Diffraction sheet and method for manufacturing the same, three-dimensional display device, light beam reproduction device, three-dimensional spatial display system, light beam reproduction method, and program

A method for manufacturing a diffraction sheet, comprising:

• forming a first uncured resin layer on a transparent substrate measuring 10 inches or more in diagonal;
• bringing a first diffraction pattern formed on a first surface of a first plate into contact with the first uncured resin layer, the first diffraction pattern being formed in a rectangular area measuring 10 inches or more in diagonal;
• placing a first mask having a plurality of first apertures formed based on a first array pattern on the first plate;
• irradiating the first mask with light to cure a portion of the first uncured resin layer that overlaps the first apertures;
• forming a second uncured resin layer on a surface of the substrate on which the first uncured resin layer is formed;
• bringing a second diffraction pattern, which is different from the first diffraction pattern, formed on a first surface of a second plate into contact with the second uncured resin layer, the second diffraction pattern being formed in a rectangular area measuring 10 inches or more in diagonal;
• placing a second mask having a plurality of second apertures formed based on a second array pattern different from the first array pattern on the second plate;
• and
• irradiating the second mask with light to cure a portion of the second uncured resin layer that overlaps the second apertures.

A diffraction sheet, comprising:

• a transparent substrate;
• and
• a diffraction layer having a first diffraction pattern formed in a first array pattern on the substrate and a second array pattern formed in a second diffraction pattern different from the first array pattern on a same side of the substrate as the first diffraction pattern,
• wherein the second diffraction pattern is thicker than the first diffraction pattern.

A method for reproducing light beams by a light beam reproduction device configured to reproduce light beams virtually emitted from a stereoscopic image when displaying the stereoscopic image in a reproduction space, the light beam reproduction device including a stereoscopic image display unit that displays the stereoscopic image as at least one of a virtual image and a real image by light beams emitted from element cells contained in an element cell set including the element cells formed two-dimensionally corresponding to a reproduction screen,

• wherein the stereoscopic image display unit displays the stereoscopic image in a region at a depth distance corresponding to a social distance in the reproduction space,
• a size of each of the element cells in the element cell set and a pitch of the element cells arranged two-dimensionally are values determined according to a degree to which the stereoscopic image displayed in the reproduction space is observed by an observer, and
• a signal processing unit divides a set of a plurality of the light beams emitted from a surface of the stereoscopic image according to positions on the reproduction screen, associates each of the divided plurality of the light beams to each of the element cells of the element cell set, and calculates components of one or more light beams to be reproduced for each of the element cells of the element cell set.

A non-transitory computer-readable storage medium storing a program for a computer of a light beam reproduction device, the light beam reproduction device being configured to reproduce light beams virtually emitted from a stereoscopic image when displaying the stereoscopic image in a reproduction space, the light beam reproduction device including a stereoscopic image display unit that displays the stereoscopic image as at least one of a virtual image and a real image by light beams emitted from element cells contained in an element cell set composed of a plurality of the element cells arranged two-dimensionally corresponding to a reproduction screen, the program causing the computer to function as a signal processor that divides a set of a plurality of the light beams emitted from a surface of the stereoscopic image according to positions on the reproduction screen, associates each of the divided plurality of the light beams to each of the element cells of the element cell set, and calculates components of one or more light beams to be reproduced for each of the element cells of the element cell set,

• wherein the stereoscopic image display unit displays the stereoscopic image in a region at a depth distance corresponding to a social distance in the reproduction space, and
• a size of each of the element cells in the element cell set and a pitch of the element cells arranged two-dimensionally are values determined according to a degree to which the stereoscopic image displayed in the reproduction space is observed by an observer.