35 results about "Invisibility cloak" patented technology

The invention discloses a polydimethylsiloxane / graphene flexible composite film with negative dielectric constant and a preparation method thereof. Mix the precursor and curing agent of polydimethylsiloxane with a non-polar organic solvent and add graphene with a mass fraction of 3% to 4%. The non-polar organic solvent and the mass of the precursor Equal; graphene is evenly dispersed in the solution to form a mixed slurry, take the mixed slurry and pour it on the flat plate, so that the mixed slurry is evenly coated on the surface of the flat plate, after curing treatment and peeled off from the flat plate, polydimethylsiloxane is obtained / Graphene flexible composite film. The thickness of the composite film is 0.1-2 mm. The flexible composite film provided by the invention has a negative dielectric constant, has the characteristics of simple process, low cost and easy large-scale production, and has important application value in the fields of wearable devices, sensors, invisibility cloaks and flexible electronic devices.

The invention discloses a concave-convex curved carpet invisibility cloak and a design method thereof. The concave-convex curved carpet invisibility cloak is composed of M*N metasurface units that are periodically extended and arranged at equal intervals in space. The unit includes a three-layer structure from top to bottom, the first layer is an ultra-thin dielectric plate printed with double-ring metal resonators, the second layer is a resin dielectric layer, and the third layer is an ultra-thin metal plate; is formed on the resin medium layer, and the ultra-thin metal plate is conformally formed at the bottom of the resin medium layer; the resin medium layer is a curved surface structure, which is prepared and processed by 3D printing technology; One side of the ultra-thin dielectric board is printed with double-ring metal resonators by PCB technology, and the other side is fully corroded. The carpet stealth cloak of the present invention can be conformal to a cloaked target with any shape, and can also avoid the edges and corners generated at the splicing position of the existing two-dimensional plane splicing structure from affecting the working performance of the carpet stealth cloak.

A two-dimensional thermal invisibility cloak processing method based on reverse identification and a thermal invisibility cloak, the method comprising: establishing a two-dimensional coordinate system x-y and determining that the area surrounded by the two-dimensional coordinate system is a design area of ​​a two-dimensional thermal invisibility cloak, Solve the governing equation of the dimensionless temperature field based on the boundary conditions to obtain the dimensionless background temperature field of the design area, solve the governing equation of the direct problem based on the boundary conditions to obtain the dimensionless temperature field of the direct problem of the thermal conductivity of the region Z3, and solve the thermal conductivity of the region Z3 Accompany the problem to obtain the Lagrangian multiplier, calculate the derivative of the objective function of the thermal conductivity of the region Z3, the conjugate coefficient, and the iterative direction coefficient of the thermal conductivity of the region Z3, solve the sensitivity problem of the thermal conductivity of the region Z3, and calculate the thermal conductivity of the region Z3 The iterative step of , update the thermal conductivity of zone Z3, and calculate the objective function, if the value is small enough to meet the user's requirements, the thermal conductivity of zone Z3 is processed, otherwise return to the third step.