an actuator for moving either the pinhole plate or the focusing lens to control {HEAD ~ the amount} of the first portion of the focused laser beam passing through the pinholes for replaying {TAIL ~ a target track} on the holographic medium, 
for replaying
an actuator for moving either the pinhole plate or the focusing lens to control { HEAD ~ the amount } of the first portion of the focused laser beam passing through the pinholes for replaying { TAIL ~ a target track } on the holographic medium ,
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH