midUV

MidUV refers to the middle portion of the ultraviolet spectrum, typically defined as roughly 200 to 320 nanometers. This region lies between the near-UV and the deep-UV, though exact boundaries vary by discipline. The mid-UV is characterized by higher photon energy than visible light and often exhibits strong absorption by many organic compounds, making it valuable for analytical applications, while also presenting challenges for materials and optics.

Light sources used to study mid-UV include broadband emitters such as deuterium lamps and xenon arc lamps, as well as more specialized tunable lasers and synchrotron radiation that provide high flux and spectral control in the 200–320 nm range. Detectors for mid-UV measurements include UV-enhanced photomultiplier tubes, UV-sensitive CCDs, and various photodiodes, with optics and windows made from materials such as quartz, calcium fluoride, and magnesium fluoride to transmit effectively in this range.

Applications of mid-UV science cover spectroscopy, photochemistry, and materials analysis. In chemistry and biochemistry, absorption features in the mid-UV help characterize conjugated systems, proteins, and nucleic acids, sometimes in complement to higher-wavelength measurements. In materials science and photography, mid-UV techniques support surface analysis and lithography processes that rely on shorter wavelengths. In astronomy, space-based observations exploit mid-UV capabilities to study hot stars and the interstellar medium, where Earth’s atmosphere blocks much of this radiation.

Safety considerations are important because UV exposure risks include eye and skin damage, and many mid-UV optics require careful shielding and material handling. Overall, mid-UV provides access to spectral information not available in the visible range, while demanding specialized equipment and practices.