{HEAD ~ The screen} is scanned by a laser spot having a diameter which is {TAIL ~ less than 100 micrometer} 
{ HEAD ~ The screen } is scanned by a laser spot having a diameter which is { TAIL ~ less than 100 micrometer }
HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL