Patent ID: 8835334
Filing Date: 2014-09-16
Classification: C03C

Abstract:
1. An optical glass having a refractive index nd of 2.0 or more, an Abbe's number νd of 20 or less, a glass transition point of 450° C. or below, and a glass composition, in % by mass, of 70 to 90% Bi 2 O 3 , 4 to 29.9% B 2 O 3 , 0.1 to 10% Li 2 O+Na 2 O+K 2 O, 0 to 2% SiO 2 , and 0 to 2.5% SiO 2 +Al 2 O 3 and being substantially free of lead component, arsenic component, F component, TeO 2 , and GeO 2 .