The reflectance illumination is directed toward the objective and sample by a fully reflective mirror, which injects {HEAD ~ approximately half} of the interferometer beam into the microscope, and permits substantially all of the reflected beam to reach {TAIL ~ the detector} 
The reflectance illumination is directed toward the objective and sample by a fully reflective mirror , which injects { HEAD ~ approximately half } of the interferometer beam into the microscope , and permits substantially all of the reflected beam to reach { TAIL ~ the detector }
OTH OTH OTH OTH 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 OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL