28220026HUNANCOMMUNICATIONSCIENCEANDTECHNOLOGYVol.28No.2Jun.2002:10082844X(2002)0220093202X(,410001):,,,,:;;:U412136+611:B,,199810,19991031,2a,,1,,,,,,(),,,,,,,,,,,(),:,,,,3(),,,,,,,,,,,,,,,,,,,,,,,,199812,:90%,,?2017,,1a1200,,1a6000,500,,4200,,X:2002204218©1995-2005TsinghuaTongfangOpticalDiscCo.,Ltd.Allrightsreserved.,1a030t,1L1,315,?,,,:,,,,,;,;,,,,?,,,,,??3,,,,,,,,,,,,,,,,,,,,,,4,,,,,,,,,200111,(),,2000,,,,,,:,;;;,;,,,,,:,,,,,,,:[1].:,1997.4928©1995-2005TsinghuaTongfangOpticalDiscCo.,Ltd.Allrightsreserved.