How it works: This unique optical design of the DG-4, is based on dual scanning
galvanometers. Thewavelength selection is done by interference filters. The DG-4 can host up to four 25mminterference filters. The light coming from the 175W xenon arc lamp is focused on the
firstgalvanometer mirror. The light is then directed, via a parabolic mirror, through one of theoptical channels that may contain an interference filter. The light passing through the filter
iscollected by another parabolic mirror and sent to a second scanning mirror that directs it to aliquid light guide. The light guide can be coupled to the illumination port of an instrument(e.g. epi
illumination port of a microscope). The intensity of the output can be modulated bycontrolling the relative orientation of the two scanning mirrors. Thus this system can providenarrow band excitation
at selected wavelengths over a range of intensities or can rapidlyurn off the light source. Dwell time at any wavelength is arbitrarily set by the user.Transitions are achieved in less than 1.2msec.