# US 2019/0318706 A1 · Display device with dynamic resolution enhancement > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0318706 A1 - Document ID: US20190318706A1 - Status: Published application - Kind: A1 - Application number: 16/027,035 - Filed: 2018-07-03 - Published: 2019-10-17 - Earliest claimed: 2018-04-16 - Assignees: Oculus VR, LLC - Applicants: Oculus VR, LLC - Inventors: Fenglin Peng; Lu Lu; Jasmine Soria Sears; Ying Geng; Wai Sze Tiffany Lam - Web page: https://patentgrep.com/patent/US20190318706A1 ## CPC - G09G 3/007: {Use of pixel shift techniques, e.g. by mechanical shift of the physical pixels or by optical shift of the perceived pixels} - G09G 5/10: Intensity circuits - G02B 5/30: Polarising elements (light-modulating devices with active elements G02F1/00) - G02B 26/08: for controlling the direction of light (in light guides G02B6/35) - G02B 27/017: {Head mounted} - G02B 2027/0138: {comprising image capture systems, e.g. camera} - G02B 2027/014: {comprising information/image processing systems} - G09G 2300/0439: Pixel structures - G09G 2330/08: Fault-tolerant or redundant circuits, or circuits in which repair of defects is prepared - G09G 2330/10: Dealing with defective pixels - G09G 2340/04: Changes in size, position or resolution of an image - G09G 2340/0407: Resolution change, inclusive of the use of different resolutions for different screen areas - G09G 2340/0435: Change or adaptation of the frame rate of the video stream - G09G 2340/0457: Improvement of perceived resolution by subpixel rendering - G09G: ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION (arrangements for transferring data between digital computers and displays G06F3/14; static indicating arrangements comprising an association of a number of separate sources or light control cells G09F9/00; static indicating arrangements comprising integral associations of a number of light sources H01J, H01K, H10H, H05B33/12; scanning, transmission or reproduction of documents or the like, e.g. facsimile transmission, details thereof H04N1/00) - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS ## Abstract A display apparatus includes an electronic display having a pixel array configured to display a sequence of subframes, and an image shifting electro-optic device that is operable to shift at least a portion of an image of the display pixel array synchronously with displaying the sequence of subframes, so as to form a sequence of offset subframe images for providing an enhanced image resolution and pixel correction in a compound image. The image shifting electro-optic device may include a polarization switch in series with a polarization grating, for shifting image pixels between offset image positions in coordination with displaying consecutive subframes. ## Claims ### Claim 1 A display apparatus comprising: an electronic display comprising a pixel array configured to display a sequence of subframes; and, an optics block for forming an image of the pixel array, the image comprising an array of image pixels disposed at an image pixel pitch; wherein the optics block comprises an image shifting electro-optic device (ISOED) operable to shift at least a portion of the image synchronously with displaying the sequence of subframes, so as to form a sequence of offset subframe images for providing an enhanced effective image resolution in a compound image composed of the offset subframe images. ### Claim 2 (depends on 1) The display apparatus of claim 1 wherein the ISOED is configured to shift the image by one or more image shifts, further comprising a display processor configured to obtain the sequence of subframes from an input image frame accounting for the one or more image shifts. ### Claim 3 (depends on 1) The display apparatus of claim 1 wherein the ISOED is configured to move the image by a fraction of the pixel pitch so as to increase image pixel density of the compound image. ### Claim 4 (depends on 2) The display apparatus of claim 2, wherein the input image frame is defined at a higher resolution than the pixel array of the electronic display, and wherein the display processor is configured to sub-sample the input image frame, or image data related thereto, with one or more sampling offsets matching the one or more image shifts to obtain the sequence of subframes. ### Claim 5 (depends on 1) The display apparatus of claim 1 further comprising a controller configured to cause the ISOED to shift the image between consecutive subframes from the sequence of subframes. ### Claim 6 (depends on 1) The display apparatus of claim 1 wherein the ISOED is configured to shift the image by the image pixel pitch, or a multiple thereof, so as to move an image pixel into a position of another image pixel prior to the shift for enabling a compensation for defective pixels. ### Claim 7 (depends on 6) The display apparatus of claim 6 further comprising a memory coupled to at least one of the display processor or the controller and configured for saving pixel information related to the defective pixels, and wherein the display processor is configured to generate the subframes based at least in part on the pixel information saved in the memory. ### Claim 8 (depends on 7) The display apparatus of claim 7 wherein the display processor is configured to generate at least one of a greyscale map or a subframe scaling map based at least in part on the pixel information saved in the memory, and to use the at least one of the greyscale map or the subframe scaling map when generating the plurality of subframes. ### Claim 9 (depends on 7) The display apparatus of claim 7 comprising a camera or detector system disposed to receive light emitted by the electronic display and configured to identify defective pixels in the pixel array of the electronic display. ### Claim 10 (depends on 1) The display apparatus of claim 1 wherein the array of pixels of the electronic display is configured to emit image light for displaying the subframes, and wherein: the ISOED comprises a first steering device disposed to receive the image light and configured to switchably impart a first angular shift upon the image light from the electronic display. ### Claim 11 (depends on 10) The display apparatus of claim 10 wherein the image light received by the steering device is polarized, and wherein the first steering device comprises: a first polarization switch configured to switch the image light between two orthogonal polarization states, and a first polarization grating disposed in sequence with the first polarization switch and configured to diffract the image light of the two orthogonal polarization states at two polarization-dependent angles that differ by the first angular shift. ### Claim 12 (depends on 11) The display apparatus of claim 11 comprising a polarization conditioning device configured to transmit the image light towards the first polarization switch in a circular polarization state, and wherein: the first polarization switch comprises a first switchable half-wave plate (HWP), and the first polarization grating comprises at least one of a first Pancharatnam Berry Phase (PBP) grating or a first volume holographic grating. ### Claim 13 (depends on 11) The display apparatus of claim 11 further comprising a second steering device disposed in sequence with the first steering device, the second steering device comprising: a second polarization switch, and a second polarization grating disposed in sequence with the second polarization switch and configured to diffract the image light incident thereon in dependence on the polarization state thereof for imparting a second angular shift upon the image light. ### Claim 14 (depends on 13) The display apparatus of claim 13 wherein the second polarization grating is configured to diffract the image light incident thereon in a different plane than the first polarization grating for imparting a second angular shift upon the image light. ### Claim 15 (depends on 13) The display apparatus of claim 13 comprising a polarization conditioning device disposed upstream of the first and second steering devices and configured to transmit the image light in a circular polarization state, and wherein: at least one of the first polarization switch or the second polarization switch comprises a switchable half-wave plate (HWP), and at least one of the first polarization grating and the second polarization grating comprises at least one of a Pancharatnam Berry Phase (PBP) grating or a holographic volume grating. ### Claim 16 A method for operating an electronic display comprising: displaying, with a pixel array of the electronic display, a sequence of subframes for forming an image; and; shifting at least a portion of the image by one or more images shifts synchronously with displaying the sequence of subframes so as to provide at least one of: an enhanced effective image resolution, or a compensation for defective pixels. ### Claim 17 (depends on 16) The method of claim 16 further comprising sub-sampling a higher-resolution input image frame with one or more sampling offsets matching the one or more image shifts to obtain the sequence of subframes. ### Claim 18 (depends on 16) The method of claim 16 wherein the sequence of subframes comprises n≥2 consecutive subframes, the method further comprising sequentially shifting each image pixel of the at least a portion of the image to n different locations in an image plane over the sequence of n consecutive subframes. ### Claim 19 (depends on 16) The method of claim 16 wherein the shifting comprises switching the image light between two orthogonal polarization states using one or more polarization switches, and steering the image light in dependence on the polarization state thereof using one or more polarization gratings. ### Claim 20 A display apparatus comprising: an electronic display system configured to transmit polarized light responsive to image data; a polarization switch configured to switch the polarized light between first and second orthogonal polarization states in synchronization with the electronic display refreshing the image data, and a polarization grating configured to diffract the polarized light of the first and second orthogonal polarization states at different diffraction angles for forming spatially offset images.