Focal Plane Array (FPA)
The so-called Focal Plane array (FPA) is a special type of bolometer and is used as a thermal detector in infrared cameras. The FPA is based on a series of small thin-film bolometers arranged in a matrix in the focal plane of the detector. This results in a planar pixel sensor, allowing an improved price-performance ratio in various applications.
Vanadium oxide (VOX) and amorphous silicon alternative technologies are used as the materials for the thin-film bolometers required. Typical detector sizes today are 160x120, 320x240 and 640x480 pixels. Whilst in the past pixels were generally 35x35 µm in size, these days pixel sizes of 25x25 µm, 17x17 µm or even 12x12 µm are possible. Among other things, the resulting reduction of the detector surface size also results in smaller and lower cost optical systems.