Systems of the camera 31 and {TAIL ~ the USB host} 35 are identical to those of the related art, but {HEAD ~ the interface unit} 33 has a system as follows 
Systems of the camera 31 and { TAIL ~ the USB host } 35 are identical to those of the related art , but { HEAD ~ the interface unit } 33 has a system as follows
OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH