Imaging in space: multiple applications, many challenges, one partner
At G&H, we have a long history of developing and delivering precision optical and optoelectronic systems for terrestrial imaging applications, particularly for aerospace and defense platforms, in our US facility in Keene, New Hampshire.
But the Keene team also has a proven track record of creating imaging solutions for use in space – an environment that brings a whole new set of challenges with it in comparison to Earth-based applications.
Here’s a brief explanation of what G&H’s space imaging solutions have been developed to stand up to, together with some quite diverse examples of how they are being used successfully in space missions.
What’s in an imaging system?
Firstly, let’s define exactly what we mean by imaging systems, for both terrestrial and space applications.
Imaging systems combine many different subsystems and components to create complete sensors or cameras that are capable of capturing predominantly moving images. However, the effectiveness of the entire system ultimately stands or falls by the quality of what’s at the very front of the system – the lens and its associated optoelectronics.
These are the all-seeing eye of the imaging solutions that G&H not only develops, but also integrates into the sensors that are, in turn, the nerve center of customers’ and partners’ finished products.
They embody world-leading expertise in optical system design, using best-in-class glass, coatings, and control electronics, in solutions that span the visible to far infrared waveband spectrum.
Imaging on Earth and in space: critical differences
Even in terrestrial roles, the demands placed on imaging systems are exacting and often mission-critical. From defense (target acquisition, sighting, range-finding) to surveillance, intelligence, and reconnaissance, accurate and effective imaging systems underpin many defensive assets on Earth.
In space, however, not only are the applications different (we’ll look at those a little later on), the challenges are much, much greater.
Temperature, shock, vibration, electrical interference, and size, weight, and power (SWaP) limitations – all staple issues in many terrestrial A&D applications, granted – are nonetheless greatly amplified in a space environment, and there are the added difficulties of operating in a vacuum with high levels of radiation ever-present.
To cite just a few examples, thermal stress, for example, can cause damage to lens performance, and has to be offset by careful choice of glass and mechanical mounting in a way that would not typically be necessary for terrestrial applications.
At the same time, extremes of temperature can cause expansion and contraction both in the lenses themselves and in their mountings, leaving the glass under- or over-constrained, and this must be compensated for by special optimization of each lens’s mounting and the thermal coefficients of the materials used. Optimizing the optical design for the operating environment, vacuum conditions, can be critical to the overall success of the system.
Additionally, operating in a vacuum means the system’s components have a tendency to outgas, which can interfere with both optical and electrical processes – so the entire system needs to be constructed using low-outgassing materials.
In short, space imaging systems need to be ruggedized to stand up to the job – but ruggedization is about designing resilience into every component, not just encasing a unit in tough rubber. You can learn more about the process in this recently recorded webinar.
In turn, it also requires an approach that combines extensive pre-project analysis – working with the customer or partner – and rigorous testing across thermal, structural, and optical benchmarks.
Space, after all, is a long way to go to repair a camera, whether it’s the lens system or sensor pack that develops a fault.
Space imaging applications: a G&H strength
When it comes to how space imaging systems are actually used, there is naturally some overlap with defense applications, but G&H’s involvement with many other space imaging projects demonstrates that the potential goes far beyond this.
NASA’s VIPER lunar rover, for example, will use multiple G&H lens systems to enable it, in its 2023 mission, to produce imaging that detects water content on the south pole of the Moon.
Geo-observation of Earth from space, and orbital star-mapping to determine the location of satellites, are both burgeoning space imaging applications, with G&H lens components currently being used by space agencies in both roles.
Interestingly, however, the applications are not confined to long-distance and wide-area applications, and neither are they limited to specific wavebands.
As we speak, G&H-powered imaging systems are in use in the International Space Station for much closer-in work – namely, to help spacecraft dock with the Station – and the G&H imaging system hardware currently in space operates across every waveband.
Built specifically for space
What’s clear from the story we’ve told here is that whilst there are some synergies and similarities between terrestrial and space imaging applications, the differences between them go so far as to preclude the shared use of identical components and subsystems.
Simply put, if you want it to work in space, it needs to be designed for space – and this is where G&H adds unique value to its customers and OEM partners.
This is about more than just technical detail, however. It’s about combining long-established experience and expertise with highest-quality materials sourced or produced either from within the wider and vertically integrated G&H Group or from an established network of suppliers. Controlling the supply chain is key to ensuring consistent quality and availability, greater dependability, and US-based accountability.
Our recently opened, UK-located Optical Systems Innovation Hub demonstrates the emphasis we place on this customer-centricity, and the investment we have made in it, whilst our new and extensive cleanroom facility ensures we have the cutting-edge manufacturing and assembly capability to consistently deliver on the exacting standards of quality that our space customers and partners demand and deserve.
Our US facility in Keene offers a comparable suite of engineering expertise and R&D and metrology hardware and clean room facilities.
Space is big, and the challenges around imaging are many, but G&H is a single port of call for customers and partners looking to innovate across them all.