OPTICAL STRUCTURE BODY FOR AUTHENTICATION, RECORDING MEDIUM FOR AUTHENTICATION, AND CONFIRMATION METHOD

摘要

An optical structure body (3) having a plurality of minute optical unit areas (4) is provided on a substrate (2). Each of the minute optical unit areas (4) has a plurality of types of minute divisions (A, B) recorded with a depth which is phase information on a Fourier transform image of the original image made into a multinary value. Alternatively, each pair of adjacent minute optical unit areas (4) has a plurality of types of minute divisions (A, B) recorded with a depth which is a Fourier transform image of the original image made into a multinary value.