User input method and apparatus for handheld computers

摘要

A system and method for providing input to a handheld computing device by provisioning the handheld computing device with a projecting device a projecting device for displaying a graphical representation of a keyboard, the graphical representation including key locations capable of being selected by an object, the graphical image displayed in an area proximate the device; a signal detection system for detecting the presence of an object located at a selected key location within the area; and, a mechanism for determining the selected key in response to detecting an object at a corresponding selected key location and registering the selected key as a keystroke in the computing device.