Photoflash filter

Claim 1

Illumination apparatus for use in photography comprising: a photoflash lamp which emits radiant energy having a distribution of wavelengths ranging from less than 400 nm to greater than 700 nm; a filter element associated with said photoflash lamp for filtering out the photographically superfluous radiation emitted by said photoflash lamp, said filter element comprising at least one material providing a maximum absorption of infrared radiation of wavelengths greater than 700 nm while providing maximum transmission of radiation in the visible region of the spectrum; said filter element being fabricated from an organic plastomeric material which is substantially transparent to radiation in said visible region, said filter element including either (a) the combination of 1,4,5,8-tetrakismethyl-amino-anthraquinone together with 1,4-bis(sec-buty) amino-anthraquinone or (b) the combination of 1,4,5,8-tetrakismethylamino-anthraquinone together with a dithio-metal complex of the formula: ##SPC4## wherein Me is Ni or Pt; and all R's represent the same substituted or unsubstituted phenyl group; said filter element absorbing at least 10% of the total radiation having wavelengths between 700 nm and 2,000 nm.