UVdetectors

UV detectors are instruments that sense electromagnetic radiation in the ultraviolet (UV) portion of the spectrum, typically defined as wavelengths from about 10 nm to 400 nm. They convert incident UV photons into electrical signals using a variety of physical effects, and are chosen based on spectral range, sensitivity, speed, noise, and environmental durability.

Common types include semiconductor photodiodes (silicon, GaN, AlGaN), photomultiplier tubes (PMTs), avalanche photodiodes (APDs), microchannel plate detectors, and CMOS or CCD imagers with UV-sensitive coatings. Photoconductors and scintillator-coupled detectors are used where direct semiconductor detection is impractical. Solar-blind detectors, using materials such as AlGaN or diamond, are designed to be insensitive to wavelengths longer than about 280–300 nm to avoid background from sunlight.

Performance metrics include responsivity, quantum efficiency, spectral responsivity, dark current, noise-equivalent power, and response time. Optical elements (filters, gratings, lenses) and window materials (fused silica, MgF2, CaF2) are important for defining the usable UV band and rejecting visible/IR light. Calibration and environmental factors such as temperature, ozone absorption, contamination, and vacuum requirements affect accuracy and longevity.

Applications span astronomy and space science, flame and corona detection, environmental monitoring of ozone and UV index, spectroscopy and chemical analysis, semiconductor lithography, and biological fluorescence assays. Design trade-offs balance sensitivity, spectral selectivity, size, cost, and operational environment.