Patent ID: 7556198

Claim:
A detection and decoding unit for a bar code scanner, comprising: an interface for receiving a scan signal generated by detection of a reflected scan signal generated by reflection of a scan beam emitted from a scan window of the scanner and directed back into the scanner through the scan window; and a processor operative to process the scan signal received by the interface, the processor being operative to receive information relating to the signal strength of the scan signal and information relating to levels of noise affecting the scan signal and to compute a plurality of signal to noise ratios for the scan signal, the processor being operative to process the scan signal to generate a plurality of candidate decoding results representing one or more bar code data resulting from an attempt to decode a bar code, to associate the signal to noise ratios with the decoding results, to perform a comparative evaluation of the candidate decoding results including a comparison of the signal to noise ratios, and to choose one of the candidate decoding results based upon the comparative evaluation.