Abstract: A computer-implemented method, system, and computer-readable medium, for determining a level of hypertension of a person. The method has steps of: acquiring image data defining a retinal image of a retina of the person that has been captured by a retinal imaging system; processing the image data to identify a plurality of vessel segments present in the retinal image; determining respective widths of vessel segments of at least a subset of the plurality of vessel segments present in the retinal image; and calculating, as a vascular summary metric, at least one average value or median value of the determined widths of the vessel segments present in the retinal image, to determine a level of hypertension by which the person has been affected.

Abstract: A method of processing a sequence of images of a retina acquired by an ophthalmic device to generate retinal position tracking information indicative of retina movement during acquisition. The method includes (i) receiving one or more images of the retina; (ii) calculating a cross-correlation between a reference image and an image based on the received image(s) to acquire an offset between the image and reference image; and repeating processes (i) and (ii) to acquire, as the tracking information, respective offsets for images that are based on the respective received image(s). Another step includes modifying the reference image during the repeating, by determining a measure of similarity between correspondingly located regions of pixels in two or more received images and accentuating features in the reference image representing structures of the imaged retina in relation to other features in the reference image based on the determined measure of similarity.

Abstract: An ophthalmic device including an illumination module which scans light across a region of the retina of an a eye when the pupil is disposed at a focal point of the illumination module. The ophthalmic device further comprises components (2, 3-1, 4-1) for: aligning the pupil with the focal point; monitoring a position of the pupil relative to the focal point and maintaining the alignment based on the monitored position; aligning a scan location of the illumination module on the retina to a target scan location while the alignment of the pupil with the focal point is being maintained, wherein the illumination module performs scan at the target scan location The ophthalmic device further maintains the scan location at the target scan location while the alignment of the pupil with the focal point is being maintained, using scan location correction information based on retinal feature information.

Abstract: A method of controlling an ophthalmic device operable to image an imaging region of a retina and concurrently illuminate an illumination region of the retina, the method including acquiring a reference retinal image by imaging a reference imaging area of the retina; designating a target in the reference retinal image; acquiring a current retinal image of an initial imaging region within the reference imaging area; moving the imaging region from the initial imaging region to a destination imaging region using the target and the reference retinal image, and acquiring a retinal image of the destination imaging region; illuminating the illumination region while the imaging region is the destination imaging region; acquiring one or more retinal images while the illumination module is being illuminated; and comparing a marker retinal image based on the one or more retinal image(s) with a comparison image based on the reference retinal image.

Abstract: An optical system comprising: an optical element having an optical property responsive to an applied signal, a variation of the optical property with the signal exhibiting hysteresis in a first range of values and no hysteresis in a second range of values of the signal; a memory storing data representing a hysteresis curve which indicates the variation of the optical property with increasing and decreasing values of the signal; and a controller which continuously controls the optical property by: generating, based on the stored data, a cyclic signal having a discontinuity in each cycle of the cyclic signal, and setting the discontinuity size in each cycle based on the stored data such that a part of the variation of the optical property with the cyclic signal coincides with a part of the variation represented by the stored data; and applying the cyclic signal to the optical element.

Abstract: A method of determining a geometrical measurement of a retina of an eye, comprising obtaining a two dimensional representation of at least a portion of the retina of the eye (34), deriving a geometrical remapping which converts the two dimensional representation of the retinal portion to a three dimensional representation of the retinal portion (36), using one or more coordinates of the two dimensional representation of the retinal portion to define the geometrical measurement to be taken of the retina on the two dimensional representation (38), using the geometrical remapping to convert the or each coordinate of the two dimensional representation of the retinal portion to an equivalent coordinate of the three dimensional representation of the retinal portion (40), and using the or each equivalent coordinate of the three dimensional representation of the retinal portion to determine the geometrical measurement of the retina of the eye (42).

Abstract: An ophthalmoscope (1) and method for scanning a fundus (23) of an eye (9), comprising a light system (3) which produces linear light, a scanner (5) which receives at least some of the linear light and is movable about a scan axis to produce a 1D scan of the at least some linear light, and a scan transfer system (7) which receives the 1D scan from the scanner and transfers the 1D scan to the eye, wherein the scanner is positioned in the ophthalmoscope such that it receives the at least some of the linear light substantially along the scan axis, the scan transfer system positioned in the ophthalmoscope such that a pupil of the eye is provided at a focal point of the system, and the scanner is positioned in the ophthalmoscope and the scan transfer system is configured to transfer the 1D scan from the scanner through the focal point at the eye pupil and onto the eye fundus.

Abstract: A method of determining a geometrical measurement of a retina of an eye, comprising obtaining a two dimensional representation of at least a portion of the retina of the eye (34), deriving a geometrical remapping which converts the two dimensional representation of the retinal portion to a three dimensional representation of the retinal portion (36), using one or more coordinates of the two dimensional representation of the retinal portion to define the geometrical measurement to be taken of the retina on the two dimensional representation (38), using the geometrical remapping to convert the or each coordinate of the two dimensional representation of the retinal portion to an equivalent coordinate of the three dimensional representation of the retinal portion (40), and using the or each equivalent coordinate of the three dimensional representation of the retinal portion to determine the geometrical measurement of the retina of the eye (42).

Abstract: A method of determining a measurement of at least one cell type in an eye, comprising (i) obtaining a map of the cell type in the eye, (ii) obtaining a representation of the retina of the eye, (iii) matching the eye cell type map to the representation of the retina of the eye, (iv) defining a region of interest on the representation of the retina of the eye, (v) calculating a size of the region of interest on the representation of the retina of the eye, (vi) using the matched eye cell type map and the size of the region of interest to determine a measure of the cell type in the region of interest of the retina of the eye.

Abstract: Apparatus for illuminating the retina of an eye. The apparatus includes an illumination device and a lens system. The illumination device and the lens system combine to provide incident illumination from an apparent point source located within the lens system. The apparatus also includes an illumination transfer device. The illumination transfer device has two foci and the apparent point source of the lens system is provided at a first focus point of the illumination transfer device and an eye is accommodated at a second focus point of the illumination transfer device. The illumination transfer device transfers the incident illumination from the apparent point source into the eye to illuminate the retina.

Abstract: An ophthalmoscope (10) comprising a light source (12), a first scanner (14), a first scan transfer element (16), a second scanner (18), and a second scan transfer element (20), which provide a two-dimensional scan of incident light from an apparent point source at a pupillary point of an eye (22) onto the fundus of the eye, and which descan a two-dimensional scan of return light from the fundus of the eye to provide return light from an apparent point source at the first scanner, wherein the first scan transfer element comprises a free-form element which has a shape defined to provide aberration correction of the return light from the fundus of the eye.

Abstract: A laser scanning system adapted to produce a scanned image including a number of lines of an object. A method includes the steps of providing a reference object arranged such that the scanned image produced by the laser scanning system includes a reference image of the reference object, processing the reference image to calculate an error arising from non-repeatable displacement of the lines of the reference image, and adjusting at least one operating parameter of the laser scanning system in response to the calculated error.

Abstract: A scanning laser ophthalmoscope for scanning the retina of an eye is provided comprising a light source emitting a beam of light, scan relay elements, wherein the light source and the scan relay elements provide a two-dimensional scan of the light beam which is transferred from an apparent point source at a pupillary point of the eye to the retina of the eye, and a static aberration correction element which has a shape defined to provide correction of aberrations of at least some of the scan relay elements and a location within the ophthalmoscope chosen to provide correction of aberrations of at least some of the scan relay elements, which location maintains transfer of the beam of light from the apparent point source at the pupillary point of the eye to the retina of the eye.

Abstract: The disclosure relates to a non-transitory computer-readable storage medium storing computer program instructions which, when executed by a processor, cause the processor to process image data defining an image of a retina to determine a location of an anatomical feature of the retina in the image by receiving the image data; calculating, for each of a plurality of pixels of the image data, a respective local orientation vector indicative of the orientation of any blood vessel present in the image; calculating a normalized local orientation vector for each of the plurality of pixels; operating on an array of accumulators, wherein each accumulator in the array is associated with a respective pixel of the image data; and determining the location of the anatomical feature in the image of the retina using the location of a pixel of the image data which is associated with an accumulator having accumulated an accumulated value.

Abstract: The present disclosure relates to a computer-readable storage medium storing instructions that can cause a processor to process image data defining an image of a vascular structure of temporal vascular arcades of a retina to estimate a location of the fovea of the retina in the image by transforming received image data such that the vascular structure in the image defined by the transformed image data is more circular than the vascular structure defined by the image data; calculating, for each of a plurality of pixels of the transformed image data, a respective local orientation vector indicative of the orientation of any blood vessel present in the image; calculating a normalized local orientation vector for each of the pixels; operating on an array of accumulators; and estimating the location of the fovea in the image of the retina using the location of a pixel of the transformed image data.

Abstract: Apparatus for illuminating the retina of an eye. The apparatus includes an illumination device and a lens system. The illumination device and the lens system combine to provide incident illumination from an apparent point source located within the lens system. The apparatus also includes an illumination transfer device. The illumination transfer device has two foci and the apparent point source of the lens system is provided at a first focus point of the illumination transfer device and an eye is accommodated at a second focus point of the illumination transfer device. The illumination transfer device transfers the incident illumination from the apparent point source into the eye to illuminate the retina.

Abstract: A scanning laser ophthalmoscope (SLO) for imaging the retina of an eye comprises a source (12) of collimated light, a scanning device (14, 16, 1328, 1319), a scan transfer device (20) and a detector (1310). The scan transfer device has a first focus (16) at which an apparent point source is provided and a second focus (24) at which an eye (524, 1324) may be accommodated. The scan transfer device transfers a two-dimensional collimated light scan from the apparent point source into the eye. An optical coherence tomography (OCT) system (900) is combined with the SLO, the OCT system providing OCT reference and sample beams. The OCT sample beam (902) propagates along the same optical path as of the SLO collimated light through the scan transfer device. An aberration compensator (1204, 1316) automatically compensates for systematic aberrations and/or changes in wavefront introduced by scanning elements and the scan transfer device as a function of scan angle.

Abstract: The invention provides an apparatus and method for illuminating, imaging and treating the retina of an eye. The apparatus (10) comprises an illuminating device (16) including a planar light source capable of producing light in a plane, such that the illuminating device (16) is capable of illuminating a circumferential line on the retina (12) and a support structure, wherein the illuminating device (16) is pivotably mountable to the support structure and is rotatable about an axis (18) which lies substantially on the plane defined by the light source, such that, in use, the illuminating device (16) may be rotated about the axis (18) to illuminate an area of the retina (12).

Abstract: A method of reducing jitter error in a laser scanning system adapted to produce a scanned image including a number of lines of an object. The method includes the steps of providing a reference object arranged such that the scanned image produced by the laser scanning system includes a reference image of the reference object, processing the reference image to calculate an error arising from non-repeatable displacement of the lines of the reference image, and adjusting at least one operating parameter of the laser scanning system in response to the calculated error.

Abstract: An ophthalmoscope (10) comprising a light source (12), a first scanner (14), a first scan transfer element (16), a second scanner (18), and a second scan transfer element (20), which provide a two-dimensional scan of incident light from an apparent point source at a pupillary point of an eye (22) onto the fundus of the eye, and which descan a two-dimensional scan of return light from the fundus of the eye to provide return light from an apparent point source at the first scanner, wherein the first scan transfer element comprises a free-form element which has a shape defined to provide aberration correction of the return light from the fundus of the eye.