Ophthalmic devices and ophthalmic programs

The optometry device and program address discrepancies in corneal vertex distances by converting objective refractive power to match subjective measurements, ensuring accurate and smooth refractive power application.

JP7841373B2Active Publication Date: 2026-04-07NIDEK CO LTD
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Patent Information

Authority / Receiving Office
JP · JP
Patent Type
Patents
Current Assignee / Owner
Filing Date
2022-07-04
Publication Date
2026-04-07

AI Technical Summary

Technical Problem

Existing ophthalmic examination systems face challenges in smoothly performing subjective measurements due to discrepancies between objectively and subjectively measured corneal vertex distances, leading to potential differences in applied refractive powers.

Method used

An optometry device and program that include target presentation, correction, and conversion means to adjust optical properties, allowing for the conversion of objective refractive power based on different measured distances to ensure accurate subjective measurements.

Benefits of technology

Enables smooth and accurate subjective refractive power measurements by correcting for discrepancies in corneal vertex distances, ensuring consistent refractive power application.

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Abstract

To provide an optometer and an optometry program which can smoothly perform subjective measurement.SOLUTION: An optometer comprises: target presentation means which emits a target light flux to a subject eye; and correction means which changes the optical characteristics of the target light flux, and subjectively measures the eye refractive power of the subject eye. The optometer also comprises: objective eye refractive power acquisition means which acquires the objective eye refractive power in objective measurement of the subject eye; first distance acquisition means which acquires a first distance to a reference position for lens attachment from a cornea apex of the subject eye in the objective measurement of the subject eye; second distance acquisition means which acquires a second distance to a reference position for lens attachment from the cornea apex of the subject eye in the subjective measurement of the subject eye; conversion means which converts the first objective eye refractive power based on the first distance into the second objective eye refractive power based on the second distance when the first distance is different from the second distance; and output means which outputs the second objective eye refractive power.SELECTED DRAWING: Figure 1
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Description

Technical Field

[0001] The present disclosure relates to an ophthalmic examination apparatus and an ophthalmic examination program for measuring the refractive power of an eye to be examined.

Background Art

[0002] There is known an eye refractive power measurement apparatus that projects a measurement light beam onto the fundus of an eye to be examined, receives the reflected light beam from the fundus with a light receiving element, and measures the heterophoric refractive power of the eye to be examined based on the output of the light receiving element (Patent Document 1). For example, in the eye refractive power measurement apparatus, the distance from the corneal apex position of the eye to be examined to the lens wearing reference position assuming that the eye to be examined wears glasses (distance between corneal apices) is set in advance to a predetermined distance.

[0003] In addition, there is known a subjective ophthalmic examination apparatus that uses an eye refractive power measurement unit disposed in front of the eye to be examined, arranges an optical element such as a spherical lens or a cylindrical (astigmatic) lens on the inspection window of the eye refractive power measurement unit, and presents a visual target to the eye to be examined through the optical element, thereby measuring the subjective refractive power of the eye to be examined (Patent Document 2).

[0004] At the start of subjective measurement using the subjective ophthalmic examination apparatus, the initial correction value (i.e., the initial value) of the eye refractive power measurement unit is set based on the heterophoric refractive power so that the eye to be examined is corrected with a predetermined refractive power. In addition, the distance between the corneal apices of the eye to be examined is adjusted to a constant distance. Subjective measurement is performed in such a state, and the subjective refractive power is obtained.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0006] Incidentally, if the corneal vertex distance measured objectively differs from the corneal vertex distance measured subjectively, even if an initial setting value is set based on the objective refractive power of the eye under examination and the prescribed refractive power is applied to the eye, the actual refractive power applied may differ from the prescribed refractive power. For example, in such cases, there were problems in performing subjective measurements smoothly, such as the time required to obtain subjective refractive power.

[0007] In light of the above-mentioned problems, this disclosure aims to provide an optometry device and optometry program that can smoothly perform subjective measurements of the eye being examined. [Means for solving the problem]

[0008] To solve the above problems, this disclosure is characterized by having the following configuration.

[0009] (1) An optometry device according to a first aspect of the present disclosure is an optometry device for subjectively measuring the refractive power of an eye, comprising: a target presentation means for emitting a target light beam toward an eye to be examined; a correction means for changing the optical properties of the target light beam; an optometry device for subjectively measuring the refractive power of an eye to be examined, comprising: an objective refractive power acquisition means for acquiring the objective refractive power of an eye to be examined in an objective measurement; a first distance acquisition means for acquiring a first distance from the corneal apex of an eye to be examined to a lens fitting reference position in the objective measurement; a second distance acquisition means for acquiring a second distance from the corneal apex of an eye to be examined to a lens fitting reference position in the subjective measurement; a conversion means for converting a first objective refractive power based on the first distance to a second objective refractive power based on the second distance when the first distance and the second distance are different; and an output means for outputting the second objective refractive power.

[0010] (2) An optometry program according to a second aspect of the present disclosure is an optometry program used in an optometry device that subjectively measures the refractive power of an eye, and includes a target presentation means for emitting a target light beam toward an eye to be examined, and a correction means for changing the optical properties of the target light beam, characterized in that it is executed by the processor of the optometry device to cause the optometry device to execute: an objective refractive power acquisition step for acquiring the objective refractive power of the eye to be examined in an objective measurement; a first distance acquisition step for acquiring a first distance from the corneal apex of the eye to be examined to a lens fitting reference position in the objective measurement of the eye to be examined; a second distance acquisition step for acquiring a second distance from the corneal apex of the eye to a lens fitting reference position in a subjective measurement of the eye to be examined; a conversion step for converting a first objective refractive power based on the first distance to a second objective refractive power based on the second distance if the first distance and the second distance are different; and an output step for outputting the second objective refractive power.

[0011] (3) An optometry device according to a third aspect of the present disclosure is an optometry device for measuring the refractive power of an eye to be examined, comprising: objective refractive power acquisition means for acquiring the objective refractive power of the eye to be examined in an objective measurement; first distance acquisition means for acquiring a first distance from the corneal apex of the eye to be examined to a lens fitting reference position in the objective measurement; second distance acquisition means for acquiring a second distance from the corneal apex of the eye to be examined to a lens fitting reference position in a subjective measurement; conversion means for converting a first objective refractive power based on the first distance to a second objective refractive power based on the second distance when the first distance and the second distance are different; and output means for outputting the second objective refractive power. [Brief explanation of the drawing]

[0012] [Figure 1] This is an external view of the subjective eye examination device according to this embodiment. [Figure 2] This is a schematic external view showing the front and rear views of the refractive power measurement unit according to this embodiment. [Figure 3] This is a diagram showing the corneal positioning unit. [Figure 4]It is a configuration diagram of an aiming scale plate and a reticle plate. [Figure 5] It is a schematic configuration diagram of a control system in a subjective ophthalmic apparatus. [Figure 6] It is a flowchart showing the flow of subjective measurement. [Figure 7] It is a configuration diagram of an objective eye refractive power measuring apparatus and a subjective ophthalmic apparatus. [Figure 8] It is a diagram showing the aiming scale plate and the reticle plate when confirming the corneal apex position. [Figure 9] It is a schematic diagram of a first distance in objective measurement and a second distance in subjective measurement. [Figure 10] It is a diagram in which an imaging element is arranged in a corneal position aiming unit. [Figure 11] It is an external view of a subjective ophthalmic apparatus.

Embodiments for Carrying Out the Invention

[0013] <Summary> Embodiments of the ophthalmic apparatus according to the present embodiment will be described. The items classified in the following <> can be used independently or in combination.

[0014] The ophthalmic apparatus of the present embodiment may be a subjective ophthalmic apparatus that subjectively measures the eye refractive power of an eye to be examined. For example, as the eye refractive power of the eye to be examined, at least any one of a spherical power, a cylindrical power, an astigmatic axis angle, etc. may be measured. Of course, the subjective ophthalmic apparatus may measure binocular vision functions (for example, at least any one of a prism amount, a stereoscopic vision function, etc.), contrast sensitivity, etc. in addition to the eye refractive power.

[0015] <Visual Target Presenting Means> The ophthalmic apparatus of the present embodiment may include visual target presenting means (for example, a visual target presenting unit 60). The visual target presenting means emits a visual target light beam toward the eye to be examined.

[0016] For example, the visual target presenting means may be a display (for example, display 61). Also, for example, the visual target presenting means may be a light source and a DMD (Digital Micromirror Device). Also, for example, the visual target presenting means may be a light source and a visual target board.

[0017] For example, the visual target light beam from the visual target presenting means may be directly guided toward the eye to be examined. Also, for example, the visual target light beam from the visual target presenting means may be guided through a light projecting optical system (for example, light projecting optical system 230) toward the eye to be examined. For example, the light projecting optical system may have at least one optical member for allowing the visual target light beam emitted from the visual target presenting means to pass therethrough. As an example, it may have at least any one of a lens, a mirror, etc.

[0018] <Correction means> The eye examination device of the present embodiment may include correction means. The correction means changes the optical characteristics of the visual target light beam emitted from the visual target presenting means. For example, the correction means may be disposed in the optical path of the light projecting optical system and change the optical characteristics of the visual target light beam.

[0019] The correction means may be any configuration that can change the optical characteristics of the visual target light beam.

[0020] For example, the correction means may have an optical element. For example, the optical element may be at least any one of a spherical lens, a cylindrical lens, a variable focus lens, a cross cylinder lens, a rotary prism, a wavefront modulation element, etc. Of course, the optical element may be different from these. In this case, by controlling the optical element, the optical characteristics of the visual target light beam are changed.

[0021] Furthermore, the corrective means may have a configuration for optically changing the presentation position (presentation distance) of the target to the eye under examination. For example, it may have a configuration for moving the target presentation means in the optical axis direction, or it may have a configuration for moving an optical element (e.g., a spherical lens) in the optical path in the optical axis direction. In this case, the optical properties of the target beam are changed by controlling a driving means for controlling at least one of the target presentation means and the optical element.

[0022] Furthermore, the corrective means may be, for example, an eye refractive power measuring unit (e.g., eye refractive power measuring unit 50) that switches and positions optical elements (e.g., optical elements 46) in front of the eye of the eye being examined via an examination window (e.g., examination window 53). For example, the eye refractive power measuring unit may have a lens disk (e.g., lens disk 45) in which multiple optical elements are arranged on the same circumference. In this case, the optical characteristics of the target light beam are changed by controlling a driving means (e.g., drive unit 56, drive unit 57, etc.) for controlling the lens disk.

[0023] <Method for obtaining objective refractive power> The optometry apparatus of this embodiment may include an objective refractive power acquisition means (for example, a control unit 70). The objective refractive power acquisition means acquires the objective refractive power of the eye being examined in an objective measurement. For example, the objective refractive power may be at least one of the following: spherical power, cylindrical power, astigmatism axis angle, etc.

[0024] For example, the objective refractive power acquisition means may acquire the objective refractive power input by the operator's operation means (e.g., controller 71). Alternatively, for example, the objective refractive power acquisition means may read an identifier for each subject and acquire the objective refractive power stored in the identifier. As an example, the identifier may be an ID, string, one-dimensional code, two-dimensional code, color code, etc. Alternatively, for example, the objective refractive power acquisition means may acquire the objective refractive power by receiving data measured using an eye refractive power measuring device that objectively measures the objective refractive power of the subject's eye by projecting a measurement light beam onto the fundus of the subject's eye and receiving the reflected light beam of the measurement light beam reflected by the fundus.

[0025] In the above-described refractive power measuring device, the first distance (described later) from the corneal apex position to the lens fitting reference position in the objective measurement of the eye under examination may be pre-set as a predetermined distance. For example, the first distance is pre-stored and set in the device as a standard distance (reference value) of 12 mm, which is generally considered the ideal corneal apex distance in Japan. Of course, the first distance may be a value other than 12 mm. The first distance may be set as a fixed reference value, or it may be set as a reference value that can be arbitrarily changed by the examiner. In this case, the objective refractive power acquisition means may receive at least one of the following data based on the first distance: spherical power, cylindrical power, astigmatism axis angle, etc.

[0026] <First distance acquisition means> The optometry device of this embodiment may include a first distance acquisition means (for example, a control unit 70). The first distance acquisition means acquires a first distance from the corneal apex position of the eye under examination to the lens fitting reference position in the objective measurement of the eye under examination. For example, the lens fitting reference position in the objective measurement may be a position where the spectacle lens is assumed to be positioned when the eye under examination is fitted with spectacle lenses. For example, the lens fitting reference position may be a position separated by a standard distance (reference value) from the corneal apex position of the eye under examination.

[0027] For example, the first distance acquisition means may acquire the first distance input by the operator's operation of the control means. Alternatively, for example, the first distance acquisition means may read an identifier for each subject and acquire the first distance stored in the identifier. Alternatively, for example, the first distance acquisition means may acquire the first distance by receiving data from the aforementioned refractive power measuring device. In this case, the first distance acquisition means and the objective refractive power acquisition means may be used interchangeably, and objective refractive power data may be received along with the first distance data.

[0028] <Second distance acquisition means> The optometry device of this embodiment may include a second distance acquisition means (for example, a control unit 70). The second distance acquisition means acquires a second distance from the corneal apex position of the eye under examination to the lens fitting reference position in the subjective measurement of the eye under examination. For example, the lens fitting reference position in the subjective measurement may be a position where the spectacle lens is assumed to be positioned when the eye under examination is fitted with spectacle lenses. For example, if the optometry device includes an eye refractive power measurement unit, the position where the optical element of the lens disk closest to the eye under examination is positioned may be used as the lens fitting reference position.

[0029] For example, the second distance acquisition means may acquire the second distance input by the operator's operation of the control means. Alternatively, for example, the second distance acquisition means may acquire the second distance based on the detection result detected by the detection means described later. Alternatively, for example, the second distance acquisition means may acquire the second distance which has been set as a fixed value in advance in the subjective ophthalmoscopic device.

[0030] <Conversion method> The optometry apparatus of this embodiment may include a conversion means (for example, a control unit 70). The conversion means converts the first objective eye refractive power based on the first distance to the second objective eye refractive power based on the second distance when the first objective distance and the second subjective distance are different. For example, the conversion means may convert the first objective eye refractive power to the second objective eye refractive power using a conversion table or calculation formula for converting the first objective eye refractive power to the second objective eye refractive power. Alternatively, for example, the conversion means may convert the first objective eye refractive power to the second objective eye refractive power by adding a conversion amount to the first objective eye refractive power using a conversion table or calculation formula for obtaining a conversion amount for converting the first objective eye refractive power to the second objective eye refractive power.

[0031] For example, the aforementioned conversion amount and second objective eye refractive power may be obtained such that the shift in the focusing position of the target light beam caused by the difference between the first objectively measured distance and the second subjectively measured distance is corrected by such a conversion table or calculation formula. For example, the conversion table or calculation formula may be obtained in advance from the results of experiments or simulations, etc., and stored in a memory means.

[0032] The conversion means may convert the first objective eye refractive power to the second objective eye refractive power when the difference between the first objective eye measurement distance and the second subjective eye measurement distance exceeds a predetermined threshold (predetermined distance). For example, the predetermined threshold for the difference between the first and second distances may be set as a fixed value in advance, or it may be set as an arbitrary value by the examiner.

[0033] The conversion means may convert the first objective eye refractive power to the second objective eye refractive power when the first objective eye refractive power measured by the objective method differs from the second objective eye refractive power measured by the objective method, and the first objective eye refractive power measured by the objective method exceeds a predetermined threshold (predetermined refractive power). For example, the predetermined threshold for the first objective eye refractive power may be set as a fixed value in advance, or it may be set as an arbitrary value by the examiner. Also, for example, the predetermined threshold for the first objective eye refractive power may be set for the direction in which the first objective eye refractive power is negative, or for the direction in which it is positive. Of course, the predetermined threshold for the first objective eye refractive power may be set for either the direction in which the first objective eye refractive power is negative or positive.

[0034] In this embodiment, the conversion means may convert the first objective refractive power to the second objective refractive power according to the values ​​of the first objective distance and the second subjective distance. Alternatively, in this embodiment, the conversion means may convert the first objective refractive power to the second objective refractive power based on a determination result of whether the first objective distance and the second subjective distance are different. In this case, the optometry device may include a determination means for determining whether the first objective distance and the second subjective distance are different. For example, an acceptable range may be provided for the difference between the first and second distances, and if the difference exceeds this acceptable range, it may be determined that the distances are different.

[0035] <Detection method> The optometry device of this embodiment may include a detection means. The detection means detects the second distance in the subjective measurement of the eye being examined. This makes it easy to determine whether the second distance in the subjective measurement matches the first distance in the objective measurement.

[0036] The detection means can be configured to measure the distance from the eye under examination to the lens fitting reference position. For example, the detection means may be an image sensor for imaging the eye under examination, and the distance may be detected by analyzing the image captured by the image sensor. Alternatively, for example, the detection means may project an indicator beam onto the cornea of ​​the eye under examination and measure the distance using an alignment indicator image based on the reflected beam of light reflected from the cornea. In other words, the detection means may be an alignment optical system. Alternatively, for example, the detection means may emit an optical signal toward the eye under examination and measure the distance by detecting the reflected signal of the optical signal reflected from the eye. In other words, the detection means may be an optical detector. Alternatively, for example, the detection means may emit an ultrasonic wave toward the eye under examination and measure the distance by detecting the reflected wave of the ultrasonic wave reflected from the eye. In other words, the detection means may be an ultrasonic detector. Of course, other optical systems and detectors may also be used.

[0037] <Output method> The optometry apparatus of this embodiment may include an output means (for example, a control unit 70). The output means outputs the second objectively observed refractive power, which is obtained by converting the first objectively observed refractive power by the conversion means.

[0038] For example, the output means may output the second objective refractive power to set the initial correction value of the correcting means. In this case, the optometry device may include a correction control means (e.g., a control unit 70) that sets the initial correction value of the correcting means based on the second objective refractive power output from the output means. For example, the initial correction value of the correcting means may be the value of the second objective refractive power. That is, it may be a correction value for correcting the eye under examination with the second objective refractive power. Alternatively, for example, the initial correction value of the correcting means may be a value different from the second objective refractive power and may be a correction value calculated based on the second objective refractive power. For example, it may be a correction value for correcting the eye under examination with a refractive power that uses the second objective refractive power as a guideline. As an example, it may be a correction value for correcting with a refractive power obtained by adding or subtracting a predetermined step (e.g., 0.25D) from the second objective refractive power.

[0039] The correction control means only needs to be able to change the refractive power of the eye being examined based on the initial correction value. For example, the target presentation means may be moved in the optical axis direction based on the initial correction value. Alternatively, for example, the optical elements in the optical path of the target light beam may be moved or inserted / removed relative to the optical axis based on the initial correction value. If the optometry device includes an eye refractive power measurement unit, the optical elements of each lens disk may be switched and arranged based on the initial correction value. By controlling at least one of the target presentation means and the optical elements in this way, the eye being examined is corrected to a predetermined refractive power at the start of the subjective measurement of the eye being examined, and the subjective measurement can be performed smoothly.

[0040] For example, the output means may output the second objective refractive power to prompt the examiner to set the initial correction value of the correction means. In this case, the optometry device may include a display control means that causes information based on the second objective refractive power output from the output means to be displayed on a display means. In this case, the optometry device may also include a print control means that causes information based on the second objective refractive power output from the output means to be printed on a printing means.

[0041] The information based on the second objective eye refractive power may be the value of the second objective eye refractive power, or it may be the initial correction value of the corrective means calculated based on the second objective eye refractive power. The initial correction value of the corrective means may be the value of the second objective eye refractive power, or it may be the correction value calculated based on the second objective eye refractive power. For example, the examiner may input information based on the second objective eye refractive power acquired by at least one of the display control means, print control means, etc., by operating the operating means. The corrective control means may set the initial correction value of the corrective means based on the operation signal from the operating means.

[0042] <Response Input Method> The optometry device of this embodiment may include a response input means. The response input means is a means for the subject to input their response to interpreting the test target. For example, the response input means may be an operating means such as a lever switch or a push-button switch (for example, a subject controller 220). The response input means may be provided integrally with the housing of the optometry device. Alternatively, the response input means may be provided separately from the housing of the optometry device.

[0043] The response input means may be configured to allow input in multiple predetermined directions. For example, it may allow input in four directions: up, down, left, and right. In other words, it may allow input of angles of 0° (360°), 90°, 180°, and 270°. Of course, it may allow input in more than four directions, or it may allow input in all directions from 0° to 359°.

[0044] <Control means> The optometry device of this embodiment may include control means. After the initial correction value of the correction means is set by the correction control means, the control means automatically proceeds with the subjective measurement based on the input signal from the response input means. More specifically, after changing the refractive power for correcting the eye under examination based on the initial correction value of the correction means, the control means automatically proceeds with the subjective measurement based on the input signal from the response input means. For example, a self-examination program may be run to allow the subject to perform a so-called self-examination, in which the subject performs the subjective measurement themselves. In self-examination, it is not easy to match the second distance of the subjective measurement with the first distance of the objective measurement, so there is a high possibility that the eye will be corrected with different refractive powers at the start of the subjective measurement. However, as in this embodiment, when the first distance and the second distance are different, the first objective refractive power based on the first distance is converted to the second objective refractive power based on the second distance and output, thereby correcting the eye under examination with a predetermined refractive power and enabling smooth subjective measurement.

[0045] The optometry device of this embodiment may be an objective optometry device that objectively measures the refractive power of the eye under examination. In an objective optometry device, it is also possible to convert the first objective refractive power based on a first distance to a second objective refractive power based on a second distance and output it. In this case, the optometry device may include: an objective refractive power acquisition means for acquiring the objective refractive power of the eye under examination in an objective measurement; a first distance acquisition means for acquiring the first distance from the corneal apex of the eye under examination to the lens fitting reference position in an objective measurement; a second distance acquisition means for acquiring the second distance from the corneal apex of the eye under examination to the lens fitting reference position in a subjective measurement; a conversion means for converting the first objective refractive power based on the first distance to a second objective refractive power based on the second distance when the first distance and the second distance are different; and an output means for outputting the second objective refractive power.

[0046] This disclosure is not limited to the apparatus described in this embodiment. For example, terminal control software (program) that performs the functions of the above embodiment can be supplied to a system or apparatus via a network or various storage media, and the control device (e.g., CPU) of the system or apparatus can read and execute the program.

[0047] <Examples> The following describes examples of the ophthalmoscopic device relating to this disclosure. The items classified in <> below may be used independently or in relation to each other.

[0048] <Device configuration> Figure 1 is a perspective view showing the entire subjective ophthalmoscopic device 1 from the front. For example, in this embodiment, the side where the eye to be examined E is located is described as the front of the entire subjective ophthalmoscopic device, and the side where the examiner's eye OE is located is described as the back of the entire subjective ophthalmoscopic device.

[0049] For example, the subjective optometry device 1 includes a support arm 2, an optometry table 3, a controller 71, an ocular refractive power measurement unit 50, a target presentation unit 60, etc. For example, the eye being examined E observes the test target from the front of the ocular refractive power measurement unit 50 through an examination window 53, which will be described later. For example, the examiner's eye OE observes the front of the eye being examined E from the rear of the ocular refractive power measurement unit 50 through an examination window 53, which will be described later. Also, for example, the examiner's eye OE observes the side of the eye being examined E from the rear of the ocular refractive power measurement unit 50 through a confirmation window 11, which will be described later.

[0050] <Eye Refractive Power Measurement Unit> The refractive power measurement unit 50 will be described below. Figure 2(a) is a schematic external view of the refractive power measurement unit 50 according to this embodiment, shown from the front (examined eye E side). Figure 2(b) is a schematic external view of the refractive power measurement unit 50 according to this embodiment, shown from the rear (examiner eye OE side). For example, the refractive power measurement unit 50 includes a forehead rest 51, a connecting part 52, a forehead rest adjustment knob 5, an examination window 53, a moving unit 54, a pair of left and right lens chamber units 55, etc.

[0051] For example, the forehead rest 51 fixes the position of the subject's face by making contact with the subject's forehead. As a result, the subject's eye E is kept at a constant distance from the examination window 53. For example, the connecting part 52 has one end connected to the forehead rest 51 and the other end connected to the moving unit 54. For example, the forehead rest adjustment knob 5 is used to adjust the position of the forehead rest 51.

[0052] For example, the moving unit 54 includes a drive unit 58, a drive unit 59, etc. For example, the drive unit 58 has a sliding mechanism to adjust the spacing of the lens chamber units 55. This allows the examiner to change the spacing of the examination windows 53 to match the interpupillary distance of the eye E being examined. Also, for example, the drive unit 59 has a convergence mechanism to adjust the convergence angle (collision angle) of the lens chamber units 55. For detailed information on the configuration of the moving unit, please refer to Japanese Patent Application Publication No. 2004-329345.

[0053] For example, the lens chamber unit 55 includes a light source 40, a lens disk 45, a drive unit 56, a drive unit 57, a corneal position aiming unit 10, a suppression unit 30, etc. For example, the light source 40 may be an LED (Light emitting diode). For example, the light source 40 includes a first light source 40a that illuminates one of the left or right eyes being examined, and a second light source 40b that illuminates the other of the left or right eyes being examined (see Figures 2(a) and 3). For example, in this embodiment, the first light source 40a is located in the left eye lens chamber unit 55L to illuminate the left eye EL, and the second light source 40b is located in the right eye lens chamber unit 55R to illuminate the right eye ER.

[0054] For example, the lens disc 45 has a large number of optical elements 46 (spherical lenses, cylindrical lenses, dispersion prisms, etc.) arranged on the same circumference. For example, the drive unit 56 (actuator, stepping motor, etc.) controls the rotation of the lens disc 45. This switches the optical elements 46 desired by the examiner into place in the inspection window 53. For example, the drive unit 57 (motor, solenoid, stepping motor, etc.) controls the rotation of the optical elements 46 placed in the inspection window 53. This positions the optical elements 46 in the left and right inspection windows 53 at the rotation angle desired by the examiner.

[0055] For example, the lens disk 45 consists of one lens disk or multiple lens disks. For example, if multiple lens disks (a group of lens disks) are provided, a drive unit corresponding to each lens disk is provided. For example, each lens disk in a group of lens disks is equipped with an aperture (or a 0D lens) and multiple optical elements. Typical types of lens disks include a spherical lens disk having multiple spherical lenses of different powers, a cylindrical lens disk having multiple cylindrical lenses of different powers, and an auxiliary lens disk. For example, an auxiliary lens disk may be equipped with at least one of a red filter / green filter, a prism, a cross-cylinder lens, a polarizer, a Maddox lens, or an auto-cross-cylinder lens. For detailed information on the configuration of the lens disks, please refer to Japanese Patent Publication No. 2007-68574 and Japanese Patent Publication No. 2011-72431.

[0056] <Corneal positioning unit> The corneal position aiming unit 10 will be described below. Figure 3 is a diagram showing the corneal position aiming unit 10. For example, the corneal position aiming unit 10 comprises a first corneal position aiming unit 10a and a second corneal position aiming unit 10b. For example, in this embodiment, a configuration is given in which the left eye lens chamber unit 55L has the first corneal position aiming unit 10a and the right eye lens chamber unit 55R has the second corneal position aiming unit 10b.

[0057] For example, the first corneal position aiming unit 10a is used to confirm the distance between the corneal vertex of one eye under examination (e.g., the left eye EL in this embodiment) illuminated by the first light source 40a and the lens mounting reference position (described later). For example, the first corneal position aiming unit 10a consists of a first confirmation window 11a, a first observation window 12a, and a first corneal position aiming optical system 20a. For example, the first confirmation window 11a is used to confirm the first corneal position aiming optical system 20a, which is located inside the eye refractive power measurement unit 50, from outside the eye refractive power measurement unit 50. For example, the first observation window 12a is used to guide the reflected light, which is irradiated from the first light source 40a and reflected by one eye under examination (e.g., the left eye EL), to the first corneal position aiming optical system 20a, which is located inside the eye refractive power measurement unit 50.

[0058] For example, the first corneal position aiming optical system 20a guides the reflected light, which is irradiated from the first light source 40a and reflected by one of the eyes under examination (e.g., the left eye EL), to the first confirmation window 11a. For example, the first corneal position aiming optical system 20a includes a reflective mirror 22, an aiming scale plate 23, a reticle plate 24, etc. For example, the reflective mirror 22 is positioned laterally (in the X direction) of the left eye EL. For example, the aiming scale plate 23 is provided between the reflective mirror 22 and the first confirmation window 11a. The aiming scale plate 23 may also be provided between the left eye EL and the reflective mirror 22. For example, the reticle plate 24 is positioned on the back side of the first confirmation window 11a (inside the left eye lens chamber unit 55L).

[0059] For example, Figure 4 is a diagram showing the configuration of the aiming scale plate 23 and the reticle plate 24. Figure 4(a) shows the aiming scale plate 23, and Figure 4(b) shows the reticle plate 24. For example, the aiming scale plate 23 has several scale lines N1 to N5, a center line N6, and a first index 27. For example, the scale lines N1 to N5 correspond to corneal vertex distances (see Figure 3) = 12 mm, 13.75 mm, 16 mm, 18 mm, and 20 mm, respectively. For example, scale line N2 (13.75 mm) is the reference position when the lens is fitted and is drawn to distinguish it from the other scale lines. For example, the center line N6 is used as a reference for aligning the reticle 28 on the reticle plate 24. Also, for example, the center line N6 is located in the left-right center of the aiming scale plate 23. For example, the reticle plate 24 has a reticle 28 and a second index 29, etc. For example, the reticle 28 is formed in a triangular shape. Furthermore, the reticle 28 is located in the left-right center of the reticle plate 24. For example, a numerical value 25 indicating the corneal vertex distance is displayed on the outer periphery of the reticle plate 24.

[0060] For example, the first indicator 27 on the aiming scale plate 23 and the second indicator 29 on the reticle plate 24 are indicators for guiding the examiner's eye OE to a predetermined distance from the reticle plate 24. For example, in this embodiment, when the examiner's eye OE is located 250 mm away from the reticle plate 24, the first indicator 27 and the second indicator 29 appear to overlap. For example, when the first indicator 27 is located inward relative to the second indicator 29, the examiner's eye OE is located closer than 250 mm from the reticle plate 24. Conversely, when the first indicator 27 is located outward relative to the second indicator 29, the examiner's eye OE is located further than 250 mm from the reticle plate 24. For detailed information on the configuration of the aiming scale plate and the reticle plate and their respective positional relationships, please refer to Japanese Patent Application Publication No. 2004-229769.

[0061] For example, the second corneal position aiming unit 10b is used to confirm the distance between the corneal vertex of the other eye under examination (e.g., the right eye ER in this embodiment), which is illuminated by the second light source 40b, and the lens fitting reference position. For example, the second corneal position aiming unit 10b consists of a second confirmation window 11b, a second observation window 12b, and a second corneal position aiming optical system 20b. For example, the second confirmation window 11b is used to confirm the second corneal position aiming optical system 20b, which is located inside the eye refractive power measurement unit, from outside the eye refractive power measurement unit 50. Also, for example, the second observation window 12b is used to guide the reflected light, which is irradiated from the second light source 40b and reflected by one of the eyes under examination (e.g., the left eye EL), to the second corneal position aiming optical system 20b, which is located inside the eye refractive power measurement unit 50.

[0062] For example, the second corneal position aiming optical system 20b guides the reflected light, which is irradiated from the second light source 40b and reflected by the other eye under examination (e.g., the right eye ER), to the second confirmation window 11b. Note that the configuration of the second corneal position aiming optical system 20b is the same as that of the first corneal position aiming optical system 20a, so its description is omitted in this embodiment. Of course, some parts of the configuration of these corneal position aiming optical systems may differ.

[0063] <Optotype presentation part> The target presentation unit 60 presents the test target to the eye E under examination. For example, the target presentation unit 60 may be a display, a light source and a DMD, a light source and a target board, etc. In this embodiment, a display 61 is used as the target presentation unit 60. For example, the display 61 may be an LCD (Liquid Crystal Display), an organic EL (Electro Luminescence), a plasma display, etc.

[0064] The display 61 is positioned at a predetermined distance from the eye refractive power measurement unit 50. For example, it is positioned at a distance (e.g., 5 m) required for performing a distance vision test on the eye E being examined. The display 61 is connected to the controller 71 wirelessly or via a wired connection and displays the test target in response to the operation signals input from the controller 71.

[0065] <Controller> For example, the controller 71 is used to input the subject's objective values ​​(e.g., spherical refractive power, cylindrical refractive power, astigmatism axis angle, etc.) and interpupillary distance, and to switch the arrangement of the optical elements 46 and the examination window 53 in the ocular refractive power measurement unit 50. Also, for example, the controller 71 is used to switch the test target presented to the eye E under examination. For example, the controller 71 is not fixed to the eye examination table 3, but can be carried around by the examiner at will.

[0066] For example, the controller 71 includes a display unit 72. For example, the display unit 72 displays information about the optical elements located in the eye refractive power measurement unit 50, the subject's refractive power information obtained from other devices, etc. For example, an operation signal input from the controller 71 is input to the control unit 70 via a cable. Alternatively, the operation signal from the controller 71 may be input to the control unit 70 via wireless communication such as infrared.

[0067] <Department Head> For example, Figure 5 is a schematic diagram of the control system in the subjective optometry device 1. For example, the control unit 70 is electrically connected to the controller 71, non-volatile memory 73, first light source 40a, second light source 40b, the drive units (drive units 56, 57, 58, 59) of the ocular refractive power measurement unit 50, the target presentation unit 60 (display 61), and the like.

[0068] For example, the control unit 70 includes a CPU (processor), RAM, ROM, etc. For example, the CPU is responsible for controlling each component of the subjective eye examination device 1. For example, RAM temporarily stores various types of information. For example, ROM stores various programs for controlling the operation of the subjective eye examination device 1. The control unit 70 may be composed of multiple control units (i.e., multiple processors).

[0069] For example, non-volatile memory 73 is a non-transient storage medium that can retain its contents even when the power supply is cut off. For example, a hard disk drive, flash ROM, USB memory, etc., can be used as non-volatile memory 73.

[0070] <Control operation> The operation of the subjective ophthalmography device having the above configuration will now be explained.

[0071] The procedure for subjective measurement using the subjective optometry device of this embodiment will be explained with reference to the flowchart in Figure 6. For example, first, with the left eye corrected to a predetermined correction power (initial correction value) based on the objective refractive power (objective value), subjective measurement of the left eye is performed, and the subjective refractive power (subjective value) of the left eye is obtained. After the measurement of the left eye is completed, the measurement of the right eye is performed in the same manner, and the subjective value of the right eye is obtained.

[0072] <Acquisition of objective values ​​using a subjective ophthalmoscopic device (S1)> In step S1, a first objective value is acquired to initiate subjective measurement of the eye under examination. The examiner retrieves the first objective value of the eye under examination, which was previously measured using the objective eye refractive power measuring device 100 (see Figure 7), and receives it into the subjective eye examination device. For example, the first objective value is stored in a memory (not shown) of the objective eye refractive power measuring device 100, associated with the subject's ID. For details on objective measurement using the objective eye refractive power measuring device, please refer to, for example, Japanese Patent Application Publication No. 2005-185523.

[0073] Figure 7 is a diagram showing the configuration of an objective eye refractive power measurement device and a subjective eye examination device. For example, in this embodiment, the objective eye refractive power measurement device 100 and the subjective eye examination device 1 are connected wirelessly. This enables the transmission and reception of data between the objective eye refractive power measurement device 100 and the subjective eye examination device 1. Of course, these devices may be connected by wire instead of wirelessly.

[0074] For example, the examiner operates the controller 71 of the subjective optometry device 1 and inputs the subject's ID. The control unit 70 of the subjective optometry device 1 outputs an operation signal to the objective refractive power measuring device 100 to send the first objective value associated with the subject's ID. When the control unit (not shown) of the objective refractive power measuring device 100 receives the subject's ID from the subjective optometry device 1, it retrieves the first objective value corresponding to the subject's ID from memory and transmits it to the subjective optometry device 1. The control unit 70 of the subjective optometry device 1 receives the first objective value transmitted from the objective refractive power measuring device 100. As a result, the control unit 70 can obtain the first objective value of the eye being examined.

[0075] <Acquisition of the first distance in a subjective optometry device (S2)> In step S2, the corneal vertex distance V1 (hereinafter referred to as the first distance V1) of the eye E under examination is obtained in an objective measurement. For example, the first distance V1 in the objective measurement is the distance from the corneal vertex of the eye E under examination to the position where the spectacle lens is assumed to be positioned when the eye under examination is fitted with spectacle lenses (lens fitting reference position). Details of the first distance V1 will be described later. In the objective measurement, the first distance V1 is set in advance as a predetermined distance, and the first objective value based on the first distance V1 is obtained. For example, in this embodiment, the first distance V1 is set to 12 mm, and assuming that the spectacle lens is placed 12 mm away from the eye E under examination, the refractive power that corrects the eye E to 0D (for example, spherical power, cylindrical power, and astigmatism axis angle, etc.) is obtained as the first objective value based on the first distance V1.

[0076] In this objective measurement of the eye E under examination, the first distance V1 is obtained based on the transmission and reception of data between the objective refractive power measuring device 100 and the subjective optometry device 1. For example, the first distance V1 is transmitted from the control unit of the objective refractive power measuring device 100 to the control unit 70 of the subjective optometry device 1, along with the first objective value in step S1. This allows the control unit 70 to obtain the first distance V1.

[0077] <Acquisition of the second distance in a subjective optometry device (S3)> In step S3, the corneal vertex distance V2 (hereinafter referred to as the second distance V2) is obtained using subjective measurement. For example, the second distance V2 in subjective measurement is the distance from the corneal vertex of the eye under examination E to the position where the spectacle lens will be positioned when the eye under examination is fitted with spectacle lenses (lens fitting reference position). Details of the second distance V2 will be described later. In subjective measurement, the second distance V2 is obtained by measuring the second distance V2 using the corneal position aiming unit 10.

[0078] First, the examiner instructs the subject to look into the examination window 53. The subject, in accordance with the examiner's instructions, places their face against the forehead rest 51 on the eye refractive power measurement unit 50 and looks into the examination window 53. At this point, the examiner operates the controller 71 to set a mode for observing the position of the subject's corneal apex, and the control unit 70 turns on the first light source 40a and the second light source 40b, respectively. As a result, the left eye EL and the right eye ER are illuminated with sufficient light.

[0079] Next, the examiner looks through the first confirmation window 11a of the left eye lens chamber unit 55L to confirm the position of the corneal apex of the left eye EL. Figure 8 shows the aiming scale plate 23 and reticle plate 24 when confirming the position of the corneal apex. The examiner searches for the position where the first index 27 on the aiming scale plate 23 and the second index 29 on the reticle plate 24 align vertically and horizontally, so that the first and second indexes overlap and appear as one. Furthermore, the examiner searches for the position where the tip of the reticle 28 and the center line N6 appear to align.

[0080] For example, as described above, the examiner adjusts the position of the forehead rest 51 on the refractive power measurement unit 50 by operating the forehead rest adjustment knob 5 (see Figure 2(b)) while checking the lateral position of the left eye EL using the first confirmation window 11a. This allows the position of the corneal apex of the left eye EL to be moved. For example, if the corneal apex of the left eye was located around the scale line N2 but was slightly off from the scale line N2, the position of the corneal apex can be made to match the scale line N2 by operating the forehead rest adjustment knob 5. After this, the examiner similarly adjusts the position of the corneal apex of the right eye ER using the second confirmation window 11b to match the position of the corneal apex with the scale line N2. Note that the position of the corneal apex of the left eye EL and the right eye ER can be adjusted from either side.

[0081] In this embodiment, since the position of the corneal apex of the eye under examination E coincides with the scale line N2, the second distance V2 of the eye under examination E is 13.75 mm. For example, the examiner reads a numerical value 25 indicating the corneal apex distance based on the scale line N2 and inputs the second distance V2 using the controller 71. As a result, the control unit 70 can acquire the second distance V2.

[0082] <Conversion of initial values ​​in subjective measurement (S4)> The control unit 70 starts subjective measurement of the eye E by adding a predetermined correction power (i.e., an initial value) to the eye E so that the eye E is corrected to a predetermined refractive power based on the first objective value. For example, a predetermined initial value is added to the eye E so that the target light beam from the display 61 is focused on the retina via the optical element 46 (in other words, so that the refractive power of the eye E becomes 0D). As an example, if the objective value of the eye E is a spherical power of -2.0D, a cylindrical power of -1.0D, and an astigmatism axis angle of 45 degrees, adding these powers and angles as initial values ​​will result in a refractive power of 0D.

[0083] In step S4, the initial values ​​used when starting such subjective measurements are converted as needed. In this embodiment, the control unit 70 sets the initial values ​​for subjective measurements based on the first objective value and first distance V1 in the objective measurement of the eye E under examination, and the second distance V2 in the subjective measurement. This will be explained in detail below.

[0084] Figure 9 is a schematic diagram of the first distance in objective measurement and the second distance in subjective measurement. Figure 9(a) shows the first distance. Figure 9(b) shows the second distance. For example, the first distance V1 in the objective eye refractive power measuring device 100 is, as described above, the distance from the position of the corneal apex 82 of the eye under examination E to the lens mounting reference position where the spectacle lens 80 is placed when the eye under examination wears spectacle lenses. More specifically, it is the distance from the position of the corneal apex 82 of the eye under examination to the position 81 of the posterior surface of the spectacle lens 80. For example, the second distance V2 in the subjective eye examination device 1 is, as described above, the distance from the position of the corneal apex 82 of the eye under examination E to the lens mounting reference position. In this embodiment, the eye refractive power measuring unit 50 is located in front of the eye under examination E, and the examination window 53 and multiple lens discs 45 are arranged in the order of moving away from the eye under examination E. For example, among the multiple lens discs 45, the optical element 46a of the lens disc 45 closest to the eye E being examined is positioned following the examination window 53. In the subjective optometry device 1, the second distance V2 can be considered as the distance from the position of the corneal apex 82 of the eye being examined to the position of the posterior surface of the optical element 46a.

[0085] In this case, if the first objective measurement distance V1 and the second subjective measurement distance V2 are different, the refractive power of the eye being examined may not be corrected to 0D even if an initial value based on the first objective value of the eye being examined is added.

[0086] For example, in Figure 9(a), the vertex-to-vertex distance of the corneal eye E is the first distance V1, and the target light beam directed towards the eye E is refracted by the spectacle lens 80, the cornea, and the lens, and focuses at the focal point f1 on the retina. In other words, the refractive power of the eye E is corrected to 0D. On the other hand, for example, as in Figure 9(b), if the vertex-to-vertex distance of the corneal eye E is the second distance V2, which is longer than the first distance V1, the target light beam directed towards the eye E is refracted by the optical element 46a located in front of the spectacle lens 80, as well as the cornea and the lens, and focuses at the focal point f2 behind the retina. Note that if the spectacle lens 80 and the optical element 46a are negative lenses, the longer the second distance V2 is relative to the first distance V1, the further behind the retina the target light beam will be located. Although not shown in the diagram, the shorter the second distance V2 is compared to the first distance V1, the closer the target light beam will be positioned in front of the retina.

[0087] Therefore, if the first objective value of the eye under test is set as the initial value for subjective measurement, and there is a discrepancy V3 between the first distance V1 and the second distance V2, a discrepancy 84 will occur between the focusing position f1 and the focusing position f2. As a result, the actual refractive power of the eye when the eye under test looks at the display 61 via the refractive power measurement unit 50 will be corrected to a value different from 0D. For example, even if the first objective value of the eye under test is a spherical power of -2.0 and a spherical lens of -2.0D is placed as the optical element 46, the eye under test will be in the same state as if it were looking at the test target through a spherical lens weaker than -2.0D (for example, -1.75D).

[0088] Therefore, in this embodiment, if the first objective measurement distance V1 and the second subjective measurement distance V2 are the same, the first objective value of the objective measurement is set as the initial value of the subjective measurement. If the first objective measurement distance V1 and the second subjective measurement distance V2 are different, the first objective value of the objective measurement is converted (corrected) based on the first distance V1 and the second distance V2 to obtain a second objective value, and this second objective value is set as the initial value of the subjective measurement.

[0089] In this embodiment, the first objective value of the eye under examination is converted based on the difference between the first distance V1 and the second distance V2. For example, a correction amount is determined to convert the first objective value based on the first distance V1 to the second objective value based on the second distance V2 by using a lookup table that associates the first objective value of the eye under examination with the difference between the first distance V1 and the second distance V2. As an example, the lookup table is configured to determine the correction amount to be added to the first objective value by referring to the first objective value of the eye under examination and the difference between the first distance V1 and the second distance V2.

[0090] For example, the lookup table may be pre-set based on experimental or simulation results, etc. As an example, the refractive power corresponding to the shift 84 in the focusing position of the target light beam, which changes when the first distance V1 and the second distance V2 are different, may be determined by experiment or simulation, and this refractive power may be pre-set so that it can be obtained as a correction amount. Note that a lookup table may be provided for each spherical power, cylindrical power, and astigmatism axis angle, and is stored in the non-volatile memory 73.

[0091] For example, the control unit 70 retrieves a lookup table from the non-volatile memory 73 and refers to the first objective value of the eye under examination and the amount of deviation between the first distance V1 and the second distance V2. In this embodiment, since the first distance V1 is 12 mm and the second distance V2 is 13.75 mm, the amount of deviation is 1.75 mm. As a result, the control unit 70 can obtain a correction amount corresponding to the deviation of 1.75 mm for converting the first objective value to the second objective value, and can also obtain the second objective value by adding the correction amount to the first objective value.

[0092] <Measurement of subjective perception (S5)> In step S5, the second objective value obtained in step S4 is set as the initial value, and subjective measurement of the eye under examination is started. For example, the control unit 70 controls the rotation angle of the lens disk 45 and the rotation angle of the optical element 46 to correct the eye under examination E with the second objective value. For example, the rotation angle of the lens disk 45 is changed to position the optical element 46 with the spherical power and cylindrical power of the second objective value in the eye examination window 53. Alternatively, the rotation angle of the optical element 46 with the cylindrical power of the second objective value is changed to position it in the eye examination window 132 with the astigmatic axis angle of the second objective value. This allows the second objective value to be added to the eye under examination E. As a result, even if the first objective measurement distance V1 and the second subjective measurement distance V2 are different, the difference in focal positions (f1 and f2) 84 (see Figure 9(b)) is corrected, and the target light beam incident on the eye under examination is focused onto the retina via the optical element 46 (the refractive power of the eye under examination is corrected to 0D).

[0093] The examiner conducts a subjective measurement of the subject eye E at the distance, changing the test target presented to the subject eye E and the corrective power applied to the subject eye. For example, the examiner operates the controller 71 to select a desired test target. The control unit 70 retrieves the corresponding test target data from the non-volatile memory 73 in response to the input signal from the controller 71 and displays it on the display 61. The test target displayed on the display 61 is presented to the subject eye E via the test window 53 and optical element 46 of the refractive power measurement unit 50. For example, the examiner switches the test targets and asks the subject how well they can see them. For example, if the subject's answer is correct, the examiner switches to a target with a higher visual acuity value. For example, if the subject's answer is incorrect, the examiner switches to a target with a lower visual acuity value. Furthermore, for example, the examiner conducts the examination while changing the corrective power of the eye E being examined, along with switching the test target.

[0094] <Acquisition of self-awareness (S6)> In step S6, subjective values ​​of the eye under examination E are acquired. For example, the control unit 70 stores the measurement results such as spherical power, cylindrical power, and astigmatism axis angle as subjective values ​​of the eye under examination E in the non-volatile memory 73. The subjective values ​​of the eye under examination E are also displayed on the display unit 72 of the controller 71.

[0095] As explained above, for example, the eye examination device of this embodiment includes: an objective refractive power acquisition means for acquiring the objective refractive power of the eye under examination in an objective measurement; a first distance acquisition means for acquiring the first distance from the corneal apex of the eye under examination to the lens fitting reference position in an objective measurement; a second distance acquisition means for acquiring the second distance from the corneal apex of the eye under examination to the lens fitting reference position in a subjective measurement; a conversion means for converting the first objective refractive power based on the first distance to the second objective refractive power based on the second distance when the first distance and the second distance are different; and an output means for outputting the second objective refractive power. For example, when the first distance and the second distance are different, the focusing position of the target light beam incident on the eye under examination may shift, and the eye may actually be corrected with a different refractive power at the start of the subjective measurement of the eye under examination. However, by outputting a second objective refractive power that takes into account such a shift in the light-gathering position, the eye under examination can be correctly corrected to a predetermined refractive power (for example, 0D), and subjective measurements can be performed smoothly.

[0096] Furthermore, for example, the optometry device of this embodiment sets the initial correction value of the correction means based on the second objective refractive power obtained by converting the first objective refractive power. This allows the eye to be easily corrected to a predetermined refractive power so that the shift in the focusing position of the target light beam incident on the eye is suppressed at the start of subjective measurement of the eye, and subjective measurement can be performed smoothly.

[0097] <Example of transformation> In this embodiment, when acquiring the second distance V2 in the subjective measurement of the eye E under examination, the position of the corneal apex 82 of the eye E under examination is finely adjusted to match the scale line N2 closest to the corneal apex 82, and the numerical value 25 is read and input. However, the embodiment is not limited to this. For example, a scale line for positioning the corneal apex 82 of the eye E under examination may be predetermined, and the numerical value 25 corresponding to this scale line may be pre-set as the second distance V2. In other words, the second distance V2 may be pre-set as a fixed distance. This eliminates the need for the examiner to input the second distance V2 into the device. In this case, the examiner can adjust the second distance V2 by operating the forehead adjustment knob 5 (see Figure 2(b)) so that the position of the corneal apex 82 of the eye E under examination coincides with a predetermined scale line.

[0098] Furthermore, in this embodiment, we have explained, as an example, how to determine a correction amount for converting the first objective value based on the first distance V1 to the second objective value based on the second distance V2 by using a lookup table that associates the first objective value of the eye under examination with the amount of deviation between the first distance V1 and the second distance V2. However, we are not limited to this. For example, a predetermined calculation formula may be used that can calculate a correction amount based on the first objective value of the eye under examination and the amount of deviation between the first distance V1 and the second distance V2.

[0099] Furthermore, in this embodiment, the second objective value obtained by adding a correction amount to the first objective value of the eye under examination E was described as the initial value for subjective measurement, but the embodiment is not limited to this. For example, it may be possible to select whether to set the first objective value or the second objective value of the eye under examination E as the initial value for subjective measurement. In this case, the control unit 70 may display the first objective value obtained by objective measurement and the second objective value obtained by adding a correction amount to the first objective value on the display unit 72 of the controller 71. In addition, the control unit 70 may set a value corresponding to the operation signal based on the examiner's selection as the initial value and switch the arrangement of the optical elements.

[0100] In this embodiment, when the first objective measurement distance V1 and the second subjective measurement distance V2 are different, the initial value for starting the subjective measurement is set based on the second objective value obtained by converting the first objective value of the objective measurement, but the embodiment is not limited to this. For example, the control unit 70 may convert the first objective value to the second objective value and set the initial value based on the second objective value when the first distance V1 and the second subjective measurement distance V2 are different and the first objective value exceeds a predetermined threshold. For example, the first objective value may be converted to the second objective value when the spherical frequency S in the first objective value exceeds a predetermined threshold. Also, for example, the first objective value may be converted to the second objective value when the cylindrical frequency C in the first objective value exceeds a predetermined threshold. Also, for example, the first objective value may be converted to the second objective value when the astigmatism axis angle A in the first objective value exceeds a predetermined threshold. In this embodiment, the first objective value may be converted to the second objective value if the spherical frequency S exceeds a predetermined threshold.

[0101] For example, in this embodiment, the optometry device converts the first objective refractive power based on the first distance to the second objective refractive power based on the second distance when the first objective refractive power in objective measurement differs from the second objective refractive power in subjective measurement, and when the first objective refractive power exceeds a predetermined threshold. For example, the larger the absolute value of the first objective refractive power (i.e., the higher the degree of the first objective refractive power), the greater the actual change in refractive power caused by the difference between the first distance in objective measurement and the second distance in subjective measurement. Therefore, in situations where the effect of the difference between the first and second distances becomes greater, the eye under examination can be correctly corrected to the predetermined refractive power by converting the first objective refractive power to the second objective refractive power and outputting it.

[0102] In this embodiment, the case in which the examiner reads the second distance V2 using the aiming scale plate 23 and the reticle plate 24 has been described as an example, but the embodiment is not limited to this. For example, the refractive power measurement unit 50 may be provided with a detection unit for detecting the second distance V2 so that the second distance V2 can be acquired automatically. In this embodiment, the case in which an image sensor is used as such a detection unit is given as an example.

[0103] Figure 10 shows the arrangement of image sensors in the corneal position aiming unit. For example, the image sensor 13 for detecting the second distance V2 is positioned behind the first confirmation window 11a and the second confirmation window 11b, respectively. As a result, reflected light emitted from the first light source 40a and reflected from the eye under examination E is captured by the image sensor 13 via the first observation windows 12a, 20a, 23, 24, and 11a. Similarly, reflected light emitted from the second light source 40b and reflected from the eye under examination E is captured by the image sensor 13 via the second observation windows 12b, 20, 23, 24, and 11b. This allows for the acquisition of an image including the corneal apex 82 of the eye under examination E, the aiming scale plate 23, and the reticle plate 24.

[0104] The control unit 70 detects the corneal vertex 82 of the eye under examination E and the scale lines (N1~N5) of the aiming scale plate 23 by analyzing the captured image. For example, edge detection using brightness values ​​may be used as the method for detecting the corneal vertex 82 and the scale lines of the left eye EL. The control unit 70 also detects the scale line to which the corneal vertex 82 of the eye under examination E is in contact. For example, the distance between corneal vertices is associated with each scale line, and a second distance V2 can be obtained based on the scale line. Similarly, for the right eye ER, the image analysis process can be performed to obtain the second distance V2. In the above, the image sensor 13 only needs to be positioned in a location where the second distance V2 can be detected, and is not limited to this embodiment.

[0105] For example, as described above, the optometry device of this embodiment detects the second distance in the subjective measurement of the eye under examination and obtains the second distance based on the detection result. This makes it easy to determine whether the second distance in the subjective measurement matches the first distance in the objective measurement. As a result, the eye under examination can be corrected with an appropriate refractive power based on the first objective refractive power or the second objective refractive power.

[0106] In this embodiment, the configuration described as acquiring the position of the corneal apex 82 of the eye under examination at the start of subjective measurement of the eye under examination E is used as an example, but the system is not limited to this. For example, the configuration may also acquire the position of the corneal apex 82 during subjective measurement of the eye under examination E. For example, the control unit 70 may acquire images captured by the image sensor 13 in real time and notify the system when the position of the corneal apex 82 changes (in other words, when the second distance V2 changes) using a notification unit (not shown). For example, an acceptable range may be provided for detecting whether or not the position of the corneal apex 82 has changed. For example, the notification unit may be at least one of a speaker, buzzer, display, etc. This allows for accurate subjective measurement of the eye under examination E.

[0107] Furthermore, the conversion of the initial value at the start of subjective measurement in this embodiment can also be applied to a space-saving subjective optometry device (see, for example, Japanese Patent Application Publication No. 2019-000346) which has a target presentation unit for presenting the test target to the eye E inside the housing, and in which the target light beam from the target presentation unit is reflected by an optical member and guided outside the housing, and this target light beam reaches the eye via the refractive power measurement unit 50.

[0108] Furthermore, the conversion of initial values ​​at the start of subjective measurement in this embodiment can be applied to so-called self-examinations, where the examiner is not present and the subject performs the subjective measurement themselves. For example, in this case, a subject controller for the subject to input answers may be provided in the subjective optometry device 1 as shown in Figure 1, or a subject controller may be provided in a space-saving subjective optometry device. The following will explain such self-examinations using a space-saving subjective optometry device as an example.

[0109] Figure 11 is an external view of the space-saving subjective optometry device 200. Figure 11(a) is a perspective view of the external appearance of the subjective optometry device 200. Figure 11(b) is an internal side view of the subjective optometry device 200. For example, the subjective optometry device 200 includes a housing 201, a presentation window 202, a speaker 203, a holding unit 204, an examiner controller 210, a subject controller 220, an ocular refractive power measurement unit 240, etc. The ocular refractive power measurement unit 240 has the same configuration as the ocular refractive power measurement unit 50 described above, and its explanation is omitted here.

[0110] The housing 201 has a light projection optical system 230 inside. The display window 202 transmits the target light beam from the light projection optical system 230. The speaker 203 outputs audio guidance, etc. The holding unit 204 holds the eye refractive power measurement unit 240.

[0111] The examiner controller 210 is used by the examiner to operate the subjective ophthalmoscopic examination device 200. The examiner controller 210 includes a switch unit 211, a monitor 212, etc. The switch unit 211 receives signals for various settings (e.g., movement of the ocular refractive power measurement unit 240, etc.). The monitor 212 displays various information (e.g., measurement results of the eye E under examination, etc.). The monitor 212 may also function as a touch panel that also serves as the switch unit 211. Signals from the examiner controller 210 are output to a control unit (not shown) via wired or wireless communication.

[0112] The subject controller 220 is used to input the subject's responses. The subject controller 220 includes a response lever 221, response buttons 222, etc. The response lever 220 is used when the subject inputs the direction relative to the test target. For example, signals for the four directions (up, down, left, and right) can be input by tilting. The response buttons 222 are used when the subject does not select a direction relative to the test target. Signals from the subject controller 220 are output to a control unit (not shown) via wired or wireless communication.

[0113] The light projection optical system 230 (see Figure 11(b)) projects a target light beam toward the eye E under examination. For example, the light projection optical system 230 includes a display 231, a planar mirror 232, a concave mirror 233, etc. The target light beam emitted from the display 231 is guided out of the housing 201 via the planar mirror 232, the concave mirror 233, and the planar mirror 232 in that order, and is further projected onto the eye E under examination via the presentation window 202 and the examination window and optical elements of the refractive power measurement unit 240.

[0114] In such a subjective optometry device 200, initial values ​​are set based on the first objective value of the eye E under examination so that the eye E has a predetermined refractive power (e.g., 0D), and the subjective measurement proceeds automatically when a self-examination application is executed. Here, for example, in self-examination, the subject can start the subjective measurement by placing their face against the forehead rest and then operating the subject controller 220. At this time, the examiner is not always present, and there is a high possibility that the second distance V2 of the subjective measurement will be different from the first distance V1 of the objective measurement. For this reason, especially in self-examination, a discrepancy in the actual refractive power is likely to occur due to the mismatch between the first distance V1 and the second distance V2.

[0115] In this embodiment, the subjective ophthalmoscopic device 200 may also set the initial value for subjective measurement based on the first objective value and first distance V1 of the objective measurement of the eye E under test, and the second distance V2 of the subjective measurement of the eye E under test. For example, the control unit may acquire the second distance V2 by analyzing the captured image using the detection unit (image sensor) provided in the refractive power measurement unit 240. Furthermore, if the first distance V1 and the second distance V2 are different, the first objective value based on the first distance V1 may be converted to a second objective value based on the second distance V2, and this may be set as the initial value for subjective measurement.

[0116] As described above, the optometry device of this embodiment presents a test target to the eye under examination, and after the initial correction value of the correction means is set, it automatically proceeds with subjective measurement based on the input signal from the response input means in which the subject inputs their response to interpreting the test target. For example, in so-called self-optometry, where the subject performs the subjective measurement themselves, it is not easy to match the second distance in subjective measurement with the first distance in objective measurement. As a result, the first and second distances do not match at the start of subjective measurement, and the measurement proceeds with the eye actually corrected with different refractive powers, which could lead to an extension of the measurement time. However, as in this embodiment, when the first and second distances are different, the first objective refractive power based on the first distance is converted to the second objective refractive power based on the second distance and output, so that even in self-optometry, the eye under examination can be correctly corrected with a predetermined refractive power, and subjective measurement can be performed smoothly.

[0117] In this embodiment, a subjective optometry device that subjectively measures the refractive power of the eye under examination is used as an example to explain a configuration in which a first objective value based on a first distance V1 is converted to a second objective value based on a second distance V2. However, the embodiment is not limited to this. For example, an objective optometry device that objectively measures the refractive power of the eye under examination may be configured to convert the first objective value to a second objective value. In this case, the objective optometry device may measure the first objective value at the first distance V1 and receive the second distance V2 from the subjective optometry device, thereby converting the first objective value to a second objective value. [Explanation of Symbols]

[0118] 1. Subjective eye examination device 11 Confirmation window 12 Observation window 30 Suppression Unit 40 light source 50. Refractive power measurement unit 51 Forehead protector 53 Inspection window 55 Lens chamber unit 60 Visual target presentation part 70 Control Unit 100 Objectively Observed Eye Refractive Power Measurement Device 200 Self-aware eye examination device

Claims

1. An optometry device comprising a target presentation means for emitting a target light beam toward the eye to be examined, and a corrective means for changing the optical properties of the target light beam, for subjectively measuring the refractive power of the eye to be examined, An objective refractive power acquisition means for acquiring the objective refractive power of the eye being examined in an objective measurement, A first distance acquisition means for acquiring a first distance from the corneal apex of the eye to the lens fitting reference position in the objective measurement of the eye under examination, A second distance acquisition means for acquiring a second distance from the corneal apex of the eye to the lens fitting reference position in the subjective measurement of the eye under examination, When the first distance and the second distance are different, a conversion means is provided to convert the first objective eye refractive power based on the first distance to the second objective eye refractive power based on the second distance. The output means for outputting the second objectively observed refractive power, An optometry device characterized by being equipped with the following features.

2. In the eye examination device of claim 1, An optometry device characterized by comprising a correction control means for setting an initial correction value for the correction means based on the second objective eye refractive power output from the output means.

3. In the ophthalmoscopic device according to claim 1 or 2, The optometry device is characterized in that the conversion means converts the first objective eye refractive power to the second objective eye refractive power when the first distance and the second distance are different and the first objective eye refractive power exceeds a predetermined threshold.

4. In the eye examination device of claim 1, The system includes a detection means for detecting the second distance in the subjective measurement of the eye under examination, The eye examination device is characterized in that the second distance acquisition means acquires the second distance based on the detection result of the detection means.

5. An eye examination program for use in an eye examination device that includes a target presentation means for emitting a target light beam toward an eye to be examined, and a corrective means for changing the optical properties of the target light beam, wherein the refractive power of the eye to be examined is measured subjectively, By being executed by the processor of the aforementioned ophthalmic device, An objective refractive power acquisition step is performed to acquire the objective refractive power of the eye being examined in an objective measurement, A first distance acquisition step of acquiring a first distance from the corneal apex of the eye to the lens fitting reference position in the objective measurement of the eye to be examined, A second distance acquisition step in which a second distance is obtained from the corneal apex of the eye to the lens fitting reference position in the subjective measurement of the eye to be examined, When the first distance and the second distance are different, a conversion step is made to convert the first objective eye refractive power based on the first distance to the second objective eye refractive power based on the second distance, The output step of outputting the second objective eye refractive power, An eye examination program characterized by causing the eye examination device to perform the following.

6. An optometry device for measuring the refractive power of an eye under examination, An objective refractive power acquisition means for acquiring the objective refractive power of the eye being examined in an objective measurement, A first distance acquisition means for acquiring a first distance from the corneal apex of the eye to the lens fitting reference position in the objective measurement of the eye under examination, A second distance acquisition means for acquiring a second distance from the corneal apex of the eye to the lens fitting reference position in the subjective measurement of the eye under examination, When the first distance and the second distance are different, a conversion means is provided to convert the first objective eye refractive power based on the first distance to the second objective eye refractive power based on the second distance. The output means for outputting the second objectively observed refractive power, An optometry device characterized by being equipped with the following features.

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