An electroactive ceramic may be incorporated into a transparent optical element between transparent electrodes and may characterized by a preferred crystallographic orientation. The preferred crystallographic orientation may be aligned along a polar axis of the electroactive ceramic and substantially parallel to each of the electrodes. Optical properties of the optical element, including transmissivity, haze, and clarity may be substantially unchanged during actuation thereof and the attendant application of a voltage to the electroactive ceramic.

The piezoelectric composition is represented by the following Chemical Formula (1):
x[Bi.sub.mFeO.sub.3]-y[Ba.sub.mTiO.sub.3]-z[Sr.sub.mTiO.sub.3](1)
wherein 0.5x0.8, 0.02y0.4, 0.02z0.2, x+y+z=1, and 0.96m1.04.

A method for producing an at least partially transparent device is provided, including producing, on a first substrate, first and second separation layers one against the other; producing, on the second separation layer, an at least partially transparent functional layer; making the functional layer integral with a second at least partially transparent substrate; forming a mechanical separation at an interface between the separation layers; removing the second separation layer; producing a first at least partially transparent electrode layer on the functional layer; where the materials of the stack are chosen such that the interface between the separation layers corresponds to that, among all the interfaces of the stack, having the lowest adherence force.

A magnetoelectric energy harvester having excellent power generation performance and a manufacturing method thereof are provided. The magnetoelectric energy harvester includes a magnetostrictive material portion including a magnetostrictive material which generates a mechanical deformation when being magnetized. The magnetoelectric energy harvester also includes a piezoelectric material portion which has a bending vibration mode and includes a piezoelectric material which produces power by receiving a mechanical deformation force from the magnetostrictive material portion.

A method of imaging infrared light is provided which comprises: exciting ultrasonic waves in a metal pillar (e.g., Cu pillar); measuring the Time-of-Flight (ToF) of the ultrasonic wave in the waveguide; whereas the ToF is a function of incident Infrared light energy on the waveguide, and reporting the infrared light energy to capture an image. An apparatus of imaging infrared light is provided which comprises: a transducer; a waveguide coupled with the transducer; and a pixel electronic circuit coupled to the transducer, wherein the transducer includes one or more of: PZT, LiNb, AlN, or GaN.

A piezoelectric composition comprises a plurality of crystal particles, wherein the piezoelectric composition includes bismuth, iron, barium, titanium, and oxygen; the crystal particles include a core and a shell covering the core; the average value of the contents of bismuth in the cores is expressed as C.sub.CORE % by mass, the average value of the contents of bismuth in the shells is expressed as C.sub.SHELL % by mass, and the C.sub.CORE is lower than the C.sub.SHELL; and the number of all the particles comprised in the piezoelectric composition is expressed as N, the number of the crystal particles including the core and the shell is expressed as n, and n/N is 0.10 to 1.00.

A piezoelectric ceramic, which does not contain lead as a constituent element, is characterized in that: its primary component is a perovskite compound expressed by the composition formula (Bi.sub.0.5x/2Na.sub.0.5x/2Ba.sub.x)(Ti.sub.1yMn.sub.y)O.sub.3 (where 0.01x0.25, 0.001y0.020); and the coefficient of variation (CV) in grain size among the grains contained therein is 35 percent or lower. The piezoelectric ceramic presents an improved dielectric loss tangent tan .

A piezoelectric element includes first and second electrodes, a first piezoelectric body layer, and a plurality of first through-hole conductors. The first and second electrodes oppose each other. The first piezoelectric body layer is disposed between the first electrode and the second electrode. The plurality of first through-hole conductors penetrates the first piezoelectric body layer and is connected to the first electrode and the second electrode. When seen in an opposing direction of the first and second electrodes, the plurality of first through-hole conductors is arrayed in a matrix.

A piezoelectric composition comprises an oxide having a perovskite structure, wherein the oxide contains bismuth, barium, iron and titanium; the X-ray diffraction pattern of the piezoelectric composition after a polarization treatment has a first peak and a second peak in the range of the diffraction angle 2 of 38.6 or more and 39.6 or less; the diffraction angle 2 of the first peak is smaller than the diffraction angle 2 of the second peak; an intensity of the first peak is represented as I.sub.L; an intensity of the second peak is represented as I.sub.H; and I.sub.H/I.sub.L is 0.00 or more and 2.00 or less.

A piezoelectric thin film 3 contains a metal oxide, the metal oxide contains bismuth, potassium, titanium, iron and element M, the element M is at least one of magnesium and nickel, at least a part of the metal oxide is a crystal having a perovskite structure, and a (001) plane, a (110) plane or a (111) plane of the crystal is oriented in a normal direction dn of the surface of the piezoelectric thin film 3.