Range detection and motion capture

Range detection and motion capture sensing hardware.

Embodiments herein disclose a range detection system that includes a line-of-sight (LOS) emitter that outputs a LOS signal (e.g., visible light, infrared, etc.) which is detected at a receiver (e.g., a photodiode). The receiver outputs a signal representing the intensity of the LOS signal at the receiver. The output signal is converted into a digital signal which is then used to identify a distance value corresponding to the intensity of the LOS signal. For example, the range detection system may include a data structure that maps a plurality of digital signals to respective distance values. In this manner, the intensity of the LOS signal measured at the receiver can be correlated to a distance between the emitter and the receiver.

BACKGROUND(1) Field of the Invention(2) The embodiments herein are generally directed to using light-of-sight signals to perform range detection.(3) Description of the Related Art(4) Generally, range detection systems identify the distance between two objects. Range detection may be used in many different systems such radar, motion trackers, video game development, and the like. By determining the distance between objects, systems can perform more complex calculations such as triangulation to determine a 3D location of an object or track an object in free space. However, typical range detection systems are costly and bulky. For example, radar systems require large arrays and expensive computing systems that can perform complex calculations. Thus, in low cost scenarios, the cost and weight of many range detection systems may make these systems impractical.SUMMARY(5) One embodiment described herein is a method that includes receiving, at a line-of-sight (LOS) receiver, a LOS signal outputted by a separate LOS emitter and generating a value representing an intensity of the received LOS signal. The method includes processing the value using a predefined relationship to determine a separation distance between the LOS receiver and the LOS emitter, where the predefined relationship is derived using a known output intensity of the LOS emitter when generating the LOS signal.(6) Another embodiment described herein is a system that includes a LOS receiver configured to receive a LOS sig