# US 2019/0377181 A1 · Optical Systems for Displays > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0377181 A1 - Document ID: US20190377181A1 - Status: Published application - Kind: A1 - Application number: 16/089,006 - Filed: 2017-06-06 - Published: 2019-12-12 - Earliest claimed: 2016-06-21 - Assignees: Apple Inc. - Applicants: Apple Inc. - Inventors: Graham B. Myhre; Eric J. Hansotte; Guolin Peng; Hyungryul Choi; Se Baek Oh; Paul Gelsinger-Austin - Web page: https://patentgrep.com/patent/US20190377181A1 ## CPC - G02B 27/017: {Head mounted} - G02B 27/0172: {characterised by optical features} - G02B 6/0023: {provided by one optical element, or plurality thereof, placed between the light guide and the light source, or around the light source} - G02B 6/0035: {provided on the surface of the light guide or in the bulk of it} - G02B 2027/0123: {comprising devices increasing the field of view} - G02B 2027/0174: {holographic} - G02B 2027/0178: {Eyeglass type (eyeglass details G02C)} - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS ## Abstract An electronic device may include a display system for presenting images close to a user's eyes. The display system may include a display unit that directs light and an optical system that redirects the light from the display unit towards a user's eyes. The optical system may include an input coupler and an output coupler formed on a waveguide. The input coupler may redirect light from the display unit so that it propagates in the waveguide towards the output coupler. The output coupler may redirect the light from the input coupler so that it exits the waveguide towards the user's eyes. A light-redirecting element may be used to redirect edge light that would otherwise be outside of the user's field of view towards the user's eyes. ## Claims ### Claim 1 A display system, comprising: a display unit; an optical system that receives light from the display unit and that redirects the light out of the optical system, wherein the optical system includes an input coupler, an output coupler, and a first waveguide that propagates light along a first direction; and a light-redirecting element interposed between the display unit and the optical system, wherein the light-redirecting element includes a second waveguide that propagates light along a second direction. ### Claim 2 (depends on 1) The display system defined in claim 1 wherein the input coupler and the output coupler each include a holographic optical element. ### Claim 3 (depends on 1) The display system defined in claim 1 wherein the input coupler receives the light from the light-redirecting element and redirects the light towards the output coupler. ### Claim 4 (depends on 3) The display system defined in claim 3 wherein the output coupler receives the light from the input coupler and redirects the light out of the optical system. ### Claim 5 (depends on 1) The display system defined in claim 1 wherein light-redirecting element comprises an additional input coupler and an additional output coupler on the second waveguide. ### Claim 6 (depends on 5) The display system defined in claim 5 wherein the additional input coupler and the additional output coupler each include a holographic optical element. ### Claim 7 (depends on 5) The display system defined in claim 5 wherein the additional input coupler receives the light from the display unit and redirects the light towards the additional output coupler. ### Claim 8 (depends on 7) The display system defined in claim 7 wherein the additional output coupler receives the light from the additional input coupler and redirects the light towards the input coupler. ### Claim 9 (depends on 1) The display system defined in claim 1 wherein the first direction is perpendicular to the second direction. ### Claim 10 A display system, comprising: a display unit; an optical system that receives light from the display unit and that redirects the light out of the optical system, wherein the optical system includes a first input coupler, a first output coupler, and a waveguide; and a light-redirecting element interposed between the input coupler and the output coupler, wherein the light-redirecting element includes a second input coupler and a second output coupler on the waveguide, and wherein the second input coupler receives the light from the first input coupler and the first output coupler receives the light from the second output coupler. ### Claim 11 (depends on 10) The display system defined in claim 10 wherein the first and second input couplers and the first and second output couplers each comprise a holographic optical element. ### Claim 12 (depends on 10) The display system defined in claim 10 wherein the waveguide propagates light from the first input coupler to the second input coupler along a first direction and wherein the waveguide propagates light from the second input coupler to the second output coupler along a second direction. ### Claim 13 (depends on 12) The display system defined in claim 12 wherein the first direction is perpendicular to the second direction. ### Claim 14 (depends on 10) The display system defined in claim 10 wherein the first input coupler has smaller dimensions than the first output coupler. ### Claim 15 A display system, comprising: a display unit; and an optical system that receives light from the display unit and that redirects the light out of the optical system, wherein the optical system includes an input coupler, an output coupler, and a waveguide that propagates light from the input coupler to the output coupler, and wherein the output coupler includes first and second non-parallel interference patterns. ### Claim 16 (depends on 15) The display system defined in claim 15 wherein a thickness of the input and output couplers is greater than a thickness of the waveguide. ### Claim 17 (depends on 15) The display system defined in claim 15 wherein the input and output couplers each comprises holographic optical elements. ### Claim 18 (depends on 17) The display system defined in claim 17 wherein the holographic optical elements are color multiplexed. ### Claim 19 (depends on 15) The display system defined in claim 15 wherein the first and second interference patterns each have a modulated diffraction efficiency. ### Claim 20 (depends on 15) The display system defined in claim 15 wherein the second interference pattern is located in an upper portion of the output coupler and a lower portion of the output coupler.