Patent ID: 7740176

Claim:
A hand held bar code reading apparatus for reading a bar code on a substrate, the apparatus comprising: a microprocessor addressable image frame memory being configured to simultaneously retain pixel values making up a frame of image data, the frame of image data including a plurality of pixel values which together represent a one dimensional slice of said substrate or a two dimensional area of said substrate; an image sensing and processing circuit for outputting image data, the image sensing and processing circuit including an image sensor array having a plurality of pixels and at least one image data output interface, the image sensing and processing circuit being configured to read out image signals from said image sensor array and to digitize such signals, the image sensing and processing circuit processing image data and further being configured to output image data through said image data output interface for capture into said image frame memory; a microprocessor integrated circuit being configured to address image data of said image frame memory for processing of image data subsequent to capture of image data in said microprocessor addressable image frame memory, the apparatus being configured so that prior to receiving a trigger signal, said apparatus serially and continuously captures into said image frame memory a plurality of frames of image data; wherein said apparatus is configured to wait for a trigger signal, and wherein said apparatus is further configured so that when receiving said trigger signal said apparatus addresses for processing pixel values of a certain frame of image data retained in said memory, the certain frame of image data addressed for processing having a capture initiation time prior to a time that said trigger signal is received.