Pathology and / or ocular-side-dependent illumination for retinal imaging

Abstract

To obtain a high-quality image. **Solution**: The retinal imaging system includes an eyepiece lens assembly, an image sensor adapted to obtain a retinal image of an eye through the eyepiece lens assembly, and a controller communicatively coupled to the image sensor. The controller, when executed, causes the retinal imaging system to obtain a point of interest (POI) related to the eye or an indicator of the laterality of the eye, select an eye box position for the eye box of the retinal imaging system based at least in part on the POI or the laterality of the eye, and obtain a retinal image of the eye when the eye is determined to be positioned within the eye box. The eye box corresponds to a boundary region within a space defined with respect to the eyepiece lens assembly.

Description

Technical Field

[0001] (Cross - reference to Related Applications) This application claims priority to U.S. Patent Application No. 63 / 345,258, filed May 24, 2022, the content of which is incorporated herein by reference.

[0002] The present disclosure generally relates to retinal imaging technology, and specifically, but not exclusively, to illumination technology for retinal imaging.

Background Art

[0003] Retinal imaging is part of a basic eye examination for screening, in - field diagnosis, and progression monitoring of many retinal diseases. High - fidelity retinal images are important for accurate screening, diagnosis, and monitoring. Illuminating the inner surface of the back of the eye (i.e., the retina) through the pupil brightens the image, but when the retinal camera and the illumination source are not properly aligned with the eye, optical aberrations or image artifacts such as corneal reflex, iris reflex, lens flare, clouding, or pupil shadow are often generated. Simply increasing the brightness of the illumination does not overcome these problems; rather, the optical artifacts become more prominent, and the goal of improving image fidelity is compromised.

[0004] Therefore, camera alignment is very important. Especially in conventional retinal cameras, since it is necessary to block the above - mentioned harmful image artifacts, typically, the eye box is limited. Referring to FIG. 1A, the eye box 100 of the retinal camera 105 is typically a boundary region within a three - dimensional space defined with respect to the eyepiece 110 of the retinal camera 105. In order to obtain an acceptable image of the retina, a specific part (e.g., the center) of the pupil 115 or the cornea of the eye needs to be present therein. Due to the small size of the conventional eye box, it is difficult to align the retinal camera, and it often burdens the interaction with the patient during the alignment process.

[0005] Conventional retinal camera systems (such as the retinal camera 105) use a single eyebox 100 with a single position (defined relative to the eyepiece 110 of the camera system), from which both the left and right eyes are imaged. However, this single position is a compromise that is not optimized for individual eyes and furthermore, it does not take into account the need to obtain higher quality images in specific areas of interest within the left and / or right eyes to help physicians screen, diagnose, monitor, or treat specific eye lesions. [Brief explanation of the drawing]

[0006] Non-limiting and non-exclusive embodiments of the present invention are described with reference to the following figures, where similar reference numerals refer to similar parts throughout the various figures unless otherwise specified. Not all instances of elements are necessarily labeled, so as not to confuse the drawings where appropriate. The drawings are not necessarily to scale, and instead the emphasis is on illustrating the principles described. [Figure 1A] (Prior Art) A single eyebox used by a conventional retinal imaging system to examine both the left and right eyes is shown. [Figure 1B] (Prior Art) A single eyebox used by a conventional retinal imaging system to examine both the left and right eyes is shown. [Figure 2A] The image shows a retinal image of the left eye with various image artifacts, according to one embodiment of the present disclosure. [Figure 2B] This image shows a retinal image of the right eye free of image artifacts, according to one embodiment of the present disclosure. [Figure 3A] One embodiment of the present disclosure shows how to move the eyebox of a retinal imaging system to different positions in response to laterality of the eye and / or point of interest (POI). [Figure 3B] One embodiment of the present disclosure shows how to move the eyebox of a retinal imaging system to different positions in response to laterality of the eye and / or point of interest (POI). [Figure 4]This disclosure describes a retinal imaging system that can use a dynamic eyebox position according to one embodiment of this disclosure. [Figure 5] One embodiment of the present disclosure shows a dynamic ring illuminator for illuminating the retina during retinal imaging. [Figure 6] This flowchart shows a process for capturing a retinal image using a dynamic eyebox position, fixation target, and illumination pattern based on laterality and / or point of interest (POI) of the eye, according to one embodiment of the present disclosure. [Figure 7A] One embodiment of the present disclosure shows a dynamic fixation target including an eyebox reference and an eye position reference that moves the eye to a specific eyebox and alignment. [Figure 7B] One embodiment of the present disclosure shows a dynamic fixation target including an eyebox reference and an eye position reference that moves the eye to a specific eyebox and alignment. [Modes for carrying out the invention]

[0007] Embodiments of apparatus, systems, and methods of operation for a retinal imaging system that adapts the eyebox position based on a point of interest (POI) and / or laterality of the eye are described herein. Numerous specific details are described below to provide a complete understanding of the embodiments. However, those skilled in the art will recognize that the techniques described herein may be carried out without one or more of the specific details, or using other methods, components, materials, etc. In other cases, well-known structures, materials, or operations are not shown or described in detail to avoid obscuring specific embodiments.

[0008] Throughout this specification, the term "one embodiment" means that any particular feature, structure, or characteristic described in relation to an embodiment is included in at least one embodiment of the present invention. Therefore, the phrases "in one embodiment" or "in an embodiment" appearing in various places throughout this specification do not necessarily all refer to the same embodiment. Furthermore, any particular feature, structure, or characteristic may be combined in any preferred manner in one or more embodiments.

[0009] High-fidelity retinal imaging is crucial for screening, diagnosing, and monitoring many retinal diseases. For this reason, it is desirable to reduce or eliminate instances of image artifacts that obstruct or otherwise impair portions of the retinal image. This is particularly true when a specific region of interest in a particular eye (e.g., the right or left eye) needs to be clearly imaged to screen, diagnose, monitor, or treat a specific ocular lesion. Conventional retinal imaging systems use an eyebox in a fixed eyebox position, which is not only fixed to a given eye but also across both the left and right eyes.

[0010] Figures 2A and 2B show exemplary retinal images of the left eye 200 and the right eye 201 (as seen from the perspective of a physician or retinal imaging system). As seen in Figures 2A and 2B, anatomical features (e.g., macula 205, fovea 210, optic disc 215, retinal venules 220, and retinal arterioles 225) are inverted around the vertical axis, altering the relative arrangement of these anatomical features between eyes 200 and 201. Thus, important anatomical features in each eye 200 or 201 have different arrangements depending on the laterality of the eye. If high-quality images of specific anatomical features are desired, the optimal eyebox position and illumination pattern may not be the same between eyes 200 and 201. Similarly, different lesions require good visualization of different parts of the eye. For example, the diagnosis and treatment of diabetic retinopathy is better performed by good visualization of the macula 205, and the diagnosis and treatment of glaucoma is better performed by good visualization of the optic disc 215. Therefore, retinal imaging for the purpose of screening, diagnosing, monitoring, and treating ophthalmic lesions can also be aided by adjusting the eyebox position and illumination pattern based on points of interest (POIs) to ensure the best possible images of the relevant retinal region.

[0011] The desirability of dynamically selected eyebox positions and / or illumination patterns is further highlighted by Figure 2A. As illustrated, retinal imaging may be subject to multiple image artifacts, including reflections230, pupillary shadows235, haze240, or others. These image artifacts can occur when stray light and harmful reflections from the illumination source enter the imaging path due to a misalignment between the retinal imaging system and the eye that is smaller than optimal, and are ultimately captured by the image sensor in retinal image light. Misalignment (or suboptimal alignment) can lead to harmful corneal / iris reflections, refractive scattering from the lens, occlusion of the imaging aperture, optical aberrations due to off-axis passage through the lens, obstruction of imaging light by the iris, and / or other problems. If these image artifacts obstruct areas of interest particularly relevant to the screening, diagnosis, or treatment of points of interest (POIs), the disease may go unnoticed or be improperly treated. Therefore, by selectively positioning eye boxes and customized illumination patterns based on ocular laterality and / or points of interest (POIs), retinal images can be improved by placing these artifacts in less relevant locations and / or by completely reducing or eliminating them. In some cases, eye box positions that achieve 100% removal of image artifacts are not easily or readily achievable. In such cases, dynamic fixation targets that encourage the eye to move to multiple different eye box positions using multiple different illumination patterns can encourage the patient's eye to rotate or align to multiple different directions / positions. Certain image artifacts may not be completely removed from all or any of the multiple retinal images, but the patient's eye is instructed to rotate / move so that each region of interest of the retina is clearly imaged in at least one retinal image. The multiple retinal images can then be combined or stacked to completely remove image artifacts from the composite retinal image, at least in regions of interest related to ocular laterality and / or POIs.

[0012] Figures 3A and 3B illustrate, according to one embodiment of the present disclosure, the movement of the eyebox of the retinal imaging system 300 to different positions depending on the laterality of the eye and / or point of interest (POI). As illustrated, retinal imaging of the right eye can be effectively provided using eyebox 301, which is offset to the left (e.g., shifted 1.5 mm to the left from the center), while retinal imaging of the left eye can be effectively provided using eyebox 302, which is offset to the right (e.g., shifted 1.5 mm to the right from the center). These lateral offsets of the eye can improve the visualization of important anatomical features. This selective adjustment of the eyebox position can also be indexed against a point of interest (or a combination of a point of interest and laterality of the eye) if the examination of a particular retinal region is of particular interest to screening, diagnosing, and treating a given ocular lesion. While Figures 3A and 3B illustrate eyeboxes 301 and 302 using cubes or rectangles, it should be understood that the eyeboxes can be of various different three-dimensional shapes (e.g., spherical, elliptical, etc.).

[0013] Figure 4 shows a retinal imaging system 400 according to one embodiment of the present disclosure, which can use a dynamic eyebox position based on POI and / or ocular eccentricity. The illustrated embodiment of the retinal imaging system 400 includes an illuminator 405, an image sensor 410 (also called a retinal image sensor), a controller 415, a user interface 420, a dynamic fixation target 425, an alignment tracking camera system 430, and an optical relay system. The illustrated embodiment of the optical relay system includes lens assemblies 435, 440, 445, and a beam splitter 450. Lens assembly 435 may also be called an eyepiece lens assembly 435. The illustrated embodiment of the illuminator 405 includes a dynamic ring illuminator with a central aperture 455. The illustrated embodiment of the dynamic fixation target 425 includes a display 426 that outputs a dynamic fixed image 427 which may include one or more reference markers 428 representing relative eyebox and / or eye positions.

[0014] The optical relay system functions to direct (e.g., pass through or reflect) the illumination light 480 output from the illuminator 405 along the illumination path through the pupil of the eye 470 to illuminate the retina 475, while directing the image light 485 (i.e., the retinal image) from the retina 475 along the imaging path to the image sensor 410. The image light 485 is formed by the scattered reflection of the illumination light 480 from the retina 475. In the illustrated embodiment, the optical relay system further includes a beam splitter 450, which passes at least a portion of the image light 485 to the image sensor 410, while optically coupling the dynamic fixation target 425 to the eyepiece assembly 435 and directing the dynamic fixed image 427 output from the display 226 to the eye 470. The beam splitter 450 may be implemented as a polarizing beam splitter, a non-polarizing beam splitter (e.g., 90% transmission and 10% reflection, 50 / 50 beam splitter, etc.), a multilayer dichroic beam splitter, or other. The optical relay system includes several lenses, such as lenses 435, 440, and 445, which focus on various optical paths as needed. For example, lens 435 may include one or more lens elements that collectively form an eyepiece lens assembly that is displaced from the cornea of ​​the eye 470 by the eye relief 495 during operation. Lens 440 may include one or more lens elements for focusing the image light 485 onto the image sensor 410. Lens 445 may include one or more lens elements for focusing the dynamic fixed image 427. It should be understood that the optical relay system can be implemented using a large and diverse array of optical elements (e.g., lenses, reflective surfaces, diffracting surfaces, etc.) and may differ from the configuration shown in Figure 4.

[0015] In one embodiment, the dynamic fixation image 427 output from the display 426 represents a fixation point from which the patient can adjust their focus and fix their gaze. The dynamic fixation image 427 may be an image of a plus sign, bullseye, cross, target, circle, or other shape or set of shapes (see, for example, Figures 7A and 7B). In the illustrated embodiment, the dynamic fixation target 425 is implemented as a virtual image output from the display 426. However, the fixation point may be implemented in various other ways, including a physical target(s) that is actuated or optically manipulated. The dynamic fixation target 425 can not only help the patient achieve alignment between the retinal imaging system 400 and the eye 470 by providing visual feedback, but can also give the patient a fixation point / fixation target from which the patient can adjust and stabilize their visual acuity. The dynamic fixation target can be moved as needed by translating the image of the fixation target (e.g., reference marker 428) around the display 426 (e.g., moving the symbol or image up / down or left / right on the display 426). The display 426 can be implemented using a variety of technologies, including liquid crystal displays (LCDs), light-emitting diodes (LEDs), various illuminated shapes (e.g., illuminated crosses or concentric circles), or others. Of course, dynamic fixation targets can be implemented in ways other than virtual images on the display. For example, the dynamic fixation target may be a physically manipulated physical object (e.g., a crosshair).

[0016] The controller 415 is coupled to the image sensor 410, the display 426, the illuminator 405, and the alignment tracking camera system 430 to integrate their operations. The controller 415 may include software / firmware logic, hardware logic (e.g., application-specific integrated circuits, field-programmable gate arrays, etc.), or a combination of software and hardware logic, running on a microcontroller. Figure 4 shows the controller 415 as different functional elements, but the logical functions performed by the controller 415 may be distributed across several hardware elements. The controller 415 may further include input / output (I / O) ports, a communication system, or other components. The controller 415 is coupled to the user interface 420 to receive user input and provide user control over the retinal imaging system 400. The user interface 420 may include one or more buttons, dials, joysticks, feedback displays, indicator lights, etc.

[0017] The image sensor 410 can be implemented using various imaging techniques, such as a complementary metal-oxide-semiconductor (CMOS) image sensor, a charge-coupled device (CCD) image sensor, or others. In one embodiment, the image sensor 410 includes an onboard memory buffer or attached memory for storing / buffering retinal images. In one embodiment, the image sensor 410 may also include an integrated image signal processor (ISP) to enable high-speed digital processing of retinal images buffered in the internal memory. The onboard image buffer and ISP can facilitate high-frame-rate image burst capture, image processing, image stacking, and output of high-quality composite retinal images. The integrated ISP may be considered a decentralized component of the controller 415.

[0018] The alignment tracking camera system 430 operates to track the lateral alignment (or misalignment) and relief offset between the retinal imaging system 400 and the eye 470, particularly between the eyepiece assembly 435 and the eye 470. The system 430 can operate using a variety of different techniques to track the relative placement of the eye 470 with respect to the retinal imaging system 400, including pupil tracking or iris tracking. In the illustrated embodiment, the system 430 includes two cameras positioned on either side of the eyepiece assembly 435 to enable triangulation and obtain X, Y, and Z global placement information regarding the pupil or iris. In one embodiment, the system 430 also includes one or more infrared (IR) emitters to track the eye 470 using IR light while a retinal image is being acquired using a burst of visible spectrum light output from the illuminator 405 through the eyepiece assembly 435. In such an embodiment, an IR filter can be positioned within the image path to filter the IR tracking light. In some embodiments, the tracking illumination is temporarily offset from the image acquisition by the white light burst.

[0019] The lateral eye alignment may be measured by the system 430 via the retinal image acquired by the image sensor 410 or separately / additionally. In the illustrated embodiment, the system 430 is positioned externally to view the eye 470 from outside the eyepiece assembly 435. In other embodiments, the system 430 may be optically coupled using optical relay components to view and track the eye 470 through the eyepiece assembly 435.

[0020] Figure 5 shows a dynamic ring illuminator 500 for illuminating the retina 475 during retinal imaging, according to one embodiment of the present disclosure. The dynamic ring illuminator 500 represents one possible implementation of the illuminator 405. The illustrated embodiment of the dynamic ring illuminator 500 includes a ring of light sources 505 surrounding a central aperture 510, the central aperture also being surrounded by a baffle 515 (e.g., a cone, a light shade, etc.) that blocks stray or off-axis light. The light sources 505 are positioned around the central aperture 510 with various radial and axial offsets. The light sources 505 can be operated independently by a controller 415 to emit selective illumination patterns. These patterns may be selected based on the position of the eye relative to the eyepiece 435, such as determined by pupil / iris tracking using a system 430 or by retinal tracking using an image sensor 410. The patterns may also be selected depending on the laterality and / or point of interest of the eye. In the illustrated embodiments, each light source 505 includes two emitters: a white light emitter for color retinal images and an IR emitter for IR images. Since the human eye responds little to no to IR light, the IR emitter may be used for eye tracking and acquisition of preliminary images (e.g., for determining laterality of the eye) before acquiring a full-color burst image. The white light emitter may burst white light for several hundred milliseconds, enabling the acquisition of a sequence of full-color images before physiological responses cause blinking and / or excessive pupillary constriction.

[0021] Referring to FIG. 4, during operation, the controller 415 operates the illuminator 405 and the retinal image sensor 410 to capture one or more retinal images. The illumination light 480 is directed to pass through the pupil of the eye 470 to illuminate the retina 475. The scattered reflections from the retina 475 are directed back through the aperture 455 along the image path to the image sensor 410. When the eye 470 is properly aligned within the selected eye box of the system 400, the aperture 455 operates to block harmful reflections and light scattering that could otherwise adversely affect the retinal image while allowing the image light itself to pass through. Prior to capturing the retinal image, the controller 415 operates the display 426 to output a dynamic fixation image 427 for guiding the patient's line of sight. One or more initial or preliminary eye images (e.g., initial alignment images) from either the image sensor 410 or the alignment tracking camera system 430 are acquired and analyzed to determine the lateral alignment between the eye 470 and the eyepiece lens assembly 435. These initial alignment images can be illuminated with infrared (IR) light output from the illuminator 405 (or an independent illuminator associated with the alignment tracking camera system 430) so as not to trigger the iris constriction response that narrows the imaging path to the retina 475. In other embodiments, conventional white light or other colored light is used to acquire the initial alignment images. The initial alignment images are then analyzed by the controller 415 to identify any misalignment, relocate the eye position reference within the dynamic fixation image 427 to prompt proper eye positioning with respect to the selected eye box, and then trigger the acquisition of one or more subsequent eye images (e.g., retinal image bursts) by the image sensor 410. The subsequent images can be full-color images, specific color images, or IR images as needed.

[0022] Figure 6 is a flowchart of process 600 for capturing a retinal image using a dynamic eyebox position, fixation target, and illumination pattern based on laterality and / or lesion of interest of the eye, according to one embodiment of the present disclosure. The order in which some or all of the process blocks appear in process 600 should not be considered limiting. Rather, those skilled in the art who are interested in the present disclosure will understand that some of the process blocks may be performed in various not-executed orders, or even in parallel.

[0023] In process block 605, the retinal imaging process is initiated. Initiation may include the user pressing a power button on the user interface 420. After power-on, the controller 415 acquires an index of POIs related to the eye being examined. This index may be requested via the user interface 420 or entered by the user / operator of the retinal imaging system 400. Exemplary POIs may include diabetic retinopathy, glaucoma, or others. Based on the determination of a specific POI, the controller 405 may configure the eyebox position and / or illumination pattern to best examine the portion(s) of the retina 475 most relevant to the selected specific ophthalmic disease.

[0024] In process block 615, illumination is enabled to obtain a preliminary eye image to facilitate eye tracking and / or determine laterality of the eye. In one embodiment, this initial illumination is IR illumination output from the IR emitter of the alignment tracking camera system 430 and / or light source 505. IR illumination reduces the likelihood that the light will produce a physiological response that causes iris constriction before a primary retinal image is acquired.

[0025] In process block 620, the laterality of the eye (i.e., right eye or left eye) is determined. The laterality of the eye may be manually entered via the user interface 420, or it may be automatically determined by the controller 415 based on image analysis and feature recognition performed on a preliminary image of the eye. The preliminary image may be an IR retinal image acquired via the image sensor 410 and / or an eye image acquired by the alignment tracking camera system 430.

[0026] Once ocular laterality and / or a POI are determined, the eyebox position of the retinal imaging system 400 can be selected (process block 625). The determination may be based on either or both of these factors. The eyebox position is the position of the eyebox of the imaging system, which is the boundary region in space defined relative to the eyepiece assembly. As shown in Figures 3A and 3B, the eyebox position for the right eye is generally offset to the left (e.g., approximately 1.5 mm to the left), while the eyebox position for the left eye is generally offset to the right (e.g., approximately 1.5 mm to the right). Identification of a specific POI may be used to further refine this eyebox position in addition to the ocular default. For example, identification of diabetic retinopathy would involve translating the eyebox position to center the retinal image on the macula 205 of a given eye, and identification of glaucoma would involve translating the eyebox position to center the retinal image on the optic disc 215 of a given eye. Of course, depending on the POI, other translations and eye position may be focused on. In addition (or alternatively), these lesion-based offsets serve to move image artifacts away from the retinal region of interest, as determined based on the POI.

[0027] Once an eyebox position is selected, the fixed position of the dynamic fixation target 425 may be configured to prompt the eye 470 to adjust its position and / or gaze direction accordingly (process block 630). Figures 7A and 7B show exemplary dynamic fixation images 705 and 710 output from the display 426, respectively. Both dynamic fixation images 705 and 710 include an eyebox reference 715 and an eye position reference 720. The eyebox reference 715 is a virtual marker on the display 426 that is positioned on the display 426 based on the selected eyebox position and represents the eyebox itself. The eye position reference 720 is a virtual marker on the display 426 that represents the patient's pupil, and its position on the display 426 changes in real time as the user attempts to align their eye with the eyepiece 435. In other words, the position of the eye position reference 720 tracks the eye position relative to the eyepiece 435 based on the output from the alignment tracking camera system 430 or the image sensor 410 (process block 635). In various embodiments, the alignment tracking camera system 430 may be used for overall eye alignment based on pupil / iris tracking, while the image sensor 410 may be used for fine eye alignment based on retinal tracking. The dynamic fixation images 705 and 710 may operate as a kind of game in which the patient is instructed to align two circular markers concentrically by moving their eyes relative to the eyepiece assembly 435. Eyebox alignment is achieved when the eye position reference 720 is moved within the eyebox reference 714, as shown in Figure 7B (determination block 640). By dynamically moving the eye position reference 720, the fixation target is adjusted and the user is prompted or moved to align as they attempt to align the reference markers concentrically (process block 645). Of course, other alignment / fixation images may be implemented to facilitate threshold alignment as needed to obtain a satisfactory retinal image.

[0028] Once threshold alignment is achieved (determination block 640), the illuminator 405 is configured by the controller 415 to select an appropriate illumination pattern for retinal imaging. The illumination pattern may be selected based on pupil position and pupil size to reduce image artifacts and optimize retinal image quality (process block 650). In one embodiment, a lookup table (LUT) can index the illumination pattern to pupil position and / or pupil size. In yet another embodiment, the LUT may further index the illumination pattern to points of interest and / or ocular unilaterality for further pattern refinement. For example, the illumination pattern may consider not only the current position of the eye relative to the eyepiece assembly 435 but also anatomical features associated with a given lesion, and thus select an illumination pattern that shifts various image artifacts from those anatomical features in the retinal image. This may be considered a finer illumination pattern refinement in addition to illumination pattern selection based on real-time eye position tracking.

[0029] Once threshold alignment is achieved (determination block 640) and an appropriate illumination pattern is selected (process block 650), the illuminator 405 illuminates the retina 475 through the pupil. This illumination may be a white light flash, but the specific wavelength used for illumination (e.g., broadband white light, IR light, near-IR, etc.) may be adjusted to suit a specific lesion or application. The illumination flash in process block 655 may last only for a period (e.g., 200 milliseconds) that is less than or equal to the physiological response time of a human (e.g., pupil constriction or blinking). While the illumination is active, one or more retinal images are acquired (process block 660). In one embodiment, the acquisition of bursts of retinal images (e.g., 5, 10, 20, 50, 100 images) is triggered between illumination windows and while the eye remains within the selected eyebox, as determined from real-time feedback from the alignment tracking camera system 430 (or image sensor 410).

[0030] The bursts of retinal images may be buffered on a camera chip including an image sensor 410, allowing an image signal processor (ISP) to quickly analyze the quality of the acquired retinal images. The ISP may be considered a component of a controller 415 (e.g., a distributed offload computing engine) positioned near the image sensor 410 to enable high-speed image processing. If the image is obscured, unclear, or unsuitable, process 600 returns to process block 630 and repeats the relevant portion of process 600. However, if the acquired images are deemed sufficient collectively to adequately capture the region of interest related to the point of interest (POI), the retinal images may be combined (process block 670) to generate, output, and store a high-quality composite image (process block 675). Various different combining techniques, such as image stacking or others, may be implemented.

[0031] The processes described above relate to computer software and hardware. The techniques described may constitute machine-executable instructions, embodied in tangible or non-temporary machine (e.g., computer)-readable storage media, which, when executed by a machine, cause the machine to perform the described actions. Furthermore, the processes may be embodied in application-specific integrated circuits ("ASICs") or other hardware.

[0032] A tangible machine-readable storage medium includes any mechanism that provides (i.e., stores) information in a non-temporary form accessible by a machine (e.g., a computer, network device, personal information terminal, manufacturing tool, or any device having a set of one or more processors). For example, a machine-readable storage medium includes recordable / non-recordable media (e.g., read-only memory (ROM), random access memory (RAM), magnetic disk storage media, optical storage media, flash memory devices, etc.).

[0033] The above description of exemplary embodiments of the Invention, including those described in the abstract, is not intended to be exhaustive or to limit the Invention to the exact form disclosed. While specific embodiments and examples of the Invention are described herein for illustrative purposes, various modifications are possible within the scope of the Invention, as will be apparent to those skilled in the art.

[0034] These modifications can be made to the present invention in light of the detailed description above. In general, the terms used in the following claims should not be construed as limiting the invention to any particular embodiment disclosed herein. Rather, the scope of the invention should be determined entirely by the following claims, which should be interpreted in accordance with established principles of claim interpretation.

Claims

1. A retinal imaging system, Eyepiece assembly and An image sensor adapted to acquire a retinal image of the eye through the aforementioned eyepiece assembly, The image sensor includes a controller which is communicably coupled to the image sensor, and the controller, when executed, includes logic that causes the retinal imaging system to perform an action, and the action is To obtain indicators of point of interest (POIs) related to the eye, Selecting an eyebox position for the eyebox of the retinal imaging system, at least in part, based on the POI, wherein the eyebox position corresponds to a boundary region in space defined with respect to the eyepiece assembly. When it is determined that the eye is positioned within the eye box, the retinal image of the eye is acquired. A retinal imaging system, including a retinal imaging system.

2. The controller, when executed, includes further logic that causes the retinal imaging system to perform additional operations, the additional operations being: To determine whether the lateral deviation of the aforementioned eye is in the right eye or the left eye, The retinal imaging system according to claim 1, comprising selecting the eyebox position at least partially based on both the point of interest (POI) and the laterality of the eye.

3. The retinal imaging system according to claim 2, wherein the eyebox position differs between the right eye and the left eye.

4. The retinal imaging system according to claim 2, wherein the bias of the eye is determined at least in part based on manual user input.

5. The retinal imaging system according to claim 2, wherein the laterality of the eye is automatically determined by the retinal imaging system based at least partially on a preliminary image of the eye.

6. The system further includes an illuminator coupled to the controller and positioned to illuminate the eye, wherein the controller, when executed, includes further logic causing the retinal imaging system to perform additional operations, the additional operations being: The retinal imaging system according to claim 2, comprising adjusting the illumination pattern output from the illuminator based at least partially on the point of interest (POI) or the laterality of the eye.

7. The retinal imaging system according to claim 6, wherein the illuminator includes a dynamic ring illuminator that surrounds an optical path extending between the eyepiece assembly and the image sensor in order to illuminate the retina of the eye through the eyepiece assembly.

8. The retinal imaging system according to claim 1, wherein the eyebox position associated with the point of inclusion (POI) indicated as diabetic retinopathy is different from the eyebox position associated with the POI indicated as glaucoma.

9. The system further includes the dynamic fixation target optically coupled to the eyepiece assembly so that the dynamic fixation target can be viewed through the eyepiece assembly, the dynamic fixation target electrically coupled to the controller, and the controller includes further logic that, when executed, causes the retinal imaging system to perform additional operations, the additional operations being The retinal imaging system according to claim 1, comprising adjusting the fixed position of the dynamic fixation target based at least partially on the point of interest (POI) or the eyebox position selected for the POI.

10. The dynamic fixation target includes a dynamic fixed image output from a display, and the dynamic fixed image is An eyebox reference rendered to a first arrangement on the display selected at least partially based on the POI and the eyebox position, The retinal imaging system according to claim 9, comprising an eye position reference rendered in a second arrangement on the display, at least in part on tracking the real-time position of the eye.

11. The system further includes an alignment tracking camera system coupled to the controller for tracking the real-time positioning of the pupil or iris of the eye, wherein the controller includes further logic that, when executed, causes the retinal imaging system to perform additional actions, the additional actions being The retinal imaging system according to claim 1, further comprising triggering the acquisition of a burst of retinal images, including the retinal image, using the image sensor when it is determined that the real-time position of the pupil or iris is within the eye box based on feedback from the alignment tracking camera system.

12. A method for imaging the retina of an eye using a retinal imaging system comprising an eyepiece assembly and an image sensor adapted to acquire a retinal image of the eye through the eyepiece assembly, To determine whether the lateral deviation of the eye is in the right eye or the left eye, Selecting an eyebox position for the eyebox of the retinal imaging system, at least partially based on the aforementioned laterality, wherein the eyebox position corresponds to a boundary region in space defined with respect to the eyepiece assembly. A method comprising obtaining a retinal image of the eye when it is determined that the eye is positioned within the eye box.

13. To obtain indicators of point of interest (POIs) related to the eye, The method according to claim 12, further comprising selecting the eyebox position at least partially based on both the POI and the unilaterality of the eye.

14. The method according to claim 13, further comprising adjusting the illumination pattern for illuminating the eye based at least partially on the unilaterality of the eye and the point of interest (POI).

15. The method according to claim 14, wherein the illumination pattern is output by a dynamic ring illuminator surrounding an optical path extending between the eyepiece assembly and the image sensor to illuminate the retina of the eye through the eyepiece assembly.

16. The method according to claim 13, further comprising adjusting the fixed position of the dynamic fixed image that can be seen through the eyepiece assembly based on at least one of the POI or the eccentricity of the eye.

17. Adjusting the fixed position of the dynamic fixed image Displaying an eyebox criterion for a first arrangement in the dynamic fixed image, wherein the first arrangement is selected based on at least one of the POI or the laterality of the eye. The method according to claim 16, comprising displaying an eye position reference for a second arrangement in the dynamic fixed image, wherein the second arrangement is determined at least in part on tracking the real-time position of the eye.

18. The method according to claim 12, wherein the bias of the eye is determined at least in part based on manual user input.

19. The method according to claim 12, wherein the laterality of the eye is automatically determined by the retinal imaging system based at least partially on a preliminary image of the eye.

20. Using a separate alignment tracking camera system from the aforementioned image sensor, the real-time positioning of the pupil or iris of the eye is tracked. The method according to claim 12, further comprising using the image sensor to trigger the acquisition of a burst of retinal images including the retinal image when it is determined, based on feedback from the alignment tracking camera system, that the real-time position of the pupil or the iris is within the eye box.

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