A virtual data input device to optically interface with an operator to
detect the position of objects within an input zone, i.e., an area
defined as a "virtual keyboard" in which the operator may interact to
enter character or other data into computing equipment. The input device
includes a source of optical sensor light illuminating the input zone
that reflects off the objects in a direction generally toward the input
device. The device also includes an optical detector arranged to receive
reflected sensor light as a light pattern, representing the position of
the objects within the input zone, and converts the reflected light
pattern to an electrical signal. A microprocessor then receives the
electrical signal and correlates the electrical signal to character or
other data. An image generator may be used to project an optical image
that represents, for example, an image of a keyboard.