Infrared (IR) Sensors

infrared sensor for human detectionST’s Infrared sensors (IR sensors) have been designed to accurately detect object movements and sense human presence by measuring the IR radiation of objects within their field of view.

There are several different technologies to support IR-based sensors, and ST offers the TMOS IR sensor solution to detect human or object presence and movement detection with high accuracy and low-power consumption, directly with a digital interface.

TMOS IR sensor applications

ST’s TMOS IR sensors enable various use cases detecting human or object presence/absence and movement around us.

smart home and building
Home Automation
  • Smart home/building
  • Presence/Motion Detection
energy-saving smart lightening
SMART Lighting
  • Presence/Motion Detection
  • Energy saving
smart IoT air conditioner
SMART IoT Home Appliance
  • Presence/Motion Detection
  • Energy saving
security alarm system for presence detection
Security Alarm System
  • Presence/Motion Detection
  • Energy saving


What is a TMOS IR sensor and how it works

TMOS stands for Thermal MOS. The sensor is fabricated with the unique technology of the CMOS-SOI process. The TMOS works by integrating the IR radiation emitted by objects in its field of view (FoV). This radiation reaches its MEMS-thermally-insulated gate, realized with the ST state-of-the-art MEMS technology.


Infrared sensor types

ST’s Infrared sensing technology is based on a thermally isolated MOS transistor array: IR radiation incident on gates can bias the MOS transistors which can be used to remotely sense temperature of objects or people. This innovative technology offers many advantages to system designers since it shows much greater sensitivity with respect to known and competitive technologies like PIR and capability to sense non-moving targets. These two key benefits enable new applications and permit significant system cost reduction, removing, for example, IR concentrators like Fresnel lenses.


Key benefits of ST’s TMOS IR sensors

  • Presence detection for both stationary and moving objects
  • No need of Fresnel lens to detect objects less than 4 meters
  • Lower power consumption with embedded SMART algorithm
  • Small package
  • Digital interface