The carbon nanotube film includes {TAIL ~ a number} of {HEAD ~ carbon nanotube strings} substantially parallel to each other and extending along a first direction 
The carbon nanotube film includes { TAIL ~ a number } of { HEAD ~ carbon nanotube strings } substantially parallel to each other and extending along a first direction
OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH