An optical glass having a high refractive index and high dispersion characteristics
suitable for application to precision press molding to precisely mold final products
without requiring grinding or polishing. An optical glass can be prepared exhibiting
a refractive index in the range of from 1.75 to 2.0, and an Abb number in
the range of from 20 to 28.5. Optical parts comprised of this glass; press-molding
materials comprised of this glass; methods of manufacturing the same; and methods
of manufacturing molded glass products employing these materials. A suitable optical
glass is composed of the following in molar percent: 15-30% P2O5;
0.5-15% B2O3; 5-25% Nb2O5; 6-40% WO3;
4-45% of at least one of Li2O, Na2O or K2O; 1-5%
K2O; 2-9% TiO2; and 0-30% (excluding 30%) of at least one
RO selected from among BaO, ZnO, and SrO; with the total content of the above-stated
components being equal to or more than 95 percent.