# US 2017/0280995 A1 · Wide field fundus camera > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2017/0280995 A1 - Document ID: US20170280995A1 - Status: Published application - Kind: A1 - Application number: 15/510,923 - Filed: 2015-09-14 - Published: 2017-10-05 - Earliest claimed: 2014-09-14 - Assignees: Retivue, LLC - Applicants: Retivue LLC - Inventors: Paul A. Yates; Ming Lai - Web page: https://patentgrep.com/patent/US20170280995A1 ## CPC - A61B 3/125: with contact lenses - A61B 3/0008: {provided with illuminating means (A61B3/117, A61B3/14 take precedence)} - A61B 3/0025: {characterised by electronic signal processing, e.g. eye models} - A61B 3/12: for looking at the eye fundus, e.g. ophthalmoscopes (A61B3/13 takes precedence) - A61B 3/14: Arrangements specially adapted for eye photography - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) ## Abstract A wide field fundus camera is disclosed to implement multiple illumination beam projectors and to capture multiple retinal images at a various viewing angles to mimic wide field retinal examination with an indirect ophthalmoscope. The wide field fundus camera may incorporate a consumer image recording device with fast auto focusing so as to make the device quick to respond and easy to use. The wide field fundus camera may include narrow and broad slit beam illuminations to enhance autofocusing and imaging through less transparent crystalline lens and through haze due to Purkinje reflections from crystalline lens surfaces. Control of multiple illumination beam projectors in a programmable manner can be used to assess alignment of each illumination beam projector with the eye and to capture said multiple retinal images. Furthermore, a method is disclosed to montage said multiple retinal images into a single montage and to remove haze and reflections. ## Claims ### Claim at position 1 1-38. (canceled) ### Claim 39 A wide field fundus camera, comprising: an objective lens having a symmetric viewing axis and disposed to form a retinal image of wide field of view; an image recording device disposed to capture said retinal image of said wide field of view; a plurality of illumination beam projectors positioned around said viewing axis and each configured to project an illumination beam at a predetermined angle toward said objective lens; a first polarizer disposed in front of said image recording device, to define a polarization orientation; a set of second polarizers disposed each in front of a said illumination beam projector and oriented each to form a cross polarization condition with respect to said first polarizer to reject specular reflections of said illumination beams; and an electronic controller powering said plurality of illumination beam projectors and facilitating plurality of retinal images in a programmable manner. ### Claim 40 (depends on 39) The wide field fundus camera of claim 39, further comprising: a software algorithm implemented to process said plurality of retinal images and to stitch them into a wide field single image. ### Claim 41 (depends on 39) The wide field fundus camera of claim 39, wherein said objective lens includes an aspherical lens forming a field of view of 120 degrees or wider. ### Claim 42 (depends on 39) The wide field fundus camera of claim 39, wherein said image recording device is a consumer camera configured to provide automatic focusing and automatic exposure selection. ### Claim 43 (depends on 39) The wide field fundus camera of claim 39, wherein said illumination beam is delivered from a high power, high brightness white light LED. ### Claim 44 (depends on 39) The wide field fundus camera of claim 39, wherein said illumination beam is delivered from a high power, high brightness infrared LED. ### Claim 45 (depends on 39) The wide field fundus camera of claim 39, wherein said illumination beam is delivered from a low vergency beam projector. ### Claim 46 (depends on 39) The wide field fundus camera of claim 39, wherein said illumination beam is a slit beam. ### Claim 47 (depends on 39) The wide field fundus camera of claim 39, wherein said electronic controller is coupled with said image recording device via wireless electronics. ### Claim 48 A wide field fundus camera, comprising: an aspherical lens having a symmetric viewing axis and disposed to form a retinal image of wide field of view; a focusing lens positioned along said viewing axis and reimaging said retinal image to distance; an image recording device capable of auto focus and auto exposure and disposed behind said focusing lens to capture said retinal image of said wide field of view; a plurality of illumination beam projectors positioned around said viewing axis and each illumination beam projected at an angle toward said objective lens; a narrow illumination beam projected at an angle and away from pupil center to illuminate a small section on retina to facilitate auto focusing through less-transparent eye optics; a cross polarization system incorporated between said illumination beams and said image recording device, to reject specular reflections of said illumination beams; and an electronic controller powering said plurality of illumination beam projectors and facilitating plurality of retinal images in a programmable manner. ### Claim 49 (depends on 48) The wide field fundus camera of claim 48, further comprising: a processor circuit coupled to a memory circuit, said memory circuit including instructions that cause said processor circuit to receive imaging information corresponding to said plurality of retinal images and to provide a composite image including stitching together said plurality of retinal images into a single montage image. ### Claim 50 (depends on 48) The wide field fundus camera of claim 48, further comprising: a processor circuit coupled to a memory circuit, said memory circuit including instructions that cause said processor circuit to receive imaging information corresponding to said plurality of retinal images and to remove artificial reflection spots and lens haze from each of said plurality of retinal images. ### Claim 51 (depends on 48) The wide field fundus camera of claim 48, wherein said aspherical lens has a field of view of 120 degrees or greater on said retina. ### Claim 52 (depends on 48) The wide field fundus camera of claim 48, wherein said focusing lens comprises an achromatic lens. ### Claim 53 (depends on 48) The wide field fundus camera of claim 48, wherein said illumination beams are each a slit beam. ### Claim 54 (depends on 48) The wide field fundus camera of claim 48, wherein said narrow illumination beam is a narrowed slit beam. ### Claim 55 A method for providing a wide field fundus camera, comprising the steps of: providing an objective lens having a symmetric viewing axis and disposed to form a retinal image of said wide field of view; providing an image recording device disposed to capture said retinal image; providing plurality of illumination beam projectors positioned around said viewing axis and projected each an illumination beam at a predetermined angle with respect to said viewing axis; providing a cross polarization condition incorporated between said illumination beam projectors and said image recording device to reject specular reflections of said illumination beams. providing an electronic controller controlling said plurality of illumination beam projectors to control illumination power for each of said illumination beam projectors; powering said plurality of illumination beam projectors in a sequentially programmable manner; capturing plurality of fundus images synchronized with said illumination beam projectors in said sequential programmable manner; and providing a processor circuit coupled to a memory circuit, said memory circuit including instructions that cause said processor circuit to receive imaging information corresponding to said plurality of retinal images and to provide a composite image including stitching together said plurality of retinal images into a single montage image. ### Claim 56 (depends on 55) The method of claim 55, further comprising the steps of: providing a processor circuit coupled to a memory circuit, wherein said memory circuit includes instructions that cause said processor circuit to receive imaging information corresponding to said plurality of retinal images and capable of removing artificial reflection spots from each of said plurality of retinal images. ### Claim 57 (depends on 55) The method of claim 55, wherein said objective lens including an aspherical lens having a field of view of 120 degrees or wider on said retina. ### Claim 58 (depends on 55) The method of claim 55, wherein said illumination beams include slit beams.