US 12,066,707 B2
Optical element and image display apparatus
Katsumi Sasata, Minamiashigara (JP); Fumitake Mitobe, Minamiashigara (JP); Hiroshi Sato, Minamiashigara (JP); and Yukito Saitoh, Minamiashigara (JP)
Assigned to FUJIFILM Corporation, Tokyo (JP)
Filed by FUJIFILM Corporation, Tokyo (JP)
Filed on Sep. 30, 2022, as Appl. No. 17/937,370.
Application 17/937,370 is a continuation of application No. PCT/JP2021/014150, filed on Apr. 1, 2021.
Claims priority of application No. 2020-067690 (JP), filed on Apr. 3, 2020; and application No. 2020-079512 (JP), filed on Apr. 28, 2020.
Prior Publication US 2023/0043783 A1, Feb. 9, 2023
Int. Cl. G02F 1/1335 (2006.01); G02B 27/01 (2006.01)
CPC G02F 1/133504 (2013.01) [G02F 1/133524 (2013.01); G02F 1/133541 (2021.01); G02F 1/133543 (2021.01); G02B 27/0172 (2013.01)] 20 Claims
OG exemplary drawing
 
1. An optical element comprising:
a light guide plate;
an incidence portion that causes light to be incident into the light guide plate; and
an emission portion that emits light from the light guide plate,
wherein the incidence portion includes a plurality of incidence diffraction portions, the incidence diffraction portion includes one or more incidence diffraction elements, the emission portion includes a plurality of emission diffraction portions, and the emission diffraction portion includes one or more emission diffraction elements,
each of the incidence diffraction element and the emission diffraction element includes a liquid crystal diffraction layer that is formed of a composition including a liquid crystal compounds,
the liquid crystal diffraction layer has a liquid crystal alignment pattern in which a direction of an optical axis derived from one of the liquid crystal compounds changes while continuously rotating in one in-plane direction, the liquid crystal alignment pattern including a plurality of arrangement axes each including a plurality of the liquid crystal compounds, the plurality of arrangement axes being parallel, and
in the liquid crystal alignment pattern, in a case where the one in-plane direction in which the optical axis derived from the one of the liquid crystal compounds changes while continuously rotating in is set as an in-plane rotation direction and a length over which the direction of the optical axis derived from the one of the liquid crystal compounds rotates by 180° in the in-plane rotation direction is set as an in-plane period,
the in-plane rotation directions of the liquid crystal diffraction layers in at least two of a plurality of the incidence diffraction elements are different from each other.