Ads
related to: pyroelectric sensor circuit
Search results
Results From The WOW.Com Content Network
Internals of a pyroelectric sensor. Pyroelectricity (from Greek: pyr (πυρ), "fire" and electricity) is a property of certain crystals which are naturally electrically polarized and as a result contain large electric fields. [1] Pyroelectricity can be described as the ability of certain materials to generate a temporary voltage when they are ...
Due to the unipolar axis characteristics of the pyroelectric crystal, it is characterized by asymmetry. Polarization due to changes in temperature, the so-called pyroelectric effect, is currently widely used in sensor technology. Pyroelectric crystals need to be very thin to prepare and are plated in a direction perpendicular to the polar axis.
Being pyroelectric, this material develops a voltage difference across two of its faces under changing temperature conditions; consequently, lead zirconate titanate can be used as a heat sensor. [5] Lead zirconate titanate is also ferroelectric , which means that it has a spontaneous electric polarization ( electric dipole ) that can be ...
A pyroelectric nanogenerator is an energy-harvesting device that converts external thermal energy into electrical energy by using nano-structured pyroelectric materials. The pyroelectric effect is about the spontaneous polarization in certain anisotropic solids as a result of temperature fluctuation. [ 61 ]
Pyroelectric detectors detect photons through the heat they generate and the subsequent voltage generated in pyroelectric materials. Thermopiles detect electromagnetic radiation through heat, then generating a voltage in thermocouples .
Golay cells follow thermal expansion. In IR spectrometers the pyroelectric detectors are the most widespread. The response time and sensitivity of photonic detectors can be much higher, but usually these have to be cooled to cut thermal noise. The materials in these are semiconductors with narrow band gaps. Incident IR photons can cause ...
Occupancy sensor types include: PIR sensors, which work on heat difference detection, measuring infrared radiation.Inside the device is a pyroelectric sensor which can detect the sudden presence of objects (such as humans) who radiate a temperature different from the temperature of the background, such as the room temperature of a wall.
Language links are at the top of the page across from the title.