# US 2019/0171019 A1 · Image Display Optical Apparatus and Image Generation Method Thereof > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0171019 A1 - Document ID: US20190171019A1 - Status: Published application - Kind: A1 - Application number: 16/205,366 - Filed: 2018-11-30 - Published: 2019-06-06 - Earliest claimed: 2017-12-01 - Inventors: Tae Kyung Kim; Hyung Won Seo - Web page: https://patentgrep.com/patent/US20190171019A1 ## CPC - G02B 27/0172: {characterised by optical features} - G02B 6/0016: {Grooves, prisms, gratings, scattering particles or rough surfaces} - G02B 6/005: {provided by one optical element, or plurality thereof, placed on the light output side of the light guide} - G02B 2027/0127: {comprising devices increasing the depth of field} - G02B 2027/0132: {comprising binocular systems} - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS ## Abstract An image display optical apparatus and an image generating method thereof are disclosed. The image display optical apparatus includes a substrate arranged as at least one layer, at least one first diffractive element located on one side of the substrate and which receives a beam, and a plurality of second diffractive elements arranged at predetermined intervals on the substrate and which output beams diffracted by the at least one first diffractive element and guided through the substrate. ## Claims ### Claim 1 An optical apparatus comprising: a substrate arranged as at least one layer; at least one first diffractive element located on one side of the substrate and which receives a beam; and a plurality of second diffractive elements arranged at predetermined intervals on the substrate, wherein the plurality of second diffractive elements output beams diffracted by the at least one first diffractive element and guided through the substrate. ### Claim 2 (depends on 1) The optical apparatus of claim 1, wherein the substrate is arranged as at least three layers. ### Claim 3 (depends on 2) The optical apparatus of claim 2, wherein an interval between the second diffractive elements located on a same layer of the substrate corresponds to a diameter of a pupil, and wherein an interval between the second diffractive elements located on different layers of the substrate is an interval obtained by dividing the diameter of the pupil. ### Claim 4 (depends on 1) The optical apparatus of claim 1, wherein a size of the at least one first diffractive element of each layer of the substrate is equal to or greater than a maximum step length of a beam guided through the substrate or is equal to or less than a size of a beam incident to the at least one first diffractive element. ### Claim 5 (depends on 1) The optical apparatus of claim 1, wherein diffraction ratios of all or a portion of the second diffractive elements located on a same layer of the substrate are different from each other. ### Claim 6 (depends on 1) The optical apparatus of claim 1, wherein the at least one first diffractive element located on each layer of the substrate is used for wavelength-multiplexing of red light, green light, and blue light included in an incident beam or includes a laminated structure of sub-diffractive elements that output red light, green light, and blue light, and the second diffractive elements located on each layer of the substrate include a first sub-diffractive element, a second sub-diffractive element, and a third sub-diffractive element that respectively output red light, green light, and blue light that are guided through each layer of the substrate, and wherein sub-diffractive elements of an identical type located on each layer of the substrate are arranged at predetermined intervals, and sub-diffractive elements of the identical type located on different layers of the substrate are arranged without overlapping each other. ### Claim 7 (depends on 6) The optical apparatus of claim 6, wherein the second diffractive elements located on each layer of the substrate include a fourth sub-diffractive element, a fifth sub-diffractive element, and a sixth sub-diffractive element that respectively output red light, green light, and blue light that are guided through each layer of the substrate; the first sub-diffractive element, the second sub-diffractive element, and the third sub-diffractive element and the fourth sub-diffractive element, the fifth sub-diffractive element, and the sixth sub-diffractive element are arranged alternately; and all or a portion of a first diffraction range of the first sub-diffractive element, the second sub-diffractive element, and the third sub-diffractive element is different from a second diffraction range of the fourth sub-diffractive element, the fifth sub-diffractive element, and the sixth sub-diffractive element. ### Claim 8 (depends on 7) The optical apparatus of claim 7, wherein the at least one first diffractive element located on each layer of the substrate includes a seventh sub-diffractive element having the first diffraction range and an eighth sub-diffractive element having the second diffraction range. ### Claim 9 (depends on 1) The optical apparatus of claim 1, further comprising: a plurality of third diffractive elements arranged at predetermined intervals on each layer of the substrate, further diffracting a beam diffracted and guided by the least one first diffractive element, and transmitting the beam to the second diffractive elements. ### Claim 10 (depends on 9) The optical apparatus of claim 9, wherein all or some of the plurality of third diffractive elements arranged on a same layer of the substrate have different diffraction ratios. ### Claim 11 (depends on 9) The optical apparatus of claim 9, wherein all or some of the plurality of third diffractive elements of each layer of the substrate are inclined by a predetermined angle based on a waveguide direction from the third diffractive elements to the second diffractive elements. ### Claim 12 (depends on 1) The optical apparatus of claim 1, further comprising: an image generator which generates a plurality of shift images whose total number corresponds to the number of layers of the at least one layer of the substrate and inputs the plurality of shift images as collimated beams to the at least one first diffractive element of each layer of the substrate. ### Claim 13 (depends on 12) The optical apparatus of claim 12, wherein the image generator sequentially outputs the plurality of shift images, and the optical apparatus further comprises: a blocking unit that is located in front of the at least one first diffractive element of each layer of the substrate and transmits or blocks a shift image in synchronization with an output sequence of the shift images of the image generator. ### Claim 14 (depends on 12) The optical apparatus of claim 12, wherein the image generator generates the shift images to be input to the at least one first diffractive element of each layer of the substrate on the basis of an output position of a beam let output from the second diffractive elements of each layer of the substrate and depth information of a corresponding pixel, based on the center of a pupil. ### Claim 15 (depends on 1) The optical apparatus of claim 1, further comprising: a light quantity controller which adjusts a quantity of light incident on a pupil such that the pupil is maintained at a constant size. ### Claim 16 A method of generating an image for an optical apparatus including at least one first diffractive element which receives beams and a plurality of second diffractive elements arranged at predetermined intervals and which output the beams, wherein the at least one first diffractive element and the plurality of second diffractive elements are located on a substrate arranged as one or more layers, the method comprising: determining a position of a pupil; determining an output position of a beamlet that outputs a pixel and is output to the pupil by using a beam let output position function defined by input values of an angle at which the pixel is incident to a first diffractive element, a distance between the substrate and the pupil, and a parameter of each diffractive element; determining an output angle of the beamlet based on depth information of the pixel and the output position of the beam let; determining a shifting amount of each pixel based on a ratio of the output angle to an angle formed by a size of one pixel; and performing, for each layer of the substrate, a process of generating a shift image by shifting each pixel of an original image according to the shifting amount.