17 results about "Harmonic radiation" patented technology

The invention provides an S-band radio frequency signal transmitting port and a design and assembly method thereof, relates to the technical field of special equipment for radio frequency communication, and solves the problem of insufficient harmonic suppression caused by an infeasible shielding structure or a defect of a connection interface in the existing scheme. The transmitting port comprises a structural cavity, a printed circuit board and a plurality of SMA connectors, the printed circuit board is accommodated in the structural cavity, a transmitting circuit is arranged on the printed circuit board, and the structural cavity is used for providing radio frequency shielding for the printed circuit board; the SMA connectors are assembled on the outer surface of the structural cavity, and pins of the SMA connectors penetrate through the structural cavity and then are connected with the printed circuit board. The peripheral edge of the printed circuit board is provided with a non-solder-resist area with a preset width, and when the printed circuit board is accommodated in the structural cavity, the non-solder-resist area of the printed circuit board is in tight fit connection with the inner surface of the structural cavity. According to the invention, a closed shielding frame body is formed, so that higher harmonic radiation leakage is prevented.

A method for treating near-retina floaters includes dilating a pupil of an eye of a patient to at least 6.6 millimeters (mm). While the pupil is dilated to at least 6.6 mm, the method further includes emitting, by an optical delivery system, a plurality of pulses from a treatment laser into the eye of the patient, each pulse of the plurality of pulses having a diameter upon passing through the pupil that substantially fills the pupil and having a focus within 3 mm of a retina of the eye of the patient. Pulses may pass through adaptive optics that may be adjusted based on light emitted from the eye, such as two-photon fluorescence or second harmonic radiation, in order to reduce spot size at the focus.

The application discloses a light source device, a system and a water window band full-coherent free electron laser generating method. The device comprises: a harmonic generation unit for connecting an electron beam and a seed laser and generating low-order harmonics; at least two cascaded amplifier units connected with the harmonic generation unit, for connecting the low-order harmonic radiation and generating coherent harmonic radiation, and for tuning the coherent harmonic laser to high-order harmonic radiation to obtain water window band full-coherent free electron laser pulses. The application constructs a multi-stage amplifier unit in the rear stage of the harmonic generation unit, and each subsequent amplifier unit is configured to resonate on a high-order harmonic of the radiation output by the previous amplifier unit, so that the harmonic radiation of the previous stage is used as the effective seed of the subsequent stage, the frequency is up-converted stage by stage, the frequency of the coherent radiation is converted to the target high-order harmonic stage by stage, and the water window band full-coherent free electron laser is obtained.

The invention discloses a method for realizing regulation and control of a second harmonic radiation direction, which adopts a semiconductor-graphene nonlinear composite structure, and realizes modulation of a second harmonic far-field scattering mode by regulating and controlling the Fermi level of graphene. The semiconductor-graphene nonlinear composite structure comprises anisotropic nanoparticles coated with graphene, the nanoparticles can be of a single independent structure or a dimer structure formed by a plurality of nanoparticles, and when the nanoparticles are of the dimer structure, a gap exists between every two nanoparticles. The invention provides an effective and convenient method for flexibly modulating a second harmonic nonlinear far-field scattering mode by utilizing the high tunability of the optical nonlinear characteristic of the graphene.

This invention belongs to the field of nonlinear optics and extreme ultraviolet coherent light source technology, specifically relating to a method for generating a quasi-monochromatic circularly polarized extreme ultraviolet light source. The method involves: constructing a reverse-rotating bicolor circularly polarized laser field as the driving light source; this reverse-rotating bicolor circularly polarized laser field is a superimposed field of reverse-rotating circular polarization composed of a fundamental frequency light field and a second harmonic light field; in a vacuum environment, the reverse-rotating bicolor circularly polarized laser field is coincident in time and space and focused into a medium to generate high-order harmonic radiation; by adjusting the relative intensity of the fundamental frequency light field and the second harmonic light field, a quasi-monochromatic circularly polarized extreme ultraviolet light source is generated; the medium is an atomic, ionic, or unarranged molecular system. The method of this invention is simple to implement experimentally, and the resulting circularly polarized extreme ultraviolet light source has high monochromaticity and high polarization purity, solving the problem of previous methods for generating quasi-monochromatic extreme ultraviolet light sources that relied on complex media and could not simultaneously achieve monochromaticity and circular polarization state.

The application discloses an arbitrary dielectric constant end-fire leaky-wave antenna based on subarray alternation, which comprises an upper metal, a dielectric substrate and a lower metal arranged in sequence from top to bottom; the upper metal comprises a first metal wire and a first subarray alternately arranged on both sides of the first metal wire; the lower metal comprises a second metal wire and a second subarray alternately arranged on both sides of the second metal wire; the first subarray and the second subarray are symmetric to the axis of the first metal wire and the second metal wire; and the subarrays of the first subarray and the second subarray contain the same number of one or more radiation units. The antenna can generate a stable end-fire radiation pattern through space-1 harmonic radiation, can realize the end-fire leaky-wave antenna on a lower dielectric constant dielectric substrate, can reduce the processing difficulty, and can realize a higher gain length ratio and a larger gain bandwidth.

The embodiment of the invention relates to the technical field of communication, and discloses an antenna array and communication equipment, and the antenna array comprises an antenna support, a low-frequency radiation branch knot, an intermediate-frequency radiation branch knot, a high-frequency radiation branch knot, a feed structure, and a grounding structure. The low-frequency radiation branch knot, the intermediate-frequency radiation branch knot, the high-frequency radiation branch knot, the feed structure and the grounding structure are all arranged on the antenna support, the intermediate-frequency radiation branch knot and the low-frequency radiation branch knot are arranged adjacently, and the high-frequency radiation branch knot and the intermediate-frequency radiation branch knot are arranged adjacently. The low-frequency radiation branch knot, the intermediate-frequency radiation branch knot and the high-frequency radiation branch knot interact through electromagnetic coupling, and the high-frequency radiation branch knot realizes high-frequency signal transmission through harmonic radiation of the low-frequency radiation branch knot and the intermediate-frequency radiation branch knot. And important technical support is provided for compact design of small communication equipment.

The application relates to the technical field of strong-field high-harmonic generation, and particularly discloses a double-electron quantum correlation quantitative method and system based on Bohm mechanics, which comprises the following steps: establishing a time-dependent Schrodinger equation containing an external laser field, obtaining a system ground state wave function and generating N pairs of Bohm particles initial coordinates, and performing time evolution on the wave function; according to the evolved wave function, the accurate velocity field and the accurate motion trajectory of each Bohm particle are calculated; based on the marginal probability density and the marginal probability flow density, the marginal velocity field not containing instantaneous quantum correlation effects is constructed, and the corresponding correlation-free reference trajectory is generated; the accurate trajectory is compared with the reference trajectory, and the correlation model of the correlation quantum potential and the high-harmonic radiation intensity is established. Through comparison of the accurate Bohm trajectory and the correlation-free reference trajectory constructed based on the marginal velocity field, the quantum correlation effects in a strong-field double-electron system are quantitatively separated and visually output.

The application provides an antenna unit with low harmonic radiation, comprising a first filter circuit arranged between an energy transmitting ring of an antenna and a BTM, for low-pass filtering of a BTM cable transmission signal, so as to reduce harmonic radiation of the energy transmitting ring. The antenna unit of the application can reduce harmonic components on the BTM main signal, so as to reduce harmonic radiation emission of the antenna on the main signal path, and improve the matching range of the antenna unit and the BTM.

The invention discloses a reflective harmonic radiation enhancement device and a preparation method thereof, and aims to overcome the defects of low nonlinear harmonic conversion efficiency, weak metal nonlinearity, insufficient concentration of a pure medium light field and the like in the prior art. The device comprises an outer protective layer and an internal F-P cavity, the F-P cavity is composed of a first reflecting layer, a dielectric layer and a second reflecting layer, the first reflecting layer is a super-structure surface with gold nano units arranged periodically, and the dielectric layer adopts an organic polymer PFO film. Double enhancement of a light field is achieved through the synergistic effect of local surface plasmon resonance and F-P cavity mode resonance, and the third harmonic conversion efficiency is improved by more than two orders of magnitude compared with a single nonlinear film in combination with the high third-order nonlinear coefficient of PFO. The preparation method adopts the processes of electron beam exposure, evaporation, spin coating and the like, and is simple in process and high in integration. The device is good in stability and wide in adaptability, the limitation of a single resonance mechanism is effectively broken through, and a reliable solution is provided for nonlinear optical signal regulation and control and integrated device application.

This invention relates to a bright-field and dark-field fusion harmonic microscopy imaging device and method for detecting defects in two-dimensional semiconductor crystals, belonging to the field of optical microscopy imaging technology. The device comprises a laser source system, a harmonic signal excitation system, a bright-field signal detection system, a dark-field signal detection system, and a control and data processing system. This invention uses a dark-field spatial filter to filter out bright-field illumination harmonic signals to collect large-wavelength dark-field radiation harmonic signals, and employs a mode of simultaneous detection and fusion of bright-field and dark-field harmonic microscopic images for crystal defect detection. This invention utilizes the harmonic signal interference effect of crystal defects with different orientations, and displays crystal defects and defect edges as high-contrast images through large-angle harmonic radiation and bright-field and dark-field harmonic image fusion. The beneficial effects of this invention are: improved sensitivity and signal-to-noise ratio in two-dimensional semiconductor crystal defect detection.

A process for the generation of a second harmonic radiation from a fundamental radiation, comprising the following operating steps: providing one or more nonlinear crystals (C) that satisfy the condition of second harmonic generation (SHG) through noncritical phase matching; providing an optical phase actuator (A), positioned upstream or downstream of said nonlinear crystal (C) with respect to the main optical axis (O) of the nonlinear crystal, a step of varying one or more of said parameters of the optical actuator (A) over time by controlling the temperature of the optical actuator (A) itself, or by applying electric or magnetic fields to said optical actuator (A), determining said parameters of the optical actuator (A) for which said measured power is maximum with respect to the power measured during said plurality of measurements performed.

The application discloses a communication analysis processing method and device based on a dual-mode heterogeneous communication network fusion, relates to the technical field of communication processing, and comprises the following steps: acquiring real-time running data of HPLC and HRF in a fusion communication system, generating a coupling feature vector, and predicting disturbed frequency points and time periods of the future HRF by using a short-time prediction model; screening a clean frequency band candidate set based on the prediction result, calculating the coupling strength index and the adjacent interference index of each candidate frequency band, and obtaining a candidate front value; selecting a frequency band with the maximum candidate front value as a target communication frequency band in a future preset time window, and concentrating HRF links to the frequency band before interference occurs, which can predict the cross-medium interference that may occur in the future in advance, thereby actively avoiding potential influences before the interference occurs, effectively reducing the risk of data error codes, link interruption and switching delay caused by HPLC harmonic radiation to the HRF communication frequency band, and improving the continuity and reliability of communication.

This invention provides a BTM enhanced antenna unit, including a first filtering circuit, a power supply and triggering circuit, a logic control unit, and a signal acquisition and decision circuit. The first filtering circuit is disposed between the power transmission loop of the antenna and the BTM, and is used to reduce harmonic radiation of the power transmission loop. One end of the power supply and triggering circuit is connected to the power receiving loop, and the other end is connected to the logic control unit, used to regulate the electrical signal on the BTM cable and output a trigger signal to the logic control unit. The signal acquisition and decision circuit is used to acquire the A4 interface signal, make a decision on the A4 interface signal, and output the decision result to the logic control unit. The logic control unit is used to control the acquisition and transmission of the A4 interface signal according to the trigger signal and the decision result. The BTM antenna unit of this invention has an energy judgment function, which improves the reliability of the BTM antenna, reduces the harmonic radiation of the BTM signal, and improves the compatibility between the antenna unit and the BTM.

A method for treating near-retina floaters includes dilating a pupil of an eye of a patient to at least 6.6 millimeters (mm). While the pupil is dilated to at least 6.6 mm, the method further includes emitting, by an optical delivery system, a plurality of pulses from a treatment laser into the eye of the patient, each pulse of the plurality of pulses having a diameter upon passing through the pupil that substantially fills the pupil and having a focus within 3 mm of a retina of the eye of the patient. Pulses may pass through adaptive optics that may be adjusted based on light emitted from the eye, such as two-photon fluorescence or second harmonic radiation, in order to reduce spot size at the focus.

The application discloses a kind of phase perfect matching high-efficiency second harmonic generation efficiency nonlinear optical structure, including fundamental wave resonant structure, nonlinear optical layer, second harmonic reflection structure and substrate;Fundamental wave resonant structure is used to generate electromagnetic field local enhancement at incident fundamental wavelength, and phase matching condition is realized by optimizing electric field phase distribution;Nonlinear optical layer is used for frequency conversion of fundamental wave to second harmonic, and harmonic radiation capacity and phase control are regulated;Second harmonic reflection structure is used to control the coupling-out of second harmonic;Rotating nonlinear optical layer can adjust the phase characteristics of radiated second harmonic, to realize the phase perfect matching of harmonic field;The phase perfect matching high-efficiency second harmonic generation efficiency nonlinear optical structure realizes the accurate control of phase matching condition by reasonable optical thin film stack and phase matching technology, ensures the efficient coupling-out and utilization of second harmonic.

The invention discloses a light source device, a light source system and a water window wave band full-coherence free electron laser generation method. The device comprises a harmonic generation unit used for accessing an electron beam and seed laser and generating low-order harmonics; and the at least two stages of cascaded amplifier units are connected with the harmonic generation unit, and are used for accessing low-order harmonic radiation, generating coherent harmonic radiation and tuning the coherent harmonic laser into high-order harmonic radiation so as to obtain the water window wave band full-coherent free electron laser pulse. According to the invention, the multi-stage amplifier units are constructed at the rear stage of the harmonic generation unit, and each subsequent amplifier unit is configured to resonate on a higher harmonic output and radiated by the previous amplifier unit, so that the harmonic radiation of the previous stage is used as an effective seed of the next stage, and the step-by-step up-conversion of the frequency is realized; and converting the frequency of the coherent radiation to a target higher harmonic step by step to obtain the water window wave band full-coherent free electron laser.