Optics & Photonics: Accelerating the Technologies Protecting Lives in Modern Conflict

From the laboratory to the field: Is defense entering a new photonics era?

Stratos Kehayas, PhD

Five years ago, we identified aerospace and defense as one of the markets where photonics was poised to make a significant impact¹. Robust sensing and imaging, communication in RF-denied environments and navigation without access to GPS were emerging as critical challenges where photonics could offer unique solutions.

The challenges have not gone away. Quite the opposite.

Geopolitical tensions, rapidly evolving threats and the proliferation of relatively inexpensive autonomous systems are forcing defense organizations to reconsider both the technologies they deploy and, perhaps more importantly, how quickly they can deploy them. That pressure is reflected in global military expenditure, which reached approximately $2.9 trillion in 2025².

Historically, aerospace and defense have been characterized by long technology development and qualification cycles. That is understandable. Equipment must operate reliably in some of the harshest environments imaginable, from vibration and extreme temperatures to radiation, contamination and shock. Failure is simply not an option.

When GPS Disappears: Photonics and the Future of Navigation

Modern military systems depend heavily on precise position, navigation and timing (PNT).

Aircraft, ships, ground vehicles, autonomous platforms and communications networks all rely, directly or indirectly, on accurate timing and positioning information. GPS has transformed these capabilities, but its ubiquity has also created a vulnerability.

In a contested environment, what happens when GPS is jammed, spoofed or simply unavailable?

The answer will not be one technology. Resilient PNT is likely to be built from multiple complementary technologies, and optics and photonics already provide much of its technological backbone.

Fiber-optic gyroscopes and ring-laser gyroscopes have long provided highly reliable inertial navigation. Their attraction is straightforward: no reliance on an external radio-frequency navigation signal and, in the case of optical gyroscopes, extremely precise measurement of rotation using light.

But the next frontier is particularly interesting.

Advances in quantum sensing and optical atomic clocks are opening the possibility of maintaining extraordinary levels of timing and navigation accuracy for extended periods without continuous access to GPS. R&D programs like the Innovate UK CASPA project established the technological foundation for practical ultrastable lasers and atom traps³.

More recently, advanced atomic and optical clock technologies have begun moving toward deployment in space. Galileo Second Generation satellites will carry six improved atomic clocks, while European programs are developing optically pumped, optical and ion clocks for potential future flight, illustrating the transition from laboratory-based timing technologies toward deployable space systems⁴.

This is an important distinction. The question is no longer simply: can we navigate without GPS? Increasingly it is: how accurately, for how long, and in what size of system can we do it?

Moving optical clocks and quantum sensors out of controlled laboratories and onto deployable platforms introduces an entirely new set of engineering challenges.

Directed Energy: When the Laser Becomes the Defensive System

Perhaps nowhere is the transition from photonics research to operational capability more visible than in laser directed energy. The DragonFire laser directed energy weapon, developed through the UK Ministry of Defence and industry, has progressed from technology demonstration to planned operational deployment aboard a Royal Navy Type 45 destroyer. Following successful trials against aerial targets, the program’s introduction into service was accelerated by five years, from 2032 to 2027⁶.

That five-year acceleration is significant. It illustrates the broader shift taking place across defense: the question is increasingly not whether high-energy laser technology can work, but how quickly it can be engineered, qualified, manufactured and integrated onto operational platforms.

Laser systems offer several fundamentally different characteristics from conventional kinetic interceptors: energy can be delivered at the speed of light, engagement can be highly precise, and the effective cost per engagement can potentially be reduced once the system has been deployed.

And this is where the next photonics challenge begins. Increasing laser power is only part of the equation. As directed energy architectures become more sophisticated, they will demand increasingly precise and responsive ways of controlling light. Emerging electro-optic platforms such as thin-film lithium niobate (TFLN), offering the potential for high-speed and efficient optical modulation, could become an important enabling technology as these systems evolve.

The next generation of directed energy systems will therefore depend not simply on generating more laser power, but on the ability to generate, control and manage that optical power reliably in an operational environment.

That distinction matters. A laser demonstrated under controlled conditions is one thing. A system that maintains beam quality and optical performance after vibration, thermal cycling and prolonged operation aboard a moving platform is something entirely different.

This is where the photonics supply chain becomes critical. High-power fiber components, precision optics, high laser-induced damage threshold coatings, beam-control technologies and rugged opto-mechanical assemblies are not peripheral to the system. Collectively, they determine whether laboratory performance can become operational capability.

Directed energy therefore illustrates a wider shift occurring across defense: the underlying physics has increasingly been demonstrated; the next challenge is engineering, integration and scalable manufacture.

Seeing More: The Evolution of Infrared Electro-Optical Systems

For decades, electro-optical/infrared (EO/IR) systems have enabled operators to see beyond the limits of the human eye. Once regarded as specialized technologies, they are now becoming integral to defense and security architectures as the need for greater situational awareness - and better protection of personnel on the battlefield and in urban environments - continues to grow.

Different infrared wavebands provide different information. SWIR can offer valuable imaging performance in conditions where visible systems struggle and can exploit reflected light signatures. MWIR provides strong thermal imaging capability and is particularly valuable for detecting and discriminating objects over extended ranges.

Increasingly, the question is not necessarily SWIR or MWIR. It is how information from multiple spectral bands can be combined to improve situational awareness.

That creates a demanding optical-design problem. Broadband, multi-band systems must correct higher-order chromatic and geometric aberrations across wide spectral bands, often while meeting stringent size and weight constraints. Work undertaken by our optical design team demonstrated how a fast, wide-angle catadioptric architecture could provide a compact, well-corrected lens for broadband imaging applications⁷.

Translating that optical performance into a deployable system introduces further demands in specialist materials and coatings, precision alignment, ruggedized opto-mechanical design and environmental resilience.

Beyond the optical hardware, another transformation is taking place.

Artificial intelligence and increasingly capable onboard processing are changing what happens to the photons after they reach the detector. This transition is already visible in emerging defense sensing programs, where SWIR imaging is being combined with AI and machine learning to enhance target detection, identification and tracking, including applications such as counter-UAS⁸.

Yet even the most advanced AI can only interpret the information the optical system captures. Better algorithms cannot recover information that was never collected in the first place.

High-quality optical design, appropriate spectral selection, coatings, detector integration and image stability therefore remain fundamental to the performance of the overall system. This becomes particularly important as sensing moves across domains.

Environmental requirements vary significantly by platform. Ground vehicles require ruggedized imaging systems capable of surviving severe shock and vibration, while airborne systems introduce stringent size, weight and power constraints. Across these applications, optical assemblies may need to be sealed, athermalized and ruggedized to maintain alignment and imaging performance under demanding operating conditions⁹.

Space-based systems add radiation exposure, limited power availability, launch loads and severe thermal cycling, requiring radiation-tolerant materials and carefully engineered and ‘toleranced’ optical and opto-mechanical architectures.

The environment changes. The underlying requirement does not: collect more useful optical information, from further away, with greater confidence.

The Common Challenge: Moving from Exquisite Technology to Deployable Capability

At first sight, a quantum optical clock, a high-energy laser and a multi-band infrared imaging system appear to have relatively little in common. Look beneath the application, however, and the engineering challenges become remarkably familiar.

All three demand high optical performance within increasingly stringent size, weight and power constraints. All must operate reliably in harsh environments. And all are moving from specialized technologies toward capabilities that defense organizations increasingly want to deploy at scale.

Performance alone is therefore no longer enough. The next generation of defense photonics must combine performance, reliability, ruggedization, manufacturability and scale.

Achieving that requires closer integration across the supply chain. Component manufacturers, photonics specialists, optical system designers and defense primes need to work together earlier, because decisions made at component level increasingly determine performance at system level.

The future belongs not simply to better components, but to better integrated photonic and optical systems.

Optics & Photonics as Enabling Technologies for Protection

When we considered these markets in 2021, many of these technologies were still emerging¹. We argued that robust sensing and imaging, communication in RF-denied environments and navigation without GPS would become key challenges where photonics could offer unique solutions.

Five years later, what we saw coming is no longer simply on the horizon. It is happening.

Quantum-enabled navigation is moving beyond the laboratory. Directed energy systems are progressing toward operational deployment. Multi-band infrared sensing is being combined with increasingly sophisticated processing and AI to enable advanced intelligence, surveillance and reconnaissance.

References

1. Kehayas, Efstratios, PhD, Photonics Emerges Stronger from the Pandemic, Proving its Robustness and Resilience Against Market Disruptions, G&H Insight, June 2021
2. Stockholm International Peace Research Institute (SIPRI), Trends in World Military Expenditure, 2025, April 2026, https://www.sipri.org/sites/default/files/2026-04/2604_milex_2025.pdf.
3. E. Kehayas, “Photonics in Satellite and UAV Laser Communication and Sensing”, Electronics Warfare Technology Conference (EWTC), UK Defense Academy, Shrivenham, UK, 18–20 June 2019.
4. EU Space Support Office, “OBSERVER: Precise Timekeeping with Galileo”, 20 August 2026. https://eu-space.europa.eu/news/observer-precise-timekeeping-galileo.
5. Defense Advanced Research Projects Agency (DARPA), It's About Time for Quantum Manufacturing, 6 August 2026, https://www.darpa.mil/news/2026/its-about-time.
6. UK Ministry of Defence, Boost for Armed Forces as New Laser Weapon Takes Down High-Speed Drones, 20 November 2025, https://www.gov.uk/government/news/new-procurement-rules-help-rapid-fitting-of-military-laser-to-royal-navy-ships.
7. Pollica, Naomi J., and Christopher C. Alexay, “Wide-Angle Catadioptric Optics for Broadband Applications,” Proceedings of SPIE, Vol. 8704, Infrared Technology and Applications XXXIX, 2013, https://doi.org/10.1117/12.2018915.
8. U.S. Army SBIR/STTR, Development of Polarimetric SWIR Camera System with AI/ML Capabilities to Counter Swarming UAVs, 19 April 2023, https://armysbir.army.mil/topics/development-polarimetric-swir-camera-system-aiml-capabilities-counter-swarming-uavs/.
9. Pause, P., “The Sealed, the Athermaled, and the Rugged: The Wild West of Modified Opto-Mechanical Design,” Proceedings of SPIE, Vol. 10914, Optical Components and Materials XVI, 1091423, 2019, https://doi.org/10.1117/12.2509790.