Optometer

Abstract

To provide an optometer capable of favorably measuring optical characteristics of a subject's eye.SOLUTION: An optometer for measuring optical characteristics of a subject's eye, comprises: an objective measurement optical system for objectively measuring the optical characteristics of the subject's eye; a subjective measurement optical system for subjectively measuring optical characteristics of the subject's eye; first control means for executing first alignment processing based on a first alignment allowable range for determining a positional deviation between the subject's eye and the objective measurement optical system; and second control means for executing second alignment processing based on a second alignment allowable range for determining a positional deviation between the subject's eye and the subjective measurement optical system, where the second alignment allowable range is wider than the first alignment allowable range.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to an optometry apparatus that measures optical characteristics of an eye to be examined. [Background technology]

[0002] An optometric apparatus is known that includes both an objective measurement optical system for objectively measuring the optical characteristics of a subject's eye and a subjective measurement optical system for subjectively measuring the optical characteristics of the subject's eye. In such an optometric apparatus, objective measurement using the objective measurement optical system is performed first, followed by subjective measurement using the subjective measurement optical system. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2018-047050 Summary of the Invention [Problem to be solved by the invention]

[0004] When measuring the eye to be examined, alignment is performed to adjust the positional relationship between the eye to be examined and the optometry device. For example, a tolerance is set for determining the misalignment between the eye to be examined and the optometry device, and if the deviation between them exceeds the tolerance, alignment is performed as appropriate. However, if the measurement of the eye to be examined is performed based on this tolerance, there are cases in which good measurement results of the optical characteristics of the eye to be examined cannot be obtained.

[0005] In view of the above-described conventional techniques, the present disclosure has as its technical object to provide an optometry apparatus that can satisfactorily 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. (1) An optometry device according to a first aspect of the present disclosure is an optometry device for measuring optical characteristics of an eye to be examined, comprising: a first light-projecting optical system that projects a measurement light beam onto a fundus of the eye to be examined; and a light-receiving optical system that receives a reflected light beam of the measurement light beam reflected by the fundus by a detector; an objective measurement optical system for objectively measuring the optical characteristics of the eye to be examined; a second light-projecting optical system that projects a visual target light beam toward the eye to be examined; and a corrective optical system that is disposed in an optical path of the second light-projecting optical system and changes the optical characteristics of the visual target light beam; The measurement device comprises a subjective measurement optical system for subjectively measuring the optical characteristics of the eye, a first control means for executing a first alignment process based on a first alignment tolerance range for determining the positional misalignment between the test eye and the objective measurement optical system, and a second control means for executing a second alignment process based on a second alignment tolerance range for determining the positional misalignment between the test eye and the subjective measurement optical system, and is characterized in that the second alignment tolerance range is a wider tolerance range than the first alignment tolerance range. (2) An optometry program according to a second aspect of the present disclosure includes an objective measurement optical system for objectively measuring optical characteristics of the subject's eye, the objective measurement optical system having a first light-projecting optical system that projects a measurement light beam onto a fundus of the subject's eye, and a light-receiving optical system that receives a reflected light beam of the measurement light beam reflected by the fundus using a detector, the objective measurement optical system having a second light-projecting optical system that projects a visual target light beam toward the subject's eye, and a corrective optical system that is disposed in an optical path of the second light-projecting optical system and changes the optical characteristics of the visual target light beam, the subjective measurement optical system having a first light-projecting optical system that projects a measurement light beam onto a fundus of the subject's eye, and a light-receiving optical system that receives a reflected light beam of the measurement light beam reflected by the fundus using a detector, the subjective measurement optical system having a second light-projecting optical system that projects a visual target light beam toward the subject's eye, and a corrective optical system that is disposed in an optical path of the second light-projecting optical system and changes the optical characteristics of the visual target light beam, the subjective measurement optical system having a first light-projecting optical system that projects a measurement light beam onto a fundus of the subject's eye, the corrective optical system having a first light-projecting optical system that projects a measurement light beam onto a fundus of the subject's eye, and a light-receiving optical system that receives a measurement light beam reflected by the fundus using a detector, the subjective measurement optical system having a second light-projecting optical system that projects a visual target light beam towards the subject's eye, and a corrective optical system that is disposed in an optical path of the second light-projecting optical system and changes the optical characteristics of the visual target light beam, the subjective measurement optical system having a first light-projecting optical system that projects a measurement light beam onto a fundus of the subject's eye, the subjective measurement optical system having a first light-projecting optical system that projects a measurement light beam onto a fundus of the subject's eye, the subjective measurement optical system having a first light-projecting optical system an optometry program for use in an optometry device, the optometry program being executed by a processor of the optometry device to perform a first alignment process based on a first alignment tolerance range for determining a positional misalignment between the subject's eye and the objective measurement optical system; and a second control step to perform a second alignment process based on a second alignment tolerance range for determining a positional misalignment between the subject's eye and the subjective measurement optical system, wherein the second alignment tolerance range is wider than the first alignment tolerance range. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is an external view of an optometry apparatus. [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. [Figure 7] 10 is an example of an anterior segment image of a left eye. [Figure 8] FIG. 10 is a diagram illustrating the alignment tolerance range for objective measurement. [Figure 9] FIG. 10 is a diagram illustrating the alignment tolerance range for subjective measurement. DETAILED DESCRIPTION OF THE INVENTION

[0008] <Summary> An overview of an optometry device according to an embodiment of the present disclosure will be described. In this embodiment, the left-right direction of the 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 grouped in < > below can be used independently or in association with each other.

[0009] The optometry apparatus of this embodiment is an apparatus capable of measuring the optical characteristics of a subject's eye. For example, the optometry apparatus may include an objective measurement optical system for objectively measuring the optical characteristics of the subject's eye. Alternatively, for example, the optometry apparatus may include a subjective measurement optical system for subjectively measuring the optical characteristics of the subject's eye.

[0010] <Objective measurement optical system> The ophthalmological examination apparatus of this embodiment may include an objective measuring optical system (e.g., the objective measuring optical system 10). For example, the objective measuring optical system may include a first light projecting optical system (e.g., the projection optical system 10a) that projects a measurement light beam onto the fundus of the eye to be examined, and a light receiving optical system (e.g., the light receiving optical system 10b) that receives the measurement light beam reflected by the fundus using a detector. Note that at least one of ocular refractive power (e.g., spherical power, cylindrical power, astigmatic axis angle, etc.), axial length, corneal shape, etc. may be measured as the objective optical characteristics.

[0011] The first light-projecting optical system may include a pair of first light-projecting optical systems, one for the left eye and one for the right eye. For example, the first light-projecting optical system for the left eye and the first light-projecting optical system for the right eye may be configured with the same components, or at least some of the components may be configured with different components. Furthermore, for example, the first light-projecting optical system for the left eye and the first light-projecting optical system for the right eye may be configured so that at least some of the components constituting each system are shared.

[0012] The first light receiving optical system may include a pair of first light receiving optical systems, one for the left eye and one for the right eye. For example, the first light receiving optical system for the left eye and the first light receiving optical system for the right eye may be composed of the same components, or at least some of the components may be composed of different components. Furthermore, for example, the first light receiving optical system for the left eye and the first light receiving optical system for the right eye may be configured so that at least some of the components constituting each system are shared.

[0013] <Subjective measurement optical system> The optometry device of this embodiment may include a subjective measuring means (e.g., a subjective measuring optical system 25). For example, the subjective measuring optical system may include a second light-projecting optical system (e.g., a light-projecting optical system 30) that projects a visual target light beam toward the subject's eye, and a corrective optical system (e.g., a corrective optical system 60) that is arranged in the optical path of the second light-projecting optical system and changes the optical characteristics of the visual target light beam. Note that the subjective optical characteristics that may be measured include 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.), etc.

[0014] <Second light projection optical system> The second light-projecting optical system projects a visual target light beam toward the subject's eye. The second light-projecting optical system may have at least one optical member that guides the visual target light beam toward the subject's eye.

[0015] The second light-projecting optical system may include a target presenting means. The target presenting means presents a target to the subject's eye. In this case, the second light-projecting optical system projects a target light beam emitted from the target presenting means toward the subject's eye. 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 subject's eye, allowing the target to be switched and positioned.

[0016] The second light-projecting optical system may include a pair of second light-projecting optical systems, one for the left eye and one for the right eye. For example, the second light-projecting optical system for the left eye and the second light-projecting optical system for the right eye may be configured with the same components, or at least some of the components may be configured with different components. Furthermore, for example, the second light-projecting optical system for the left eye and the second light-projecting optical system for the right eye may be configured so that at least some of the components constituting each system are shared.

[0017] <Correction optical system> The correction optical system is disposed in the optical path of the second light 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.

[0018] 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.

[0019] 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.

[0020] 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.

[0021] The correction optical system may be configured such that an optical element is disposed between the target presenting means and an optical member for guiding the target light beam from the second light projecting optical system toward the subject's eye, and the optical characteristics of the target 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 target light beam corrected by the correction optical system is guided to the subject's eye via the optical member.

[0022] The corrective optical system may include a pair of corrective optical systems, one for the left eye and one for the right eye. For example, the corrective optical system for the left eye and the other for the right eye may be composed of the same components, or at least some of the components may be composed of different components. Furthermore, for example, the corrective optical system for the left eye and the corrective optical system for the right eye may be configured so that at least some of the components constituting each optical system are shared.

[0023] <Measurement unit> The optometry device of this embodiment may include a measurement unit (e.g., measurement unit 7). The measurement unit includes an objective measurement optical system and a subjective measurement optical system, and has a pair of left and right measurement units, a left eye measurement unit (e.g., left eye measurement unit 7L) and a right eye measurement unit (e.g., right eye measurement unit 7R). That is, the device includes a left eye measurement unit including an objective measurement optical system for the left eye and a subjective measurement optical system for the left eye, and a right eye measurement unit including an objective measurement optical system for the right eye and a subjective measurement optical system for the right eye. The subjective measurement optical system for the left eye includes a second light-projecting optical system for the left eye and a corrective optical system for the left eye. The subjective measurement optical system for the right eye includes a second light-projecting optical system for the right eye and a corrective optical system for the right eye. For example, with this configuration, the left eye measurement unit can be aligned with the left eye, and the right eye measurement unit can be aligned with the right eye.

[0024] The optometry device of this embodiment has a pair of measurement units, one for the left eye and one for the right eye, so that it can project a visual target light beam from the second light-projecting optical system in the measurement unit for the left eye onto the left eye and a visual target light beam from the second light-projecting optical system in the measurement unit for the right eye onto the right eye, thereby enabling binocular fusion between the left eye and the right eye.

[0025] <Shared optical components> The optometry device of this embodiment may include a shared optical member. The shared optical member is an optical member shared by the optical path of the objective measurement optical system and the optical path of the subjective measurement optical system. For example, the shared optical member may guide a measurement light beam from a first light-projecting optical system in the objective measurement optical system to the subject's eye. The shared optical member may also guide a visual target light beam projected from a second light-projecting optical system in the subjective measurement optical system and corrected by the correction optical system to the subject's eye. This may optically present an image of the visual target light beam to the subject's eye at a predetermined examination distance.

[0026] The shared optical member may be an optical member fixedly disposed in the optical path of the first light-projecting optical system in the objective measurement optical system. The shared optical member may also be an optical member fixedly disposed in the optical path of the second light-projecting optical system in the subjective measurement optical system. The shared optical member may be shared by the optical paths of the measurement light beam and the visual target light beam from the measurement unit for the left eye and the measurement light beam and the visual target light beam from the measurement unit for the right eye. For example, the shared optical member may be at least one of a concave mirror (e.g., concave mirror 85), a lens, etc.

[0027] <Alignment tolerance> The ophthalmologic apparatus of this embodiment may have a first alignment tolerance range (e.g., alignment tolerance range B1). The first alignment tolerance range is a tolerance range for determining a positional misalignment between the subject's eye and the objective measurement optical system. For example, the first alignment tolerance range may be a tolerance range for determining a positional misalignment in the X direction between the subject's eye and the objective measurement optical system. Alternatively, the first alignment tolerance range may be a tolerance range for determining a positional misalignment in the Y direction between the subject's eye and the objective measurement optical system. Alternatively, the first alignment tolerance range may be a tolerance range for determining a positional misalignment in the Z direction between the subject's eye and the objective measurement optical system. Of course, the tolerance range may be a combination of these multiple directions.

[0028] The first alignment tolerance may be a tolerance range for determining a positional misalignment between the subject's eye and the first light-projecting optical system in the objective measurement optical system, or a tolerance range for determining a positional misalignment between the subject's eye and the light-receiving optical system in the objective measurement optical system, or, of course, a tolerance range for determining a positional misalignment between the subject's eye and both the first light-projecting optical system and the light-receiving optical system.

[0029] The ophthalmologic apparatus of this embodiment may have a second alignment tolerance range (e.g., alignment tolerance range B2). The second alignment tolerance range is a tolerance range for determining a positional misalignment between the subject's eye and the subjective measurement optical system. For example, the second alignment tolerance range may be a tolerance range for determining a positional misalignment in the X direction between the subject's eye and the subjective measurement optical system. It may also be a tolerance range for determining a positional misalignment in the Y direction between the subject's eye and the subjective measurement optical system. It may also be a tolerance range for determining a positional misalignment in the Z direction between the subject's eye and the subjective measurement optical system. Of course, the tolerance range may be a combination of these multiple directions.

[0030] The second alignment tolerance may be a tolerance for determining a positional misalignment between the subject's eye and the subjective measurement optical system so that the visual target is presented to the subject's eye. For example, the tolerance may be set to a range equivalent to a typical pupil diameter or a range smaller than a typical pupil diameter. This reduces the possibility that at least a portion of the visual target light beam from the second projection optical system directed toward the subject's eye is eclipsed, resulting in the visual target appearing missing to the subject's eye.

[0031] At least one of the first alignment tolerance range and the second alignment tolerance range may be a tolerance range of a predetermined fixed value. Alternatively, at least one of the first alignment tolerance range and the second alignment tolerance range may be a tolerance range of an arbitrary value set based on an operation signal for setting each tolerance range. In this case, for example, the examiner may operate an operation means (e.g., switch unit 6b) to output the operation signal. Alternatively, for example, the operation signal may be output by using an external storage means (e.g., an SD card, a USB memory, a server, a cloud, etc.) and reading data stored in the external storage means.

[0032] In this embodiment, the second alignment tolerance range is set to be wider than the first alignment tolerance range. For example, the second alignment tolerance range may be set to be wider than the first alignment tolerance range and approximately the same as a typical pupil diameter (or smaller than a typical pupil diameter). This allows each measurement to be performed within an alignment tolerance range appropriate for objective measurement using an objective measurement optical system and subjective measurement using a subjective measurement optical system. For example, in objective measurement, the positional misalignment between the subject's eye and the objective measurement optical system is finely adjusted, thereby obtaining accurate measurement results. In subjective measurement, a certain degree of positional misalignment between the subject's eye and the subjective measurement optical system is tolerated, reducing the frequency with which the optotype appears to move. This reduces the subject's discomfort and fatigue, and allows for good measurement results. Even if the subject's eye moves significantly and falls outside the second alignment tolerance range, the positional misalignment is adjusted appropriately, so the optotype is properly presented to the subject's eye.

[0033] <Control means> The optometry apparatus of this embodiment may include a first control unit (e.g., a control unit 70). The first control unit executes a first alignment process based on a first alignment tolerance range for determining a positional misalignment between the subject's eye and the objective measurement optical system. As the first alignment process, the first control unit may execute a process capable of eliminating the positional misalignment between the subject's eye and the objective measurement optical system. For example, the first control unit may adjust the relative positional relationship between the subject's eye and the objective measurement optical system. As an example, the objective measurement optical system may be moved relative to the subject's eye. Furthermore, for example, a face support unit (e.g., at least one of the forehead rest 4, the chin rest 5, the cheek rest, etc.) that supports at least a part of the subject's face may be operated to position the subject's eye in an appropriate position. Furthermore, for example, guide information for guiding the subject's eye to an appropriate position may be output. As an example, a message instructing the subject to move their face may be output by at least one of controlling a sound generation unit, a display unit, etc.

[0034] The optometry apparatus of this embodiment may include a second control means (e.g., a control unit 70). The second control means executes a second alignment process based on a second alignment tolerance range for determining a positional misalignment between the subject's eye and the subjective measurement optical system. As the second alignment process, the second control means may execute a process capable of eliminating a positional misalignment between the subject's eye and the subjective measurement optical system. For example, the second control means may adjust the relative positional relationship between the subject's eye and the subjective measurement optical system. As an example, the subjective measurement optical system may be moved relative to the subject's eye. Furthermore, for example, similar to the first control means, the second control means may operate a face support means to position the subject's eye in an appropriate position, or may output guide information to guide the subject's eye to an appropriate position.

[0035] In this embodiment, the first control means adjusts the relative positional relationship between the subject's eye and the objective measurement optical system as the first alignment process. For example, the objective measurement optical system may be moved at least in the X and Y directions. Of course, the objective measurement optical system may also be moved in the Z direction, for example. Note that the first control means may perform tracking control to align the objective measurement optical system with the subject's eye when the objective measurement optical system deviates from the subject's eye beyond the first alignment tolerance range.

[0036] In this embodiment, the second control means adjusts the relative positional relationship between the subject's eye and the subjective measurement optical system as the second alignment process. For example, the subjective measurement optical system may be moved at least in the X and Y directions. Of course, the subjective and objective measurement optical system may also be moved in the Z direction. For example, the second control means may perform tracking control to align the subjective measurement optical system with the subject's eye when the subjective measurement optical system deviates from the subject's eye beyond the second alignment tolerance range.

[0037] For example, since the subject's eye is prone to displacement in the X and Y directions, moving the objective measurement optical system and the subjective measurement optical system at least in the X and Y directions reduces the possibility that the visual target will not be presented appropriately to the subject's eye. Furthermore, moving the objective measurement optical system and the subjective measurement optical system in three dimensions relative to the subject's eye makes it possible to quickly position the objective measurement optical system and the subjective measurement optical system at appropriate positions according to the displacement of the subject's eye.

[0038] The first control means and the second control means may be combined into one unit, i.e., a single moving means may be used to perform the alignment process based on the first alignment tolerance range between the subject's eye and the objective measurement optical system and the alignment process based on the second alignment tolerance range between the subject's eye and the subjective measurement optical system.

[0039] <Change control measures> The optometry apparatus of this embodiment may include a change control means (e.g., a control unit 70). When the measurement of the subject's eye is switched from one of objective measurement using an objective measurement optical system and subjective measurement using a subjective measurement optical system to the other, the change control means changes the first alignment allowable range corresponding to the objective measurement and the second alignment allowable range corresponding to the subjective measurement. For example, when switching from objective measurement to subjective measurement of the subject's eye, the setting may be changed from the first alignment allowable range to the second alignment allowable range. Also, when switching from subjective measurement to objective measurement of the subject's eye, the setting may be changed from the second alignment allowable range to the first alignment allowable range. This allows each measurement of the subject's eye to proceed smoothly and obtain accurate measurement results.

[0040] The change control means may change the setting from the first alignment allowable range to the second alignment allowable range at any timing from the start to the end of the subjective measurement when switching from objective measurement to subjective measurement of the eye to be examined. Furthermore, the change control means may change the setting from the second alignment allowable range to the first alignment allowable range at any timing from the start to the end of the objective measurement when switching from subjective measurement to objective measurement of the eye to be examined.

[0041] The change control means may set each allowable range based on a change signal for changing the first alignment allowable range and the second alignment allowable range. For example, the change signal may be output by the examiner operating the operating means. As an example, the change signal may be output in response to an operation for starting at least one of the objective measurement and the subjective measurement, an operation for specifying at least one of the type of optotype to be presented to the subject's eye and the visual acuity value, an operation for specifying the correction power for correcting the subject's eye, or the like. Furthermore, for example, the change signal may be output based on a program for automatically proceeding at least one of the objective measurement and the subjective measurement.

[0042] The change control means may set the second alignment tolerance range when the optical characteristics of the subject's eye are objectively measured by the objective measurement optical system while the optical characteristics of the subject's eye are subjectively measured by the subjective measurement optical system. For example, the optical characteristics of the subject's eye may be objectively measured once while the optical characteristics of the subject's eye are subjectively measured. For example, the optical characteristics of the subject's eye may be objectively measured multiple times while the optical characteristics of the subject's eye are subjectively measured. For example, the multiple measurements may be performed at least once a predetermined time has elapsed since the start of subjective measurement, whenever the type of optotype presented to the subject's eye is changed, whenever the visual acuity value of the optotype presented to the subject's eye is changed, or whenever the correction power for correcting the eye is changed. For example, the optical characteristics of the subject's eye may be objectively measured continuously (in real time) while the optical characteristics of the subject's eye are subjectively measured. This makes it possible to obtain good measurement results from both objective and subjective measurements of the subject's eye.

[0043] The present disclosure is not limited to the devices described in the present embodiment. For example, terminal control software (programs) that perform the functions of the above embodiments may be supplied to a system or device via a network or various storage media, and a control device (e.g., a CPU) of the system or device may read and execute the program.

[0044] <Example> An example of an optometry apparatus according to this embodiment (hereinafter referred to as optometry apparatus) will be described.

[0045] 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.

[0046] 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.

[0047] <Measurement part>

[0048] 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 via the presentation window 3.

[0049] 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.

[0050] <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.

[0051] 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.

[0052] 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.

[0053] 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.

[0054] <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.

[0055] <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.).

[0056] <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.

[0057] 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.

[0058] 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.

[0059] 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.

[0060] 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.

[0061] <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.

[0062] <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.

[0063] <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.

[0064] 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.

[0065] 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.

[0066] 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.

[0067] 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.

[0068] 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.

[0069] 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, a configuration in which two deflection mirrors are provided in each of the optical path for the left eye and the optical path for the right eye (for example, a configuration in which two deflection mirrors are provided in the optical path for the left eye) may be used. In this case, one deflection mirror may be rotated in the X direction, and the other deflection mirror may be rotated in the Y direction. For example, by rotating the deflection mirror 81, the apparent light beam for forming an image of the visual target light beam in front of the subject's eye can be deflected, and the position where the image of the visual target light beam is formed can be optically corrected.

[0070] 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. For example, the concave mirror 85 guides the visual target light beam that has passed through the correction optical system 60 to the subject's eye E, and forms an image of the visual target light beam that has passed through the correction optical system 60 in front of the subject's eye E.

[0071] The deflection mirror 81 is driven by a drive unit 83 (e.g., a motor or the like). For example, the drive unit 83 has a left drive unit 83L for driving the left-eye deflection mirror 81L and a right drive unit 83R for driving the right-eye deflection mirror 81R. Driving by the drive unit 83 moves each deflection mirror in the X direction. For example, moving the left-eye deflection mirror 81L and the right-eye deflection mirror 81R changes the distance between the left-eye deflection mirror 81L and the right-eye deflection mirror 81R, and the distance in the X direction between the left-eye optical path and the right-eye optical path can be changed in accordance with the interpupillary distance of the subject's eye E.

[0072] The measurement unit 7 is driven by a drive unit 9 (e.g., a motor, etc.). For example, the drive unit 9 has a left drive unit 9L for driving the left eye measurement unit 7L and a right drive unit 9R for driving the right eye measurement unit 7R. When the drive unit 9 is driven, each measurement unit moves in the X direction. For example, when the left eye measurement unit 7L and the right eye measurement unit 7R are moved, the distance between each measurement unit and the deflection mirror 81 changes, and the presentation position of the visual target light beam from each measurement unit in the Z direction changes. This allows the measurement unit 7 to be adjusted in the Z direction so that the visual target light beam corrected by the correction optical system 60 is guided to the subject's eye E and an image of the visual target light beam corrected by the correction optical system 60 is formed on the fundus of the subject's eye E.

[0073] <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.

[0074] 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.

[0075] 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.

[0076] 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.

[0077] <Control unit> 6 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).

[0078] 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 units 9, 82, 83, and 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.

[0079] <Control action> The control operation of the optometry apparatus 100 will be described.

[0080] The examiner instructs the subject to place their face against the forehead rest 4 and chin rest 5 and observe the presentation window 3. The examiner also operates the switch unit 6b to operate a switch to start measurement of the subject's eye E. Based on the operation signal from the switch unit 6b, the control unit 70 performs initial alignment with the subject's eye E, and then automatically proceeds with the objective measurement and subjective measurement.

[0081] <Initial alignment of the patient's eye> In response to an operation signal for starting measurement of the subject's eye E, the control unit 70 displays a fixation target for the left eye on the display 31 of the left eye measurement unit 7L. Also, it displays a fixation target for the right eye on the display 31 of the right eye measurement unit 7R. As a result, the left and right eyes are in a state of binocular fusion of the fixation targets.

[0082] The control unit 70 projects an alignment index image by the first index projecting optical system 45 and the second index projecting optical system 46 of the left eye measurement unit 7L onto the cornea of ​​the left eye. The control unit 70 also detects the deviations of the left eye measurement unit 7L relative to the left eye in the X, Y, and Z directions based on the alignment index image, and moves the left eye measurement unit 7L. Similarly, the control unit 70 projects an alignment index image onto the cornea of ​​the right eye, and moves the right eye measurement unit 7R based on the alignment index image.

[0083] 7 is an example of an anterior-segment image 300 of the left eye. For example, the center position of the anterior-segment image 300, which coincides with the optical axis L4L, is set as the alignment reference position N. Also, for example, a predetermined XY range based on the alignment reference position N is set as the alignment tolerance range A1 for determining whether the alignment in the XY directions is appropriate. Also, for example, a predetermined Z range based on the alignment reference position N is set as the alignment tolerance range (not shown) for determining whether the alignment in the Z direction is appropriate.

[0084] The control unit 70 detects the XY center coordinates of the alignment target image as the corneal vertex position K, and determines the amount of deviation Δd between the corneal vertex position K and the alignment reference position N, thereby detecting whether the corneal vertex position K is misaligned with respect to the alignment reference position N. The control unit 70 also moves the left-eye measurement unit 7L in the X and Y directions so that the amount of deviation Δd falls within the alignment tolerance range A1. The control unit 70 also moves the left-eye measurement unit 7L in the Z direction so that the image ratio between the image spacing of the alignment target image at infinity and the image spacing of the alignment target image at finite distance falls within the alignment tolerance range (not shown). When the amount of deviation Δd and the image ratio fall within the tolerance range, the movement of the left-eye measurement unit 7L is stopped.

[0085] For example, in addition to the alignment between the left eye and the left eye measurement unit 7L, the alignment between the right eye and the right eye measurement unit 7R is also performed by similar control based on the alignment tolerance range.

[0086] <Objective measurement> When the initial alignment of the left eye with the left-eye measurement unit 7L and the initial alignment of the right eye with the right-eye measurement unit 7R are completed, the control unit 70 automatically starts objective measurement for the left and right eyes. For example, the fixation targets are still presented to the left and right eyes, and objective measurement for the left and right eyes is performed in parallel with the fixation targets fused binocularly.

[0087] At this time, the control unit 70 sets an alignment tolerance range B1 for objective measurement based on the alignment reference position N, and causes the left eye measurement unit 7L and the right eye measurement unit 7R to track based on this alignment tolerance range B1 (i.e., performs tracking control). Note that the alignment tolerance range B1 for objective measurement may be the same tolerance range as the above-mentioned alignment tolerance range A1. In this case, tracking control based on the alignment tolerance range A1 is performed continuously from the initial alignment.

[0088] FIG. 8 illustrates the alignment tolerance B1 for objective measurement. Objective measurement requires more precise alignment between the subject's eye and each measurement unit. For example, if the subject's face or the subject's line of sight moves, disrupting the predetermined positional relationship between the subject's eye and each measurement unit, the size and shape of the ring image will change, resulting in inaccurate measurement results. In particular, if the measurement units are significantly misaligned with respect to the subject's eye, the effect on the ring image will be significant, resulting in the calculated measurement result being a value different from the actual eye refractive power. For this reason, the alignment tolerance B1 for objective measurement is set to a narrower tolerance than the alignment tolerance B2 for subjective measurement (described below). For example, the alignment tolerance B1 may be set within a range of φ0.5 mm from the alignment reference position N. Of course, the range may be different from φ0.5 mm.

[0089] In objective measurement, a preliminary measurement may be performed first, followed by a main measurement. In the preliminary measurement of the left eye, the eye refractive power is measured with a fixation target positioned at a predetermined presentation distance. For example, the control unit 70 positions the display 31 of the left eye measurement unit 7L at an initial position that is optically far enough from the left eye and corresponds to the far point of the 0D eye. The control unit 70 also irradiates the left eye with a measurement beam from the light source 11 of the projection optical system 10a, and performs image analysis on the ring image captured by the image sensor 22 of the light receiving optical system 10b. For example, the control unit 70 thins the ring image to determine the eye refractive power in each meridian direction, performs predetermined processing on the eye refractive power, and obtains at least the spherical power (the spherical power in the preliminary measurement).

[0090] Next, fogging is added to the left eye. For example, the control unit 70 positions the display 31 of the left eye measurement unit 7L at the fogging start position where the left eye is in focus, according to the spherical power of the preliminary measurement of the left eye. The left eye can clearly observe the fixation target. Thereafter, the control unit 70 moves the fixation target from the fogging start position. The left eye no longer focuses on the fixation target, and fogging is added. This releases accommodation of the left eye, and the eye refractive power approaches its true value.

[0091] In the main measurement of the subject's eye E, the ocular refractive power is measured with the left eye clouded. For example, the control unit 70 causes the image sensor 22 to continuously capture ring images at predetermined intervals. In addition, for example, the control unit 70 adds the ring images to reduce noise light, and acquires the ocular refractive power of the left eye (spherical power, cylindrical power, and astigmatic axis angle in the main measurement) in the same manner as in the preliminary measurement, and stores them in the memory 75.

[0092] For example, along with the measurement of the objective refractive power of the left eye, the measurement of the objective refractive power of the right eye is also performed by the same control.

[0093] During the preliminary measurement and main measurement for the left and right eyes, tracking control is performed for each of the left and right eyes based on the alignment tolerance range B1 for objective measurement. The control unit 70 constantly detects, from the anterior eye image 300, whether the deviation amount Δd between the corneal vertex position K of the left eye and the alignment reference position N falls within the alignment tolerance range B1. Furthermore, if the deviation amount Δd falls outside the alignment tolerance range B1, the control unit 70 resumes alignment and moves the left eye measurement unit 7L. If the deviation amount Δd falls within the alignment tolerance range B1, the control unit 70 stops the movement of the left eye measurement unit 7L. For the right eye as well, the right eye measurement unit 7R is constantly moved and stopped based on the deviation amount Δd.

[0094] Note that the subject may perceive the fixation target as moving because the position of the fixation target relative to the left and right eyes is adjusted in accordance with the tracking control of the control unit 70. However, since the time from the start of the objective measurement to obtaining the measurement results is short, the subject is unlikely to notice the movement of the fixation target. Therefore, in the objective measurement, even if the alignment tolerance range B1 is set narrow, the subject is unlikely to feel annoyed or fatigued by the movement of the fixation target, and the objective ocular refractive power (objective value) can be appropriately obtained. <Subjective measurement> When the control unit 70 acquires the objective ocular refractive powers of the left and right eyes, it automatically starts subjective measurements for the left and right eyes. For example, the subjective measurements for the left eye and the right eye are performed in sequence.

[0095] The control unit 70 turns off the displays 31 of each measurement unit and stops presenting the fixation target. The control unit 70 also sets the spherical power, cylindrical power, and astigmatic axis angle based on the objective ocular refractive power of the left eye. For example, the spherical power of the left eye may be corrected by moving the display 31 in the direction of the optical axis L2. Furthermore, for example, at least one of the cylindrical power and the astigmatic axis angle of the left eye may be corrected by rotating the cylindrical lenses 61a and 61b around the optical axis L2. This corrects the left eye to a predetermined diopter value (e.g., 0D). Similarly, the control unit 70 corrects the right eye to a predetermined diopter value (e.g., 0D) based on the objective ocular refractive power of the right eye.

[0096] Next, the control unit 70 displays a predetermined test optotype and a background image on the display 31 of the left eye measurement unit 7L, and also displays the background image on the display 31 of the right eye measurement unit 7R. For example, the background image may be a white image. Of course, it may also be an image other than a white image. This makes it possible to present the test optotype only to the left eye while creating a state of binocular vision without blocking the view in front of the left and right eyes.

[0097] Furthermore, after presenting a test target or background image to the subject's eye E, the control unit 70 detects whether the deviation amount Δd between the corneal vertex position K of the left eye and the right eye and the alignment reference position N falls within the alignment tolerance range B1 for objective measurement. If the deviation amount Δd is outside the alignment tolerance range B1, the control unit 70 resumes alignment and moves the left eye measurement unit 7L and the right eye measurement unit 7R. If the deviation amount Δd falls within the alignment tolerance range B1, the control unit 70 stops moving the left eye measurement unit 7L and the right eye measurement unit 7R.

[0098] In subjective measurement of the subject's eye E, the test target is switched and the test target presentation distance is changed. This means that the time from the start of subjective measurement to obtaining the measurement results is longer than that of objective measurement, and the subject's face and gaze of the subject's eye E move more frequently. If the subjective measurement is continued while the alignment tolerance B1 for objective measurement is set, the subject may easily notice the movement of the test target, which may cause annoyance and fatigue, preventing accurate measurement results. Therefore, the control unit 70 finely aligns the subject's eye and each measurement unit through alignment based on the alignment tolerance B1 for objective measurement, and then changes the setting to the alignment tolerance B2 for subjective measurement. The subjective ocular refractive powers of the left and right eyes are obtained while tracking the left and right eye measurement units 7L and 7R based on the alignment tolerance B2 for subjective measurement.

[0099] FIG. 9 is a diagram illustrating the alignment tolerance B2 for subjective measurement. In subjective measurement of the subject's eye E, measurement can proceed as long as each measurement unit is aligned to the extent that the subject's eye E can recognize the test target. More specifically, even if the subject's face or the subject's line of sight moves and the predetermined positional relationship between the subject's eye E and the measurement unit 7 is disrupted, misalignment of each measurement unit is acceptable as long as no part of the test target is missing. For this reason, the alignment tolerance B2 for subjective measurement is set to a wider tolerance than the alignment tolerance B1 for objective measurement. As an example, a tolerance range between φ2.0 mm and φ4.0 mm may be set based on the alignment reference position N. Of course, the tolerance may be smaller than φ2.0 mm or larger than φ4.0 mm.

[0100] The examiner operates the switch unit 6b to change the visual acuity value of the test optotype presented to the left eye, while checking whether the corrective power for correcting the left eye is appropriate. For example, the examiner may ask the subject about the orientation of the test 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 test 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 left eye EL is inappropriate, the corrective power is changed. This allows the subjective ocular refractive power (subjective value) of the left eye to be obtained.

[0101] For example, similar to the measurement of the subjective ocular refractive power of the left eye, the subjective ocular refractive power (subjective value) of the right eye is obtained by presenting a test target only to the right eye while the left and right eyes are in binocular vision, and checking whether the corrective power is appropriate while switching the visual acuity value of the test target presented to the right eye.

[0102] During subjective measurement of the left or right eye, tracking control is performed for each of the left and right eyes based on the subjective measurement alignment tolerance B2. The control unit 70 constantly detects, from the anterior eye image 300, whether the deviation amount Δd between the corneal vertex position K of the left eye and the alignment reference position N falls within the alignment tolerance B2. Furthermore, if the deviation amount Δd falls outside the alignment tolerance B2 due to, for example, movement of the line of sight of the subject's eye E, the control unit 70 resumes alignment and moves the left eye measurement unit 7L and the right eye measurement unit 7R. If the deviation amount Δd falls within the alignment tolerance B2, the control unit 70 stops the movement of the left eye measurement unit 7L. For the right eye, the right eye measurement unit 7R is also constantly moved and stopped based on the deviation amount Δd.

[0103] When the position of the test target relative to the left and right eyes is adjusted in accordance with the tracking control of the control unit 70, the test target may appear to move to the subject. However, by setting a wide alignment tolerance range B2 for subjective measurement, the left and right eyes are less likely to deviate from the alignment tolerance range B2, and the number of times tracking control is performed is reduced. Therefore, even in subjective measurement, the subject is less likely to feel annoyed or fatigued by the movement of the test target, and appropriate measurement results can be obtained.

[0104] <Measurement of binocular vision function based on binocular fusion state> In subjective measurement of the subject's eye E, binocular vision can be measured by fusing the left and right eyes while creating a binocular vision state without blocking the view in front of the left and right eyes. For example, the binocular vision function of the subject's eye E may be at least one of information such as binocular balance, stereopsis, strabismus, and aniseikonia. Based on an operation signal from the switch unit 6b, the control unit 70 displays a background image and a predetermined test target on the display 31 of the left eye measurement unit 7L and the display 31 of the right eye measurement unit 7R, respectively. In other words, the same background image and the same test target are presented to the left and right eyes.

[0105] In this way, even when binocularly fusing the left and right eyes in subjective measurement of the subject's eye E, tracking control is performed for the left and right eyes based on the subjective measurement alignment tolerance B2. For example, if the presentation position of the test target for the left and right eyes is finely adjusted, the test target may appear to move, which can cause annoyance and fatigue, and the binocular fusion may be canceled, causing the test target to appear separated. By setting the subjective measurement alignment tolerance B2 to a wide tolerance range, it is possible to prevent the binocular fusion state from being canceled and make it difficult to separate the test target.

[0106] <Objective measurement during subjective measurement> Furthermore, subjective measurement of the subject's eye E can be performed in parallel with objective measurement of the subject's eye E. In other words, while the ocular refractive power of the subject's eye E is being measured subjectively, the ocular refractive power of the subject's eye E can be measured objectively. For example, accommodation information of the subject's eye E can be obtained from the change between the ocular refractive power (first ocular refractive power) obtained by objective measurement of the subject's eye E and the ocular refractive power (second ocular refractive power) obtained by objective measurement during the subjective measurement of the subject's eye E. The accommodation information of the subject's eye E may be information related to the accommodation function of the subject's eye E. For example, it may be information such as whether the subject's eye E is in an accommodative state, and how the accommodative state has changed.

[0107] In this way, when objective measurement and subjective measurement of the subject's eye E are performed in parallel, the alignment tolerance B2 for the subjective measurement is set. In other words, when both objective measurement and subjective measurement are performed, the alignment tolerance B2 for the subjective measurement takes priority. For example, if the alignment tolerance B1 for the objective measurement is set for the objective measurement optical system, the refractive power of the second eye cannot be obtained if the deviation amount Δd exceeds the alignment tolerance B1 but remains within the alignment tolerance B2 for a certain period of time. By setting the alignment tolerances for the objective measurement and the subjective measurement to the same tolerance, the refractive power of the second eye can be obtained smoothly.

[0108] For example, the control unit 70 detects whether the deviation amount Δd is within the alignment tolerance range B2, and moves the left eye measurement unit 7L and the right eye measurement unit 7R so that the deviation amount Δd falls within the alignment tolerance range B2. Furthermore, the control unit 70 acquires the refractive power of the second eye at at least any timing from the start to the end of the subjective measurement (for example, the timing at which the subjective measurement starts, the timing at which the test target is switched, the timing at which the correction power is switched, etc.). For example, accommodation information may be acquired by calculating the difference between the refractive power of the first eye and the refractive power of the second eye.

[0109] As described above, for example, the optometry apparatus of this embodiment performs a first alignment process based on a first alignment tolerance range to determine the misalignment between the subject's eye and the objective measurement optical system, and a second alignment process based on a second alignment tolerance range to determine the misalignment between the subject's eye and the subjective measurement optical system, with the second alignment tolerance range being a wider tolerance range than the first alignment tolerance range. For example, in objective measurement, the misalignment between the subject's eye and the objective measurement optical system is finely adjusted based on the first alignment tolerance range, allowing for accurate measurement results. Also, for example, in subjective measurement, the misalignment between the subject's eye and the subjective measurement optical system is tolerated to a certain extent based on the second alignment tolerance range, reducing the frequency with which the optotype appears to move, allowing for better measurement results.

[0110] Furthermore, for example, the optometry apparatus of this embodiment adjusts the relative positional relationship between the subject's eye and the objective measurement optical system as the first alignment process, and adjusts the relative positional relationship between the subject's eye and the subjective measurement optical system as the second alignment process, thereby enabling each optical system to be quickly positioned at an appropriate position according to the positional deviation between the subject's eye and the objective measurement optical system and the subjective measurement optical system.

[0111] Furthermore, for example, the optometry apparatus of this embodiment changes the first alignment tolerance range corresponding to the objective measurement and the second alignment tolerance range corresponding to the subjective measurement when the measurement of the subject's eye is switched from one of objective measurement using the objective measurement optical system to subjective measurement using the subjective measurement optical system. This allows each measurement to proceed smoothly in the series of objective and subjective measurements of the subject's eye. For example, in objective measurement, the measurement proceeds smoothly by precisely moving the objective optical system. For example, in subjective measurement, the annoyance and fatigue caused by the test target appearing to move are reduced, allowing the measurement to proceed smoothly.

[0112] Furthermore, for example, the optometry apparatus of this embodiment sets a second alignment tolerance range for subjective measurement when objectively measuring the optical characteristics of the subject's eye while subjectively measuring the optical characteristics of the subject's eye. For example, in this configuration, if a first alignment tolerance range for objective measurement is set (in other words, the first alignment tolerance range is prioritized), problems such as the inconvenience of moving the test target cannot be resolved. For example, in this configuration, if the alignment tolerance ranges for objective measurement and subjective measurement are set to different tolerance ranges, it may be impossible to obtain the measurement results of the objective measurement when the measurement falls outside the first alignment tolerance range for objective measurement but within the second alignment tolerance range for subjective measurement. By setting a second alignment tolerance range, it is possible to obtain good measurement results for both objective measurement and subjective measurement.

[0113] Furthermore, for example, the optometry device of this embodiment includes an objective measurement optical system and a subjective measurement optical system, and is equipped with a measurement unit having a pair of left and right measurement units, and aligns the left eye measurement unit with the left eye and the right eye measurement unit with the right eye. This makes it possible to perform not only monocular vision measurement using one of the left eye measurement unit and the right eye measurement unit, but also binocular vision measurement using both the left eye measurement unit and the right eye measurement unit.

[0114] Furthermore, for example, the optometry device of this embodiment projects a target light beam from the left eye measurement unit onto the left eye and a target light beam from the right eye measurement unit onto the right eye, enabling binocular fusion between the left and right eyes. For example, when measuring the binocular vision function of the subject's eyes, if the alignment tolerance range of the subjective measurement is narrow and the test target appears to move, the fusion state between the two eyes may be canceled, causing the left and right test targets to appear separated, which can be annoying. However, by setting a wide alignment tolerance range for the subjective measurement, separation of the test target is suppressed, allowing for accurate measurement results.

[0115] <Example of transformation> 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 a 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.

[0116] In this embodiment, an example has been described in which an alignment tolerance range B1 in the XY directions for objective measurement and an alignment tolerance range B2 in the XY directions for subjective measurement are set for the subject's eye E, but this is not limiting. For example, because the subject's face is resting against the forehead rest 4 and chin rest 5 and is therefore difficult to move, alignment tolerance ranges may be set only in the XY directions in objective and subjective measurements to accommodate at least movement of the line of sight. However, because the subject's face may move, an alignment tolerance range may also be set in the Z direction. Even in this case, the alignment tolerance range in the Z direction for subjective measurement may be set wider than the alignment tolerance range in the Z direction for objective measurement.

[0117] In this embodiment, a configuration has been described in which the alignment tolerance range B1 for objective measurement and the alignment tolerance range B2 for subjective measurement are set to fixed values ​​in advance, but this is not limiting. For example, the alignment tolerance range B1 for objective measurement may be changeable to any value. Also, for example, the alignment tolerance range B2 for subjective measurement may be changeable to any value. In this embodiment, at least the alignment tolerance range B2 may be changeable to any value.

[0118] For example, if the alignment tolerance is larger than the pupil diameter of the subject's eye E, even if the measurement unit 7 is moved so that the corneal vertex position K of the subject's eye E falls within the alignment tolerance, the target light beam from the subjective measurement optical system may be projected outside the pupil diameter, potentially preventing the subject's eye E from recognizing the test target. In particular, if the subject's eye E has a small pupil, the alignment tolerance B1 for objective measurement is set to a narrow tolerance, making it less likely to be a problem, whereas the alignment tolerance B2 for subjective measurement is set to a wide tolerance, making it more likely to be a problem. Therefore, the examiner can arbitrarily change the alignment tolerance B2 depending on the pupil diameter of the subject's eye E, thereby reducing the annoyance of the test target appearing to move during subjective measurement and obtaining accurate measurement results.

[0119] The subjective measurement alignment tolerance B2 may be automatically changed to an appropriate value depending on the pupil diameter of the subject's eye E. In this case, the control unit 70 acquires the pupil diameter of the subject's eye E and changes the alignment tolerance B2 based on the pupil diameter. For example, the pupil diameter of the subject's eye E may be acquired by detecting a pixel position corresponding to the pupil or a pixel position corresponding to the iris based on luminance information of the anterior eye image 300. Alternatively, for example, the pupil diameter of the subject's eye E may be acquired by the examiner operating the switch unit 6b to input the value. The control unit 70 may change the alignment tolerance B2 by setting a predetermined alignment tolerance associated with the pupil diameter.

[0120] In this embodiment, when the deviation amount Δd between the subject's eye E and the alignment reference position N deviates from the alignment tolerance range B2 during subjective measurement of the subject's eye E, the measurement unit 7 is moved so that the deviation amount Δd falls within the alignment tolerance range B2. However, this is not limiting. For example, when the deviation amount Δd deviates from the alignment tolerance range B2, the measurement unit 7 may be moved so that the deviation amount Δd falls within the alignment tolerance range B1. In other words, the alignment tolerance range B2 for subjective measurement may be used to detect whether the deviation amount Δd falls within the alignment tolerance range, and the alignment tolerance range B1 for objective measurement may be used when performing tracking control (resuming alignment) based on this detection result. This lengthens the time from when the subject's eye E and the measurement unit 7 are aligned until misalignment occurs again, thereby reducing the frequency of tracking control.

[0121] In this embodiment, the configuration has been described as an example in which the left and right eyes of the subject's eye E are in binocular vision and the ocular refractive power of each eye is measured, but this is not limiting. In this embodiment, the ocular refractive power of the right eye can be measured with the left eye obscured by an occluder or the like, and then the left eye can be measured with the right eye obscured by an occluder or the like. In other words, measurement of either the left or right eye can be performed while the other eye is in monocular vision. Even in such a case, by setting the alignment tolerance range B2 for subjective measurement to a wider tolerance range than the alignment tolerance range B1 for objective measurement of the subject's eye E, movement of the test target in subjective measurement is less noticeable, allowing for accurate measurement results.

[0122] In this embodiment, tracking control based on the alignment tolerance B1 of the objective measurement may be continuously performed from the time when the objective measurement of the subject's eye E is completed and the presentation of the fixation target is stopped until the time when the subjective measurement is started and the test target is presented. In this case, there is no need for control to switch between running and stopping the tracking control, such as stopping the tracking control when the fixation target is turned off and resuming the tracking control when the test target is turned on, and the complexity of the control is suppressed.

[0123] Furthermore, in this embodiment, tracking control based on the alignment tolerance B1 of the objective measurement may be stopped from the time when the objective measurement of the subject's eye E is completed and the presentation of the fixation target is stopped until the subjective measurement is started and the test target is presented. In this case, the movement of the measurement unit 7 is stopped when the fixation target is turned off, so even if the subject's line of sight moves significantly before the test target is presented, the measurement unit 7 will not track the subject's eye. When the subject's eye visually recognizes the test target, the line of sight returns to approximately its original position (the position when the fixation target was turned off). Therefore, when tracking control based on the alignment tolerance B1 is resumed, the movement amount of the measurement unit 7 is reduced, and as a result, the subjective measurement can be easily carried out.

[0124] Furthermore, in this embodiment, the measurement unit 7 and the concave mirror 85 may be moved relative to the subject's eye while maintaining the positional relationship between the measurement unit 7 and the concave mirror 85, and the measurement unit 7 may be moved relative to the concave mirror 85, thereby aligning the projection optical system 10a and the projection optical system 30 with the subject's eye (for details, see Japanese Patent Application No. 2021-086210). In this case, as in this embodiment, the alignment tolerance range B2 for subjective measurement may be set to a wider tolerance range than the alignment tolerance range B1 for objective measurement. [Explanation of symbols]

[0125] 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 Optometry equipment

Claims

1. An optometry apparatus for measuring optical characteristics of a subject's eye, comprising: an objective measuring optical system including a first light projecting optical system that projects a measurement light beam onto the fundus of the subject's eye, and a light receiving optical system that receives a reflected light beam of the measurement light beam reflected by the fundus by a detector, the objective measuring optical system being used to objectively measure optical characteristics of the subject's eye; a subjective measuring optical system including a second light-projecting optical system that projects a visual target light beam toward the subject's eye, and a correction optical system that is disposed in an optical path of the second light-projecting optical system and changes an optical characteristic of the visual target light beam, for subjectively measuring an optical characteristic of the subject's eye; a first control means for executing a first alignment process based on a first alignment allowable range for determining a positional deviation between the subject's eye and the objective measurement optical system; a second control means for executing a second alignment process based on a second alignment allowable range for determining a positional deviation between the subject's eye and the subjective measurement optical system; Equipped with An optometric apparatus, wherein the second alignment tolerance range is wider than the first alignment tolerance range.

2. The optometric apparatus according to claim 1, The first control means adjusts a relative positional relationship between the eye to be examined and the objective measurement optical system as the first alignment process, The optometric apparatus according to claim 1, wherein the second control means adjusts a relative positional relationship between the subject's eye and the subjective measurement optical system as the second alignment process.

3. In the optometric apparatus according to claim 1 or 2, An eye examination apparatus characterized in that it is provided with a change control means for changing the first alignment tolerance range corresponding to the objective measurement and the second alignment tolerance range corresponding to the subjective measurement when the measurement of the test eye is switched from one of objective measurement using the objective measurement optical system and subjective measurement using the subjective measurement optical system to the other.

4. In the optometric apparatus according to any one of claims 1 to 3, The eye examination device is characterized in that the change control means sets the second alignment tolerance range when the optical characteristics of the test eye are objectively measured by the objective measurement optical system while the optical characteristics of the test eye are subjectively measured by the subjective measurement optical system.

5. An objective measuring optical system having a first light projecting optical system which projects a measuring light beam onto the fundus of a test eye, and a light receiving optical system which receives a reflected light beam of the measuring light beam reflected by the fundus with a detector, the objective measuring optical system being for objectively measuring the optical characteristics of the test eye; a subjective measuring optical system including a second light-projecting optical system that projects a visual target light beam toward the subject's eye, and a correction optical system that is disposed in an optical path of the second light-projecting optical system and changes an optical characteristic of the visual target light beam, for subjectively measuring an optical characteristic of the subject's eye; Equipped with An optometry program for use in an optometry apparatus for measuring optical characteristics of the subject's eye, When executed by a processor of the optometry device, a first control step of executing a first alignment process based on a first alignment allowable range for determining a positional deviation between the subject's eye and the objective measurement optical system; a second control step of executing a second alignment process based on a second alignment allowable range for determining a positional deviation between the subject's eye and the subjective measurement optical system; Equipped with An optometry program, wherein the second alignment tolerance range is wider than the first alignment tolerance range.

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