Heat vision cameras or thermal imaging cameras are in fact really heat detecting sensors.
These thermal cameras are also known by various names including;
Heat Vision Camera
Thermal Vision Camera
Thermal Imaging Sensor
Thermal Imaging Camera
Temperature Sensor Camera
Thermal Heat Vision Sensor
Heat Signature Camera
Heat Sensor Camera
Thermal vision cameras make pictures or video from heat, not visible light.
Heat (infrared thermal radiation) and light are both parts of the electromagnetic spectrum.
However, a camera, which can detect visible light will not see thermal radiation and vice versa.
Thermal cameras detect more than just heat.
Heat vision cameras detect the tiny differences in heat, even as small as 0.01° Celsius.
This information is then displayed as various colors on a display, in thermal software or apps.