Issued Patents 2004
Showing 1–5 of 5 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 6816449 | Optical pickup compatible with a digital versatile disk and a recordable compact disk using a holographic ring lens | Chul-woo Lee | 2004-11-09 |
| 6791933 | Optical pickup using an optical phase plate | Chul-woo Lee, Chong-sam Chung, Pyong-yong Seong, Kun-ho Cho, Hyun-seob Choi +3 more | 2004-09-14 |
| 6788636 | Optical pickup compatible with a digital versatile disk and a recordable compact disk using a holographic ring lens | Chul-woo Lee | 2004-09-07 |
| 6765857 | Optical recording and pickup head for digital versatile disc compatible with read-writable compact disc by adopting flat plate lens having staircase type diffraction grating structure | Chul-woo Lee, Kun-ho Cho, Pyong-yong Seong | 2004-07-20 |
| 6721243 | METHOD FOR DETECTING SERVO ERROR, APPARATUS THEREFOR, DISK WHICH MAINTAINS QUALITY OF SERVO ERROR SIGNAL, METHOD OF CONTROLLING SERVO OF DISK RECORDING/REPRODUCING APPARATUS, METHOD OF DETECTING TRACKING ERROR, AND METHOD OF DETECTING TILT ERROR | Seong-sin Joo, In-sik Park, Byung-in Ma, Chong-sam Chung, Jung-wan Ko +2 more | 2004-04-13 |