A source with adjustable coherence length is devised and used to illuminate
an OCT for en-face imaging of the retina of the human eye in vivo. Two mod
es of operation are described. The added capability of adjusting the depth
resolution in real time while imaging patients is discussed. The utility of
the OCT err-face imaging with adjustable coherence length for diagnostic i
s illustrated by images taken from the eye of a volunteer. Similar images w
ith those produced by scanning laser ophthalmoscopes are produced for the f
irst time in real time using OCT.