What are pyroelectric detectors anyway?
Pyroelectric detectors are thermal detectors. That is, they produce a signal in response to a change in their temperature. Below a temperature Tc known as the Curie point, ferroelectric materials such as TGS or Lithium Tantalate, exhibit a large spontaneous electrical polarisation. If the temperature of such a material is altered, for example, by incident radiation, the polarisation changes. This change in polarisation may be observed as an electrical signal if electrodes are placed on opposite faces of a thin slice of the material to form a capacitor. When the polarisation changes, the charges induced in the electrodes can be made to produce a voltage across the slice if a the external impedance is comparatively high. The sensor will only produce an electrical output signal when the temperature changes; that is, when the level of incident radiation changes. This process is independent of the wavelength of the incident radiation and hence pyroelectric sensors have a flat response over
Related Questions
- Is it useful to cool down pyroelectric detectors for example by using a Peltier device to improve the signal-to-noise-ratio?
- Are InfraTecs pyroelectric detectors and their production process in accordance with RoHS, WEEE and REACH?
- What are the meanings "microphonic effect" or "acceleration response" as used for pyroelectric detectors?"
