In one embodiment {TAIL ~ a dispersive element} is used to reflect the input beam at {HEAD ~ different angles} depending on the incident wavelength 
In one embodiment { TAIL ~ a dispersive element } is used to reflect the input beam at { HEAD ~ different angles } depending on the incident wavelength
OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH