Abstract: Achieved are both high speed in decoding a simple code and stability of decoding of a difficult code. A code image, generated by high-speed imaging control (first imaging control) for causing an imaging unit to generate the code image while causing an illumination unit to execute one type (N1=1) of illumination mode (a polarized illumination mode) among four types of illumination, is decoded by a core (high-speed decoding). On the other hand, a code image, generated by difficult-to-read imaging control (second imaging control) for causing the imaging unit to generate the code image while causing the illumination unit to execute all the four types (N2=4) of illumination modes among the four types of illumination modes, is decoded by a core (difficult-to-read decoding).

Abstract: The present invention provides a portable optical reader, an optical reading method using the portable optical reader and a computer program capable of detecting a high possibility of a reading error and notifying a user of a possibility of a reading error. A character string as a reading target is imaged and a character string is recognized based on the captured image. A plurality of reading formats defining an attribute of the character string is stored, and a first reading format matched with the recognized character string among a plurality of stored reading format is searched. Among the plurality of stored reading formats, a second reading format in which a character string matched with the first reading format as a partial character string is searched. Based on the search result, a possibility of a reading error regarding the recognized character string is notified.

Abstract: The present invention provides a portable optical reader, an optical reading method using the portable optical reader and a computer program capable of detecting a high possibility of a reading error and notifying a user of a possibility of a reading error. A character string as a reading target is imaged and a character string is recognized based on the captured image. A plurality of reading formats defining an attribute of the character string is stored, and a first reading format matched with the recognized character string among a plurality of stored reading format is searched. Among the plurality of stored reading formats, a second reading format in which a character string matched with the first reading format as a partial character string is searched. Based on the search result, a possibility of a reading error regarding the recognized character string is notified.