Surface Properties

Surface shapes are defined by using the asphere equation:


R is the radius of curvature. Use negative values to flip orientation.

K is the conic constant.

K Surface Shape
K < -1 Hyperbola
K = -1 Parabola
-1 < K < 0 Ellipse (prolate spheroid)
K = 0 Sphere
K > 0 Ellipse (oblate spheroid)

A2, A4, A6, A8 describe the deviation of the surface from the axially symmetric quadric surface specified by R and K. Note: If K=-1 then A2 is redundant.

To specify a Flat Surface leave all Shape parameters blank.

Specify the component size using the Radius parameter.

Stop parameter allows specifying a lip at the edge of a lens.

Three surface behaviors are allowed:

  • Lens: Rays hitting the surface will be refracted.
  • Mirror: Rays hitting the surface will be reflected.
  • Grating: Rays hitting the surface will be diffracted.