Issued Patents 1997
Showing 1–4 of 4 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5682239 | Apparatus for detecting positional deviation of diffraction gratings on a substrate by utilizing optical heterodyne interference of light beams incident on the gratings from first and second light emitters | Takahiro Matsumoto, Koichi Sentoku | 1997-10-28 |
| 5670809 | Non-volatile semiconductor memory device | — | 1997-09-23 |
| 5625453 | System and method for detecting the relative positional deviation between diffraction gratings and for measuring the width of a line constituting a diffraction grating | Takahiro Matsumoto, Yoshiaki Ohtsu, Koichi Sentoku | 1997-04-29 |
| 5610718 | Apparatus and method for detecting a relative displacement between first and second diffraction gratings arranged close to each other wherein said gratings have different pitch sizes | Koichi Sentoku, Takahiro Matsumoto, Noriyuki Nose, Minoru Yoshii | 1997-03-11 |