Optical glass, press-molding glass material, optical element and method of manufacturing the same, and bonded optical element

An optical glass, which comprises, denoted as weight percent,

• 2 to 37 percent of SiO2,
• 0 to 25 percent of B2O3,
• 0 to 10 percent of GeO2,
• 18 to 55 percent of a combined content of Li2O, Na2O, K2O, CaO, SrO, and BaO, and
• 27 to 55 percent of a combined content of TiO2, Nb2O5, and WO3;
• as well as comprises no La2O3;
• wherein the weight ratio of SiO2 content relative to a combined content of SiO2 and B2O3 (SiO2/(SiO2+B2O3) ranges from 0.1 to 1;
• a weight ratio of the Li2O content to a combined content of Li2O, Na2O, K2O, CaO, SrO, and BaO (Li2O/(Li2O+Na2O+K2O+CaO+SrO+BaO) ranges from 0 to 0.4;
• and
• a weight ratio of TiO2 content relative to a combined content of TiO2, Nb2O5, and WO3 (TiO2/(TiO2+Nb2O5+WO3) ranges from 0.35 to 1;
• and
• which has a refractive index nd ranging from 1.860 to 1.990 and an Abbé number νd ranging from 21 to 29.