Photon Engineering FRED FAQ

Frequently Asked Questions

What is "optical engineering software"? How is it different from lens design software?
“Optical engineering software” picks up where lens design software leaves off. With optical engineering software, the analyst merges the optical elements with the mechanical components to build a complete, integrated model. Frequently this is the first time in the product development process where the optical and mechanical parts are together in the same model, and so mismatched elements, incorrect separations and/or locations, inconsistent dimensions, “the same lens has to be in two places at once”, etc are readily identified.

This integrated model serves as a basis for performing “real world” analyses of the performance of opto-mechanical system. For example FRED is routinely used to analyze and quantify:

•		Formation of ghost images in molded plastic lenses
•		Formation of lens-damaging ghost images in laser systems
•		Stray light levels in sensors
•		Interference effects in coherent systems
•		Irradiance and intensity uniformity in illumination systems
•		Appearance of images at different wavelengths and under various types of illumination
•		Signal levels, throughput losses
•		Unexpected “glint” (specular) paths (sometimes called “sneak paths”) that create image artifacts
•		Contrast levels in projector systems
•		Effectiveness of baffle, light shields, surface treatments, etc to improve contrast
•		Thermal self-emission levels in MWIR, LWIR systems

No product, no matter how trivial, should be released for prototyping without being assessed by FRED optical engineering software!

Why is it important to work in a 3D virtual prototyping environment?
It's critical to your finished product to conceptualize and capture the entire optical/illumination design early in the design process. Good designs are built from the ground up with the intent of manufacturing a product. The only productive way to do this is by creating a 3D CAD model that takes into account not only the optical elements but the mounting and mechanical structure that may obstruct or interfere with the light propagation path. The ultimate power of virtual prototyping is the capability to test a total system concept quickly without spending time and costs to cut metal through multiple iterations. FRED's 3D WYSIWYG (What You See Is What You Get) CAD interface is perfect for virtual prototyping.

Why use a 3D CAD environment, aren't spreadsheet based products faster?
If you are trying to use a spreadsheet interface to do 3D virtual prototyping check yourself with this important question? When I need to manufacture my new concept, will my CAD department use a 3D CAD interface or a spreadsheet-based product to create the manufactured model? It might be faster in some instances to work in a 2D spreadsheet environment, but you are sacrificing detail required to fully manufacture the assembly and you are losing the 3D visual understanding of how parts are placed in regard to each other spatially. Using a spreadsheet interface is usually a clunky affair that has problems providing the full visual 3D global picture. Instead, what you usually see are "snapshots" of 2D sections that prevent you from easily finding problem areas in 3D space that need to be addressed before creating the finished product.

Why is FRED superior for exporting CAD models?
Spreadsheet based products are known for exporting poor CAD models. This is mainly due to the fact that most of these products use exact surface equations to model optical components and these surfaces are exported as wireframe models or second order patches of higher ordered surfaces. These models are great for fast raytracing speeds and effective for reducing optimization time, but real surface data is needed to convert these surfaces to the NURB information that CAD systems need. The amount of time for an engineer to convert models from spreadsheet surface based systems into a complete manufacturable CAD model may take more time than the entire time it takes to do the optical design. Isn't it a better idea to use a 3D CAD program that exports exact solid and surface geometry at manufacturing tolerances which FRED does to alleviate this tiresome and problematic step?

Further, FRED exports both the opto-mechanical subassemblies and a full ray set detailing the footprint of the optical ray set or beams through the optical assembly. This feature is perfect for checking ray set or beam impingement on mechanical structure through the optical path.

Other optical software is very expensive. Why is FRED so inexpensive?
Does the low cost mean that FRED is less capable?
Photon Engineering is a focused business with two lines of business: consulting services and FRED. We do not divert our resources into unprofitable business pursuits nor do we have a “top heavy” management. By concentrating on what we do best, we can keep the development costs down and the value to our customers up.

FRED is comprehensive, full-featured optical engineering software in daily use by our own consulting group, national laboratories and universities, major aerospace and defense contractors, product development companies, and consultants worldwide. Compare its features with those of any other software on the market and you’ll see that FRED is cost-effective and capable!

Other optical software is available in several different editions and/or with several options.
Are there different editions of FRED? Are there any add-ons or extra features to buy?
From the beginning, we planned to market one, comprehensive, all-inclusive edition of FRED; with no add-ons or extras to purchase! Recently, however, several of our larger customers requested an edition that traces rays on multiple processors using a multi-threaded approach and uses a network license. This ongoing development is expensive, so instead of increasing the price of FRED for everyone, we decided to create a FRED Turbo edition specifically with multi-processor support and networking capability for those customers and potential customers who need this type of horsepower. Our FRED Standard edition will incorporate the multi-threaded ray trace for up to two CPU cores shortly.

Our business philosophy is not to “nickel and dime” our customers with necessary add-ons and extra features that drive the purchase price upwards. We believe that it is misleading to attract potential customers with a low initial price and then make them pay extra for the features they need to get their job done. But we also understand that some customers may need certain high power features and that not all customer's needs are the same, therefore we have created two editions of FRED.

How often are FRED updates made available?
FRED is under constant development and some users simply can’t wait to get the “latest and greatest“ version of FRED. For these users, we put an “intermediate” version of FRED onto our website for download on a regular basis. These intermediate versions have been tested internally but new features may not be completely implemented.

Twice a year we release the “major” FRED updates. These versions have been tested internally and by customers downloading the intermediate versions. All new features are fully functional.

Our standard policy is to notify our customers by e-mail that the intermediate and major releases are available for download. Some customers, because of security reasons or IT requirements, request that a CD be mailed to them instead.

Does Photon Engineering do custom FRED development?
Yes! Photon Engineering has completed and released several new features that have been requested and funded by customers.

However our standard policy is that all new features are immediately available to all of our customers; we do not generally develop “exclusive” FRED features.

What does the name “FRED” stand for? Is FRED an acronym?
Well, the truth is that the name FRED is just a name; it is not an acronym or abbreviation! FRED was the original development name of the software when Steve and Rich started working on it in the early 1990’s. (Rich had previously worked with an engineer who used the name FRED the way mathematicians use “x” as the name of a variable. Something “clicked” and Rich started using FRED as the name for anything that didn’t have a name!) When it came time to release the first commercial version of FRED in April 2001, we couldn’t agree on a better name and so the FRED software development project became the FRED Optical Engineering Software.