Technical Issues - Diabatic Transmittance Scale
The Schott diabatic transmittance scale [1-log(log(1/t))] conveniently displays passbands and blocking regions on the same graph. This scale is now available in the DESIGN 2.61.1040 and MEASURE 2.51.0220 FSPlot Module. There is a choice of (0-1) or (0-100%) ranges.
Assuming that the vertical axis is transmittance, click Transmittance Format in the FSPlot Setup menu to select linear or diabatic formats. Annotations are added in the usual way, and automatic annotations as shown below are supported. Annotations developed for the 0-100% linear scale will work on the 0-100% diabatic scale.
Although FSPlot can also display %T and optical density on the same graph, the diabatic scale has the clear advantage when displaying bandwidth in the blocking zone. It should be mentioned that the usual definition of diabatic is different from Schott's (and FilmStar's) definition.
Users anxious to try this example will find
FnumDiabatic.faw and BandWidthPlotII.bas in
usual, copy *.faw to c:\Winfilm\Designs and *.bas to c:\Winfilm\Basic32.