How do phones with thermal cameras work?

How do phones with thermal cameras work?

Phones with thermal cameras work by integrating specialised sensors and technology that can detect and capture thermal radiation, also known as infrared radiation or heat.The core component of a thermal camera in a phone is an infrared sensor or detector. These sensors are designed to detect the infrared radiation emitted by objects and convert it into an electrical signal.
A thermal camera typically has a special lens that allows infrared radiation to pass through while filtering out visible light. This lens focuses the incoming infrared radiation onto the sensor.The sensor array in the thermal camera consists of numerous individual sensor elements that can each detect the temperature at a specific point in the field of view.

Temperature Mapping

The captured thermal data is processed to assign different colors or grayscale values to represent the temperature differences. Colder objects are typically displayed in shades of blue or purple, while warmer objects appear in shades of yellow, orange, or red.

Image Processing

  • Internal Processing Unit: The phone’s internal processing unit processes the data from the thermal sensor.
  • Image Generation: It generates a thermal image from the temperature data.
  • Viewing Thermal Image: Users can view the thermal image on their phone’s screen in real-time.
  • Additional Features: The user interface often provides features such as temperature measurement, color palette selection, and the ability to capture and save thermal images and videos.
  • Temperature Accuracy: To provide accurate temperature measurements, thermal cameras in phones require calibration.


In conclusion, phones with thermal cameras work by integrating specialised infrared sensors and technology to detect and capture thermal radiation, commonly known as heat. These cameras employ a series of components and processes, including infrared sensors, lenses, sensor arrays, temperature mapping, image processing, and user interfaces, to provide real-time thermal imaging capabilities.The captured thermal data is processed and presented to users in a visually interpretable form, often using color palettes to represent temperature variations.