinned photodiode layer that forms a p-n junction with a substrate semiconductor layer, at least one floating diffusion region, and at least one transfer gate stack structure. The at least one transfer gate stack structure may at least partially laterally surround the at least one second-conductivity-type pinned photodiode layer with a total azimuthal extension angle in a range from 240 degrees to 360 degrees around a geometrical center of the second-conductivity-type pinned photodiode layer. The at least one transfer gate stack structure may include multiple edges that overlie different segments of a periphery of the at least one second-conductivity-type pinned photodiode layer, and the floating diffusion region includes a portion located between the first edge and the second edge. In addition, multiple transfer gate stack structures and multiple floating diffusion regions may be present in the subpixel.

A first portion of incoming light and a second portion of incoming light travel in opposite directions within a first optical waveguide. A ring resonator in-couples the first portion of incoming light and the second portion of incoming light from the first optical waveguide, such that the first portion of incoming light and the second portion of incoming light travel in opposite directions within the ring resonator. A second optical waveguide is disposed to in-couple the first portion of incoming light and the second portion of incoming light couple from the ring resonator, such that the first portion of incoming light and the second portion of incoming light travel in opposite directions within the second optical waveguide away from the ring resonator. One or more photodetector(s) are optically connected to receive the first portion of incoming light and the second portion of incoming light from the second optical waveguide.

The invention discloses a device and a method for measuring an extremely low magnetic field signal, and relates to the technical field of weak magnetic field measurement, and the device comprises a first vector sensor and a second vector sensor which are respectively arranged in the central areas of a first non-magnetic turntable and a second non-magnetic turntable, and the first non-magnetic turntable and the second non-magnetic turntable are respectively and vertically connected with a first support rod and a second support rod; the first supporting rod and the second supporting rod are vertically arranged and are linked through the first gear and the second gear, and the first supporting rod is further provided with a coding disc; when the driving motor drives the first supporting rod to rotate, the first vector sensor and the second vector sensor synchronously rotate and respectively output first and second magnetic field modulation signals; meanwhile, the coding disc synchronously rotates, so that the photoelectric detector outputs an electric pulse reference signal; the analysis module analyzes and processes the received first magnetic field modulation signal, the received second magnetic field modulation signal and the reference signal so as to determine a three-dimensional magnetic field component in the space. According to the invention, accurate measurement of the background magnetic field in the extremely weak magnetic environment is realized.

A method of scanning a field of view implemented by a Light Detection and Ranging (LIDAR) system includes transmitting pulsed light into the field of view; receiving, by a photodetector array, light from the field of view, wherein the photodetector array is configured to receive the light from objects in the field of view corresponding to ambient light and the pulsed light reflected therefrom; generating, by the photodetector array, DC signal components exclusively attributed to receiving the ambient light and AC signal components exclusively attributed to receiving the pulsed light; separating, by a processing circuit, the DC signal components from the AC signal components; generating, by the processing circuit, a two-dimensional image that represents an ambient light image of the field of view from the DC signal components; and generating, by the processing circuit, a three-dimensional image of the field of view from the AC signal components.

A radio system includes a feed network, an edge wavelength switching system (EWSS), a photodetector, and a broadband lens-based antenna subsystem. The feed network aggregates a plurality of unmodulated optical carriers and modulated optical carriers for delivery to an optical link. The EWSS receives the plurality of unmodulated optical carriers and modulated optical carriers from the optical link, and selects a first unmodulated carrier and a first modulated carrier as a first selected optical carrier pair. The photodetector receives the first selected carrier pair from the EWSS and generates a first electrical signal from an optical beat of the first unmodulated carrier with the first modulated carrier. The broadband lens-based antenna subsystem receives the first electrical signal from the photodetector, propagates the received first electrical signal through a lens body, and outputs a first directional wireless beam signal containing signal data from the first modulated carrier.

A disclosed semiconductor photodetector includes a first semiconductor layer having a first refractive index and a first band gap; a second semiconductor layer formed on the first semiconductor layer, the second semiconductor layer having a second refractive index and a second band gap; a first electrode; and a second electrode. The second refractive index is greater than the first refractive index, and the second band gap is smaller than the first band gap. The first semiconductor layer includes a p-type first region, an n-type second region, and a non-conductive third region between the first region and the second region. The second semiconductor layer includes a p-type fourth region in ohmic contact with the first electrode, an n-type fifth region in ohmic contact with the second electrode, and a non-conductive sixth region between the fourth region and the fifth region.

The invention provides a Si-based InGaAs photoelectric detector and a preparation method thereof. The Si-based InGaAs photoelectric detector comprises a Ge transition layer, a GaAs transition layer and a non-doped InP buffer layer, wherein the Ge transition layer, the GaAs transition layer and the non-doped InP buffer layer sequentially grow on the surface of a silicon substrate; the lower doped InP layer, the non-doped InGaAs absorption layer and the upper doped InP layer are sequentially grown on the surface of the non-doped InP buffer layer. The Si-based Ge epitaxial layer, the Ge-based GaAs epitaxial layer and the GaAs-based InP epitaxial layer which are mature in process are sequentially inserted between the Si substrate and the III-V group heteroepitaxial thin film, the crystal structure type difference of direct epitaxial growth of InGaAs on Si is eliminated, the lattice constant mismatch degree is reduced, the defects of the InGaAs epitaxial layer are reduced, the quality is improved, and a high-performance detector is better prepared.

The classical channel employs a transmit laser and classical modulator. The quantum channel employs a nonlinear medium and spontaneous parametric down conversion producing quantum entangled signal and idler photon pairs which are encoded. The classical and quantum channels are combined to define a propagated hybrid signal. The receiver splits the hybrid signal on basis of wavelength into classical and quantum channels. The quantum receiver employs optical parametric amplification, supplied with energy from a second harmonic generation device synchronized to the classical carrier wavelength. A photodetector and extracts a quantum message from the quantum signal.

A ray detector substrate includes: photodetectors including first photodetectors and second photodetectors; and dimming portions including, at a side of each first photodetector away from a substrate, a respective first dimming portion, and, at a side of each second photodetector away from the substrate, a respective second dimming portion. A second scintillator layer is configured to convert part of rays into a first radiation fluorescence. A first scintillator layer is configured to convert another part of the rays into a second radiation fluorescence. The first dimming portion is configured to reflect the second radiation fluorescence, and to enable the first radiation fluorescence to pass through the first dimming portion to be detected by the first photodetector. The second dimming portion is configured to reflect the first radiation fluorescence, and to enable the second radiation fluorescence to pass through the second dimming portion to be detected by the second photodetector.

An electro-optic receiver includes a bus optical waveguide and a plurality of wavelength division multiplexing (WDM) receiver slices positioned along the bus optical waveguide. Each of the plurality of WDM receiver slices includes a WDM element optically coupled to the bus optical waveguide, a photodetector, and a receiver circuit. The photodetector is optically connected to the WDM element by both a first optical connection and a second optical connection. The WDM element conveys a first component of input light through the first optical connection to the photodetector, and a second component of input light through the second optical connection to the photodetector, where first and second components of input light travel in opposite directions through the bus optical waveguide. The receiver circuit generates an electrical data signal from photocurrents received from the photodetector.

The present invention relates to a device for measuring a line current. Said device comprises at least three sensor elements having paramagnetic centres, a pump-radiation source, an optical system, and at least three photodetectors which function as part of receiving systems and are each associated with a sensor element. In addition, the device contains two magnetic field sources which generate different bias magnetic fields for each sensor element. The pump-radiation source emits pump radiation into the optical system, which distributes the pump radiation to the sensor elements and thereby irradiates the paramagnetic centres with the pump radiation. These centres emit fluorescence radiation, the intensity and phase shift of which depend on the AC drive signal of the evaluation and control device and on the magnetic flux density acting upon them. The fluorescence radiation is separated from the pump radiation by the optical system and guided onto the photodetectors. The evaluation and control device generates a single-frequency sinusoidal AC drive signal having a frequency of 22 MHz (-4 MHz / +7 MHz), or within a range of 18 MHz to 29 MHz. The lock-in amplifiers are coupled to the sensor elements and evaluate the output signal of the photodetectors with respect to the AC drive signal in order to produce measurement values. Based on these measurement values, the evaluation and control device determines an estimated value for the magnitude of the line current in the line.

To provide a photodetector capable of protecting a semiconductor photodetector element from reflected electrons generated inside a vacuum enclosure.SOLUTION: A photodetector 1 includes a vacuum housing 2 having a window 12, a photocathode (first photoelectric conversion layer) 3 that emits electrons E in response to incidence of light L1, a phosphor layer (second photoelectric conversion layer) 4 that generates light L2 in response to incidence of the electrons E emitted from the photocathode 3, and a semiconductor photodetector element 5 that is disposed on the opposite side of the photocathode 3 with the phosphor layer 4 in between and detects the light L2 generated in the phosphor layer 4. The semiconductor photodetector element 5 is disposed at a distance from the phosphor layer 4.SELECTED DRAWING: Figure 1

The invention provides a quartz enhanced photoacoustic spectrometry detection system environment gas interference correction method which can be applied to the technical field of photoacoustic spectrometry gas detection. The method comprises the following steps: analyzing vibration-translation relaxation time and infrared absorption peak intensity of each gas to be detected; the to-be-detected gas with the vibration-translation relaxation time exceeding the time threshold value and the absorption peak intensity larger than the intensity threshold value is selected as comparison gas; dividing the laser of the comparison gas into a first laser beam and a second laser beam according to a preset proportion; using the first laser beam to excite a sound wave signal and detecting by a quartz tuning fork to generate a tuning fork electric signal; the second laser beam is enhanced and absorbed by a multi-reflection absorption cell and then is detected by a photoelectric detector to generate a light intensity electric signal; establishing a neural network model taking the tuning fork electric signal, the light intensity electric signal and the environment gas component vector as input and taking the to-be-detected gas concentration vector as output; and correcting the concentration of the to-be-detected gas under the interference of the environmental gas in real time through the trained neural network model.

The invention provides a spectrograph based on a fast adjustable filter, the spectrograph comprises the fast adjustable filter, a photoelectric detector, a data acquisition card and a spectrum reconstruction module which are connected in sequence, the fast adjustable filter successively filters spectral components of different wavelengths in the working bandwidth of the spectrograph in sequence, and after each filtering, the spectral components of different wavelengths in the working bandwidth of the spectrograph are obtained. The photoelectric detector detects an optical signal with corresponding light intensity and converts the optical signal into an electric signal, and when the wavelength of the filtered spectral component is within the wavelength range of the to-be-detected light, the light intensity of the optical signal and the current of the electric signal are reduced; the data acquisition card performs current acquisition on each electric signal in sequence to obtain a to-be-measured current vector; the spectrum reconstruction module reconstructs the light spectrum to be measured according to the collected current vector to be measured and a pre-stored spectrum transmission matrix. The spectrograph is high in detection speed, small in size and simple in detection method.

The invention provides a state-adjustable double-gain optical structure on a silicon substrate and a laser radar system, and relates to the technical field of laser radars. The adjustable double-gain optical structure on the silicon substrate comprises a first reflection type semiconductor optical amplifier, a second reflection type semiconductor optical amplifier, a first phase modulator, a second phase modulator, a first optical coupler, a third phase modulator, a fourth phase modulator, a second optical coupler, a first port and a second port. A reflected light electric field and a transmission light electric field are adjusted by adjusting the phase difference between the two reflection type semiconductor optical amplifiers. A laser radar system is formed by a plurality of state-adjustable double-gain optical structures on a silicon substrate, a transmitting optical phased array, a receiving optical phased array, a balanced photoelectric detector and the like, the transmitting power of the transmitting optical phased array is flexibly adjusted, meanwhile, a plurality of reflection type semiconductor optical amplifiers are adopted, the laser radar power is remarkably improved, and the laser radar system is suitable for large-scale popularization and application. And long-distance detection of the laser radar system based on the optical phased array is realized.

A measurement spectrum obtained by irradiating a particle labeled with a plurality of fluorescent dyes with excitation light is separated for each fluorescent dye with high accuracy. Provided is a particle analysis system (1) including a plurality of photodetectors (23) configured to acquire light generated by irradiating a particle labeled with a plurality of fluorescent dyes with excitation light; and an information processing unit (132) configured to calculate fluorescence intensity of each fluorescent dye by performing separation processing on a measurement spectrum based on measured values from the plurality of photodetectors (23) with a single staining spectrum of each fluorescent dye, in which the separation processing is performed by using a weighted least squares method (WLSM) including a weight determined based on a variation in the measured values.

An image sensor structure including a substrate, a pixel structure, and a deep trench isolation (DTI) structure is provided. The substrate includes a first side and a second side opposite to each other. The pixel structure includes a transfer transistor, a light sensing device, and a floating diffusion region. The transfer transistor includes a first gate. The first gate is disposed on the first side of the substrate. The light sensing device is disposed in the substrate and is located on one side of the first gate. The floating diffusion region is disposed in the substrate and is located on another side of the first gate. The DTI structure extends into the substrate from the second side of the substrate. The top-view pattern of the floating diffusion region does not overlap the top-view pattern of the DTI structure.

The invention discloses a depth time delay reserve pool calculation method based on an electric cascade photoelectric feedback laser. An adopted depth time delay RC system comprises a T-shaped bias device, a semiconductor laser and a photoelectric detector. A signal of the input layer is injected into the first-layer storage pool through the T-shaped bias device; an optical signal output by a laser 1 is divided into three paths after passing through a photoelectric detector, one path returns to the laser 1 through a feedback time delay loop, one path is injected into a second-layer storage pool through a T-shaped bias device, and the other path reaches an output layer to obtain a virtual node state of a first layer; an optical signal output by the laser 2 is divided into two paths after passing through a photoelectric detector, one path returns to the laser 2 through a feedback time delay loop, and the other path reaches an output layer to obtain a virtual node state of a second layer; and finally, linearly weighting the virtual nodes of the two layers of reserve pools to obtain the output of the system. According to the invention, real layering, high dynamic adjustability and excellent integration feasibility of the system structure are realized, and the system is more suitable for processing complex tasks in the real world.