# US 11,029,459 B2 · Phase gratings with odd symmetry for high-resolution lensless optical sensing > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,029,459 B2 - Document ID: US11029459B2 - Status: Granted - Kind: B2 - Application number: 15/953,597 - Filed: 2018-04-16 - Published: 2018-10-18 - Granted: 2021-06-08 - Earliest claimed: 2013-03-05 - Assignees: Rambus Inc. - Applicants: Rambus Inc. - Inventors: Patrick R. Gill; David G. Stork - Web page: https://patentgrep.com/patent/US11029459B2 ## CPC - G02B 5/3083: {Birefringent or phase retarding elements (G02B5/3008, G02B5/3016 take precedence; systems for polarisation control G02B27/286; manufacturing phase modulating patterns by lithographic processes G03F7/001)} - G02B 5/1842: {Gratings for image generation (G02B5/1847 takes precedence)} - G02B 5/1871: {Transmissive phase gratings} - G02B 27/4205: {having a diffractive optical element [DOE] contributing to image formation, e.g. whereby modulation transfer function MTF or optical aberrations are relevant} - G02B 27/46: Systems using spatial filters - H04N 23/951: by using two or more images to influence resolution, frame rate or aspect ratio - H04N 25/00: Circuitry of solid-state image sensors [SSIS]; Control thereof - H10F 39/024: {of coatings or optical elements} - H10F 39/806: {Optical elements or arrangements associated with the image sensors} - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION - H10F: INORGANIC SEMICONDUCTOR DEVICES SENSITIVE TO INFRARED RADIATION, LIGHT, ELECTROMAGNETIC RADIATION OF SHORTER WAVELENGTH OR CORPUSCULAR RADIATION ## Abstract Image-sensing devices include odd-symmetry gratings that cast interference patterns over a photodetector array. Grating features offer considerable insensitivity to the wavelength of incident light, and also to the manufactured distance between the grating and the photodetector array. Photographs and other image information can be extracted from interference patterns captured by the photodetector array. Images can be captured without a lens, and cameras can be made smaller than those that are reliant on lenses and ray-optical focusing. ## Claims ### Claim 1 A transmissive phase grating comprising: a plurality of boundaries extending radially over an area, each boundary defined by adjacent and transparent first and second features symmetrically disposed on either side of that boundary; a first filter covering a first portion of the area; and a second filter covering a second portion of the area. ### Claim 2 (depends on 1) The transmissive phase grating of claim 1, wherein the first filter comprises a first polarization filter of a first orientation and the second filter comprises a second polarization filter of a second orientation different from the first orientation. ### Claim 3 (depends on 2) The transmissive phase grating of claim 2, wherein the first orientation is perpendicular to the second orientation. ### Claim 4 (depends on 1) The transmissive phase grating of claim 1, wherein the area is round. ### Claim 5 (depends on 1) The transmissive phase grating of claim 1, wherein the boundaries are curved. ### Claim 6 (depends on 1) The transmissive phase grating of claim 1, wherein the boundaries are discontinuous. ### Claim 7 (depends on 1) The transmissive phase grating of claim 1, each boundary to induce, at a position underlying that boundary, for light in a wavelength band of interest incident the transmissive phase grating and normal to a transverse plane of the grating, a half-wavelength shift of the light through the transparent first feature with respect to the light passing through the adjacent transparent second feature. ### Claim 8 (depends on 7) The transmissive phase grating of claim 7, wherein the boundaries are discontinuous. ### Claim 9 (depends on 1) The transmissive phase grating of claim 1, wherein the first filter surrounds the second filter. ### Claim 10 (depends on 9) The transmissive phase grating of claim 9, wherein the first filter and the second filter are concentric. ### Claim 11 (depends on 9) The transmissive phase grating of claim 9, further comprising a third filter covering a third portion of the area. ### Claim 12 (depends on 11) The transmissive phase grating of claim 11, wherein the third filter surrounds the first filter and the second filter. ### Claim 13 (depends on 12) The transmissive phase grating of claim 12, wherein the first filter is a blue filter, the second filter is a green filter surrounding the first filter, and the third filter is a red filter surrounding the green filter. ### Claim 14 (depends on 1) The transmissive phase grating of claim 1, wherein the area is of a plane. ### Claim 15 An imaging device comprising: a photodiode array; a transmissive phase grating with diverging boundaries extending over an area of the photodiode array, each boundary defined by immediately adjacent and transparent first and second features symmetrically disposed on either side of that boundary; a first filter covering a first portion of the area; and a second filter covering a second portion of the area. ### Claim 16 (depends on 15) The imaging device of claim 15, wherein the first filter comprises a first polarization filter of a first orientation and the second filter comprises a second polarization filter of a second orientation different from the first orientation. ### Claim 17 (depends on 16) The imaging device of claim 16, wherein the first orientation is perpendicular to the second orientation. ### Claim 18 (depends on 15) The imaging device of claim 15, wherein the first filter surrounds the second filter. ### Claim 19 (depends on 18) The transmissive phase grating of claim 18, wherein the first filter and the second filter are concentric.