The beam which is reflected by the optical member and the beam which is reflected by the reflecting member after being transmitted through the optical member generate a dual focus on the optical disc, in which {HEAD ~ the dual focus} has {TAIL ~ different focal distances} 
has
The beam which is reflected by the optical member and the beam which is reflected by the reflecting member after being transmitted through the optical member generate a dual focus on the optical disc , in which { HEAD ~ the dual focus } has { TAIL ~ different focal distances }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL