Eye examination device and eye examination method

Abstract

An eye examination device that combines an objective optical examination subsystem and a subjective optical examination subsystem, wherein the subjective examination is based on retinal scanning display technology and includes optical elements that are used in common with the optical system for the objective examination. Potentially, it supports performing both objective and subjective rapid visual acuity examinations and / or refractive error examinations in a compact, simple, and potentially cost-effective system. The examination results can provide a basis suitable for eyeglass and / or contact lens prescriptions.

Description

Technical Field

[0001] Related Applications This application claims the priority of U.S. Provisional Patent Application No. 63 / 347,719, filed on June 1, 2022, under 35 USC § 119(e), the entire content of which is hereby incorporated by reference into this specification.

Background Art

[0002] Some embodiments of the present invention relate to the field of visual inspection, and more particularly to vision testing.

[0003] Vision testing typically consists of an objective refractive error test followed by a subjective vision test. Devices of the objective refractive error test type are generally auto refractors or the like. Devices of the subjective vision test type are most often phoropters for the subject to view a vision chart (Snellen, Landolt ring, tumbling E). The vision chart is usually placed at an apparent distance of about 6 meters for distant vision testing or about 0.4 meters for near vision testing.

[0004] The background art includes U.S. Patent No. 4,465,348, U.S. Patent Application No. 2020 / 0077885, and U.S. Patent Application No. 2020 / 0275833.

Summary of the Invention

[0005] According to one aspect of some embodiments of the present invention, an eye examination apparatus operates to perform both a subjective visual acuity examination and an objective visual acuity examination including projecting an image and an examination pattern onto at least a first retina of a subject during the examination, the eye examination apparatus comprising: a first optical path having a retinal scanning display that projects a subjective visual acuity examination image onto the first retina; and a second optical path configured to project an objective visual acuity examination pattern onto the first retina and including a sensor that detects light returning from the first retina based on the objective visual acuity examination pattern, wherein the retinal scanning display projects a target image onto the first retina as a target for visual fixation and / or relaxation of accommodation by the subject during the operation of projecting the objective visual acuity examination pattern of the second optical path.

[0006] According to some embodiments of the present invention, the eye examination apparatus includes an optical system in the first optical path that is adjusted to introduce a variable optical refractive power to a first image beam irradiated onto the first retina to generate a subjective visual acuity examination image.

[0007] According to some embodiments of the present invention, the optical system includes at least one spherical correction element that is adjusted to introduce a variable spherical optical refractive power to the first image beam.

[0008] According to some embodiments of the present invention, the optical system includes at least one cylindrical correction lens that is adjusted to introduce a variable cylindrical optical refractive power and a variable cylindrical optical axis to the first image beam.

[0009] According to some embodiments of the present invention, the cylindrical correction lens includes at least one of a liquid lens and a liquid crystal lens.

[0010] According to some embodiments of the present invention, at least one cylindrical correction lens comprises a first cylindrical correction lens group and a second cylindrical correction lens group, each group having at least one cylindrical lens, the first cylindrical correction lens group and the second cylindrical correction lens group having cylindrical optical refractive powers of opposite signs, and being adjusted together to introduce a variable cylindrical axis while maintaining the alignment of the respective cylindrical axes of the first cylindrical correction lens group and the second cylindrical correction lens group with respect to each other, and being adjusted to introduce a variable cylindrical optical refractive power by varying the relative distance between the first cylindrical correction lens group and the second cylindrical correction lens group.

[0011] According to some embodiments of the present invention, the alignment of the respective cylindrical axes with respect to each other is directed within 5° of each other.

[0012] According to some embodiments of the present invention, an eye examination device comprises a first optical path, a second optical path, and a first projection system for a first retina comprising a retinal scanning display, and a second projection system for a second retina of a subject, the second projection system having features corresponding to each feature listed for the first projection system, and the first projection system and the second projection system cooperate to provide respective images arranged as binocularly aligned images to the first retina and the second retina.

[0013] According to some embodiments of the present invention, an eye examination device comprises one or more mechanical degree-of-freedom stages for positioning the optical pupils of the first projection system and the second projection system in a relative position that accommodates the range of the eye placement geometry of a human subject, and at least one sensor configured to detect the binocular alignment state between the optical pupil and the subject's eye, at least during the preparation of the subject for the examination.

[0014] According to some embodiments of the present invention, an eye examination apparatus includes one or more actuators that move one or more stages, and a controller having a processor configured to operate the one or more actuators according to the detected binocular alignment state to align an optical pupil with the eye of a subject.

[0015] According to some embodiments of the present invention, at least one of the first projection system and the second projection system includes a moving element that adjusts the relative viewing angle of the respective first optical path.

[0016] According to some embodiments of the present invention, the moving element is operable to adjust the relative angle during the presentation of at least one of the subjective visual acuity test image and the target image.

[0017] According to some embodiments of the present invention, the operation of the moving element simultaneously adjusts the relative viewing angles of the first optical path and the second optical path.

[0018] According to some embodiments of the present invention, the eye examination apparatus includes, for each of the first projection system and the second projection system, a third optical path configured to merge the field of view of the subject's surrounding environment with the images and test patterns of the first optical path and the second optical path.

[0019] According to some embodiments of the present invention, the eye examination apparatus includes at least one eye tracking device configured to track at least one of the state and position of the eye during at least one of a subjective visual acuity test and an objective visual acuity test.

[0020] According to some embodiments of the present invention, the subjective visual acuity test image includes at least one of the group consisting of a Snellen chart, a Landolt ring chart, a tumbling E chart, a Lea test, an HDTV chart, a Sumbers chart, a clock dial chart, and a spatial frequency chart.

[0021] According to some embodiments of the present invention, a subjective visual acuity test image is presented for binocular vision with a depth cue that positions at least two portions of the subjective visual acuity test image at different apparent distances from the subject.

[0022] According to some embodiments of the present invention, an objective visual acuity test pattern includes a plurality of beams selected to indicate refractive errors by making different incidences on the retina for different refractive errors of the eye's optical system that focuses light on the retina according to the Scheiner principle.

[0023] According to some embodiments of the present invention, an eye examination device includes a processor configured to receive data from a sensor and determine a refractive error of the eye's optical system based on at least one of the group consisting of Shack-Hartmann wavefront sensing, knife-edge effect, ray tracing aberration measurement, image size principle, and / or Scheiner principle.

[0024] According to some embodiments of the present invention, an objective visual acuity test pattern includes a pattern of beams sequentially projected onto the retina, and the eye examination device includes a processor configured to receive data from a sensor and determine a wavefront error according to a correlation between the direction of the pattern of beams incident on the eye and the retroreflection of the pattern detected by the sensor after exiting the eye.

[0025] According to some embodiments of the present invention, the retinal scanning display of the first optical path includes a MEMS mirror, and the MEMS mirror is also used for generating an objective visual acuity test pattern.

[0026] According to some embodiments of the present invention, the retinal scanning display of the first optical path includes a plurality of MEMS mirrors that operate to scan one or more beams along different axes.

[0027] According to some embodiments of the present invention, the eye examination device includes a keratometer.

[0028] According to some embodiments of the present invention, the target image includes at least one blurred region and a moving object that moves in apparent depth.

[0029] According to one aspect of some embodiments of the present invention, aligning an ophthalmic device with respect to an eye of a subject, and while the ophthalmic device is aligned with respect to the eye of the subject, using a retinal scanning display of the ophthalmic device to project a subjective visual acuity test image onto a first retina, using an illumination source of the ophthalmic device to project an objective visual acuity test pattern onto the first retina, using a light sensor of the ophthalmic device to detect light returning from the first retina based on the objective visual acuity test pattern, and using the retinal scanning display to project a target image onto the first retina as a target for visual fixation and / or relaxation of accommodation by the subject during projection and detection of the objective visual acuity test pattern. An eye examination method is provided.

[0030] According to some embodiments of the present invention, the method further includes adjusting an optical correction power used to project a subjective visual acuity test image onto the first retina based on an input from the subject.

[0031] According to some embodiments of the present invention, the subjective visual acuity test image is presented for binocular vision, and the input from the subject includes an indication of the relative appearance in the two eyes of the image presented for binocular vision.

[0032] According to some embodiments of the present invention, the method includes projecting the target image onto the first retina via an optical system that is adjusted while projecting the subjective visual acuity test image onto the first retina.

[0033] According to some embodiments of the present invention, the method performs each operation performed on the first retina on the second retina of the subject as well, and while the ophthalmic device is aligned with respect to the eye of the subject.

[0034] According to some embodiments of the present invention, at least one of the subjective vision test image and the target image is presented for binocular vision of the subject.

[0035] According to some embodiments of the present invention, the method includes adjusting the vergence of the subject's eyes by adjusting the apparent depth of at least one image presented for binocular vision.

[0036] According to some embodiments of the present invention, the method adjusts the accommodation of the subject's crystalline lens by adjusting the apparent depth of at least one image presented for binocular vision.

[0037] According to some embodiments of the present invention, an optical path is provided that is configured to project an image onto the retina of an eye and includes a cylindrical lens that introduces a variable cylindrical optical refractive power and a variable cylindrical optical axis into the beam incident on the retina to generate an image. The cylindrical lens has a first cylindrical correction lens group and a second cylindrical correction lens group each including at least one cylindrical lens. The first cylindrical correction lens group and the second cylindrical correction lens group have cylindrical optical refractive powers of opposite signs and are adjusted together to introduce a variable cylindrical axis while maintaining a predetermined relative alignment of the cylindrical axes of the first cylindrical correction lens group and the second cylindrical correction lens group. An image display device is provided that is adjusted by changing the distance between them to introduce a variable cylindrical optical refractive power.

[0038] According to some embodiments of the present invention, at least the second cylindrical correction lens group includes a plurality of cylindrical lenses, and the cylindrical optical refractive powers of the plurality of cylindrical lenses are combined along the optical path to generate a cylindrical optical refractive power of the opposite sign to that of the first cylindrical correction lens group.

[0039] According to some embodiments of the present invention, the second cylindrical correction lens group has at least one lens on either side of at least one lens of the first cylindrical correction lens group.

[0040] According to some embodiments of the present invention, at least one lens of the second cylindrical correction lens group moves along the optical path to change the introduced cylindrical optical refractive power, and there is at least one position of at least one lens of the second cylindrical correction lens group that cancels the cylindrical optical refractive power of the first cylindrical correction lens group.

[0041] According to some embodiments of the present invention, the first cylindrical correction lens group and the second cylindrical correction lens group are located within the telecentric region of the beam.

[0042] According to some embodiments of the present invention, the beam has an overall envelope diameter and individually forms an image at a focal position on the retina, and the envelope diameter of the beam is substantially constant between the first cylindrical correction lens group and the second cylindrical correction lens group.

[0043] According to some embodiments of the present invention, each individual beam has a beam waist within a region defined between the lenses of the first cylindrical correction lens group and the second cylindrical correction lens group.

[0044] According to some embodiments of the present invention, the first cylindrical correction lens group and the second cylindrical correction lens group change the cylindrical correction power in a range of at least 2 diopters by adjusting the distance between them.

[0045] According to some embodiments of the present invention, the first cylindrical correction lens group and the second cylindrical correction lens group rotate together about the optical axis of the optical path to introduce a variable cylindrical axis.

[0046] According to some embodiments of the present invention, the image display device forms an optical pupil that is an optical pupil for the eye and has a first diameter in a direction that is most affected by the variable cylindrical optical refractive power and a second diameter orthogonal to the first diameter, and the ratio of the first diameter to the second diameter is maintained less than 2 over an adjustment range of at least 4 diopters.

[0047] According to some embodiments of the present invention, an image display device includes display illumination for generating an image, and the display illumination includes at least one of the group consisting of a μLED display, a μOLED display, an LED display, an OLED display, a QDLED display, an LCD display, an LCOS source, a DLP source, and a scanning beam source.

[0048] According to one aspect of some embodiments of the present invention, a method of changing the cylindrical aberration introduced into an image forming light beam, the method including moving a first cylindrical lens from a first position to a second position along the optical axis of the image forming light beam, moving the first cylindrical lens changing the distance to a second cylindrical lens, each of the first cylindrical lens and the second cylindrical lens having a cylindrical axis, the cylindrical axes being aligned with each other, the image forming light beam forming an optical pupil having a first diameter in a direction most affected by the movement of the first cylindrical lens and a second diameter orthogonal to the first diameter at a location ahead of the first cylindrical lens and the second cylindrical lens, and maintaining the ratio of the first diameter to the second diameter less than 2 over a range of cylindrical aberration of at least 4 diopters introduced into the image forming light beam.

[0049] According to some embodiments of the present invention, at at least one position of the first cylindrical lens during movement, the cylindrical refractive power introduced into the beam after passing through the first cylindrical lens and the second cylindrical lens is substantially zero.

[0050] According to some embodiments of the present invention, the second diameter is less than 5 mm.

[0051] According to one aspect of some embodiments of the present invention, there is provided an eye examination apparatus including: a first optical path configured to project a subjective visual acuity test image onto a retina of a subject; a second optical path configured to project an objective visual acuity test pattern onto the retina of the subject and including a sensor configured to sense light returning from the retina based on the objective visual acuity test pattern; and a third optical path configured to merge a field of view of the surrounding environment of the subject with an image and a test pattern of either the first optical path or the second optical path. The first optical path projects a target image onto the retina as a target for fixation of vision and / or relaxation of accommodation by the subject while the second optical path operates to project the objective visual acuity test pattern.

[0052] According to some embodiments of the present invention, the eye examination apparatus includes, in the first optical path, an optical system that is adjusted to introduce a variable optical refractive power to a first image beam that irradiates a first retina to generate a subjective visual acuity test image.

[0053] According to some embodiments of the present invention, the optical system includes at least one spherical correction element that is adjusted to introduce a variable spherical optical refractive power to the first image beam.

[0054] According to some embodiments of the present invention, the optical system includes at least one cylindrical correction lens that is adjusted to introduce a variable cylindrical optical refractive power and a variable cylindrical optical axis to the first image beam.

[0055] According to some embodiments of the present invention, the cylindrical correction lens includes at least one of a liquid lens and a liquid crystal lens.

[0056] According to some embodiments of the present invention, at least one cylindrical correction lens comprises a first cylindrical correction lens group and a second cylindrical correction lens group, each group having at least one cylindrical lens, the first cylindrical correction lens group and the second cylindrical correction lens group having cylindrical optical refractive powers of opposite signs, and being adjusted together to introduce a variable cylindrical axis while maintaining the alignment of the respective cylindrical axes of the first cylindrical correction lens group and the second cylindrical correction lens group with respect to each other, and being adjusted to introduce a variable cylindrical optical refractive power by changing the relative distance between the first cylindrical correction lens group and the second cylindrical correction lens group.

[0057] According to some embodiments of the present invention, the alignment of the respective cylindrical axes with respect to each other is oriented within 5° of each other.

[0058] According to some embodiments of the present invention, an eye examination device comprises a first projection system for a first retina, comprising a first optical path, a second optical path, and a third optical path, and a second projection system for a second retina of a subject, the second projection system having features corresponding to each of the features listed for the first projection system, the first projection system and the second projection system cooperating to provide respective images arranged as binocularly aligned images to the first retina and the second retina.

[0059] According to some embodiments of the present invention, an eye examination device comprises one or more mechanical degree-of-freedom stages for positioning the optical pupils of the first projection system and the second projection system in relative positions that accommodate the range of the eye placement geometry of a human subject, and at least one sensor configured to detect the state of binocular alignment between the optical pupils and the eyes of the subject, at least during preparation for the examination of the subject.

[0060] According to some embodiments of the present invention, an eye examination apparatus includes one or more actuators that move one or more stages, and a controller having a processor configured to operate the one or more actuators in accordance with the detected binocular alignment state to align the optical pupil with the eye of a subject.

[0061] According to some embodiments of the present invention, at least one of the first projection system and the second projection system includes a moving element that adjusts the relative viewing angle of the respective first optical path.

[0062] According to some embodiments of the present invention, the moving element is operable to adjust the relative angle during the presentation of at least one of the subjective visual acuity test image and the target image.

[0063] According to some embodiments of the present invention, the operation of the moving element simultaneously adjusts the relative viewing angles of the first optical path and the second optical path.

[0064] According to some embodiments of the present invention, an eye examination apparatus includes at least one eye tracking device configured to track at least one of the state and position of an eye during one or both of a subjective visual acuity test and an objective visual acuity test.

[0065] According to some embodiments of the present invention, the subjective visual acuity test image includes at least one of the group consisting of a Snellen chart, a Landolt ring chart, a tumbling E chart, a Lea test, an HDTV chart, a Sanburst chart, a clock dial chart, and a spatial frequency chart.

[0066] According to some embodiments of the present invention, the subjective visual acuity test image is presented for binocular vision with a depth cue that positions at least two portions of the subjective visual acuity test image at different apparent distances from the subject.

[0067] According to some embodiments of the present invention, the objective vision test pattern includes a plurality of beams selected such that, according to the Scheiner principle, different incidences on the retina are made for different refractive errors of the eye's optical system that focuses light on the retina, thereby indicating the refractive error.

[0068] According to some embodiments of the present invention, the eye examination device includes a processor configured to receive data from a sensor and determine a refractive error of the eye's optical system based on at least one of the group consisting of Shack-Hartmann wavefront sensing, knife-edge effect, ray tracing aberration measurement, image size principle, and / or Scheiner principle.

[0069] According to some embodiments of the present invention, the objective vision test pattern includes a predetermined pattern of beams sequentially projected onto the retina, and the eye examination device includes a processor configured to receive data from a sensor and determine a wavefront error according to the correlation between the direction of the beams of the predetermined pattern incident on the eye and the retroreflection of the pattern detected by the sensor after exiting the eye.

[0070] According to some embodiments of the present invention, the eye examination device includes a keratometer.

[0071] According to some embodiments of the present invention, the target image includes at least one of a blurred region and a moving element that moves in apparent depth.

[0072] According to some embodiments of the present invention, the eye examination device includes display illumination for generating an image, and the display illumination includes at least one of the group consisting of a μLED display, a μOLED display, an LED display, an OLED display, a QDLED display, an LCD display, an LCOS source, a DLP source, and a scanning beam source.

[0073] According to one aspect of some embodiments of the present invention, a method of performing a vision test, comprising: providing a refraction vision test device accessible to a subject in a part of an open retail space defined by one or more display cabinets and a countertop, or providing the refraction vision test device in a space bounded by at least one of the countertop and one or more display cabinets or a combination thereof; operating the refraction vision test device to perform both a subjective vision test and an objective vision test while the subject remains aligned with the refraction vision test device; and providing a lens prescription to the subject based on the results of the subjective vision test and the objective vision test.

[0074] According to some embodiments of the present invention, the method includes recording an order from the subject for a vision correction optical system including at least one item for sale selected according to an item displayed in one or more display cabinets.

[0075] Unless otherwise defined, all technical and / or scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. Although methods and materials similar or equivalent to those described herein can be used in the practice or testing of embodiments of the present disclosure, exemplary methods and / or materials are described below. In case of conflict, the patent specification, including definitions, will control. In addition, the materials, methods, and examples are illustrative only and not intended to be limiting.

[0076] As will be understood by those skilled in the art, aspects of the present disclosure may be embodied as a system, method, or computer program product. Accordingly, aspects of the present disclosure may take the form of an entirely hardware embodiment, an entirely software embodiment (including firmware, resident software, microcode, etc.), or an embodiment combining software aspects and hardware aspects, all of which may generally be referred to herein as a "circuit," "module," or "system" (e.g., a method may be implemented using a "computer circuit"). Additionally, some embodiments of the present disclosure may take the form of a computer program product embodied in one or more computer-readable media having computer-readable program code thereon.

[0077] The execution of the methods or systems of some embodiments of the present disclosure may include performing and completing selected tasks manually, automatically, or a combination thereof.

[0078] Furthermore, according to some embodiments of the actual measurement devices and apparatuses of the methods and / or systems of the present disclosure, some selected tasks may be implemented by hardware, software, firmware, and / or combinations thereof (e.g., using an operating system).

[0079] For example, the hardware for performing tasks selected according to some embodiments of the present disclosure may be implemented as a chip or a circuit. As software, the tasks selected according to some embodiments of the present disclosure may be implemented as a plurality of software instructions executed by a computer using any suitable operating system. In some embodiments of the present disclosure, one or more tasks executed in a method and a system are executed by a data processor (when referring to a data processor that operates using a group of digital bits, also referred to as a "digital processor"), such as a computing platform for executing a plurality of instructions. The instruction execution element of the processor may include, for example, one or more microprocessor chips, ASICs, and / or FPGAs. Optionally, the data processor includes a volatile memory for storing instructions and / or data, and / or a non-volatile storage device such as a magnetic hard disk and / or removable media for storing instructions and / or data. Optionally, a network connection is also provided. A display device and user input devices such as a keyboard and a mouse are also provided as options. Any of these embodiments is more generally referred to as an instance of a computer circuit.

[0080] In some embodiments, any combination of one or more computer-readable media may be utilized. The computer-readable media may be a computer-readable signal medium or a computer-readable storage medium. The computer-readable storage medium may be, for example, any system, apparatus, or device of an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, or a suitable combination thereof. More specific examples (non-exhaustive list) of the computer-readable storage medium include an electrical connection having one or more wirings, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or a suitable combination thereof. As used herein, the computer-readable storage medium can be any tangible medium that can contain or store a program used by or in connection with an instruction execution system, apparatus, or device. The computer-readable storage medium can also contain information for use in such a program, such as data structured in a manner recorded by the computer-readable storage medium, and the computer program can access the data as, for example, one or more tables, lists, arrays, data trees, and / or other data structures.

[0081] Here, a computer-readable storage medium that records data as a group of digital bits is also referred to as a digital memory. In some embodiments, it should be understood that if the computer-readable storage medium is not essentially read-only and / or is in a read-only state, the computer-readable storage medium may optionally also be used as a computer-writable storage medium.

[0082] Here, the data processor is "configured" to perform data processing actions as long as it is connected to a computer-readable medium, receives instructions and / or data therefrom, processes them, and / or stores the processing results in the same or another computer-readable medium. The processing (processing optionally performed on data) is defined by instructions, and the processing is performed by the processor operating in accordance with the instructions. The act of processing may additionally or alternatively be referred to by one or more other terms (e.g., comparing, estimating, determining, calculating, identifying, associating, storing, analyzing, selecting, and / or transforming). For example, in some embodiments, a digital processor receives instructions and data from a digital memory, processes the data in accordance with the instructions, or stores the processing results in the digital memory. In some embodiments, "providing" the processing results includes transmitting, storing, or presenting one or more of the processing results. Presentation may optionally include displaying on a display device, indicating audibly, printing in a printed matter, or otherwise providing the results in a form accessible to human sensory capabilities.

[0083] A computer-readable signal medium may include, for example, a propagated data signal in which computer-readable program code is embodied, either baseband or as part of a carrier wave. The signal so propagated can take any of a variety of forms, including electromagnetic forms, optical forms, or any suitable combination thereof. A computer-readable signal medium can be any computer-readable medium that can communicate, propagate, or transport a program for use by or in connection with an instruction execution system, an instruction execution apparatus, or an instruction execution device that is not a computer-readable storage medium.

[0084] The program code and / or data embodied in the computer-readable medium may be transmitted using any appropriate medium, such as wireless, wire, optical fiber cable, RF, or the like, or any suitable combination thereof.

[0085] Computer program code for performing the operations for some embodiments of the present disclosure may be written in any combination of one or more programming languages including object-oriented programming languages such as Java, Smalltalk, C++, and conventional procedural programming languages such as the "C" programming language or similar programming languages. Additionally or alternatively, sequences of logical operations (optionally, logical operations corresponding to computer instructions) may be embedded in the design of an ASIC and / or the configuration of an FPGA device. The program code may be executed entirely on the user's computer as a stand-alone software package, may be executed partially on the user's computer, may be executed partially on the user's computer and partially or entirely on a remote computer or server. In the latter scenario, the remote computer may be connected to the user's computer via any type of network including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0086] Some embodiments of the present disclosure may be described below with reference to the flowcharts and / or block diagrams of methods, apparatuses (systems), and computer program products according to embodiments of the present disclosure. It should be understood that each block of the flowchart and / or each block of the block diagram, and combinations of blocks in the flowchart and / or block diagram, can be implemented by instructions of a computer program. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing apparatus to form means for realizing the functions / operations specified in the flowchart and / or block diagram or block, and can be executed as instructions executed via the processor of the computer or other programmable data processing apparatus.

[0087] These computer program instructions may also be stored in a computer-readable medium that can direct a computer, other programmable data processing apparatus, or other devices to perform specific operations, and by the instructions stored in the computer-readable medium, a product can be produced that includes instructions for performing the specific functions / operations of the flowchart and / or block diagram.

[0088] The computer program instructions may be loaded into a computer, other programmable data processing apparatus, or other devices and cause a series of operational steps to be performed in the computer, other programmable apparatus, or other devices, thereby generating a computer-implemented process. As a result, the instructions executed on the computer or other programmable apparatus provide a process for implementing the specific functions / operations of the flowchart and / or block diagram.

[0089] Some of the methods described herein are generally intended for computer use only and may not be feasible or practical to perform purely manually by a human expert. A human expert who wishes to manually perform a similar task such as inspecting an object is expected to use a completely different method, for example, by utilizing expertise and / or the pattern recognition ability of the human brain. This can be far more efficient than manually proceeding with the steps of the method herein.

[0090] For some embodiments of the present disclosure, they will be described herein with reference to the accompanying drawings for illustrative purposes only. Here, by referring to the drawings in detail, it is emphasized that a specific part of the figure is an example and is for the purpose of an exemplary discussion of the embodiments of the present disclosure. Similarly, by looking at the description together with the drawings, it will be clear to those skilled in the art how the embodiments of the present disclosure can be practiced.

Brief Description of the Drawings

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DETAILED DESCRIPTION OF THE INVENTION

[0092] Some embodiments of the present invention relate to the field of vision inspection, and more particularly to vision testing.

[0093] ·Overview Broad aspects of some embodiments of the present disclosure relate to vision inspection systems and / or methods configured to accommodate both objective and subjective measurements of eye refraction (an important factor in vision), for example, for determining corrective lens prescriptions for glasses and / or contact lenses. In some embodiments, the measurement and / or determination of the associated corrective lens prescription includes the determination of refractive error (quantification of eye refraction) and / or visual acuity (which indicates the spatial resolution of the entire visual processing system, is determined subjectively, and is affected by eye refraction).

[0094] In some embodiments, the objective inspection optical subsystem includes at least one beam source and an optical system that directs light from the at least one beam source towards the eye of the subject along one or more optical paths. In some embodiments, the optical path includes a scanning mirror (e.g., a microelectromechanical system (MEMS) scanning mirror) configured to direct incident light from the at least one beam source to different positions (e.g., by adjusting the angle of the mirror). This is used, for example, to generate an optical pattern suitable for inspection that is projected onto the eye of the subject. In some embodiments, the mirror operates at a scanning speed that generates a frame rate greater than 30 Hz, preferably greater than 50 Hz. The resolution is preferably suitable for generating an image with a pixel resolution of, for example, 800×600, 1280×720, or higher. After the optical system is added, this can be used to generate an image with a resolution of at least about 1 minute of arc, 0.5 minute of arc, or 0.3 minute of arc (e.g., a resolution sufficient to detect a decrease in human eye vision within the normal tolerance of a vision test). Optionally, the angular size of the image is, for example, approximately ±5° (e.g., at least ±3°) in the horizontal direction and approximately ±3° (e.g., at least ±2°) in the vertical direction.

[0095] In some embodiments, light from a first beam source reflected from the surface of an eye is directed to and analyzed by a sensor. The detected reflected light has refractive information that is used in an analysis to estimate the objective refraction of the subject's eye. The light emitted from the first beam source may be near-infrared (IR), for example, having a wavelength greater than 640 nm. Optionally or additionally, light of other wavelengths is used.

[0096] During an objective vision test, the subject focuses on a target. The target optically has a blurred region, for example, a blurred background region, and optically has an element that moves at an apparent depth, for example, an element that moves away from the viewing subject. In some embodiments, the scanning mirror is also used to create a target on which the subject focuses, for example, a target formed by light emitted from a second beam source. In some embodiments, the second beam source, scanning mirror, and optical path used to create the target in the objective vision test are also used in the subjective vision test to present a vision test chart and / or other image.

[0097] In some embodiments, the subjective examination optical subsystem is configured to subjectively determine the refraction of the subject's eye based on the subject's report of the appearance of a test image generated by a projection unit. In some embodiments, the image is projected onto the subject's retina by two-dimensionally scanning one or more laser beams from a beam source (e.g., a second beam source). The scanning is performed, for example, by adjusting the angle of the scanning mirror. Optionally, the same mirror is used in both the subjective and objective examinations.

[0098] In some embodiments, the subjective examination optical subsystem includes a defocus assembly unit that acts as a phoropter of the device to apply an adjustable corrective refractive power that includes at least spherical correction applied to the image seen by the subject. The defocus unit is adjustable to produce a gradual and / or continuous change in the divergence or convergence of the laser beam. Using the subject's feedback, the refractive power that best corrects the subject's vision is determined.

[0099] The subjective examination optical subsystem optionally has a cylindrical and axial optical correction assembly. This introduces an adjustable distortion into the shape of the scanning laser beam. During the vision examination, the adjustment is selected to correct the subject's eye's cylindrical and axial errors. For example, it is adjusted based on the subject's feedback on how clearly the target appears, or which target can be seen or identified. In some embodiments, the subsystem includes an optical relay configured to provide an appropriate magnification and to align the exit pupil of the optical subsystem with the subject's eye. When presenting a focus target presented with the objective vision examination using a second beam source, the defocus assembly unit and the cylindrical and axial optical correction assembly optical subsystem may be present in the optical path or removed from the optical path. If present, they are optionally adjusted to a neutral setting (e.g., a neutral position) or to a position known and / or estimated to fully or partially correct the refractive error of the subject's eye.

[0100] In some embodiments, the starting point for the shape setting of the scanned beam in the subjective vision test is based on available data indicating the refractive error of the subject. The data includes, for example, the subject's previous prescription, measurements of currently used prescription lenses, and / or other available information related to the subject's vision and eye medical history. Additionally or alternatively, the initial setting is based on data obtained from an objective vision test, for example, a test performed using an objective test optical subsystem. The objective test optical subsystem optionally utilizes effects, principles, sensors, and / or methods related to appropriate objective lens characteristics. Examples include Shack-Hartmann wavefront sensing, knife-edge effect, image size principle, ray tracing aberrometry, or Scheiner principle, among others.

[0101] The initial setting is optionally set exactly according to the best available data or offset from the best available data using, for example, added or subtracted coefficients. For example, a positive or negative offset of about 2 to 4 diopters (e.g., 2, 3, or 4 diopters) is applied to reduce accommodation. Based on feedback from the subject, the sphere, cylinder, and axis are adjusted and combined corrections are adjusted until they generate the best visible image on the subject's retina. Subjective sphere, cylinder, and axis errors are determined from parameters characterizing the changes (e.g., divergence, convergence, astigmatism, cylinder axis) of the scanned beam such that an optimized image is formed on the subject's retina, providing information regarding the prescription of glasses or contact lenses. This may be provided in combination with additional information such as corneal curvature.

[0102] Optionally, one or both of the objective inspection optical subsystem and the subjective inspection optical subsystem are replicated (e.g., copied at least in their main optical characteristics, optionally with packaging adjustments such as mirroring of component placement), and both eyes can be inspected simultaneously or alternately without adjusting the position of the system. Preferably, the images generated by the replicated system are aligned for binocular vision to generate a perceptually unified image for the subject (assuming that the subject has depth perception within the range of physical settings available in the device). Thereby, a sense of depth can be generated in the image. Optionally, the binocularly aligned images include, for example, depth cues and differences between the images, or are feature differences used in the inspection.

[0103] Optionally, one or both of the objective inspection optical subsystem and the subjective inspection optical subsystem can be switched to either eye alternately (e.g., using a mirror), or can be viewed simultaneously by both eyes (e.g., using a prism and / or a beam splitter). For example, in some embodiments, the objective vision inspection is performed at least partially simultaneously with the subjective vision inspection. For example, the objective vision inspection can incidentally use the vision inspection target of the subjective vision inspection as an attention-arousing stimulus to help set the accommodation of the subject's lens. Particularly emphasized with respect to this parallelism is that the objective vision inspection can use IR (invisible) wavelengths for the inspection itself and, optionally, can share the same display used during the subjective vision inspection for target presentation.

[0104] Optionally, using the intermediate results of one inspection modality to adjust the inspection of the other modality and, optionally, iteratively adjust. For example, using objective visual inspection, an initial range of the subjective visual inspection correction power to be inspected can be set, and then, using the results of the subjective inspection, the presentation of visual stimuli that can be used to set the subject's near and far accommodation for further objective vision inspection can be adjusted, or the range of inspection parameters for which further objective inspection is intensively performed can be adjusted. As long as the same device performs both functions, such mutual reinforcement of results is potentially possible without the need to reposition the subject / device or perceptually interrupt one inspection to perform the other inspection.

[0105] Aspects of some embodiments of the present disclosure relate to providing functions in an objective and subjective vision inspection device with a built-in display that facilitate guiding and / or controlling the subject's attention, eye convergence (interocular difference in visual angle), and / or lens adjustment. In some embodiments, these functions facilitate the combination of the vision inspection device with other devices that use an external screen (e.g., devices for teleconference and / or auxiliary vision inspection devices). In some embodiments, functions are provided that enable improvements related to the speed, comfort, accuracy, and / or automation of vision inspection.

[0106] In some embodiments, the image is delivered to both eyes simultaneously. This potentially facilitates the use of the inspection device to affect the state of the subject's eyes, for example, by manipulating the following factors. · Inter-pupil distance (IPD) that can be mechanically changed (e.g., by moving the exit pupils of the device optics horizontally away from or closer to each other). The system is configured to optionally have degrees of freedom to also mechanically adapt to other aspects of the subject's anatomy (e.g., corresponding to the relative vertical displacement of the subject's eyes and / or relative depth displacement with respect to the opposing plane). ·The convergence of the eyes that can be changed by changing the angles of the mechanical and / or optical elements of the system (e.g., mirrors and prisms) (however, prisms may cause chromatic aberration). Optionally, by moving the entire ophthalmic optical subsystem, there is a potential advantage that the optical axis can be kept constant after the eye itself adjusts its position to a new angle. For example, when viewing a target in the range of about 3 to 6 meters, an eye convergence of about 1° is typical, and when viewing a target in the range of about 0.4 meters, an eye convergence of about 3° is typical.

[0107] In particular, it should be noted that when the maximum field of view size of the presented image is relatively small (e.g., ±5°), by adjusting the eye convergence by the mechanical movement of the system, it is possible to ensure almost the entire area available for visual presentation. In some embodiments, the eye convergence is adjusted (additionally or alternatively) by moving the generated image left and right within the available field of view size of the retinal scanning display (i.e., digitally moving the image). The adjustment of the mechanical eye convergence provides the potential advantage (compared to the displacement of the digital image) of keeping the angle relative to the eye constant as the angle of the eye follows the new angular position. For example, potentially maintaining the angle at which an objective visual acuity test pattern is projected onto the retina.

[0108] In some embodiments, the composite inspection device is configured to generate and present inspection images and / or target images to one or both eyes of the subject internally. In some embodiments, the generated images are optionally delivered to the eyes through a beam combined with light collected from in front of the subject, and the subject views the generated images in combination with optically formed surrounding images (e.g., augmented reality or AR view). This may assist in the accommodation setting and / or control of the subject's lens. For example, any object (e.g., an attention - drawing object such as a toy that actually exists in the environment and / or is shown as a 3D image) can be shown to a child subject to draw the subject's attention through a pass - through image collected from the surroundings. Optionally, a person familiar to the child subject can draw the subject's attention from in front of the subject through the pass - through image.

[0109] In any case, surrounding objects potentially assist by providing a visual context familiar to the subject's visual system. The pass - through image may also facilitate the interaction between the subject and the ophthalmic examiner (optometrist), and for a technician (assistant), the subject's field of view need not be limited to that generated within the inspection device.

[0110] In some embodiments, the brightness of the generated images is adjustable (e.g., laser output, polarizer, filter, and an LC filter can be used to perform a vision test under target conditions (e.g., standardized, common, or optimal conditions according to the preference of the inspection administrator). Optionally, an adjustable polarizer, a transparent LCD, or other devices are used to adjust the surrounding brightness. This has the potential advantage of enabling the subject to comfortably view the inspection target under a wide range of ambient lighting conditions, and thus, the natural optical adjustment response of the subject to the actual position of surrounding objects can be utilized.

[0111] In some embodiments, the ambient passthrough facilitates a combination of the image presentation function incorporated in the inspection device with other displays such as a videoconference display and / or a special inspection display separately available in the inspection settings. For example, the subject can interact with the examiner (e.g., receive instructions or ask questions) displayed on the videoconference screen without necessarily interrupting the vision test or repositioning with respect to the vision testing device. The external screen may be used, for example, to present an image that attracts the subject's attention instead of an object such as a toy that attracts the subject's attention.

[0112] In some embodiments, the vision testing device includes support functions such as eye tracking, which more specifically includes any or all of eye position (e.g., convergence) tracking, accommodation tracking of the eye's lens, and / or pupil size tracking. The support function, in combination with the passthrough function, optionally enables the use of the device together with an external screen that presents stimuli for auxiliary evaluation, for example, for vision, visual attention, or other purposes. Regardless of whether the passthrough function is used and / or whether the passthrough function is present, the eye tracking function is optionally used internally to evaluate the validity of test results (e.g., objective vision tests) during different trials. Optionally, the impairment of the correct eye positioning is used as a trigger to take corrective and / or warning measures (e.g., repositioning of the device's optical pupil, change of the presented visual stimulus, discarding of bad data, or presentation of a warning to the device operator).

[0113] In some embodiments, the presentation of the image to both eyes or one eye appropriately varies according to the type and / or stage of the examination. For example, appropriate optical corrections for achieving good vision for the subject are alternately determined for each eye, and then, at the same time in binocular vision, for example, using an image aligned for binocular vision, the subject can be stimulated so that the subject can determine whether both eyes look equally well or one eye is significantly undercorrected compared to the other eye. For example, the test image is divided into sections of features that make up a single image, and at least some may be presented to only one eye or to only one eye at a time.

[0114] In some embodiments, the adjustment of the refractive power of the lens is under automatic control that enables an automatic examination.

[0115] Aspects of some embodiments of the present disclosure relate to providing cylindrical correction and axis correction to the optical system of a subjective visual acuity testing device and / or an objective visual acuity testing device. In some embodiments, the visual acuity testing device presents an image using a scanning display device.

[0116] In some embodiments, the cylindrical correction and axis correction are provided together with a visual examination system configured for objective measurement and / or subjective measurement of eye refraction, for example, to determine the corrective lens prescription of glasses and / or contact lenses. In some embodiments, the cylindrical refractive error correction unit is provided as an element of a virtual reality (VR) and / or augmented reality (AR) system.

[0117] A retinal scanning display (also known as a virtual retinal display, retinal scanning display, or retinal projector) projects an image onto the retina by the projection of appropriately patterned light. Such a display constructs an image directly on the retina not by relaying a conjugate image of a light source (e.g., a light source patterned in the scene of the image), but by scanning a light source (e.g., one or more lasers) over the surface of the retina in a rapidly intensity-modulated pattern. In practice, the light from the beam source is optically manipulated within the display so as to reach the entrance pupil of the eye from different directions rather than from a single (generally fixed) direction that each beam source actually occupies.

[0118] Accordingly, information regarding regions defined at different angles of the image scene is transmitted through the beams reaching the eye from those different angles. The image is accumulated over time, but is accumulated at a rate sufficient for a single image to be perceived. Regardless of the direction of arrival, the scanned beams reach the entrance pupil of the eye. For design purposes, the entrance pupil is optionally considered as a circle or ellipse with a diameter varying in the range of 2 mm to 6 mm, e.g., about 2 mm, 3 mm, 4 mm, 5 mm, or 6 mm. The actual entrance pupil of the eye can potentially be smaller (e.g., in high illumination conditions) or larger (e.g., when medically dilated), e.g., in the range of 2 mm to 8 mm or 2 mm to 10 mm.

[0119] The cornea and the lens focus the light entering the eye's pupil from a single beam onto a point on the retina. Accordingly, the generation of such an image is affected by the optical system of the eye itself, including spherical refractive errors and cylindrical aberration, which are routinely corrected in the normal way using glasses and contact lenses.

[0120] A retinal scanning display can generate an "imaging beam" internally (a beam that includes the full angle of the laser beam across the image frame), but when optical refractive power correction is applied to compensate for defects in the eye's optical system, they are mainly applied to the laser beam itself, and are applied regardless of how the laser beam is directed at any given instant. In other words, the laser beam at each instant corresponds to the "pixel" that should be optimally focused on the retina. In short, the optical correction is applied "within the beam".

[0121] Spherical aberration and / or astigmatism are generally corrected using an individually tailored (optically static) corrective lens. However, the use of a particular optical system (e.g., an ophthalmic examination system) depends on its ability to provide such correction. Potentially, certain virtual reality (VR) systems and / or augmented reality (AR) systems and / or users can benefit from such functionality.

[0122] Focusing on cylindrical correction, a basic arrangement for introducing an adjustable optical refractive power and / or the axial direction of cylindrical distortion into the wavefront of an optical system may simply involve providing lenses that produce multiple cylindrical distortions with different refractive powers and selecting the lens with the appropriate refractive power, depending on, for example, manually or by the movement of a carousel to replace other lenses within the system. In such a system, the cylindrical axis can be selected by rotating the lens around the optical axis.

[0123] Another arrangement for introducing adjustable optical power and / or axial direction of cylindrical aberration includes a plurality of lenses (e.g., a pair of lenses) arranged in a variable range in intersecting directions. For example, one lens may introduce negative optical power and the other lens may introduce positive optical power. When each lens has the same size, when they are aligned, a minimum amount of cylindrical power is introduced (e.g., not practically significant). When arranged orthogonally, the maximum amount of cylindrical aberration is introduced. Intermediate levels of cylindrical aberration are introduced by intermediate oblique crossing angles. For a given selected cylindrical power, the cylindrical axis direction can be selected by rotating the crossed cylindrical lenses by the same amount.

[0124] Accordingly, the crossed lenses, when positioned in the optical path, can effectively act as a single variable magnification cylindrical lens and provide potential advantages by reducing the need for replacement of optical system components.

[0125] However, the configuration for introducing cylindrical aberration into an optical system interacts with spherical correction and may adversely affect the focusing and calibration of the beam to the pupil of the optical system. This may be particularly relevant when the system is intended to function by varying one or both of the spherical and cylindrical powers. However, the inventors of the present disclosure have confirmed that there is a group of optical configurations that can contribute to the miniaturization and simplification of the device design and / or function while substantially excluding this problem as a limiting factor in the overall performance of the device.

[0126] Briefly, "convergence" is a characteristic of a beam containing non-parallel rays. For the entire beam (in geometric optics, for example, not necessarily considering wavelength-dependent effects), convergence is defined with respect to the curvature of the wavefront of the beam and the optical power (e.g., in diopters, with the unit being m -1) It is represented by. As the distance of the uncorrected beam from the light source increases, the convergence approaches zero (flat). This is similar to the fact that the local curvature of a sphere approaches flat as the sphere gets larger. The lens in the optical path brings about a change in the curvature of the wavefront. For example, it can be collimated (making the convergence approximately zero or parallel), increased, or decreased. This can include switching the sign of the convergence (e.g., switching a diverging beam to a converging beam). One convention for roughly depicting the beam along the optical path is to depict the path of at least one of the outer (limiting) rays of the beam. In such a case, the angular change of the limiting ray with respect to the optical axis can be used as a measure of the convergence.

[0127] Scanning beam optical systems such as retinal scanning displays generate "superimposed" vergences. That is, it generates a vergence (referred to herein as intra-beam vergence) that describes the wavefront curvature of individual laser beam positions and a vergence (referred to herein as inter-beam vergence) that describes the wavefront curvature of the set of scanned beam positions. In a scanning beam optical system, the presence of multiple vergences imposes design constraints that affect the state of the beam at the entrance pupil and / or exit pupil (the positions that image the (physical) aperture within the optical path) of the beam. In a system intended to illuminate the retina of the eye, the relevant aperture at which these pupils image can be the (anatomical) pupil of the eye itself. If the vergences of the laser beam (within the beam) and the scanning beam (between the beams) are not properly managed to converge at the entrance pupil of the illumination optical system, part of the illumination and the field of view are lost, and the quality of the beam that can enter the entrance pupil of the eye and form an image on the retina deteriorates.

[0128] In particular, there is a potential problem of introducing cylindrical correction into the beam without disturbing the relationship between the beams (for example, without preventing focusing at the entrance pupil). For example, a cylindrical lens (which may be an adjustable cylindrical lens or a cylindrical lens including an arrangement of two or more lenses that "act as an adjustable cylindrical lens") can be placed in the optical path and can produce a cylindrical correction effect on the in-beam convergence. However, at many positions (for example, positions far from the inter-beam pupil), this also causes a change in the inter-beam convergence.

[0129] In some embodiments of the present invention, cylindrical correction is applied to the illumination beam of the retinal scanning display by arranging two lens groups composed of one or more cylindrical lenses in the optical path of the illumination beam. In some embodiments, the first and second lens groups are arranged (and held) to have the same shared cylindrical axis, and in some embodiments, the same shared cylindrical axis is changeable (for example, by rotation).

[0130] This can cause different effects between the inter-beam convergence and the in-beam convergence. In some embodiments, this different effect is a negligible change in the inter-beam cylindrical convergence, but a significant (for example, astigmatism correction) level of change in the in-beam cylindrical convergence. In this case, since the magnitude of the inter-beam convergence is relatively small with respect to the overall width of the beam, the difference in the influence according to the distance along the optical path is relatively negligible. For example, the change in the inter-beam convergence introduced by the first group encountered first on the beam path can be effectively canceled by the second group encountered (which may have an opposite diopter sign). To achieve cancellation, the two groups may have the same optical refractive power of the same diopter magnitude or may be slightly different. Optionally, the difference is selected to correct for the fact that the influence of the distance offset is relatively small.

[0131] Thus, in some embodiments, one group is disposed near the in-beam waist and one group is disposed further away. The positions and strengths of the two lens groups are selected such that the change in in-beam convergence induced by the further of the cylindrical lens groups exceeds (is greater than) the change in convergence induced by the nearer of the cylindrical lenses, introducing cylindrical distortion, while the change in between-beam convergence induced by the two lens groups is substantially reduced.

[0132] In some embodiments, the amount by which one lens group exceeds the other can be selected such that the magnitude of the change in overall in-beam cylindrical convergence is at least -8, -6, -5, -4, -3, or -2 diopters (negative), and / or at least +2, +3, +4, +5, +6, or +8 diopters (positive). Optionally, the position of the same lens can be adjusted such that the magnitude of the in-beam cylindrical convergence changes continuously, or, for example, in steps of at least about 0.1, 0.125, 0.2, or 0.25 diopters. Optionally, at least 10 different magnitudes of overall in-beam convergence change can be selected between the maximum and minimum magnitudes. In some embodiments, both positive and negative overall convergence changes (e.g., changes in diopter units) can be selected. In some embodiments, the overall selectable range in diopter change includes both positive and negative diopters and is at least 2, 4, 6, 8, 10, 12, or 16 diopters.

[0133] In some embodiments, one or more groups of first and second cylindrical lenses have opposite diopter signs. Further, in some embodiments, they are similar within a similar size, for example, within 50%, 25%, 10%, or 5%. In some embodiments, first and second groups of one or more cylindrical lenses are disposed on both sides of the beam waist. The optical refractive power may be split between two or more lenses in one or both groups. The lenses within the lens group are optionally arranged along an optical path section (e.g., a telecentric zone) and arranged to approximate the effect of a single lens (a "virtual lens") occupying the position between these lenses.

[0134] In some embodiments of the present invention, cylindrical correction is performed using a system having the following features. · At least two cylindrical lenses are provided. · These lenses are configured to produce a final effect on the in-beam convergence that varies within the practical range of astigmatism encountered in refraction (e.g., -2 to 2 diopters, -3 to 3 diopters, -4 to 4 diopters, -6 to 6 diopters, or -8 to 8 diopters). · However, the opposing optical refractive powers of the cylindrical lenses are sufficient such that the final effect on the inter-beam convergence is negated to the extent that it does not significantly impair the focusing of light into the eye's entrance pupil, which is sufficient to display at least a complete examination image.

[0135] Thus, in some embodiments, at least one first cylindrical lens and at least one second cylindrical lens are provided, and the first and second cylindrical lenses (or lens groups) impose opposing convergence effects on the inter-beam convergence.

[0136] Regarding "not significantly impaired" used for the above-mentioned entrance pupil formation, "being significantly impaired" may be functionally evaluated according to the performance of the subject undergoing the vision test. In this case, the performance should not be adversely affected (compared with the actual or estimated "perfect" pupil). For example, the performance of the subject is not measurably and discriminably adversely affected from the viewpoints of the accuracy of the test, the test speed, and / or the comfort of the subject (by self-report). Potential causes of performance degradation due to inappropriate optical pupil formation (if it occurs) include, for example, peripheral dimming (e.g., relative darkening at the edge of the image), partial loss of visibility of the test target, difficulty in recognizing the presented test target, and / or difficulty in distinguishing differences in the test target between different conditions.

[0137] In some embodiments, "not significantly impaired" is determined with respect to device parameters, and the determination includes, for example, one or more of the following criteria. · The angular size of the test image shown to the subject completely includes a specified region of interest (both in the vertical and horizontal directions) extending over at least 1°, 2°, 3°, or 10°. For example, the region of interest can be defined based on the size and / or resolution of the test target. · An image display device can generally be regarded as forming an optical pupil for the eye by aligning, with a lens, the foci of all beams that each start at approximately the same angle of incidence with respect to the lens to approximately the same position. In a system where the individual beams are approximately parallel or nearly parallel to each other (e.g., a telecentric or nearly telecentric zone), after the focusing lens, all the beams form an optical pupil at approximately the same position, and the diameter of the beam at this position defines the diameter of the optical pupil. When applying a cylindrical refractive power, the system can be regarded as having two optical pupils distributed along the optical axis according to the influence of the cylindrical refractive power on each axis. At one extreme, the first pupil is formed by the beam maximally shifted by the variable cylindrical optical refractive power. On the other hand, there is a second pupil formed by the beam placed at a position substantially unaffected by the axis of the selected cylindrical optical refractive power, which is the position of the "original" pupil. If the positions of the two optical pupils do not coincide sufficiently, some beams (e.g., the beams most affected by the cylindrical optical refractive power) spread "fan-like" from the "home" pupil or have not yet converged to the "home" pupil, so a pupil with a larger diameter is found at the "original" (without cylindrical correction power) position of the optical pupil. Under such conditions and, optionally, in the range of cylindrical adjustment of at least 2, 3, 4, 5 or more diopters, the ratio of the diameters of the optical pupil (i.e., the longest and shortest diameters in the directions with and without the cylindrical optical refractive power respectively) is, for example, less than about 3, 2.5, 2, 1.5, or 1.1. · All parts of the region of interest of the inspection image provide a maximum retinal illuminance level within at least 15% of a nominally sufficient average level for the specified function of the device (e.g., visual inspection, or other image presentation). Optionally, the threshold is at least 25%, 33%, or 50%. · In particular, in applications where the brightness of the image is a limiting factor (i.e., applications where reducing the maximum brightness to achieve overall uniformity reduces one aspect of usability), the maximum brightness in the most brightly irradiable area is less than 50% of the maximum brightness in the most dimly irradiable area. This can be understood as an index for measuring the amount of illuminance compensation required to overcome defects in the formation of the optical pupil.

[0138] By placing the cylindrical lens at a position where the laser beam at each position of the larger scanning beam has a waist (i.e., the narrowest point between two wider areas), the disturbance of the beam's internal convergence can potentially be minimized.

[0139] For example, when placing a cylindrical lens with a focal length F2 behind a spherical lens with a focal length F1, the focal point changes according to the refractive power of the lens along its axis and their distances on each axis. Since the cylindrical lens has refractive power on a single axis, its axis is corrected and the other axes are not affected. By rotating the cylindrical lens, the axis that is affected can be selected.

[0140] Changing the distance D between the lenses causes the focal point F T of the affected axis to change according to Equation 1.

Equation

[0141] The distance between the "new focal point" and the second lens is the back focal length (BFL) shown in Equation 2.

Equation

[0142] Therefore, when the distance between the lenses (D) approaches the focal length F1, BFL = 0. At this position, the convergence of the beam is not affected, and only the width is affected.

[0143] When a third lens is placed at a position behind the foci of the above two lens systems and at a distance equal to its own focal length from the focus of the unaffected axis, the light rays are collimated on its axis. However, when BFL≠0, they are not collimated on the axis selected for positioning the cylindrical lens. Thus, by rotating the lens, the convergence at the selected axis can be changed.

[0144] The cylindrical correction introduced into the illumination path of the scanning display may be used in vision testing and / or in the examination of refractive errors of the eye, and is described in detail, for example, in connection with FIGS. 8 - 15. In some embodiments, the built-in cylindrical correction enables the user of a retinal scanning display device used for general display purposes to obtain a clear image without necessarily using other corrective lenses (e.g., regular glasses), which has potential advantages for the size of the device and comfort during wearing (e.g., less space needs to be reserved for wearing glasses together).

[0145] In some embodiments, a cylindrical correction lens (adaptive lens) with an optically refractive power and / or axis that is essentially adjustable is used. For example, a liquid lens and / or a liquid crystal lens may be mentioned. Such lenses are optionally placed in the optical pupil of the optical system, and by being placed in the optical pupil, they may have a selective effect on the beam internal convergence. This embodiment is used together with this type of arrangement, unless explicitly limited to the use of other arrangements for providing cylindrical correction as an option. For example, the cylindrical correction unit 214 can generally be implemented using such an arrangement (and perhaps can be replaced by the arrangements of other embodiments described herein), and can be moved to a more appropriate position (e.g., the optical pupil) on the optical path as appropriate. During the lifespan of patents that may mature from this application, new related forms of essentially adjustable lenses, including those mentioned here as liquid lenses and / or liquid crystal lenses, are expected to be developed. The term "essentially adjustable lens" is intended to encompass all such new technologies preemptively.

[0146] The embodiments of the present disclosure are described particularly with respect to retinal scanning displays, but it should be understood that other display types (especially miniaturized display types) are optically used. For example, the retinal scanning display laser and the MEMS mirror can be replaced and appropriately coupled to the rest of the system using an appropriate adapter optical system. The characteristic of a highly miniaturized display device is the ability to generate and form an image and / or an image beam from within a light source whose optical cross-section perpendicular to the optical path is about 10 cm 2 Hereinafter, 6.5 cm 2 Hereinafter, 4 cm 2 Hereinafter, or 1 cm 2 and is within the range of the following, and form. However, in some embodiments of the present disclosure, less miniaturized display devices are used as an option.

[0147] For example, in some embodiments, a micro-LED (also referred to as mLED or μLED) display replaces one or more image beam generation elements in any of FIGS. 1A - 20C with an appropriate adapter optical system as appropriate. In some embodiments (e.g., embodiments that implement a part of the embodiments of these figures), another display technology is used. For example, μOLED, LED, OLED, QDLED, LCD, LCOS, DLP, or other technologies are used. During the lifespan of patents that may mature from this application, new related miniaturized display technologies, including those mentioned here or otherwise, are expected to be developed or enter the market. The term "display" is intended to preemptively include all such new technologies.

[0148] Before detailing at least one embodiment of the present disclosure, it should be understood that the present disclosure is not necessarily limited to the details of the structure and arrangement of components and / or methods described in the following description, shown in the figures, and / or exemplified in the examples in its application. The features described in the present disclosure, including the features of the present invention, can be implemented in other embodiments or in various ways.

[0149] Cylindrical correction Referring to FIG. 1A, a cylindrical refractive error correction unit according to some embodiments of the present disclosure is schematically shown.

[0150] In some embodiments, the cylindrical lens arrangement has two cylindrical lenses 6, 8 within a telecentric zone 10 established by two lenses 2, 4. However, the individual beams are not collimated in zone 10.

[0151] The image that is finally projected onto the retina is generated by a light source 20 on the left side of the figure. Although the details of the implementation of this light source are not shown in FIG. 1A, for example, as described in connection with any of FIGS. 8-15 of this specification, it may be implemented as a scanning retinal display or as another type of display (e.g., one incorporating modifications, as described in connection with FIG. 5B). The embodiment of FIG. 1A is provided optionally as an embodiment of these figures, for example, as an embodiment of the cylindrical correction unit 214. Beyond the exit pupil position 14 on the right side of the figure, the light is ultimately relayed through the additional optical system of the ophthalmic examination device to the patient's own pupil and retina, for example, to perform a subjective visual acuity examination.

[0152] The selected individual laser beams 1A - 1C are each depicted at different distances as three non - parallel lines (rays) representing the width of the laser beam (outer or "limiting" rays) and the centerline. The waist position 15 indicates the position of the narrowest region of the beams 1A - 1C along the length of the telecentric zone. For the overall image that the patient sees, the beams 1A - 1C should overlap the centerline beam within the region of the exit pupil at the exit pupil position 14 (and also with the patient's own pupil).

[0153] In some embodiments, the light source 20 comprises a laser and one or more scanning mirrors. It operates by rapidly scanning the laser beam in a two - dimensional pattern angled outward to fill the collimating lens 2. For illustration purposes, the beam arrives at an angle that the collimating lens 2 makes parallel and is depicted to create the telecentric zone 10. This can be somewhat modified to change the spherical correction refractive power. Optionally, the spherical correction is applied by a separate optical system, for example, as described in connection with FIGS. 8 - 15 in this specification.

[0154] To vary the direction of the cylindrical refraction, the cylindrical lenses 6, 8 can change the direction of the cylindrical correction by rotating around the optical axis. To provide a variable refractive power, at least one of the cylindrical lenses 6, 8 (lens 6 in the illustrated embodiment) is movable along the optical axis. This changes the corrected cylindrical refractive power applied to the image seen by the patient. The farther the cylindrical lens is from the waist position 15, the greater the correction applied. In some embodiments, the cylindrical lenses 6, 8 are aligned with each other at their respective cylindrical axes. For example, they are exactly aligned or aligned within at least 5°, 3°, or 1° of each other. It should be understood that these degree values are available for other examples of aligned cylindrical axes as well, as long as they are appropriately changed and are not incompatible or otherwise specified.

[0155] As discussed in the summary description, providing a second cylindrical lens has potential advantages because there are two different "convergences" that must be co-managed along the optical path. For example, at each position of the scanning pattern, the rays of the laser beam can be initiated substantially parallel (not focused, corresponding to a low beam in-convergence). However, the beams at different positions of the scanning pattern are widened relative to each other (e.g., "negative" between-beam divergence). Both convergences present within the same overall system are changed in different ways by the lenses the beam encounters. In particular, as indicated by the intersection lines defining each laser beam 1A - 1C including the beam waist position 15, the in-beam divergence is not parallel (not collimated) in the telecentric zone 10. In contrast, the between-beam divergence is parallel or nearly parallel.

[0156] The position of the single cylindrical lens 6 changes both convergences in the telecentric zone 10. Changing the in-beam divergence gives the desired effect on the optical refractive power at the selected axis. However, changing the between-beam divergence affects the convergence at the exit pupil and may prevent some beams from entering the subject's pupil.

[0157] By introducing an inverse refraction lens 8 having a refractive power opposite to that of lens 6, the overall impact on the actual beam convergence can potentially be significantly reduced. For example, lens 8 introduces a non-parallel beam convergence that is largely canceled out by lens 6 after a short distance. From this arrangement, when the distance that lens 6 moves when changing the cylindrical refractive power is kept short, the exit pupil size at the exit pupil position 14 does not change significantly. That is, over a relatively large range of lens positions, substantial cancellation of the beam convergence occurs.

[0158] Thereby, the two rotatably aligned lenses 6, 8 can have substantially similar effects across the entire telecentric zone 10. In contrast, the impact of the lens on the beam convergence within the beam depends strongly on the distance from the waist position 15, as the impact becomes proportionally weaker with respect to the cylindrical correction as the lens approaches the waist position 15.

[0159] In some embodiments, this module or unit for optical cylindrical correction has two rotatable cylindrical refractive units (e.g., single lenses or lens groups) located in the telecentric zone of the optical system, and is equipped with means for introducing cylindrical correction into one or more scanned laser beams. At least one unit is movable along the axis of the telecentric zone, producing a variable final effect on the beam convergence within the beam. The cylindrical axes of the two units are similarly oriented and have complementary optical refractive powers selected to largely cancel out their mutual influence on the beam convergence.

[0160] In some embodiments, one or more scanned laser beams are used in a retinal scanning display system.

[0161] Also, in some embodiments, the scanned laser beam is generated as part of the illumination system of an ophthalmic device having both objective refractive error vision testing capabilities and subjective refractive error vision testing capabilities (e.g., testing for an eyeglass prescription). At least the subjective test utilizes a portion of the optical path incorporating two cylindrical refractive units. For example, in the subjective test, a retinal scanning display generates a target image and the cylindrical correction is adjusted until the target is seen clearly according to the patient's report. In the objective test using the same device, the retinal scanning display can be used to generate a target image that guides the direction and distance of the visual focus (accommodation of the subject), but the optical system of the other parts of the system provides the test illumination and measurement functions.

[0162] Note that the optical elements from lens 2 to lens 4 (in particular, the optical subsystems of lenses 6, 8) are operable with any suitable illumination source as long as the beam reaching lens 2 (or other optical arrangement) interacts with it and generally maintains the position of the exit pupil of the optical system. For example, the magnitude of the beam convergence is sufficiently reduced so that the cylindrical correction can be introduced separately while maintaining the beam incidence on the pupil of the eye being examined. In some embodiments, this includes being able to view the projected image after it reaches the retina, for example, without interfering with the test results due to vignetting or loss of the field of view of the projected image. The optical elements including lenses 6, 8 may be provided as part of a relay section in front of the optical path, after a folding mirror, after a beam splitter, or other suitable arrangement that interacts with the illumination beam.

[0163] Referring to FIG. 1B, a cylindrical refractive error correction unit according to some embodiments of the present disclosure is schematically shown.

[0164] Except as otherwise indicated below, the elements shown in FIG. 1B generally correspond to the elements of FIG. 1A, and the embodiment shown in FIG. 1B can be used to provide cylindrical correction to the optical system as described in connection with FIG. 1A.

[0165] In some embodiments, the final refractive power of the cylindrical lens 8 of FIG. 1A is split between two or more lenses 8A, 8B on either side of the cylindrical lens 6. The lenses 8A, 8B can change the overall final cylindrical refractive power (including the lens 6) from a positive diopter to a negative diopter and are positioned such that, optionally, the change can be made while moving a single lens. By appropriate selection of the lenses, the "average" position of the lenses 8A, 8B can be optically brought closer to the middle of the telecentric zone 10 than the lens 8 (e.g., can be placed on the right side of the waist position 15), so that the splitting enables the change of the final cylindrical refractive power. Thus, the cylindrical lens 6 can be moved to either one of its positions.

[0166] Referring to FIGS. 2A-2B, according to some embodiments of the present disclosure, the pupil effect due to the introduction of cylindrical correction in a one-lens and two-lens cylindrical correction unit is schematically shown.

[0167] For the optical system defined as follows, the pupil effect is simulated. In both FIGS. 2A and 2B, the shaded area represents a nominally 4 mm diameter pupil. In the example shown, the system is designed to have an optimal pupil in the cylindrical correction of -2 cylindrical refractive power. The pupil dispersion results (pupil size) shown are for cylindrical corrections of ±2 diopters of this value. For the sake of explanation, a 1:1 relay is assumed. As the relay magnification increases, the effect on pupil dispersion may increase, and such cases are assumed at least in a scanning retinal display device. For example, in some embodiments, a relay magnification in the range of 1:1 to 1:8 is used. For example, 1:1.5, 1:2, 1:3, 1:4, 1:5, 1:8, or other relay magnifications are used. These values are optionally applicable to any of the embodiments described herein.

[0168] In FIG. 2A, in order to introduce spherical aberration into the wavefront, a single cylindrical lens having a refractive power of 8 diopters is used (for example, corresponding to lens 6 in FIG. 1A, and lens 8 is not provided).

[0169] In FIG. 2B, spherical aberration is introduced into the wavefront by using two cylindrical lenses with refractive powers of 8 diopters (moving) and -10 diopters (stationary) of opposite signs (for example, corresponding to both lens 6 and lens 8 in FIG. 1A).

[0170] Therefore, regions 251A to 251C (FIG. 2A) and region 251 (FIG. 2B) represent the divergence of the beam due to the introduction of -4 diopter cylindrical correction. Regions 252A to 252C (FIG. 2A) and region 252 (FIG. 2B) represent the beam divergence due to the introduction of 0 diopter cylindrical correction.

[0171] In FIG. 2A, the crescent-shaped beam loss portion (for example, the portions corresponding to regions 251A, 251C, 252A, and 252C) that falls outside the shaded region 412 represents the lost light, resulting in a deterioration of the image quality.

[0172] In FIG. 2B, since the divergence of the beam is indistinguishable, each condition is represented by only one region (regions 251 and 252). There is no loss of light in the pupil due to pupil divergence.

[0173] As described above, a larger cylindrical correction and / or a larger magnification by relay tend to exaggerate the effect. For example, in a single cylindrical correction mode, some beams may not enter the pupil 412 at all. Note that since the cylindrical correction is applied only along one axis, there is no horizontal divergence. Optionally, this can be used as a reference for evaluating the magnitude of pupil divergence under various conditions for the axis orthogonal to the axis of maximum divergence.

[0174] Referring to FIGS. 3A-3B, according to some embodiments of the present disclosure, an optical system 101 including a subjective inspection optical subsystem and an objective inspection optical subsystem is schematically shown. In this embodiment, the light source 20 also acts as the objective inspection illumination source 200. This is optically manipulated with the subjective pathway illumination enabled for use as a target for focusing and / or relaxation of focusing by the subject.

[0175] Elements 20, 2, 8A, 6, 8B, and 4 correspond to the names shown for the adjustable cylindrical correction unit of FIG. 1B and include, for example, a cylindrical correction unit 214 as described with respect to FIGS. 8-15.

[0176] The beam splitting optical system 300, lens 402, any folding mirror 404, collimating optical system 204, beam splitter 406, beam combiner 408, objective inspection detection unit 102, relay lens 400, folding mirror 502, relay lens 500, eye 108, pupil 412 of the eye, and retina 110 correspond to the elements of the same number described in connection with FIGS. 8-15 of this specification. However, the relay lens 400 is shown here after the beam splitting optical system 300, and the role of collimating the optical path for objective inspection is taken over by the collimating lens 2 of the cylindrical correction unit.

[0177] Referring to FIG. 4, an optical system 101 providing a separate objective inspection illumination source 200 according to some embodiments of the present disclosure is schematically shown.

[0178] Some elements of the subjective inspection illumination optical path include elements 20, 2, 8A, 6, 8B, 4 of the cylindrical correction unit 214, except that the light source 20 does not provide the objective inspection illumination source, and are unchanged from those of FIGS. 3A-3B. The relay lenses 400, 500 and the folding mirror 502 are also shown again.

[0179] The scale bar 550 indicates the approximate size of the optical arrangement of FIG. 4. As an example, it can be understood that the arrangements in other embodiments are similarly scaled in some embodiments. For example, the beam envelope in the telecentric region of the beam path is about 2 cm wide. These measurements are not limiting. As described in the present disclosure, the refractive power of a particular lens, the arrangement of the folding mirror, the length of the telecentric zone, the focal length, and other parameters of the system can be optionally changed in appropriate relationships to maintain the overall functional relationship between the optical elements and the function of the entire optical system, e.g., the function as described herein, which will be readily understood by those of ordinary skill in the art. For example, the example of the focal length of a lens can be estimated from the pupil and / or focal positions shown in various figures.

[0180] The objective examination is performed through an optical path in which a beam from the objective examination illumination source 200 is incident on the beam splitter 301 and directed through the beam combiner elements 408A, 408B (corresponding to the beam combiner element 408 of other embodiments) to the eye pupil 412 and the retina 110 of the eye 108. The return light passes through the beam splitter 301 and the relay lenses 402, 401 and reaches the detection unit 102.

[0181] It should be noted that the arrangement of the beam combiner elements 408A and 408B opens an unobstructed optical path that is linearly guided from the eye 108. In some embodiments, the beam combiner element 408B is provided as a partially reflective mirror, and light that travels straight through it can also be coupled. In some embodiments, the beam is configured to generate a focused image of the scene on the other side of the optical system onto the retina using, for example, an appropriate arrangement of one or more prisms that optionally include lenses and / or mirrors. This has the advantage of being able to prompt the accommodation of the lens and / or the positioning of the eyes by allowing the subject to view the actual surrounding distance. The relative illumination from the scene and / or the illumination inside the device (e.g., the subjective examination target beam) are appropriately adjusted so that each can be visually recognized simultaneously, providing an appropriate visual contrast. Optionally, the examination target is presented so that the subject perceives that the examination target is present in the scene at a specific distance (e.g., generating an image that is appropriately focused and optionally appropriately converged and aligned for binocular vision). Optionally, for example, when examining a child or a subject with difficulty in communication, the examiner can utilize the surrounding passage to present a physical object that is available at any distance within the examination space and that attracts attention to assist the examination process.

[0182] In some embodiments, additionally or alternatively, by passing through the combiner element 408B, light rays generated from an additional display device (e.g., an integrated display screen) can be captured, or it is a larger display screen installed around. This has potential advantages such as enabling a remotely monitored examination session where, for example, a subject wearing the device can see an examination supervisor (examiner) communicating via the screen and, optionally, can interact with the examination supervisor. The examination supervisor, optionally, provides all necessary assistance to the subject via a communication link. Optionally, there is a on-site assistant (technician) to assist with part of the arrangement. Optionally, the examination supervisor can supervise multiple examinations simultaneously. For example, during a remote communication session involving multiple subjects and examination devices, individual or group instructions can be given, and both individual and group interactions are possible depending on the situation and details of the local remote communication device configuration. The examinations presented can include objective vision tests and / or subjective vision tests in any suitable order, and optionally, subjective and objective tests may be at least partially performed simultaneously.

[0183] By appropriately adjusting the optical system, an arrangement that passes ambient or auxiliary displays can be provided as an option along with the other embodiments shown here.

[0184] Additional details regarding the functions of the various components and / or subsystems of FIGS. 3A - 4 are described in connection with the remaining figures shown here, including the embodiments described in connection with FIGS. 6 - 20C.

[0185] Combined cylindrical correction and spherical correction Referring to FIG. 5A, a schematic illustration of a combination of a cylindrical refractive error correction unit 214 and a spherical refractive error correction unit 218 according to some embodiments of the present disclosure is shown.

[0186] The details of the cylindrical refractive error correction unit 214, as described in connection with FIG. 1A, include the lenses 2, 4, 6, 8 in this example, but this example should not be construed as limiting.

[0187] Also shown is an eye 108 having relay lenses 400, 500, and a retina 110 and an anatomical pupil 412.

[0188] Within the spherical correction unit 218, two fixed mirrors 522, 523 in the main beam path and a pair of movable mirrors 521 that return light reflected by the mirror 522 from the initial direction of the beam path to the mirror 523 are shown, and the light from the mirror 523 travels toward the relay lens 500.

[0189] The movable mirror 521 moves toward or away from the mirrors 522, 523 to lengthen or shorten the overall beam path. Thereby, the spherical aberration of individual beams is adjusted, for example, whether to focus at the position of the retina 110, in front of the position of the retina 110, or behind the position of the retina 110 is changed. Since the beams are collimated with each other, the overall beam envelope does not change by adjusting the position of the movable mirror 521.

[0190] Screen illumination source Referring to FIG. 5B, a cylindrical refractive error correction unit 214 combined with a screen illumination source 20A according to some embodiments of the present disclosure is schematically shown. In some embodiments, the screen is a display panel. For example, μLED, μOLED, OLED, QDLED, LCD, or other display technologies are used.

[0191] The functions of the lenses 4, 6, 8 in this example are as described in connection with other embodiments that provide cylindrical aberration correction. A pupil 14 is formed at the tip of the relay lens 4 and is conjugate with the pupil 412 formed in the eye 108 after passing through the relay formed by the relay lenses 400, 500. Also shown is a retina 110 where an image of the screen 20A is formed during a visual acuity test.

[0192] Since the screen illumination source 20A is initially spatially extended, it can be considered to serve both the roles of the light source 20 and the relay lens 2, as described in relation to FIG. 1A. The spread of light from each pixel of the screen illumination source 20A may be angularly wider than shown. The illustration shows only the envelope of the optical path passing through the pupil 14. Adjusting the position of the screen illumination source 20A along the optical axis acts to adjust the spherical correction refractive power (e.g., to perform the function of the movement of the movable mirror 521 in FIG. 5A).

[0193] Ophthalmic refractometry system Referring to FIG. 6, a block diagram of an optical system 101 combining an objective ophthalmic refractometry subsystem and a subjective ophthalmic refractometry subsystem according to some embodiments of the present disclosure is schematically shown.

[0194] In some embodiments, the subjective inspection subsystem and the objective inspection optical subsystem of the optical system 101 share the combined use of a retinal scanning display device used to generate inspection images. In some embodiments, the optical system 101 includes an objective illumination unit 100 (which generates illumination that is reflected and measured to determine objective inspection results), an objective inspection detection unit 102 (which detects the reflected objective inspection illumination light), a subjective inspection illumination unit 104, and a scanning unit 106.

[0195] Optionally, the scanning unit 106 includes a scanning mirror such as a MEMS (micro electromechanical system) mirror, a galvanometer mirror, or other reflective or transmissive element used to generate beam scanning. For objective measurement, the objective inspection illumination unit 100 irradiates the eye to be examined 108. A part of the light reflected by the layer of the eye to be examined 108 returns to the objective inspection detection unit 102. The reflected light reaching the objective inspection detection unit 102 contains refractive information from the eye to be examined 108. For subjective measurement, the subjective inspection illumination unit 104 emits one or more beams (e.g., beams of different colors) that are two-dimensionally scanned by the scanning unit 106 (i.e., deflected to different angles that change rapidly over time to create the impression of a single image). The scanned light is incident on the eye to be examined 108 and forms an image on the retina 110 of the eye to be examined. Optionally, the subjective inspection illumination unit 104 and the scanning unit 106 are used to form an image (focused or unfocused) to fix the gaze of the eye to be examined 108 and / or control the accommodation of the lens (e.g., relaxation of accommodation) during objective inspection.

[0196] Optionally, the optical system 101 includes a keratometry unit 112. The keratometry unit 112 is configured to measure the corneal shape of the eye to be examined. This makes it possible to obtain and / or confirm further information regarding the optical function of the eye to be examined 108. For example, information regarding astigmatism, the axis of astigmatism and / or the total corneal refractive power, or the radius of curvature of the cornea is included.

[0197] Referring to FIG. 7, FIG. 7 schematically shows a block diagram of a modification of the optical system 101 that combines an objective eye refraction inspection subsystem and a subjective eye refraction inspection subsystem according to some embodiments of the present disclosure and has a shared scanning unit 106.

[0198] The optical system 101 of FIG. 7 also includes an objective examination illumination unit 100, an objective examination detection unit 102, a subjective examination illumination unit 104, and a scanning unit 106. In this example, one or more beams emitted from the objective examination illumination unit 100 are directed by the scanning unit 106 towards the eye under test 108, and the impact position and / or angle of incidence on the eye 108 are affected by the position of the scanning unit 106.

[0199] Then, a portion of the light is reflected by a layer within the eye under test 108 and returns to the objective examination detection unit 102. The reflected light reaching the objective examination detection unit 102 contains refractive information from the eye under test 108.

[0200] Similarly to the above, the subjective examination illumination unit 104 emits one or more beams that are two-dimensionally scanned by the scanning unit 106. The scanned light is incident on the eye under test 108 and forms an image on the retina 110 of the eye under test. Optionally, the subjective examination illumination unit 104 and the scanning unit 106 are used to fix the fixation of the eye under test 108 during the objective examination or to control the accommodation of the lens (e.g., relaxation of accommodation) by forming an image (focused or unfocused). Light from the two light sources can be presented simultaneously (e.g., when the light from the objective examination illumination unit 100 and the light from the subjective examination illumination unit 104 are separated by characteristics such as wavelength and polarization so as not to interfere with the function of the objective examination detection unit 102), or optionally presented alternately at high speed.

[0201] Optionally, the optical system 101 includes a corneal measurement unit 112. The corneal measurement unit 112 is configured to measure the corneal shape of the eye under test. Thereby, further information regarding the optical function of the eye under test 108 can be obtained and / or confirmed. For example, information regarding astigmatism, the axis of astigmatism and / or the total corneal refractive power, or the radius of curvature of the cornea is included.

[0202] Optical module of an eye refraction examination system Referring to FIG. 8, a block diagram showing an optical module of a variant of an optical system 101 that combines an objective eye refraction examination subsystem and a subjective eye refraction examination subsystem and has a shared scanning unit 106 according to some embodiments of the present disclosure is schematically shown. In some embodiments, the optical system 101 of FIG. 8 corresponds to a more modular and detailed illustration of the optical system 101 of FIG. 7. In particular, the display of common units as specific options is shown together with the details of specific modularizations of the correction optical system and the relay optical system.

[0203] In some embodiments, the objective examination illumination unit 100 itself includes an objective beam source 200 and an associated collimating / condensing optical system 202.

[0204] The beam source 200 includes, for example, one or more light-emitting diodes and / or laser diodes such as edge emitters or VCSELs in the infrared range (>640 nm). Optionally, the beam source 200 generates light in other wavelength ranges, such as visible light or the UV range.

[0205] The collimating / condensing optical system 202 includes, for example, one or more lenses (spherical and / or cylindrical lenses) configured to collect and / or collimate the beam emitted from the beam source 200. The collimating optical system and / or the condensing optical system 202 may optionally include a pinhole of a fixed or variable diameter.

[0206] In some embodiments, the scanning unit 106 and the collimating optics 204 form a functional group of modules that shape and send a beam from the objective inspection illumination unit 100 towards the eye. For example, the collimating optics 204 includes one or more lenses, and the one or more lenses are movable along the optical axis of the beam. Additionally or alternatively, the collimating optics 204 includes one or more adjustable lenses. For example, lenses that change the focus by electrically controlling the curvature of the interface between two immiscible liquids, or lenses that change the focus in other ways, are included.

[0207] From the collimating optics 204, the beam from the objective inspection illumination unit 100 is sent to an optics-to-eye 206 that is optically configured to direct the beam towards the eye under test 108. For example, the optics-to-eye 206 includes one or more lenses and / or folding mirrors. Optionally, the optics-to-eye 206 includes one or more optical elements that combine or separate the beams. In some embodiments, these include optical elements (e.g., dichroic beam splitters) that transmit or reflect light depending on the wavelength of the light. The optical element is optionally configured, for example, to pass IR light while reflecting visible light. Optionally, the optical element reflects a portion of the IR light and passes another portion, such that, for example, the light can pass through the optical element and reach the eye, but then at least a portion (preferably a majority, e.g., at least 50%, 60%, 70%, 80%, 90% of the returning light) is directed towards the detector when it returns from the eye. Also provided are optical elements having refractive properties sensitive to polarization. For example, from this element, s-polarized light refracts differently from p-polarized light. In some embodiments, diffractive beam combiners or splitters, or diffractive optical elements such as optical waveguides, are provided. The splitting / combining element is arranged to appropriately direct light from different light sources of the optical system 101 towards the eye 108, or to direct light reflected from the eye 108 towards an appropriate detector, such as the objective inspection detection unit 102.

[0208] The objective examination detection unit 102 is configured to detect the reflection from the eye to be examined 108, and in particular, to detect the light received by the eye to be examined 108 from the objective examination illumination unit 100. In some embodiments, the detector of the objective examination detection unit 102 includes one or more photodiodes, a CCD camera, a position sensitive detector (PSD), and / or other optical sensors. Optionally, the objective examination detection unit 102 includes an optical system configured to (at least generally) correct the refractive power of the eye to be examined 108 and focus an image of the retina 110 on the detector. By way of example, a movable and / or adjustable lens disposed in front of the detector, a detector configured as a unit movable with respect to a lens disposed between the detector and the lens and the eye to be examined 108, or a movable or adjustable lens disposed between the eye to be examined 108 and the lens and the detector unit is included.

[0209] In some embodiments, the subjective examination optical subsystem defines an optical path including a subjective examination illumination unit 104 including a subjective examination beam source 210 and a combining and collimating optical system 212. The beam source 210 includes, for example, one or more laser diodes (e.g., edge emitters or VCSELs) that emit in the visible region (440 - 660 nm). Preferably, the beam source 210 includes at least three beam sources, namely, a red beam source (e.g., having a wavelength of about 620 nm - 660 nm), a green beam source (e.g., having a wavelength of about 500 nm - 540 nm), and a blue beam source (e.g., having a wavelength of about 440 nm - 470 nm). The combining and collimating optical system 212 includes, for example, one or more optical elements for combining the beams. For example, the combining and collimating optical system 212 includes one or more of the following. · An optical element that transmits or reflects light according to the wavelength of the light. · A diffractive optical element such as a diffractive beam combiner. · An optical waveguide on a photonic integrated circuit, for example.

[0210] The combination of the beams is performed before or after being collimated by one or more collimating lenses. When beams of multiple wavelengths travel together, it is preferable that those beams be combined so as to match their convergence as much as possible. The combining and collimating optical system 212 optionally includes a pinhole.

[0211] In some embodiments, for example, as described in connection with FIGS. 1A-2B, the cylindrical correction unit 214 (regardless of where it is disposed) corresponds to an arrangement of lenses operable to introduce a selected axis and refractive power of cylindrical optical correction into the beam subjective inspection illumination unit 104.

[0212] Alternatively, in some embodiments, one or more chambers are provided for the refractive powers of the plurality of cylindrical lenses introduced into the beam. Optionally, each of the plurality of chambers is selectable by rotation (or an exchange operation) and introduces the refractive powers of different cylindrical lenses. Additionally or alternatively, one or more of the chambers are provided with Jackson cross-cylindrical lenses that are adjustable relative to each other and can introduce ranges of various cylindrical lens powers. By selection and / or adjustment, the current optical refractive power that compensates for the subject's cylindrical error and axis error is set.

[0213] The position of the cylindrical correction unit 214 within the optical path does not necessarily have to be the same as the order shown with respect to the scanning unit 106, the subjective inspection relay optics 216, and / or the spherical correction unit 218. For example, as described for the spherical correction unit 218, generally, it may be rearranged to be disposed at the front and rear positions. In particular, disposing the cylindrical correction unit 214 behind the scanning unit 106 is a potential advantage to avoid complicating the cylindrical correction due to the wavefront effect caused by the change in the reflection angle from the mirror. This also applies to the correction unit 214, as shown and described, for example, in connection with FIGS. 9 and 12.

[0214] In some embodiments, the scanning unit 106 is shared between the subjective inspection optical subsystem and the objective inspection optical subsystem of the optical system 101.

[0215] The relay optical system 216 for subjective inspection has, for example, one or more lenses that relay the beam from the scanning unit 106 to a selected plane (e.g., the pupil of the eye to be examined) at a selected magnification. Alternatively, the beam is relayed at a selected magnification to an intermediate plane before being further relayed to the pupil of the subject.

[0216] In some embodiments, the spherical correction unit 218 is, for example, movable or an adjustable lens that moves along the optical axis of the laser beam from the subjective inspection illumination unit 104. It is shown to be disposed in the optical path after the relay optical system 216 for subjective inspection. Alternatively, it may be located between the beam source 210 and the scanning unit 106 (e.g., for the cylindrical correction unit 214). As another example, the spherical correction unit 218 may include one or more movable mirrors and / or lenses disposed between the lenses of the relay optical system 216 for subjective inspection.

[0217] In the shown position, the spherical correction unit 218 includes an optical system that directs light towards the binocular optical system 206. Within the binocular optical system 206, some elements are shared in common with the optical path of the objective inspection optical subsystem. For example, a beam combiner and / or a folding mirror may be shared. Other elements may have functions that are used only for one of the inspection functions, such as, for example, folding mirrors and / or lenses.

[0218] In some embodiments, along the optical path of the objective inspection optical subsystem, the beam emitted from the objective inspection beam source 200 is collimated and / or focused by the collimating and focusing optical system 202. This beam is then reflected by the scanning unit 106 and guided to the collimating optical system 204. This optical system, together with the scanning unit 106, controls, for example, the position of the beam and / or the collision angle with the eye 108 after the beam passes through the ophthalmic optical system 206. The light reflected from the layers of the subject's eye returns to the ophthalmic optical system 206 and is then reflected to the objective inspection detection unit 102. The reflected light reaching the objective inspection detection unit 102 contains refractive information from the eye under test 108 and is, for example, subject to further analysis according to methods of objective refractive measurement known in the prior art.

[0219] In some embodiments, along the optical path of the subjective inspection optical subsystem, one or more beams emitted from the subjective inspection beam source 210 are collimated and combined by the combining and collimating optical system 212. The one or more beams pass through the cylindrical correction unit 214 and are two-dimensionally scanned by the scanning unit 106. The cylindrical correction unit 214 does not necessarily have to be present at this position and may be arranged, for example, as an option immediately before or after the spherical correction unit 218 or at other positions after the scanning unit 106. The subjective inspection relay optical system 216 relays the scanned beam to a selected plane (e.g., the pupil of the subject). The scanned beam passes through the spherical correction unit 218 and the ophthalmic optical system 206. The scanned light is incident on the eye under test 108 and creates an image on the retina 110 of the eye under test. During the subjective visual acuity test, the visual appearance of the image is reported by the subject. The settings of the spherical correction unit 218 and / or the cylindrical correction unit 214 are adjusted to determine the settings that produce the best image based on the reported perception of the subject.

[0220] Referring to FIG. 9, a block diagram schematically shows an optical module of a modified example of a scanning system 101 having an operation unit 106 for two uses and combining an objective refractometry subsystem and a subjective refractometry subsystem according to some embodiments of the present disclosure. In some embodiments, the optical system 101 of FIG. 9 corresponds to a modification of the optical systems 101 of FIGS. 7 and 8. In particular (compared with FIG. 8), the displays of the relay optical system 302 for objective inspection and the beam splitting optical system 300 are shown. The modules added to FIG. 9 compared with FIG. 8 assist in supporting objective refractive error measurement based on the Scheiner principle (described in relation to FIGS. 10-11, for example). Also shown are boxed displays identifying an objective inspection optical subsystem (box 954), a subjective inspection optical subsystem (box 952), and a module common to each (box 956).

[0221] In some embodiments, the objective inspection optical subsystem of the optical system 101 includes an objective inspection illumination unit 100 including a beam source 200 and a collimating / condensing optical system 202. A scanning unit 106 is also included. The beam splitting optical system 300 includes one or more optical elements configured to separate the beam. The optical element is, for example, an optical element that transmits or reflects light according to the wavelength of the light. In some embodiments, such an optical element is configured to transmit IR light while reflecting shorter wavelength visible light. In some embodiments, the optical element has refractive properties sensitive to polarization. For example, it performs different refractions for s-polarized light and p-polarized light. In some embodiments, the beam splitting optical system includes a diffractive optical element (e.g., a diffractive beam splitter).

[0222] The relay optical system 302 for objective inspection includes, for example, two or more lenses that relay the beam from the scanning unit 106 to a selected surface, such as the cornea of the subject, the retina 110, or other selected surface, at a selected magnification. Also provided is a collimating optical system 204, a binocular optical system 206, and an objective inspection detection unit 102 configured to detect reflections from the eye under test 108.

[0223] In some embodiments, the subjective inspection optical subsystem of the optical system 101 includes a subjective inspection illumination unit 104 that includes a beam source 210 and a combining and collimating optical system 212. In some embodiments, a cylindrical correction unit 214 (which again need not necessarily be located at this position and can be located, for example, immediately before or after the spherical correction unit 218 or at other positions after the scanning unit 106), a scanning unit 106 (shared with the objective inspection optical subsystem), a beam splitting optical system 300 (similarly shared), a subjective inspection relay optical system 216, a spherical correction unit 218, and a binocular optical system 206 (again shared) are provided.

[0224] Some elements of the common module may be individually assigned only to one of the two inspection subsystems. For example, there may be a common beam combiner, or one or more lenses, folding mirrors, and other elements may be split.

[0225] In some embodiments, reference is made to FIG. 10, which is a schematic optical diagram of the objective inspection optical subsystem of the optical system 101 of FIG. 9.

[0226] In some embodiments, the beam source 200 emits a beam whose diameter is changed by the focusing optical system 202 and which is substantially focused on the scanning unit 106. The scanning unit 106 reflects the beam to an optional folding mirror 404 through lenses 400 and 402 that implement the objective inspection relay optical system 302 of FIG. 9 in FIG. 10. The beam passes through the beam splitting optical system 300.

[0227] The beam is implemented as an optionally movable lens, followed by a collimating optical system 204, to enable the use of the shiner principle described in connection with FIG. 11. The focal length of the collimating optical system 204 approximately matches the distance to the folding mirror 404. More generally, the focal length approximately matches the focal distance of the relay optical system 302 for objective inspection. This allows the beams reflected at different angles by the scanning unit 106 to return to propagate parallel to each other, although they are spatially at different positions.

[0228] The beam then passes through an ophthalmic optical system 206 comprising a beam splitter 406 and a beam combiner 408. The beam is incident on the eye under test 108 through the cornea 410 and the pupil 412. A part of the light reaching the retina 110 is reflected from the retina 110 to the pupil 412 and the cornea 410.

[0229] The reflected beam continues to pass through the beam combiner 408 and reaches the beam splitter 406. The beam splitter 406 reflects the light to an objective inspection detection unit 102 comprising a lens 414 and a detector 416. When the light reflected from the retina 110 reaches the objective inspection detection unit 102, the light contains refractive information from the eye under test 108, and this information is analyzed according to the shiner principle (as described next).

[0230] FIG. 11 is a schematic optical diagram of the shiner principle, for example, implemented using the optical arrangement of FIG. 10, in some embodiments of the present disclosure.

[0231] The state where three pairs of laser beams 415 - 417 are incident on the eye under test 108 from the left side is shown. Each pair of beams is parallel to each other, but each pair of beams is incident on the eye under test 108 at (slightly) different angles. During operation, each pair represents, for example, different positions of the lens 204, and the lens 204 moves to change the convergence of the beam. Also, there are multiple (e.g., at least three) positions where the beam enters the eye (e.g., positions at different meridians of the eye), and these beams may be presented to each other simultaneously.

[0232] Near the retina, the intersection position of each beam pair depends on the incident angle of the beam pair and is modified by the magnification of the anterior part of the eye (e.g., the lens and the cornea) such that the beam pair passes through the pupil 412.

[0233] By controlling the beam source 200 and the scanning unit 106 in correlation with the adjustment of the collimating optics 204, both the incident angle and the position of the beam pair with respect to the eye under test 108 can be controlled. With appropriate adjustment, the intersection of each pair is accurately performed on the retina 110. This state can be detected by imaging the retina on the detector 416. The detector can be adjusted to move with the lens 414 if there is another lens between the lens 414 and the eye under test 108. Alternatively, the lens 414 can be moved relative to the detector 416 to compensate for the refractive error of the eye under test 108. The positions of the collimating optics 204 and the scanning unit 106 when the eye under test 108 is illuminated focusally by the beam source 200 correspond to a certain refractive error of the eye under test 108 when the beam is irradiated at a specific position of the eye under test 108. By appropriately selecting a plurality of positions on the anterior part of the eye under test 108 where the beam is received, the values of the spherical refractive power, the cylindrical refractive power, and the axis diopter of the eye under test 108 can be derived.

[0234] During objective measurement, the subject is recommended to focus distally while maintaining a relatively weak accommodation. The subject is instructed, for example, to direct attention to a target (e.g., a blurred image) that is perceptually felt to be far away, and accordingly urged to adjust the eye's crystalline lens. In some embodiments, the target is created by a retinal scanning display system that is also used as a subjective examination optical subsystem for subjective visual acuity testing.

[0235] FIG. 12 is a schematic optical diagram of a subjective examination optical subsystem according to some embodiments of the present disclosure. In some embodiments, the arrangement of FIG. 12 corresponds to the elements of blocks 952 and 956 of FIG. 9.

[0236] The beam source 210 emits one or more beams that pass through, for example, a coupling and collimating optical system 212 and a cylindrical correction unit 214 disposed in the corresponding gray area. Also, the cylindrical correction unit 214 (the structure corresponding to the cylindrical correction unit 214) may be disposed at other positions in the optical path, for example, immediately before or after the spherical correction unit 218. In some embodiments, this corresponds to either the cylindrical arrangement or the axis correction arrangement described in connection with FIGS. 1A - 2B.

[0237] In some embodiments, one or more beams are reflected from the scanning unit 106 to the beam splitter 300 via the relay lens 400. These elements may be used in common with an objective inspection optical subsystem such as that shown in FIG. 10. In the beam splitting optical system 300, the objective inspection illumination beam and the subjective inspection illumination beam are split (for example, the subjective illumination is reflected and, in FIG. 10, the objective illumination is transmitted).

[0238] One or more beams pass through the spherical correction unit 218 (for example, disposed in the corresponding gray area) and through another relay lens 500.

[0239] As shown in the figure, the subjective inspection relay optical system 216 includes relay lenses 400 and 500 that relay one or more beams to the pupil 412 of the subject.

[0240] After the relay lens 500, one or more beams are directed toward the eye under test 108 by the ophthalmic optical system 206. As shown in the figure, the ophthalmic optical system 206 includes a folding mirror 502 and a beam combiner 408 (also shown in FIG. 10). One or more beams pass through the cornea 410 and the pupil 412 and subsequently reach the retina 110, where an image is generated on the retina 110.

[0241] FIG. 13 is a schematic optical diagram of the objective inspection optical subsystem and the subjective inspection optical subsystem of the optical system 101 according to some embodiments of the present disclosure. In some embodiments, the arrangement of FIG. 13 corresponds to many of the elements of FIGS. 10 and 12. The objective inspection illumination beam and the subjective inspection illumination beam are shown to be already combined with each other (by additional elements not shown) before being reflected at the same angle by the scanning unit 106.

[0242] The beam combining optical element includes an element that transmits or reflects light according to the wavelength of the light, a diffractive optical element (e.g., a diffractive beam combiner), and an optical waveguide on a photonic integrated circuit. The combination of the beams may be performed after being collimated by one or more collimating lenses. Alternatively, the beams are incident on the scanning unit 106 at different angles, and the spatial relationship of the components along the rest of the optical path is appropriately adjusted for the difference.

[0243] As shown, the reflected beams from the scanning unit 106 for objective measurement and subjective measurement reach the lens 400 and are separated by the beam splitting optical system 300. The beam for objective measurement passes through the objective inspection relay optical system 302 including the lens 402 and the lens 400. The beam is then reflected by the folding mirror 404 through the collimating optical system 204, passes through the beam splitter 406, and passes through the beam combiner 408. The beam combiner 408 directs the beams used for objective measurement and subjective measurement toward the eye under test 108. The reflected light from the eye under test 108 passes through the beam combiner 408, is reflected by the beam splitter 406 to the detection unit 102, and the reflected light is analyzed in the detection unit 102.

[0244] Along the subjective illumination optical path, the relay optical system 400 functions as the proximal relay lens of the subjective inspection relay optical system 216. The beam is separated from the objective inspection illumination beam by the beam splitting optical system 300 (e.g., reflection). The beam passes through the spherical correction unit 218 (e.g., arranged in the corresponding gray area) and reaches the distal relay lens 500 of the subjective inspection relay optical system 216, from where it is relayed to the pupil 412 of the subject. The relay eye 108 passes through the ophthalmic optical system 206 including the folding mirror 502 and the beam combiner 408. The beam is incident on the eye under test 108 and reaches the retina 110 to generate an image.

[0245] Optionally, the optical system 101 of FIGS. 9-10 and 12-13 includes a keratometry unit 112. The keratometry unit 112 is configured to measure the corneal shape of the eye under test. This enables additional information and / or verification regarding the optical function of the eye under test 108. For example, information regarding astigmatism, astigmatic axis, total corneal refractive power, and / or radius of curvature of the cornea is included.

[0246] Arrangement of the dual scanning unit FIG. 14 is a schematic optical diagram of the combined objective inspection optical subsystem and subjective inspection optical subsystem of the optical system 101 using two scanning units 702, 708 according to some embodiments of the present disclosure. Each scanning unit 702, 708 scans in one dimension. They are arranged so as to be able to perform two-dimensional scanning.

[0247] The combined beam 700 of the objective optical subsystem and the subjective optical subsystem is irradiated onto the first scanning unit 702 and relayed to the second scanning unit 708 via lenses 704 and 706. The combination of the beams is not shown. The beam follows lens 400 and reaches the eye under test 108 through an arrangement of elements corresponding to the arrangements of FIGS. 9 - 10 and / or FIGS. 12 - 13, for example.

[0248] The relay between the two scanning units 702 and 708 shown by the two lenses is optionally implemented by any suitable number of lenses. Optionally, there is no relay component located between scanning units 702 and 708.

[0249] Objective optical inspection by ray - tracing aberration measurement FIG. 15 is a schematic optical diagram of a combination of an objective inspection optical subsystem and a subjective inspection optical subsystem of an optical system 101 according to some embodiments of the present disclosure. The objective inspection optical subsystem uses ray - tracing aberration measurement. The objective inspection illumination beam and the subjective inspection illumination beam are shown as being previously combined (by additional elements not shown) before being reflected by the scanning unit 106 at an angle selected for each inspection.

[0250] Regarding the beam used in the objective inspection measurement, the combined beam 700 is incident on the scanning unit 106 and may be divergent, convergent, or parallel internally when it is incident. For example, it may be focused or substantially focused when it impinges on the scanning unit 106.

[0251] Examples of beam combining optical elements include elements that transmit or reflect light according to the wavelength of the light, diffractive optical elements such as diffractive beam combiners, and the like. Alternatively, an optical waveguide can be formed, for example, on a photonic integrated circuit. The beam combination may be performed after collimation by one or more collimating lenses.

[0252] The scanning unit 106 reflects the beam to the beam splitting optical system 300, thereby separating the beam into an objective inspection illumination beam and the beam of the subjective focus target illumination pathway and / or the objective focus target illumination pathway.

[0253] The beam for objective measurement passes through the objective relay optical system 302 (FIG. 9) including the lens 402 and the lens 400 as shown in FIG. 15. In some embodiments, the beam is reflected from the folding mirror 404. The collimating optical system 204 is shown as a fixed lens, but optionally may include one or more fixed, movable, and / or adjustable lenses.

[0254] The beams reflected from the scanning unit 106 at different angles are spatially at different positions but propagate parallel to each other. The beams pass through the beam splitter 406 and the beam combiner 408, pass through the cornea 410 and the pupil 412, and enter the eye under test 108. The beams reach the retina 110, are reflected from the retina 110, and return to the pupil 412 and the cornea 410. The reflected light passes through the beam combiner 408 and is then reflected by the beam splitter 406 to the lens 800 and directed to the detector 802.

[0255] The beam splitter 406, beam combiner 408, lens 800, and detector 802 are fixed relative to each other but are movable together or are provided together with another lens that is movable to correct refractive errors. The detector 802 is implemented using, for example, a photosensor, quadrant photodetector, CCD camera, position sensitive detector (PSD), and / or other photosensors.

[0256] The reflected light from the retina 110 that reaches the detector 802 contains refractive information from the eye under test 108. Different beams resulting from different angles of the scanning unit 106 are shown. When reaching the eye under test 108, all the beams are parallel to each other but enter the eye under test 108 at different positions. By controlling the beam source 200 (which contributes to the combined beam 700) and the scanning unit 106, the position where the eye under test 108 is irradiated with the beam can be sequentially changed. The detector 802 measures, by retroreflected light, the exact position where each beam reaches the retina 110. This process is continued until several separation points are projected onto the entrance pupil 412. In this way, a correlation with the directions taken when the light rays enter and exit is obtained, enabling the reconstruction of the actual wavefront error. From such data, the values of the spherical refractive power, cylindrical refractive power, axis number, and corneal curvature of the eye under test 108 can be derived. The subjective vision examination subsystem is optionally configured as described, for example, with respect to the embodiments of FIGS. 12 - 14.

[0257] Arrangement of the dual scanning unit In some embodiments, the general arrangement of FIG. 15 is modified by combining it with the dual scanning unit arrangement described in relation to FIG. 14. As described above, each scanning unit scans in one dimension, and by combining them, two - dimensional scanning can be performed.

[0258] Examination of vision and / or refractive error For use in subjective vision testing, the image formed by the beam scanned on the retina 110 may be, for example, a visual acuity chart such as a Snellen chart, a Landolt ring chart, a tumbling E chart, a Lea test, a HOTV chart, a clock dial chart, a sinus chart, a spatial frequency chart (e.g., EIA resolution chart 1956, ISO 12233, USAF 1951), etc., and / or other images for evaluating the refractive error of the subject. Optionally, 3D and / or binocular presentation functions are used to present the visual test image so as to appear to be localized three-dimensionally or in the depth direction. For example, depth cues can be used to change the apparent size and distance of the stimulus. Optionally, this can be done while maintaining the same angular size. This can, for example, assist in the control of accommodation. Optionally, stimuli associated with different depths (i.e., different depth cues) are presented simultaneously to obtain a stereoscopic appearance of the test image.

[0259] As a starting point for subjective testing, different information can be used for shaping the beamforming in the initial image. For example, the subject's last prescription, or the subject's glasses can be measured, or the values previously obtained in an objective vision test can be used. Initial values of spherical power, cylindrical power, and / or axis direction are used to shape the scanning laser beam that generates the image. The values used as the starting point can be used as the initially acquired values, or can also be used together with added or subtracted coefficients (e.g., calibration coefficients, which can be determined empirically).

[0260] Based on the input from the subject, the spherical power, cylindrical power, and axis direction are adjusted, and the parameters for generating an image on the subject's retina 110 are reported to be optimal by the subject.

[0261] Using changes in the shape of the beam (corresponding to divergence, convergence, astigmatism and astigmatic axis, spherical refractive power, cylindrical refractive power, and cylindrical axis), an image optimized for the retina 110 of the subject is generated, and based on these changes, subjective values regarding the spherical refractive power, cylindrical refractive power, and refractive error of the axis of the subject are derived. Following the subjective visual acuity test, a complete eyeglass prescription can be created.

[0262] FIG. 16 is a schematic flowchart of a method for measuring the refractive error of an eye under examination and providing a prescription for glasses or contact lenses according to some embodiments of the present disclosure. The examiner, the subject himself / herself, or a designated person can perform and / or supervise the operations of each block, and it can be performed remotely as an option. In some embodiments, a computer processor is used to operate aspects of the device's functionality. For example, it is operated in response to sensed information, in response to commands input remotely or locally, or according to one or more internally defined protocols.

[0263] In block 900, in some embodiments, the subject is optionally requested to enter (or otherwise provide) personal information and related known eye medical history. In some embodiments, in block 902, the subject's eye is correctly aligned with the device. This is described in detail, for example, in relation to FIG. 17.

[0264] Briefly referring to FIG. 17, FIG. 17 is a schematic flowchart of a method for aligning an eye under examination with an optical system 101 according to some embodiments of the present disclosure.

[0265] In some embodiments, in block 1000, the subject inserts his / her head into the mount. In some embodiments, this includes a chin rest, a forehead rest, and / or a cheekbone rest, or other mechanical arrangements for fixing the subject in a certain position.

[0266] In block 1002, in some embodiments, for example, a coarse alignment process is executed until a camera located within the device can recognize and position the pupil of the subject with respect to the device. This process can be executed manually (e.g., the position adjustment is done by hand) and / or can be automatically executed under the control of a processor (e.g., the adjustment is done using an actuator and monitors the monocular and / or binocular eye alignment (e.g., pupil alignment) inside and outside the device under feedback control from a controller that monitors camera images and other sensor data).

[0267] In block 1004, in some embodiments, for example, after sensing recognizes the pupil position of the subject, a fine adjustment process is initiated (e.g., by further motor operation, optionally under control based on feedback from an image or other sensors by the processor). Thereby, for example, the pupil will be in the correct position with respect to the optical axis of the optical device up to 6 axes (x, y, z, roll, pitch, yaw). Optionally, pitch and / or yaw adjustment is omitted. Optionally, roll is omitted. Optionally, one or two of the displacement axes are omitted or manually controlled.

[0268] In block 1006, in some embodiments, confirmation of positioning options is provided via an image marked with a boundary projected onto the eye that indicates the angle at which the projected beam enters the pupil 412 of the subject, based on input from the subject. These can be used to define the field of view (FOV) of the subject. Optionally, the FOV is determined automatically (e.g., by imaging the retina). Optionally, ensure an appropriate FOV depending on the fine adjustment process of block 1004, or assume that the FOV is appropriately positioned as a result of other arrangements.

[0269] From block 1008, in some embodiments, the ophthalmic examination can be performed on both eyes together or alternately.

[0270] Returning to FIG. 16, a first examination is initiated on the corrected and positioned subject.

[0271] In block 904, in some embodiments, the subject's accommodation is optionally analyzed. The analysis may be based on an initial trial of an objective examination, eye tracking, or other forms of electronic sensing. This result can assist, for example, a processor in determining a device setting that can correct imperfect accommodation, such as variations in spherical correction for a focused image. Optionally, additional measures are taken to promote accommodation, such as presenting an object in a scene visualized by transmission beyond the test optics itself, an image sequence presented to draw the subject's attention (e.g., an image sequence presented via the illumination optical path for a subjective examination), or other methods. The initiation of such measures is optionally proposed to the user interface by an output from the processor or executed by the processor.

[0272] In block 906, in some embodiments, an objective refractive error test is performed. Optionally, the operations of blocks 904 and 906 are performed iteratively together as test results are obtained, for example. The test is optionally performed while the subject views a target (usually a blurred image, or an image including a blurred portion and a portion presented in sharp focus) created by an optical path used to perform a subjective vision test (e.g., used later or simultaneously). In some embodiments, the objective refractive error test is performed simultaneously for binocular vision. In some embodiments, the test device includes a moving element that operates to adjust the relative angle of a projection system that presents an image to either of the eyes during the vision test. This adjustment can be used to change the apparent distance of the target presented for binocular vision. As the subject accommodates, changes can occur in the eye's convergence and the accommodation of the lens. For example, the accommodation of the lens can be drawn to a distant focus. The accompanying change in the eye's convergence can also change the angle of the subject's eyes. In some embodiments, adjusting the relative angle between the projection systems also adjusts the angle of the optical path that projects the objective test light pattern onto the retina, thereby maintaining angular alignment with respect to the eye. The adjustment is optionally performed under the control of a protocol of a processor or when detection of the position and / or condition of the subject's eye (e.g., pupil size, fixation stability, or accommodation) is sensed.

[0273] In some embodiments, an objective test (e.g., an objective test based on infrared illumination) is performed at least partially simultaneously with other tests, such as the subjective test measurements of blocks 910-912. Performing the tests simultaneously can save time or provide an opportunity to improve the objective test results when the subject focuses at different distances during the subjective test. This can occur, for example, as a result of the target being presented more clearly when the optical correction used in the subjective test changes. In some embodiments, the subjective test image itself is used as the target for the objective test. For example, the target is presented in depth (and optionally "swept" in depth, e.g., moved from an apparent foreground to an apparent distance during a transition phase of the test) to assist in setting the appropriate focus for the ongoing objective test. Such modification of the subjective test image is optionally performed by a processor as part of a predetermined protocol or in response to sensing the state of the subject's eye.

[0274] In block 908, in some embodiments, keratometry is optionally performed. Keratometry is performed depending on whether an optical system (e.g., an optical system described in connection with FIGS. 6 and 7 and optionally provided together in any of the embodiments of the optical system 101 described herein) configured to perform this test is present.

[0275] Starting from block 910, in some embodiments, subjective measurements include one or both of a distance vision test (including a test for astigmatism) in block 910 and a near vision test in block 912, and are performed optionally.

[0276] In some embodiments, the examination utilizes binocular examination target presentation capabilities to assist in the examination. In some embodiments, the subjective examination includes switching at least a portion of the presented target between the eyes or presenting different portions of the target to different eyes. The subject can be asked (optionally prompted by the device itself) to actually evaluate which eye is seeing the target more clearly. For example, the subject can be asked when they see the target most clearly or which part of the target they see most clearly. In some embodiments, the response is provided directly to the device itself or measured by the device. In some embodiments, the processor determines how to change the optics of the device according to a protocol based on the received input, and for example, the change is made to correct for spherical aberration and / or cylindrical aberration of the subject's eyes. In some embodiments, the targets presented to each eye are made clear enough (e.g., stripe patterns in different directions) such that their separate adjustments can be (potentially) clearly perceived and reported.

[0277] In some embodiments, the optical refractive power of the examination (cylindrical refractive power and / or spherical refractive power) varies through a range at a relatively fast rate (e.g., faster than the subject can react before the state changes), and the subject is instructed to signal when seeing a certain clarity and / or consistency state. There may be a lag in the subject's response, but since the refractive power variation can approach the signaled state from both sides, the lag phase can be estimated (e.g., by a processor, for example, by averaging the response phases), which helps determine the instant when the perceptual state is signaled. This can potentially improve the speed of the examination process and also enable the evaluation of more or more densely sampled optical correction conditions. Optionally, the speed of variation is appropriately adjusted according to the subject's response performance, for example, adjusted to maintain a moderately consistent response. When executed more slowly, the variation may help determine accommodation hysteresis (e.g., the difference in eye accommodation depending on whether the optical correction power is increasing or decreasing). Adaptation to the patient's performance may be automatically performed by a processor based on the patient's performance characteristics, such as response consistency and hesitation.

[0278] Perceptual simultaneity is not necessarily used. For example, the cylindrical refractive power can be evaluated by movement with a relatively slow oscillation speed of the cylindrical lens arrangement, e.g., oscillation below 1 Hz. The displayed pattern may be shown to the subject to move (optionally smoothly) downward across, around, or in other ways through the display area. The subject may be instructed to look for (and optionally view) the most distinct area. These may be reported (e.g., listing the number or other label closest to that area or describing it), or the eye position itself can be used as an indicator of where the best optical clarity is recognized.

[0279] In some embodiments, eye movements (e.g., eye movements measured by a gaze detector within the device) drive the presentation of stimuli and the configuration of the optical system. For example, the cylindrical refractive power, the cylindrical axis, and the spherical refractive power can be mapped through positions on the display. As the subject looks across the display area, the optical system is adjusted to match the mapping. The area to which the subject's gaze is attracted and / or fixed is selected, for example optionally, as a criterion for further examination and selection after remapping. The remapping can be continuous, for example, such that the mapping "scrolls" (in some cases more stepwise) in a particular direction as the eye moves to find the area where it focuses on the target. Thereby, the eye is drawn back to the center of the display area. Optionally, the optical task is changed during the examination, for example, to reduce the subject's fatigue, by changing the way the display area is divided between optical settings, or by changing the shape or color of different targets, or the pattern of target movement.

[0280] In some embodiments, fluctuations in intensity in subjective examination illumination are used, at least in a portion of the subject's visual field, for example near the fovea, to assist in evaluating the subject's visual field capabilities. For example, the subject may be asked to evaluate / indicate when two illumination areas match or when the intensity is visually different, the location and timing at which the subject can recognize a change in illumination intensity, the location and timing at which the subject can recognize a gradient of illumination, or the location / timing at which other criteria are met.

[0281] In some embodiments, the subject is given at least partial control over visual stimuli and / or optical correction power, enabling the subject to manually select the conditions under which certain subjective recognition criteria are met. Optionally, the selection is repeated from different initial conditions or from different available ranges. For example, the subject may turn a knob (or control another selector) to select the orientation of the cylindrical correction that results in the maximum or minimum distortion (e.g., the clearest separation of two adjacent lines or points), and / or select the degrees of cylindrical and spherical correction that result in the minimum distortion, a matching distortion between the two eyes, or select according to other criteria.

[0282] In block 914, in some embodiments, a prescription for refractive corrective glasses and / or contact lenses is optionally prescribed.

[0283] Referring to FIG. 18, a compact vision and / or refractive error inspection system 1701 in some embodiments is shown. Further, referring to FIGS. 19A - 19B, FIGS. 19A - 19B schematically show the desktop use of a compact vision inspection kit 1701 for performing a vision test on a subject, according to some embodiments of the present disclosure.

[0284] In some embodiments (e.g., as shown in FIG. 18), the vision and / or refractive error inspection system 1701 includes a controller 1100, a vision measurement device 1102, and a mechanical head positioning unit 1104. The vision measurement device 1102 is approximately the width of the head, and has a depth and height slightly smaller, but can be of any size suitable for housing the inspection optical system, for example, with a maximum dimension of 20 - 50 cm. The inspection optical system can be binocular optionally, or monocular optionally.

[0285] As an option, the mechanical connector unit 1106 is configured to support the vision measurement device 1102 above a surface such as a tabletop. As an option, the mechanical connector unit 1106 is a stand-alone type (for example, as shown in FIG. 19A). As an option, the mechanical connector unit is attached to the mechanical head positioning unit 1104, as shown in FIG. 19B.

[0286] The schematic diagram of FIG. 18 shows that the vision and / or refractive error inspection system 1701 can be housed and / or transported as a handheld unit, for example, housed in a latch case 1116, which is provided with a case bottom 1116B, a lid 1116C, and a handle 1116A. The case 1116 may provide internal support (such as foam or straps, etc.) for safely holding the system elements in position (not shown).

[0287] The vision measurement device 1102 is constructed based on, for example, the principles and design elements described in connection with other embodiments of this specification (for example, the forms of FIGS. 7-15 that operate according to either of the methods of FIGS. 16 and 17 as an option), and may include, as an option, a vision measurement device and / or a refractive error measurement device having functions (such as a cylindrical correction function, etc.) described in connection with any of FIGS. 1A-6.

[0288] In some embodiments, the controller 1100 includes an input controller 1100A (FIG. 19A) for the examiner 1108 to operate the system, and a display unit 1100B for the examiner 1108 to observe images, data, procedures, and other information for performing the vision examination. As an option, the examiner 1108 exists, for example, at an off-site location via a telecommunication connection. As an option, a technician assists in positioning the subject, and the examiner 1108 performs the examination itself. The arrangement of the examiner (examination supervisor) and the technician (assistant) may correspond to, for example, that described with respect to FIGS. 5 and 16.

[0289] As an option, functions for input control and display are combined, for example, as a controller 1100 with a touch screen (Figs. 18 and 19B).

[0290] To perform a vision test, the vision measuring device 1102 is aligned with a mechanical head positioning unit 1104. The mechanical head positioning unit 1104 serves to hold the head 1110 of the subject in a fixed position. For example, a chin rest 1104B (optionally, a height-adjustable chin rest), a forehead strap 1104C, and / or other elements that contact the subject's head to assist in maintaining the position. In particular, the head positioning unit 1104 helps to keep the eyes 108 of the subject's head 1110 in a fixed position during the examination.

[0291] In some embodiments, any mechanical connector unit 1106 supports the vision measuring device 1102 at an appropriate position relative to the head positioning unit 1104. The mechanical connector unit may be self-standing, may be connected to the head positioning unit 1104 (e.g., via a clamp 1104A), or may be configured to connect or stabilize the device. For example, it may be connected to a table 1109 or other surface. As an option, spatial adjustment (e.g., movement in the X, Y, and / or Z directions) is provided, thereby adjusting the position of the subject 1110 within the head positioning unit 1104, the position of the vision measuring device 1102 held by the mechanical connector unit 1106, or the clamp position relative to the table 1109.

[0292] Referring briefly to Fig. 19C, a refractive error inspection system 1701 installed on a kiosk stand 1901 is schematically shown. In some embodiments, this device is operated as part of a kiosk that provides glasses or vision testing services. For example, it is provided in a shopping mall or other commercial (e.g., consumer retail) activity location.

[0293] For example, in some embodiments, the kiosk is located as part of an open retail space, for example, at least two meters away from a wall, with two or more sides open to pedestrian traffic, and / or away from a wall.

[0294] In some embodiments, the kiosk includes one or more display cabinets. In some embodiments, the kiosk includes a countertop. Optionally, the inspection system 1701 is accessible to the subject at the countertop. Optionally, the inspection system 1701 is accessible to the subject within a space surrounded by a countertop, one or more display cabinets, or any combination thereof.

[0295] In some embodiments, the subject places an order for corrective optics based on a lens prescription obtained through the operation of the inspection system 1701, and the order includes one or more articles (e.g., eyeglass frames or parts thereof, cases, or care accessories) directly displayed and / or illustrated on a display at the kiosk.

[0296] Referring to FIGS. 20A - 20C, head - mounted embodiments of a vision inspection system according to some embodiments of the present disclosure are schematically shown. FIGS. 20A - 20B show embodiments that are worn on the head, where the optical system of the inspection system is housed within a housing fixed to the head by a strap. FIG. 20C shows a more compact embodiment as glasses or goggles. In either case, the optical system is optically provided together with other suitable kit elements, for example, including a carry - case 1116, a controller 1100, and / or a cable 1103.

[0297] General Matters During the life of the patent maturing from this application, many related image display types and / or adaptive lens types are expected to be developed. The scope of the terms "display" and "adaptive lens" is intended to pre - include all new technologies.

[0298] As used herein, "about" in relation to a quantity or value means "within ±10%".

[0299] The terms "comprises", "comprising", "includes", "including", "having", and their conjugations mean "including but not limited to".

[0300] The term "consisting of" means "including and limited to".

[0301] The term "consisting essentially of" means that a composition, method, or structure may include additional components, steps, and / or parts, provided that such additional components, steps, and / or parts do not substantially alter the basic and novel characteristics of the composition, method, or structure recited in the claims.

[0302] As used herein, the singular forms "a", "an", and "the" are intended to include the plural as well, unless the context clearly indicates otherwise. For example, "a compound" or "at least one compound" includes a plurality of compounds and may also include mixtures thereof.

[0303] As used herein, the terms "example" and "exemplary" are used to mean "an example, instance, or serving as an illustration". Embodiments described as "examples" or "exemplifications" are not necessarily to be construed as preferred or advantageous over other embodiments, and / or do not necessarily exclude the incorporation of features of other embodiments.

[0304] "Optionally" is used herein to mean "provided in some embodiments and not provided in other embodiments". Any particular embodiment of the present disclosure may include a plurality of "optional" features, unless such features are mutually exclusive.

[0305] As used herein, the term "method" means a manner, means, technique and procedure for achieving a given objective, including but not limited to those known to, or readily developed by, persons skilled in the fields of chemistry, pharmacology, biology, biochemistry and medicine.

[0306] As used herein, the term "treating" includes preventing the progression of a condition, substantially inhibiting, retarding or reversing the condition, substantially relieving the clinical or aesthetic symptoms of the condition, or substantially preventing the worsening of the clinical or aesthetic symptoms of the condition.

[0307] Throughout this application, various embodiments may be presented in a range format. It should be understood that the description in range format is merely for convenience and brevity and is not to be construed as a limitation on the flexibility of the description of the present disclosure. Accordingly, a description of a range should be considered to have specifically disclosed all the sub-ranges within the possible range, as well as the individual numerical values within that range. For example, a description of a range such as 1 to 6 should be considered to specifically disclose not only the sub-ranges such as 1 to 3, 1 to 4, 1 to 5, 2 to 4, 2 to 6, 3 to 6, etc., but also the individual numerical values within that range, such as 1, 2, 3, 4, 5 and 6. This applies regardless of the size of the range.

[0308] When a numerical range is recited herein (e.g., “10-15,” “10~15,” or any combination of numbers joined by any other indication of a range), unless used in a context clearly different in meaning, it is intended to include any number (fractional or integral) within the limits of the recited range. The expression “range between” the first recited number and the second recited number, and the expressions “range from” the first recited number “to” the second recited number, “range up to,” “range through,” or “range including” (or other terms indicating a similar range) are used interchangeably herein and are meant to include the first and second recited numbers, and all fractions and integers therebetween.

[0309] Although the present disclosure has been described in connection with specific embodiments thereof, numerous alternatives, modifications, and variations will be apparent to those skilled in the art. Accordingly, all such alternatives, modifications, and variations are intended to be included within the spirit and broad scope of the appended claims.

[0310] It should be understood that certain features of the present disclosure that have been described in connection with separate embodiments may also be provided in combination in one embodiment. Conversely, various features of the present disclosure that have been described in connection with one embodiment may also be provided separately, or in any suitable partial combination, or in relation to any other described embodiment. A given feature described in connection with various embodiments should not be construed as an essential requirement of that embodiment unless the embodiment would be inoperable without that element.

[0311] It is the applicant's intention that all publications, patents, and patent applications mentioned in this specification be incorporated herein by reference in their entirety to the same extent as if each individual publication, patent, and patent application were specifically and individually incorporated by reference herein. In addition, any citation or identification of a reference in this application should not be construed as an admission that such reference can be used as prior art to this disclosure. Also, to the extent that section headings are used, they should not necessarily be construed as limiting. In addition, if there are priority documents for this application, they are incorporated herein by reference in their entirety.

Claims

1. An optical path configured to project an image onto the retina of the eye, comprising a cylindrical lens that introduces a variable cylindrical optical refractive power and a variable cylindrical optical axis into a beam incident on the retina to generate the image, The cylindrical lens comprises a first cylindrical correcting lens group and a second cylindrical correcting lens group, each containing at least one cylindrical lens. The first cylindrical correction lens group and the second cylindrical correction lens group are Having cylindrical optical refractive powers of opposite signs, The first cylindrical correction lens group and the second cylindrical correction lens group are adjusted together to introduce the variable cylindrical optical axis while maintaining a predetermined relative alignment of their respective cylindrical axes. The variable cylindrical optical refractive power is adjusted by changing the distance between them. Image display device.

2. The first cylindrical correction lens group and the second cylindrical correction lens group rotate together around the optical axis of the optical path to introduce the variable cylindrical optical axis. The image display device according to claim 1.

3. The first cylindrical correction lens group corresponds to the first cylindrical refractive power axis, the second cylindrical correction lens group corresponds to the second cylindrical refractive power axis, and the relative alignment of the first cylindrical refractive power axis and the second cylindrical refractive power axis is within 5° of each other. The image display device according to claim 2.

4. The first cylindrical correction lens group and the second cylindrical correction lens group are arranged to maintain a common cylindrical axis during rotation of the optical path around the optical axis. The image display device according to claim 2.

5. At least the second cylindrical correction lens group comprises a plurality of cylindrical lenses, The cylindrical optical refractive powers of the plurality of cylindrical lenses are coupled along the optical path to generate a cylindrical optical refractive power with the opposite sign to that of the first cylindrical correcting lens group. The image display device according to claim 1.

6. The second cylindrical correction lens group comprises at least one lens on each side of at least one lens of the first cylindrical correction lens group. The image display device according to claim 1.

7. The at least one lens of the first cylindrical correcting lens group is movable between the at least one lens of the second cylindrical correcting lens group, located on each side of the at least one lens along the optical axis of the optical path, in order to introduce the variable cylindrical optical refractive power. The image display device according to claim 6.

8. At least one lens of the second cylindrical correction lens group moves along the optical path to change the introduced cylindrical optical refractive power, and there exists at least one position of the at least one lens of the second cylindrical correction lens group that cancels out the cylindrical optical refractive power of the first cylindrical correction lens group. The image display device according to claim 1.

9. The first cylindrical correction lens group and the second cylindrical correction lens group are located within the telecentric region of the beam. The image display device according to claim 1.

10. The beam as a whole has an envelope diameter and individually forms an image at the focal point on the retina. The envelope diameter of the beam is substantially constant between the first cylindrical correction lens group and the second cylindrical correction lens group. The image display device according to claim 1.

11. The first cylindrical correction lens group and the second cylindrical correction lens group change the cylindrical correction force by adjusting the distance between them, within a range of at least 4 diopters. The image display device according to claim 1.

12. The image display device has an optical pupil for the eye, which has a first diameter in the direction that is most affected by the variable cylindrical optical refractive power, and a second diameter perpendicular to the first diameter. The ratio of the first diameter to the second diameter is maintained at less than 2 over an adjustment range of at least 4 diopters. The image display device according to claim 1.

13. The display lighting that generates the aforementioned image comprises at least one of the group consisting of a μLED display, a μOLED display, an LED display, an OLED display, a QDLED display, an LCD display, an LCOS source, a DLP source, and a scanning beam source. The image display device according to claim 1.

14. An eye examination apparatus comprising an image display device according to any one of claims 1 to 13, The optical path of the image display device is configured to project a subjective refractive error image onto the retina. Eye examination device.

15. The optical path is further configured to project an objective refractive test pattern onto the retina, and the eye examination device includes a sensor that detects light returning from the retina based on the objective refractive test pattern. The eye examination apparatus according to claim 14.

16. An ophthalmic examination system configured to perform both subjective and objective refraction tests, The subjective refraction test and the objective refraction test include projecting images and test patterns onto at least a first retina of the subject during the test, The aforementioned eye examination system is The eye examination device according to claim 14, The system comprises a second optical path configured to project an objective refractive error pattern onto the first retina and including a sensor that detects light returning from the first retina based on the objective refractive error pattern, The optical path of the eye examination device projects a target image onto the first retina as a target for the subject to fixate on their vision and / or relax their accommodation, while the second optical path is operating to project the objective refraction test pattern. Eye examination system.

17. The eye examination device includes a third optical path configured to merge the subject's field of vision of the surrounding environment with either the image or examination pattern from the optical path or the second optical path. The eye examination system according to claim 16.

18. One or more of the optical paths of the image display device configured to project a subjective refractive test image onto the subject's retina, and the second optical paths configured to project an objective refractive test pattern onto the subject's retina, are replicated to produce binocularly aligned images on each of the subject's retinas in order to produce an image that is perceptually integrated for the subject. A series of images are presented to the subject to relax visual accommodation for near and far distances. The eye examination system according to claim 16.

19. An image display device comprising an optical path configured to project an image onto the retina of the eye, The aforementioned optical path is A first cylindrical correcting lens group comprising one or more self-adjustable cylindrical lenses having a first cylindrical axis and a first cylindrical optical refractive power, wherein the one or more self-adjustable cylindrical lenses are configured to change their refractive power to introduce a variable net cylindrical optical refractive power into the beam passing through the optical path, A second cylindrical correcting lens group comprising a second cylindrical axis having a second cylindrical axis whose relative alignment with the first cylindrical axis is maintained, and which comprises at least one cylindrical lens having a cylindrical optical refractive power opposite in sign to the first cylindrical optical refractive power, The first cylindrical correction lens group and the second cylindrical correction lens group are configured to move in coordination to introduce a variable cylindrical optical axis into the beam. Image display device.

20. At least one of the one or more self-adjustable cylindrical lenses is a liquid lens and / or liquid crystal lens. The image display device according to claim 19.

Images