Analysis of 320X240 uncooled microbolometer focal plane array ...

Figure 4.2 A single thermoelectric element being bias by a DC source [111The thermoelectric cooler essentially works in a similar fashion. Instead ofrefrigerant, electrons are used in case of the TEC (see Figure 4.2). At the cold side ofTEC, energy (heat) is absorbed as electrons passes from a lower energy level of p-typematerial to a higher energy level of n-type material. At the hot side, the situation isreversed. Heat is emitted to the environment as electrons move from n-type high energylevel to p-type low energy level. As shown in Figure 4.3, p-type and n-typesemiconductor couples are placed electrically in series and thermally in parallel to makethe device more effective.