New tool will streamline the FEA process in optics development.
Recently, Zemax announced that the newest release of its OpticStudio software would include new modules for structural, thermal, and optical properties. The Structural, Thermal, Analysis and Results (STAR) is the new module from the 21.2 release that will simplify communication between finite element analysis (FEA) programs and OpticStudio. Zemax is a company that’s been working in the optics field since the time that the first Hubble telescope was launched in 1990. The vision for the company still follows its founder’s words—“to offer a rock-solid physics architecture, to uphold a culture of excellence and innovation, and to always listen to our customers.”
The Photonics Industry
When the International Society for Optics and Photonics (SPIE) published its Fall 2020 Industry Report, the field of photonics looked bright and booming. Photonics component production employed more than 1 million people worldwide, spanning more than 50 countries. Global revenue from components accounted for $282 billion in 2018, and the industry has shown growth above global GDP since 2012. As an optics software producer, Zemax recognizes that optics companies are under pressure to bring more and more components to market faster. The white paper “Designing for Manufacturability: Bring optical systems to market more quickly and cost-effectively through a streamlined engineering workflow” discusses some of the roadblocks to production that Zemax has noticed in the industry and suggests some possible solutions.
Zemax and Designing for Manufacturability
One of the biggest issues slowing the development of optical components is the separation of engineering teams. Optical engineers, design engineers and manufacturing engineers are all working on the same product or service concurrently and using different tools in the development process.
Optical engineers are under pressure to keep the number of defects low, but their tools aren’t always optimized for yield. Finding the right mix of inputs to create components that can be manufactured at high volumes with high yield and low defect rates can be difficult. Design engineers often need to recreate the part models that the optical engineers are building, and each iteration requires new or updated models. Manufacturing engineers receive file formats that are “overly restrictive,” and as the design evolves their equipment needs to be adjusted and reconfigured. These are problems that can occur in any industry, but the specialized nature of optical software can place even more burden on the system and require much more interaction between the three groups.
Zemax works to help address these issues with software that works across the silos, with OpticStudio for optical engineers, OpticsBuilder for design engineers, and OpticsViewer for manufacturing engineers. Each software product talks back and forth to the others with common file formats and lets each sector review designs as they change. The common language lets optical engineers upstream instantly see the effect that their changes have on the design and manufacturing engineers. This should save all the parties involved time and eventually money in the development and manufacturing processes, while limiting defects on the production side.
The New STAR of the Optical Software Sky
Beyond the streamlining of different engineering disciplines, the STAR module is built to bring in FEA information from any source. Performing structure, thermal and optical performance (STOP) analysis will bring FEA engineers into the mix right along with optical engineers, design engineers and manufacturing engineers. Bringing these functions into OpticStudio will allow “optical engineers of all experience levels to easily visualize and analyze the impact of structural and thermal factors within one solution.”
Zemax hopes that these new sets of visual and data fitting tools will help the teams to eliminate even more time and duplication of effort from the development process. The FEA data should show how the components will exist in their use environment while giving additional insight into any stresses or concerns that might occur in the entire manufacturing process.
Getting into the technical specifications of the software, the STAR API integrates itself right into OpticStudio’s ZOS-API. Any FEA package can be used provided the data format is a tab delimited text file with decimal formatted numbers. Zemax notes that the decimal comma format is not supported for the STAR system, just as it is not supported for the company’s other software. For structural deformation models, six columns are used to show data—X position, Y position, Z position, dx, dy, and dz. For thermal models, four columns are used to show data—X position, Y position, Z position, and Temperature.
There are three main validation tools in the STAR module, starting with the Load FEA Data Tool, which gives users the ability to check that the coordinate systems are lined up before running the numeric fits. The Alignment Check tool verifies the alignment of the data in the system. The Fit Assessment Tool gives a visual check to show that the FEA model is set up with the same coordinates as the optical or manufacturing model. Rigid body motions can be located at the beginning of the process and pulled prior to the processing. FEA datasets can be aligned easier with the optical surfaces to verify alignment and see the true effect of changes. Coordinate systems can transfer between local and global systems for true comparisons.
Zemax’s literature points out that the STAR functionality requires its own separate license, as well as “an OpticStudio Professional or OpticStudio Premium subscription license.” The module works with OpticStudio Release 21.2 and later. OpticStudio release 21.2 also strengthens other aspects of the software. The Tilt and Decenter tools have an off-axis pivot feature that allows users to take the product and work with inspection or manufacturing fixtures. Hologram industry users get a big boost, with nonsequential functions added for Hologram Lens, Hologram Surface, and Toroidal Hologram objects. These additions should help heads-up display and mixed-reality goggle designers immediately. A new file format, “.PAF,” works with the Path Analysis tool to find and reduce unintended optical paths. The ability to delete current projects and start a new “.ZBD” file is also added with 21.2. It’s a little confusing why that option didn’t exist before now in the software.
FEA Software in the Optics Industry
My experience with FEA software is strictly in the realm of product development, and a cursory search found that optic software or add-ons exist in the Autodesk, NX, Creo, and SOLIDWORKS ecosystems. Searching a little deeper revealed that many additional software is developed solely for the optics industry and their very specific needs and requirements. Starting a new venture with a company using different software than you are using can create problems with file conversions, but those problems generally occur in the beginning of a venture as the two systems learn how to work with each other. The ability to bring your FEA data from any properly formatted source saves the extra step of taking CAD data and porting it to an IGES or STP file before it can be used by another system.
Zemax sees immediate applications for the STAR module across all three of its main application departments: Imaging Optics, Lighting and Illumination, and Lasers and Fibers. It should also be noted that each of these sections of the website features specific applications, user stories, and speculation about what the future might hold. STAR feels like a great tool that will help users save time in an environment that was already built to shave time and development costs from an industry moving at an incredible pace.