FRED 25.50.1: Optical Engineering Software

FRED 25.50.1 is a June 2026 update from Photon Engineering, with core improvements focused on CAD import capabilities, source management, volume scattering models, and polarization calculations.

Key New Features in Version 25.50.1

New CAD Import (Preview)

FRED ships with a new CAD library that significantly improves import capability:

  • Native Format Support: Direct import of SolidWorks, CATIA, Creo (Pro/E), Autodesk Inventor, and Parasolid native CAD files (FRED Optimum and MPC versions only).

  • Native Surface Conversion: Imported CAD surfaces are preferentially converted to FRED native surface structures, which not only accelerates ray tracing but also enables creation of local reference coordinates. Structures that cannot be converted remain as NURBS surfaces.

  • Complex Geometry Support: Resolves issues where older versions could not recognize complex CAD geometry.

  • Fallback Option: Users can check “Use Legacy CAD Import” to switch back to traditional mode without restarting the software.

Subassembly Functionality Upgrade

Improved management of complex source configurations:

  • Flexible Placement: Subassemblies can now be created within the Optical Sources folder, containing both geometry and optical sources.

  • One-Click Toggle: Multiple sources can be grouped into folders for one-click enable/disable of entire groups.

  • Broken Limitations: Sources can be placed outside the source folder (e.g., in subassemblies within geometry folders), and geometry can be embedded in subassemblies under source folders.

Volume Scattering and Mie Scattering Model Updates

  • FREDmpc Volume Scattering Support: The GPU-accelerated version now officially supports volume scattering.

  • Mean Free Path Calculation: New logic for calculating mean free path based on total particle volume density and average scattering cross-section.

  • Mie Scattering Optimization: Abandons the previous simple particle binning approach in favor of quadratic interpolation using 3 adjacent sample points, resolving non-physical “stair-stepping” in small scattering angle ranges.

  • Power Absorption Algorithm: The Mie volume scattering model now includes power absorption based on the imaginary part of particle refractive index.

Polarization and Material Enhancements

  • New Biaxial Birefringent Media Support.

  • Jones Matrix Algorithm Improvement: Significantly improved algorithm for predicting polarization behavior of Jones Matrix coatings under non-normal incidence. Reflection support is now implemented for the local “Y” polarization component of linear polarizer Jones Matrix types.

  • 3D View Display: Supports intuitive display of material birefringence/GRIN orientation axes for sources, elements, and surfaces in the 3D view.

Other Practical Updates

  • Zernike Surfaces: Added X and Y axis offset parameters for Zernike polynomials, plus offset and tilt settings for Zernike conical base surfaces, equivalent to definitions in CodeV and Zemax.

  • New Script Command: CopyEntity command for duplicating objects within the software tree structure.

  • Preference Saving: Two new options in the “Tools” menu allow users to manually save FRED preferences to a file or registry, and load settings from a file or registry.

  • New Curve Type: Cubic Hermite polynomial 3D curve type added.

fred 2026