Claims
- 1. A method of manufacturing a glass optical element with high precision by press molding a glass substance, comprising the steps of:preparing a mold that has a molding surface which comprises silicon and which is polished into a mirror surface, preparing a dehydrated glass substance as the glass substance, heating and softening the dehydrated glass substance, and press molding the dehydrated glass substance with the molding surface to form the glass optical element.
- 2. The method of claim 1 the molding surface is covered with a releasing film.
- 3. The method of claim 2 wherein the molding surface comprises silicon carbide or silicon nitride.
- 4. The method of claim 3 wherein the dehydrated glass substance comprises substantially no arsenic oxide.
- 5. The method of claim 4 wherein the dehydrated glass substance comprises an amount of an antimony oxide.
- 6. The method of claim 3 wherein preparing the glass substance comprises forming glass perform by dripping a glass melt over a reception plate and by shaping the glass melt over a gas spouted from the reception plate.
- 7. The method of claim 3 wherein the dehydrated glass substance contains a total content of hydroxyl groups and water molecules not greater than 50 ppm in terms of water molecules.
- 8. The method of claim 7 wherein the press molding is carried out within a non-oxidizing atmosphere.
- 9. The method of 7 wherein the dehydrated glass substance has a total content of hydroxyl groups and water molecules not greater than 25 ppm in terms of water molecule.
- 10. The method of claim 3 wherein the releasing film comprises a layer comprising carbon.
- 11. The method of 3 wherein the dehydrated glass substance has a sag point of not higher than 565° C.
- 12. A method of manufacturing a glass optical element with high precision by press molding a glass substance, comprising the steps of:preparing a mold that has a molding surface which comprises silicon and which is polished into a mirror surface, preparing the glass substance having a total content of hydroxyl groups and water molecules not greater than 50 ppm in terms of water molecules, heating and softening the glass substance, and press molding the glass substance with the molding surface to form the glass optical element.
- 13. The method of claim 12 wherein the molding surface is covered with a layer comprising carbon.
- 14. A method of manufacturing a glass optical element with high precision by press molding a glass substance, using a mold with surface defects reduced on a molding surface, comprising the steps of:preparing a mold wherein the molding surface comprising silicon, preparing a dehydrated glass substance; heating and softening the dehydrated glass substance, and press molding the dehydrated glass substance in the mold to form the glass optical element.
- 15. The method of claim 14 wherein the molding surface is covered with a releasing film.
- 16. The method of claim 15 wherein the molding surface comprises silicon carbide or silicon nitride.
- 17. The method of claim 16 wherein the releasing film comprises a layer comprising carbon.
Priority Claims (1)
Number |
Date |
Country |
Kind |
7-238671 |
Sep 1995 |
JP |
|
Parent Case Info
This is a divisional of application No. 09/150,894, filed Sep. 10, 1998, now U.S. Pat. No. 6,151,915 which is a Divisional of Application No. 08/715,415 filed Sep. 18, 1996, now U.S. Pat. No. 5,919,718 the disclosure of which is incorporated herein by reference.
US Referenced Citations (14)
Number |
Name |
Date |
Kind |
3961927 |
Alderson et al. |
Jun 1976 |
A |
4438211 |
Mennemann et al. |
Mar 1984 |
A |
4460696 |
Harada et al. |
Jul 1984 |
A |
4521524 |
Yamashita |
Jun 1985 |
A |
4600425 |
Krumwiede et al. |
Jul 1986 |
A |
4686196 |
Gliemeroth et al. |
Aug 1987 |
A |
4812423 |
Kodama et al. |
Mar 1989 |
A |
5039631 |
Krashkevich et al. |
Aug 1991 |
A |
5125949 |
Hirota et al. |
Jun 1992 |
A |
5364433 |
Nishimura et al. |
Nov 1994 |
A |
5472918 |
Onozawa |
Dec 1995 |
A |
5676723 |
Taniguchi et al. |
Oct 1997 |
A |
5679125 |
Hiraiwa et al. |
Oct 1997 |
A |
5744409 |
Hashimoto et al. |
Apr 1998 |
A |
Foreign Referenced Citations (7)
Number |
Date |
Country |
63-45134 |
Feb 1988 |
JP |
2-120245 |
May 1990 |
JP |
2-199036 |
Aug 1990 |
JP |
4-61816 |
Oct 1992 |
JP |
5-201743 |
Aug 1993 |
JP |
6-345461 |
Dec 1994 |
JP |
8-104528 |
Apr 1996 |
JP |