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Publication of BE509547ApublicationCriticalpatent/BE509547A/xx
F21V—FUNCTIONAL FEATURES OR DETAILS OF LIGHTING DEVICES OR SYSTEMS THEREOF; STRUCTURAL COMBINATIONS OF LIGHTING DEVICES WITH OTHER ARTICLES, NOT OTHERWISE PROVIDED FOR
F21V9/00—Elements for modifying spectral properties, polarisation or intensity of the light emitted, e.g. filters
F21V9/06—Elements for modifying spectral properties, polarisation or intensity of the light emitted, e.g. filters for filtering out ultraviolet radiation
H—ELECTRICITY
H01—ELECTRIC ELEMENTS
H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
H01J61/00—Gas-discharge or vapour-discharge lamps
H01J61/02—Details
H01J61/38—Devices for influencing the colour or wavelength of the light
H01J61/40—Devices for influencing the colour or wavelength of the light by light filters; by coloured coatings in or on the envelope