US 12,455,472 B2
Optical device
Tomu Takeda, Tochigi (JP); and Hideto Sagawa, Tochigi (JP)
Assigned to DEXERIALS CORPORATION, Shimotsuke (JP)
Appl. No. 18/270,124
Filed by DEXERIALS CORPORATION, Shimotsuke (JP)
PCT Filed Mar. 7, 2022, PCT No. PCT/JP2022/009686
§ 371(c)(1), (2) Date Jun. 28, 2023,
PCT Pub. No. WO2022/196409, PCT Pub. Date Sep. 22, 2022.
Claims priority of application No. 2021-041786 (JP), filed on Mar. 15, 2021.
Prior Publication US 2024/0069378 A1, Feb. 29, 2024
Int. Cl. G02F 1/1335 (2006.01); G02B 5/30 (2006.01)
CPC G02F 1/133548 (2021.01) [G02B 5/3058 (2013.01)] 12 Claims
OG exemplary drawing
 
1. An optical device comprising a light source, an incident-side polarizing element, an optical modulating element, an emission-side first polarizing element, and an emission-side second polarizing element, wherein
the emission-side first polarizing element has a wire-grid structure and comprises a plurality of convex portions arranged on one side of a transparent substrate and spaced apart from each other at a pitch shorter than the wavelength of light in the used band of the light source, the convex portions are lattice-shaped convex portions extending in a predetermined direction, and the lattice-shaped convex portions comprise, in order from the transparent substrate side, a base-shaped portion with a width in a cross-section orthogonal to the predetermined direction becomes narrower toward the tip and a protruding portion protruding from the base-shaped portion and having absorption properties for the wavelength of light in the used band,
the emission-side second polarizing element has a wire-grid structure and comprises a plurality of convex portions arranged on one side of the transparent substrate and spaced apart from each other at a pitch shorter than the wavelength of light in the used band of the light source, and the convex portions are lattice-shaped convex portions extending in a predetermined direction, and the lattice-shaped convex portions comprises, in order from the transparent substrate side, a reflection layer, a dielectric layer, and an absorption layer,
the rotation angle of the orthogonal axis of the emission-side first polarizing element relative to the orthogonal axis of the incident-side polarizing element is within ±8.5°, and
the rotation angle of the orthogonal axis of the emission-side second polarizing element relative to the orthogonal axis of the incident-side polarizing element is within ±0.7°.