Using light to develop guidelines to manufacture quality face-masks
By Krishnakumar Chullipalliyalil
Have you ever wondered when your car is reversing, how the proximity sensor works before you knock something down? Or how the burglar alarm in your house works? What if the same technology of these gadgets could be used to check how good your face-masks are?
My line of work is known as optical instrumentation. The term ‘optical instrumentation’ refers to the branch of technology that builds more or less sophisticated instruments that make use of an optical phenomenon. These optical phenomena can include things you see every day. For example, consider the case where you are given tags at a night party that glow under the bathroom UV light- The phenomena that you observed, or the glow- is called fluorescence. Another example would be when you see dust particles glowing when the early morning sun glazes through the window- this is what we call scattering. When you were a kid you might have wondered about the rainbow appearing on the ground when oil is pilled.
So, what do I do ? I basically develop ideas for making instruments based on these so called optical phenomena. Most of the instruments are meant for the applications of sensing and product manufacturing. Sensors can be anything, basically ranging from sensors that help check leaks in industry, to the ones that you use in daily life like that I mentioned in the beginning, the proximity sensor of your car. I work at Munster Technological University, formerly known as CIT. The research group I work in is called CAPPA- Center for Advanced Photonics and Process Analysis. CAPPA is a research centre conducting both applied and fundamental research for applications in areas as diverse as telecommunications, medical devices, food and pharmaceutical manufacturing. In CAPPA we have two main foci: Innovation for Industry – provide light application based solutions to companies in sectors such as medical devices, food and pharma, on scales from short-term consultancy to multi-year collaborative projects and also advanced Research – to conduct internationally recognised academic research. This is supported by grants from agencies such as Science Foundation of Ireland, Higher Education Authority (HEA) and the EU.
Optical phenomena can include things that you see in daily life. For example, consider the case where you are given tags at a night party that glow under the bathroom UV light- The phenomena that you observed, or the glow- is called fluorescence.
Face masks have played an important role in reducing the spread of COVID-19. The latest light based project that I did, is a project for recognising a guideline for mask preparation. There are certain specific guidelines on the use and quality of the masks used according to the European Committee for Standardization (CEN). My colleague, Dr. Steven Darby is a member of CEN. Dr. Darby and I worked to develop a laser based technique to test the efficacy of different types of face masks that are currently in the market. Dr. Niall Smith, head of research in MTU and Blackrock Castle Observatory (BCO) Cork, has played an important role in procuring the funding for the project from the Science Foundation of Ireland. The idea was quite simple: What if we can just visualise the leak of a mask, just by shining more light? It looks like the photo below. The results we got were outstanding.
A laser (the same thing that is used in the sensors that I mentioned in the beginning) is used to shine at the particles that are leaked out of the mask- that includes particles from our breath that is transmitted through the masks and also leaked from the sides of the masks. The phenomena that I mentioned earlier, called “light scattering” helps in illuminating the leak out of the mask- something that would be hard to visualize with our naked eye. We simulated a human breath made out of water vapour by placing an artificial lung inside a medical mannequin (they are often used in the medical field for academic purposes). We illuminated the breath that is coming out of the mouth and nose of the mannequin with two lasers (We used a blue laser, and a red laser. How often have you seen blue lasers!!), and we kept a high-speed motion camera next to it.
You can clearly see the leak that is originating from the mouth and nose with a single breath and of course, one in which the mask is not covering the nose properly. This was a clear demonstration of proper use of masks. We submitted one of the images that we goto the Science Foundation of Ireland, and we won the Research image of the year award! MTU was kind enough to place banners of the same throughout the campus to increase awareness of the importance of wearing masks.
This work was completed around the middle of 2020. We had to be careful not to share common spaces too often because we had limited access to the lab. It was difficult, but we made it work by scheduling labs ahead of time and meeting online.
I’d like to leave you with a call to action and encouragement. What we’re all going through—these are, indeed, difficult times. But let us not give up hope. Let us also take a moment to recognize our fighters who have been working tirelessly on the frontlines. We’ve all had to deal with rough patches, but we must maintain our faith.
WE SHALL OVERCOME !
I basically develop ideas for making instruments based on optical phenomena.
