Patent ID: 7015164
Filing Date: 2006-03-21
Classification: C03C,Y10S

Abstract:
1. An optical glass comprising, expressed as weight percentages, greater than 18.92 percent and less than 30 percent of SiO 2 , greater than or equal to 12 percent and less than 23 percent of BaO, 22 to 37 percent TiO 2 , greater than or equal to 7 percent and less than 16 percent Nb 2 O 5 , 5 to 20 percent of Na 2 O, 0 to 6 percent of K 2 O, 0 to 5 percent of CaO, 0 to 5 percent of SrO, greater than 0 to equal to or less than 4 percent of ZrO 2 , 0 to 3 percent of Ta 2 O 5 , 0 to 1 percent of Sb 2 O 5 , and greater than or equal to 0 percent and less than 0.5 percent of P 2 O 5 , and essentially not comprising PbO, As 2 O 3 , and F; and wherein the weight ratio SiO 2 /TiO 2 of SiO 2 to TiO 2 exceeds 0.86, and the index of refraction (nd) is greater than or equal to 1.84 and the Abbé number (vd) is less than or equal to 25.