33 results about "Coherent control" patented technology

A method and system are presented for producing an output coherent anti-stokes Raman scattering (CARS) signal of a medium. The method comprises generation of a unitary optical excitation pulse that carries a pump photon, a Stokes photon and a probe photon; and inducing a CARS process in the medium by exciting the medium by the at least one such unitary optical excitation pulse.

A method and system (10) are presented for producing exciting radiation (P′) to be used in producing an output coherent anti-stokes Raman scattering (CARS) signal of a medium (12). An input spectral phase coherent optical pulse (P), carrying a pump, a Stokes and a probe photon, is optically processed by adjusting spectral phase and polarization of wavelength components of the input pulse to produce a unitary optical exciting pulse (P′) that carries the pump photon, the Stokes photon and multiple probe photons and is capable of inducing interference between contributions from at least some of vibrational levels in the CARS signal.

The invention provides a coherent control array structure of micro lens integrated VCSELs (Vertical-Cavity Surface-Emitting Lasers), which belongs to the technical field of semiconductor optical electronics and aims at increasing the coherence degree of the existing high-power VCSEL light beam. The coherent control array structure of the micro lens integrated VCSELs, provided by the invention, comprises multiple micro lens integrated VCSELs, wherein each micro lens integrated VCSEL is formed by an n-surface electrode, a substrate, a buffer layer, an n-type DBR (Distributed Bragg Reflector) layer, an active area, an oxidation limit layer, a p-type DBR layer, an ohm contact layer and a metal grid electrode from top to bottom, the upper surface of the substrate is corroded into a micro lens, and a passivating layer is arranged from the active area down to two sides of the metal grid electrode. The coherent control array structure provided by the invention is a high-power VCSEL array which is coherently coupled and output between array units, has a good light beam coherence, and has a potential value in application fields such as laser detecting, laser radar imaging, laser processing, laser controlling and laser weapons.

The invention relates to coherent and tunable optical holography. The coherent and tunable optical holography comprises coherent control of an incident polarization state and optical holography of a metamaterial code, wherein polarization standing wave coherent control is incident to the polarization state of a metasurface to dynamically display holographic images under different polarization states, a polarization standing wave is formed by two incident waves which are propagated in opposite directions and of which the polarization states are orthogonal in an interference way, the polarization state incident to the metamaterial is controlled dependent on phase difference, the metamaterial is a structure comprising a substrate and a nanometer unit layer, phase information of an object is coded by changing space distribution of the nanometer unit, so that a phase holographic diagram of the object is formed. The holographic diagrams displayed when light in different polarization states is incident to the metamaterial are different to obtain polarization identification and reproduction of optical holographic images, and dynamic change of the optical holographic images during gradual changing process of the polarization states of the incident light is achieved.

The invention belongs to the field of electromagnetic waves and novel artificial electromagnetic materials, and particularly relates to a dynamic tunable absorber based on coherent control and used for perfect electromagnetic wave absorption. The dynamic tunable absorber based on coherent control is composed of a dielectric layer and artificial electromagnetic material layers, wherein the artificial electromagnetic material layers are located on the two sides of the dielectric layer and are both etched on the substrate of the dielectric layer. Each artificial electromagnetic material layer is of an asymmetrical split ring structure where artificial electromagnetic materials are arranged in a periodic or aperiodic mode, wherein the asymmetrical split ring structure is formed by two metal wires or arcs in different lengths. According to the dynamic tunable absorber, operation is easy, the absorption band of the absorber can be adjusted by regulating and controlling the phase of the wave and the structure, dimension parameters and material attribute of the novel artificial electromagnetic material, and then selective absorption of electromagnetic waves in a specific frequency can be achieved. The dynamic tunable absorber also has the advantages of being portable, light, easy to integrate and the like.

A magnetic resonance imaging apparatus includes a data acquisition unit and an image data generating unit. The data acquisition unit acquires data according to a sequence derived by adding a coherent control pulse on a Steady-State Free Precession pulse sequence for repeating plural radio frequency excitations with a constant interval. The coherent control pulse has a center at a substantially center time between adjacent radio frequency excitations and a zero-order moment of which amount is zero. The image data generating unit generates image data based on the data.

The invention belongs to the field of electromagnetic wave and novel artificial electromagnetic materials and particularly relates to a dynamically tunable broadband polarization converter, comprising a dielectric layer and a novel artificial electromagnetic material layer. The novel artificial electromagnetic material layer is located on the surface of the dielectric layer, wherein novel artificial electromagnetic material is square diagonal split rings arranged periodically, and the novel artificial electromagnetic material is of sub-wavelength structure; dynamical tunability is based on the principle of coherent control and is finished through two coherent waves, namely a signal wave and a control wave, the two waves have the same amplitude and wavelength and propagate face to face in a direction perpendicular to the novel artificial electromagnetic material, and a phase difference between the signal wave and the control wave is changed. The converter has the advantages of portability, light weight, ease of integration and the like and is of single layer, small thickness, light weight and conformal proneness when compared with a traditional polarization conversion material.

The invention relates to a multi-chain lath laser coherence control common-aperture polarization synthesis method. The method is based on a master oscillator power amplifier (MOPA) structure, the wavefront of each path of amplified light beams is purified by a unit beam purification system, and a coherence control common-aperture polarization synthesis technology is utilized to solve the problem that coherence synthesis energy is dispersed to side spots in the prior art, thereby realizing laser output with high mean brightness and common aperture. The multi-chain lath laser coherence control common-aperture polarization synthesis method comprises a unit beam purification technology, a phase-locked technology and a common aperture polarization control technology. A synthesis path can be expanded to multiple paths.

A measurement apparatus includes a beam splitter that splits light from a light source into measurement light to be directed to an object to be measured and reference light to be directed to a reference surface, a beam combiner that combines the measurement light reflected by the object and the reference light reflected by the reference surface to generate combined light, and obtains physical information of the object based on the combined light. The measurement apparatus further includes a coherence controller which changes spatial coherences of the measurement light and the reference light.

An optical fiber chromatic dispersion distribution measuring apparatus for measuring the chromatic dispersion distribution of an optical fiber under test comprising two light sources 1, 2 at least one of which can change wavelength thereof, wherein light beams having different wavelengths from each other and emitted from the two light sources are inputted to the optical fiber under test 7 to measure a four-wave mixing light beam generated by interaction between the two light beams by optical time domain reflectometer (OTDR) 9; wherein an optical bandpass filter 8 having a fixed center wavelength is provided at a previous stage of the optical time domain reflectometer (OTDR); and wherein a coherence controller 10 for controlling coherence of at least one of the light beams outputted from the two light sources 1, 2.

The invention relates to a nanosecond chirped pulse light producing technology, in particular to a nanosecond chirped pulse light source producing device and method. The problem that existing nanosecond chirped pulse light cannot block atomic inelastic collision and conducts coherent control on atoms is solved. The nanosecond chirped pulse light source producing device comprises a master laser device, a signal generator, a slave laser device, a reference light laser device, a TeO2 crystal, a photoelectric detector, an oscilloscope, a second polarized beam splitting prism, an optical fiber coupling head and an optical fiber, wherein a light path formed by sequentially connecting a first reflecting mirror and a first polarized beam splitting prism in series is arranged between the output end of the master laser device and the input end of the slave laser device, the first polarized beam splitting prism is arranged between the output end of the slave laser device and the input end of the TeO2 crystal, and a light path formed by sequentially connecting a second reflecting mirror and a second half wavelength plate in series is arranged between the output end of the TeO2 crystal and the input end of the second polarized beam splitting prism. The nanosecond chirped pulse light source producing device and method is suitable for nanosecond chirped pulse light production.

The invention relates to an atomic interference gyroscope signal resolving method and device, computer equipment and a storage medium, and is suitable for the technical field of precise instruments, and the method comprises the steps: carrying out the frequency modulation of coherent control laser, and obtaining modulated laser; carrying out coherent manipulation on an atomic beam by utilizing the modulated coherent manipulation laser, so that the atomic beam interferes with each other; obtaining interference fringes formed after interference of the atomic beam, and calculating an envelope center point of the interference fringes; and calculating the rotation angular rate based on the modulation frequency corresponding to the envelope center point. By adopting the method, the rotation angular rate of the atomic interference gyroscope can be accurately and effectively calculated, and the measurement in a large dynamic range can be achieved.

A system and method for providing low interaural coherence at low frequencies is disclosed. In some embodiments, the system may include a reverberator and a low-frequency interaural coherence control system. The reverberator may include two sets of comb filters, one for the left ear output signal and one for the right ear output signal. The low-frequency interaural coherence control system can include a plurality of sections, each section can be configured to control a certain frequency range of the signals that propagate through the given section. The sections may include a left high-frequency section for the left ear output signal and a right high-frequency section for the right ear output signal. The sections may also include a shared low-frequency section that can output signals to be combined by combiners of the left and right high-frequency sections.