Infrared human sensor measures body heat

Omron Electronic Components has introduced a non-contact MEMS thermal sensor that it claims can detect the presence of humans in an area without the need for movement. 

The sensor is intended as an alternative to pyroelectric sensors or PIR detectors in home automation, building automation, healthcare, security and industrial applications.

Typically human presence sensors rely on movement, but the Omron device, the D6T is designed to detect occupation by sensing body heat.

When used for switching off lighting in an office, conventional sensors often fail to distinguish between an unoccupied space and a stationary person.  

As D6T sensors are able to monitor the temperature of a room, they can also be used to control the level of heating and air conditioning systems and maintain optimal room temperature levels without wasting energy. 

Unusual changes in temperature can also be used in other ways, for example to detect line stoppages, identify hot spots before a fire breaks out or in clinical applications to check whether a patient has left the bed. 

The technology behind Omron’s D6T thermal sensors combines a MEMS micro-mirror structure for efficient IR radiation detection with a high-performance silicon lens to focus the infrared rays onto its thermopiles. 

The devices have a ±1.5 deg C accuracy with noise immunity (measured as noise equivalent temperature difference) of 140mK.