DKK 42 million for sustainable chip-based spectrometers

In a new four-year Grand Solutions project—supported by Innovation Fund Denmark with DKK 25 million—DTU and four companies will join forces in a consortium called NEXUS to develop the next generation of ultracompact spectrometers based on chip technology:

"We will quite simply make spectrometers in a radically different way that will make them both inexpensive and sustainable," says the originator of the new Innovation Fund Denmark project, Associate Professor Søren Stobbe from DTU Fotonik. He continues:

"In NEXUS, we will develop the nanotechnology and the chip technology, as well as the modules that will be used to integrate the spectrometers in industry already during the project. In short, we will make it possible to perform measurements in places where you cannot measure today. And because we can make the spectrometers small and inexpensive, it can also be good business for companies to choose the most environmentally friendly solution."

^{A spectrometer is an instrument that can measure a spectrum—in this case an optical spectrum—which, in layman's terms, is the colour composition of light. The NEXUS project will build a spectrometer on an ultracompact chip. It functions by splitting the unknown light into two routes of variable length and then interfering it again. Figure and text: Marcus Albrechtsen.}

Spectrometers to reduce waste at dairies

To begin with, NEXUS' spectrometers will make a difference for dairies.

Dairies need spectrometers to measure the contents of protein, fat, and water in their milk. But the spectrometers currently available on the market are large and expensive, which means that the dairies only have a very limited number of them. So when, for example, the dairies are to produce a new batch of semi-skimmed milk, they rinse the pipes with milk to be sure of what they have in the pipes. This means that they send around 10,000 litres of milk directly into the sewers every day. This could be avoided if spectrometers were instead installed to measure what is in the pipes.

Jacob Riis Folkenberg—Vice President of Technology at FOSS, which makes food production equipment—is therefore convinced that the new optical spectroscopy technology has the potential to revolutionize the market:

"In addition to being a waste of time and energy, the 10,000 litres of milk going to waste everyday also has a fairly high market value. If you can get the price of a spectrometer down, this will quickly turn into a really good business case for the dairies. We estimate that there is a market potential of three billion Danish kroner at the dairies alone," he says.

The core of the NEXUS project is DTU's patented chip technology.

"We have a prototype that works, but we don't yet have the spectral resolution we need," says Associate Professor at DTU Fotonik, Søren Stobbe, and continues:

"We need to develop a lot of stuff in the chip, and it must then be built into the whole technology that surrounds it. For it's one thing to make a chip. But—in reality—a large part of the work is to integrate the chip with the surroundings."

While DTU Fotonik is responsible for the development of the chip, the companies Beamfox Technologies ApS and ELIONIX INC will develop methods for nanofabrication of the chip. Ibsen Photonics A/S makes the modules in which the chip will be integrated, and FOSS makes the food production probes in which the modules will be installed and which can be used at the dairies.

Wind turbines, aircraft, and health monitoring on the mobile

The NEXUS project starts with the dairies, but the technology will also be relevant in many other contexts.

"The ultimate vision is to be able to make spectrometers so small and inexpensive that it can, for example, be worthwhile to build them into mobile phones. The spectrometer will be able to make a kind of primitive blood test, which could give you an indication of whether you need to see your doctor," says Søren Stobbe.

"Another example is so-called optical interrogation monitors, which can be used to measure and predict the behaviour of large mechanical structures. They can be built into a bridge, a wind turbine blade, or an aeroplane wing, where they will then monitor whether the material begins to give off some strange vibrations. The area of application for spectrometers—if you can make them in this low price range—is gigantic."