A Closer Look...
The ScanDisk is in action, sweeping the spectrum 1,000 times per second (slowed for obvious reasons!). This animation will be our best effort of demonstrating the movement of light within the DeSa double grating monochromator. In fact, the two monochromators are exact mirror images of each other, so the fan effect of the spectrum in monochromator 1 is exactly duplicated in monochromator 2. The position of the ScanDisk or Spoke Wheel ScanDisk (3) is in the mid-plane (3a) of the monochromator.

          Spoke Wheel ScanDisk