MikroBolometerArrays

MikroBolometerArrays are uncooled infrared detector arrays used for thermal imaging. Each pixel contains a microbolometer, a micromachined thermistor that absorbs infrared radiation and changes its electrical resistance as its temperature changes. The resistance variation is read by a readout integrated circuit, typically a CMOS ROIC, and converted into a digital image. The technology enables imaging in the long-wave infrared region without cryogenic cooling.

The array is fabricated on a silicon substrate with suspended microstructures and receives infrared radiation that heats the microbolometer film. Common detector materials include vanadium oxide (VOx) and amorphous silicon (a-Si). Pixel pitches commonly range from about 12 to 25 micrometers, and formats span from VGA (640x480) to higher resolutions such as 1280x960 or more. The spectral response is typically in the 8–14 micrometer band, suitable for room-temperature scene imaging. Operation is passive and compact, making devices smaller and less costly than cooled infrared cameras.

Performance depends on materials, readout electronics, and optics. NETD values are commonly tens of millikelvin to a few hundred millikelvin, influenced by temperature stability, optical design, and calibration. Frame rates range from tens to hundreds of frames per second. Fixed-pattern noise is mitigated through on-chip nonuniformity correction and software processing, with ongoing improvements in calibration algorithms and materials.

Applications span surveillance, security, industrial inspection, building diagnostics, automotive night vision, and consumer thermal imaging devices. MikroBolometerArrays offer advantages in cost, size, and simplicity due to uncooled operation, though they generally trade some sensitivity and speed for these benefits. The technology has matured since the 1990s and continues to advance with higher-resolution formats and improved detector materials.