Subjective optometer

Abstract

To provide a subjective optometer capable of efficiently proceeding with subjective measurement of an eye to be examined.SOLUTION: A subjective optometer having subjective measuring means for measuring at least eyesight of an eye to be examined by presenting an examination target to the eye to be examined includes: first corrected eyesight value acquisition means for acquiring a first corrected eyesight value, which is a measurement result of measuring the highest eyesight value of the eye to be examined, in a state that eye refractive power of the eye to be examined is corrected by a predetermined correction degree; reference value setting means for setting a reference value for checking propriety of the correction degree for the eye to be examined on the basis of the first corrected eyesight value; second corrected eyesight value acquisition means for acquiring a second corrected eyesight value, which is a measurement result of measuring the eye to be examined using the subjective measuring means, in a state that the eye refractive power of the eye to be examined is corrected by the predetermined correction degree; and control means for executing predetermined control according to the propriety of the correction degree of the eye to be examined on the basis of whether the second corrected eyesight value of the eye to be examined exceeds the reference value.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a subjective optometry device that subjectively measures optical characteristics of a subject's eye. [Background technology]

[0002] 2. Description of the Related Art There is known a subjective optometry device that measures optical characteristics of a subject's eye by placing an optical member in front of the subject's eye and presenting a test target to the subject's eye via the optical member (see Patent Document 1). [Prior art documents] [Patent documents]

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

[0004] In the above-mentioned subjective eye examination device, measurements of a plurality of examination items are performed to adjust the spherical power, cylindrical power, astigmatism axis angle, etc., of the subject's eye. For example, when the subject already wears glasses or contact lenses, measurements of all the examination items may be performed to check whether there is a problem with the current correction power of the subject's eye. In this case, it takes time to complete a series of measurements of the subject's eye, which may be a burden on the examiner and the subject.

[0005] In view of the above problems, the present disclosure has as its technical object to provide a subjective optometry device that can efficiently perform subjective measurement of a subject's eye. [Means for solving the problem]

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

[0007] A subjective eye examination device according to a first aspect of the present disclosure includes a subjective measurement means for measuring at least the visual acuity of the subject's eye by projecting a visual target light beam from a visual target presenting means toward the subject's eye and presenting a test visual target to the subject's eye, and is a subjective eye examination device that subjectively measures optical characteristics of the subject's eye, and includes a first corrected visual acuity value acquisition means for acquiring a first corrected visual acuity value, which is a measurement result of measuring the best visual acuity value of the subject's eye in a state in which the ocular refractive power of the subject's eye is corrected with a predetermined correction power, and a front optical axis for the subject's eye. The device is characterized by comprising a reference value setting means for setting a reference value for confirming the suitability of the corrective power based on the first corrected visual acuity value, a second corrected visual acuity value acquisition means for acquiring a second corrected visual acuity value which is a measurement result of measuring the test eye using the subjective measurement means in a state in which the ocular refractive power of the test eye is corrected with the specified corrective power, and a control means for executing a specified control according to the suitability of the corrective power of the test eye based on whether the second corrected visual acuity value of the test eye exceeds the reference value. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is an external view of a subjective optometry device. [Diagram 2] FIG. 2 is a schematic diagram of a projection optical system. [Diagram 3] FIG. 2 is a schematic diagram of an eye refractive power measuring unit. [Figure 4] FIG. 2 is a schematic diagram of a control system of the subjective optometry device. [Diagram 5] FIG. 11 is a flow chart showing the flow of visual acuity measurement. [Figure 6] 13 is an example of an operation screen. [Figure 7] 13 is an example of an operation screen. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] <Summary> An embodiment of the subjective optometry device according to the present embodiment will be described. The items classified in < > below can be used independently or in conjunction with each other.

[0010] <Means for presenting visual targets> The subjective eye examination apparatus of this embodiment may include a target presenting means for projecting a target light beam toward the eye to be examined in order to present the target to the eye.

[0011] For example, the optotype presenting means may be a display (e.g., display 31). As an example, the display may be an LCD (Liquid Crystal Display), an organic EL (Electro Luminescence) display, or the like. For example, the optotype presenting means may be a light source and an optotype plate. For example, the optotype presenting means may be a light source and a DMD (Digital Micromirror Device).

[0012] For example, the target light beam from the target presenting means may be directly guided toward the subject's eye. Also, for example, the target light beam from the target presenting means may be guided toward the subject's eye via a light projecting optical system (for example, the light projecting optical system 30). For example, the light projecting optical system may have at least one optical member through which the target light beam emitted from the target presenting means passes. As an example, it may have at least one of a lens, a mirror, and the like.

[0013] <Subjective measurement method> The subjective eye examination device of this embodiment may include a subjective measurement means. For example, the subjective measurement means may be a subjective measurement means for measuring at least the visual acuity of the subject's eye by presenting a test target to the subject's eye. Note that, for example, the subjective measurement means may be a subjective measurement means for subjectively measuring the optical characteristics of the subject's eye as well as the visual acuity of the subject's eye. For example, the optical characteristics of the subject's eye may be ocular refractive power (e.g., spherical power, cylindrical power, cylindrical axis angle, etc.), contrast sensitivity, binocular vision function (e.g., strabismus amount, stereoscopic vision function, etc.), etc.

[0014] For example, the subjective measurement means may include a light projection optical system (e.g., the light projection optical system 30). For example, the light projection optical system projects a visual target light beam toward the subject's eye. The light projection optical system may have at least one optical member that guides the visual target light beam toward the subject's eye.

[0015] For example, the subjective measuring means may include a correcting means (e.g., a control unit 60). For example, the correcting means changes the optical characteristics of the visual target light beam emitted from the visual target presenting means. For example, the optical characteristics of the visual target light beam may be at least one of the spherical power, cylindrical power, and astigmatism axis angle of the visual target light beam. For example, the correcting means may include a corrective optical system as a part of the configuration of the correcting means. For example, the corrective optical system is disposed in the optical path of the light projection optical system and changes the optical characteristics of the visual target light beam.

[0016] For example, the correction optical system may be configured to change the optical characteristics of the visual target light beam. For example, the correction optical system may change the spherical power of the visual target light beam by optically changing the presentation distance of the visual target with respect to the eye to be examined. Also, for example, the correction optical system may change at least one of the spherical power, cylindrical power, astigmatism axis angle, etc. of the visual target light beam by controlling the optical element. As an 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 optical elements. Note that the correction optical system may be configured by combining a configuration for changing the presentation distance of the visual target with a configuration for controlling the optical element.

[0017] For example, the correction optical system may be an eye refraction measuring unit (e.g., eye refraction measuring unit 40) that places an optical element in front of the eye to be examined. For example, the eye refraction measuring unit may have a variable focus lens and change the refractive power of the variable focus lens. Also, for example, the eye refraction measuring unit may have a lens disk on which a plurality of optical elements are arranged on the same circumference, and a driving means (e.g., a motor) for rotating the lens disk, and the optical elements may be electrically switched by driving the driving means. Of course, the eye refraction measuring unit may have a variable focus lens, a lens disk, and a driving means.

[0018] Also, for example, the correction optical system may be configured to change the optical characteristics of the visual target light beam by controlling an optical element disposed between the visual target presenting means and an optical member for guiding the visual target light beam emitted from the visual target presenting means. That is, the correction optical system may be configured as a phantom lens refractometer (phantom correction optical system).

[0019] <First corrected visual acuity value acquisition means> The subjective eye examination device of this embodiment may include a first corrected visual acuity value acquiring means (for example, the control unit 60). For example, the first corrected visual acuity value acquiring means acquires a first corrected visual acuity value, which is a measurement result of measuring the best visual acuity value of the eye to be examined in a state where the eye refractive power of the eye to be examined is corrected with a predetermined correction power. For example, the predetermined correction power of the eye to be examined may be a correction power previously prescribed for the eye to be examined. As an example, it may be a power of a spectacle lens or a contact lens determined based on a subjective measurement performed on the eye to be examined in a state where the eye is naked. As another example, it may be a power of a spectacle lens or a contact lens determined based on a subjective measurement performed on the eye to be examined in a state where the eye is wearing a spectacle lens or a contact lens. In addition, the state where the eye to be examined is corrected with a predetermined correction power may be a state where the eye to be examined is corrected with a predetermined correction power by a correcting means, or a state where the eye to be examined is corrected with a predetermined correction power by a spectacle lens or a contact lens.

[0020] For example, the first corrected visual acuity value acquiring means may acquire past (previous) subjective measurement data (pre-subjective measurement data) acquired by subjectively measuring the optical characteristics of the subject's eye. For example, the pre-subjective measurement data may include at least the highest visual acuity value. Of course, for example, the pre-subjective measurement data may include ocular refractive power data (for example, at least one of spherical refractive power, cylindrical refractive power, astigmatism axis angle, etc.), polarization characteristic data, interpupillary distance, etc.

[0021] For example, the first corrected visual acuity value acquisition means may acquire pre-subjective measurement data input by the examiner operating an operation means (e.g., examiner controller 10). Also, for example, the first corrected visual acuity value acquisition means may read an identifier for each subject and acquire the pre-subjective measurement data stored in the identifier. As an example, the identifier may be an ID, a character string, a one-dimensional code, a two-dimensional code, a color code, or the like. Also, for example, the first corrected visual acuity value acquisition means may acquire the pre-subjective measurement data by receiving data measured using a device other than the subjective eye examination device of this embodiment.

[0022] <Method of setting reference value> The subjective eye examination device of this embodiment may include a reference value setting means (for example, the control unit 60). For example, the reference value setting means may set a reference value for checking whether the correction power for the subject's eye is appropriate based on the first corrected visual acuity value. For example, the reference value setting means may set a reference value for checking whether the correction power given to the subject by the current eyeglass lenses or contact lenses is appropriate based on the first corrected visual acuity value. For example, this makes it possible to easily determine whether the current correction power is appropriate for the current eye even after a period of time has passed since eyeglasses or contact lenses were prescribed for the eye. In addition, it is possible to easily grasp whether the ocular refractive power of the eye has changed depending on whether the current correction power of the eye is appropriate.

[0023] For example, the reference value setting means may set a value equal to the first corrected visual acuity value or a value around the first corrected visual acuity value as a reference value for checking the suitability of the correction power for the eye to be examined. For example, the value around the first corrected visual acuity value may be a value higher (larger) than the first corrected visual acuity value. For example, in this case, the value around the first corrected visual acuity value may be a visual acuity value that is a predetermined step higher than the first corrected visual acuity value. As an example, if the first corrected visual acuity value is 1.0, the value around the first corrected visual acuity value may be 1.2, which is one step higher. Of course, the predetermined step may be different from one step. Also, for example, the value around the first corrected visual acuity value may be a value lower (smaller) than the first corrected visual acuity value. For example, in this case, the value around the first corrected visual acuity value may be a visual acuity value that is a predetermined step lower than the first corrected visual acuity value. As an example, if the first corrected visual acuity value is 1.0, the value around the first corrected visual acuity value may be 0.9, which is one step lower. Of course, the predetermined step may be different from one step. For example, the values ​​around the first corrected visual acuity value may be set as values ​​having an allowable range for the first corrected visual acuity value.

[0024] <Measuring range setting method> The subjective optometry device of this embodiment may include a measurement range setting means (e.g., a control unit 60). For example, the measurement range setting means may set a measurement range for changing the visual acuity value of a test optotype presented to the subject's eye based on the first corrected visual acuity value when the subject's eye is measured by the subjective measurement means. For example, the measurement range for changing the visual acuity value of a test optotype presented to the subject's eye may be different for the left eye and the right eye. Also, for example, the measurement range for changing the visual acuity value of a test optotype presented to the subject's eye may be the same for the left eye and the right eye. As an example, in this case, between the measurement range set based on the first corrected visual acuity value of the left eye and the measurement range set based on the first corrected visual acuity value of the right eye, a wider measurement range may be applied as the measurement range for the left eye and the right eye.

[0025] For example, when the measurement range setting means sets a measurement range for changing the visual acuity value of the test target, the subjective measurement means may change the visual acuity value of the test target based on the measurement range set by the measurement range setting means. This makes it possible to shorten the measurement time required for subjective measurement of the subject's eye.

[0026] For example, the measurement range setting means may set the highest visual acuity value in the measurement range in which the visual acuity value of the test optotype presented to the subject's eye is changed as the upper limit of the measurement range. For example, the upper limit of the measurement range in which the visual acuity value of the test optotype is changed may be the same value as a reference value for checking whether the correction power of the subject's eye is appropriate. Also, for example, the upper limit of the measurement range in which the visual acuity value of the test optotype is changed may be a value different from the reference value for checking whether the correction power of the subject's eye is appropriate. In this case, the upper limit may be a value higher (larger) than the reference value.

[0027] For example, when the upper limit of the measurement range for changing the visual acuity value of the test optotype is set by the measurement range setting means, the subjective measurement means may change the visual acuity value of the test optotype from low to high based on the measurement range set by the measurement range setting means, and may end the measurement when the visual acuity value reaches the upper limit. This allows the measurement to be performed by taking into consideration in advance the highest visual acuity value among the visual acuity values ​​at which the test eye can recognize the test optotype without any problems, and it is possible to omit the presentation of the visual acuity value of the test optotype that the test eye cannot recognize. Therefore, the measurement time required for the subjective measurement of the test eye is shortened.

[0028] For example, the measurement range setting means may set the lowest visual acuity value in the measurement range in which the visual acuity value of the test optotype presented to the subject's eye is changed as the lower limit of the measurement range. For example, the lower limit of the measurement range in which the visual acuity value of the test optotype is changed may be the same value as the reference value for checking whether the correction power of the subject's eye is appropriate. Also, for example, the lower limit of the measurement range in which the visual acuity value of the test optotype is changed may be a value different from the reference value for checking whether the correction power of the subject's eye is appropriate. In this case, the upper limit may be a value lower (smaller) than the reference value.

[0029] For example, when the measurement range setting means sets the lower limit of the measurement range in which the visual acuity value of the test optotype is changed, the subjective measurement means may change the visual acuity value of the test optotype from the lower limit to the higher visual acuity value based on the measurement range set by the measurement range setting means. This allows the measurement to be performed taking into consideration in advance the lowest visual acuity value among the visual acuity values ​​at which the test eye can recognize the test optotype without any problems, and makes it possible to omit the presentation of the visual acuity value of the test optotype that the test eye cannot recognize. Therefore, the measurement time required for the subjective measurement of the test eye is shortened.

[0030] For example, the measurement range setting means may set both the upper and lower limits of the measurement range for changing the visual acuity value of the test optotype presented to the subject's eye. In this case, the subjective measurement means may change the visual acuity value of the test optotype from the lower limit to the upper limit based on the measurement range set by the measurement range setting means, and may end the measurement when the visual acuity value reaches the upper limit. This allows the measurement to be performed by taking into consideration in advance the highest visual acuity value and the lowest visual acuity value among the visual acuity values ​​at which the subject's eye is considered to be able to recognize the test optotype without any problems, and the measurement time required for the subjective measurement of the subject's eye is further shortened.

[0031] <Means for acquiring second corrected visual acuity value> The subjective eye examination device of this embodiment may include a second corrected visual acuity value acquiring means (e.g., the control unit 60). For example, the second corrected visual acuity value acquiring means may acquire a second corrected visual acuity value, which is a measurement result obtained by measuring the subject's eye using a subjective measuring means in a state in which the ocular refractive power of the subject's eye is corrected with a predetermined corrected visual acuity value. For example, the state of the corrected visual acuity when the first corrected visual acuity value of the subject's eye is acquired and the state of the corrected visual acuity when the second corrected visual acuity value of the subject's eye is acquired may be the same state.

[0032] For example, the second corrected visual acuity value acquiring means may acquire current (present) subjective measurement data acquired by subjectively measuring the optical characteristics of the subject's eye. For example, the subjective measurement data may include at least the highest visual acuity value. Of course, for example, the subjective measurement data may include eye refractive power data (for example, at least one of spherical refractive power, cylindrical refractive power, astigmatism axis angle, etc.), polarization characteristic data, interpupillary distance, etc.

[0033] <Control means> The subjective eye examination device of this embodiment may include a control means (e.g., a control unit 60). For example, the control means may control the optotype presenting means. As an example, the control means may control the display of the optotype presenting means, and change at least one of the type of optotype, the visual acuity value of the optotype, etc. Also, for example, the control means may control the correction means. As an example, the control means may change at least one of the presentation distance of the optotype by the correction means (for example, the movement of the optotype presenting means), the arrangement of the optical elements in the correction means, etc. Of course, for example, the control means may combine such control of the optotype presenting means and the correction means.

[0034] For example, the control means may execute a predetermined control according to the appropriateness of the correction power of the test eye based on whether the second corrected visual acuity value of the test eye exceeds the reference value. For example, the control means may compare the second corrected visual acuity value of the test eye with the reference value, and execute a predetermined control according to the appropriateness of the correction power of the test eye based on the comparison result. Also, for example, the control means may compare the second corrected visual acuity value of the test eye with the reference value, determine whether the second corrected visual acuity value matches the reference value based on the comparison result, and execute a predetermined control according to the appropriateness of the correction power of the test eye based on the determination result. For example, by grasping the appropriateness of the current correction power of the test eye and executing a control according to the appropriateness, the subjective measurement of the test eye can be efficiently carried out.

[0035] For example, the control means may execute a guidance process for guiding the next action corresponding to the correction power of the subject's eye as a predetermined control according to whether the correction power of the subject's eye is appropriate. For example, the guidance process for guiding the next action corresponding to the correction power of the subject's eye may be a guidance process for guiding an action to be performed by the subjective optometry device. Also, for example, the guidance process for guiding the next action corresponding to the correction power of the subject's eye may be a guidance process for guiding an action to be performed by the examiner.

[0036] For example, the guidance process for guiding the operation performed by the subjective optometry device may be a process for automatically terminating the subjective measurement of the subject's eye. For example, in this case, when the corrective power of the subject's eye is appropriate, the subjective measurement may be terminated. Also, for example, the guidance process for guiding the operation performed by the subjective optometry device may be a process for shifting the process of the subjective measurement of the subject's eye. As an example, it may be a process for shifting the subjective measurement to the addition of a spherical power, which will be described later. For example, in this case, the process may shift to the addition of a spherical power at least either when the corrective power of the subject's eye is appropriate or when it is not appropriate. Also, as an example, it may be a process for shifting the subjective measurement to the implementation of a self-optometry program. For example, in this case, the process may shift to the implementation of a self-optometry program when the corrective power of the subject's eye is not appropriate.

[0037] For example, the guidance process for guiding the action performed by the examiner may be a process of outputting guide information indicating the next action of the examiner. For example, the guide information may be information for indicating an action to be performed by the examiner on the subjective measurement device. As an example, the guide information may be information that prompts the examiner to perform at least one of the following: ending the subjective measurement of the eye to be examined, adding a spherical power to the eye to be examined, and performing a self-eye examination program on the eye to be examined. In addition, for example, the guide information may be information for supporting the examiner in making a judgment on the correction power of the eye to be examined. As an example, the guide information may be information that notifies the examiner that the correction power of the eye to be examined needs to be changed, information that notifies the examiner that the correction power of the eye to be examined does not need to be changed, and the like. Note that, for example, the same guide information may be output when the correction power of the eye to be examined is appropriate and when it is not appropriate, or different guide information may be output.

[0038] For example, the guide information may be displayed as a message on a display means. Also, for example, the guide information may be generated as a voice guide by a voice generating means (for example, a speaker). Also, for example, the guide information may be displayed by lighting or blinking of a notification means (for example, a lamp).

[0039] For example, the control means may perform a predetermined control according to the suitability of the correction power of the test eye, and then control the correction means to add spherical power to the predetermined correction power while the ocular refractive power of the test eye is corrected with the predetermined correction power.

[0040] For example, the control means may add a spherical power to the predetermined correction power of the test eye when the second corrected visual acuity value of the test eye is the same as the reference value. As an example, the control means may add a spherical power so as to weaken the predetermined correction power of the test eye. For example, in this case, the second corrected visual acuity value acquisition means may again acquire the second corrected visual acuity value in a state in which the eye refractive power of the test eye is corrected with a correction power different from the predetermined correction power. As an example, the second corrected visual acuity value may again be acquired in a state in which the eye refractive power of the test eye is corrected with a correction power weaker than the predetermined correction power. For example, this makes it easy to check whether the test eye is in an overcorrected state.

[0041] Also, for example, the control means may add a spherical power to the predetermined corrective power of the test eye when the second corrected visual acuity value of the test eye does not meet the reference value. As an example, the control means may add a spherical power so as to strengthen the predetermined corrective power of the test eye. For example, in this case, the second corrected visual acuity value acquisition means may again acquire the second corrected visual acuity value in a state in which the eye refractive power of the test eye is corrected with a corrective power different from the predetermined corrective power. As an example, the second corrected visual acuity value may again be acquired in a state in which the eye refractive power of the test eye is corrected with a corrective power stronger than the predetermined corrective power. For example, this makes it possible to easily grasp an appropriate corrective power taking into account the deterioration of the visual acuity of the test eye.

[0042] For example, the control means may automatically execute a self-eye examination program including a plurality of examination items for the subject's eye as a predetermined control according to whether the correction power of the subject's eye is appropriate. As an example, the control means may execute the self-eye examination program when the correction power of the subject's eye is not appropriate.

[0043] The subjective eye examination device of this embodiment may have a first measurement mode in which at least the optotype presenting means is controlled based on the answer input by the examinee to automatically proceed with an eye examination program for checking whether the correction power of the eye to be examined is appropriate, and a second measurement mode in which at least one of the optotype presenting means and the correction means is controlled based on the answer input by the examinee to automatically proceed with a self-eye examination program including a plurality of examination items for the eye to be examined. For example, in this case, the control means may execute a switch from the first measurement mode to the second measurement mode as a predetermined control according to whether the correction power by executing the first measurement mode is appropriate, and proceed with the measurement according to the procedure of the self-eye examination program. As a result, for example, if the current correction power of the eye to be examined is not appropriate, the device may shift to a self-eye examination, and a more detailed eye examination may be performed, including changing the correction power of the eye to be examined and obtaining a corrected visual acuity value associated with the change in the correction power of the eye to be examined. Therefore, for example, the examiner can easily determine the next correction power of the eye to be examined by using the result of the self-eye examination of the eye to be examined.

[0044] <Example> An example of a subjective optometry device according to the present embodiment will be described. In this example, a subjective optometry device for subjectively measuring the optical characteristics of a subject's eye is illustrated, which is integrally equipped with a display for displaying a test target on the subject's eye and an eye refractive power measuring unit for changing the optical characteristics of the target light beam emitted from the display. Of course, for example, the display may be provided as a separate housing from the subjective optometry device.

[0045] <Apparatus appearance> Fig. 1 is an external view of a subjective optometry device 100. Fig. 1(a) shows a state in which an eye refraction measurement unit 40 is supported in a standby position. Fig. 1(b) shows a state in which the eye refraction measurement unit 40 is supported in a measurement position. For example, the subjective optometry device 100 includes a housing 1, a presentation window 2, a speaker 3, a holding unit 4, an examiner controller 10, a subject controller 20, an eye refraction measurement unit 40, and the like.

[0046] The housing 1 has a light projection optical system 30 inside. The presentation window 2 transmits the visual target light beam from the light projection optical system 30. The visual target light beam is projected onto the subject's eye E through the presentation window 2. When an eye refractive power measuring unit 40 is disposed between the subject's eye E and the presentation window 2 (see FIG. 1(b)), the visual target light beam is projected onto the subject's eye E through the presentation window 2 and a test window 43 described below. This presents a test visual target to the subject's eye E. The speaker 3 outputs audio guidance and the like.

[0047] The holding unit 4 holds the eye refraction measuring unit 40. For example, the holding unit 4 moves an arm by driving a driving unit (motor or the like) not shown, thereby moving the eye refraction measuring unit 40 connected to the arm. This allows the eye refraction measuring unit 40 to be switched between a standby position and a measurement position.

[0048] The examiner's controller 10 is used by the examiner to operate the subjective optometry device 100. The examiner's controller 10 includes a switch section 11, a monitor 12, and the like. The switch section 11 inputs signals for performing various settings (e.g., moving the eye refractive power measuring unit 40, etc.). The monitor 12 displays various information (e.g., the test results of the subject's eye E, etc.). The monitor 12 may function as a touch panel that also serves as the switch section 11. Signals from the examiner's controller 10 are output to the control section 60 by wired or wireless communication.

[0049] The subject controller 20 is used to input the subject's answer. The subject controller 20 includes an answer lever 21, an answer button 22, and the like. The answer lever 21 is used by the subject when inputting a direction relative to the test target. For example, signals in four directions, up, down, left, and right, can be input by tilting. The answer button 22 is used by the subject when he or she does not select a direction relative to the test target. The signal from the subject controller 20 is output to the control unit 60 by wired or wireless communication.

[0050] <Projection optical system> Fig. 2 is a schematic diagram of the light projection optical system 30. Fig. 2(a) shows the optical arrangement during a distance test. Fig. 2(b) shows the optical arrangement during a near test. The light projection optical system 30 projects a visual target light beam toward the subject's eye E. For example, the light projection optical system 30 includes a display 31, a plane mirror 32, a concave mirror 33, a near / far switcher 34, and the like.

[0051] The display 31 displays a visual target (e.g., a fixation target, a test visual target, etc.). A visual target light beam emitted from the display 31 forms an image on the fundus of the subject's eye E, thereby presenting the visual target to the subject's eye E. For example, the display 31 may be an LCD (Liquid Crystal Display), an organic EL (Electro Luminescence), a plasma display, etc.

[0052] The display 31 may include a polarizing optical member. For example, a polarizing optical member may be disposed in front of the display 31, or a polarizing optical member may be incorporated and disposed integrally in the display 31. This enables the display 31 to emit linearly polarized light or circularly polarized light polarized in a predetermined direction (vertical, horizontal, or 45-degree diagonal, etc.).

[0053] The plane mirror 32 reflects the visual target light beam from the display 31 and guides it to the concave mirror 33. The plane mirror 32 also reflects the visual target light beam from the display 31 and guides it to the subject's eye E. For example, the plane mirror 32 is disposed so that the distance (presentation distance) from the subject's eye E to the display 31 during a near vision test of the subject's eye E is optically 40 cm. Note that instead of the plane mirror 32, it is also possible to use a reflecting member such as a prism, a beam splitter, or a half mirror.

[0054] The concave mirror 33 reflects the visual target light beam from the display 31 and guides it to the plane mirror 32. For example, the concave mirror 33 is disposed so that the distance (presentation distance) from the subject's eye E to the display 31 during a distance test of the subject's eye E is optically 5 m. Note that instead of the concave mirror 33, it is also possible to use a reflective member such as an aspheric mirror or a free-form mirror. Also, instead of the concave mirror 33, it is also possible to use a lens or the like.

[0055] The far / near switching unit 34 switches the arrangement of the display 31 between a distance test and a near test of the subject's eye E. For example, the far / near switching unit 34 moves the holding unit by driving a drive unit (motor or the like) not shown, thereby moving the display 31 held by the holding unit. This allows the display 31 to be switched between a distance arrangement and a near arrangement.

[0056] For example, during a distance test of the subject's eye E, the display screen of the display 31 is directed toward the back of the housing 1 (see FIG. 2(a)). The visual target light beam from the display 31 passes through the optical axis L1 and enters the plane mirror 32, where it is reflected in the direction of the optical axis L2. It also passes through the optical axis L2 and enters the concave mirror 33, where it is reflected in the direction of the optical axis L3. It also passes through the optical axis L3 and enters the plane mirror 32, where it is reflected in the direction of the optical axis L4. As a result, the visual target light beam that has passed through each optical member inside the housing 1 and is emitted to the outside of the housing 1 is projected onto the subject's eye E.

[0057] For example, during a near vision test of the subject's eye E, the display screen of the display 31 is directed toward the upper surface of the housing 1 (see FIG. 2(b)). The visual target light beam from the display 31 passes through the optical axis L3 and enters the plane mirror 32, and is reflected by the plane mirror 32 in the direction of the optical axis L4. As a result, the visual target light beam that has passed through each optical member inside the housing 1 and is emitted to the outside of the housing 1 is projected onto the subject's eye E.

[0058] <Eye refractive power measurement unit (corrective optical system)> 3 is a schematic diagram of the eye refraction measuring unit 40. The eye refraction measuring unit 40 subjectively measures the refractive power of the subject's eye E. The eye refraction measuring unit 40 is also used as a correction optical system. The correction optical system is disposed in the optical path of the projection optical system 30, and changes the optical characteristics of the visual target light beam. For example, the eye refraction measuring unit 40 includes a forehead rest 41, a lens unit 42, an examination window 43, a moving unit 44, and the like.

[0059] The forehead rest 41, against which the subject's head rests, fixes the subject's eye E at a predetermined examination position and maintains a constant distance from the subject's eye E to the examination window 43. The lens unit 42 has a pair of left and right lens units 42L and 42R. The lens unit 42 has an examination window 43 (a left examination window 43L and a right examination window 43R).

[0060] The moving unit 44 adjusts the distance between the left lens unit 42L and the right lens unit 42R and the convergence angle (inward angle) between the left lens unit 42L and the right lens unit 42R. For example, the moving unit 44 adjusts the distance between the left lens unit 42L and the right lens unit 42R by driving the driving unit 45 (left driving unit 45L and right driving unit 45R). Also, for example, the moving unit 44 adjusts the convergence angle between the left lens unit 42L and the right lens unit 42R by driving the driving unit 46. For a detailed configuration of the moving unit 44, please refer to, for example, Japanese Patent Application Laid-Open No. 2004-329345.

[0061] The lens unit 42 includes a lens disk 50 therein. The lens disk 50 has a pair of left and right lens disks, a left lens disk 50L and a right lens disk 50R. The lens disk 50 is rotated by driving a drive unit 51 (left drive unit 51L and right drive unit 51R). The lens disk 50 also has an opening (or a 0D lens) and a plurality of optical elements 52 (left optical element 52L and right optical element 52R) arranged on the same circumference. These optical elements are rotated by driving a drive unit 53 (left drive unit 53L and right drive unit 53R). As a result, the desired optical element 52 is switched and positioned in the inspection window 43 at the desired angle.

[0062] The lens disk 50 is composed of one lens disk or multiple lens disks. For example, a spherical lens disk, a cylindrical lens disk, an auxiliary lens disk, etc. may be provided. As an example, the spherical lens disk may have multiple spherical lenses with different spherical powers (spherical refractive powers). Also, as an example, the cylindrical lens disk may have multiple cylindrical lenses with different cylindrical powers (cylindrical refractive powers). Also, as an example, the auxiliary lens disk may have a shielding plate, a polarizing lens (polarizing lenses 54L and 54R), a red filter / green filter, a dispersion prism, a Maddox lens, a rotary prism, a cross cylinder lens, an auto cross cylinder lens, a positioning lens, etc. The driving unit 51 and the driving unit 53 may be provided for each lens disk.

[0063] The eye refractive power measuring unit 40 may be configured to change the optical characteristics of the visual target light beam. For example, as in this embodiment, the eye refractive power measuring unit 40 may be configured to control an optical element. Also, for example, the eye refractive power measuring unit 40 may be configured to control a wavefront modulation element.

[0064] <Control Unit> 4 is a schematic diagram of a control system of the subjective optometry device 100. For example, the control unit 60 includes a CPU (processor), a RAM, a ROM, etc. For example, the CPU controls each component in the subjective optometry device 100. For example, the RAM temporarily stores various information. For example, the ROM stores various programs for controlling the operation of the subjective optometry device 100, test target data, etc. The control unit 60 may be composed of multiple control units (i.e., multiple processors).

[0065] The control unit 60 is connected to the speaker 3, the display 31, the examiner's controller 10, a non-volatile memory 70 (hereinafter, memory 70), etc. Also connected to the control unit 60 are a drive unit for the holding unit 4, a drive unit for the near / far switching unit 34, a drive unit for the eye refractive power measuring unit 40 (drive units 45, 46, 51, 53), etc.

[0066] The memory 70 is a non-transient storage medium that can retain stored contents even if the power supply is cut off. For example, the memory 70 may be a hard disk drive, a flash ROM, a USB memory, or the like.

[0067] <Control action> The control operation in the subjective optometry apparatus 100 having the above-mentioned configuration will be described.

[0068] In this embodiment, a subjective measurement of the subject's eye E is performed after the eye refractive power of the subject's eye E has been corrected to a predetermined correction power. For example, the subject wears contact lenses that were previously prescribed, and both the left and right eyes are corrected to a spherical power of -2.00D, a cylindrical power of 0.00D, and an astigmatism axis angle of 0 degrees. For example, the examiner performs a subjective measurement of the subject's eye to check whether there is any problem if the power of the contact lenses to be newly prescribed to the subject this time remains the same as that of the contact lenses previously prescribed.

[0069] The examiner operates the examiner's controller 10 to operate a switch (not shown) for lowering the eye refraction measuring unit 40. For example, the control unit 60 drives the drive unit of the holding unit 4 based on an operation signal from the examiner's controller 10 to move the eye refraction measuring unit 40 to the examination position (see FIG. 1(a)). The examiner also operates the examiner's controller 10 to operate a switch (not shown) for rotating the lens disc 50. For example, the control unit 60 drives the drive unit 51 based on an operation signal from the examiner's controller 10 to position the opening (0D lens) in the examination window 43. For example, the display 31 is placed in the far-distance position, and a far-distance examination of the examinee's eye is performed.

[0070] <Aligning the subject's eye> The examiner aligns the position of the subject's eye E with respect to the eye refraction measuring unit 40. For example, the examiner instructs the subject to place his / her face against the forehead rest 41 and look into the examination window 43. The subject looks into the examination window 43 according to the examiner's instructions.

[0071] The examiner adjusts the position of the forehead rest 41 by operating a forehead rest adjustment knob (not shown) so that the corneal vertex distance of the subject's eye becomes a predetermined distance (e.g., 12 mm). The examiner also operates the examiner's controller 10 to input the interpupillary distance of the subject's eye E. For example, the control unit 60 drives the drive unit 45 based on an operation signal from the examiner's controller 10 to adjust the distance between the left and right lens units 42 and change the distance of the examination window 43 to match the interpupillary distance of the subject's eye. This completes the alignment of the subject's eye E.

[0072] <Obtaining the first corrected visual acuity value of the test eye> Next, the examiner uses the subject ID to input the corrected visual acuity value (first corrected visual acuity value) of the subject's eye E in the previous subjective measurement. For example, the first corrected visual acuity value of the subject's eye is a measurement result obtained by measuring the best visual acuity value of the subject's eye in a state where the ocular refractive power of the subject's eye is corrected with a predetermined correction power. In this embodiment, the first corrected visual acuity value is a measurement result obtained by measuring the best visual acuity value of the subject's eye in a state where the ocular refractive power of the subject's eye is corrected with the correction power (spherical power -2.00D, cylindrical power 0.00D, astigmatism axis angle 0 degrees) determined at the time of the previous contact lens prescription.

[0073] The examiner operates the examiner controller 10 to input the subject ID. For example, the control unit 60 calls up the first corrected visual acuity value corresponding to the subject ID from the memory 70 based on an operation signal from the examiner controller 10. For example, the subject ID is associated with the corrective power determined at the time of the previous contact lens prescription for the subject's eye and the highest visual acuity value (first corrected visual acuity value), and these are stored in advance in the memory 70. In this way, the first corrected visual acuity value in the previous subjective measurement of the subject's eye is obtained. Note that here, a case where the first corrected visual acuity value of both the left and right eyes is 1.0 is illustrated as an example.

[0074] <Setting the reference value> When the first corrected visual acuity value in the previous subjective measurement of the subject's eye is acquired, a reference value in the current subjective measurement of the subject's eye is set. For example, the reference value in the current subjective measurement of the subject's eye is a value for confirming whether a predetermined correction power is appropriate for the subject's eye. In other words, it is a value for confirming whether it is appropriate to correct the ocular refractive power of the subject's eye with the correction power (spherical power -2.00D, cylindrical power 0.00D, astigmatism axis angle 0 degrees) determined in the previous contact lens prescription.

[0075] For example, the control unit 60 sets a reference value for the current subjective measurement of the subject's eye based on the first corrected visual acuity value of the subject's eye. For example, the control unit 60 sets the first corrected visual acuity value of the subject's eye or a value around the first corrected visual acuity value of the subject's eye as the reference value. For example, when a value around the first corrected visual acuity value of the subject's eye is set as the reference value, an arbitrary value based on the first corrected visual acuity value (for example, a visual acuity value one step larger than the first corrected visual acuity value, etc.) may be set in advance.

[0076] In this embodiment, the control unit 60 sets the same value as the first corrected visual acuity value of the subject's eye as the reference value for the current subjective measurement of the subject's eye. That is, the reference values ​​for both the left and right eyes are set to 1.0.

[0077] <Setting the measurement range of visual acuity values> When the reference value for the current subjective measurement of the subject's eye is set, a measurement range is set in which the visual acuity value of the test optotype presented to the subject's eye is changed during the subjective measurement of the subject's eye. For example, in the measurement range in which the visual acuity value of the test optotype presented to the subject's eye is changed, the highest visual acuity value is set as the upper limit of the measurement range. Also, for example, in the measurement range in which the visual acuity value of the test optotype presented to the subject's eye is changed, the lowest visual acuity value is set as the lower limit of the measurement range.

[0078] For example, the control unit 60 sets a measurement range in which the visual acuity value of the test target is changed based on the first corrected visual acuity value of the subject's eye. For example, the control unit 60 may set an upper limit value of the measurement range based on the first corrected visual acuity value of the subject's eye. Also, for example, the control unit 60 may set a lower limit value of the measurement range based on the first corrected visual acuity value of the subject's eye. Of course, for example, the control unit 60 may set the upper limit value and the lower limit value of the measurement range based on the first corrected visual acuity value of the subject's eye.

[0079] In this embodiment, the control unit 60 sets the upper limit and the lower limit of the measurement range for changing the visual acuity value of the test optotype. For example, the control unit 60 sets the same value as the first corrected visual acuity value of the test eye as the upper limit of the measurement range. That is, the upper limit of the measurement range is set to 1.0 for both the left and right eyes. Also, for example, the control unit 60 sets the lower limit of the measurement range to a value that is a predetermined step lower than the first corrected visual acuity value of the test eye. As an example, the control unit 60 sets the lower limit of the measurement range to a value that is two steps lower than the first corrected visual acuity value of the test eye. That is, the lower limit of the measurement range is set to 0.8 for both the left and right eyes.

[0080] That is, in this embodiment, the measurement range for changing the visual acuity value of the test target presented to the subject's eye during subjective measurement of the subject's eye is set to a measurement range from visual acuity value 0.8 to visual acuity value 1.0 for both the left and right eyes. Of course, the measurement range may be different from that in this embodiment, and the examiner may be allowed to arbitrarily set the upper and lower limits.

[0081] <Subjective measurement> When the examiner completes the alignment of the subject's eye and inputs the first corrected visual acuity value of the subject's eye, the examiner starts a subjective measurement of the subject's eye. For example, the examiner sets a first measurement mode to which an eye examination program for checking the appropriateness of the correction power of the subject's eye is applied, and automatically proceeds with the subjective measurement. For example, here, visual acuity measurement is performed following a voice guide.

[0082] The flow of visual acuity measurement of the subject's eye will be described in detail below with reference to the flowchart in Fig. 5. The subject's eye is corrected to a predetermined correction power by a contact lens, and the test target is observed through a test window 43 in which an opening of a lens disk 50 is disposed. For example, when measuring the visual acuity of the left eye (measurement eye), the test window of the right eye (non-measurement eye) is covered.

[0083] At the start of visual acuity measurement of the left eye, the control unit 60 generates audio guidance from the speaker 3, which indicates how to operate the subject's controller 20. The subject observes the test optotype following the audio guidance, and operates the answer lever 21 or answer button 22 of the subject's controller 20. The control unit 60 changes the visual acuity value of the test optotype based on the operation signal from the subject's controller 20, and proceeds with the visual acuity measurement. The visual acuity value of the test optotype can be switched within the range from the upper limit value to the lower limit value set in <Setting the measurement range of visual acuity value>.

[0084] First, the control unit 60 sets the visual acuity value (start value) of the test optotype to be first presented to the left eye (step S1). For example, the control unit 60 sets the lower limit value of the measurement range of the visual acuity value of the test optotype described above as the start value. Also, for example, the control unit 60 calls up test optotype data corresponding to the start value of the test optotype from the memory 70 and displays it on the display 31 (step S2). In this embodiment, a Landolt ring optotype with a visual acuity value of 0.8 is displayed on the display 31.

[0085] Next, the control unit 60 checks whether the left eye can recognize the test optotype (step S3). For example, the control unit 60 generates an audio guide from the speaker 3 asking the subject about the direction of the gap in the Landolt ring optotype, and determines whether the subject's answer is correct or incorrect based on an operation signal from the subject controller 20. For example, the control unit 60 may determine that the subject can recognize the test optotype if the subject answers correctly. Also, for example, the control unit 60 may determine that the subject cannot recognize the test optotype if the subject answers incorrectly. Note that, for example, if the subject answers incorrectly (step S3: NO), the visual acuity measurement of the left eye may be terminated.

[0086] For example, when the subject answers correctly (step S3: YES), the control unit 60 switches the visual acuity value of the test target presented to the left eye from the starting value to a visual acuity value one step higher (here, visual acuity value 0.9) (step S4). Also, for example, the control unit 60 causes the display 31 to display a Landolt ring target with a visual acuity value of 0.9, as in step S2 (step S5).

[0087] For example, the control unit 60 checks again whether the left eye can recognize the test target (step S6). For example, similar to step S3, the control unit 60 determines whether the left eye recognizes the test target based on the operation signal of the subject controller 20. For example, if the subject gives an incorrect answer (step S6: NO), the control unit 60 transitions to step S8 described below.

[0088] For example, when the subject answers correctly (step S6: YES), the control unit 60 checks whether the visual acuity value (0.9) of the current test optotype presented to the left eye reaches the upper limit (i.e., visual acuity value 1.0) of the measurement range in which the visual acuity value of the test optotype is changed (step S7). For example, the control unit 60 compares the visual acuity value of the current test optotype with the upper limit, and if the upper limit is reached (step S7: YES), the control unit 60 proceeds to step S8 described below.

[0089] For example, when the visual acuity value of the current test optotype presented to the left eye has not reached the upper limit of the measurement range for changing the visual acuity value of the test optotype (step S7: NO), the control unit 60 proceeds to step S4. For example, the control unit 60 repeats steps S4 to S7 in this manner to proceed with the subjective measurement until the visual acuity value of the current test optotype presented to the left eye reaches the upper limit of the measurement range or the subject gives an incorrect answer.

[0090] For example, the control unit 60 ends the subjective measurement when the subject gives an incorrect answer (step S6: NO) or when the visual acuity value of the test optotype presented to the left eye reaches the upper limit of the measurement range (step S7: YES). Also, for example, when the control unit 60 ends the subjective measurement for the left eye, it acquires the visual acuity value of the test optotype presented to the left eye as the second corrected visual acuity value (step S8). In other words, for example, the control unit 60 acquires the second corrected visual acuity value, which is the measurement result of the left eye in a state in which the ocular refractive power of the left eye is corrected by a contact lens with a predetermined correction power.

[0091] For example, the control unit 60 processes the program from step S1 to step S8 for the left eye, and when the second corrected visual acuity value of the left eye is obtained, the control unit 60 processes the program for the right eye in the same manner, and obtains the second corrected visual acuity value of the right eye. For example, the control unit 60 stores the second corrected visual acuity values ​​of the left eye and the right eye in the memory 70, respectively.

[0092] In the flowchart shown in FIG. 5, if the subject's eye is unable to recognize the visual acuity value (starting value) of the test target presented first and gives an incorrect answer (step S3: NO), the subjective measurement may be forcibly terminated.

[0093] <Determining whether or not the correction degree is appropriate> When the second corrected visual acuity value of the test eye is obtained, it is determined whether or not the correction power for correcting the ocular refractive power of the test eye is suitable. For example, since the test eye has been corrected with a previously prescribed contact lens, it is determined whether or not the correction power of the contact lens, which has a spherical power of -2.00D, a cylindrical power of 0.00D, and an astigmatism axis angle of 0 degrees, is suitable for the test eye.

[0094] For example, the control unit 60 judges whether the correction power of the eye to be examined is appropriate by judging whether the second corrected visual acuity value of the eye to be examined exceeds a reference value set based on the first corrected visual acuity value of the eye to be examined. For example, the control unit 60 compares the reference value with the second corrected visual acuity value, and if the reference value and the second corrected visual acuity value are the same value, judges that the correction power of the eye to be examined is appropriate. Also, for example, the control unit 60 compares the reference value with the second corrected visual acuity value, and if the second corrected visual acuity value is lower (smaller) than the reference value, judges that the correction power of the eye to be examined is inappropriate.

[0095] In this embodiment, if the visual acuity value 1.0 set as the reference value of the current subjective measurement of the eye to be examined and the second corrected visual acuity value of the eye to be examined are the same value, the control unit 60 determines that the corrected power of the eye to be examined is appropriate. Also, if the second corrected visual acuity value is lower than the visual acuity value 1.0 set as the reference value (i.e., the second corrected visual acuity value is less than 1.0), the control unit 60 determines that the corrected power of the eye to be examined is not appropriate. In this embodiment, the upper limit value of the measurement range for changing the visual acuity value of the test optotype for the eye to be examined and the reference value are the same value, and the subjective measurement ends when the second corrected visual acuity value reaches the upper limit value, so that the second corrected visual acuity value does not become a higher value (larger value) than the reference value.

[0096] <Execution of prescribed controls> When the appropriateness of the correction power of the eye to be examined is determined, a predetermined control is executed based on the determination result. Here, the predetermined control in response to the case where the correction power of the eye to be examined is determined to be appropriate and the case where the correction power of the eye to be examined is determined to be inappropriate will be described.

[0097] First, a case where the correction power of the test eye is determined to be appropriate will be described. For example, when the correction power of the test eye is determined to be appropriate, the examiner may be notified that the subjective measurement of the test eye has ended. For example, the control unit 60 may control the monitor 12 of the examiner controller 10 based on a determination signal indicating that the power of the test eye is appropriate, and may notify the end of the measurement by displaying the measurement result of the test eye. Also, for example, the control unit 60 may control the monitor 12 of the examiner controller 10 based on a determination signal indicating that the power of the test eye is appropriate, and may notify the end of the measurement by displaying guide information for the examiner. Also, for example, the control unit 60 may control a lamp (not shown) based on a determination signal indicating that the power of the test eye is appropriate, and may notify the end of the measurement by turning it on or blinking. Also, for example, the control unit 60 may control the speaker 3 based on a determination signal indicating that the power of the test eye is appropriate, and may notify the end of the measurement by generating a voice announcement. Note that the control unit 60 may execute at least any of these controls.

[0098] In this embodiment, an example will be given of a case where measurement results and guide information are displayed on the monitor 12. Fig. 6 is an example of an operation screen 200 displayed on the monitor 12. For example, the operation screen 200 is composed of an operation image area 210, a parameter screen 220, and the like.

[0099] In the operation image area 210, an operation image including information on the ocular refractive power when the examinee's eye is corrected by the ocular refractive power measuring unit 40 is displayed. For example, in the operation image, values ​​related to the optical characteristics of the examinee's eye are displayed for each type of optical characteristic. In this embodiment, since an opening is disposed in the test window 43, each value is displayed as 0.

[0100] Various parameters in the subjective measurement of the subject's eye are displayed on the parameter screen 220. For example, the parameter screen 220 displays a first corrected visual acuity value 221 of the subject's eye, a reference value 222 for the subjective measurement, an upper limit value 223 and a lower limit value 224 in the measurement range of the visual acuity value of the test optotype, a second corrected visual acuity value 225 of the subject's eye, a message display field 226, and the like.

[0101] For example, a message 227 for notifying the examiner that the subjective measurement of the subject's eye has been completed is displayed in the message display field 226. Also, for example, guide information 228 indicating the examiner's next action may be displayed in the message display field 226. As an example, such guide information may be an operation button or the like for guiding the examiner to end the subjective measurement.

[0102] For example, the control unit 60 displays the measurement result and the guide information 228 on the monitor 12 based on a determination signal indicating that the power of the test eye is appropriate. For example, the examiner can end the subjective examination of the test eye by checking the measurement result of the test eye and the guide information 228. In addition, for example, the examiner can determine whether there is a problem with the current correction power for correcting the ocular refractive power of the test eye. As an example, the examiner may compare the first corrected visual acuity value 221 and the second corrected visual acuity value 225 of the test eye, and when these values ​​are the same, determine that there is no problem with the current correction power of the test eye. For example, the examiner may prescribe contact lenses for the test eye when determining that there is no problem with the current correction power of the test eye. The examiner may re-prescribe contact lenses (spherical power -2.00D, cylindrical power 0.00D, astigmatism axis angle 0 degrees) with the same correction power as the contact lenses previously prescribed for the test eye. Of course, the examiner may perform additional measurements on the test eye as necessary.

[0103] Next, a case where the correction power of the subject's eye is determined to be inappropriate will be described. Fig. 7 is an example of an operation screen 200 displayed on the monitor 12. The configuration of the operation screen of Fig. 7 is the same as that of the operation screen 200 of Fig. 6, and therefore the description will be omitted. Here, a case where the second corrected visual acuity value of both the left and right eyes is 0.9 in the subjective measurement of the subject's eye is illustrated. For example, when there is a difference between the first corrected visual acuity value 221 and the second corrected visual acuity value 225, the second visual acuity correction value 225 may be highlighted (for example, bold, underlined, changed in text color, etc.).

[0104] For example, the control unit 60 displays the measurement result and the guide information on the monitor 12 based on a determination signal indicating that the power of the test eye is not appropriate. For example, as the guide information, a message for guiding the examiner to perform an additional measurement in the subjective measurement may be displayed. As an example, a message for guiding the examiner to perform a self-eye examination in which a plurality of test items are sequentially performed on the test eye may be displayed. For example, the examiner can determine whether or not there is a problem with the current correction power for correcting the eye refractive power of the test eye by checking the measurement result of the test eye and the guide information. As an example, the examiner may compare the first corrected visual acuity value 221 and the second corrected visual acuity value 225 of the test eye and determine that there is a problem with the current correction power of the test eye when these values ​​are not the same. Also, for example, when the examiner determines that there is a problem with the current correction power of the test eye, the examiner may perform a self-eye examination of the test eye according to the guide information to obtain a more detailed measurement result.

[0105] The examiner starts a more detailed subjective measurement of the subject's eye. For example, the examiner sets a second measurement mode to which a self-eye examination program for checking whether the correction power of the subject's eye is appropriate, and automatically proceeds with the subjective measurement.

[0106] For example, in a self-eye examination of the subject's eye, the correction power for correcting the eye refractive power of the subject's eye is changed by switching the optical element 52 arranged in the examination window 43, and measurements are performed in the order of red-green test (S), cross cylinder test (A), cross cylinder test (C), red-green test, and VA (visual acuity) test. In the red-green test (S), the spherical power of the subject's eye is measured. In the cross cylinder test (A), the astigmatism axis angle of the subject's eye is measured. In the cross cylinder test (C), the cylindrical power of the subject's eye is measured. In the subsequent red-green test, it is confirmed whether or not the subject's eye has adjusted in the previously performed test. In the VA (visual acuity) test, the maximum visual acuity of the subject's eye is measured (for details, refer to JP 2022-89255 A, etc.).

[0107] For example, the examiner may use the measurement results of the self-eye examination of the subject's eye to decide whether to re-prescribe contact lenses with the same corrective power as the contact lenses previously prescribed, or to prescribe new contact lenses with a different corrective power.

[0108] In the above, the self-eye examination is performed by determining whether the correction power of the eye to be examined is appropriate based on the measurement result of the first measurement mode for the eye to be examined, and then the examiner switches from the first measurement mode to the second measurement mode based on the appropriateness of the correction power (determination result), but this is not limiting. For example, the control unit 60 may automatically switch from the first measurement mode to the second measurement mode depending on the appropriateness of the correction power of the eye to be examined, thereby progressing the measurement according to the procedure of the self-eye examination program.

[0109] As described above, for example, the subjective ophthalmology device of this embodiment includes a first corrected visual acuity value acquisition means for acquiring a first corrected visual acuity value, which is a measurement result of measuring the highest visual acuity value of the subject's eye in a state where the ocular refractive power of the subject's eye is corrected with a predetermined corrective power; a reference value setting means for setting a reference value for confirming the suitability of the corrective power for the subject's eye based on the first corrected visual acuity value; a second visual acuity value acquisition means for acquiring a second corrected visual acuity value, which is a measurement result of measuring the subject's eye using a subjective measurement means in a state where the ocular refractive power of the subject's eye is corrected with a predetermined corrective power; and a control means for executing a predetermined control according to the suitability of the corrective power of the subject's eye based on whether the second corrected visual acuity value of the subject's eye exceeds the reference value. For example, if the subject wears glasses or contact lenses, a subjective measurement may be performed to confirm whether the current corrective power of the subject's eye needs to be changed. Usually, a subjective measurement involves performing a plurality of test items in sequence, which may result in a long measurement time overall and may be a burden on the examiner and the subject. However, for example, by providing the subjective optometry device with the configuration of this embodiment, the suitability of the current correction power of the subject's eye can be easily grasped, and control according to the suitability can be performed, so that the subjective measurement can be efficiently carried out. As an example, the subjective optometry device is used to screen the suitability of the current correction power of the subject's eye, and if there is no problem with the current correction power, the measurement is terminated as a control according to the suitability, thereby shortening the overall measurement time. In addition, for example, a reference value is set based on the first corrected visual acuity value, and the reference value is compared with the second corrected visual acuity value, so that the actual vision of the subject can be compared, and the suitability of the correction power of the subject's eye can be accurately determined.

[0110] Also, for example, in the subjective eye examination device of this embodiment, the reference value setting means sets a value equal to the first corrected visual acuity value or a value around the first corrected visual acuity value as a reference value for checking whether the corrective power of the eye to be examined is appropriate. For example, this makes it possible to easily determine whether the current corrective power is appropriate for the current eye to be examined even after a period of time has passed since glasses or contact lenses were prescribed for the eye to be examined. Also, depending on whether the current corrective power of the eye to be examined is appropriate, it is possible to easily grasp whether the ocular refractive power of the eye to be examined has changed. Note that, for example, when the same value as the first corrected visual acuity value is set as the reference value, it is even easier to determine whether the current corrective power is appropriate for the current eye to be examined.

[0111] Also, for example, the subjective optometry device of this embodiment includes a measurement range setting means for setting a measurement range in which the visual acuity value of the test optotype presented to the subject's eye is changed based on the first corrected visual acuity value when the subjective measurement means measures the subject's eye, and the subjective measurement means changes the visual acuity value of the test optotype based on the measurement range set by the measurement range setting means. For example, the measurement range of the visual acuity value of the test optotype presented by the subjective optometry device in the subjective measurement is a preset arbitrary measurement range that differs for each device. As an example, the visual acuity value of the test optotype is initially set to a range of 0.1 to 1.5. In this case, a test optotype with a visual acuity value of 0.1 is first presented to the subject's eye, and then the visual acuity value is changed in sequence, and when the visual acuity value reaches 1.5, the subjective measurement is terminated. In this case, the wider the measurement range of the visual acuity value of the test optotype presented to the subject's eye, the more time is required for the subjective measurement, and the more likely it is to be a burden. However, as in this embodiment, when the measurement range is set based on the first corrected visual acuity value of the subject's eye, the visual acuity value at which the subject's eye is considered to be able to recognize the test optotype without any problem can be omitted, and the subjective measurement can be carried out. In other words, the measurement range of the visual acuity value of the test optotype can be made narrower than usual, and the subjective measurement can be carried out. This can shorten the measurement time of the subject's eye.

[0112] Also, for example, in the subjective eye examination device of this embodiment, the measurement range setting means sets the highest upper limit value of the measurement range in which the visual acuity value of the test optotype is changed based on the first corrected visual acuity value of the subject's eye, and the subjective measurement means changes the visual acuity value of the test optotype in order from the lowest value based on the measurement range set by the measurement range setting means, and ends the measurement when the visual acuity value reaches the upper limit value. For example, this allows the highest visual acuity value among the visual acuity values ​​at which the subject's eye can recognize the test optotype without any problems to be set as the upper limit value of the measurement range. Therefore, the measurement range of the visual acuity value of the test optotype presented in the subjective measurement of the subject's eye is narrowed, and the measurement time can be shortened.

[0113] Also, for example, in the subjective eye examination device of this embodiment, the measurement range setting means sets the lowest lower limit value of the measurement range in which the visual acuity value of the test optotype is changed based on the first corrected visual acuity value of the subject's eye, and the subjective measurement means changes the visual acuity value of the test optotype from the lower limit value to the highest visual acuity value based on the measurement range set by the measurement range setting means. For example, this allows the lowest visual acuity value among the visual acuity values ​​at which the subject's eye can recognize the test optotype without any problems to be set as the lower limit value of the measurement range. Therefore, the measurement range of the visual acuity value of the test optotype presented in the subjective measurement of the subject's eye is narrowed, and the measurement time can be shortened. Note that when the upper and lower limits of the measurement range are set based on the first corrected visual acuity value of the subject's eye, an appropriate measurement range is set according to the recognition of the test optotype by the subject's eye, and the measurement time can be further shortened.

[0114] Also, for example, in the subjective optometry device of this embodiment, the control means executes a guidance process for guiding the next action corresponding to the correction power of the subject's eye as a predetermined control according to whether the correction power of the subject's eye is appropriate. As an example, at least one of the guidance processes may be executed, such as a guidance process for guiding the next action to be executed by the control unit of the subjective optometry device, a guidance process for guiding the next action to be executed by the examiner, etc. This allows an appropriate response to be taken according to the current correction power of the subject's eye.

[0115] In addition, for example, in the subjective optometry device of this embodiment, the control means outputs guide information indicating the examiner's next action as a guidance process for guiding the examiner to the next action corresponding to the correction power of the examinee's eye. For example, this allows the examiner to take an appropriate action according to the current correction power of the examinee's eye.

[0116] Also, for example, the subjective eye examination device of this embodiment has a first measurement mode that at least controls the optotype presenting means based on the answer input by the examinee to automatically proceed with an eye examination program for checking whether the correction power of the eye to be examined is appropriate, and a second measurement mode that controls at least one of the optotype presenting means and the correction means based on the answer input by the examinee to automatically proceed with a self-eye examination program including a plurality of examination items for the eye to be examined, and the control means executes a switch from the first measurement mode to the second measurement mode as a predetermined control according to whether the correction power by executing the first measurement mode is appropriate, and proceeds with the measurement according to the procedure of the self-eye examination program. As a result, for example, if the current correction power of the eye to be examined is not appropriate, the device transitions to a self-eye examination, and a more detailed eye examination is performed, including changing the correction power of the eye to be examined and obtaining a corrected visual acuity value associated with the change in the correction power of the eye to be examined. Therefore, for example, the examiner can easily determine the next correction power of the eye to be examined by using the result of the self-eye examination of the eye to be examined.

[0117] <Example of transformation> In the subjective eye examination device of this embodiment, the subjective measurement is performed in a state where the subject's eye is corrected by wearing the contact lens prescribed last time and the eye refraction measurement unit 40 is placed in front of the eye, but the present invention is not limited to this. In this embodiment, it is sufficient to perform the subjective measurement in a state where the eye refraction of the subject's eye E is corrected with the same correction power as the last prescription. For example, the subjective measurement may be performed in a state where the subject's eye wears a contact lens (or glasses) and the eye refraction measurement unit 40 is retracted. In this case, when moving to self-eye examination of the subject's eye, the eye refraction measurement unit 40 may be lowered to the measurement position. Also, for example, the subjective measurement may be performed by placing the eye refraction measurement unit 40 in front of the naked eye and adding the same correction power as when the contact lens (or glasses) is worn.

[0118] In the subjective eye examination device of this embodiment, the case where only the far-use test of the eye to be examined is performed has been described as an example, but the present invention is not limited thereto. In this embodiment, only the near-use test of the eye to be examined may be performed. In addition, in this embodiment, both the far-use test and the near-use test of the eye to be examined may be performed. For example, when both the far-use test and the near-use test of the eye to be examined are performed, a far-use target may be presented to the eye to be examined at a far-use distance and a near-use target may be presented at a near-use distance, and the second corrected visual acuity value at each distance may be obtained, thereby checking whether there is a problem even if the progressive contact lens of the eye to be examined has the same power.

[0119] For example, a case will be taken in which the subject's eye is wearing a progressive contact lens prescribed previously and an opening is arranged in the test window 43 of the eye refractive power measuring unit 40. First, a distance test is performed on the subject's eye with the display 31 placed for distance. For example, the control unit 60 may obtain a first corrected visual acuity value in the previous distance test determined when the subject's eye was prescribed a progressive contact lens for the previous distance test. Also, for example, the control unit 60 may set a reference value for the current distance test and a measurement range (upper and lower limits) of the visual acuity value of the test optotype presented in the current distance test based on the first corrected visual acuity value. Furthermore, for example, the control unit 60 may perform a distance test on the subject's eye and obtain a second corrected visual acuity value for the distance test on the subject's eye. Next, a near test is performed with the display 31 placed for near. For example, the control unit 60 may similarly obtain a first corrected visual acuity value in the previous near test and set an upper and lower limit of the visual acuity value of the test optotype based on the first corrected visual acuity value. Also, for example, the control unit 60 may perform a distance test on the subject's eye and obtain a second corrected visual acuity value in a near test on the subject's eye.

[0120] For example, the examiner may determine whether or not there is a problem with the current correction power for correcting the ocular refractive power of the subject's eye based on the comparison result of the first corrected visual acuity value and the second corrected visual acuity value in the distance test of the subject's eye, and the comparison result of the first corrected visual acuity value and the second corrected visual acuity value in the near test of the subject's eye. As an example, the examiner may determine that there is no problem with the current correction power of the subject's eye when the comparison result of the distance test of the subject's eye and the comparison result of the near test of the subject's eye are both the same value. Also, as an example, the examiner may determine that there is a problem with the current correction power of the subject's eye when at least one of the comparison results of the distance test of the subject's eye and the comparison result of the near test of the subject's eye are different values.

[0121] In the subjective eye examination device of this embodiment, a configuration in which a self-eye examination is performed on the subject's eye when the second corrected visual acuity value of the subject's eye does not meet the reference value has been described as a predetermined control according to the suitability of the corrective power of the subject's eye, but the present invention is not limited to this. For example, as a predetermined control according to the suitability of the corrective power of the subject's eye, when the second corrected visual acuity value of the subject's eye does not meet the reference value, an additional spherical power may be added to the subject's eye.

[0122] For example, when the control unit 60 determines that the second corrected visual acuity value of the subject's eye does not meet the reference value and the current corrective power of the subject's eye is not appropriate, it adds one step of stronger spherical power to the subject's eye. As an example, if the subject's eye is myopic, a -0.25D spherical lens is placed in the test window 43, and if the subject's eye is hyperopic, a +0.25D spherical lens is placed in the test window 43. As a result, the subject's eye is corrected with one step stronger corrective power than the state where it is corrected with the current corrective power.

[0123] For example, the control unit 60 presents a test optotype corresponding to the visual acuity value when the corrective power of the subject's eye is determined to be inappropriate, with additional spherical power added to the subject's eye. For example, if the subject recognizes the test optotype and answers correctly, the control unit 60 changes the visual acuity value of the test optotype to a visual acuity value one level higher. For example, the control unit 60 repeats the program until the subject answers incorrectly or the visual acuity value of the test optotype reaches the upper limit of the measurement range, thereby obtaining the second corrected visual acuity value of the subject's eye again.

[0124] For example, the examiner can determine whether there is a problem with the corrective power of the test eye after the additional spherical power is added by comparing the first corrected visual acuity value of the test eye with the reacquired second corrected visual acuity value. As an example, if there is no problem with the corrective power of the test eye after the additional spherical power is added, a contact lens having a corrective power obtained by adding an additional spherical power to the corrective power of the contact lens previously prescribed may be prescribed. Also, as an example, if there is a problem with the corrective power of the test eye after the additional spherical power is added, a self-eye examination of the test eye may be performed subsequently.

[0125] For example, in this embodiment of the subjective eye examination device, the subjective measuring means has a correcting means for changing the optical characteristics of the target light beam emitted from the target presenting means, and the control means, when the eye refractive power of the test eye is corrected with a predetermined correction power and the second corrected visual acuity value of the test eye does not meet the reference value, controls the correcting means to add a spherical power to the predetermined correction power, and the second corrected visual acuity value acquiring means acquires the second corrected visual acuity value again with a correction power different from the predetermined correction power. For example, when the current correction power determined based on the first corrected visual acuity value of the test eye is no longer suitable (i.e., when the visual acuity of the test eye has deteriorated), the second corrected visual acuity value of the test eye may not meet the reference value. Therefore, by obtaining the second corrected visual acuity value obtained by adding a spherical power to the current corrected visual acuity of the test eye, it is possible to easily grasp an appropriate correction power that takes into account the deterioration of the visual acuity of the test eye.

[0126] In the subjective eye examination device of this embodiment, a configuration has been described in which, as a predetermined control according to the suitability of the correction power of the eye to be examined, when the second corrected visual acuity value of the eye to be examined is the same as the reference value, the subjective measurement of the eye to be examined is terminated, but this is not limited thereto. For example, as a predetermined control according to the suitability of the correction power of the eye to be examined, when the second corrected visual acuity value of the eye to be examined is the same as the reference value, an additional spherical power may be added to the eye to be examined.

[0127] For example, when the control unit 60 determines that the second corrected visual acuity value of the subject's eye is equal to the reference value and that the current corrective power of the subject's eye is appropriate, it adds a one-step weaker spherical power to the subject's eye. As an example, if the subject's eye is myopic, a +0.25D spherical lens is placed in the test window 43, and if the subject's eye is hyperopic, a -0.25D spherical lens is placed in the test window 43. As a result, the subject's eye is corrected with a correction power one step weaker than the state where it is corrected with the current correction power.

[0128] For example, the control unit 60 presents a test optotype corresponding to the visual acuity value when the corrective power of the subject's eye is determined to be appropriate with additional spherical power added to the subject's eye. For example, the control unit 60 ends the subjective measurement regardless of whether the subject recognizes the test optotype and answers correctly or incorrectly, and again obtains the second corrected visual acuity value of the subject's eye.

[0129] For example, the examiner can check whether the test eye was overcorrected at the time of the previous subjective measurement by comparing the first corrected visual acuity value of the test eye with the reacquired second corrected visual acuity value. For example, the overcorrected state is a state in which a light beam incident on the test eye forms an image behind the retina when the test eye is in a resting accommodation state due to the addition of a correction power different from the correction power required for optimal correction of the test eye.

[0130] For example, if the examinee answers incorrectly and obtains a final second corrected visual acuity value that is the same as the first corrected visual acuity value, the examiner may determine that the examinee's eye was not overcorrected at the time of the previous subjective measurement. In this case, the examiner may prescribe a contact lens with the same corrective power as the contact lens previously prescribed. Also, for example, if the examinee answers correctly and obtains a final second corrected visual acuity value that is one level weaker than the first corrected visual acuity value, the examiner may determine that the examinee's eye may have been overcorrected at the time of the previous subjective measurement. In this case, the examiner may prescribe a contact lens with a corrective power that is an additional spherical power to the corrective power of the contact lens previously prescribed.

[0131] For example, in this embodiment of the subjective eye examination device, the subjective measuring means has a correcting means for changing the optical characteristics of the target light beam emitted from the target presenting means, and the control means, when the eye refractive power of the test eye is corrected with a predetermined correction power and the second corrected visual acuity value of the test eye is the same as the reference value, controls the correcting means to add a spherical power to the predetermined correction power, and the second corrected visual acuity value acquiring means acquires the second corrected visual acuity value again with a correction power different from the predetermined correction power. For example, this makes it possible to confirm the possibility that the test eye was in an overcorrected state when the first corrected visual acuity value of the test eye was measured. For example, it is possible to easily determine whether the test eye was in an overcorrected state without performing a series of examination items in a normal subjective measurement. [Explanation of symbols]

[0132] 1 Case 2 Presentation window 3 Speakers 10 Examiner's controller 30 Projection optical system 40 Eye Refractive Index Measuring Unit 43 Inspection window 60 Control section 100 Self-examination device

Claims

1. A subjective optometry device for subjectively measuring the optical properties of an eye, comprising a subjective measuring means for measuring at least the visual acuity of an eye by projecting a target light beam from a target presentation means toward the eye to be examined and presenting the examination target to the eye, A first corrected visual acuity acquisition means for acquiring a first corrected visual acuity value, which is the measurement result of measuring the highest visual acuity of the eye under examination while the refractive power of the eye under examination is corrected with a predetermined corrective power, A reference value setting means for setting a reference value for confirming the appropriateness of the corrected power for the eye under examination, based on the first corrected visual acuity value, A second corrected visual acuity acquisition means for acquiring a second corrected visual acuity value, which is the measurement result of measuring the eye under examination using the subjective measurement means while the refractive power of the eye under examination is corrected with the predetermined corrective power, A control means that performs a predetermined control according to the appropriateness of the corrected power of the eye under examination, based on whether the second corrected visual acuity of the eye under examination exceeds the reference value, A subjective optometry device characterized by being equipped with the following features.

2. In the subjective ophthalmoscopic device of claim 1, The reference value setting means is characterized in that it sets the reference value to be the same as the first corrected visual acuity value, or a value around the first corrected visual acuity value, for confirming the appropriateness of the corrected power of the eye to be examined.

3. In the subjective ophthalmoscopic device of claim 1 or 2, When measuring the eye under test using the subjective measurement means, the measurement range setting means sets the measurement range in which the visual acuity value of the test target presented to the eye under test is changed, based on the first corrected visual acuity value. The subjective measurement means is characterized by changing the visual acuity value of the test target based on the measurement range set by the measurement range setting means.

4. In the subjective eye examination device of Claim 1, The control means is characterized in that, as a predetermined control according to whether the corrected power of the eye to be examined is appropriate, it performs a guidance process to induce the next action corresponding to the corrected power of the eye to be examined.

5. In the subjective eye examination device of Claim 1, The subjective measurement means includes a correction means for changing the optical properties of the target light beam emitted from the target presentation means. The control means controls the correction means to add a spherical power to the predetermined correction power when the second corrected visual acuity of the eye under examination falls below the reference value, while the refractive power of the eye under examination has been corrected by the predetermined correction power. The subjective optometry device is characterized in that the second corrected visual acuity value acquisition means acquires the second corrected visual acuity value again with a corrected power different from the predetermined corrected power.

6. In the subjective eye examination device of Claim 1, A first measurement mode that controls the target presentation means based on the answers entered by the subject and automatically proceeds with an eye examination program to confirm the appropriateness of the corrective power of the subject's eye, A second measurement mode controls at least one of the visual target presentation means and the correction means based on the answers entered by the subject, and automatically proceeds with a self-examination program that includes multiple examination items for the subject's eye. It has, The control means is characterized in that, depending on whether the corrected power is appropriate or not based on the execution of the first measurement mode, it performs a predetermined control by switching from the first measurement mode to the second measurement mode, and proceeds with the measurement in accordance with the procedure of the self-examination program.

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