Subjective eye examination device

Abstract

To provide a subjective optometer capable of accurately measuring optical characteristics of an eye to be examined.SOLUTION: A subjective optometer includes a light projection optical system for projecting a target light flux toward an eye to be examined, a correction optical system for changing optical characteristics of the target light flux, and a fixed optical member disposed fixed in an optical path of the light projection optical system for optically presenting an image of the target light flux to the eye to be examined with a predetermined examination distance. The subjective optometer incudes first moving means for positioning an optical axis of the light projection optical system for the eye to be examined by moving a measuring unit at least including the light projection optical system with respect to the fixed optical member, second moving means for executing positioning for projecting the image of the target light flux onto the eye to be examined with a predetermined optical magnification ratio by moving the measuring unit and the fixed optical member with respect to the eye to be examined in a state of maintaining the mutual positional relationships, and moving control means for controlling the first moving means and the second moving means in the positioning between the eye to be examined and the measuring unit.SELECTED DRAWING: Figure 1

Description

[Technical Field]

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

[0002] There is known a subjective optometry device that subjectively measures the optical characteristics of a subject's eye. For example, in Patent Document 1, a target light beam from a measurement unit is guided to the subject's eye via a fixed optical member (concave mirror) that is fixedly disposed. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2017-86652 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the above configuration, the measurement unit moves relative to the fixed optical member, which is fixedly disposed, and therefore it is possible that the optical characteristics of the subject's eye cannot be measured accurately. For example, if the measurement unit moves significantly, the relationship between the distance from the subject's eye to the fixed optical member and the distance from the measurement unit to the fixed optical member changes, and the optical magnification is likely to change. Furthermore, for example, if the measurement unit moves significantly, optical aberrations are likely to occur.

[0005] In view of the above-described conventional techniques, the present disclosure has as its technical object to provide a subjective optometry device that can accurately measure the optical characteristics of a subject's eye. [Means for solving the problem]

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

[0007] A subjective ophthalmology device according to a first aspect of the present disclosure has a projection optical system that projects a visual target light beam toward an eye to be examined, a corrective optical system that changes the optical characteristics of the visual target light beam, and a fixed optical element that is fixedly arranged in the optical path of the projection optical system and that optically presents an image of the visual target light beam to the eye to be examined at a predetermined examination distance, and is a subjective ophthalmology device for subjectively measuring the optical characteristics of the eye to be examined, characterized in that it comprises: a first moving means for aligning the optical axis of the projection optical system with the eye to be examined by moving a measurement unit including at least the projection optical system relative to the fixed optical element; a second moving means for aligning the measurement unit and the fixed optical element with the eye to be examined so that the image of the visual target light beam is projected on the eye to be examined at a predetermined optical magnification by moving the measurement unit and the fixed optical element relative to the eye to be examined while maintaining the positional relationship between the measurement unit and the fixed optical element; and a movement control means for controlling the first moving means and the second moving means in aligning the eye to be examined and the measurement unit. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is an external view of a subjective optometry device. [Figure 2] FIG. 10 is a diagram showing a measurement unit for the left eye. [Figure 3] FIG. 2 is a schematic view of the inside of the device as seen from the front. [Figure 4] FIG. 2 is a schematic side view of the inside of the device. [Figure 5] FIG. 2 is a schematic diagram showing the inside of the device as viewed from above. [Figure 6] FIG. 1 is a simplified diagram in which optical members inside the device are arranged in a straight line. [Figure 7] FIG. [Figure 8] FIG. 3 is a diagram showing the positions of a first unit and a second unit relative to the subject's eye. [Figure 9] FIG. 10 is a diagram showing the position of the first unit relative to the concave mirror. DETAILED DESCRIPTION OF THE INVENTION

[0009] <Summary> An overview of a subjective optometry device according to an embodiment of the present disclosure will be described. In this embodiment, the left-right direction of the subjective optometry device is defined as the X direction, the up-down direction as the Y direction, and the front-back direction (working distance direction) as the Z direction. The symbols L and R indicate left and right eye use, respectively. Note that the items classified in < > below can be used independently or in association with each other.

[0010] The subjective optometry device of this embodiment subjectively measures the optical characteristics of the subject's eye. For example, it may measure at least one of ocular refractive power (spherical power, cylindrical power, astigmatic axis angle, etc.), contrast sensitivity, binocular vision function (amount of heterophoria, stereoscopic vision function, etc.). The subjective optometry device includes a measuring means (for example, a measuring unit 7). For example, the measuring means may include a subjective measuring means. Also, for example, the measuring means may include an objective measuring means. Note that in this embodiment, it is sufficient that the measuring means includes at least a subjective measuring means, and it may include both a subjective measuring means and an objective measuring means.

[0011] <Subjective measurement method> The subjective optometry device includes a subjective measurement means (e.g., a subjective measurement optical system 25). For example, the subjective measurement means includes at least a light projection optical system (e.g., a light projection optical system 30) that projects a visual target light beam toward the subject's eye. Furthermore, the subjective measurement means may include a correction optical system (e.g., a correction optical system 60) that changes the optical properties of the visual target light beam.

[0012] <Projection optical system> 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.

[0013] The light projection optical system may include a target presenting means. The target presenting means presents a target to the eye to be examined. In this case, the light projection optical system projects a target light beam emitted from the target presenting means toward the eye to be examined. For example, the target presenting means may be a display (e.g., display 31). For example, the target presenting means may be a light source and a DMD (Digital Micromirror Device). Generally, a DMD has high reflectivity and is bright, so it can maintain the light intensity of the target light beam more than an LCD. For example, the target presenting means may be a visible light source for presenting the target and a target plate. The target plate may be a rotatable disk plate and may have multiple targets. The target plate is rotated by a motor or the like on the optical path along which the target light beam is guided to the eye to be examined, thereby switching and positioning the target.

[0014] The light-projecting optical system may include a pair of left-eye and right-eye light-projecting optical systems. For example, the components constituting the left-eye and right-eye light-projecting optical systems may be the same, or at least some of the components may be different. Furthermore, for example, the left-eye and right-eye light-projecting optical systems may be configured such that at least some of the components constituting the left-eye and right-eye light-projecting optical systems are shared between the components constituting the left-eye and right-eye light-projecting optical systems.

[0015] <Correction optical system> The correction optical system is disposed in the optical path of the projection optical system, and changes the optical characteristics (at least one of spherical power, cylindrical power, astigmatic axis angle, polarization characteristics, amount of aberration, etc.) of the visual target light beam.

[0016] For example, the corrective optical system may be capable of changing at least one of the spherical power, cylindrical power, and astigmatic axis angle of the visual target light beam by controlling the optical element. 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, an optical element other than these optical elements may also be used.

[0017] Furthermore, for example, the corrective optical system may correct the spherical power of the subject's eye by optically changing the presentation distance of the optotype relative to the subject's eye. In this case, the optotype presentation means may be configured to move in the optical axis direction in order to optically change the presentation distance of the optotype. In this case, the optical element (e.g., a spherical lens) arranged in the optical path may be configured to move in the optical axis direction in order to optically change the presentation distance of the optotype.

[0018] In addition, the corrective optical system may be configured by combining a configuration for controlling an optical element, a configuration for moving a target presenting means in the optical axis direction, and a configuration for moving an optical element arranged in the optical path in the optical axis direction.

[0019] In this embodiment, the corrective optical system may be an eye refraction measurement unit (phoropter) that places an optical element in front of the eye to be examined. For example, the eye refraction measurement unit may have a variable-focus lens and be configured to change the refractive power of the variable-focus lens. Furthermore, for example, the eye refraction measurement unit may have a lens disk on which multiple 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 measurement unit may also have a variable-focus lens, a lens disk, and a driving means. In such a configuration, a target light beam directed toward the eye to be examined is projected via the eye refraction measurement unit.

[0020] In addition, in this embodiment, the correction optical system may be configured such that an optical element is disposed between the optotype presenting means and an optical member for guiding the optotype light beam from the light projecting optical system toward the subject's eye, and the optical characteristics of the optotype light beam are changed by controlling the optical element. That is, the correction optical system may be configured as a phantom lens refractometer (phantom correction optical system). In this case, the optotype light beam corrected by the correction optical system is guided to the subject's eye via the optical member.

[0021] The corrective optical system may include a pair of corrective optical systems for the left and right eyes. For example, the components constituting the corrective optical system for the left eye and the components constituting the corrective optical system for the right eye may be the same, or at least some of the components may be different. Furthermore, for example, the corrective optical system for the left eye and the corrective optical system for the right eye may be configured such that at least some of the components constituting the corrective optical system for the left eye and the components constituting the corrective optical system for the right eye are shared.

[0022] <Objective measurement means> The subjective ophthalmological examination apparatus may include an objective measuring means (e.g., an objective measuring optical system 10) that objectively measures optical characteristics of the subject's eye. For example, the objective measuring means may include a projection optical system (e.g., a projection optical system 10a) that projects a measurement light beam onto the fundus of the subject's eye, and a light receiving optical system (e.g., a light receiving optical system 10b) that receives a light beam reflected from the fundus. Note that the objective optical characteristics that may be measured include at least one of ocular refractive power (e.g., spherical power, cylindrical power, astigmatic axis angle, etc.), axial length, corneal shape, etc.

[0023] <Fixed optical components> The subjective ophthalmology device includes a fixed optical member. The fixed optical member is fixedly disposed in the optical path of the light projection optical system and is a fixed optical member for optically presenting an image of a visual target light beam to the subject's eye at a predetermined examination distance. For example, the fixed optical member may guide the visual target light beam from the light projection optical system to the subject's eye. Also, for example, the fixed optical member may guide the visual target light beam projected from the light projection optical system and further corrected by the correction optical system to the subject's eye. Note that the fixed optical member may be shared by both the optical path of the visual target light beam from the left eye measurement unit (described later) and the optical path of the visual target light beam from the right eye measurement unit (described later). For example, the fixed optical member may be at least one of a concave mirror (e.g., concave mirror 85), a lens, etc.

[0024] In this embodiment, a concave mirror is used to optically present an image of the target light beam to the subject's eye at a predetermined test distance, which eliminates the need to place a predetermined optical member at the actual distance, thereby enabling the device to be more space-saving.

[0025] <1st means of transportation> The subjective optometry device includes a first moving means (e.g., a first moving unit 9). The first moving means aligns the optical axis of the projection optical system with the subject's eye by moving a measurement unit (e.g., a first unit A1) relative to a fixed optical member. In this embodiment, the first moving means may be configured to move at least the measurement unit in the X and Y directions. For example, the subject's eye tends to move in the X and Y directions, which may cause a misalignment between the subject's eye and the optical axis, resulting in an inability to properly present the target. However, this configuration reduces this possibility. Note that movement of the subject's eye in the Z direction can be addressed by using a second moving means (described later), but the first moving means may also be configured to move the measurement unit in the Z direction. In other words, the first moving means may move the measurement unit in three dimensions relative to the fixed optical member. This allows the optical axis of the projection optical system to be positioned more appropriately in accordance with the movement of the subject's eye.

[0026] For example, the measurement unit may be a unit including at least a light-projecting optical system. As an example, the measurement unit may be configured as a measurement unit including a light-projecting optical system, or as a measurement unit including a light-projecting optical system and a corrective optical system. Of course, the measurement unit may be configured as a measurement unit including other optical components in addition to the light-projecting optical system. Note that the measurement unit may have a pair of left and right measurement units, one for the left eye including a light-projecting optical system for the left eye (and a corrective optical system for the left eye) and the other for the right eye including a light-projecting optical system for the right eye (and a corrective optical system for the right eye).

[0027] In this embodiment, a first moving means may be used to detect the line of sight of the subject's eye and align the line of sight (in other words, the visual axis) with the optical axis of the light projection optical system. The line of sight of the subject's eye may be the position of the line of sight at which the subject's eye gazes at the image of the visual target light beam. For example, it may be the position of the line of sight based on the interpupillary distance of the subject's eye, or the position of the line of sight based on the convergence angle corresponding to the optical presentation distance of the visual target relative to the subject's eye. Of course, it may also be the position of the line of sight based on both the interpupillary distance and the convergence angle of the subject's eye.

[0028] <Second transportation means> The subjective optometry device includes a second moving means (e.g., a second moving unit 8). The second moving means moves the measurement unit and the fixed optical member relative to the eye to be examined while maintaining the positional relationship between the measurement unit and the fixed optical member, thereby aligning the image of the visual target light beam to be projected onto the eye to be examined at a predetermined optical magnification. In other words, the measurement unit and the fixed optical member are moved integrally relative to the eye to align the image of the visual target light beam to be projected onto the eye to be examined at a predetermined optical magnification. This maintains the optical magnification of the image of the visual target light beam projected onto the eye to be examined. In this embodiment, the second moving means is only required to be configured to move at least the measurement unit and the fixed optical member integrally in the Z direction. For example, when the eye to be examined moves in the Z direction, the optical magnification is likely to change, which may result in the visual target not being presented properly, but this configuration reduces this.

[0029] Of course, the second moving means may be configured to be able to move the measurement unit and the fixed optical member in the X and Y directions. That is, the second moving means may move the measurement unit and the fixed optical member integrally in three-dimensional directions relative to the eye to be examined. Furthermore, in this embodiment, the second moving means may move the left eye measurement unit, the right eye measurement unit, and the fixed optical member integrally relative to the eye to be examined.

[0030] <Movement control means> The subjective ophthalmology device includes a movement control means (e.g., a control unit 70). The movement control means controls the first movement means and the second movement means in aligning the eye to be examined with the measurement unit. For example, the movement control means may control the first movement means and the second movement means at the same timing. Alternatively, for example, the movement control means may control the first movement means and the second movement means at different timings. In this case, either the control of the first movement means or the control of the second movement means may be executed first. This allows the optical axes of the eye to be aligned with those of the projection optical system, and allows an image of the target light beam to be projected onto the eye to be examined at a predetermined optical magnification.

[0031] In this embodiment, the movement control means may perform alignment under the control of the first movement means after performing alignment under the control of the second movement means. In this case, first, the measurement unit and the fixed optical member are moved together while maintaining their positional relationship with respect to the test eye, and the optical magnification is adjusted, thereby allowing an appropriate image of the target light beam to be projected onto the test eye. Next, the measurement unit is moved relative to the test eye (relative to the fixed optical member) to align the optical axis of the projection optical system with the test eye, allowing an appropriate image of the target light beam to be projected onto the test eye. Note that by first performing alignment under the control of the second movement means, the movement of the measurement unit under the control of the first movement means is minimized, thereby further reducing potential optical aberrations.

[0032] In addition, in this embodiment, the movement control means may control the second movement means to perform coarse alignment of the measurement unit with respect to the eye to be examined, and may control the first movement means to perform fine alignment of the measurement unit with respect to the eye to be examined, thereby adjusting the alignment between the eye to be examined and the measurement unit. That is, the second movement means may be controlled to perform coarse alignment of the measurement unit with respect to the eye to be examined, and the first movement means may be controlled to perform fine alignment of the measurement unit with respect to the eye to be examined. For example, by coarsely aligning the optical magnification and then finely aligning the optical axes of the eye to be examined and the projection optical system, it is possible to minimize the occurrence of optical aberrations and present an appropriate optotype to the eye to be examined.

[0033] The movement control means may perform alignment (coarse alignment and fine alignment) between the eye to be examined and the measurement unit, and then control the first movement means to perform tracking to track the eye to be examined. For example, the measurement unit may be moved in response to the movement of the eye to be examined during subjective measurement (for example, fixational micromovement, etc.). By quickly responding to the movement of the eye to be examined and appropriately aligning the optical axes of the eye to be examined and the light projection optical system, an appropriate optotype can be presented to the eye to be examined.

[0034] Furthermore, in this embodiment, the movement control means may control the second movement means to move the measurement unit and the fixed optical member at least in the Z direction relative to the eye to be examined, and may also control the first movement means to move the measurement unit at least in the X and Y directions relative to the fixed optical member. This makes it possible to maintain a predetermined optical magnification in response to a deviation of the eye to be examined in the Z direction. Furthermore, it is possible to appropriately present an optotype to the eye to be examined in response to a deviation of the eye to be examined in the X and Y directions (i.e., a deviation of the optical axis relative to the eye to be examined).

[0035] <Location information acquisition means> The subjective ophthalmology device includes a position information acquiring means (e.g., a control unit 70). The position information acquiring means acquires position information of the measurement unit. For example, the position information of the measurement unit may be expressed as position coordinates of the measurement unit. Furthermore, for example, the position information of the measurement unit may be expressed as the three-dimensional distance from the subject's eye to the measurement unit, the three-dimensional distance from a fixed optical member to the measurement unit, etc.

[0036] In this embodiment, the measurement unit moves integrally with the fixed optical member as a moving unit (e.g., second unit A2). For example, the measurement unit is provided inside the moving unit and moves within the moving unit under the control of the first moving means. Therefore, the position information acquiring means may acquire position information of the measurement unit relative to the position information of the moving unit. More specifically, the position coordinates of the measurement unit relative to the moving unit may be obtained, or the distance in three-dimensional directions relative to the moving unit may be obtained.

[0037] <Correction means> The subjective ophthalmology device includes a correction unit (e.g., a control unit 70). The correction unit corrects optical aberrations that occur when the target light beam passes through a fixed optical member, based on position information of the measurement unit. For example, the correction unit may correct the optical aberrations by executing arithmetic processing based on the optical characteristics of the subject's eye and the position information of the measurement unit. Alternatively, for example, the correction unit may correct the optical aberrations by referring to a correction table based on the optical characteristics of the subject's eye and the position information of the measurement unit. The correction table may be stored in advance in a storage unit (e.g., a memory 75). This allows the subject's eye and the optical axis of the projection optical system to be properly aligned, even if, for example, the relationship between the optical magnifications is disrupted and optical aberrations occur.

[0038] For example, the correction means may include a correction amount setting means. The correction amount setting means may set a correction amount for correcting optical aberrations that occur when the visual target light beam passes through a fixed optical member. In this case, as an example, the correction means may correct the optical aberrations by controlling at least one of the light projection optical system and the correction optical system to change the optical characteristics of the visual target light beam based on the correction amount. Note that such correction amount may be determined by calculation processing or a correction table based on the optical characteristics of the subject's eye and positional information of the measurement unit. This makes it possible to accurately obtain the optical characteristics of the subject's eye.

[0039] <Example> An example of a subjective optometry apparatus (hereinafter referred to as optometry apparatus) according to this embodiment will be described.

[0040] FIG. 1 is an external view of an optometry apparatus 100. For example, the optometry apparatus 100 includes a housing 2, a presentation window 3, a forehead rest 4, a chin rest 5, a controller 6, an imaging unit 90, and the like. The housing 2 includes a measurement unit 7, a deflection mirror 81, a reflecting mirror 84, a concave mirror 85, and the like. The presentation window 3 is used to present a visual target to the subject's eye E. The forehead rest 4 and the chin rest 5 are used to maintain a constant distance between the subject's eye E and the optometry apparatus 1. The controller 6 includes a monitor 6a, a switch unit 6b, and the like. The monitor 6a displays various information (e.g., measurement results of the subject's eye, etc.). The monitor 6a may be a touch panel that also functions as the switch unit 6b. The switch unit 6b is used to perform various settings (e.g., input of a start signal, etc.). A signal corresponding to an operation instruction from the controller 6 is output to the control unit 70 via wired or wireless communication.

[0041] The imaging unit 90 is used to capture an image of the subject's face and adjust the position of the subject's eye in the Y direction. The imaging unit 90 includes an imaging optical system (not shown). For example, the imaging optical system may be composed of an imaging element and a lens. In this embodiment, the imaging unit 90 is provided in the second unit A2 (described later) and moves in the Z direction together with the second unit A2.

[0042] <Measurement part> The measurement unit 7 includes a left eye measurement unit 7L and a right eye measurement unit 7R. The left eye measurement unit 7L and the right eye measurement unit 7R are configured from the same components. Of course, the left eye measurement unit 7L and the right eye measurement unit 7R may be configured from at least a portion of different components. The measurement unit 7 includes a pair of left and right subjective measurement units and a pair of left and right objective measurement units (details will be described later). A target light beam and a measurement light beam from the measurement unit 7 are guided to the subject's eye E through the presentation window 3.

[0043] 2 is a diagram showing the left eye measurement unit 7L. The right eye measurement unit 7R has the same configuration as the left eye measurement unit 7L, so it is omitted. For example, the left eye measurement unit 7L includes an objective measurement optical system 10, a subjective measurement optical system 25, a first target projection optical system 45, a second target projection optical system 46, an observation optical system 50, etc.

[0044] <Objective measurement optical system> The objective measuring optical system 10 is used as part of an objective measuring unit that objectively measures the optical characteristics of the subject's eye E. In this embodiment, the ocular refractive power of the subject's eye E is measured as the optical characteristic of the subject's eye E. For example, the objective measuring optical system 10 is composed of a projection optical system 10a and a light-receiving optical system 10b.

[0045] The projection optical system 10a projects a spot-shaped measurement target onto the fundus of the subject's eye E through the center of the pupil of the subject's eye E. For example, the projection optical system 10a includes a light source 11, a relay lens 12, a hole mirror 13, a prism 15, an objective lens 93, a dichroic mirror 35, a dichroic mirror 29, and the like. The light source 11 emits a measurement beam. The light source 11 is conjugate with the fundus of the subject's eye E. The hole portion of the hole mirror 13 is conjugate with the pupil of the subject's eye E. The prism 15 is a beam deflecting member. The prism 15 is positioned away from a position conjugate with the pupil of the subject's eye E, and decenters the measurement beam passing through the prism 15 with respect to the optical axis L1. The prism 15 is driven to rotate around the optical axis L1 by a drive unit (motor) 23. The dichroic mirror 35 makes the optical path of the objective measurement optical system 10 and the optical path of the subjective measurement optical system 25 a common optical path. In other words, the optical axis L1 of the objective measurement optical system 10 and the optical axis L2 of the subjective measurement optical system 25 are coaxial. The dichroic mirror 29 is an optical path branching member. The dichroic mirror 29 reflects the measurement light beam from the projection optical system 10a and the target light beam from the projection optical system 30 (described later) and guides them to the subject's eye E.

[0046] The light-receiving optical system 10b extracts a ring-shaped fundus-reflected light beam reflected by the fundus of the subject's eye E through the pupil periphery of the subject's eye E. For example, the light-receiving optical system 10b includes a dichroic mirror 29, a dichroic mirror 35, an objective lens 93, a prism 15, a hole mirror 13, a relay lens 16, a mirror 17, a light-receiving diaphragm 18, a collimator lens 19, a ring lens 20, and an image sensor 22. The ring lens 20 is composed of a ring-shaped lens portion and a light-shielding portion in which a light-shielding coating is applied to the area other than the lens portion. The ring lens 20 is optically conjugate with the pupil of the subject's eye E. The light-receiving diaphragm 18 and the image sensor 22 are conjugate with the fundus of the subject's eye E. The output from the image sensor 22 is input to the control unit 70.

[0047] In this embodiment, the prism 15 is disposed on the common optical axis of the projection optical system 10a and the light-receiving optical system 10b. For example, the measurement light beam from the projection optical system 10a passes through the prism 15 and enters the eye E, and the fundus-reflected light beam reflected by the fundus of the eye E also passes through the same prism 15. Therefore, in the subsequent optical system, the projection light beam and the fundus-reflected light beam (received light beam) are scanned in reverse as if there was no decentering of the projection light beam and the fundus-reflected light beam (received light beam) on the pupil.

[0048] <Subjective measurement optical system> The subjective measurement optical system 25 is used as part of a subjective measurement unit that subjectively measures the optical characteristics of the subject's eye E. In this embodiment, the ocular refractive power of the subject's eye E is measured as the optical characteristic of the subject's eye E. For example, the subjective measurement optical system 25 is composed of a light projection optical system 30 and a correction optical system 60.

[0049] <Projection optical system> 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 light projection lens 33, a light projection lens 34, a reflecting mirror 36, an objective lens 92, a dichroic mirror 35, a dichroic mirror 29, etc. The display 31 displays a visual target (a fixation target, a test visual target, etc.).

[0050] <Correction optical system> The correction optical system 60 is disposed in the optical path of the projection optical system 30. The correction optical system 60 changes the optical characteristics of the visual target light beam emitted from the display 31. For example, the correction optical system 60 includes an astigmatism correction optical system 63, a drive mechanism 39, and the like. The astigmatism correction optical system 63 is used to correct the cylindrical power and astigmatism axis angle of the subject's eye E. The astigmatism correction optical system 63 is disposed between the projection lens 33 and the projection lens 34. The astigmatism correction optical system 63 is composed of two positive cylindrical lenses 61a and 61b with the same focal length. The cylindrical lenses 61a and 61b are rotated independently around the optical axis L2 by the drive of the rotation mechanisms 62a and 62b.

[0051] In this embodiment, the astigmatism correcting optical system 63 is described using the cylindrical lens 61a and the cylindrical lens 61b as an example, but is not limited to this. The astigmatism correcting optical system 63 may be configured to be able to correct the cylindrical power, the astigmatic axis angle, etc. As an example, the corrective lens may be inserted into or removed from the optical path of the projection optical system 30.

[0052] The light source 11 and relay lens 12 included in the projection optical system 10a, the light-receiving diaphragm 18, collimator lens 19, ring lens 20, and image sensor 22 included in the light-receiving optical system 10b, and the display 31 included in the light-projection optical system 30 can be moved integrally in the optical axis direction by a drive mechanism 39. In other words, the display 31, light source 11, relay lens 12, light-receiving diaphragm 18, collimator lens 19, ring lens 20, and image sensor 22 are synchronized as a drive unit 95, and are moved integrally by the drive mechanism 39. The drive mechanism 39 is made up of a motor and a slide mechanism.

[0053] The drive mechanism 39 moves the drive unit 95 in the optical axis direction to move the display 31 in the optical axis L2 direction. This allows the subject's eye E to be fogged in objective measurement. In subjective measurement, the spherical power of the subject's eye E can be corrected by optically changing the presentation distance of the visual target relative to the subject's eye E. That is, the configuration that moves the display 31 in the optical axis L2 direction is used as a spherical correction optical system that corrects the spherical power of the subject's eye E, and the spherical power of the subject's eye E is corrected by changing the position of the display 31. The configuration of the spherical correction optical system may differ from that of this embodiment. For example, the spherical power may be corrected by placing multiple optical elements in the optical path. Furthermore, for example, the spherical power may be corrected by placing a lens in the optical path and moving the lens in the optical axis direction.

[0054] Furthermore, the drive mechanism 39 moves the drive unit 95 in the optical axis direction, thereby moving the light source 11, the relay lens 12, and the image sensor 22 from the light-receiving diaphragm 18 in the direction of the optical axis L1. As a result, the light source 11, the light-receiving diaphragm 18, and the image sensor 22 are arranged so as to be optically conjugate with the fundus of the subject's eye E. Regardless of the movement of the drive unit 95, the hole mirror 13 and the ring lens 20 are arranged so as to be conjugate with the pupil of the subject's eye E at a constant magnification. Therefore, the fundus-reflected light beam, which is the measurement light beam reflected from the projection optical system 10a, is always incident on the ring lens 20 of the light-receiving optical system 10b as a parallel light beam, and a ring-shaped light beam of the same size as the ring lens 20 is captured in focus by the image sensor 22, regardless of the ocular refractive power of the subject's eye E.

[0055] <First target projection optical system and second target projection optical system> The first target projection optical system 45 and the second target projection optical system 46 are disposed between the dichroic mirror 29 and a deflection mirror 81 (described later). The first target projection optical system 45 emits near-infrared light for projecting an alignment target at infinity onto the cornea of ​​the subject's eye E. The second target projection optical system 46 is disposed at a position different from the first target projection optical system 45, and emits near-infrared light for projecting an alignment target at finite distance onto the cornea of ​​the subject's eye. The near-infrared light (alignment light) emitted from the second target projection optical system 46 is also used as anterior eye imaging light for imaging the anterior eye of the subject's eye by the observation optical system 50.

[0056] <Observation optical system> The observation optical system (imaging optical system) 50 includes a dichroic mirror 29, an objective lens 103, an imaging lens 51, an imaging element 52, etc. The dichroic mirror 29 transmits the anterior segment observation light and the alignment light. The imaging element 52 has an imaging surface located at a position conjugate with the anterior segment of the subject's eye E. The output from the imaging element 52 is input to the control unit 70. As a result, an anterior segment image of the subject's eye E is captured by the imaging element 52 and displayed on the monitor 6a. The observation optical system 50 also serves as an optical system for detecting alignment target images formed on the cornea of ​​the subject's eye E by the first target projecting optical system 45 and the second target projecting optical system 46, and the position of the alignment target image is detected by the control unit 70.

[0057] <Internal structure of the optometry device> The internal configuration of the optometry apparatus 100 will be described. Fig. 3 is a schematic diagram of the inside of the optometry apparatus 100 as seen from the front. Fig. 4 is a schematic diagram of the inside of the optometry apparatus 100 as seen from the side. Fig. 5 is a schematic diagram of the inside of the optometry apparatus 100 as seen from above. For ease of explanation, Figs. 4 and 5 only show the optical axis of the measurement unit 7L for the left eye.

[0058] The optometry apparatus 100 includes an objective measurement unit. For example, the objective measurement unit includes the measurement unit 7, a deflection mirror 81, a reflection mirror 84, a concave mirror 85, etc. The optometry apparatus 100 also includes a subjective measurement unit. For example, the subjective measurement unit includes the measurement unit 7, a deflection mirror 81, a reflection mirror 84, a concave mirror 85, etc. The objective measurement unit and the subjective measurement unit are not limited to this configuration. For example, the configuration may not include the reflection mirror 84. In this case, the light beam from the measurement unit 7 may be irradiated from an oblique direction with respect to the optical axis L of the concave mirror 85 after passing through the deflection mirror 81. Furthermore, the configuration may include, for example, a half mirror. In this case, the light beam from the measurement unit 7 may be irradiated from an oblique direction with respect to the optical axis L of the concave mirror 85 via the half mirror.

[0059] For example, the deflection mirror 81 has a pair of left-eye deflection mirrors 81L and right-eye deflection mirrors 81R provided on the left and right sides, respectively. For example, the deflection mirror 81 is disposed between the corrective optical system 60 and the subject's eye E. That is, the corrective optical system 60 in this embodiment has a pair of left-eye corrective optical systems and right-eye corrective optical systems provided on the left and right sides, with the left-eye deflection mirror 81L disposed between the left-eye corrective optical system and the left eye EL, and the right-eye deflection mirror 81R disposed between the right-eye corrective optical system and the right eye ER. For example, the deflection mirror 81 is preferably disposed at a pupil conjugate position.

[0060] For example, the left-eye deflection mirror 81L reflects the light beam projected from the left-eye measurement unit 7L and guides it to the left eye EL. Also, for example, the left-eye deflection mirror 81L reflects the fundus-reflected light beam from the left eye EL and guides it to the left-eye measurement unit 7L. For example, the right-eye deflection mirror 81R reflects the light beam projected from the right-eye measurement unit 7R and guides it to the right eye ER. Also, for example, the right-eye deflection mirror 81R reflects the fundus-reflected light beam from the right eye ER and guides it to the right-eye measurement unit 7R.

[0061] For example, the deflection mirror 81 is rotationally moved by a driver 82. For example, the rotational movement of the deflection mirror 81 deflects an apparent light beam for forming an image of the visual target light beam in front of the subject's eye, and the position at which the image of the visual target light beam is formed can be optically corrected. For example, the driver 82 is made up of a motor or the like. For example, the driver 82 rotates the deflection mirror 81 about a rotation axis in the horizontal direction (X direction) and a rotation axis in the vertical direction (Y direction). That is, the driver 82 rotates the deflection mirror 81 in the X and Y directions. Note that the rotation of the deflection mirror 81 may be in either the horizontal direction or the vertical direction. For example, the driver 82 includes a driver 82L for driving the left-eye deflection mirror 81L and a driver 82R for driving the right-eye deflection mirror 81R.

[0062] In this embodiment, a configuration in which the deflection mirror 81 is used as a deflection member that reflects and guides the light beam projected from the measurement unit 7 to the subject's eye E has been described as an example, but the present invention is not limited to this. The deflection member may be a prism, a lens, or the like as long as it can reflect and guide the light beam projected from the measurement unit 7 to the subject's eye E.

[0063] Furthermore, for example, a plurality of deflection mirrors 81 may be provided in each of the optical path for the left eye and the optical path for the right eye. For example, two deflection mirrors may be provided in each of the optical path for the left eye and the optical path for the right eye (for example, two deflection mirrors may be provided in the optical path for the left eye). In this case, one deflection mirror may be rotated in the X direction, and the other deflection mirror may be rotated in the Y direction.

[0064] For example, the concave mirror 85 guides the visual target light beam that has passed through the corrective optical system 60 to the subject's eye E and forms an image of the visual target light beam that has passed through the corrective optical system 60 in front of the subject's eye E. For example, the concave mirror 85 is shared by the left eye measurement unit 7L and the right eye measurement unit 7R. For example, the concave mirror 85 is shared by the left eye optical path including the left eye corrective optical system and the right eye optical path including the right eye corrective optical system. That is, the concave mirror 85 is disposed at a position where both the left eye optical path including the left eye corrective optical system and the right eye optical path including the right eye corrective optical system pass through. Of course, the concave mirror 85 does not have to be shared by the left eye optical path and the right eye optical path. That is, a concave mirror may be provided in each of the left eye optical path including the left eye corrective optical system and the right eye optical path including the right eye corrective optical system.

[0065] <Optical paths between the objective and subjective measurement units> The optical path of the objective measurement unit will be described using the optical path for the left eye as an example. The optical path for the right eye has the same configuration as the optical path for the left eye. The measurement light beam emitted from the light source 11 of the projection optical system 10a reaches the left eye EL via each optical component. For example, the measurement light beam passes through the optical components from the relay lens 12 to the dichroic mirror 29, and is guided from the left eye measurement unit 7L to the left eye deflection mirror 81L. Furthermore, the visual target light beam is reflected by the left eye deflection mirror 81L and guided to the left eye EL via the reflection mirror 84 and the concave mirror 85. A spot-shaped point light source image is formed on the fundus of the left eye EL. At this time, the pupil projection image of the hole portion of the hole mirror 13 (the projected light beam on the pupil) is eccentrically rotated at high speed by the prism 15 rotating around the optical axis.

[0066] The measurement light beam is reflected and emitted from the fundus of the subject's eye E, and is guided to the left-eye measurement unit 7L via a concave mirror 85, a reflecting mirror 84, and a deflecting mirror 81. The measurement light beam is further reflected by the dichroic mirrors 29 and 35, condensed by an objective lens 93, and condensed again on the opening of the light-receiving diaphragm 18 via the rapidly rotating prism 15 and the optical components from the hole mirror 13 to the mirror 17. A ring-shaped image is formed on the image sensor 22 by the collimator lens 19 and the ring lens 20. The optical characteristics of the subject's eye E can be objectively measured by analyzing the ring-shaped image captured by the image sensor 22.

[0067] The optical path of the subjective measurement unit will be described using the optical path for the left eye as an example. The optical path for the right eye has the same configuration as the optical path for the left eye. The visual target light beam emitted from the display 31 of the subjective measurement optical system 25 reaches the left eye EL via each optical component. For example, the visual target light beam is guided from the left eye measurement unit 7L to the left eye deflection mirror 81L by passing through the optical components from the projection lens 33 to the dichroic mirror 29 in order. Furthermore, the visual target light beam is reflected by the left eye deflection mirror 81L and guided to the left eye EL via the reflecting mirror 84 and the concave mirror 85.

[0068] As a result, an image of the visual target light beam corrected by the corrective optical system 60 is formed on the fundus of the left eye EL, based on the eyeglass wearing position of the left eye EL (for example, approximately 12 mm from the corneal apex position). Therefore, performing spherical power adjustment by the corrective optical system (in this embodiment, driving the drive mechanism 39) in front of the eye is equivalent to placing the astigmatism correcting optical system 63 in front of the eye. The subject can collimate the image of the visual target light beam optically formed in front of the eye at a predetermined test distance via the concave mirror 85 in a natural state.

[0069] <1st and 2nd units> In this embodiment, the interior of the optometry apparatus 100 is composed of a first unit A1 and a second unit A2. For example, the first unit has a pair of left-eye units A1L and A1R, one on the left and one on the right. The left-eye unit A1L is a unit for integrally moving the left-eye measurement unit 7L and the left-eye deflection mirror 81L. That is, it is a unit for integrally moving the projection optical system 30 and the correction optical system 60 included in the left-eye measurement unit 7L, and the left-eye deflection mirror 81L. Similarly, the right-eye unit A1R is a unit for integrally moving the right-eye measurement unit 7R and the right-eye deflection mirror 81R. That is, it is a unit for integrally moving the projection optical system 30 and the correction optical system 60 included in the right-eye measurement unit 7R, and the right-eye deflection mirror 81R. For example, the second unit A2 is a unit for moving the first unit A1 (the left-eye unit A1L and the right-eye unit A1R), the reflecting mirror 84, and the concave mirror 85 as a unit.

[0070] For example, the first unit A1 is moved in three dimensions by the first moving unit 9 relative to a base 86 (bases 86L and 86R) fixed in the second unit A2. This allows the first unit A1 to move in three dimensions relative to the concave mirror 85, for example. Note that movement of the first unit A1 in at least one of the X and Y directions changes the incident position on the concave mirror 85 of the apparent light beam for forming an image of the visual target light beam in front of the subject's eye. Furthermore, movement of the first unit A1 in the Z direction changes the distance from the concave mirror 85 to the first unit A1, thereby changing the presentation distance of the image of the visual target light beam from the measurement unit 7.

[0071] For example, first moving unit 9 is composed of an X moving section, a Y moving section, a Z moving section, a drive section, etc. As an example, the X moving section may be a slide mechanism that moves the Y moving section in the X direction relative to base 86. Furthermore, the Y moving section may be a slide mechanism that moves the Z moving section in the Y direction relative to the X moving section. Furthermore, the Z moving section may be a slide mechanism that moves first unit A1 in the Z direction relative to the Y moving section. In other words, first unit A1 is connected to the Z moving section, and is moved in three-dimensional directions relative to base 86 via movement of the Z moving section, movement of the Y moving section, and movement of the X moving section. The drive section may include a plurality of motors, etc., for driving each moving section individually.

[0072] For example, the first moving unit 9 has a left-eye moving unit 9L for moving the left-eye unit A1L and a right-eye moving unit 9R for moving the right-eye unit A1R. This allows the left-eye unit A1L and the right-eye unit A1R to move independently in three-dimensional directions. The amount of movement of the left-eye unit A1L and the right-eye unit A1R in each direction is detected using the number of motor pulses, etc.

[0073] For example, the second unit A2 is moved in the Z direction by the second moving unit 8 relative to a base 87 fixed in the housing 2. This allows the second unit A2 to move in the Z direction relative to the eye E, for example. For example, by moving the second unit A2 in the Z direction, the first unit A1 (measurement unit 7) can be moved in the Z direction without changing the distance from the concave mirror 85 to the first unit A1. In other words, the first unit A1 (measurement unit 7) can be moved in the Z direction while maintaining the positional relationship between the concave mirror 85 and the first unit A1. For example, the second moving unit 8 is composed of a Z moving unit and a driving unit. As an example, the Z moving unit may be a slide mechanism that moves the second unit A2 in the Z direction relative to the base 87. In other words, the second unit A2 is connected to the Z moving unit and is moved in the Z direction relative to the base 87 via the movement of the Z moving unit. The driving unit may include a motor or the like for driving the Z moving unit. The amount of movement of the second unit A2 in the Z direction is detected using the number of pulses of the motor or the like.

[0074] 6 is a simplified diagram in which the optical components inside the optometry apparatus 100 are arranged in a straight line. For example, the first unit A1 is arranged at an initial position D1 inside the second unit A2. The initial position D1 is a position in the Z direction where, when an appropriate working distance WD is set from the eye E to the concave mirror 85, the pupil position of the eye E (i.e., the pupil position) and the pupil conjugate position of the subjective measurement unit have a fixed positional relationship. For example, the second unit A2 is arranged at a measurement position T1. The measurement position T1 is a position in the Z direction where an appropriate working distance WD is set from the eye E to the concave mirror 85.

[0075] In this embodiment, the second unit A2 is moved relative to the eye E and placed at the measurement position T1, and the eye E and the concave mirror 85 are maintained at an appropriate working distance WD, so that the first unit A1, which has been moved together with the second unit A2, is placed at the initial position D1. At this time, the distance from the eye E to the concave mirror 85 (i.e., the appropriate working distance WD) is the same as the distance wd from the concave mirror 85 to the first unit A1, and the eye E and the deflection mirror 81 are optically conjugate via the concave mirror 85. Furthermore, the optical magnification from the eye E to the concave mirror 85 and the optical magnification from the concave mirror 85 to the first unit A1 are equal. This allows the image of the visual target light beam to be projected well onto the eye E. <Control unit> FIG. 7 is a diagram showing the control system of the optometry apparatus 100. The control unit 70 includes a CPU (processor), RAM, ROM, etc. For example, the CPU controls each component in the optometry apparatus 100. For example, the RAM temporarily stores various types of information. For example, the ROM stores various programs, optotypes, initial values, etc. for controlling the operation of the optometry apparatus 100. The control unit 70 may be configured with multiple control units (i.e., multiple processors).

[0076] For example, the control unit 70 is electrically connected to various components such as the monitor 6a, light source 11, image sensor 22, display 31, image sensor 52, and non-volatile memory 75 (hereinafter, memory 75). Furthermore, for example, the control unit 70 is electrically connected to the drive unit of the first moving unit 9, the drive unit of the second moving unit 8, and the drive mechanism 39. For example, the memory 75 is a non-transitory storage medium that can retain its contents even when the power supply is cut off. For example, the memory 75 can be a hard disk drive, a flash ROM, a USB memory, or the like.

[0077] <Control action> The control operation of the optometry apparatus 100 will be described.

[0078] <Alignment of the patient's eye> The examiner instructs the subject to place their face against the forehead rest 4 and chin rest 5 and observe the presentation window 3. Since the subject's face is fixed, the subject's eye E is less likely to move in the X, Y, and Z directions. Next, the examiner operates the switch unit 6b to display a fixation target on the display 31 for fixating the subject's eye E. This causes the fixation target to be projected onto the subject's eye E.

[0079] Furthermore, the examiner operates the switch unit 6b to select a switch for performing alignment for the subject's eye E. The control unit 70 controls the first target projecting optical system 45, the second target projecting optical system 46, and the observation optical system 50 in response to an input signal from the switch unit 6b to project an alignment target onto the cornea of ​​the subject's eye E and acquire an anterior-segment image including an alignment target image of the subject's eye E. The control unit 70 also detects the corneal vertex position using the alignment target image in the anterior-segment image, and moves the first unit A1 and the second unit A2 based on the deviations in the X, Y, and Z directions of the corneal vertex position relative to the alignment reference position.

[0080] First, the movement of each unit in the Z direction will be described. FIG. 8 is a diagram showing the positions of the first unit A1 and the second unit A2 relative to the subject's eye E. FIG. 8(a) shows a state in which the second unit A2 is in a standby position relative to the subject's eye E. FIG. 8(b) shows a state in which the second unit A2 is in a measurement position T1 relative to the subject's eye E. As shown in FIG. 8(a), when alignment of the subject's eye E begins, the second unit A2 is in the standby position. For example, at this time, the concave mirror 85 is positioned a distance δz1 in the Z direction from position B, which provides an appropriate working distance WD between the subject's eye E and the concave mirror 85. Note that the distance δz1 can vary depending on the shape of the subject's eye E (for example, whether the eye is deep-set or bulging). Furthermore, since there is a difference in distance δz1 between the distance from the test eye E to the concave mirror 85 (i.e., working distance WD + distance δz1) and the distance wd from the concave mirror 85 to the first unit A1, the visual target is presented to the test eye E at a magnification different from the specified optical magnification.

[0081] The control unit 70 controls the drive unit of the second moving unit 8 to move the second unit A2 in the Z direction relative to the base 87 so that the eye E and the concave mirror 85 are aligned at an appropriate working distance WD. When the deviation of the corneal apex position in the Z direction falls within the allowable range, the control unit 70 stops controlling the drive unit of the second moving unit 8, thereby stopping the movement of the second unit A2. As a result, as shown in FIG. 8(b), the second unit A2 moves a distance δz1 relative to the eye E and is positioned at measurement position T1, and the concave mirror 85 is positioned at position B. The eye E and the concave mirror 85 are aligned at the appropriate working distance WD, completing the alignment of the first unit A1 (measurement unit 7) in the Z direction with the eye E.

[0082] The first unit A1 is located at an initial position D1 inside the second unit A2 via the base 86. The first unit A1 moves by a distance δz1 in accordance with the movement of the second unit A2, and the distance from the subject's eye E to the concave mirror 85 (working distance WD) and the distance wd from the concave mirror 85 to the first unit A1 are adjusted to be the same distance. As a result, the visual target is presented to the subject's eye E at a predetermined optical magnification.

[0083] Next, the movement of the first unit A1 in the X and Y directions will be described. The position of the subject's eye E changes depending on the interpupillary distance and the convergence angle (more specifically, the convergence angle according to the optical presentation distance of the visual target). In order to properly guide the visual target light beam to the subject's eye E, it is necessary to change the XY-direction incidence position of the visual target light beam relative to the concave mirror 85 based on the position of the subject's eye E. In other words, it is necessary to align the optical axis with the subject's eye E. Note that if there is a misalignment in the X and Y directions between the subject's eye E and the optical axis, the subject's eye E may not be able to properly view the visual target. For example, problems such as a missing part of the visual target or inability to properly fuse the visual target between the left and right eyes may occur.

[0084] The control unit 70 controls the drive units of the first moving unit 9 to move the first unit A1 in the X and Y directions relative to the base 86 in order to align the optical axis with the eye E. Furthermore, when the deviation of the corneal apex position in the X and Y directions falls within an allowable range, the control unit 70 stops control of the drive units of the first moving unit 9, thereby stopping the movement of the first unit A1. As a result, the first unit A1 is moved in the X and Y directions relative to the concave mirror 85, the optical axis is aligned with the eye E, and the alignment of the first unit A1 (measurement unit 7) in the X and Y directions with the eye E is completed. The eye E can properly view the optotype.

[0085] <Subjective measurement> When the alignment of the subject's eye E with the first unit A1 is completed, the examiner starts subjective measurement of the subject's eye E. The examiner operates the switch unit 6b to set the correction power for correcting the subject's eye E. As an example, the spherical power, cylindrical power, and astigmatic axis angle for correcting the subject's eye E may be selected based on the objective ocular refractive power (objective value) of the subject's eye E.

[0086] The control unit 70 controls at least one of the light projecting optical system 30 and the correction optical system 60 in response to a selection signal from the switch unit 6b. For example, the control unit 70 may drive the drive mechanism 39 to move the display 31 in the direction of the optical axis L2, thereby correcting the spherical power of the subject's eye E. Furthermore, for example, the control unit 70 may drive the rotation mechanisms 62a and 62b to rotate the cylindrical lenses 61a and 61b around the optical axis L2b, thereby correcting at least one of the cylindrical power and the astigmatic axis angle of the subject's eye E. As a result, the subject's eye E is corrected to a predetermined diopter value (for example, 0D).

[0087] The examiner operates the switch unit 6b to change the visual acuity value of the optotype presented to the subject's eye E, while checking whether the corrective power for correcting the subject's eye E is appropriate. For example, the examiner may ask the subject about the orientation of the optotype, and if the subject answers correctly, the visual acuity value is changed to one level higher (i.e., smaller), and if the subject answers incorrectly, the visual acuity value is changed to one level lower (i.e., larger). The control unit 70 changes the optotype displayed on the display 31 based on the change signal from the switch unit 6b. Note that if the corrective power for correcting the subject's eye E is inappropriate, the corrective power is changed. In this way, the subjective ocular refractive power (subjective value) of the subject's eye E is obtained.

[0088] <Tracking of the subject's eye> In the above, alignment is completed before starting subjective measurement of the subject's eye E, but the relationship between the subject's eye E and the first unit A1 is not necessarily maintained during subjective measurement. For example, if the subject's eye E moves or the presentation distance of the target is changed, the corneal vertex position may shift from the alignment reference position and fall outside the allowable range. Therefore, the control unit 70 may constantly detect the shift even during subjective measurement, and if the corneal vertex position falls outside the allowable range, the control unit 70 may cause the subject's eye E to track the first unit A1.

[0089] In this embodiment, the first moving unit 9 is controlled in response to small movements of the subject's eye E, and the subject's eye E is tracked by moving only the first unit A1. Regarding the movement of the subject's eye in the Z direction, it is also possible to move the second unit A2 by controlling the second moving unit 8, but the second unit A2 is large and has many optical members that move integrally, making it difficult to respond quickly.

[0090] 9A and 9B are diagrams showing the position of the first unit A1 relative to the concave mirror 85. FIG. 9A shows the state in which the first unit A2 is in the initial position D1. FIG. 9B shows the state in which the first unit A1 is in the moved position D2 after moving from the initial position D1. During subjective measurement, the first unit A1 is moved in at least one of the X, Y, and Z directions depending on the deviation of the corneal apex position, but for convenience, only the Z direction will be described here.

[0091] For example, when the subject's eye E moves a distance δz2 from the state shown in FIG. 9(a) toward the concave mirror 85, the state changes to the state shown in FIG. 9(b), and the distance from the subject's eye E to the concave mirror 85 changes to the working distance WD'. At this time, the control unit 70 controls the drive unit of the first moving unit 9 to move the first unit A1 a distance δz3 away from the concave mirror 85 relative to the base 86. The relationship between the displacement amount of the subject's eye E in the Z direction and the movement amount of the first unit A1 in the Z direction may be set in advance. This maintains the optical presentation distance of the target relative to the subject's eye E. Similarly, when the subject's eye E moves in the X and Y directions, the control unit 70 controls the drive unit of the first moving unit 9 to move the first unit A1 in the X and Y directions of the concave mirror 85 relative to the base 86. The relationship between the amount of deviation of the eye E in the X and Y directions and the amount of movement of the first unit A1 in the X and Y directions may be set in advance, so that the eye E and the optical axis are aligned, allowing the eye E to properly view the target.

[0092] <Optical aberration correction> In tracking the eye E, the relationship between the optical magnification at the distance from the eye E to the concave mirror 85 (working distance WD') and the distance from the concave mirror 85 to the first unit A1 (distance wd+distance Δz3) is slightly disrupted by moving the first unit A1 with respect to the concave mirror 85. This causes optical aberration, and an appropriate target may not be presented to the eye E.

[0093] Therefore, the control unit 70 sets a correction amount for correcting the change in optical magnification using position information of the first unit A1 in each direction. That is, the correction amount for correcting the change in optical magnification is set based on the movement amount in each direction from the initial position D1 to the movement position D2. As an example, a correction amount for correcting the optical magnification to 1 may be set. For example, the memory 75 may store a correction table based on experiments or simulations, in which the correction amount corresponds to the position information of the first unit A1.

[0094] For example, the control unit 70 may control the display on the display 31 based on the correction amount obtained from the correction table, and change the size of the target, etc. This allows an appropriate target to be presented, taking into account the optical aberration caused by the movement of the first unit A1.

[0095] As described above, for example, the subjective ophthalmology device in this embodiment controls a first moving means that moves a measurement unit including at least a projection optical system relative to a fixed optical member, and a second moving means that moves the measurement unit and the fixed optical member relative to the subject's eye while maintaining the positional relationship between the measurement unit and the fixed optical member, respectively, during alignment between the subject's eye and the measurement unit. For example, during alignment between the subject's eye and the optical axis of the projection optical system, the first moving means can be controlled to suppress the occurrence of optical aberrations that accompany movement of the measurement unit. Furthermore, during alignment for projecting an image of a target light beam onto the subject's eye at a predetermined optical magnification, the second moving means can be controlled to suppress changes in optical magnification. As a result, the optical characteristics of the subject's eye can be measured with high accuracy.

[0096] Furthermore, for example, the subjective ophthalmology device in this embodiment performs alignment by controlling the second moving means, and then performs alignment by controlling the first moving means. For example, by first controlling the second moving means and adjusting the optical magnification to a predetermined value, the movement of the measurement unit in the subsequent control of the first moving means is minimized, thereby reducing potential optical aberrations. Note that, for example, when the first moving means is controlled first, the measurement unit moves significantly relative to the fixed optical element, which tends to increase optical aberrations. Furthermore, to reduce this optical aberration by controlling the second moving means later, it becomes necessary to move the first moving means again. For example, after moving the measurement unit forward, it becomes necessary to move the measurement unit backward, taking into account the amount of forward movement of the measurement unit and the fixed optical element together. This tends to complicate control.

[0097] Furthermore, for example, the subjective ophthalmology device in this embodiment adjusts the alignment between the eye to be examined and the measurement unit by controlling the second moving means to perform coarse alignment of the measurement unit with the eye to be examined and by controlling the first moving means to perform fine alignment of the measurement unit with the eye to be examined. By controlling the second moving means to match the optical magnification to a predetermined value and then controlling the first moving means to match the optical axis of the eye to that of the projection optical system, it is possible to present an appropriate optotype to the eye to be examined.

[0098] Furthermore, for example, the subjective ophthalmology device in this embodiment performs alignment (coarse alignment and fine alignment) between the eye to be examined and the measurement unit, and then performs tracking to track the eye to be examined by controlling the first moving means. For example, by quickly responding to small movements of the eye to be examined during subjective measurement by controlling the first moving means, an appropriate optotype is presented to the eye to be examined.

[0099] Furthermore, for example, the subjective ophthalmology device in this embodiment moves the measurement unit and the fixed optical member at least in the front-to-back direction relative to the eye to be examined, and also moves the measurement unit at least in the left-to-right and up-to-down directions relative to the fixed optical member. For example, misalignment of the eye to be examined in the front-to-back direction has a large effect on the optical magnification, but by controlling the second moving means, it becomes easier to maintain a predetermined optical magnification. Furthermore, for example, misalignment of the eye to be examined in the left-to-right and up-to-down directions (i.e., misalignment between the eye to be examined and the optical axis) can be suppressed by controlling the first moving means.

[0100] Furthermore, for example, the subjective ophthalmology device in this embodiment acquires position information of the measurement unit and corrects optical aberrations that occur when the visual target light beam passes through the fixed optical member based on this position information. As a result, even if, for example, the measurement unit is moved relative to the fixed optical member, the relationship of the optical magnification is disrupted and optical aberrations occur, the optical axis of the projection optical system is properly aligned with the eye to be examined.

[0101] Furthermore, for example, the subjective ophthalmology device in this embodiment uses a concave mirror as the fixed optical element. For example, the concave mirror optically presents the visual target at a predetermined test distance, eliminating the need to position each component of the optical system at the actual distance. This allows the device to be made more compact. Note that, for example, when a concave mirror is used as the fixed optical element, optical aberrations associated with movement of the measurement unit relative to the fixed optical element are more likely to occur than when a lens or the like is used. However, by providing a first moving unit for aligning the optical axis of the projection optical system with the subject's eye and a second moving unit for aligning the image of the visual target light beam to be projected onto the subject's eye at a predetermined optical magnification, the measurement unit can be moved to further minimize the effects of optical aberrations.

[0102] <Example of transformation> In this embodiment, the first unit A1 is configured to move the deflection mirror 81 and the measurement unit 7 integrally relative to the concave mirror 85. However, the present invention is not limited to this. For example, only the measurement unit 7 may be moved relative to the concave mirror 85. In this case, a drive unit that can move the measurement unit 7 in the X, Y, and Z directions may be provided, and the measurement unit 7 may move in accordance with the rotation of the deflection mirror 81. As an example, the measurement unit 7 may be moved in the X and Y directions relative to the deflection mirror 81 to align the incident position of the visual target light beam (the optical axis of the visual target light beam) with a position corresponding to the interpupillary distance and convergence angle of the subject's eye E. Furthermore, the measurement unit 7 may be moved in the Z direction relative to the deflection mirror 81 to change the presentation distance of the visual target.

[0103] In this embodiment, the second moving unit 8 is configured to move the second unit A2 in the Z direction, but the present invention is not limited to this. The second moving unit 8 may be configured to move the second unit A2 at least in the Z direction. This is because the position of the subject's eye E in the Z direction changes depending on the shape of the subject's eye E (such as deep-set eyes or bulging eyes). For example, with this configuration, the optical magnification can be maintained regardless of the shape of the subject's eye E. The positions of the subject's eye E in the X and Y directions are roughly fixed by the forehead rest 4 and the chin rest 5, but the second unit A2 may of course be configured to be movable in the X and Y directions.

[0104] In this embodiment, the second moving unit 8 moves the concave mirror 85 and the first unit A1 integrally in the second unit A2, but the present invention is not limited to this. The second moving unit 8 may be configured to substantially move the concave mirror 85 and the first unit A1 integrally. For example, in this case, the second moving unit 8 may include a Z moving unit and a drive unit for moving the concave mirror 85 in the Z direction, and a Z moving unit and a drive unit for moving the first unit A1 in the Z direction. The second moving unit 8 may maintain the positional relationship between the concave mirror 85 and the first unit A1 and maintain a predetermined optical magnification by controlling the respective drive units so that the movement amount of the concave mirror 85 and the movement amount of the first unit A1 are the same.

[0105] In the present embodiment, the alignment of the subject's eye E is described by using an anterior-segment image of the anterior segment to detect a deviation between the corneal vertex position and the alignment reference position, thereby moving the first unit A1 in the X and Y directions. However, the present invention is not limited to this. For example, a facial image of the subject's face may be used to detect the interpupillary distance, thereby moving the first unit A1 in the X and Y directions. Furthermore, alignment may be performed using both an anterior-segment image and a facial image. In this case, the first unit A1 may be roughly aligned in the X and Y directions according to the interpupillary distance based on the facial image, and finely aligned in the X and Y directions according to a deviation from the alignment reference position based on the anterior-segment image.

[0106] In this embodiment, the alignment of the subject's eye E is described by taking as an example a configuration in which the second unit A2 is moved in the Z direction and then the first unit A1 is moved in the X and Y directions, but the present invention is not limited to this. For example, the alignment may be performed efficiently by moving the second unit A2 in the Z direction while simultaneously moving the first unit A1 in the X and Y directions.

[0107] In this embodiment, the configuration in which the subject's face is fixed with the forehead rest 4 and the chin rest 5 has been described as an example, but the present invention is not limited to this. For example, the configuration in which the subject's face is fixed with only the forehead rest 4 may be used. For example, in subjective measurement that proceeds based on the subject's answers, when the subject speaks with their chin resting against the chin rest 5, the subject's eye E is particularly likely to move in the Y direction. Such movement in the Y direction may be suppressed by using only the forehead rest 4 without using the chin rest 5. [Explanation of symbols]

[0108] 7 Measuring part 10 Objective measurement optical system 25 Subjective Measuring Optical System 70 Control Unit 75 memory 81 Deflecting mirror 84 Reflective mirror 85 Concave Mirror 100 Subjective optometry device

Claims

1. a light projection optical system that projects a visual target light beam toward the subject's eye; a correction optical system that changes the optical characteristics of the target light beam; a fixed optical member fixedly disposed in an optical path of the light projection optical system, the fixed optical member being for optically presenting an image of the visual target light beam to the subject's eye at a predetermined test distance; having A subjective optometry apparatus for subjectively measuring optical characteristics of the subject's eye, a first moving means for aligning an optical axis of the light projection optical system with the subject's eye by moving a measurement unit including at least the light projection optical system relative to the fixed optical member; a second moving means for moving the measurement unit and the fixed optical member relative to the subject's eye while maintaining a positional relationship between the measurement unit and the fixed optical member, thereby aligning the image of the visual target light beam on the subject's eye so as to project it at a predetermined optical magnification; a movement control means for controlling the first movement means and the second movement means in aligning the subject's eye with the measurement unit; A subjective eye examination device comprising:

2. In the subjective optometry device of claim 1, The subjective optometry apparatus according to claim 1, wherein the movement control means performs alignment under the control of the second movement means, and then performs alignment under the control of the first movement means.

3. In the subjective optometry device according to claim 1 or 2, The movement control means controls the second movement means to perform coarse alignment of the measurement unit with respect to the test eye, and controls the first movement means to perform fine alignment of the measurement unit with respect to the test eye, thereby adjusting the alignment between the test eye and the measurement unit.

4. In the subjective optometry device according to any one of claims 1 to 3, The movement control means controls the second movement means to move the measurement unit and the fixed optical member at least in the forward / backward direction relative to the test eye, and controls the first movement means to move the measurement unit at least in the left / right direction and the up / down direction relative to the fixed optical member.

5. In the subjective optometry device according to any one of claims 1 to 4, The measurement unit includes a pair of a left eye measurement unit and a right eye measurement unit, the fixed optical member is shared by an optical path of a visual target light beam from the left eye measurement unit and an optical path of a visual target light beam from the right eye measurement unit, The subjective optometry apparatus, wherein the second moving means moves the left eye measurement unit, the right eye measurement unit, and the fixed optical member together.

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