NUI Galway lab and Silicon Valley firm use light to get under the skin

A fingerprint reader that can see below the skin and new ways to spot small blood vessel damage caused by diabetes are just two of the applications that could come from research under way at NUI Galway.

Prof Martin Leahy of NUIG has hooked up with a Silicon Valley start-up called Compact Imaging to develop miniature, low-cost optical sensor technology. The hope is the sensor could become a standard feature in smartphones and smartwatches, says Leahy who is chair of applied physics and director of the Tissue Optics and Microcirculation Imaging Laboratory (Tomi) at NUIG .

The California connection is via Don Bogue, chief executive of Compact Imaging. His company owns proprietary IP and holds a battery of patents on it, while Prof Leahy’s team is developing the technology in to a new way of looking at things.

The original collaboration agreement was signed in 2012 and extended last year. On October 14th this year, a second investment in Leahy’s lab by Compact Imaging was announced.

The technology is called optical coherence tomography (OCT) and was developed for studying the surface of the retina and to look at blood vessels from the inside. Compact Imaging came up with a way to reduce the size of the chunky early technology 100-fold. This also meant the cost came down. The company patented the technology and Bogue began looking for a research partner to take things forward.

“We had a need for a specific set of skills and we were talking to people at UC [University of California] Davis and they said the person you need to talk to was Martin Leahy. We contacted Martin and he was doing work on OCT which our company was also developing,” says Bogue.

Original OCT and the company’s own product MRO (Multiple Reference OCT) are a little bit unusual for biological imaging. “We use light in the same way that ultrasound uses sound to image below the surface,” Bogue says.

Fine resolution

An ultrasound signal is sent into the body and sensors pick up the sound bounced back to capture images under the skin. The sensors under development in Galway do something similar, sending a light signal into the skin to map structures underneath. While ultrasound allows you to image deep below the surface, the resultant image is of relatively low resolution and can be difficult to read.

The OCT light technology can only penetrate one or two millimetres below the surface, but the resultant image gives extremely fine resolution so the technology sees everything that is there in ultrafine detail. A few millimetres isn’t very much but is more than enough to provide a highly useful device. One early application was to use it as new kind of fingerprint reader that could not be tricked.

“We have been able to see the tiny blood vessels that supply the cells that make the ridges of your fingerprint,” says Leahy. “We have used that to show those little blood vessels follow the pattern of the fingerprint on the surface and this is very difficult to fake.”

He sees other applications for the technology in non-destructive testing, in uses where fine details in specialised surface coatings need examination.

There is also huge potential in healthcare. Over time diabetes causes damage to the very fine capillaries in the extremities and in the retina and this system could help to image the level of damage.

“In practice what is important is to see deep enough to have a resolution good enough to see what you need to see. And you need to get the equipment out to the point of care,” says Leahy.

All kinds of possibilities open up if they can bring the technology down further in terms of size and price.

“What we are doing is taking OCT technology in its conventional form which is as large as a steamer trunk and making something the size of a wristwatch. To do that we needed the expertise available in Martin’s lab,” Bogue says.

Diagnosis

They want to get the cost of the sensor needed to take the image down from €900 to less than 50 cent, with a very specific purpose in mind.

“Lots of people have smartphones. If you put the technology into that, then lots of people can use this for biometrics and diagnosis and can deploy diagnosis much more quickly,” says Leahy.

Neither Leahy nor Bogue realised there was a secondary advantage to doing the research in Ireland. They had heard nothing about the “knowledge box” arrangements for profits derived from research conducted here and announced in the budget. This would see their tax on profits drop to just 6.5 per cent.

Galway is making good progress, hence the fresh investment in the lab from Compact Imaging. Prof Leahy is hoping for additional support from other quarters.

“We are hoping Enterprise Ireland or Science Foundation Ireland will make some investment as well. The knowledge box is more of a thing for Don Bogue on the company side,” says Leahy. “We feel they have been persuaded you can do research in Ireland.”