A thermometer like no other

Sensor is helping control spread of COVID-19

The protocols at Raytheon Technologies’ campus in McKinney, Texas, are mostly like those in place at office buildings and factories all over the world: employees put on a face mask, badge in, answer a half-dozen questions and have their temperature taken – all, of course, in the name of controlling the spread of the coronavirus.

What’s different about the McKinney facility and at many of the other Raytheon Technologies sites is this: The temperature screening comes courtesy of a thermal camera with an infrared sensor made with technology from Raytheon Vision Systems of Raytheon Intelligence & Space, one of the four businesses that form Raytheon Technologies, in collaboration with Seek Thermal.

The system, called Seek Scan made by Seek Thermal, reads an employee’s skin temperature, and an algorithm converts it to body temperature. At the McKinney site, if the reading is 100.4 degrees Fahrenheit or higher, employees are sent home, asked to call their supervisor as well as a company COVID-19 hotline and advised to speak with their primary care provider. (Temperature thresholds, vary by region and the guidance of local health authorities.)

“It’s not a cure, and the system doesn’t tell you if an employee has the coronavirus, but elevated temperatures are one of the symptoms of the virus,” said Jeff Hamers, Raytheon Vision Systems program manager for Seek Thermal.

The Seek Scan system consists of a thermal camera mounted on a tripod, a reference heat source to ensure its calibration and accuracy, and a Windows PC. The monitor shows a green box around people who they pass and a red box around those who don’t.

“The system is designed to basically plug and play,” said Bill Parrish, Seek Thermal co-founder and chief technology officer. “Seek Scan allows for social distancing. It’s a totally non-contact, non-invasive screening process, eliminating the proximity problem you have with hand-held scanners.”

The system focuses in on the corner of the eye, where readings from tear ducts closely approximate the core body temperature. Parrish said Seek is continuously refining the system, releasing frequent updates.

The system uses a microbolometer, an uncooled thermal sensor, made by Raytheon Vision Systems in Goleta, California. They are similar to the company’s defense-grade sensors that go into Forward-Looking Infrared systems for the military and other agencies.

“Our microbolometer technology is at the heart of system,” Hamers said. “We’ve been working with Seek Thermal for more than seven years, and it’s an important commercial thermal sensor contract to RVS. In those seven years, we’ve supplied them with more than 1.5 million sensors.”

Raytheon Intelligence & Space has more than a 50-year history of Forward Looking Infrared technology, and is one of the world's top suppliers, supporting the U.S. Department of Defense and Department of Homeland Security as well as our allies. The technology is used on land, air and sea, and in space, to provide intelligence, surveillance, navigation and targeting.

Forward Looking Infrared technology is deployed across multiple platforms – from satellites, fixed-wing aircraft, unmanned aircraft systems, helicopters, tanks and military vehicles to hand-held thermal weapon sights and missile systems.

“Over the past 20 to 25 years, we’ve really matured the uncooled bolometer that is a part of Forward Looking Infrared technology, first for military applications,” Hamers said. “That innovation dramatically dropped the cost of manufacturing the sensors, making it affordable for commercial applications such as firefighting since thermal sensors can see through smoke.”

Hamers said commercial thermal sensors are smaller with a lower resolution than those that are manufactured for military applications.

“They still work very well,” Hamers said. “And the demand for them has risen due to the pandemic.”

The initial surge for temperature screeners came from hospitals and nursing homes, but as businesses began to re-opening, orders have been coming in from large manufacturing companies, critical suppliers, and even professional sports teams as well as small businesses including restaurants, supermarkets and retail stores.

“I think that for the airlines and mass transit that you might see systems like this as a permanent fixture,” Hamers said. “I think they’ll be another safety system just like metal detectors at the airport.”