Читать книгу Ferroic Materials for Smart Systems - Jiyan Dai - Страница 13

An infrared sensor is usually made of a ferroelectric material, which is also pyroelectric that generates surface electric charges when exposed to heat in the form of infrared radiation. A pyroelectric‐based infrared sensor can detect the temperature change but produce no response for a steady temperature since the pyroelectric sensing element can only produce polarization change‐induced electric charge when the sensor is subject to temperature change. Figure 1.9a shows a photo of a real infrared detector with its internal device structure illustrated in Figure 1.9b, where the active element is made of pyroelectric materials such as LiTaO₃. Those pyroelectric materials with their polarization able to be switched are ferroelectrics. Therefore, pyroelectric sensors that are widely used as infrared detectors are important device applications for ferroic materials in a smart system.

Figure 1.9 A photo of an infrared detector (a) and illustration of its internal structure (b).