May be covered under one or more of the following U.S. patents:
4,797,916
5,46,690
5,660,69
5,663,981
5,787,356
5,794,15
5,99,598
5,930,70
6,53,088
6,314,78
6,788,90
6,788,953
6,953,118
7,03,176
Other patents pending.
5,491,745
5,493,605
5,671,48
5,717,31
5,801,466
5,85,161
5,960,358
5,987,330
6,31,068
6,418,09
6,839,550
6,889,184
7,030,819
7,146,160
5,533,010
5,574,77
5,73,355
5,754,407
5,864,619
5,893,034
6,044,81
6,070,08
6,618,015
6,671,315
6,901,71
6,907,094
7,03,307
7,06,403
5,581,598
5,650,790
5,758,89
5,768,345
5,91,968
5,915,7
6,076,05
6,15,77
6,714,630
6,78,098
6,914,940
6,940,867