| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a crystallized glass of which the average linear expansion coefficient at from 0 to 50°C is very small and the variation of inclination of a ΔL/L curve is very small; more specifically, to provide a crystallized glass of which the average linear expansion coefficient at from 0 to 50°C is 0.0±0.2×10<SP>-7</SP>/(°C), the absolute value of the difference between the maximum value and minimum value of ΔL/L at from 0 to 50°C is 10×10<SP>-7</SP>or less, and the value of a dCTE/dT-temperature curve at from 20 to 30°C is in a range between -1.5 to +1.5 ppb/(°C)<SP>2</SP>. <P>SOLUTION: The crystallized glass includes a β-quartz and/or β-quartz solid solution, and the variation of the refractive index nd appearing before and after crystallization is 0.04 or less. <P>COPYRIGHT: (C)2011,JPO&INPIT |
