Virtual keyboard: A human-computer interaction device based on laser and image processing

Keyboard is a major kind of input device for computer and intelligent device, especially those portable equipment. Aiming at more intelligent human-computer interaction, a virtual keyboard system is presented on the basis of laser and image processing. The virtual keyboard consists of infrared laser module, keyboard pattern projector, embedded system and a single image sensor. The keyboard pattern can be implemented through the projector. A CMOS image sensor is used to collect the sequential frames of fingertips keystroke. Every keystroke can be detected accurately by image processing including morphology principle and ellipse fitting. Experiment results show that the virtual keyboard system can work reliably with high-speed response and high accuracy.