Patent ID: 8735308
Filing Date: 2014-05-27
Classification: C03B,C03C

Abstract:
1. An optical member comprising a TiO 2 -containing silica glass having: a TiO 2 concentration of from 3 to 10% by mass; a Ti 3+ concentration of 100 wt ppm or less and greater than 0 ppm; a thermal expansion coefficient at from 0 to 100° C., CTE 0-100 , of 0±150 ppb/° C.; and an internal transmittance in the wavelength region of 400 to 700 nm per a thickness of 1 mm, T 400-700 , of 80% or more, wherein the optical member has a ratio of variation of Ti 3+ concentration to an average value of the Ti 3+ concentration, ΔTi 3+ /Ti 3+ , on an optical use surface, of 0.2 or less.