The uRay, MK-7

An animation of the MK-7 disinfecting a smartphone:

The outbreak of COVID-19 has increased the public’s interest in various chemical and non-chemical disinfection methods. One of the most promising and quickest surface disinfection methods is irradiation by UV-C light which is an existing technology used commonly.

Alongside professional usage, UV-C disinfection is getting more and more attention for personal usage at home or on the go. However, most currently available devices are cheap, unreliable, and often dangerous to use.

We’ve designed a small, hand-held, rechargeable, battery-powered, LED-based UV-C surface disinfecting device which solves the issues with the lower-quality devices flooding the market. Firstly, the device has a UV-C output power of 120 mW which is capable of killing viruses and bacteria in seconds.

Most similar devices are not that powerful.

Observe the early MK-3 before it evolved into the MK-7:

Secondly, our device uses a carefully engineered reflecting sheet, which focuses the UV-C light to a narrow line, increasing the light intensity, hence increasing the disinfection rate. This gives it a focused laser effect.

Thirdly, the device is fitted with numerous safety features which protect the user. An infrared proximity sensor measures the distance between the device and the surface to be disinfected, which acts as an interlock. If the device is held at an incorrect distance, the UV-C light cannot be turned on.

Furthermore, the light emission is stopped as soon as the device is moved too closely toward or too from the surface. An accelerometer and gyroscope continuously track the motion of the device and shuts the light emission down in case of any sudden, unwanted movement. This prevents people (such as children) from waving it around in a way that could hurt people’s eyes.

Finally, we use LEDs which emit visible light in the same direction as the UV-C LEDs. Therefore, they serve as an indicator for the presence of the invisible and dangerous UV-C light. The LEDs were chosen to emit green light since the human eye is the most sensitive for this. Even on a bright day, the green indicating light will be seen, ensuring the safety of the user.