Producer of optical simulation software Optis has announced that the United States Air Force Research Lab's 711th Human Performance Wing, Human Effectiveness Directorate, Directed Energy Bioeffects Division, Optical Radiation Branch (AFRL 711 HPW/RHDO), based in Brooks City-Base, TX, has adopted the company's light and colour simulation software OptisWorks to simulate laser protection eyewear.
The research lab has successfully deployed Optis software solutions to simulate the performance of various manufacturers’ proposed designs of anti-laser eyewear. The Optis software solution enables AFRL to approve or reject a manufacturer’s design for use by military aircrew. Among the reasons for choosing OptisWorks was its complete integration into the SolidWorks CAD program and OptisWorks’ capability to carry out accurate colour simulations.
In order to maximise combat survivability and crew effectiveness, air crews need an effective means of protecting their eyes from the risk of injury from lasers. Traditional laser eye protection (LEP) gives some degree of physical protection by filtering out the undesirable wavelengths of light while still transmitting visible light. However, the disadvantage of these traditional designs is that the colour filters, used to block laser light, can interfere with the air crew’s reading of cockpit instrumentation by altering their whole light environment.
AFRL, with support from optical specialists from TASC, employs Optis solutions for testing two aspects of LEP. Firstly, to analyse geometric coverage of the LEP, they use OptisWorks’ reverse ray tracing techniques, whereby the eye is considered as a source and each ray emitted around the eyewear is deemed to be a possible entry path for a laser. While this is not a physical reality, it is an effective means to determine the coverage area. The only alternative – to determine the infinite possibilities of where a laser in space could be positioned to bypass the eye protection – would be a practical impossibility.
The second challenge faced by AFRL was simulating and analysing how colours appear when seen through the LEP. Using OptisWorks’ advanced colorimetric simulation capabilities and its ability to take into account human vision and a sunglass filter kit, where the special LEP filters are defined, engineers can ascertain the degree of colour change that occurs when a specific element of cockpit instrumentation is viewed through LEP. This enables them to determine whether a pilot will be able to correctly interpret avionic information from displays, warnings, and illuminated controls on the cockpit interface. Correct colour perception is of critical importance in a flight deck, particularly at high speeds and in stressful combat situations.
'By using OptisWorks software we have cut out months of costly, time-consuming human testing and simultaneously improved the reliability of our findings. When we compared simulation results and real measured results the difference was almost zero,' commented Bill Brockmeier, Optical Engineer, Advisory Services (TASC), Brooks Air Force Base, Texas.