What if there was an entirely unexplored wavelength range that could transform how satellites, aircraft, and ground stations communicate, and the only thing missing was a light source small enough to use? That's the gap QVersion is closing. And with ESA Spark Funding, they're about to hand engineers their first real tool to find out.

The Company: QVersion

QVersion is a spin-out from Aarhus University, founded by researchers with deep expertise in nonlinear optics and photonic integration. Their core technology is based on a process called difference frequency generation (DFG); a method that converts standard, commercially available near-infrared laser light into tunable mid-infrared output.

The results fits on a compact chip that can fit on the tip of your finger. This tiny module produces laser light across the 8–9 µm mid-infrared range with a high degree of tunability and precision. These properties have already proven valuable in non-space applications such as gas detection, environmental monitoring, and industrial process control.

Now, with their ESA Spark Funding project, QVersion is adapting that same chip-scale platform for a very different challenge: optical communication links that must travel through the atmosphere between satellites, aircraft, high-altitude platforms, and ground stations.

The Challenge: A Spectrum Left Unexplored

Long-distance communication between space and Earth relies almost entirely on radio-frequency (RF) technology. RF systems are mature and dependable, but they have real limits. The radio spectrum is increasingly congested, available bandwidth is finite, and signals can be disrupted by interference or deliberate jamming.

Free-space optical communication is a compelling alternative. It supports far higher data rates, is more directional, and is much harder to intercept. Most optical systems today operate at visible or near-infrared wavelengths, where hardware is widely available. But these shorter wavelengths come with their own drawbacks: sensitivity to atmospheric conditions and strict requirements for precise pointing between terminals.

The mid-infrared range, around 8 to 9 micrometres, sits within atmospheric transmission windows that could offer more favourable propagation for space-to-ground and space-to-air links. Despite this potential, the band has seen almost no practical exploration. The reason is simple: no compact, tunable, system-compatible light source has existed in this range. Without a usable source, engineers cannot test whether mid-infrared optical links would actually outperform existing approaches. QVersion is about to change that.

The Spark Funding Project: WINDOW

QVersion's ESA Spark Funding project is called WINDOW — Wavelength-selective Integrated Nonlinear Devices for Optical Wireless links.

Over 12 months, QVersion build and validate a laboratory breadboard based on their chip-scale platform, demonstrating stable, tunable mid-infrared emission across the 8–9 µm band. The team will also engage with stakeholders across the space and photonics sectors to validate the technology's relevance and sharpen their value proposition for space communication applications. The goal by the project's end: a working mid-infrared source that researchers and engineers can use to begin testing communication concepts in this wavelength range, for the very first time.

Why This Matters: Unlocking a New Design Space

What matters most about WINDOW is not just the device itself, it's what it unlocks. Today, engineers designing optical links for space and near-space applications have no practical way to experiment with mid-infrared concepts in the lab. Their design choices are constrained by what sources already exist, not by what the underlying physics might allow. QVersion's breadboard changes this entirely. ‍

"If it works on Earth, use it for space."

That's the logic of ESA Spark Funding. and QVersion is opening a window that no one has been able to look through before

QVersion is one of four companies currently supported through the ESA Spark Funding programme in Denmark, managed by ESA Technology Broker Denmark at DTU. Spark Funding provides up to €75,000 in co-funding for companies transferring proven non-space technologies into space applications.

Is your company's technology ready for space? Find out more about ESA Spark Funding →www.spaceventures.dk/companies/spark-funding