Optical and Photonic Solutions Blog


Lens Surface Conversion Increases Flexibility for Refining Surface Geometry in LightTools

One of the many new features introduced in LightTools 2023.03 is the powerful capability to convert a lens surface from one type to another while retaining the same shape. The conversion works with native optical surface shapes in LightTools, as well as with geometry imported from other CAD software. This means you can import geometry and convert the shape to a native lens shape such as freeform, Zernike, Q-type surface, for example. After the conversion, you can then adjust the shape as you would any other native surface shape in LightTools. This conversion makes it possible to use the surface shape to improve a system design as part of an optimization and more easily perform a tolerance analysis by adjusting the converted surface.

Converting a lens surface is easy: just select the surface you want to fit and choose Convert to Lens Surfaces on the Modify > Lens menu, shown below.

LightTools makes a copy of the surface, fit to a LightTools Freeform shape.

Freeform is the default type for the conversion, but you can change it to another native shape available in LightTools simply by clicking the Type option and selecting another type from the list. LightTools performs the fit automatically, finding the coefficients to retain the original surface shape as closely as the new type allows.

Because the geometric part becomes a native parametric entity, you can adjust it like any other entity made in LightTools. (Tip: Change the Type to a Super Freeform to add Compounding Geometry to assess surface deformations from the base shape!)

For a more detailed look at this feature, LightTools customers are invited to watch this 10-minute Quick Tip: LightTools Surface Conversion in the Synopsys Learning Center (SolvNetPlus account is required).

While we focused on the surface conversion here, this is one of many geometry enhancements provided in LightTools 2023.03. Other enhancements include:

  • Evolved conic surfaces
  • Freeform surfaces defined by non-uniform rational basis splines (NURBS)
  • More realistic control of lens apertures and holes

LightTools 2023.03 also includes a versatile Section View feature, simulation enhancements for coherent and polarization systems, and more. For details, see our previous blog post or datasheet.