Society of Glass Technology · [Sheffield] · leaf 152
the aSi02,6CaO,cR20 type, where(a+ 6 + c) = 100 per cent., b is increased to (6 + 1) per cent., the risein refractive index is the same whether R20 is represented by Na,0or K20, granted that the percentage difference is spread equallyover the other two constituents, This rise in ?jD is 0-0024. B?… … 1000 900 15 Percentage R20.Fig. 10. 20 li) 15 Percentage R20.Fig. 11. The rise in total dispersion is 0-00005 when the glass containsNa20 and 0-00006 when K20 is the alkali oxide. (9) Fig. 10 shows diagrammatically the increase in nB due toincreasing the alkali oxide, the CaO being the constant…
Glass
Internet Archive · Gerstein Library, University of Toronto · Public Domain Mark 1.0. Free to use for anything.
