Tougher than Nails: How G&H Prioritizes Ruggedization for Its SWIR, Off-the-shelf Lenses
Commercial off-the-shelf (COTS) optical systems used in land, air, and maritime applications are usually the product of choice for those wanting to reduce investment costs and lead time. But the affiliated risk strategy for such parts may deter potential interest, especially when considering the performance required for complex solutions. At G&H (LON:GHH), we understand the need for top-tier optical components when designing SWIR lenses for harsh environments. In fact, one of the main priorities for our engineers involved in world-class optics manufacturing is ruggedization.
As mentioned in the SPIE article “Ruggedized optics for harsh environments” by Kyle Firestone, “Ruggedization options for imaging lenses are as numerous as the applications for which they are used. As automation continues to improve, imaging systems will continue to be integrated into harsh or extreme application environments. As such, advances in ruggedization technologies are extremely important and have never been more relevant.” Our team has reached the same conclusion regarding the importance of designing and testing for a rugged optical system. In a world that is powered by increasingly complex technology, demanding applications are expected to guarantee both performance and survivability.
The G&H Design Approach for Tough Lenses
For example, take an optical element that is embedded in an industrial image processing system such as a FireAnt™ lens, one of the main shortwave infrared continuous zoom solutions at G&H. The element will function according to its peak performance parameters only if it is protected from interfering forces. External factors that could impact its outcome quality include extreme temperatures, shocks and vibrations, pressure, dust and particles, moisture and humidity, electromagnetic interference, and even explosive gases. Such harsh conditions can be pre-estimated in the design phase of the optical solution when deciding on the ruggedization framework that will be applied.
The G&H approach when designing a high-resolution SWIR zoom lens requires a layered methodology:
- The optical and opto-mechanical design perfects the optical element for performance and durability;
- Advanced materials and coatings are chosen based on SWIR-specific performance specifications;
- Precision control electronics are involved for repeatable performance across variable environments.
This approach has been developed and optimized based on thousands of successfully qualified case studies in fields like aerospace and defense, security and surveillance, and industrial applications.
G&H’s Ruggedized Optical Systems Made Ready for Action
Ruggedization starts with ensuring the right optical materials are selected during the design phase. Proper care must be given to the aspect ratios of the lenses, including edge thickness, to be able to guarantee that the materials survive more dynamic environments. Once the optical design phase is completed, the opto-mechanical engineering utilizes mounting techniques to limit high-stress concentrations on the optical elements. This careful distribution is essential because forces that concentrate in small areas have a higher chance of deforming lens surfaces, misaligning important optical elements, or even causing damage over time, thus degrading the overall lens performance. As the design moves forward, it is evaluated using Finite Element Analysis (FEA) for robustness of the application.
For example, the G&H FireAnt Series™ is tested by our engineers through an extensive Finite Element Analysis (FEA) process using systems such as SolidWorks and ANSYS. Within this framework, our team analyzes both single and dual-mount configurations under simulated shock loads across all three axes in the standard Cartesian coordinate system. By simulating shock loads along all three axes, engineers can ensure that the lens mounts can effectively handle dynamic forces from any direction — whether the force strikes laterally, vertically, or along the direction of the optical path. In both configurations, the stresses remained well below the yield strength of 6061-T6 aluminum. This means any FireAnt™ lens can be exposed to shocks and still stay aligned, showing no tilt, no decentering, and undergoing no performance drop.
That way we can assure the highest in-band performance possible in terms of transmission, resolution, and durability.
Finding the Right Ruggedization Balance
Focusing on lens performance against shock and vibration requires a different set of testing considerations than those used in the case of extreme temperature variations. As mentioned by G&H Engineering Director Troy Palmer, “We want the optics delivered by G&H to be constrained enough to survive shock and vibration, but not so tight that they’re strained during thermal expansion. That’s where FEA and real-world test feedback come in.” A Goldilocks ratio needed to be found when dealing with this commonly met combination of active factors on the lens system. As a result of extensive R&D, our robust testing and validation ensure survivability under all major interferences such as extreme temperature, vibration, and shock by including:
- Passive and active athermalization;
- Strategic mount placement around the lens’s center of gravity;
- Stress-tested boards, motors, and encoders rated for vibration and temperature.
The results of this intensive testing environment encompass the following parameters:
- Operating temperature (°C): -30° to +80°C
- Storage: -54°C to +100°C
- Shock/vibration per applicable specification
- AR coating (nm): High-durability per MIL-PRF-13830
Overall, ruggedization is a process that aims to align expectations for the performance and precision side of the optical design with the realities of harsh operational environments. As we continue to push the limits of technology in sectors that demand both top-tier quality and durability, robustly built optical systems become integral to achieving reliable, high-impact results.
Optical systems such as the G&H FireAnt Series™ stand at the edge of what is physically possible with high-definition optics, waiting to be embedded in the next generation of optical application.
Take a look at the G&H FireAnt Series™, or join as right now at the DCS G&H at Booth #811 to see how we’re advancing shortwave imaging—and photonics technology more broadly—through rugged innovation and precision design.
FireAnt demonstration video
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