An infrared (IR) tracker is a system that can keep tabs on an object's location by using an IR light source and units that judge where the object is. To provide the light needed to make an IR tracker work, a beacon sends out a constant stream of IR light. Near the beacon are two receivers — one for the X-axis and one for the Y-axis — that are able to judge where an object is based on the disruption of IR light. One use of an IR tracker is to judge where an object is in relation to the tracker device. Finger movements, especially those used for computer touchscreen monitors, also are captured with this technology.
The beacon of an IR tracker is responsible for sending out IR light. This light is needed, because the tracker cannot find anything without an object disrupting the IR light. Depending on what the tracker is used for, the light may be pushed out in all directions, or it may be concentrated on a certain position. For example, an IR car alarm will push light in all directions, while a touchscreen will just use IR light over the monitor.
While the light is important, other components are needed to judge where the light has been disrupted in the IR tracker. This is where the IR receivers come in. When the light is sent out by the beacon, the receivers monitor the stream. If any disruption is made, the receivers will capture the object’s position based on the X-axis and Y-axis. If depth is required, then a third receiver will be used for a Z-axis, but this is uncommon.
One use for an IR tracker is to figure out where an entire object or body is. For example, if the tracker is part of a car alarm, the tracker will be made to send out a wide stream of light and will be ready to track large objects. This system also is useful for motion tracking, because the tracker will be able to capture a body’s every movement.
Other IR tracker systems are used to capture finger movements, which are typically used with computers. For example, an IR touchscreen will cover the screen with IR light and, if a finger disrupts the light, the touchscreen will capture the motion and respond appropriately. Another use is with IR keyboards; a keyboard is projected onto a flat surface and finger movements are captured and relayed as keystrokes to the computer.