About
The links and obturations table allows first to define links between two consecutive surfaces of the system and second to enter obturation parameters according to the aperture type defined in the mandatory parameters table.
Links
Except for the object surface, the link cell enables to link a surface to the precedent one in system and ray tracing illustrations. This allows to provide a realistic display of an optical component (a lens for for instance). If the link cell of a given surface is activated (the selection is then the identifier of the precedent surface), the surface shall be joined to the precedent one in the "2D system", "2D ray tracing", "3D system", "3D wireframe ray tracing" and "3D texture ray tracing".
Note that if "automatic" is selected in the links cell of the options table, links are automatically managed without considering the entered parameters in the link cell of the links and obturation table.
Obturations
Apart of the link cell, other cells of the links and obturations table are activated if an aperture is requested in the aperture selection list of the mandatory parameters table for a given surface.
---Dmax---
It is activated if circular aperture or circular obturation is selected in the mandatory parameters table. Dmax becomes then the "new" clear aperture diameter of the surface.
---Dmin---
It is activated if circular obturation is selected in the mandatory parameters table. All rays inside a circle of diameter Dmin are blocked so that the aperture has an annular shape.
---Xmax and Ymax---
These cells are activated if rectangular aperture or rectangular obturation is selected in the mandatory parameters table. They define the boundaries dimensions of the rectangular clear aperture respectively along the X and Y axis.
---Xmin an Ymin ---
These cells are activated if rectangular obturation is selected in the mandatory parameters table.
They define a rectangle blocking rays and which dimensions along the X and Y axis are respectively Xmin an Ymin.
Note that if an aperture is requested in the mandatory parameters table, parameters Dmax or Xmax and Ymax defined in the links and obturations define the physical boundaries of the surface for their display.
For more details concerning the links and obturations table, see the related tutorial.