# US 10,871,613 B2 · Optical waveguide apparatus and display > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,871,613 B2 - Document ID: US10871613B2 - Status: Granted - Kind: B2 - Application number: 16/358,656 - Filed: 2019-03-19 - Published: 2019-10-03 - Granted: 2020-12-22 - Earliest claimed: 2018-03-30 - Assignees: Coretronic Corporation - Applicants: Coretronic Corporation - Inventors: Meng-Hsuan Lin; Chih-Wei Shih; Chuan-Te Cheng - Web page: https://patentgrep.com/patent/US10871613B2 ## CPC - G02B 6/122: Basic optical elements, e.g. light-guiding paths - G02B 6/00: Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings - G02B 6/0016: {Grooves, prisms, gratings, scattering particles or rough surfaces} - G02B 6/0031: {Reflecting element, sheet or layer} - G02B 6/34: utilising prism or grating {(G02B6/293 takes precedence)} - G02B 27/0101: {characterised by optical features (G02B27/0172 takes precedence)} - G02B 27/0172: {characterised by optical features} - G03B 21/2066: {Reflectors in illumination beam (in projection beam G03B21/28)} - G02B 2027/0112: {comprising device for genereting colour display} - G02B 2027/0118: {comprising devices for improving the contrast of the display / brillance control visibility} - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS - G03B: APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR (optical parts of such apparatus G02B; photosensitive materials or processes for photographic purposes G03C; apparatus for processing exposed photographic materials G03D) ## Abstract An optical waveguide apparatus including an optical waveguide element and an optical recycling element is provided. The optical waveguide element includes a first surface and a second surface opposite to the first surface. The first surface or the second surface includes an optical structure. An incident light enters the optical waveguide element via the first surface and is transmitted to the second surface. The optical recycling element is disposed on the second surface of the optical waveguide element. The incident light is transmitted to the optical recycling element via the second surface. The optical recycling element changes a transmission direction of the incident light to generate a recycled light. The recycled light enters the optical waveguide element via the second surface and is transmitted to the first surface. ## Claims ### Claim 1 An optical waveguide apparatus comprising: an optical waveguide element comprising: a first surface; and a second surface opposite to the first surface, wherein an optical structure formed on the first surface or the second surface is a diffractive structure for generating a diffracted light beam, the diffractive structure comprises a light-transmissive microstructure region, and an incident light enters the optical waveguide element via the first surface and is transmitted to the second surface; and an optical recycling element disposed on the second surface of the optical waveguide element, wherein the incident light is transmitted to the optical recycling element via the second surface, the optical recycling element changes a transmission direction of the incident light to generate a recycled light, the recycled light passes through the light-transmissive microstructure region to generate a refractive diffracted light by refractive diffraction, the refractive diffracted light enters the optical waveguide element via the second surface and is transmitted to the first surface, and the incident light and the refractive diffracted light are transmitted in the optical waveguide element, and then the incident light and the refractive diffracted light transmit into a projection target after leaving the optical waveguide element. ### Claim 2 (depends on 1) The optical waveguide apparatus of claim 1, wherein the optical structure is formed on the first surface of the optical waveguide element, the incident light enters the optical waveguide element by refractive diffraction via the first surface, and the refractive diffracted light is transmitted to the first surface via the second surface and undergoes reflective diffraction at the optical structure to be transmitted in the optical waveguide element. ### Claim 3 (depends on 1) The optical waveguide apparatus of claim 1, wherein the optical structure is formed on the second surface of the optical waveguide element, the incident light is transmitted to the second surface via the first surface and undergoes reflective diffraction at the optical structure to be transmitted in the optical waveguide element. ### Claim 4 (depends on 1) The optical waveguide apparatus of claim 1, wherein the optical recycling element is selected from one of a reflection mirror, a band pass filter, a dichroic mirror, a diffraction element, and a planar optical element. ### Claim 5 (depends on 1) The optical waveguide apparatus of claim 1, wherein the optical recycling element comprises an optical film layer, and the optical film layer is disposed on a surface of the optical structure. ### Claim 6 (depends on 1) The optical waveguide apparatus of claim 1, wherein the optical waveguide element comprises one single waveguide plate, and the first surface and the second surface are two opposite surfaces of the one single waveguide plate. ### Claim 7 (depends on 1) The optical waveguide apparatus of claim 1, wherein the optical waveguide element comprises a first waveguide plate and a second waveguide plate, wherein the first waveguide plate and the second waveguide plate each comprises the optical structure, the first waveguide plate and the second waveguide plate are arranged in parallel along a light transmission direction, the first surface is a surface where the first waveguide plate receives the incident light, and the second surface is a surface where the second waveguide plate faces the optical recycling element. ### Claim 8 (depends on 1) The optical waveguide apparatus of claim 1, wherein the optical waveguide element comprises a first waveguide plate, a second waveguide plate, and a third waveguide plate, wherein the first waveguide plate, the second waveguide plate, and the third waveguide plate each comprises the optical structure, the first waveguide plate, the second waveguide plate, and the third waveguide plate are arranged in parallel along a light transmission direction, the first surface is a surface where the first waveguide plate receives the incident light, and the second surface is a surface where the third waveguide plate faces the optical recycling element. ### Claim 9 (depends on 8) The optical waveguide apparatus of claim 8, wherein the incident light comprises a first color light, a second color light, and a third color light, wherein the first color light is transmitted in the first waveguide plate, the second color light is transmitted in the second waveguide plate, and the third color light is transmitted in the third waveguide plate. ### Claim 10 (depends on 8) The optical waveguide apparatus of claim 8, wherein the optical recycling element is further disposed between the first waveguide plate and the second waveguide plate and between the second waveguide plate and the third waveguide plate. ### Claim 11 (depends on 1) The optical waveguide apparatus of claim 1, further comprising a protective element disposed on a side of the second surface of the optical waveguide element, wherein the optical recycling element is disposed between the optical waveguide element and the protective element. ### Claim 12 (depends on 1) The optical waveguide apparatus of claim 1, wherein the first surface comprises the optical structure, the incident light enters the optical waveguide element via the first surface and is transmitted to the second surface, and the optical recycling element is integrally formed on the second surface of the optical waveguide element, wherein the optical recycling element is a diffraction element. ### Claim 13 (depends on 1) The optical waveguide apparatus of claim 1, wherein the optical waveguide element comprises another optical structure, and the incident light and the refractive diffracted light are transmitted to a projection target via the another optical structure. ### Claim 14 A display for projecting an image light beam to a projection target, the display comprising: a projection apparatus, adapted to project an incident light, wherein the incident light is the image light beam; and an optical waveguide apparatus comprising: an optical waveguide element, comprising: a first surface; and a second surface opposite to the first surface, wherein an optical structure formed on the first surface or the second surface is a diffractive structure for generating a diffracted light beam, and the incident light enters the optical waveguide element via the first surface and is transmitted to the second surface; and an optical recycling element, disposed on the second surface of the optical waveguide element, wherein the incident light is transmitted to the optical recycling element via the second surface, the optical recycling element changes a transmission direction of the incident light to generate a recycled light, the recycled light passes through the diffractive structure to generate a refractive diffracted light by refractive diffraction, the refractive diffracted light enters the optical waveguide element via the second surface and is transmitted to the first surface, and the incident light and the refractive diffracted light are transmitted in the optical waveguide element, and then the incident light and the refractive diffracted light transmit into the projection target after leaving the optical waveguide element.