Pyroelektriska

Pyroelektriska refers to materials that exhibit pyroelectricity. Pyroelectricity is a property of certain crystalline materials that have a spontaneous electric polarization. This polarization arises from the arrangement of charged ions within the crystal lattice. When the temperature of a pyroelectric material changes, either by heating or cooling, the magnitude of this spontaneous polarization changes. This change in polarization results in the generation of an electric voltage across the material.

The pyroelectric effect is distinct from the piezoelectric effect, although both phenomena are related to the electrical properties of crystalline materials. Piezoelectricity is the generation of an electric charge in response to applied mechanical stress, while pyroelectricity is the generation of an electric charge in response to a change in temperature. In many pyroelectric materials, the pyroelectric effect is a consequence of the piezoelectric effect when subjected to thermal expansion or contraction.

Pyroelectric materials have found applications in various sensing devices. They are used in infrared detectors, motion sensors, and non-contact thermometers. The sensitivity of pyroelectric sensors to temperature fluctuations makes them suitable for detecting thermal radiation. The generated voltage is proportional to the change in temperature, allowing for quantitative measurements. Common pyroelectric materials include lithium tantalate, triglycine sulfate, and polyvinylidene fluoride. The efficiency and properties of pyroelectric sensors depend on the specific material used and the design of the detector.