INFORMATION RECORDING MEDIUM, METHOD FOR READING INFORMATION FROM INFORMATION RECORDING MEDIUM, AND IMAGE DETECTING DEVICE

摘要

In an information recording medium (1) wherein diffraction grating cells (10) are arranged, one information recording area (5) is constituted with a plurality of types of diffraction grating cells (10). Among the diffraction grating cells (10) constituting the information recording area (5), at least one type of diffraction grating cell (10) is an information recording element, and among the diffraction grating cells (10) constituting the information recording area (5), other types of diffraction grating cells (10) are information hiding elements and record information by two-dimensional arrangement within the information recording area (5) of the diffraction grating cell (10), i.e., the information recording elements.