Method of reading bar code

A method of a reading bar code, comprising the steps of:

• obtaining first bar code data;
• obtaining first information regarding said first bar code data;
• obtaining second bar code data different from said first bar code data;
• obtaining second information regarding said second bar code data;
• making a comparison of said first information and said second information;
• and
• accepting said bar code data as valid data when the comparison result satisfies a predetermined condition.

A method of reading a bar code of stripes and spaces, based on data obtained by scanning the bar code with a scanning beam, in a scanning pattern including the bar code and a pattern surrounding the bar code, comprising:

• obtaining first bar code data of actual bar code data corresponding to scanning stripes and spaces and effective bar code data corresponding to scanning a pattern surrounding the bar code, and deriving first information from the effective bar code data;
• obtaining second bar code data of actual bar code data corresponding to scanning stripes and spaces and effective bar code data corresponding to scanning a pattern surrounding the bar code and deriving second information from the effective bar code data;
• comparing the first information with the second information;
• and
• accepting the bar code data as valid data when the comparison result satisfies a predetermined condition.

A bar code reader system, comprising:

• a reader scanning a bar code and obtaining first bar code data and second bar code data in first and second scans, respectively, of the bar code;
• a processor obtaining first information regarding said first bar code data and second information regarding said second bar code data;
• a comparator comparing said first information and said second information and producing an output accepting said bar code data as valid data when the comparison result satisfies a predetermined condition;
• a detector detecting whether said bar code is out of a detection range;
• and
• the processor rejecting said first bar code data as invalid data when said bar code is out of said detecting range after said first bar code data is obtained.

A bar code reader system, comprising:

• a reader reading a bar code of stripes and spaces by scanning the bar code with a scanning beam, in a scanning pattern including the bar code and a pattern surrounding the bar code, and producing bar code data of actual bar code data corresponding to scanning stripes and spaces and effective bar code data corresponding to scanning the pattern surrounding the bar code;
• a controller controlling the reader to scan the bar code in the scanning pattern in first and second scans to produce fist and second bar code data, respectively;
• a processor processing the first and second bar code data to derive first and second information from the first and second effective bar code data, respectively;
• and
• a comparator comparing the fist information with the second information and producing a comparison result;
• and
• the processor accepting the bar code data as valid data when the comparison result satisfies a predetermined condition.