Issued Patents All Time
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5830605 | Gradation mask method of producing the same and method of forming special surface profile on material using gradation mask | Kazuhiro Umeki, Masaaki Sato | 1998-11-03 |
| 5776639 | Exposure mask, method of producing the same, exposure mask producing apparatus, and method of forming surface profile on material using exposure mask | Kazuhiro Umeki | 1998-07-07 |