pick up {HEAD ~ means} for sensing {TAIL ~ the object} and generating an image signal of the object including a synchronizing signal; and 
pick up { HEAD ~ means } for sensing { TAIL ~ the object } and generating an image signal of the object including a synchronizing signal ; and
OTH OTH HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH