Ultraviolet photography sensor will pick up reflected infrared radiation as well as ultraviolet, which may obscure the details that would be resolved by ultraviolet alone. Most types of glass will allow longwave UV to pass, but absorb all the other UV wavelengths, usually from about 350 nm and below. For UV photography it is necessary to use specially developed lenses having elements made from fused quartz or quartz and fluorite. Lenses based purely on quartz show a distinct focus shift between visible and UV light, whereas the fluorite/quartz lenses can be fully corrected between visible and ultraviolet light without focus shift. Examples
Ultraviolet photoelectron spectroscopy seen a considerable revival with the increasing availability of synchrotron light sources which provide a wide range of monochromatic photon energies. Ultraviolet photoelectron spectroscopy Ultraviolet photoelectron spectroscopy (UPS) refers to the measurement of kinetic energy spectra of photoelectrons emitted by molecules which have absorbed ultraviolet photons, in order to determine molecular orbital energies in the valence region. If Einstein's photoelectric law is applied to a free molecule, the kinetic energy (formula_1) of an emitted photoelectron is given by where "h" is Planck's constant, ν is the frequency of the ionizing light, and I is an ionization energy for the formation