abstract |
A hand-supportable digital imaging-based bar code symbol reading device comprises: an ir-based object presence and range detection subsystem; a multi-mode area-type image formation and detection subsystem having a field of view (FOV) and narrow-area and wide area image capture modes of operation; a multi-mode LED-based illumination subsystem having narrow-area and wide area illumination modes of operation; an automatic light exposure measurement and illumination control subsystem; an image capturing and buffering subsystem; an image-processing bar code symbol reading subsystem; and a system control subsystem. The LED-based multi-mode illumination subsystem produces three different fields of LED-based illumination in automatic response to the detection of different conditions within the FOV, by the automatic object presence and range detection subsystem. |