Abstract
SPECIMENS of ultra-violet transmitting plate glass produced by Messrs. Pilkington Brothers Ltd., of St. Helens, Lancashire, show a region of high transmission in the region near 3650 A., with an almost complete opacity to the visible spectrum except in the extreme violet, where the transmission is, however, said to be only about 1 per cent. Tested with a powerful spark source and a monochromator, the claims of the makers were found to be justified. The transmission in the ultra-violet was comparable with that of an ‘ultra-violet’ glass from another source, the cadmium line near 3610 A. being freely transmitted; but whereas Messrs. Pilkington's new glass showed no transmission in the visible region when tested with a pocket spectroscope, the other glass showed a marked transmission band in the red. The glass can be manufactured in large sizes; specimens have been submitted of thickness 8 mm. and 11 mm. respectively. In view of the increasing importance of fluorescence tests, and other applications of ultraviolet radiation, numerous uses should be found for it, since its opacity to visible radiations should facilitate the distinction between genuine fluorescence and effects of reflected light. It may be worth noting that in very thin layers this new glass is of a blue-green colour. A prism of small angle ground to a very thin edge should make a very pretty example of dichromatism.
Article PDF
Rights and permissions
About this article
Cite this article
Ultra-Violet Transmitting Glass. Nature 136, 60 (1935). https://doi.org/10.1038/136060b0
Issue Date:
DOI: https://doi.org/10.1038/136060b0