Hand-held optical scanner for reading two-dimensional bar code symbols

Abstract

A lightweight, easy to grasp and manipulate hand-held optical scanning device for scanning and digitizing image data from a two-dimensional bar code symbol for subsequent decoding in a personal computer platform. The scanning device achieves a small footprint in the user's workspace by utilizing a non-folded, substantially vertical optical path extending from an image viewing area upwardly to a linear charge-coupled device (CCD) array upon which the successive rows of the target two-dimensional bar code symbol are imaged. The scanning device is easily aligned with the symbol by placing it behind the symbol, and scanning of the successive rows of the symbol is accomplished by swiping or rolling the scanning device towards the user. Mechanical rollers on the underside of the scanning device provide translation information for use in clocking data out of the linear CCD array in order to scan the successive rows of the two-dimensional bar code symbol. The operating environment of the computer allows scanning to be initiated by the user without having to use the keyboard or mouse peripheral. As the two-dimensional bar code symbol is being scanned, digitized image data is automatically and in real time ported to a symbol decoding application running in the background, and decoded data from the decoding application is ported into the application the user is running in the foreground. A trackball and a pair of select buttons are optionally provided on the scanning device for mouse emulation, thereby eliminating the need for a separate mouse peripheral device.