Optometry Equipment

Abstract

To provide an optometer capable of improving inspection accuracy of the eye to be tested.SOLUTION: An optometer for presenting a test target to the eye to be tested and examining the eye to be tested includes: reply input means for inputting a reading result of a subject's test target; reply acquisition means acquiring reply information about the reading result on the basis of an input signal from the reply input means; anterior eye part image acquisition means acquiring an anterior eye part image of the eye to be tested; line of sight information acquisition means acquiring line of sight information about the line of sight of the eye to be tested on the basis of the anterior eye part image; and change control means changing a presentation state of the test target with respect to the eye to be tested on the basis of the reply information and the line of sight information.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to an optometry apparatus for measuring an eye to be examined. [Background technology]

[0002] There are known subjective optometry devices, visual acuity testing devices, and the like, which are capable of testing the subject's eye. For example, a subjective optometry device can measure the optical characteristics of the subject's eye by placing an optical element (e.g., a spherical lens, a cylindrical lens, etc.) in front of the subject's eye and presenting a test target to the subject through the optical element (Patent Document 1). Also, for example, a visual acuity testing device can measure the visual acuity of the subject's eye by having the subject look into a target window to confirm the test target (Patent Document 2). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 5-176893 [Patent Document 2] Japanese Patent Application Laid-Open No. 2000-287926 Summary of the Invention [Problem to be solved by the invention]

[0004] In tests using subjective eye examination devices or visual acuity testing devices, subjects can respond by intuition even if they cannot see the test target. For example, even if they are not gazing at the Landolt ring, they can respond by intuition about the direction of the slits in the Landolt ring. If the subject's responses when they properly see the test target and such intuitional responses are mixed, it becomes difficult to obtain accurate test results for the subject's eyes.

[0005] In view of the above-described conventional techniques, the present disclosure has as its technical object to provide an optometry apparatus capable of improving the accuracy of examining a subject's eye. [Means for solving the problem]

[0006] In order to solve the above problems, the present disclosure is characterized by having the following configuration.

[0007] An optometry apparatus according to the present disclosure is an optometry apparatus for presenting a test optotype to an eye to be examined and examining the eye to be examined, and includes: a response input means for inputting an interpretation result of the test optotype of the eye to be examined from the test subject; a response acquisition means for acquiring response information related to the interpretation result based on an input signal from the response input means; an anterior ocular segment image acquisition means for acquiring an anterior ocular segment image of the eye to be examined; a gaze information acquisition means for acquiring gaze information related to the gaze of the eye to be examined based on the anterior ocular segment image; and a change control means for changing a presentation state of the test optotype to the eye to be examined based on the response information and the gaze information. A detection area is provided for each test target to detect whether the position of the gaze coincides with the position of the test target, and the gaze information acquisition means acquires, as the gaze information, a determination result of whether the subject's eye is gazing at the test target based on a first timing when the input signal is obtained from the answer input means and a second timing when the position of the gaze is included in the detection area. It is characterized by: [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is an external view of a subjective optometry device. [Figure 2] FIG. 2 is a schematic diagram of a measurement unit. [Figure 3] FIG. 2 is a front view of the interior of the subjective optometry device. [Figure 4] FIG. 2 is a side view of the inside of the subjective optometry device. [Figure 5] FIG. 2 is a diagram showing the inside of the subjective optometry device as viewed from above. [Figure 6] FIG. [Figure 7] 10 is an example of an anterior eye image. [Figure 8] 1 is an example of a display. [Figure 9] 10 is a flowchart showing an example of the flow of subjective measurement. [Figure 10] 10 is a flowchart illustrating an example of change control in obtaining the highest visual acuity value. [Figure 11] 10 is a flowchart illustrating an example of change control in acquiring whether or not adjustment is performed. [Figure 12] FIG. 1 is an external view of a vision testing device. [Figure 13] FIG. 2 is a schematic diagram of the right-eye optical system of the vision testing device as seen from the right side. [Figure 14] 1 is a schematic diagram of a right-eye optical system and a left-eye optical system of a visual acuity testing device as viewed from above. [Figure 15] 10 is a flowchart illustrating an example of change control in the vision testing apparatus. DETAILED DESCRIPTION OF THE INVENTION

[0009] <Summary> An embodiment of an optometry device according to the present disclosure will be described. Items grouped in < > below can be used independently or in conjunction with each other.

[0010] The optometry apparatus of the present embodiment is an apparatus for presenting a test target to an eye to be examined and examining the eye. Note that the present technology can be applied to any apparatus that presents a test target to the eye to be examined.

[0011] <How to enter answers> The optometry apparatus of this embodiment may include a response input unit for inputting the subject's interpretation of the test optotype.

[0012] For example, the answer input means may be a means for the subject to input the results of his / her interpretation of the test optotype. In this case, the answer input means may be an operating means such as a lever switch or a push button switch (for example, the subject controller 8 and the subject controller 303). The answer input means may also be a voice input means such as a microphone. The answer input means may also be a detection means for detecting the movement of the subject's line of sight or gestures.

[0013] Furthermore, for example, the answer input means may be a means for an examiner to input the result of interpretation of the test optotype on behalf of the examinee. In this case, the answer input means may be at least one of an operation means, a voice input means, a detection means, etc.

[0014] The subject's interpretation result of the test optotype may be any result indicating whether or not the subject has interpreted the test optotype. For example, if the test optotype has a direction, the result may be a result of answering the direction of the test optotype. As an example, the result may be a result of answering the direction of the gap in a Landolt ring.

[0015] <Response information acquisition means> The optometry apparatus of this embodiment may include an answer acquisition means (for example, the control unit 10 and the control unit 340). The answer acquisition means acquires answer information regarding the interpretation result based on an input signal from the answer input means. The answer acquisition means may acquire the input signal from the answer input means as the answer information. For example, in this case, a signal indicating that a specific push button switch among multiple push button switches has been pressed may be acquired as the answer information. Of course, the answer acquisition means may also acquire a detection signal by the answer input means as the answer information. For example, in this case, a signal detecting the movement direction of the subject's line of sight may be acquired as the answer information.

[0016] Furthermore, the answer acquiring means may acquire, as the answer information, conversion information obtained by converting an input signal based on an input signal from the answer input means. For example, in this case, conversion information obtained by converting the pressing of a predetermined push button switch into the answer of the subject (for example, the direction of the gap in the Landolt ring target being "right") may be acquired as the answer information. Of course, the answer acquiring means may acquire, as the answer information, conversion information obtained by converting a detection signal based on a detection signal from the answer input means. For example, in this case, conversion information obtained by converting the movement direction of the subject's line of sight into the answer of the subject may be acquired as the answer information.

[0017] <Anterior segment image acquisition means> The ophthalmic examination apparatus of this embodiment may include an anterior eye image acquiring means (for example, the control unit 10). The anterior eye image acquiring means acquires an anterior eye image of the subject's eye. The anterior eye image may be an image including a bright spot image projected onto the subject's eye, or an image not including a bright spot image. The anterior eye image may be a single image obtained by photographing both the left and right subject's eyes, or two images obtained by photographing each of the left and right subject's eyes.

[0018] The ophthalmic examination apparatus may be provided with an anterior-eye-segment imaging means (e.g., the observation optical system 50 and the anterior-eye-segment observation unit 330) for imaging the anterior eye of the subject's eye. For example, the anterior-eye-segment imaging means may be provided integrally with a component (e.g., the optical system) constituting the ophthalmic examination apparatus. In this case, the anterior-eye-segment image acquisition means may acquire an anterior-eye-segment image as an imaging result of the anterior-eye-segment imaging means.

[0019] Of course, the anterior-eye-segment-image acquiring means may acquire an anterior-eye-segment image by receiving an image capturing result from another device having a function for capturing an image of the anterior eye of the subject's eye. For example, the anterior-eye-segment image may be acquired by a wearable device (e.g., a glasses-type wearable terminal, a head-mounted display, etc.).

[0020] <Method for acquiring line of sight information> The optometry apparatus of this embodiment may include a gaze information acquiring means (for example, the control unit 10 and the control unit 340). The gaze information acquiring means acquires gaze information relating to the gaze of the subject's eye based on an anterior eye image.

[0021] The gaze information acquiring means may acquire the eye position of the subject's eye as gaze information by analyzing the anterior eye image. For example, in this case, the gaze information acquiring means may detect the pupil center and the Purkinje image from the anterior eye image and acquire the eye position based on the positions of the pupil center and the Purkinje image. Note that the eye position may be acquired using the corneal curvature radius and the anterior chamber depth in addition to the positions of the pupil center and the Purkinje image.

[0022] The gaze information acquisition means may acquire the gaze position of the subject's eye as gaze information by image analysis of the anterior segment image. For example, the gaze position of the subject's eye may be acquired as a predetermined point or as an area centered on the predetermined point. In this case, for example, the gaze information acquisition means may detect at least one of the pupil center and the corneal apex from the anterior segment image and acquire the gaze position based on at least one of the pupil center and the corneal apex. As an example, the gaze position may be detected by inferring the gaze direction from the pupil center position or the corneal apex position. As another example, the gaze position may be detected by inferring the gaze direction from the deviation between the pupil center position and the corneal apex position. Note that the gaze position can also be acquired using electrooculography, corneal reflex analysis, scleral reflex analysis, etc.

[0023] The line-of-sight information acquiring means may acquire at least one of the eye position and the line-of-sight position of the subject's eye as line-of-sight information relating to the line of sight of the subject's eye.

[0024] The gaze information acquiring means may acquire, as gaze information, a determination result of whether the subject's eye is gazing at the test target. In this case, the gaze information acquiring means may determine whether the subject's eye is gazing at the test target by determining whether the eye position of the subject's eye exceeds a predetermined threshold associated with the position of the test target. In this case, the gaze information acquiring means may also determine whether the subject's eye is gazing at the test target by determining whether the gaze position of the subject's eye overlaps at least a portion of the test target. Of course, whether the subject's eye is gazing at the test target may be determined by taking into consideration both the determination result regarding the subject's eye position and the determination result regarding the gaze position of the subject's eye. This makes it easy to distinguish whether the subject's answer was made while looking at the test target or without looking at the test target.

[0025] For example, in this embodiment, a detection area may be provided for each test optotype to detect whether the position of the gaze of the subject's eye coincides with the position of the test optotype. For example, the detection area may be a detection area for detecting whether the position of the gaze of the subject's eye coincides with at least one of the positions (presentation position) in the left-right and up-down directions on the test optotype. Note that, for example, the detection area may be provided as a different area for each test optotype based on at least one of the distance from the subject's eye to the test optotype (i.e., test distance), the type of test optotype, the visual acuity value of the test optotype (in other words, the size of the test optotype), etc.

[0026] The detection area may also be provided as an area including at least a portion of the test optotype. For example, the detection area may be an area including the entire test optotype. In this case, the detection area may be a predetermined area based on the center of the test optotype. For example, the detection area may be an area including a portion of the test optotype. In this case, the detection area may be a predetermined area based on a predetermined portion of the test optotype (for example, the gap portion of the Landolt ring optotype).

[0027] When a detection area is provided for each test target, the gaze information acquisition means may acquire a determination result of whether or not the subject's eye is gazing at the test target based on whether or not the gaze position is included in the detection area. For example, the gaze information acquisition means may determine whether or not the subject's eye is gazing at the test target by taking into account the time during which the gaze position is included in the detection area. As an example, it may be determined that the subject is gazing at the test target when the gaze position is included in the detection area for a certain period of time or more. This clarifies the determination criteria for gazing at the test target, making it easier to obtain a determination result.

[0028] Furthermore, the gaze information acquiring means may acquire a determination result of whether or not the subject's eye is gazing at the test target, taking into consideration the timing of acquiring the subject's response information, thereby obtaining a highly accurate determination result that excludes cases where the gaze is accidentally focused on the test target.

[0029] For example, the gaze information acquisition means may acquire a determination result of whether the subject's eye is gazing at the test target based on whether the gaze position is included in the detection area when an input signal is obtained from the response input means. For example, it may be determined that the subject is gazing at the test target when a first timing at which the input signal is obtained from the response input means coincides with a second timing at which the gaze position is included in the detection area. Note that the coincidence of the first timing and the second timing also includes a state in which the first timing and the second timing are approximately coincident. Furthermore, for example, the gaze information acquisition means may determine that the subject is gazing at the test target when the second timing is included between the first timing and a predetermined timing before the first timing.

[0030] <Change control measures> The optometry apparatus of this embodiment may include a change control acquisition means (for example, the control unit 10 and the control unit 340). The change control means changes the presentation state of the test target to the subject's eye based on the answer information acquired by the answer acquisition means and the gaze information acquired by the gaze information acquisition means. This allows for obtaining accurate test results that take into account the position and direction of the subject's gaze as well as the correctness of the subject's answer.

[0031] The change control means may change the presentation state of the test optotypes to the subject's eye by controlling the optotype presenting means described later, so that the test optotypes are different from each other. For example, at least one of the orientation, visual acuity value, type, etc. of the test optotypes may be different before and after the change in the presentation state. This allows the test optotypes to be appropriately set in an appropriate state.

[0032] The change control means may change the presentation state of the test optotype to the subject's eye by controlling the optotype presenting means described below, so that the presentation areas in which the test optotype is presented are different from each other. In other words, the presentation position of the test optotype may be different before and after the change of the presentation state. The line of sight of the subject's eye moves significantly when the presentation position of the test optotype is changed randomly, which makes it easier to obtain accurate line of sight information. Note that if the optotype presenting means is a display, the presentation position of the test optotype can be easily changed.

[0033] The change control means may change the state of presentation of the test target to the eye to a state where the corrective powers for correcting the eye are different from each other by controlling the corrective means described later. For example, at least one of the spherical power, cylindrical power, astigmatic axis angle, etc. may be different before and after the change of the presentation state. This allows the corrective power to be appropriately set to an appropriate state.

[0034] Of course, the change control means may change the presentation state of the test optotypes to the test eyes to at least one of the following states: a state in which the test optotypes are different from each other, a state in which the presentation positions of the test optotypes are different from each other, and a state in which the correction powers of the test eyes are different from each other.

[0035] <Means for presenting visual targets> The optometry apparatus of this embodiment includes a target presenting means that emits a target light beam toward the subject's eye to present a test target to the subject's eye.

[0036] For example, the optotype presenting means may be a display (e.g., display 61). Also, for example, the optotype presenting means may be a light source and a DMD (Digital Micromirror Device). Also, for example, the optotype presenting means may be a light source and an optotype plate (e.g., an optotype illumination lamp 323 and an optotype plate 321). In this case, the light source may be a visible light source, and the optotype plate may be a disk having a plurality of test optotypes. For example, on the optical path along which the optotype light beam is guided to the subject's eye, the optotype plate is rotated by a motor or the like, so that the test optotypes are switched and positioned relative to the subject's eye.

[0037] The optotype presenting means may be provided so as to serve at least part of both the right eye optotype presenting means and the left eye optotype presenting means. The optotype presenting means may also be provided as a pair of right and left optotype presenting means, each of which has a right eye optotype presenting means and a left eye optotype presenting means. In this case, the right eye optotype presenting means and the left eye optotype presenting means may be formed of the same member. In this case, the right eye optotype presenting means and the left eye optotype presenting means may be formed of at least partly different members.

[0038] The optotype presenting means may have one presentation area capable of presenting the test optotype. Alternatively, the optotype presenting means may have multiple presentation areas capable of presenting the test optotype. For example, the multiple presentation areas may be areas that partially overlap each other.

[0039] For example, if the optotype presenting means is a display, the display surface of the display may be set as a single display area, thereby setting one presenting area for the test optotype. Alternatively, the display surface of the display may be divided into multiple display areas, thereby setting multiple presenting areas for the test optotype. Alternatively, if the optotype presenting means is a light source and an optotype plate, the shape of a mask member that masks part of the optotype plate may be changed, thereby setting one or multiple presenting areas for the test optotype. For example, the mask member may be a disk with an opening, or may also serve as part of a housing.

[0040] The target light beam from the target presenting means may be directly guided to the eye under examination. That is, the target light beam may be guided without passing through various optical members (e.g., lenses, mirrors, etc.). The target light beam from the target presenting means may be indirectly guided to the eye under examination. That is, the target light beam may be guided via various optical members. In this case, the target light beam may be guided via various optical members constituting the light projecting optical system (e.g., the light projecting optical system 60), the corrective optical system (e.g., the corrective optical system 80), etc.

[0041] <Correction means> The optometry apparatus of this embodiment includes a correcting unit that changes the optical characteristics of the target light beam in order to change the correction power for correcting the eye to be examined. For example, the optical characteristics of the target light beam may be at least one of spherical power, cylindrical power, and astigmatic axis angle.

[0042] The corrective optical system may have any configuration as long as it can change the optical characteristics of the target light beam.

[0043] For example, the corrective optical system may have an optical element, and the optical characteristics of the visual target light beam may be changed by controlling the optical element. For example, the optical element may be at least one of a spherical lens, a cylindrical lens, a cross cylinder lens, a rotary prism, a wavefront modulation element, a variable focus lens, etc. Of course, the optical element may be different from these.

[0044] As another example, the corrective optical system may change the optical characteristics of the target light beam by optically changing the presentation position (presentation distance) of the target relative to the eye to be examined. In this case, the target presenting means may be moved in the optical axis direction, or an optical element (e.g., a spherical lens) arranged in the optical path may be moved in the optical axis direction, or an optical element may be inserted or removed in the optical path. Of course, a combination of two or more of these configurations may also be used.

[0045] As another example, the correction optical system may have an optical element disposed between an optical member for guiding the target light beam from the light projecting optical system toward the subject's eye and the target presenting means, and the optical element may be controlled to change the optical characteristics of the target light beam. That is, the correction optical system may be a phantom lens refractometer (phantom correction optical system).

[0046] The correcting means may be provided so as to serve at least part of both the right eye correcting means and the left eye correcting means. Alternatively, the correcting means may be provided as a pair, each having a right eye correcting means and a left eye correcting means. In this case, the right eye correcting means and the left eye correcting means may be formed of the same member. Alternatively, in this case, the right eye correcting means and the left eye correcting means may be formed of at least some different members.

[0047] The optometry apparatus of this embodiment may be a subjective optometry apparatus that measures the optical characteristics of the subject's eye by placing an optical element in front of the subject's eye and presenting a test target to the subject via the optical element. The optometry apparatus may also be a visual acuity testing apparatus that measures the visual acuity of the subject's eye by having the subject look into a target window and check the test target. Of course, the optometry apparatus may be a different type of apparatus.

[0048] For example, when the eye examination apparatus is a visual acuity testing apparatus, the visual acuity testing apparatus may have a housing that houses an optotype presenting means, and an optotype window provided in the housing for viewing the test optotype presented inside the housing from inside the housing. In this case, the answer input means is used as a means for the subject to input the interpretation result obtained by peering into the optotype window and interpreting the test optotype, and the change control means may change the presentation state of the test optotype with respect to the subject's eye based on the correctness or incorrectness of the interpretation result as answer information and line of sight information. For example, by having such a configuration, the visual acuity testing apparatus may automatically test the visual acuity of the subject's eye.

[0049] <First Example> An example of the optometry apparatus according to this embodiment will be described.

[0050] In the following, a subjective optometry apparatus for subjectively measuring the optical characteristics of the subject's eye will be described as an example.

[0051] 1 is an external view of a subjective optometry device 100. For example, the subjective optometry device 100 includes a housing 2, a presentation window 3, a forehead rest 4, a chin rest 5, an examiner controller 6, a subject controller 8, an imaging unit 9, and the like.

[0052] The housing 2 houses inside it the measurement unit 7, deflection mirror 91, reflecting mirror 94, concave mirror 95, etc., which will be described later. The presentation window 3 is used to present a visual target to the subject's eye E. The forehead rest 4 is used to keep the distance between the subject's eye E and the device constant. The chin rest 5 is used to keep the distance between the subject's eye E and the device constant.

[0053] The examiner's controller 6 includes a switch unit 6b, a monitor 6a, etc. The switch unit 6b inputs signals for performing various settings (e.g., starting measurement, etc.). The monitor 6a displays various information (e.g., measurement results of the subject's eye E, etc.). The monitor 6a may also function as a touch panel that doubles as the switch unit 6b. Signals from the examiner's controller 6 are output to the control unit 10 via wired or wireless communication.

[0054] The subject controller 8 includes an answer lever 8a, an answer button 8b, and the like. The answer lever 8a is used when the subject inputs the result of interpreting the presented test optotype. For example, signals in four directions (up, down, left, and right) corresponding to the directions of the slits in the Landolt ring can be input by tilting the lever. The answer button 8b is used when the subject is unable to interpret the presented test optotype. The signal from the subject controller 8 is output to the control unit 10 via wired or wireless communication.

[0055] The imaging unit 9 is used to capture an image of the subject's face. The imaging unit 9 includes an imaging optical system (not shown). The imaging optical system may be configured by an imaging element and a lens.

[0056] <Measurement part> The measurement unit 7 includes a left eye measurement unit 7L and a right eye measurement unit 7R. In this embodiment, the left eye measurement unit 7L and the right eye measurement unit 7R are configured with the same member. Of course, each measurement unit may be configured with at least a part of a different member.

[0057] Fig. 2 is a schematic diagram of the measurement unit 7. In Fig. 2, the measurement unit 7 for the left eye 7L is taken as an example of the measurement unit 7. For example, the measurement unit 7L for the left eye includes a subjective measurement optical system 20, a first target projection optical system 30, a second target projection optical system 40, an observation optical system 50, etc. Note that, for example, the measurement unit 7L for the left eye may further include an objective measurement optical system.

[0058] <Subjective measurement optical system> The subjective measurement optical system 20 is used as part of a subjective measurement unit that subjectively measures the optical characteristics of the subject's eye E. In this embodiment, the ocular refractive power is measured as the optical characteristic of the subject's eye E. In addition to the ocular refractive power, other optical characteristics of the subject's eye E that may be measured include contrast sensitivity, binocular vision function (e.g., amount of heterophoria, stereoscopic vision function, etc.). For example, the subjective measurement optical system 20 is composed of a light projection optical system 60, a correction optical system 70, etc.

[0059] <Projection optical system> The light projection optical system 60 projects a visual target light beam toward the subject's eye E. For example, the light projection optical system 60 includes a display 61, a light projection lens 62, a light projection lens 63, a reflecting mirror 64, an objective lens 65, a dichroic mirror 66, a dichroic mirror 67, and the like.

[0060] A visual target (fixation target, test visual target, etc.) is displayed on the display 61. The visual target light beam emitted from the display 61 passes through optical members from the light projecting lens 62 to the dichroic mirror 67 in order, and is projected onto the eye E to be examined.

[0061] <Correction optical system> The correction optical system 70 is disposed in the optical path of the light projection optical system 60. The correction optical system 70 also changes the optical characteristics of the visual target light beam emitted from the display 61. For example, the correction optical system 70 includes an astigmatism correction optical system 80, a drive mechanism 75, and the like.

[0062] The astigmatism correcting optical system 80 is used to correct the cylindrical power and astigmatic axis angle of the subject's eye E. The astigmatism correcting optical system 80 is disposed between the projector lens 62 and the projector lens 63. The astigmatism correcting optical system 80 is composed of two positive cylindrical lenses 81a and 81b with the same focal length. The cylindrical lenses 81a and 81b are each rotated independently around the optical axis L1 by the driving of the rotation mechanisms 82a and 82b.

[0063] In this embodiment, the astigmatism correcting optical system 80 is described using cylindrical lenses 81a and 81b as an example, but is not limited to this. The astigmatism correcting optical system 80 may be configured to be able to correct cylindrical power, astigmatic axis angle, etc. As an example, a corrective lens may be inserted into or removed from the optical path of the projection optical system 60.

[0064] The drive mechanism 75 includes a motor and a slide mechanism. The drive mechanism 75 moves the display 61 in the direction of the optical axis L1. This allows the subjective measurement to optically change the presentation distance of the optotype relative to the subject's eye E, thereby correcting the spherical power of the subject's eye E. That is, a configuration that moves the display 61 in the direction of the optical axis L1 is used as a spherical correction optical system that corrects the spherical power of the subject's eye E, and the spherical power of the subject's eye E is corrected by changing the position of the display 61. Note that the spherical correction optical system may be configured to correct the spherical power by arranging multiple optical elements in the optical path. Alternatively, the spherical correction optical system may be configured to correct the spherical power by arranging a lens in the optical path and moving the lens in the optical axis direction.

[0065] The driving mechanism 75 may move a driving unit 76 that integrally synchronizes the display 61 in the subjective measuring optical system 20 with some of the optical members that make up the objective measuring optical system.

[0066] <First target projection optical system and second target projection optical system> The first target projection optical system 30 and the second target projection optical system 40 are disposed between a dichroic mirror 67 and a deflection mirror 91, which will be described later. The first target projection optical system 30 emits near-infrared light for projecting an alignment target at infinity onto the cornea of ​​the subject's eye E. The second target projection optical system 40 is disposed at a position different from the first target projection optical system 30, and emits near-infrared light for projecting an alignment target at finite distance onto the cornea of ​​the subject's eye. The near-infrared light (alignment light) emitted from the second target projection optical system 40 is also used as anterior segment imaging light for imaging the anterior segment of the subject's eye by the observation optical system 50.

[0067] <Observation optical system> The observation optical system (imaging optical system) 50 includes a dichroic mirror 67, an objective lens 51, an imaging lens 52, an imaging element 53, etc. The dichroic mirror 67 transmits the anterior segment observation light and the alignment light. The imaging element 53 has an imaging surface located at a position conjugate with the anterior segment of the subject's eye E. The output from the imaging element 53 is input to the control unit 10. As a result, an anterior segment image of the subject's eye E is captured by the imaging element 53 and displayed on the monitor 6a. The observation optical system 50 also serves as an optical system for detecting alignment target images formed on the cornea of ​​the subject's eye E by the first target projection optical system 30 and the second target projection optical system 40.

[0068] <Objective measurement optical system> The objective measurement optical system is used as part of an objective measurement unit that objectively measures the optical characteristics of the subject's eye E. The optical characteristics of the subject's eye E that may be measured include ocular refractive power, axial length, and corneal shape. For example, the objective measurement optical system may be composed of a projection optical system and a light-receiving optical system (for details, see, for example, Japanese Patent Application Laid-Open No. 2018-47049).

[0069] <Internal structure> 3 to 5 are schematic diagrams illustrating the internal configuration of the subjective optometry device 100. FIG. 3 is a diagram illustrating the internal configuration of the subjective optometry device 100 as viewed from the front. FIG. 4 is a diagram illustrating the internal configuration of the subjective optometry device 100 as viewed from the side. FIG. 5 is a diagram illustrating the internal configuration of the subjective optometry device 100 as viewed from the top. For convenience, only the optical axis of the measurement unit 7L for the left eye is shown in FIGS. 4 and 5.

[0070] The subjective ophthalmology device 100 includes a subjective measurement unit. For example, the subjective measurement unit includes a measurement unit 7, a deflection mirror 91, a drive mechanism 92, a drive unit 93, a reflection mirror 94, a concave mirror 95, and the like. However, the subjective measurement unit is not limited to this configuration. For example, the subjective measurement unit may not include the reflection mirror 94. In this case, the visual target light beam from the measurement unit 7 may be irradiated from an oblique direction with respect to the optical axis L2 of the concave mirror 95 after passing through the deflection mirror 91. Furthermore, for example, the subjective measurement unit may include a half mirror. In this case, the visual target light beam from the measurement unit 7 may be irradiated from an oblique direction with respect to the optical axis L of the concave mirror 95 via the half mirror, and the reflected light beam may be guided to the subject's eye E.

[0071] The subjective ophthalmology device 100 has a left eye drive unit 96L and a right eye drive unit 96R, and can move the left eye measurement unit 7L and the right eye measurement unit 7R in the X direction, respectively. For example, by moving the left eye measurement unit 7L and the right eye measurement unit 7R, the distance between the measurement unit 7 and the deflection mirror 91 changes, and the presentation position of the visual target light beam from the measurement unit 7 in the Z direction is changed. In this way, the visual target light beam corrected by the correction optical system 70 is guided to the subject's eye E, and the measurement unit 7 is adjusted in the Z direction so that an image of the visual target light beam corrected by the correction optical system 70 is formed on the fundus of the subject's eye E.

[0072] For example, the deflection mirror 91 has a pair of right-eye deflection mirrors 91R and left-eye deflection mirrors 91L provided on the left and right sides, respectively. For example, the deflection mirror 91 is disposed between the corrective optical system 70 and the subject's eye E. That is, the corrective optical system 70 in this embodiment has a pair of left-eye corrective optical systems and right-eye corrective optical systems provided on the left and right sides, with the left-eye deflection mirror 91L disposed between the left-eye corrective optical system and the left eye EL, and the right-eye deflection mirror 91R disposed between the right-eye corrective optical system and the right eye ER. For example, the deflection mirror 91 is preferably disposed at a pupil conjugate position.

[0073] For example, the left-eye deflection mirror 91L reflects the light beam projected from the left-eye measurement unit 7L and guides it to the left eye EL. Also, for example, the left-eye deflection mirror 91L reflects the fundus-reflected light beam from the left eye EL and guides it to the left-eye measurement unit 7L. For example, the right-eye deflection mirror 91R reflects the light beam projected from the right-eye measurement unit 7R and guides it to the right eye ER. Also, for example, the right-eye deflection mirror 91R reflects the fundus-reflected light beam from the right eye ER and guides it to the right-eye measurement unit 7R. Note that, in this embodiment, a configuration using the deflection mirror 91 as a deflecting member that reflects and guides the light beam projected from the measurement unit 7 to the subject's eye E has been described as an example, but the present invention is not limited thereto. The deflecting member may be, for example, a prism, a lens, or the like, as long as it can reflect and guide the light beam projected from the measurement unit 7 to the subject's eye E.

[0074] For example, the drive mechanism 92 includes a motor (drive unit) and the like. For example, the drive mechanism 92 includes a drive mechanism 92L for driving the left-eye deflection mirror 91L and a drive mechanism 92R for driving the right-eye deflection mirror 91R. For example, the deflection mirror 91 is rotated by the drive mechanism 92. For example, the drive mechanism 92 rotates the deflection mirror 91 about a rotation axis in the horizontal direction (X direction) and a rotation axis in the vertical direction (Y direction). In other words, the drive mechanism 92 rotates the deflection mirror 91 in the X and Y directions. Note that the rotation of the deflection mirror 91 may be in either the horizontal direction or the vertical direction.

[0075] For example, the drive unit 93 includes a motor or the like. For example, the drive unit 93 includes a drive unit 93L for driving the left-eye deflection mirror 91L and a drive unit 93R for driving the right-eye deflection mirror 91R. For example, the drive unit 93 moves the deflection mirror 91 in the X direction. For example, by moving the left-eye deflection mirror 91L and the right-eye deflection mirror 91R, the distance between the left-eye deflection mirror 91L and the right-eye deflection mirror 91R is changed, and the distance in the X direction between the left-eye optical path and the right-eye optical path can be changed in accordance with the interpupillary distance of the subject's eye E.

[0076] It should be noted that, for example, a plurality of deflection mirrors 91 may be provided in each of the optical path for the left eye and the optical path for the right eye. For example, a configuration in which two deflection mirrors are provided in each of the optical path for the left eye and the optical path for the right eye (for example, a configuration in which two deflection mirrors are provided in the optical path for the left eye) may be used. In this case, one deflection mirror may be rotated in the X direction, and the other deflection mirror may be rotated in the Y direction. For example, by rotating the deflection mirror 91, the apparent light beam for forming an image of the visual target light beam in front of the subject's eye can be deflected, and the position at which the image of the visual target light beam is formed can be optically corrected.

[0077] For example, the concave mirror 95 is shared by the left eye measurement unit 7L and the right eye measurement unit 7R. For example, the concave mirror 95 is shared by the left eye optical path including the left eye corrective optical system and the right eye optical path including the right eye corrective optical system. That is, the concave mirror 95 is disposed at a position where it passes through both the left eye optical path including the left eye corrective optical system and the right eye optical path including the right eye corrective optical system. Of course, the concave mirror 95 does not have to be shared by the left eye optical path and the right eye optical path. That is, a concave mirror may be provided in each of the left eye optical path including the left eye corrective optical system and the right eye optical path including the right eye corrective optical system. For example, the concave mirror 95 guides the visual target light beam that has passed through the corrective optical system 70 to the subject's eye E and forms an image of the visual target light beam that has passed through the corrective optical system 70 in front of the subject's eye E.

[0078] <Optical path of subjective measurement unit> The optical path of the subjective measurement unit will be described using the optical path for the left eye as an example. The optical path for the right eye has the same configuration as the optical path for the left eye. For example, in the subjective measurement unit for the left eye, the visual target light beam emitted from the display 61 in the subjective measurement optical system 20 enters the astigmatism correction optical system 80 via the projection lens 62. After passing through the astigmatism correction optical system 80, it is guided from the left eye measurement unit 7L toward the left eye deflection mirror 91L via the projection lens 63, the reflection mirror 64, the objective lens 65, the dichroic mirror 66, and the dichroic mirror 67. The visual target light beam reflected by the left eye deflection mirror 91L is reflected by the reflection mirror 94 toward the concave mirror 95. The visual target light beam emitted from the display 61 passes through each optical component in this manner and reaches the left eye EL through the presentation window 3.

[0079] As a result, an image of the visual target light beam corrected by the corrective optical system 70 is formed on the fundus of the left eye EL, based on the eyeglass wearing position of the left eye EL (for example, approximately 12 mm from the corneal vertex position). Therefore, adjustment of the spherical power by the spherical power corrective optical system (in this embodiment, by driving the drive mechanism 75) is performed in front of the eye, which is equivalent to placing the astigmatism correcting optical system 80 in front of the eye. The subject can collimate the image of the visual target light beam optically formed in front of the eye at a predetermined test distance via the concave mirror 95 in a natural state.

[0080] <Control unit> 6 is a diagram showing the control system of the subjective ophthalmology device 100. For example, the control unit 10 is electrically connected to various components such as the monitor 6a, the nonvolatile memory 15 (hereinafter referred to as memory 15), the display 61 provided in the measurement unit 7, the image pickup element 53, etc. Furthermore, for example, the control unit 10 is electrically connected to driving units (not shown) provided in the driving mechanism 75, the driving unit 93, the driving unit 96, etc.

[0081] For example, the control unit 10 includes a CPU (processor), RAM, ROM, etc. For example, the CPU controls each component in the subjective optometry device 100. For example, the RAM temporarily stores various types of information. For example, the ROM stores various programs, optotypes, initial values, etc. for controlling the operation of the subjective optometry device 100. Note that the control unit 10 may be configured with multiple control units (i.e., multiple processors).

[0082] For example, the memory 15 is a non-transitory storage medium that can retain stored contents even if the power supply is cut off. For example, the memory 15 may be a hard disk drive, a flash ROM, a USB memory, or the like.

[0083] <Control action> The control operation of the subjective optometry apparatus 100 will be described.

[0084] In subjective eye examinations using subjective optometry devices, the examinee is asked whether he or she can identify the test target, and the test target presented to the examinee's eye and the correction power used to correct the examinee's eye are changed depending on whether the examinee answers correctly or incorrectly. For example, the examinee is asked whether he or she can read the direction of the slits in a Landolt ring target, and the test target and correction power are changed depending on whether the reading is correct or incorrect. However, even if the examinee does not gaze at the Landolt ring target, if the examinee answers based on intuition, there is a certain probability that the answer will be correct. It is difficult for the examiner to determine whether an answer based on intuition is correct, and such correct answers may be mixed in, so conventional measurements may not produce accurate measurement results.

[0085] Therefore, in the subjective measurement in this embodiment, not only the answer of the examinee but also the gaze information of the examinee's eye is used to obtain a measurement result that takes into account a correct answer based on intuition. In particular, the measurement result that takes into account a case where the examinee's eye gives a correct answer even though he or she is not looking at the test target is obtained. This makes it possible to improve the measurement accuracy of the examinee's eye E.

[0086] This will be explained in detail below.

[0087] <Alignment of the test eye and the measurement unit> The examiner places the subject's face against the forehead rest 4 and chin rest 5, and causes the subject's eye E to fixate on a fixation target displayed on the display 61. The control unit 10 projects an alignment target onto the cornea of ​​the subject's eye E and photographs the anterior segment, thereby acquiring an anterior segment image including an alignment target image (a bright spot image, described below). The control unit 10 also detects the amount of deviation of the measurement unit 7 from the subject's eye E in the X, Y, and Z directions, and moves the measurement unit 7 based on this deviation amount. This automatically aligns the subject's eye E with the measurement unit 7.

[0088] <Subjective measurement> Next, the examiner performs subjective measurement on the subject's eye E. In this embodiment, response information regarding the interpretation result of the subject interpreting the test optotype and gaze information regarding the subject's gaze are acquired, and change control, which will be described later, is performed based on this information.

[0089] <Acquisition of response information> First, the acquisition of the subject's answer information will be described. For example, a Landolt ring is presented to the subject through the presentation window 3, and the subject is asked to indicate the direction of the slits. The subject determines the direction of the slits in the Landolt ring and either tilts the answer lever 8a or presses the answer button 8b. The control unit 10 acquires, as answer information, a detection result indicating whether the subject's answer is correct or incorrect, based on the direction of the slits in the Landolt ring presented to the subject's eye and a signal from the answer lever 8a or the answer button 8b.

[0090] For example, if a signal is input from the answer lever 8a, the answer of the subject is detected as correct or incorrect. For example, if the direction of the gap in the Landolt ring and the tilt direction of the answer lever 8a match, the answer is detected as correct, and if they do not match, the answer is detected as incorrect. Also, for example, if a signal is input from the answer button 8b, the answer of the subject is detected as no answer (I don't know).

[0091] <Acquiring gaze information> Next, acquisition of the subject's line of sight information will be described. Fig. 7 is an example of an anterior eye image 200 of the subject's eye E. The anterior eye image 200 includes a bright spot image R that appears due to the infrared light sources of the first target projection optical system 30 and the second target projection optical system 40. For example, the bright spot image R may be composed of a ring target image R1 that appears due to the infrared light source of the first target projection optical system 30 and a ring target image R2 that appears due to the infrared light source of the second target projection optical system 40.

[0092] The control unit 10 performs image processing on the anterior-segment image 200 to detect the pupil and the bright spot image R. For example, the pupil may be detected using luminance information on the anterior-segment image 200, and the pupil center P may be detected by calculating the center of the pupil. Alternatively, the corneal apex K may be detected using luminance information on the anterior-segment image 200 to detect the bright spot image R and calculate the center of either the ring target image R1 or the ring target image R2. The control unit 10 then detects the direction of the corneal apex K relative to the pupil center P and the amount of deviation Δd, and identifies the direction of the line of sight of the subject's eye E. For example, the amount of deviation Δd may be calculated by calculating the number of pixels between the pixel position of the pupil center P and the pixel position of the corneal apex K. Note that as the line of sight of the subject's eye E moves and the eye position of the subject's eye E (for example, the angle of rotation with respect to the optical axis L1 based on the center of rotation of the subject's eye) increases, the amount of deviation Δd increases. The direction of the line of sight of the subject's eye E is appropriately identified by calculating the deviation amount Δd. The control unit 10 can detect the line of sight position V (see FIG. 10 ) at which the subject's eye E gazes at the Landolt ring target, based on the direction of the line of sight of the subject's eye E and the distance from the subject's eye E to the display 61 (i.e., the examination distance).

[0093] FIG. 8 is an example of the display 61. A detection area D1 is provided on the Landolt ring T to detect whether the position of the gaze coincides with the Landolt ring T. For example, the detection area D1 may be provided for the entire Landolt ring T, or for a portion thereof (for example, a slit portion). Furthermore, for example, the detection area D1 may be provided as a fixed area (i.e., a fixed size and shape) where the examiner views the entire or a portion of the Landolt ring T. Note that, for example, the size and shape of the detection area D1 may be manually set by the examiner, or may be automatically set based on the results of experiments or simulations. In this embodiment, the detection area D1 is automatically set for the entire Landolt ring T.

[0094] The control unit 10 acquires, as gaze information, a determination result of whether or not the subject's eye is gazing at the Landolt ring target T, based on the direction of the gaze of the subject's eye. For example, the control unit 10 acquires a determination result of whether or not the subject's eye is gazing at the Landolt ring target T, based on a detection result of detecting whether or not the gaze position V of the subject's eye E, obtained by analyzing the anterior eye image 200 of the subject's eye E as described above, is included in the detection area D1 set for each Landolt ring target.

[0095] As an example, when the control unit 10 detects that the gaze position V of the subject's eye E is included in the detection area D1 for a predetermined time or more (for example, for one second or more), it may determine that the subject's eye E is gazing at the Landolt ring T. Furthermore, when the control unit 10 detects that the gaze position V of the subject's eye E is included in the detection area D1 for less than a predetermined time or when the control unit 10 detects that the gaze position V is not included in the detection area D1, it may determine that the subject's eye E is not gazing at the Landolt ring T.

[0096] Note that the timing at which a signal is input from the answer lever 8a or the answer button 8b may be taken into consideration when detecting whether the gaze position V is included in the detection area D1. For example, it may be considered whether the answer lever 8a or the answer button 8b is operated when the gaze position V is included in the detection area D1. Of course, it may also be considered, for example, whether the gaze position V was included in the detection area D1 during the time between the time when the answer lever 8a or the answer button 8b is operated and a predetermined time before that time (for example, one second before).

[0097] 9 is a flowchart showing an example of the flow of subjective measurement. For example, subjective measurement is performed in the order of adjusting the corrective power of the eye E to be examined (Step A), obtaining the best visual acuity value of the eye E to be examined (Step B), and obtaining whether or not the eye E to be examined is adjusted (Step C). Based on these results, the subjective value of the eye E to be examined is obtained (Step D). The subjective value of the eye to be examined may be the fully corrected value of the eye to be examined or may be a prescription value. The fully corrected value is the most positive corrective power value that provides the best visual acuity of the eye to be examined. The prescription value is a value used when prescribing glasses, and is a corrective power value that provides a predetermined visual acuity.

[0098] Steps A, B, C, and D will be described below in order, taking as an example a case where a perfectly corrected value is obtained as a subjective value of the eye to be examined.

[0099] <Adjusting correction power (Step A)> The examiner operates the monitor 6a to start subjective measurement. In response to a signal from the monitor 6a, the control unit 10 sets a correction power for correcting the eye E to a predetermined ocular refractive power based on a previously acquired objective value of the eye E. For example, the control unit 10 controls at least one of the correction optical system 70 and the projection optical system 60 based on the set correction power. As an example, the display 61 may be moved along the optical axis L1 to correct the spherical power of the eye E. As another example, the control unit 10 may rotate the cylindrical lenses 81a and 81b around the optical axis L1 to correct at least one of the cylindrical power and the astigmatic axis angle of the eye E. For example, the eye E is corrected to 0D.

[0100] The control unit 10 performs multiple tests on the subject's eye E to adjust the corrective power of the subject's eye E as appropriate. For example, first, a red-green test is performed on the subject's eye E, and a red-green target is displayed on the display 61. The subject answers whether they were able to clearly see the red target or the green target. The control unit 10 changes the spherical power based on the subject's answer. For example, next, a cross-cylinder test is performed on the subject's eye E, and a point cloud target is displayed on the display 61. The subject answers whether they were able to clearly see the two point cloud targets. The control unit 10 changes the astigmatic axis angle and the cylindrical power based on the subject's answer.

[0101] The control unit 10 may acquire line-of-sight information of the subject's eye E (whether the subject's eye E is gazing at each target) as described below. In this case, the line-of-sight information of the subject's eye E may be used together with the subject's response information (answers by the subject) to appropriately change the correction power of the subject's eye E. For example, this allows the correction power of the subject's eye E to be appropriately adjusted.

[0102] <Obtaining the highest visual acuity score (Step B)> 10 is a flowchart showing an example of change control in obtaining the best visual acuity value. The control unit 10 sets the presentation state of the test optotype to the eye E to the initial state. For example, the control unit 10 corrects the eye E with the correction power adjusted in step A (step B1), and displays a predetermined test optotype on the display 61 (step B2). As an example, a Landolt ring optotype with a slit facing rightward and a visual acuity value of 1.0 is displayed as the predetermined test optotype.

[0103] For example, the display 61 is provided with a presentation area J for presenting a test optotype (in other words, a display area J for displaying the test optotype). As an example, the presentation area J is provided based on the center of the display 61, and the test optotype is displayed based on the center of the presentation area J. This allows the subject's eye E to visually recognize a predetermined Landolt ring optotype.

[0104] When the presentation state of the test target to the eye to be examined is set to the initial state, a voice guide is generated from a speaker (not shown) or the like, asking the subject about the direction of the slit in the Landolt ring target. At this time, the control unit 10 changes the presentation state of the Landolt ring target to the eye to be examined based on the subject's answer information (whether the subject's answer is correct or incorrect) and the eye gaze information of the eye to be examined (whether the subject is gazing at the Landolt ring target T). For example, the presentation state is changed from the initial state (in other words, the first state) in which the corrective power adjusted in step A is given and a Landolt ring target with a visual acuity value of 1.0 and a slit facing rightward is presented to a second state in which at least one of the corrective power or the Landolt ring target is different. The state in which the corrective power is different may be a state in which at least one of the spherical power, cylindrical power, and astigmatic axis angle is different. Furthermore, the state in which the Landolt ring is different may be a state in which at least one of the direction of the slits in the Landolt ring and the visual acuity value is different.

[0105] In the initial state of the subject's eye E, the control unit 10 determines whether the subject's eye E is gazing at the target (step B3), and then, upon detecting whether the subject's answer is correct or incorrect (step B4), changes the initial state to the second state based on these results.

[0106] The control unit 10 first considers the determination result of whether the subject's eye E is gazing at the optotype, thereby eliminating the possibility that the subject answered the question about the direction of the slits without looking at the Landolt ring. For example, if the determination result indicates that the subject's eye E is not gazing at the optotype (step B3: NO), the visual acuity value of the Landolt ring may be lowered regardless of whether the subject's answer is correct or incorrect. As an example, the visual acuity value of the Landolt ring may be lowered by one level (i.e., the visual acuity value of the Landolt ring may be changed from 1.0 to 0.9). Furthermore, the direction of the slits of the Landolt ring may be changed regardless of whether the subject's answer is correct or incorrect. As an example, the direction of the slits of the Landolt ring may be changed from right to left. Of course, the visual acuity value of the Landolt ring may be lowered and the direction of the slits may be changed.

[0107] This sets a second state in which at least one of the visual acuity value of the Landolt ring or the direction of the slit is different from the initial state (step B5). Also, it is possible to prevent the measurement result from reflecting a correct answer despite not looking at the Landolt ring. After this, the process may return to step B3 in the second state, and control may be performed based on the flowchart.

[0108] For example, if the determination result indicates that the subject's eye E is gazing at the target (step B3: YES), the system determines whether the subject is viewing the Landolt ring target by taking into consideration the detection result that detects whether the subject's answer is correct or incorrect.

[0109] For example, if the detection result indicates that the subject's answer is incorrect or no answer (step B4: NO), the visual acuity value of the Landolt ring is changed to be lowered. At this time, the direction of the slits in the Landolt ring may be changed along with the visual acuity value of the Landolt ring. This sets a second state in which at least the visual acuity value of the Landolt ring is lower than the initial state (step B6).

[0110] For example, if the detection result indicates that the subject's answer is correct (step B4: YES), the visual acuity value of the Landolt ring is changed to be higher. As an example, the visual acuity value of the Landolt ring is changed to be one level higher (i.e., the visual acuity value of the Landolt ring is changed from 1.0 to 1.2). At this time, the direction of the slits in the Landolt ring may be changed along with the visual acuity value of the Landolt ring. This sets a second state in which the visual acuity value of at least the Landolt ring is higher than the initial state (step B10).

[0111] When the presentation state of the Landolt ring target to the subject's eye E is changed to each of the second states, the direction of the slit in the Landolt ring target is again inquired. As in steps B3 and B4, the control unit 10 performs change control based on the determination result of whether the subject's eye E is gazing at the target and the detection result of whether the subject's answer is correct or incorrect (steps B7 to B9, and steps B11 to B13).

[0112] When proceeding to step B6 with the second state set, if the subject's eye E gazes at the target and the answer is correct, the best visual acuity value in the state where the subject's eye E is corrected with the corrective power adjusted in step A is obtained (step B14). For example, the visual acuity value of the Landolt ring target presented to the subject's eye E in the second state (i.e., the Landolt ring target for which the answer was correct) is obtained as the best visual acuity value.

[0113] Furthermore, when proceeding to step B10 with the second state set, if the subject's eye E gazes at the optotype and the answer is incorrect or no answer, the best visual acuity value is obtained when the subject's eye E is corrected with the correction power adjusted in step A (step B14). For example, the best visual acuity value is not the visual acuity value of the Landolt ring optotype presented to the subject's eye E in the second state, but the visual acuity value of the Landolt ring optotype presented to the subject's eye E in the previous state (here, the initial state) and answered correctly.

[0114] When the process proceeds to step B6 with the second state set, if the subject's eye E gazes at the Landolt ring and the answer is incorrect, the process may return to step B6 and set the third state in which the visual acuity value of the Landolt ring is low. Also, when the process proceeds to step B10 with the second state set, if the subject's eye E gazes at the Landolt ring and the answer is correct, the process may return to step B10 and set the third state in which the visual acuity value of the Landolt ring is high.

[0115] Regardless of whether the second state is set to step B6 or step B10, if the line of sight does not match the Landolt target, the same change control as step B5 is performed, and a third state may be set in which at least one of the visual acuity value or the direction of the slits of the Landolt target is different (steps B9 and B13).

[0116] The control unit 10 changes the presentation state of the Landolt ring target with respect to the subject's eye E from the initial state to each of the second state, the third state, ..., the nth state in accordance with the flowchart. For example, the control unit 10 repeats such control and sequentially changes the presentation state to obtain the best visual acuity value when the subject's eye E is corrected with the correction power adjusted in step A.

[0117] <Obtaining Adjustment Status (Step C)> 11 is a flowchart showing an example of change control in acquiring the presence or absence of accommodation. The control unit 10 corrects the eye E to the corrective power adjusted in step A (step C1), and displays the Landolt ring on the display 61 (step C2). For example, the state in which the best visual acuity value of the eye E is acquired in step B is reproduced. Note that in step B, the corrective power is not changed from the initial state, so when moving from step B to step C, only the Landolt ring needs to be changed.

[0118] Next, the control unit 10 changes the corrective power of the subject's eye E so that it is lowered from the initial state (the state where the highest visual acuity value is obtained) (step C3). As an example, the spherical power is changed to a power one level lower (i.e., the spherical power is increased by +0.25D). Of course, the change is not limited to the spherical power, and the cylindrical power or astigmatic axis angle may also be changed.

[0119] Here, the subject is asked to indicate the direction of the gap in the Landolt ring target. The control unit 10 performs change control based on the determination result of whether the subject's eye E is gazing at the target or not and the detection result of whether the subject's answer is correct or incorrect (steps C4 to C6). Note that the details of these steps are the same as those of step B, so they will be omitted.

[0120] For example, if the subject's eye E gazes at the target and the answer is correct, it is determined that accommodation is working (step C7). In this case, the process may return to step B6, where the correction power is set to a state one step lower, and control may be performed based on the flowchart.

[0121] Also, for example, if the subject's eye E gazes at the target and the answer is incorrect or no answer is given, it is determined that accommodation is not working (step C8). The control unit 10 repeatedly changes the correction power of the subject's eye E according to the flowchart until it is determined that accommodation is not working in the subject's eye E.

[0122] <Obtaining perfect correction value> The control unit 10 adjusts the subject's eye E to a predetermined correction power in step A, acquires the best visual acuity value in a state in which the subject's eye E is corrected with the predetermined correction power in step B, and further decreases the correction power until the adjustment of the subject's eye E no longer works in step C, thereby acquiring the weakest correction power at which the subject's eye E has the best visual acuity as the fully corrected value of the subject's eye E. The control unit 10 also stores the fully corrected value of the subject's eye E in the memory 15.

[0123] <Correction of optical aberration components> In subjective measurement of the eye E, a third optical aberration component is generated based on a first optical aberration component generated by the subjective measurement unit and a second optical aberration component generated by the optical characteristics (ocular refractive power) of the eye E. For example, the first optical aberration component is generated because the reflection position or reflection area of ​​the visual target light beam on the concave mirror 95 (i.e., the beam diameter of the visual target light beam) changes depending on at least one of the alignment state of the eye E, the corrective power (i.e., spherical power, cylindrical power, astigmatic axis angle, etc.) set in the corrective optical system 70, the convergence angle of the visual target light beam, etc. For example, the second optical aberration component is generated because the shape of the visual target light beam changes depending on at least one of the spherical power, cylindrical power, and astigmatic axis angle of the eye E. For example, the third optical aberration component is a composite optical aberration component obtained by combining the first and second optical aberration components. For details about these optical aberration components, see, for example, Japanese Patent Application Laid-Open No. 2019-118551.

[0124] For this reason, the control unit 10 may calculate the third optical aberration component and correct it. For example, the third optical aberration component may be calculated using a table or an arithmetic formula created in advance based on the results of experiments or simulations, and the correction power may be changed based on the third optical aberration component to correct such aberration. Alternatively, for example, a simulation may be performed to track the target light beam when the correction power is changed in a calculation, to find a value of the correction power that eliminates the third optical aberration component, and then the correction power may be changed accordingly to correct such aberration (i.e., optimization may be performed). In this case, the simulation may be performed based on the positional relationship between the display 61 and the correction optical system 80, which is known from the design. The control unit 10 may more accurately acquire the subjective value of the subject's eye by reducing the influence of the third optical aberration component.

[0125] <Second Example> The above explanation uses a subjective eye examination device as an example, but even with a vision testing device, the presentation state of the Landolt ring target to the test eye E can be appropriately changed based on the test subject's response information and the gaze information of the test eye E, thereby making it possible to measure vision appropriately.

[0126] 12 is an external view of a vision testing device 300. The vision testing device 300 comprises a housing 301, a presentation window 302, a subject controller 303, a speaker 305, a printer 306, a lamp 307, a control box 308, and the like.

[0127] The housing 301 houses an optical system (described later) inside. The housing 301 also has a presentation window 302, a subject controller 303, an anterior eye illumination lamp 304, a speaker 305, and the like on the front side. The housing 301 also has a printer 306, a lamp 307, a control box 308, and the like on the side.

[0128] The presentation window 302 presents a test optotype from the inside to the outside of the housing 301. The presentation window 302 has a presentation window 302L for the left eye and a presentation window 302R for the right eye. For example, by looking into the presentation windows 302 (the presentation window 302L for the left eye and the presentation window 302R for the right eye), the subject can check the test optotype presented in the optotype window 314 (see FIGS. 13 and 14 ) and have their visual acuity measured.

[0129] The subject controller 303 includes an input button 303a, a response button 303b, a response lever 303c, etc. The input button 303a is used by the subject when starting the visual acuity test. The response button 303b is used when the subject is unable to interpret the presented test optotype. The response lever 303c is used by the subject when inputting the interpretation result of the presented test optotype.

[0130] The anterior-segment illumination lamp 304 emits near-infrared light for illuminating the subject's eye E, thereby illuminating the subject's eye E. The anterior-segment illumination lamp 304 includes an anterior-segment illumination lamp 304L for the left eye and an anterior-segment illumination lamp 304R for the right eye. Note that the anterior-segment illumination lamp 304 may be configured so that one lamp is used for both the left and right eyes. The anterior-segment illumination lamp 304 is disposed at a position where it can illuminate the subject's eye E. In this embodiment, the lamp is disposed around the presentation window 302. Of course, the lamp may also be disposed, for example, in a recess 309 where the subject's nose is located. Furthermore, for example, the lamp may be disposed at the end of a branched optical path between the image sensor 333 and the imaging lens 332 in the anterior-segment observation unit 330 described below, which is branched by a beam splitter or the like.

[0131] The speaker 305 outputs audio guidance and the like. The speaker 305 may be configured to have one on each side, or one shared by both the left and right. The printer 306 outputs the test results. The lamp 307 notifies the examiner of the test status, test results, and the like. The lamp 307 is placed in a position that is not visible when the examinee looks into the presentation window 302. The lamp 307 is equipped with multiple LEDs (light-emitting diodes) and is capable of emitting light in multiple colors (for example, two colors, green and orange). Of course, the lamp 307 may be configured to be made up of a single LED and emit light in a single color.

[0132] The control box 308 includes a monitor 308a. The monitor 308a functions as a touch panel that serves as both an operation unit for the examiner to input parameters and a display unit for checking the input parameters. A signal from the control box 308 is output to the control unit 340 via a cable 310. The control box 308 may be configured to be provided integrally with the housing 301.

[0133] <Optical system> Figure 13 is a schematic diagram of the right-eye optical system when the vision testing device 300 is viewed from the right side. The left-eye optical system when the vision testing device 300 is viewed from the left side has the same configuration as the right-eye optical system, so a description thereof will be omitted. Figure 14 is a schematic diagram of the right-eye optical system and the left-eye optical system of the vision testing device 300 when viewed from above. Note that Figure 14 also illustrates the configuration of the control system.

[0134] For example, the interior of the housing 301 includes eyepieces 311L and 311R, internal covers 312L and 312R, internal illumination lamps 313L and 313R, target windows 314L and 314R, a target presenting unit 320, an anterior eye observation unit 330, and the like.

[0135] The eyepieces 311L and 311R are disposed in the left eye presentation window 302L and the right eye presentation window 302R, respectively. As a result, when a test target is placed in the target window 314 provided on the back side of the presentation window 302 (the left eye presentation window 302L and the right eye presentation window 302R), the test target appears to be presented at an apparent distance (for example, 5 m) to the subject's eye E.

[0136] Internal illumination lamps 313L and 313R illuminate the visual field created by internal covers 312L and 312R. Internal covers 312L and 312R are cylindrical covers with a partition plate in the center. This ensures separate visual fields for the left eye EL and the right eye ER to view the test targets, and separates the left and right optical paths.

[0137] For example, in this embodiment, the inner covers 312L and 312R have the same shape. Furthermore, for example, the left and right inner wall surfaces of the inner covers 312L and 312R are formed symmetrically about an optical axis M1L, which is emitted from a target illumination lamp 323L and passes through the eyepiece 311L (described later), and an optical axis M1R, which is emitted from a target illumination lamp 323R and passes through the eyepiece 311R. Furthermore, for example, target windows 314L and 314R are provided on the back surfaces of the inner covers 312L and 312R, respectively. Therefore, when both test eyes (i.e., both the left test eye EL and the right test eye ER) look into the presentation window 302, the target windows 314L and 314R are fused and seen as one, and the left and right inner wall surfaces of the inner covers 312L and 312R are observed as a single visual field space. For example, this allows the subject to comfortably view a test target placed at an apparent distance.

[0138] The inner surfaces of the internal covers 312L and 312R are painted in a matte white finish, and are illuminated to a predetermined brightness by the internal illumination lamps 313L and 313R during normal visual acuity testing or during light adaptation for measuring visual recovery time. The internal illumination lamps 313L and 313R are positioned so that their illumination light does not directly strike the subject's eye.

[0139] The optotype presentation unit 320 is used to switch and place test optotypes in the optotype window 314. For example, the optotype presentation unit 320 includes an optotype plate 321, a motor 322, and optotype illumination lamps 323L and 323R. The optotype plate 321 is made of a light-transmitting glass plate. On this glass plate, directional test optotypes (e.g., Landolt rings with up / down and left / right directions) are formed using a light-blocking chrome coating. For example, such test optotypes may be formed in 12 levels of visual acuity values, from 0.1 to 1.0, 1.2, and 1.5. Furthermore, for example, such test optotypes may be formed corresponding to the positions of the optotype windows 314L and 314R so that the same paired test optotypes for the left eye EL and the right eye ER can be simultaneously presented.

[0140] The motor 322 rotates the optotype plate 321. As a result, the test optotypes for the left eye and the right eye are arranged in the optotype windows 314L and 314R, respectively. The optotype illumination lamps 323L and 323R illuminate the optotype plate 321 from behind. As a result, the test optotypes arranged in the optotype windows 314L and 314R are presented toward the presentation windows 302L and 302R.

[0141] In this embodiment, a display may be used as the optotype presenting unit 320, and the test optotypes may be switched and positioned by controlling the display on the display. In this case, for example, a display may be provided on the inner rear surface of the inner covers 312L and 312R.

[0142] The anterior eye observation unit 330 is used to observe the anterior eye of the subject's eye E. The anterior eye observation unit 330 includes a beam splitter 331, an imaging lens 332, an imaging element 333, and the like. The beam splitter 331 transmits a target light beam emitted by the target illumination lamps 323L and 323R to illuminate the test target. The beam splitter 331 also reflects a light beam reflected by the anterior eye illumination lamps 304L and 304R at the anterior eye. The imaging element 333 has an imaging surface positioned conjugate with the anterior eye of the subject's eye E. The output from the imaging element 333 is input to the control unit 340. As a result, an anterior eye image of the subject's eye E is captured and acquired by the imaging element 333.

[0143] For example, the anterior eye observation unit 330 may be provided as a pair, including an anterior eye observation unit for the left eye and an anterior eye observation unit for the right eye. Of course, the anterior eye observation unit 330 may be provided so that at least a portion of the anterior eye observation unit for the left eye and the anterior eye observation unit for the right eye are shared. As an example, only the image sensor 333 may be shared. As another example, the beam splitter 331, the image sensor 332, and the image sensor 333 may all be shared. In this case, part of the partition plate in the center of the inner cover 312 may be removed, and the beam splitter 331 may be placed therein.

[0144] <Control system> For example, the control unit 340 supervises and controls each unit of the vision testing apparatus 300. For example, the control unit 340 may be configured to include a CPU (processor), RAM, ROM, etc. For example, the CPU controls the driving of each component in the vision testing apparatus 300. For example, the RAM temporarily stores various types of information. For example, the ROM stores programs to be executed by the CPU. Note that the control unit 340 may be configured by multiple control units (i.e., multiple processors).

[0145] For example, the control unit 340 is electrically connected to an input button 303a, a response button 303b, a response lever 303c, a speaker 305, a printer 306, a lamp 307, anterior segment illumination lamps 304L and 304R, internal illumination lamps 313L and 313R, a motor 322, target illumination lamps 323L and 323R, a non-volatile memory 345 (memory 345), a control box 308, etc.

[0146] For example, the memory 345 is a non-transitory storage medium that can retain stored contents even if the power supply is cut off. For example, the memory 345 may be a hard disk drive, a flash ROM, a USB memory, or the like.

[0147] <Control action> The control operation of the visual acuity testing device 300 will now be described.

[0148] The examiner has the subject look into the presentation window 302. The control unit 340 detects that the subject has approached using a proximity sensor (not shown).

[0149] For example, at this time, a voice guide saying "Your visual acuity will be measured automatically. Please lightly push the lever" is emitted from the speaker 305. In response to a signal that the response lever 303c has been pushed, the control unit 340 turns on the anterior eye illumination lamp 304 (anterior eye illumination lamps 304L and 304R), the internal illumination lamp 17 (internal illumination lamps 313L and 313R), and the visual target illumination lamp 323 (visual target illumination lamps 323L and 323R).

[0150] For example, the speaker 305 then issues a voice guide saying, "Your visual acuity will be measured. Lightly tilt the lever in the direction of the broken ring. If you are unsure of the direction of the broken ring, press the button in front." When the subject responds using the response lever 303c or the response button 303b, a visual acuity test program for determining the visual acuity of the subject's eye is executed. Note that, for example, in such a visual acuity test program, the highest visual acuity value of the subject's eye E without eye contact is obtained.

[0151] 15 is a flowchart showing an example of change control in the visual acuity testing apparatus 300. For example, the control unit 340 sets the presentation state of the test target to the subject's eye E to the initial state. As an example, the control unit 340 rotates the target plate 321 and places a Landolt ring target with a visual acuity value of 0.5 as the initial test target in the target window 314 (target windows 314L and 314R) (step N1). Next, for example, the control unit 10 generates a voice guide such as "direction" from the speaker 305. The subject gazes at the Landolt ring target, determines the direction of the slit in the Landolt ring target, and either tilts the response lever 303c in that direction or presses the response button 303b.

[0152] Here, the control unit 340 determines whether the subject's eye E is gazing at the Landolt ring T, similar to the first embodiment, by using the anterior eye image photographed and acquired by the anterior eye observation unit 330 (step N2). Furthermore, the control unit 340 detects whether the subject's answer is correct or incorrect, similar to the first embodiment, based on the direction of the slit in the Landolt ring T presented to the subject's eye and the signal from the response lever 303c or the response button 303b (step N3). Furthermore, the control unit 340 changes the presentation state of the Landolt ring T to the subject's eye from the initial state to the second state, based on the determination result obtained in step N2 (i.e., line-of-sight information of the subject's eye E) and the detection result obtained in step N3 (i.e., information on the subject's answer).

[0153] 15 are basically the same as the flow from step B3 to step B14 in Fig. 10, and therefore detailed description thereof will be omitted. The control unit 10 changes the presentation state of the Landolt ring target to the subject's eye E from the initial state to each of the second state, the third state, ..., the nth state in accordance with the flowchart. For example, the control unit 10 repeats such control and appropriately changes at least one of the visual acuity value and the direction of the slits of the Landolt ring target presented in the target window 314 to a different state, thereby obtaining the best visual acuity value of the subject's eye E with the naked eye.

[0154] As described above, for example, the optometry device in this embodiment acquires answer information regarding the subject's interpretation of the test optotype and gaze information regarding the gaze of the subject's eye, and changes the presentation state of the test optotype to the subject's eye based on the answer information and gaze information. This makes it possible to obtain accurate test results that take into account the correctness of the subject's answer as well as the position and direction of the subject's gaze.

[0155] Furthermore, for example, the optometry apparatus in this embodiment acquires a determination result of whether the subject's eye is gazing at the test target as gaze information related to the gaze of the subject's eye, which makes it easy to distinguish whether the subject's answer was given while looking at the test target or without looking at the test target, thereby obtaining accurate test results.

[0156] Furthermore, for example, the optometry device in this embodiment is provided with a detection area for each test area to detect whether the position of the gaze of the subject's eye coincides with the position of the test target, and obtains a determination result of whether the subject's eye is gazing at the test target based on whether the position of the gaze is included in the detection area. This clarifies the determination criteria for gazing at the test target, making it easy to obtain a determination result.

[0157] Furthermore, for example, when the optometry device in this embodiment receives an input signal containing the result of interpretation of the test target of the subject, it acquires a determination result of whether or not the subject's eye is gazing at the test target based on whether or not the position of the gaze is included in the detection area. This allows for the case where the gaze coincides with the test target by chance to be taken into consideration, and makes it possible to obtain a highly accurate determination result.

[0158] Furthermore, for example, the optometry device in this embodiment includes a corrector that changes the optical characteristics of the target light beam in order to change the correction power for correcting the eye to be examined, and the state of presentation of the test target to the eye to be examined is changed to a state of presentation with different correction powers by controlling the corrector. As an example, at least one of the spherical power, cylindrical power, astigmatic axis angle, etc. is changed to a different state before and after the change. This allows the correction power to be appropriately adjusted based on the response information and line of sight information, thereby improving the accuracy of the examination.

[0159] <Example of transformation> In this embodiment, the presenting position of the Landolt ring is the center of the display 61 or the target window 314, but the presenting position is not limited to this. For example, the presenting position of the Landolt ring does not necessarily have to be a fixed position, and may be a random position.

[0160] When the Landolt rings are arranged at random positions in the subjective optometry device 100, the display 61 may be provided with a plurality of display areas. For example, the display surface of the display 61 may be divided into any number of vertical and horizontal sections to provide a plurality of display areas. As an example, in this embodiment, the display surface of the display 61 is divided into 3 x 3 sections (divided into three sections vertically and horizontally). Of course, the plurality of display areas may partially overlap, or a different layout may be used.

[0161] For example, in the change control according to the flowchart of Fig. 10, the control unit 10 randomly selects one of the multiple display areas. The control unit 10 then displays Landolt rings with different visual acuity values ​​or different slit directions in the center of the selected display area. In this way, for example, the Landolt rings can be arranged in random positions.

[0162] When the Landolt ring targets are arranged at random positions in the visual acuity testing device 300, the target window 314 in the target presentation unit 320 may be made large, and multiple Landolt ring targets may be arranged in the target window 314. Also, a mask plate for masking the Landolt ring targets may be rotatably arranged in front of the target plate 321. For example, the target plate 321 and the mask plate are controlled independently.

[0163] For example, in the change control according to the flowchart of Fig. 15, the control unit 340 rotates the target plate 321 to present a plurality of Landolt ring targets, including Landolt ring targets with different visual acuity values ​​or slit directions. The control unit 340 also rotates the mask plate to remove the target Landolt ring target and mask the remaining Landolt ring targets. For example, in this way, the Landolt ring targets can be arranged in random positions.

[0164] For example, the eye examination device in this embodiment includes a target presenting means for emitting a target light beam toward the eye to present a test target to the eye, and the target presenting means controls the test target presentation state to change the test target presentation state to a different test target. For example, in the case of a directional test target such as a Landolt ring target, at least one of the orientation of the test target, the visual acuity value of the test target, etc., is changed to a different state before and after the change. This allows the test target to be appropriately adjusted based on the response information and gaze information, thereby improving the accuracy of the examination.

[0165] In this embodiment, the case where the gaze information of the subject's eye E is acquired using the bright spot image R projected onto the subject's eye E has been described as an example, but the present invention is not limited thereto. For example, the gaze movement of the subject's eye E may be acquired in advance, and the gaze information of the subject's eye E may be acquired based on the acquired gaze movement. In this case, before starting the subjective measurement or visual acuity test, the control unit presents a fixation target to the subject's eye E and obtains a first detection result that detects the gaze position, pupil position, eye movement, etc. of the subject's eye E gazing at the fixation target. After starting the subjective measurement or visual acuity test, the control unit obtains a second detection result that detects the gaze position, pupil position, eye movement, etc. of the subject's eye E gazing at the Landolt ring target (test target). For example, the control unit can obtain a determination result of whether the subject's eye is gazing at the Landolt ring target by comparing the first detection result obtained in advance with the second detection result. Of course, when the Landolt ring is presented at random positions, the first detection result may be obtained at each position.

[0166] In this embodiment, a configuration in which one Landolt ring is presented during subjective measurement or visual acuity testing of the subject's eye E has been described as an example, but the present invention is not limited to this. For example, multiple Landolt rings may be presented. As an example, multiple Landolt rings with the same visual acuity value but different slit directions may be presented. As another example, multiple Landolt rings with different visual acuity values ​​but the same slit direction may be presented. As another example, multiple Landolt rings with different visual acuity values ​​and different slit directions may be presented. These multiple Landolt rings may be arranged in accordance with the tilt direction of the answer lever 8a (response lever 303c).

[0167] In this case, the control unit may ask which Landolt ring is facing right, or which Landolt ring is most easily visible, etc. The control unit may also change the presentation state of the Landolt ring to the eye E by using response information based on signals input from each lever and line-of-sight information of the eye E.

[0168] In this embodiment, the naked eye visual acuity of the subject's eye E may be measured using the subjective optometry device 100 of the first embodiment. In this case, for example, the display 61 may be placed at a position 0D corresponding to infinity, and only step B among steps A to D may be performed. In step B, step B1 may be omitted, and steps B2 and onward may be performed in order.

[0169] In this embodiment, the vision testing apparatus 300 of the second embodiment may be provided with a correction unit for correcting the refraction of the subject's eye E. For example, the correction unit may be provided in the optical path between the eyepiece 311 and the beam splitter 331. For example, the correction unit may have an optical element for correcting the subject's eye E, and a motor for inserting and removing the optical element into and from the optical path. The optical element may be a lens, a prism, or the like.

[0170] As a result, for example, the visual acuity testing apparatus 300 may be used to measure the unaided visual acuity of the subject's eye E and the corrected visual acuity when the subject's eye E is corrected. That is, the unaided visual acuity of the subject's eye E may be measured by removing an optical member in the optical path along which the visual target light beam from the visual target presenting unit 320 is guided to the subject's eye. Alternatively, the corrected visual acuity of the subject's eye E may be measured by inserting an optical member in the optical path along which the visual target light beam from the visual target presenting unit 320 is guided to the subject's eye. [Explanation of symbols]

[0171] 6 Examiner controller 10 Control Unit 20 Subjective measurement optical system 50 Observation optical system 60 Projection optical system 70 Corrective optical system 100 Subjective optometry device 300 Visual acuity measuring device 320 Visual target presentation unit 330 Anterior segment observation unit

Claims

1. An optometry apparatus for presenting a test target to an eye to be examined and examining the eye to be examined, comprising: A response input means for inputting the subject's interpretation result for the test optotype; an answer acquisition means for acquiring answer information related to the interpretation result based on an input signal from the answer input means; an anterior ocular segment image acquiring means for acquiring an anterior ocular segment image of the subject's eye; a line-of-sight information acquiring means for acquiring line-of-sight information regarding the line of sight of the subject's eye based on the anterior-segment image; a change control means for changing a presentation state of the test target with respect to the subject's eye based on the answer information and the line of sight information; Equipped with a detection area is provided for each of the test optotypes to detect a coincidence between a position of the line of sight and a position of the test optotype; The eye examination device is characterized in that the gaze information acquisition means acquires, as the gaze information, a determination result as to whether the test eye is gazing at the test target based on a first timing when the input signal is obtained from the answer input means and a second timing when the gaze position is included in the detection area.

2. In the optometric apparatus of claim 1, a target presenting means for presenting the test target to the subject's eye by emitting a target light beam toward the subject's eye, The eye examination apparatus, wherein the change control means controls the optotype presenting means to change the presented state of the test optotype so as to be different.

3. In the optometric apparatus of claim 2, a correction means for changing an optical characteristic of the visual target light beam in order to change a correction power for correcting the eye to be examined, The optometry apparatus, wherein the change control means controls the correction means to change the correction power of the subject's eye to a different value.

4. In the optometry device of claim 2 or 3, A housing that houses the optotype presenting means; a target window provided in the housing for confirming the test target presented inside the housing from outside the housing; having The answer input means is an answer input means for the subject to input an interpretation result of the subject peering into the optotype window and interpreting the test optotype, The change control means changes the presentation state based on the correctness of the interpretation result and the line of sight information, An optometry apparatus for automatically testing the visual acuity of the subject's eye.

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