NON VOLATILE ELECTROOPTIC TYPE READ -ONLY MEMORY IN HIGH-DENSITY TWO- DIMENSIONAL SYMBOLIC DISPLAY METHOD

摘要

PURPOSE: To protect security by determining sub sets for respective rows by a specified rule different from the rule specified for the row adjacent to the row and turning the respective rules to the function of the detectable characteristics of respective marks. CONSTITUTION: Different code word sub sets are used in the different rows and the respective sub sets satisfy an identifier function standard. An identifier function is used so as to divide the 11400 pieces of mark patterns utilizable by the symbol display method into the three mark patterns respectively composed of the 929 pieces of code words. The identifier function can adopt the various widths of the marks (optically detectable bars and spaces for instance) of ON and OFF of the mark patterns as input and supply the number of 0-8 as output. Thus, the security is protected.