| 摘要 |
<p>A quartz glass member used together with light having a specified wavelength of up to 250 nm, characterized in that the difference between maximum and minimum values of hydroxyl group concentrations at a plurality of measuring points within a plane having its center at the intersection between the light and the optical axis of the quartz glass member and being perpendicular to the optical axis is up to 50 ppm, double refraction values at a plurality of locations within the same plane as above one are measured, and a plurality of signed double refraction values obtained based on the plurality of double refraction values and their phase advance axis directions are -2.0 to +2.0 nm/cm, whereby providing a quartz glass member high in light transmitting and ultraviolet ray resisting features.</p> |
