Breakthrough Tech Can Check Body Temperature Using A Smartphone Camera

Restrictions due to the pandemic are easing in many states, but we all remember having our temperature checked to get into many businesses during the pandemic. The temperature checks were performed because COVID-19 was known to cause an increased temperature and often signaled an infection the person might not know they have. Researchers have developed a new technology that's able to check body temperature using a smartphone camera.A team of researchers led by Dr. Won Jun Choi at the Center for Opto-Electronic Materials and Devices at the Korea Institute of Science and Technology (KIST) has developed a thermal-imaging sensor overcoming problems with price and operating temperature limitations. The sensor developed by the team can operate at temperatures up to 100 degrees Celsius without a cooling device.

Researchers believe the breakthrough will be more affordable than standard sensors currently on the market and could pave the way for its application in smartphones and autonomous vehicles. To be integrated with hardware inside smartphones and autonomous vehicles, the sensors have to operate stably at high temperatures of 85 degrees Celsius and 125 degrees Celsius, respectively. Conventional thermal-imaging sensors require a cooling device to operate in those thermal conditions.

The problem is that the cooling devices required for current thermal sensors are expensive. Despite the cost, the cooling devices don't make the sensors suitable for operation at temperatures as high as 85 degrees Celsius. Those limitations mean thermal imaging sensors haven't been suitable for application in smartphones or autonomous vehicles.

The new sensor was developed using a vanadium dioxide film that is stable at 100 degrees Celsius. The device can detect and convert infrared light generated by heat into electrical signals eliminating the need for cooling devices. Traditionally, cooling devices account for over 10 percent of the cost of a thermal imaging sensor and consume significant amounts of electricity.

Researchers say their new sensor could obtain the same level of infrared signals at 100 degrees Celsius as it can't room temperature. Heat signatures are also detected with three times more sensitivity and converted into electrical signals. The resulting sensor shows an ability to capture thermal images at 100 frames per second with a response time of around three milliseconds at 100 degrees Celsius, which is 3 to 4 times faster than conventional sensors.