The IR marker is an infrared LED emitter.
The marker emission wavelength is 850 nm.
The combination of markers forms a Reference Bar — an elementary optical pattern. Unique combinations of patterns (or individual markers) shape the Feature. The presence and location of features in the tracking area is determined by Host based on the data received from an Alt.

Using active markers

The use of active (light-emitting) markers is determined by the inside-out tracking method. This approach allows to multiply the size of the tracking zone by regulating the emitting power of the markers. Meanwhile, the power consumption of the tracker is unchanged.
The marker can operate over a wide range of power supply voltages.

IR environment

In standard IR environments all markers have identical properties, frequency and wavelength. They are constantly emitting light in the IR range and illuminated by a green LED indication. Markers don't have any specific IDs.
The user have opportunity to use custom markers and IR environment (e.g. for customizing a tracking area). See more in Environment.