The disclosed embodiments are generally directed to optical systems. The optical systems may include a proximal lens that may transmit light toward an eye of a user. The optical systems may also include a distal lens that may, in combination with the proximal lens, correct for at least a portion of a refractive error of the eye of the user. The optical systems may further include a selective transmission interface. The selective transmission interface may couple the proximal lens to the distal lens, transmits light having a selected property, and does not transmit light that does not have the selected property. The optical system can also include an accommodative lens, such as a liquid lens. Various other methods, systems, and computer-readable media are also disclosed.

Provided are a preparation method of a piezoelectric composite material, and the application thereof. The preparation method includes: step 1, designing a curved-surface 3D printed mesh mold and forming the curved-surface 3D printed mesh mold by printing; step 2, cutting a blocky piezoelectric phase into a plurality of small piezoelectric columns; step 3, inserting the small piezoelectric columns into empty cells of the 3D printed mold; step 4, filling gaps between the piezoelectric columns and the 3D printed mold with a non-piezoelectric phase such as an epoxy resin, and curing and forming the non-piezoelectric phase; and step 5, grinding, polishing, and ultrasonically cleaning a prepared sample, and then performing an electrode coating operation on the sample to obtain a curved-surface piezoelectric composite material.

The present invention relates to a piezoelectric fiber having excellent flexibility, the piezoelectric fiber employs a conductive fiber member as an inner electrode, on which a piezoelectric polymer layer, an outer electrode and a coating layer are sequentially formed, thereby having excellent flexibility and sufficient elasticity to be sewed, woven, knotted or braided. Therefore, the piezoelectric fiber can be applied in power supplies for a variety of sizes and types of wearable electronic devices, portable devices, clothing, etc. In addition, since the piezoelectric fiber has excellent piezoelectricity and durability because of the above-described structure, it can effectively convert deformation or vibration caused by external physical force into electric energy, and thus can replace existing ceramic-based and polymer piezoelectric bodies, etc. Furthermore, an economical and simple method of manufacturing a piezoelectric fiber having excellent piezoelectricity is provided.

The present invention is related to a stretchable tubular device (1) comprising at least one layer (Lx) of a stretchable polymer, a power supply (2) and a set of electrodes (3a, 3b) connected to said power supply (2). The power supply can supply at least a first level of voltage (V1) to the electrodes so as to modify the natural force (F0) of the stretchable layers to a modified force (F1). The present invention also covers a process for manufacturing such a tubular device and its use as a medical implant.

The invention relates to aqueous dispersions of fluoropolymers comprising recurring units derived from vinylidene fluoride (VDF) in an amount of from 60% to 82% in moles and recurring units derived from trifluoroethylene (TrFE) in an amount of from 18% to 40% in moles, with respect to the total moles of recurring units, said fluoropolymers possessing an improved thermodynamic ordered structure in the ferroelectric phase.

The invention relates to aqueous dispersions of fluoropolymers comprising recurring units derived from vinylidene fluoride (VDF) in an amount of from 60% to 82% in moles and recurring units derived from trifluoroethylene (TrFE) in an amount of from 18% to 40% in moles, with respect to the total moles of recurring units, said fluoropolymers possessing an improved thermodynamic ordered structure in the ferroelectric phase.

A polymeric piezoelectric film including an optically active helical chiral polymer (A) having a weight average molecular weight of from 50,000 to 1,000,000, wherein: a crystallinity obtained by a DSC method is from 20% to 80%; a standardized molecular orientation MORc measured by a microwave transmission-type molecular orientation meter based on a reference thickness of 50 μm is from 3.5 to 15.0; and in a waveform measured with an inline film thickness meter and representing a relationship between a position in a width direction on the film and a thickness of the film, a number of peaks A is 20 or less per 1,000 mm of a film width, wherein the peaks A have a peak height of 1.5 μm or more and a peak slope of 0.000035 or more.

A method for producing a porous piezoelectric polymer film with a dense surface, includes depositing a polymer solution onto a substrate to form a polymer film including a solvent; evaporating a portion of the solvent to form the dense surface away from the substrate; forming water droplets in interior of the polymer film; and substantially evaporating the water droplets and remaining solvent to form porous interior. A piezoelectric composition includes a piezoelectric material with a porous interior and a dense surface for interfacing with an electrode. A piezoelectric device includes a first electrode; a porous piezoelectric film with a dense surface and porous interior, wherein the porous piezoelectric film is deposited on the first electrode and the dense surface is away from the first electrode; and a second electrode deposited on the dense surface for, together with the first electrode, providing an electrical interface for the porous piezoelectric film.

Provided is a polymeric piezoelectric film including a helical chiral polymer having a weight average molecular weight of from 50,000 to 1,000,000 and having optical activity, in which a crystallinity of the film measured by a DSC method is from 20% to 80%, a product of a standardized molecular orientation MORc measured by a microwave transmission-type molecular orientation meter based on a reference thickness of 50 μm and the crystallinity is from 40 to 700, and, when a refractive index in a slow axis direction in the film surface is n.sub.x, a refractive index in a fast axis direction in the film surface is n.sub.y, a refractive index in a thickness direction of the film is n.sub.z, and an Nz coefficient=(n.sub.x−n.sub.z)/(n.sub.x−n.sub.y), the Nz coefficient is from 1.108 to 1.140.

A transducer device, including an electroactive polymer transducer, which has at least two electrode layers which are situated in parallel to one another and which are connected to one another by inserting an elastic intermediate layer in each case, and including a circuit having electronic components for the purpose of generating an electrical voltage applied to the electrode layers of the polymer transducer, the circuit increasing an input voltage to a voltage which is increased with regard to the input voltage.