An image display device includes image cells arranged two-dimensionally. Each image cell has a hologram layer. The hologram layer includes a diffraction grating in which a one-dimensional grating pattern extending in a first direction is repeated in a second direction perpendicular to the first direction. Among the plurality of image cells, two or more image cells that are in a row in the second direction and correlated to one color constitute one image cell group. The image cell group includes a section in which the spatial frequency of the diffraction grating is proportionately small as the distance in the second direction from one end of the image cell group increases such that, while a viewpoint is positioned at a predetermined angle relative to an image display device, the two or more image cells constituting the image cell group display the same color as each other.

A display including a relief structure forming layer having a major surface with a relief type diffractive structure that displays a three-dimensional object as a diffraction image; and a reflective layer at least partially covering a region of the major surface where the diffractive structure is provided. A portion of the diffractive structure in a first region includes first and second linear parts forming a first lattice, and first parts arranged in respective gaps of the first lattice. The first and second linear parts each having a solid line shape form a first pattern. A portion of the diffractive structure in a second region includes third and fourth linear parts alternately arranged in the width direction thereof. The third linear parts each having a dashed line shape and the fourth linear parts each having a dashed or dotted line shape form a second pattern.

An optical device is formed by hot stamping a demetallized hologram to an optically variable foil or to a coating of optically variable ink. In another embodiment a hologram is hot stamped to a banknote or document printed with a color-shifting ink.

An identification medium can be affixed to cloth or leather products by sewing. A cholesteric liquid crystal layer on which an embossed surface for forming a hologram is formed, is sandwiched between a first supporting member and a second supporting member. A mounting region that can be affixed to clothing, etc., by sewing, is formed.