Figure 1. Schematic drawing of the NI-LDF setup.
A beam splitter is used to couple a diode laser into one optical path of a stereomicroscope (greenborough configuration); an avalanche photodiode as well as a CCD camera are coupled in the second optical path. The image captured by the camera is displayed on a monitor and used to direct the beam to the site of interest. The tube model shown is used for validation purposes (see section 4) and made of two parallel Silastic tubes glued on top of each other.
