ABSTRACT
Edge filters can be viewed as consisting of a high-reflection band adjacent to an antireflection band. The abruptness of the cut-on or cut-off transition is an important property of edge filters. The usable range of the long-pass filter is from 500 to 900 nm, with a cut-on transition at 650–675 nm. For the short-pass filter, the usable range is from 350 to 600 nm, with the cut-off transition at 460–480 nm. Filters with very abrupt transition edges utilize a very large number of repeating unit cells, on the order of 50. In the case of edge filters, the properties of the passband just outside the stop band are just as important.
