Abstract: A metalens is provided, the metalens includes: a substrate, a plurality of structural units arranged in periodicity; and the structural units are perpendicular to the substrate; the metalens includes a plurality of phase-modulation regions, and each phase-modulation region includes the plurality of structural units; where, each structural unit includes m phase-modulation layers, m?2, so as to make each structural unit in each phase-modulation region provide any phase within the interval of [0,2?] and each phase-modulation region cover the phases within the interval of [0,2?] at a working waveband.

Abstract: A pixel structure is provided, and the pixel structure includes a plurality of phase change units, and the plurality of phase change units are in identical; the plurality of phase change units are arranged in an array; each phase change unit includes an excitation element and a phase change element, and the excitation element is used for applying independent excitation to the phase change element to change a phase state of the phase change element; each phase change element comprises at least one nanostructure made of a phase change material; the phase state of the phase change element includes a crystalline state or an amorphous state; the phase change state of the pixel structure is related to the number of phase change units containing different phase change states.

Abstract: A system of a tunable metasurface is provided, and the system of a tunable metasurface includes: a wavefront modulator, an optical focusing device, a metasurface; the metasurface includes a plurality of nanostructures made of a phase change material, and a phase change state of the phase change material comprises a crystalline state and an amorphous state; the wavefront modulator is set on a side of the optical focusing device that is far away from the metasurface; and the wavefront modulator is used to modulate a wavefront aberration of incident control lights and emit the control lights after wavefront modulated towards the optical focusing device; the optical focusing device is used to focus wavefront-modulated control lights to form a plurality of focal points; the metasurface is set on a focal plane formed by the plurality of focal points.

Abstract: An optical system and an optical camera working at a far-infrared waveband are provided, the optical system along the optical axis from the objection side to the image side includes: a metalens and a spherical lens; the metalens is configured to correct higher-order residual wavefront aberrations; the spherical lens is configured to correct lower-order primary wavefront aberrations; the metalens and the spherical lens are configured to correct aberrations; an absolute value of the curvature radius of an objection-side surface towards the objection side for the spherical lens is greater than an absolute value of the curvature radius of an image-side surface towards the image side for the spherical lens; the optical system satisfies the following condition: 0.83?f/D?0.92; where f is an effective focal length of the optical system, and D is the entrance pupil diameter of the optical system.

Abstract: A design method for a metalens, a metalens, a shaping and beam-combination device and a display device are provided, when Gaussian beams passes through the metalens, the Gaussian beams are shaped into a plurality of flat-topped beams that project to a target position on a target plane. The method includes: determining an incident parameter, and the incident parameter includes wavelengths and radius of the plurality of Gaussian beams; determining an outgoing parameter, and the outgoing parameter includes a width of flat-topped beams; setting metalens portions on the metalens and determining a position of each metalens portion; the metalens portions and the Gaussian beams are one-to-one correspondence, calculating a modulation phase distribution according to the incident parameter, and the outgoing parameter and the position of each metalens portion; arranging unit cells on the metalens portions according to the modulation phase distribution, and obtaining the metalens.

Abstract: A method for designing a metalens used for an image sensor and an image sensor is provided, the method includes: S1. determining a target waveband; S2. according to the target waveband, determining an initial structure parameter and an initial material parameter of the unit cells; S3. optimizing the initial structure parameters of the unit cells and the initial material parameters of the unit cells, so as to obtain target parameters of unit cells; the target parameters of unit cells comprise: a phase of the unit cells and transmittance of the unit cells for an oblique incident light; S4: determining whether the transmittance of the metalens with the target structure parameter of unit cells meets the target transmittance.

Abstract: A battery pack cooling system includes at least a cooling fluid including a plurality of cooling fluid circulation pipelines and at least an electronic water pump, a refrigeration element, a heat exchange element, a thermal runaway sensing element, and a fluid diversion assembly. The electronic water pump is configured to be communicatively connected to a controller of a vehicle and is arranged on the pipelines. the refrigeration element communicates with the cooling fluid circulation pipelines. the heat exchange element communicates with the pipelines. The thermal runaway sensing element is configured to be communicatively connected to the controller. The fluid diversion assembly includes a fluid guide channel and a fluid diversion valve. The fluid diversion valve is set as a multi-way solenoid valve, and has at least two interfaces configured to communicate with the pipelines, and at least one interface communicating with one end of the fluid guide channel.

Abstract: Provided is a metasurface, a design method, a design device, an electronic device and a fabrication method. An antireflection film is covered on the metasurface; the metasurface includes: a substrate; the substrate includes: a first side; and the first side of the substrate has a plurality of negative nanostructures at different locations, and the depth of the plurality of negative nanostructures is less than the thickness of the substrate; the antireflection film is covered on the surface of the first side of the substrate without the plurality of negative nanostructures.

Abstract: A MTF detection device for wafer-lever optical elements is provided, the MTF detection device for a wafer-level optical element include a luminescent target, a mobile disc, an adjustable bracket, and a detection device. The plurality of luminescent targets are movable along the direction of the light path. The mobile disc is set up with a placing area and the mobile disc is movable, so as to locate different locations of the placing area on the extension of the central line of the luminescent target by moving the mobile disc. The distance between the adjustable bracket and the luminescent target is adjustable, and an external processing assembly is located on a first side of the adjustable bracket. The detection device is installed over the adjustable bracket, and is used to receive the light emitted from the luminescent target through the sample to be detected and the external processing assembly.

Abstract: A lens for ToF is provided, the lens includes: an optical system and a lens barrel; and the optical system is confined within the lens barrel. The optical system includes: an aperture slot, an optical filter, and a metalens. The aperture slot, the optical filter and the metalens are disposed sequentially from the object side to the image side, and the total track length of the optical system is less than or equal to 3.1 mm.

Abstract: A method for providing an enhanced estimate of reference barometric pressure. The method uses multiple, dissimilar pressure references, such as in airport weather stations, personal weather stations, and wireless terminals such as smartphones, in order to provide the enhanced estimate of reference barometric pressure. The method generates an enhanced estimate of reference barometric pressure based on a first estimate of reference barometric pressure from a first pressure reference network made up of airport weather stations, for example. The method also uses a second estimate of reference barometric pressure from a second pressure reference network made of up personal weather stations, for example, and a third estimate of reference barometric pressure, also from the second network. The first, second, and third estimates of reference barometric pressure are combined such that both measurement accuracy and timeliness are improved in the resulting, enhanced estimate.

Abstract: Printable inks based on a 2D semiconductor, such as MoS2, and its applications in fully inkjet-printed optoelectronic devices are disclosed. Specifically, percolating films of MoS2 nanosheets with superlative electrical conductivity (10?2 s m?1) are achieved by tailoring the ink formulation and curing conditions. Based on an ethyl cellulose dispersant, the MoS2 nanosheet ink also offers exceptional viscosity tunability, colloidal stability, and printability on both rigid and flexible substrates. Two distinct classes of photodetectors are fabricated based on the substrate and post-print curing method. While thermal annealing of printed devices on rigid glass substrates leads to a fast photoresponse of 150 ?s, photonically annealed devices on flexible polyimide substrates possess high photoresponsivity exceeding 50 mA/W.

Abstract: A polyfluoroalkoxy resin and a method of preparing the same. The method includes: S1: charging deionized water, an organic solvent, a surfactant, and a chain transfer agent to a polymerization kettle; S2: after heating to a set temperature ranging from 50° C. to 80° C., charging an appropriate amount of polymerization monomer consisting of tetrafluoroethylene and perfluoroalkyl vinyl ether till reaching a set pressure ranging from 0.7 MPa to 1.5 MPa, followed by charging an initiator to start reaction; S3: adding additional polymerization monomer and perfluoroalkyl vinyl ether polymerization promoter, and maintaining the pressure in the polymerization kettle till end of reaction, whereby a polyfluoroalkoxy emulsion is obtained; S4: condensing, washing, and pelleting the polyfluoroalkoxy emulsion from step S3 to obtain the polyfluoroalkoxy resin.

Abstract: A method and a device of designing an optical system, and a storage medium are provided. The method includes: S1. determining an initial structure parameter of the optical system according to a design requirement; S2. optimizing the initial structure parameter according to the ray tracing method, and obtaining a theoretical structure parameter; S3. performing a discretization on a phase of a metalens of the theoretical structure parameter and obtaining a discrete phase; S4. performing an optical field propagation simulation according to the discrete phase, and obtaining an imaging performance index; S5. if the image performance index meets the design requirement, obtaining a target structure parameter; if the image performance index doesn't meet the design requirement, re-optimizing the image performance index and obtaining the target structure parameter.

Abstract: A synthetic method and catalyst for preparing 3-(3-oxo-2-pentyl)cyclopentyl dimethyl malonate are disclosed. The synthetic method uses 2-pentyl-2-cyclopentenone and dimethyl malonate as raw materials, and reacts them in the presence of a catalyst to prepare 3-(3-oxo-2-pentyl)cyclopentyl dimethyl malonate, the catalyst is a basic ionic liquid, the pH value of the basic ionic liquid is greater than or equal to 10, and the catalyst is prepared by a method comprising the steps of: mixing the nitrogen-containing heterocyclic compound with an aliphatic carboxylate or hydroxyl aliphatic carboxylate or fluorophosphate under stirring. The synthetic method is environmentally friendly, stable in reaction and low-cost, and the conversion of 2-pentyl-2-cyclopentenone is significantly improved due to the use of the above-mentioned basic ionic liquid as catalyst.

Abstract: Provided is an athermal metalens, the metalens includes: a substrate and a plurality of nanostructures; the plurality of nanostructures are set on at least one side of the substrate, and are arranged in a periodicity; where a thermal refractive index coefficient of the plurality of nanostructures is less than a reference thermal refractive index coefficient; or each nanostructure is composed of at least two materials, and the product of the thermal refractive index coefficient of the at least two materials is less than 0. Thus, the effective refractive index of the nanostructures is insensitive to the temperature changes, and the reduced imaging performance of the metalens caused by temperature drift is improved.

Abstract: A magnetic tunnel junction is disclosed wherein the reference layer and free layer each comprise one layer having a boron content from 25 to 50 atomic %, and an adjoining second layer with a boron content from 1 to 20 atomic %. One of the first and second layers in each of the free layer and reference layer contacts the tunnel barrier. Each boron containing layer has a thickness of 1 to 10 Angstroms and may include one or more B layers and one or more Co, Fe, CoFe, or CoFeB layers. As a result, migration of non-magnetic metals along crystalline boundaries to the tunnel barrier is prevented, and the MTJ has a low defect count of around 10 ppm while maintaining an acceptable TMR ratio following annealing to temperatures of about 400° C. The boron containing layers are selected from CoB, FeB, CoFeB and alloys thereof including CoFeNiB.

Abstract: A perpendicularly magnetized magnetic tunnel junction (p-MTJ) is disclosed wherein a boron containing free layer (FL) is subjected to a plasma treatment with inert gas, and a natural oxidation (NOX) process to form B2O3 before overlying layers are deposited. A metal layer such as Mg is deposited on the FL as a first step in forming a Hk enhancing layer that increases FL perpendicular magnetic anisotropy, or as a first step in forming a tunnel barrier layer on the FL. One or more anneal steps are essential in assisting B2O3 segregation from the free layer and thereby increasing the FL magnetic moment. A post-oxidation plasma treatment may also be used to partially remove B2O3 proximate to the FL top surface before the metal layer is deposited. Both plasma treatments use low power (<50 Watts) to remove a maximum of 2 Angstroms FL thickness.