These lampseffciently emit near ultraviolet rays at 315nm-400nm which have strong photochemical flourescent effects.
They are special deep blue fi;ter glass which absorbs visible rays and transmits near ultraviolet rays and two types of hosphor are used with radiation peak at 352 nm and 368 nm, respctively.
They are used for tests, insections, examinationa, and investigations in various fields, as weel as for stage illumination in theaters and nightclubs, advertisements and sign boards.