Claims
- 1. Optical glass for mold pressing having softening capability at a low temperature, consisting in weight percent of:
- ______________________________________ SiO.sub.2 0.5-15% B.sub.2 O.sub.3 0-10% Al.sub.2 O.sub.3 7-20% P.sub.2 O.sub.5 56-80% TiO.sub.2 0-1% ZnO 0-5% MgO 0-10% Li.sub.2 O + Na.sub.2 O + K.sub.2 O 8-25%in which Li.sub.2 O 0-3% Na.sub.2 O 0-5% K.sub.2 O 8-25% Sb.sub.2 O.sub.3 0-1%______________________________________
- wherein the ratio in weight percent of P.sub.2 O.sub.5 to Al.sub.2 O.sub.3 is between 3 and 10; and having a transformation temperature (T.sub.g) of 550.degree. C. or lower.
- 2. Optical glass for mold pressing having softening capability of a low temperature as defined in claim 1 wherein said optical glass has optical constants of a refractive index (Nd) of from 1.50 to 1.60 and an Abbe number (.nu.d) ranging from 62 to 73.
Priority Claims (1)
Number |
Date |
Country |
Kind |
6-131381 |
May 1994 |
JPX |
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CROSS REFERENCE TO RELATED APPLICATION
This application is a continuation-in-part of applicant's application Ser. No. 08/432,083, filed on May 1, 1995, which application is now abandoned.
US Referenced Citations (8)
Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
432083 |
May 1995 |
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