PURPOSE: To improve read processing efficiency and a correct read rate by sorting input data roughly by a candidate character selecting circuit and selecting a specific number of candidate characters, and then checking the character set and decreasing a rejection rate.

CONSTITUTION: When one character of binary-coded input character data D is supplied to the candidate character selecting circuit 1 by a driving signal (a), a specific number of candidate characters CH1 are selected on the basis of data in a dictionary memory 2 according to similarity in decreasing order and sorted roughly. A character collating circuit 3 collates the candidate character CH1 with character data CS in a character set memory 4. When one character in the CS coincides with the CH1, the candidate CH3 is sent to an answer buffer memory 6 and when plural characters in the CS coincide with it, a candidate CH2 is decided 5 by referring to a dictionary memory 7 for decision to input the result to the answer buffer memory 6; when the decision is possible, the data is rejected. Consequently, the operability and correct read rate are improved.