| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a synthetic silica glass having excellent white devitrification resistance and black devitrification resistance and also having high heat resistance, to provide a method for producing the same, and to provide a device provided with a member generated by the synthetic silica glass. <P>SOLUTION: There is a synthetic silica glass in which OH group concentration is≤5 ppm, the total of meal impurity concentrations is≤1 ppm, the amount of oxygen-depleted type defects at 250 nm is 0.01 to 6/cm by an absorption coefficient, an absorption coefficient at 215 mm is lower than an absorption coefficient at 250 nm, and also, viscosity at 1,100°C is 10<SP>14</SP>to 10<SP>16</SP>poise. Particularly, in the synthetic silica glass, the internal transmittance of light with a wavelength of≤250 nm is controlled to≤50 %/cm for an arc tube for a lamp. Also there are a method for producing the same and a device provided with a member generated by the synthetic silica glass. <P>COPYRIGHT: (C)2010,JPO&INPIT</p> |
