Claims
- 1. A light filter which is made by forming a dielectric film on glass-ceramics, said glass-ceramics having a coefficient of expansion within a range from 95×10−7/°C. to 140×10−7/°C. within a temperature range from −20° C. to +70° C.
- 2. A light filter which is made by forming a dielectric film on glass-ceramics having a larger coefficient of thermal expansion than dielectric which constitutes the dielectric film, said glass-ceramics having a coefficient of expansion within a range from 95×10−7/°C. to 140×10−7/°C. within a temperature range from −20° C. to +70° C. and having a Young's modulus of 85 GPa or over.
Priority Claims (1)
Number |
Date |
Country |
Kind |
11-226947 |
Aug 1999 |
JP |
|
Parent Case Info
This is a divisional of application Ser. No. 09/551,043 filed Apr. 17, 2000, now U.S. Pat. No. 6,410,466. Priority of application Ser. No. 226947/1999 filed on Aug. 10, 1999 in Japan is claimed under U.S.C. §119.
US Referenced Citations (3)