Optical Design Exchange Overview

Context

In the design of imaging systems, analyzing stray light and assessing image quality require to consider the lens geometries and the opto-mechanical elements that constrain them.

Ghost analysis is typically performed in Ansys Zemax OpticStudio during the design of the free-floating lenses. Then, the optical design created with Ansys Zemax OpticStudio can be imported into Speosto perform stray light analysis using the Speos capabilities:

Using the CAD in which Speos is integrated you can add the opto-mechanical elements or modify the lenses to apply mechanical constraints.
You can perform the stray light analysis while considering the opto-mechanical elements.


Stage 1	Stage 2	Stage 3

Optical design and optimization Ghost analysis in Ansys Zemax OpticStudio	Optical design import to Speos (geometries, optical properties and sensors)	Optomechanical design Stray light analysis of the complete system in a virtual scene

In Speos

Speos provides you with the Optical Design Exchange feature which allows you to import a complete optical lens design created in Ansys Zemax OpticStudio.

Upon compute, the Optical Design Exchange feature imports the following elements to Speos:

Geometries created in the SpaceClaim Structure tree
Optical properties created as Material features in the Speos Simulation tree
Imager(s) created as Irradiance sensor(s) in the Speos Simulation tree
Meshing created as Local Meshing in the Speos Simulation tree
Sources created as Surface sources in the Speos Simulation tree

These imported elements created in the Speos Simulation tree and the SpaceClaim Structure tree represent what has been exported from Ansys Zemax OpticStudio.

Migration information from version 2025 R2

As of version 2025 R2, the Optical Design Exchange workflow has been standardized to correspond to classical Speos workflow.

Before 2025 R2: Optical Properties information (material, coating) were integrated directly into the Optical Design Exchange feature (Speos feature). As a consequence, you had to include the Optical Design Exchange feature in a simulation or a Speos Light Box export for the Optical Properties and the Geometries to be considered.
As of 2025 R2: Imported Optical Properties from an *.odx file are created in Material features (Speos feature). Material features reference the lens geometries linked to them. As a consequence, to define a Speos feature (3D sensors, simulations, etc.) relying on geometries, you can now select the geometries from the SpaceClaim Structure tree. The associated Materials will be shipped with the geometries.

Note: You can still directly select and add the Optical Design Exchange feature to the simulation. The list of the geometries will implicitly inherit from all the geometries of the feature.

Characteristics

The Optical Design Exchange (ODX) feature can be included:
- in a Light Box Export
  The Light Box can be black-boxed.
- directly in a simulation as geometry.

Important:

You cannot add an ODX feature as input of a LiDAR simulation.
If you still want to use the geometries of the ODX feature, you need add the geometries in the LiDAR simulation from the Structure panel.
To avoid propagation error, do not select an ODX component and its generated geometries in the same simulation or Speos Light Box Export.

Limitations

Speos applies an Optical Polished surface optical property when no surface optical property (coating) is specified on a face in Ansys Zemax OpticStudio. This may lead to unwanted Speos simulation results. Make sure optical properties are applied in Ansys Zemax OpticStudio to avoid such issues.
Speos may generate unexpected simulation results if integrated rays are outside of the wavelength range defined. Therefore, when defining sources and sensors in a simulation containing the imported optical design system, make sure to consider the spectral range of the Optical Design Exchange feature.

This warning can be activated/deactivated.
ODX features are not compatible with the Fast Transmission Gathering algorithm (FTG). If you apply Fast Transmission Gathering in a simulation, the ODX feature will ignore it.
In some systems, the aperture Stop (in sequential mode) corresponds to the surface of a lens. In this case the surface of the Stop is positioned at the origin of the lens' surface. A problem arises when the lens is curved as the offset from the origin due to the curve is not taken into account. A workaround would be
- to create a dummy surface that fits precisely with the edge of the lens
- to add a STOP to that dummy surface, with the same aperture as the surface
- and to place that STOP at the location of the edge of the surface.
CAUTION: Workaround will not work on everycase. For instance, non-rotational symmetric surface, for which the position of the edge is different around the diameter.
After computing an Optical Design Exchange feature containing a *.odx file with several Irradiance sensors:
1. if you delete one of the Irradiance sensors,
2. then recompute the Optical Design Exchange feature,
3. the deleted Irradiance sensor appears again (correct behavior) but with a wrong name (incorrect behavior).

Generic Workflow

Design Creation Stage

You create the optical design system using Ansys Zemax OpticStudio.
When creating the system, you must apply surface properties to Annulus surface. We recommend you to use the "ABSORB" material. Otherwise Speos will not be able to read the surface correctly.
The STOP surface has no optical property and is considered as absorbent.
You export the optical design system in a readable file for Speos (*.odx).
The *.odx file includes the geometries of the system with their position and orientation, the position and orientation of the imager, the materials and coatings, and sources used in the system.

Important: Only *.odx files exported from OpticStudio sequential systems (SEQ) can include source information.

Import and Checking Stage

In Speos, you import and position the optical design system contained in the *.odx file using the Optical Design Exchange feature.
Ansys Zemax OpticStudio is not needed to import the *.odx file.
You compute the Optical Design Exchange feature.
A list of elements are created in the Speos Simulation tree and in the SpaceClaim Structure tree.
You must verify that:
- each SpaceClaim geometry (Structure tree) is correctly associated to their Speos Objects, Surfaces, Solid Bodies (Speos Simulation tree).
- Material features created out of the imported optical properties are associated to their correct geometries.
- the Local Meshing created out of the imported *.odx file references all the geometries.

Design Use and Analysis Stage

Once the Optical Design Exchange feature is created and all the elements imported:

According to the goal of the project:
1. You start designing the opto-mechanical parts, or, import opto-mechanical parts designed in other CAD platforms.
  -and/or-
2. You modify the geometries of the system to apply mechanical constraints.
3. If needed, you can add Face Optical Properties (FOP) to the geometries.
  In this case, the default surface properties on the selected faces of the ODX feature geometries will be overridden by the FOP that has been defined on them.
You modify the Local Meshing of the Optical Design Exchange geometries.
You create a Simulation (Interactive, Direct, Inverse):
1. Add the Surface sources imported from *.odx file and other sources if necessary.
2. Add the Irradiance Sensors imported from *.odx file and other sensors if necessary.
3. Add the geometries (Structure tree) imported from *.odx file to the Geometries list and other geometries if necessary.
Once the simulation is defined, you run the simulation.
You analyze the result using the Speos tools and workflow (Light Expert, Stray Light Analysis, Virtual Photometric Lab, Virtual Human Vision Lab).