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Pentprsm shows the use of special aperture data, as well as 3d boundary (bdi) data, used to enter data for a pentaprism. A pentaprism changes the direction of a beam by 90 degrees. It is straightforward to enter such a system using the bend command in OSLO. However, to draw a picture of the system requires special work because of the nature of the prism. The system shown here uses OSLO's boundary information ( bdi) to draw the prism, as shown in the figure below.


The pentaprism system included here is intended as a base system into which you can insert your own optics as required. Blank pieces of glass are placed in front and behind the prism for demonstration. The data are shown in the following list.

From an optical standpoint, the interesting surfaces are 3-6. The orientation of the surfaces is straightforward and easily handled by the ben command. The sides of the prism are rectangular, so each surface must have a rectangular special aperture, calculated according to the standard pentaprism geometry. Since the actual prism surfaces are to be represented by bdi information (in contrast to being enclosed in a bounding box, cf. anaprism.len ), it is important that the drawing information accurately represent the true situation.