Glass compositions with high Young's modulus are disclosed. The glass compositions may include phosphorus oxide (P.sub.2O.sub.5), alumina (Al.sub.2O.sub.3), boron oxide (B.sub.2O.sub.3), lithium oxide (Li.sub.2O), magnesia (MgO), titania (TiO.sub.2), lanthanum oxide (La.sub.2O.sub.3) and other components.

Glass compositions with high Young's modulus are disclosed. The glass compositions may include phosphorus oxide (P.sub.2O.sub.5), alumina (Al.sub.2O.sub.3), boron oxide (B.sub.2O.sub.3), lithium oxide (Li.sub.2O), magnesia (MgO), titania (TiO.sub.2), lanthanum oxide (La.sub.2O.sub.3) and other components.

A fiber optic plate 122 including a plurality of core glasses 122a, a clad glass 122b covering the core glass 122a, and a light-absorbing glass 122c disposed between the plurality of core glasses 122a, wherein a content of TiO.sub.2 in the core glass 122a is 7% by mass or less, a content of B.sub.2O.sub.3 in the core glass 122a is 15% by mass or more, and a content of WO.sub.3 in the core glass 122a is more than 0% by mass.

A fiber optic plate 122 including a plurality of core glasses 122a, a clad glass 122b covering the core glass 122a, and a light-absorbing glass 122c disposed between the plurality of core glasses 122a, wherein a content of TiO.sub.2 in the core glass 122a is 7% by mass or less, a content of B.sub.2O.sub.3 in the core glass 122a is 15% by mass or more, and a content of WO.sub.3 in the core glass 122a is more than 0% by mass.

Glass compositions include boron oxide (B.sub.2O.sub.3), lanthanum oxide (La.sub.2O.sub.3), tungsten oxide (WO.sub.3) and zirconia (ZrO.sub.2) as components and may optionally include niobia (Nb.sub.2O.sub.5), titania (TiO.sub.2), bismuth oxide (Bi.sub.2O.sub.3), yttria (Y.sub.2O.sub.3), tellurium oxide (TeO.sub.2), SiO.sub.2, PbO and other components. The glasses may be characterized by high refractive index at 587.56 nm and low density at room temperature relative to known glasses.

Glass compositions include boron oxide (B.sub.2O.sub.3), lanthanum oxide (La.sub.2O.sub.3), tungsten oxide (WO.sub.3) and zirconia (ZrO.sub.2) as components and may optionally include niobia (Nb.sub.2O.sub.5), titania (TiO.sub.2), bismuth oxide (Bi.sub.2O.sub.3), yttria (Y.sub.2O.sub.3), tellurium oxide (TeO.sub.2), SiO.sub.2, PbO and other components. The glasses may be characterized by high refractive index at 587.56 nm and low density at room temperature relative to known glasses.

Glass compositions include titania (TiO.sub.2), lanthanum oxide (La.sub.2O.sub.3), boron oxide (B.sub.2O.sub.3), silica (SiO.sub.2) as essential components and may optionally include zirconia (ZrO.sub.2), niobia (Nb.sub.2O.sub.5), calcium oxide (CaO), barium oxide (BaO), yttria (Y.sub.2O.sub.3), zinc oxide (ZnO), gadolinium oxide (Gd.sub.2O.sub.3), gallia (Ga.sub.2O.sub.3), tungsten oxide (WO.sub.3) and other components. The glasses may be characterized by high refractive index at 587.56 nm at comparably low density at room temperature.

Glass compositions include titania (TiO.sub.2), lanthanum oxide (La.sub.2O.sub.3), boron oxide (B.sub.2O.sub.3), silica (SiO.sub.2) as essential components and may optionally include zirconia (ZrO.sub.2), niobia (Nb.sub.2O.sub.5), calcium oxide (CaO), barium oxide (BaO), yttria (Y.sub.2O.sub.3), zinc oxide (ZnO), gadolinium oxide (Gd.sub.2O.sub.3), gallia (Ga.sub.2O.sub.3), tungsten oxide (WO.sub.3) and other components. The glasses may be characterized by high refractive index at 587.56 nm at comparably low density at room temperature.

An optical glass includes La.sup.3+, Zn.sup.2+, Nb.sup.5+, and Ti.sup.4+ as a cation configuring glass. La.sup.3+, Zn.sup.2+, Nb.sup.5+, and Ti.sup.4+ which satisfy 10 cat %≤La.sup.3+≤20 cat %, 10 cat %≤Zn.sup.2+≤60 cat %, 20 cat %≤Nb.sup.5+≤60 cat %, and 0 cat %≤Ti.sup.4+≤40 cat % expressed by cation %.

Glass compositions include boron oxide (B.sub.2O.sub.3), lanthanum oxide (La.sub.2O.sub.3), titania (TiO.sub.2) and niobia (Nb.sub.2O.sub.5) as essential components and may optionally include silica (SiO.sub.2), tungsten oxide (WO.sub.3), zirconia (ZrO.sub.2), yttria (Y.sub.2O.sub.3), bismuth oxide (Bi.sub.2O.sub.3), barium oxide (BaO), TeO.sub.2 and other components. The glasses may be characterized by high refractive index at 587.56 nm at comparably low liquidus temperature.