An alkali-free glass having a strain point of 650 C. or more, an average coefficient of thermal expansion at 50 to 350 C. of from 3010.sup.7 to 4510.sup.7/ C., and a temperature T.sub.2 at which a glass viscosity reaches 10.sup.2 dPa.Math.s of from 1,500 to 1,800 C. The alkali-free glass contains, as represented by mol % based on oxides, SiO.sub.2: from 62 to 70%, Al.sub.2O.sub.3: from 9 to 16% B.sub.2O.sub.3: from 0 to 12%, MgO: from 3 to 10%, CaO: from 4 to 12%, SrO: from 0 to 6%, and Fe.sub.2O.sub.3: from 0.001 to 0.04%, provided that MgO+CaO+SrO+BaO is from 12 to 25%. The alkali-free glass has a -OH value of from 0.35 to 0.85/mm.

Manufacturing is facilitated while deflection is suppressed, and transmission ability is increased. A glass (10) contains SiO.sub.2: 40% to 60%, B.sub.2O.sub.3: 0.01% to 15%, and Al.sub.2O.sub.3+rare earth oxide: 0% to 20% as expressed in mol % on an oxide basis, and the ratio of the total content of Al.sub.2O.sub.3 and RO to the total content of SiO.sub.2, Al.sub.2O.sub.3, and RO (that is, (Al.sub.2O.sub.3+RO)/(SiO.sub.2+Al.sub.2O.sub.3+RO)) is 0.38 or more.

Manufacturing can be facilitated while deflection is suppressed. A glass (10) has a Young's modulus of 95 GPa or more, a coefficient of linear thermal expansion of 5.5 ppm/ C. or less, and a devitrification suppression parameter value represented by Formula (1) of 6.0 or more.

An alkali-free glass having a strain point of 650 C. or more, an average coefficient of thermal expansion at 50 to 350 C. of from 3010.sup.7 to 4510.sup.7/ C., and a temperature T.sub.2 at which a glass viscosity reaches 10.sup.2 dPa.Math.s of from 1,500 to 1,800 C. The alkali-free glass contains, as represented by mol % based on oxides, SiO.sub.2: from 62 to 70%, Al.sub.2O.sub.3: from 9 to 16% B.sub.2O.sub.3: from 0 to 12%, MgO: from 3 to 10%, CaO: from 4 to 12%, SrO: from 0 to 6%, and Fe.sub.2O.sub.3: from 0.001 to 0.04%, provided that MgO+CaO+SrO+BaO is from 12 to 25%. The alkali-free glass has a -OH value of from 0.35 to 0.85/mm.