55 results about "Spontaneous emission" patented technology

The invention provides a semiconductor defect detection method and device based on short-medium wave infrared microscopic imaging, and the method comprises the steps: selecting a short-medium wave infrared band with the wavelength greater than or equal to 2.5 microns as a detection working band, and employing an infrared light source capable of covering the detection working band and a corresponding infrared area array detector; constructing an infrared microscopic imaging light path, and irradiating light emitted by an infrared light source to the surface of a sample through an infrared illumination light path after passing through a beam splitter and an infrared microscopic objective lens; sample reflected light is collected through an infrared microscope objective and is imaged on an infrared area array detector; two-dimensional view field scanning is performed on the sample, imaging is realized through a focusing mechanism, and surface and internal defects are detected; the infrared light source is modulated, so that signal light reflected by the sample is an alternating-current signal, the alternating-current signal is separated from direct-current noise spontaneously radiated by the background, and internal defects of the semiconductor sample are detected after the noise is filtered and the signal-to-noise ratio of an image is improved. The invention provides a high-sensitivity and high-resolution solution for semiconductor defect detection.

A reconfigurable optical add / drop multiplexer using a wavelength selective switch (WSS) component to multiplex wavelength channels into a wavelength division multiplexed (WDM) signal. When a given channel is dropped, an amplified spontaneous emission (ASE) injection signal is multiplexed as a ghost channel into the WDM signal. The ASE injection channel can mitigate polarization hole burning and can provide a fuller power spectrum density. However, the ASE injection channel also defines a monitoring window. As an optical channel monitor (OCM) monitors the WDM signal, the OCM can detect, within the monitoring window, any underlying characteristic of the given wavelength channel. In this instance in response to the detected characteristic, the WSS component switches from multiplexing the ghost channel into the WDM signal to multiplexing the given wavelength channel into the WDM signal.

The invention discloses a high-temperature high-density plasma generation and radiation opacity measurement method, which comprises the following steps: clamping a target material by using low-density low-Z-element foam to form a sandwich structure sample, and synchronously and directly driving the sandwich sample from two sides by using multiple beams of smooth nanosecond laser, the preparation temperature reaches 1,000,000 DEG C, and the electron density reaches 1 * 1023 pieces per cubic centimeter; then generating an X-ray source through the action of one or more nanosecond laser beams and the high-Z material, measuring the absorption spectrum of the X-ray source penetrating through the target plasma, the backlight spectrum of the X-ray source not penetrating through the target plasma and the self-emission spectrum of the target plasma through a spectrograph, and finally realizing the measurement of the radiation opacity of the high-temperature and high-density plasma. The high-temperature and high-density plasma radiation opaqueness measurement device has the beneficial effects that the high-temperature and high-density plasma radiation opaqueness measurement of which the temperature reaches 1,000,000 DEG C and the electron density reaches 1 * 1023 per cubic centimeter is realized on a million-joule nanosecond laser device.

This invention provides a highly efficient method for separating or concentrating lattice defect-containing nanoparticles (NDs). [Solution] A method for separating or concentrating lattice defect-containing ND particles, comprising irradiating a dispersion containing at least two types of ND particles selected from nanodiamond (ND) particles having at least one type of lattice defect and ND particles without the lattice defect with at least one type of excitation laser light having an energy greater than or equal to the resonance absorption energy of the lattice defect and at least one type of stimulated emission laser light, thereby selectively moving the ND particles having the lattice defect by the absorption optical pressure generated by the absorption of at least one type of excitation laser light and the stimulated recoil force generated by the action of at least one type of stimulated emission laser light, wherein the excitation laser light transitions electrons in the ground state of the ND particles to an excited state, and the stimulated emission laser light transitions electrons in the excited state to the ground state faster than spontaneous emission to generate stimulated recoil force.

This invention claims protection for a laser device and optical path debugging method for acquiring micro-sized beams, belonging to the field of solid-state laser technology. The device structure includes: an indicator light source, a high-gain module, a micro-sized pinhole aperture, a micro-sized output mirror, and a micro-sized reflector. The debugging method consists of the following steps: S1: Determine the pitch and yaw of the micro-sized reflector using the indicator light source and the micro-sized pinhole aperture; S2: Determine the spontaneous emission light path of the high-gain module based on the micro-sized reflector and the two micro-sized pinhole apertures; S3: Add the micro-sized output mirror to achieve laser resonator oscillation based on the micro-sized cavity mirror. Because the cavity mirror is small enough, this invention eliminates the need for external pinhole beam contraction, reducing diffraction effects. Furthermore, by using an internal pinhole aperture to determine the optical path, it solves the problem of the spontaneous emission amplification optical path of the module not coinciding with the resonator oscillation optical path, improving output power and meeting the requirements for outputting micro-sized beams based on a high-gain module.

A kind of water environment cadmium ion and temperature double parameter optical fiber chemical sensing system relates to water body environment detection field.In the above system, spontaneous emission light source is near infrared light source;The surface of optical fiber sensing unit is coated with magnetic MOF-cadmium ion imprinted polymer;The light signal generated by spontaneous emission light source enters optical fiber sensing unit, optical spectrometer collects the transmission spectrum signal of optical fiber sensing unit, and the collected spectrum data are output to photoelectric detection module;Photoelectric detection module converts light signal into electrical signal and transmits to demodulation module;Demodulation module gives the cadmium ion concentration and temperature according to input signal using machine learning algorithm.The present application has higher specific recognition ability to cadmium ion, and can effectively separate the coupling influence of cadmium ion concentration and temperature on sensing signal.

Since it is difficult to constantly monitor a large number of unused fiber optic transmission lines in an optical submarine cable system, a light source device according to the present invention includes: a light generation unit for generating amplified spontaneous emission light; a light control unit for controlling the band and power of the amplified spontaneous emission light and generating waveform shaping spontaneous emission light; and an optical branching unit for branching the waveform shaping spontaneous emission light into a plurality of branched light beams.

The invention discloses an ultra-wideband weak signal detection method and system based on all-optical oscillation and phase-amplitude conversion. The method comprises the steps that spontaneous radiation light generated by an erbium-doped optical fiber amplifier is used as an optical carrier; modulating a weak radio frequency signal to be measured received by an antenna to the optical carrier through an optical modulator to form a modulated optical signal; the modulated optical signal is injected into an all-optical oscillation circuit composed of double loops, the all-optical oscillation circuit generates multimode optical oscillation by adjusting an optical attenuator, and the all-optical oscillation circuit comprises a double-loop interference structure; performing phase-amplitude conversion by adjusting the delay difference of the two light paths in the double loops to form an equivalent microwave photon filter so as to select and amplify the modulated light signal corresponding to the radio frequency signal of the set frequency band; and converting the selected and amplified modulated optical signal into an electric signal, and performing spectral analysis to detect the weak radio frequency signal to be detected.

The invention provides a coaxiality correction optical system and a coaxiality correction method and device, and relates to the technical field of laser communication.The coaxiality correction optical system comprises a light emitting and processing module, a light transmission module, an emitting correction module, a receiving correction module and a detection module; the spontaneous radiation light generated by the light emitting and processing module for laser communication is used as the calibration light source, so that an independent calibration light source does not need to be additionally arranged, and the light path complexity of the laser communication terminal is effectively reduced; and the same detection module is used for imaging the spontaneous radiation light, the reflected light of the emitted first signal light and the reflected light of the received second signal light, so that the coaxiality of the emission optical axis, the receiving optical fiber optical axis, the tracking receiving optical axis and the calibration emission optical fiber optical axis of the laser communication terminal is monitored and corrected in real time at the same time. Accurate real-time monitoring and correction of the coaxiality of the transmitting and receiving optical axes of the laser communication terminal are realized.

The invention provides a fault protection system and method for an MOPA structure fiber laser. Wherein the system comprises: an amplification stage; a main seed source; the detection module is used for monitoring the working state of the amplification stage in real time, determining a fault position in the amplification stage and generating a fault trigger signal when an abnormality is monitored; and the protection module is used for blocking an input light path and an output light path of the fault position through the isolation sub-module within a preset response time after receiving the fault trigger signal, and providing alternative seed light for a downstream amplifier through the seed supply module if the downstream amplifier exists at the fault position, so that the fault position is detected. And at least closing the amplifier corresponding to the fault position through the closing sub-module. According to the invention, the amplifier at the fault position is isolated, signal injection and intelligent closing of the downstream amplifier are maintained, and effective protection of bidirectional amplified spontaneous emission hazards is realized.

The application discloses a kind of high pumping efficiency low nonlinear effect fiber laser, sequentially connected seed source, isolator, first circulator, first combiner, first gain fiber, fiber grating, second gain fiber, second combiner, second circulator, still include first pump source, second pump source and output collimator;Fiber grating is total reflection grating, center wavelength is consistent with seed light wavelength, is set between first gain fiber and second gain fiber;Utilize fiber grating, realize the original light path reflection of seed light and secondary amplification, while pumping light transmission to fiber grating will be transmitted to continue transmission.The application can increase the action distance of seed light and gain fiber under the condition that gain fiber is shorter, secondary amplification is carried out to seed light, while effectively inhibiting spontaneous emission effect and nonlinear effect in fiber laser, while secondary utilization is carried out to residual pumping light, effectively improve pumping efficiency, and improve fiber laser performance.

The invention discloses a controlled aerosol laser-induced breakdown spectroscopy detection method and device, and relates to the technical field of laser plasma emission spectroscopy. The method comprises the following steps: placing a to-be-detected sample with fixed mass in a closed cavity filled with inert gas; ablating all the to-be-detected samples in the closed cavity by using laser with fixed wavelength, mixing ablated to-be-detected sample particles with inert gas to form aerosol with uniform mass density, and exciting the aerosol to form plasma; the plasma spontaneously emits light; one or more of pressure intensity, double-pulse excitation and resonance excitation in the closed cavity are regulated and controlled, so that the intensity of light emitted by the plasma is enhanced; and obtaining the content of the to-be-analyzed element in the to-be-detected sample according to the intensity-enhanced plasma emitted light. According to the method, the influence of the matrix effect on the laser-induced breakdown spectroscopy technology can be reduced, and the quantification accuracy is improved.

The invention provides an optical fiber amplifier which comprises a gain light path used for amplifying signal light; the first filter is used for filtering backward spontaneous radiation light generated when the gain light path amplifies the signal light and retaining auxiliary light meeting preset requirements; and the coupler is used for combining the auxiliary light and the new signal light to be amplified by the gain light path so as to enhance population inversion generated by amplifying the new signal light by the gain light path after beam combination. When the optical fiber amplifier amplifies the signal light, the signal light can generate stronger population inversion, so that the noise coefficient is effectively reduced, and the transmission quality of the signal light can be improved after the optical fiber amplifier is deployed to an optical communication network.

An optical signal amplification apparatus and a related optical communication device. The apparatus may include a pump light source, a combiner assembly, a doped optical fiber, and an optical filter. The pump light source may be configured to emit a pump beam. The combiner assembly is configured to combine a signal beam and the pump beam and couple a combined beam into the doped optical fiber. The doped optical fiber is configured to amplify the signal beam under excitation by the pump beam. The signal beam includes one or more single-wavelength signals. The optical filter is disposed between two ends of the doped optical fiber and configured to transmit the signal beam and filter out a first beam in the doped optical fiber. The first beam includes a beam of some wavelengths or all wavelengths generated by spontaneous emission in the doped optical fiber.

The application discloses a temperature and gas detection system and method based on ultraviolet to near infrared spectrum, relates to the technical field of spectrum measurement, and solves the technical problem that the prior art adopts two separate devices to respectively measure temperature and monitor the environment in a smelting process, occupies space in a smelting furnace, and increases the complexity of the system; the application obtains spontaneous emission light of a target to be detected; the spontaneous emission light is dispersed and spectrally analyzed to obtain spectrum data of the full wave band of ultraviolet to near infrared light; the spectrum data are denoised to obtain the spectrum of the target to be detected; temperature data are obtained according to spectrum analysis of the target to be detected; and the concentration of gas is calculated based on the spectrum and a pre-established spectrum database; the temperature of the target to be detected can be accurately measured, and the measurement accuracy is improved.

The present application provides an optical fiber amplifier, comprising: a gain optical path, configured to amplify signal light; a first filter, configured to filter backward spontaneous emission light generated by the amplification of the signal light by the gain optical path, and retain auxiliary light that meets a preset requirement; and a coupler, configured to combine the auxiliary light with new signal light to be amplified by the gain optical path, so as to enhance population inversion generated when the combined new signal light is amplified by the gain optical path.

The utility model discloses an embodiment of amplifying spontaneous emission light source. The amplifying spontaneous emission light source includes seed source and power amplifier, and the seed source is used for outputting the wide spectrum signal light of 900nm to 930nm wave band, and the power amplifier includes first doped neodymium optical fiber, first pump source and beam combiner, and the first pump source is used for outputting the first pump light, and the input end of beam combiner is connected with the output end of seed source and the output end of first pump source respectively, and the output end is connected with the input end of first doped neodymium optical fiber, and the first pump light is used for pumping neodymium ion in first doped neodymium optical fiber, so that neodymium ion is stimulated emission, and the seed signal light is amplified. The utility model solves the problem that the output power of the existing 900nm to 930nm wave band wide spectrum spontaneous emission light source is low, and it is difficult to fully meet the application requirement of high power nonlinear frequency multiplication, and realizes the stable output of high power amplifying spontaneous emission light with the center wavelength of 910-930nm.

The application discloses a kind of wavelength greater than 2.1 microns all-fiber short-cavity thulium-doped fiber laser oscillator, including sequentially connected fiber output 1.5 microns pulse pump source, 1.5 / 2 microns fiber wavelength division multiplexer and a section of non-polarization thulium-doped fiber, thulium-doped fiber both ends are engraved with a Bragg fiber grating, 1.5 microns pump light is generated by reverse, core pumping thulium-doped fiber reverse output dominant 2.1 microns above wavelength band laser signal, and along thulium-doped fiber positive single pass 1.8 microns broadband amplified spontaneous emission, the amplified spontaneous emission as a second reverse pump source, the gain of 2.1 microns above wavelength band is improved, and the pulse laser output greater than 2.1 microns is generated.The application structure is compact, simple, can replace holmium-doped fiber laser to realize wavelength greater than 2.1 microns high efficiency, high peak power laser output.

The disclosed light source device includes a light emitting element including a first reflector, a second reflector, and a resonator spacer portion provided between the first reflector and the second reflector and including an active layer, and emits a first light as a laser beam and a second light as a spontaneous emission light, a light receiving element that determines an amount of the second light, and a determination unit that determines a timing at which the first light oscillates based on a decrease in the amount of the second light determined by the light receiving element.

A communication system is disclosed that features a computing device, a radiating element coupled to the computing device and including a primary helical coil, a secondary helical coil positioned within the primary helical coil, one or more inductor coils that are free to rotate positioned within the secondary helical coil, an optohelical antenna, a central core positioned within the one or more inductor coils, one or more central core coils positioned within the central core, and a central core cavity positioned within the one or more central core coils, in which the central core cavity includes a plasma and / or a gain medium which exhibits magnetic resonance, spontaneous emission, stimulated emission, and / or absorption. The communication system includes a signal injection circuit, a signal detection circuit communicatively coupled to the computing device, and a control module communicatively coupled to the computing device to determine a mode of a transceiver module.

The embodiment of the invention provides an active alignment assembly method and system for a laser module and related equipment, and aims to improve the repeated assembly precision of an optical lens of the laser module and reduce the hardware cost and the system debugging difficulty. The method provided by the embodiment of the invention comprises the following steps: controlling the driving current of the semiconductor laser chip to be lower than the threshold current of the semiconductor laser chip, so that the semiconductor laser chip is in an incoherent light-emitting mode; light emitted by the semiconductor laser chip in the incoherent light emitting mode is spontaneous radiation incoherent fluorescence and is used for illuminating micro-textures of a light emitting surface of the semiconductor laser chip; a micro texture image of the light-emitting surface of the semiconductor laser chip after conjugate imaging through the optical lens to be assembled is collected through an imaging unit; and adjusting the relative position of the optical lens to be assembled and the semiconductor laser chip according to the detection signal intensity of the micro texture image, and recording the optimal position of the optical lens to be assembled relative to the semiconductor laser chip.

An apparatus for pseudo thermal light source ghost imaging and range sensing using narrow-band spontaneous emission includes: a pseudo thermal light source including a resonator type laser diode; a temperature controller configured to control a temperature of the pseudo thermal light source; a current controller configured to control a current of the pseudo thermal light source; a beam splitter configured to split a laser beam emitted from the pseudo thermal light source into a first beam and a second beam; and a temporal correlator configured to infer a target range to an object through temporal coherence between the first beam and the second beam, wherein the pseudo thermal light source oscillates a laser beam having second order coherence when a specific current is applied according to temperature.

The utility model relates to the technical field of optical fiber laser, concretely is a kind of device for reducing with signal same wavelength spontaneous emission light, including first collimator, polarized light prism, optical rotatory component, attenuation component and reflector being sequentially arranged along light path, and second collimator opposite with polarized light prism side face.The device for reducing with signal same wavelength spontaneous emission light, by the structure and parameter of each component of reasonable setting, utilize polarization characteristics and the mode of multiple attenuation, can effectively reduce with signal same wavelength spontaneous emission light, application test in laser radar scene shows that when not using the device, radar test signal-to-noise ratio is-3dB, signal is submerged in noise, cannot measure useful signal;After using the device, after spontaneous emission light attenuation, radar test signal-to-noise ratio reaches 18dB, has obvious improvement, significantly improves system performance, ensures the normal work of system under weak signal light scene.

A photonic circuit Ti: sapphire optical amplifier is provided. Critical aspects of the technique include near perfect mode overlap between the signal and the pump in the amplifier waveguide, and low loss wavelength division multiplexing techniques for separating / combining the signal and the pump. Applications include various amplifier configurations, narrow linewidth photonic circuit lasers, and photonic circuit incoherent amplified spontaneous emission sources.

The invention relates to an ASE light source capable of achieving full-temperature power stability and an implementation method. The ASE light source comprises a grating, an isolator, a wavelength division multiplexer, an erbium-doped fiber and a pump laser. The pump laser is used for providing pumping light, the pump laser is connected with one end of the erbium-doped optical fiber through the optical wavelength division multiplexer, the other end of the erbium-doped optical fiber is coiled into a small circle or cut into an oblique angle, and the backward amplified spontaneous radiation light passing through the erbium-doped optical fiber is output through the wavelength division multiplexer, the optical isolator and the optical fiber filter in sequence; a circuit of the pump laser comprises a TEC control circuit unit and a laser driving circuit unit. The pump laser driving circuit unit comprises an ADN2830 chip, a sampling resistor and a chip peripheral circuit; the sampling resistor is formed by connecting a fixed resistor and a linear temperature-sensitive resistor in series, the driving size of the pump laser is controlled by changing the size of the sampling resistor, and stable output of optical power under the full-temperature working condition is achieved. According to the invention, the complexity of the light path is reduced, and the reliability of the light path is improved.

Various examples are provided related to single channel and multi-channel radio frequency (RF) steganography. In one example, a method includes generating an amplified spontaneous emission (ASE) broadband signal; spectrally slicing the ASE broadband light to achieve taps for generating a dynamic photonic finite impulse response in an RF domain; generating a stealth-modulated broadband optical carrier by combining a stealth signal with the spectrally sliced ASE broadband light; passing the stealth-modulated broadband optical carrier to a dispersive medium to achieve the dynamic photonic FIR in the RF domain; and transmitting the stealth-modulated optical comb carrier via a transmission fiber. The ASE broadband light can have wavelength and intensity corresponding to background noise of a photonic system. In another example, a system for RF steganography includes a stealth transmitter. The stealth transmitter can generate and transmit the stealth-modulated optical comb carrier to a stealth receiver via a transmission fiber.

The application discloses a method and device for improving the spontaneous emission time contrast of femtosecond laser pulses. The device comprises a titanium sapphire femtosecond laser oscillator, a laser pump source, a stretcher, a regenerative amplifier, an electro-optical switch, a compressor and the like. The low-energy pulses output by the femtosecond laser oscillator are time-domain stretched by the stretcher, and then are sent into the regenerative amplifier for amplification. At this time, the transmittance of laser pulses of different wavelengths in the ring cavity is adjusted by adjusting the incident angle of the laser into the spectrum shaping filter in the ring cavity, so as to suppress the spontaneous emission in the cavity and improve the spontaneous emission time contrast of the amplified light. Subsequently, the electro-optical switch is controlled to make the amplified light enter the pulse compressor, and finally the femtosecond laser pulses with high energy and high time contrast are generated. The application improves the spontaneous emission time contrast of femtosecond laser pulses by spectrum shaping filtering in the ring cavity of the amplifier, and can also effectively suppress the spectral red shift and gain narrowing of the amplified light, and output the amplified light with a wide spectrum.

The present disclosure relates to an optical fiber amplifier comprising a first amplification stage comprising a first active fiber configured to amplify light received from a seed laser or a pre-amplifier stage; a second amplification stage comprising a second active fiber configured for further amplifying light received from the first amplification stage, wherein the second active fiber is configured for supporting only a single mode of light; and an optical device configured for at least partially coupling out undesired light from the optical fiber amplifier, said undesired light being generated from amplified spontaneous emission (ASE) and having a center wavelength of about 1 µm; wherein the first and second active fibers are Er / Yb co-doped double-clad fibers, wherein the optical fiber amplifier is configured for amplifying light having a center wavelength in the range from about 1535 nm to about 1580 nm The present disclosure further relates to a laser system comprising the optical fiber amplifier.

The application provides a multifunctional reconfigurable hybrid integrated laser, comprising: a gain chip 1 and a silicon-based chip 2; the gain chip 1 and the silicon-based chip 2 are hybrid integrated through edge coupling; the gain chip 1 is used as an optical gain unit to output wide-spectrum spontaneous emission light; and the silicon-based chip 2 is used as a filtering and tuning unit to construct a laser resonant cavity to realize laser output and laser wavelength tuning. The application is integrated as a whole into a hybrid integrated module, multifunctional reconfiguration of output laser is realized, and the application can be applied to different application scenarios such as wavelength division multiplexing and laser radar.

A laser cooling system and a method of laser cooling are disclosed. The laser cooling system includes a multi-pass optical cavity; a first mirror positioned at a first end of the multi-pass optical cavity; and a second mirror positioned at a second end of the multi-pass optical cavity, wherein the first mirror or the second mirror comprises a spectrally selective coating to suppress amplified spontaneous emission (ASE) and parasitic lasing to avoid undesired heat generation in a material being cooled in the multi-pass optical cavity.