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A mercury-vapor lamp excites Mercury atoms in an electrical discharge and collects the light emitted as they relax. Its output contains characteristic spectral lines; the lamp's pressure and construction affect their widths and the balance between lines and background.

A spectroscope separates those lines, making the lamp useful for wavelength references and optical excitation. Some emitted ultraviolet radiation can excite a phosphor, which converts it into a broader visible output. The observed spectrum then depends on the discharge, envelope transmission and any conversion coating; it is not simply the isolated-atom spectrum at every operating condition.

A surface ionization detector detects a neutral atomic beam by converting incident chemical atoms into ions on a hot surface. For suitable alkali metals, a heated tungsten surface can favor loss of an electron: the competing surface work function and atomic ionization energy make the efficiency strongly dependent on species, surface condition and temperature. An electric field then collects the resulting ions, producing an electric current or a count after amplification. A response therefore requires an efficiency measurement calibration; it is not automatically equal to the incident particle flux.

A 2002 imaging experiment used a tungsten-coated heated ribbon followed by a microchannel plate detector and a phosphor screen. It recorded where the arriving neutral chemical atoms struck, rather than just their total rate. The reported approximately $20\mu \mathrm{m}$ spatial resolution and roughly $50\%$ detection efficiency belong to that apparatus and its conditions, rather than to every surface ionization detector.^[ref]

An additive color display mixes separate red, green and blue emitters. A phosphor-converted white light-emitting diode converts some blue photons to longer-wavelength light in a phosphor, mixing it with unconverted blue to produce perceived white. Hiroshi Amano distinguishes display and phosphor-lighting applications.^[ref]