US Patent # | Date Issued | |
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2. | 5,484,285 | January 16, 1996 |
3. | 5,499,918 | March 19, 1996 |
4. | 5,749,731 | May 12, 1998 |
5. | 5,827,062 | October 27, 1998 |
6. | 5,888,066 | March 30, 1999 |
7. | 6,200,345 | March 13, 2001 |
8. | 6,227,857 | May 8, 2001 |
9. | 6,290,500 | September 18, 2001 |
10. | 6,325,628 | December 4, 2001 |
11. | 6,592,370 | July 15, 2003 |
12. | 6,688,887 | February 10, 2004 |
13. | 6,991,462 | January 31, 2006 |