Subjective eye examination device

Abstract

To provide a subjective optometer capable of smoothly performing temporary frame inspection.SOLUTION: A subjective optometer including: a target projection optical system for projecting a target light flux onto a subject's eye; a correction optical system disposed in an optical path of the target projection optical system and changing a correction amount of refractive power to be applied to the subject's eye; and a light guide optical system for guiding an image of the target light flux via the correction optical system to the subject's eye so as to be an optically prescribed examination distance; and subjectively measuring the optical characteristics of the subject's eye in an opened state in front of the subject's eyes, the subjective optometer includes measurement control means for changing the correction optical system into a non-correction state based on a start signal for starting temporary frame examination using a temporary frame.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a subjective ophthalmic apparatus that subjectively measures the optical characteristics of an eye to be examined.

Background Art

[0002] As a subjective ophthalmic apparatus, there is known a type of apparatus (for example, Patent Document 1) in which a lens unit (phoropter) having a correction optical system composed of a plurality of lens disks is disposed in front of the eye to be examined. Further, as a subjective ophthalmic apparatus, there has been proposed an apparatus that guides an image of an examination target to the eye to be examined through a correction optical system and subjectively measures the optical characteristics of the eye to be examined in a natural state (open state) without actually disposing the correction optical system in front of the eye to be examined (for example, Patent Document 2). Further, this apparatus has a function of automatically aligning a measurement unit having a correction optical system with the eye to be examined.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, in prescribing spectacle lenses for an eye to be examined, generally, after subjectively measuring the optical characteristics of the eye to be examined, a trial frame examination using a trial frame is performed. In the trial frame examination, the subject wears the trial frame, and the appearance of the examination target is confirmed with a test lens inserted into the trial frame.

[0005] However, it has been found that there is a disadvantage in performing a trial frame examination with an apparatus of a method in which an image of an examination target is guided to the eye to be examined through a correction optical system as in Patent Document 2.

[0006] In view of the prior art described above, the technical objective of this disclosure is to provide a subjective ophthalmography device that enables smooth preliminary frame examination. [Means for solving the problem]

[0007] A subjective optometry device provided by a typical embodiment of this disclosure comprises: a target projection optical system for projecting a target beam onto the eye under examination; a corrective optical system disposed in the optical path of the target projection optical system and changing the amount of refractive power correction applied to the eye under examination; and a light guide optical system for guiding the image of the target beam via the corrective optical system to the eye under examination at a predetermined examination distance; and is a subjective optometry device for subjectively measuring the optical characteristics of the eye under examination with the front of the eye open, and is characterized by comprising: a measurement control means for changing the corrective optical system to an uncorrected state based on a start signal for starting a temporary frame examination using a temporary frame. [Brief explanation of the drawing]

[0008] [Figure 1] This diagram shows the schematic configuration of the external appearance of a subjective optometry device. [Figure 2] This is a diagram showing the optical system arranged in the measurement section. [Figure 3] This is a schematic diagram showing the internal structure of a subjective eye examination device, viewed from the front. [Figure 4] This is a schematic diagram showing the internal structure of a subjective optometry device viewed from the side. [Figure 5] This is a schematic diagram showing the internal structure of a subjective optometry device, viewed from above. [Figure 6] This diagram shows the control system for a subjective optometry device. [Figure 7] This is an example of the display operation screen in the subjective eye refractive power measurement mode. [Figure 8] This is a diagram illustrating the temporary frame and test lens. [Figure 9] This figure shows examples of changes in the display of correction amounts during formwork inspection. [Modes for carrying out the invention]

[0009] [overview] A typical embodiment will be described below with reference to the drawings. The items classified in <> below can be used independently or in relation to each other.

[0010] The subjective optometry device in this embodiment (for example, subjective optometry device 1) comprises a target projection optical system (for example, a target projection optical system 30), a corrective optical system (for example, a corrective optical system 60), a light guide optical system (for example, a light guide optical system 80), and a measurement and control means (for example, a control unit 70). For example, the subjective optometry device may also include an automatic alignment means (for example, a first alignment index optical system 55, a second alignment index optical system 40, an observation optical system 50, and a control unit 70) and a stopping means (for example, a control unit 70) for stopping the operation of the automatic alignment means.

[0011] For example, a subjective eye examination device may include a display means (e.g., a display 6a) and a display control means (e.g., a control unit 70). For example, the display control means controls the display of the display means. Also, for example, a subjective eye examination device may include a changing means (e.g., a correction item selection field 614, a plus switch 616a, a minus switch 616b). For example, the changing means is used to change the value of the correction amount displayed on the display means.

[0012] <Visual Target Projection Optical System> For example, the target projection optical system projects the target light beam of the test target onto the eye under examination. The target projection optical system can be any configuration that projects the target light beam, and may include, for example, a configuration having a display that displays the target (e.g., display 31), a configuration having a DMD (Digital Micromirror Device), or a configuration having a target plate and a light source that illuminates the target plate from behind.

[0013] <Correction optical system> For example, the correction optical system is arranged in the optical path of the target projection optical system and changes the correction amount of the refractive power applied to the test eye. The correction optical system only needs to be able to change the optical characteristics of the target light beam in order to change the correction amount of the refractive power applied to the test eye. For example, the correction optical system may include a spherical correction optical system (e.g., drive mechanism 39) and an astigmatism correction optical system (e.g., astigmatism correction optical system 63). For example, the spherical correction optical system changes the correction amount of the spherical refractive power applied to the test eye. For example, the astigmatism correction optical system changes the correction amount of the astigmatism refractive power applied to the test eye. For example, the correction optical system may have a right-eye correction optical system and a left-eye correction optical system provided in a pair on the left and right.

[0014] <Light guiding optical system> For example, the light guiding optical system optically guides the image of the target light beam through the correction optical system to the test eye so that it becomes a predetermined inspection distance. For example, as an optical member, the light guiding optical system includes a concave mirror (e.g., concave mirror 85) for optically setting the image of the target light beam to a predetermined inspection distance. For example, the light guiding optical system only needs to be able to optically guide the image of the target light beam through the correction optical system to the test eye so that it becomes a predetermined inspection distance, and it may be a lens instead of a concave mirror. For example, with this light guiding optical system, the optical characteristics of the test eye can be voluntarily measured with the front of the test subject's eye in an open state. That is, the optical characteristics of the test eye can be measured without arranging the correction optical system in front of the test subject's eye. For example, the front of the test subject's eye is the vicinity where the spectacle lens is located when wearing glasses.

[0015] Also, when the correction optical system is composed of a right-eye correction optical system and a left-eye correction optical system provided in a pair on the left and right, the light guiding optical system may be shared by a right-eye optical path including the right-eye correction optical system and a left-eye optical path including the left-eye correction optical system.

[0016] <Measurement control means> For example, the measurement control means changes the correction optical system to an uncorrected state based on a start signal for starting a temporary frame inspection using a temporary frame. For example, changing the correction optical system to an uncorrected state may substantially mean that the correction amount of the correction optical system can be set to a state of zero. In this case, for example, it is sufficient if the spherical power and astigmatism power applied to the test eye can be set to a state of zero. In other words, the uncorrected state of the correction optical system may be a state in which correction for the test eye is not being performed. Thereby, even in a configuration in which a test target is presented through the correction optical system, the temporary frame inspection can be appropriately performed while showing the test target to the test eye. For this reason, the temporary frame inspection can be smoothly performed.

[0017] Incidentally, for example, the subjective refractometer may include a start signal input means (for example, the temporary frame inspection button 630). For example, the start signal input means is used to input a start signal for starting a temporary frame inspection using a temporary frame.

[0018] Also, for example, when the subjective refractometer includes a changing means, the measurement control means may keep the correction optical system in an uncorrected state even when the value of the correction amount is changed by the changing means. In other words, the measurement control means may maintain the uncorrected state of the correction optical system, and the value of the correction amount displayed on the display means may be made changeable by the changing means. Thereby, when the examiner changes the correction amount of the test lens set in the temporary frame, only the value of the correction amount on the display means can be changed, and the final result (prescription power) in the temporary frame inspection can be appropriately output and managed.

[0019] <Automatic alignment means> For example, the automatic alignment means detects the alignment state of the corrective optical system with respect to the eye under examination (e.g., the uncorrected eye under examination) and automatically aligns the corrective optical system with respect to the eye under examination based on the detection. For example, the automatic alignment means may include alignment detection means (e.g., an image sensor 52, a position detection element 48, and a control unit 70). For example, the alignment detection means detects the alignment state of the corrective optical system with respect to the eye under examination. For example, the alignment detection means detects the alignment state by detecting alignment indicators projected onto the eye under examination by alignment indicator projection means (e.g., a first alignment indicator optical system 55, a second alignment indicator optical system 40). Alternatively, for example, the alignment detection means may detect the alignment state based on an anterior segment image of the eye under examination captured by an imaging means (e.g., an image sensor 52).

[0020] For example, the automatic alignment means may include a driving means (e.g., a drive unit 83, a drive mechanism 82) for three-dimensionally driving the corrective optical system relative to the eye under examination, and an alignment control means (e.g., a control unit 70) for controlling the driving means. For example, the alignment control means automatically aligns the corrective optical system to a predetermined positional relationship relative to the eye under examination by controlling the driving means based on the alignment state detected by the alignment detection means.

[0021] Furthermore, the automatic alignment means may align the corrective optical system to the eye under examination even while measuring the subjective refractive power of the corrective optical system before the preliminary frame examination. That is, for example, the automatic alignment means may include automatic tracking of the alignment. For example, automatic tracking of the alignment means performs automatic alignment so that the alignment state returns to the predetermined acceptable range if the alignment state falls outside the predetermined acceptable range.

[0022] For example, if the corrective optical system has a pair of corrective optical systems for the right eye and a corrective optical system for the left eye, the automatic alignment means may be configured to automatically align the corrective optical system for the right eye and the corrective optical system for the left eye with respect to the left and right eyes being examined, respectively.

[0023] <Stopping means> For example, the stopping means stops the operation of the automatic alignment means based on the start signal for the temporary frame inspection. For example, the stopping means stops the automatic alignment means that operates when measuring the optical properties (e.g., refractive power) of the uncorrected eye of the subject based on the start signal for the temporary frame inspection. This reduces the possibility of false detection of the alignment state or malfunction of the automatic tracking due to the placement of the test lens of the temporary frame in front of the eye of the subject during the temporary frame inspection.

[0024] For example, the stopping means may include cases where the alignment operation is substantially stopped. For example, the stopping means may be configured to include either a first stopping means that directly stops the operation of the automatic alignment means, or a second stopping means that changes the alignment state detection conditions so that the automatic alignment means does not operate. For example, the first stopping means stops the operation of the automatic alignment means even if there is an alignment state detection signal. In this case, the first stopping means may include disabling (turning off) the alignment state detection signal. Alternatively, for example, the first stopping means may stop the signal that operates the drive unit of the automatic alignment means even if there is an alignment state detection signal. On the other hand, for example, the second stopping means may substantially disable the automatic alignment means by changing the alignment state detection conditions for the measurement of the optical properties of the eye under examination (e.g., refractive power) by the corrective optical system before the preliminary frame examination. Specifically, for example, the second stopping means may effectively disable the automatic alignment means by turning off (including dimming) the light sources used for alignment measurements before the temporary frame inspection (e.g., the anterior eye illumination unit 95, light source 56, light source 41), so that alignment light is not detected by the detection elements used for alignment (e.g., the image sensor 52, the position detection element 48). Alternatively, for example, the second stopping means may effectively disable the automatic alignment means by preventing the output of detection signals from the detection elements used for alignment (e.g., the image sensor 52, the position detection element 48).

[0025] Furthermore, the stopping means, for example, only needs to stop the operation of the automatic alignment means (referred to as the first automatic alignment means) when measuring the optical properties (e.g., refractive power) of the eye being examined (bare eye) before the temporary frame examination. And, for example, even if a configuration is adopted in which the system switches to a second automatic alignment means that changes the detection conditions for the alignment state in order to reduce the effect of reflected light generated when the test lens of the temporary frame is placed in front of the eye being examined, the stopping means will still have stopped the first automatic alignment means for the eye being examined in its bare eye before the temporary frame examination, so this may also be included.

[0026] <Display means, display control means> For example, the display means displays the values ​​of the correction amount measured by the corrective optical system (e.g., spherical power S, astigmatism power C, astigmatism axis angle A). For example, the display control means controls the display means so that even when the corrective optical system is changed to an uncorrected state based on the start signal for the temporary frame inspection, the values ​​of the correction amount measured by the corrective optical system immediately before the input of the start signal are displayed on the display means. This allows the examiner to know the correction value obtained in the subjective examination when setting the test lens in the temporary frame, enabling the temporary frame inspection to proceed smoothly. In addition, the examiner can output and manage the results of the temporary frame inspection.

[0027] The display control means may also display the correction amount values ​​directly in the first display area (for example, the right eye correction amount display area 618R and the left eye correction amount display area 618L) that displays the results of the subjective eye refractive power measurement by the corrective optical system. Alternatively, for example, the display control means may copy the values ​​obtained from the subjective eye refractive measurement immediately before the start signal for the preliminary frame examination is input and display them in a second display area (for example, display areas 568R and 658L) separate from the first display area. In this case, the display control means may also display the correction amount values ​​displayed in the first display area in conjunction with the corrective optical system.

[0028] <Configuration of each method> In this embodiment, at least one of the measurement control means, the stopping means, and the display control means may be combined into one. Alternatively, the measurement control means, the stopping means, and the display control means may be provided separately. Of course, these means may be composed of multiple control means.

[0029] [Examples] An embodiment of the subjective optometry device according to this embodiment will be described. Figure 1 is a diagram showing the schematic configuration of the subjective optometry device 1. In this embodiment, the subjective optometry device 1 will be described as a device that includes a subjective measurement unit for subjectively measuring the optical properties (e.g., refractive power) of the eye under examination, and an objective measurement unit for objectively measuring the optical properties (e.g., refractive power) of the eye under examination. In Figure 1, the left-right direction (horizontal direction) is described as the X direction, the up-down direction (vertical direction) as the Y direction, and the front-back direction as the Z direction, as viewed from the subject's side.

[0030] For example, the subjective optometry device 1 comprises a housing 2, a display window 3, a forehead rest 4, a chin rest 5, a controller 6, a measuring unit 7, an imaging unit 90, an anterior segment illumination unit 95, and the like.

[0031] The presentation window 3 is used to present the target to the eye being examined. The forehead rest 4, on which the subject's forehead rests, is used to maintain a constant distance between the eye being examined and the subjective optometry device 1. The chin rest 5, on which the subject's chin rests, is used to maintain a constant distance between the eye being examined and the subjective optometry device 1. Note that the chin rest 5 is not necessarily required.

[0032] The controller 6, an example of an operating unit, includes a display 6a, a switch unit 6b, and other display means. The display 6a displays various information (for example, the measurement results of the eye being examined). The display 6a has a touch panel function, and the display 6a also functions as the switch unit 6b. The switch unit 6b may be used to perform various settings (for example, inputting operation signals to various locations). Signals corresponding to operation instructions from the controller 6 are output to the control unit 70 (see Figure 6), which will be described later, by at least one of wired communication via a cable or the like, and wireless communication via infrared or the like.

[0033] The imaging unit 90 includes an imaging optical system (not shown). For example, the imaging optical system is used to image the face of the subject. For example, the imaging optical system may consist of an image sensor and a lens. The anterior segment illumination unit 95 has an infrared illumination light source (not shown) arranged inside and emits illumination light toward the left and right subject eyes for imaging the anterior segment of the subject eye by the observation optical system 50 (see Figure 2), which will be described later.

[0034] <Measurement part> The measurement unit 7 comprises a left eye measurement unit 7L and a right eye measurement unit 7R. In this embodiment, the left eye measurement unit 7L and the right eye measurement unit 7R are made of the same material. Of course, the left eye measurement unit 7L and the right eye measurement unit 7R may be made of different materials, at least in part. The measurement unit 7 has a pair of left and right target projection optical systems, a pair of left and right subjective measurement units, and a pair of left and right objective measurement units, which will be described later. The target light beam and measurement light beam from the measurement unit 7 are guided to the eye under examination via the presentation window 3.

[0035] Figure 2 shows the optical system arranged in the measurement unit 7. In Figure 2, the left eye measurement unit 7L is given as an example of the measurement unit 7. The right eye measurement unit 7R has the same configuration as the left eye measurement unit 7L and is therefore omitted. For example, the left eye measurement unit 7L includes a target projection optical system 30, a subjective measurement optical system 25, an objective measurement optical system 10, a first alignment index optical system 55, a second alignment index optical system 40, an observation optical system 50, etc.

[0036] <Visual Target Projection Optical System> The target projection optical system 30 projects the target light beam onto the eye under examination. For example, the target projection optical system 30 includes a display 31, a projection lens 33, a projection lens 34, a reflective mirror 36, an objective lens 37, a dichroic mirror 35, a dichroic mirror 29, and the like.

[0037] The display 31 shows a visual target (fixation target, test target, etc.). The visual target light beam emitted from the display 31 passes sequentially through the optical components from the projection lens 33 to the dichroic mirror 29 and is projected onto the left eye E under examination. 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. That is, the dichroic mirror 35 makes the optical axis L1 of the objective measurement optical system 10 and the optical axis L2 of the subjective measurement optical system 25 coaxial. The dichroic mirror 29 is an optical path branching member. The dichroic mirror 29 reflects the visual target light beam from the visual target projection optical system 30 and the measurement light beam from the projection optical system 10a (described later) and guides them to the eye E under examination.

[0038] In this embodiment, a display 31 is used as the light source for projecting the target light beam, but the embodiment is not limited to this. The target projection optical system 30 can be configured to project the target light beam. For example, a DMD (Digital Micromirror Device) may be used. DMDs have high reflectivity and can maintain a higher light intensity of the target light beam compared to the case where a liquid crystal display using polarization is used. Alternatively, for example, instead of a display, the embodiment may include a target plate that is switched and placed in the optical path, and a light source that illuminates the target plate from behind. For example, the target plate may be composed of a disc that is rotated by a motor or the like, and may have multiple targets such as visual acuity value targets used in measuring subjective refractive power.

[0039] <Subjective measurement optical system> The subjective measurement optical system 25 is used as part of the configuration of a subjective measurement unit that subjectively measures the optical characteristics of the eye E under examination. In this embodiment, the subjective measurement unit that measures the refractive power of the eye E under examination is given as an example of the optical characteristics of the eye E under examination. In addition to refractive power, the optical characteristics of the eye E under examination may also be contrast sensitivity, binocular vision function (e.g., amount of strabismus, stereopsis function, etc.), etc. For example, the subjective measurement optical system 25 is composed of the aforementioned target projection optical system 30 and the corrective optical system 60.

[0040] <Correction optical system> The corrective optical system 60 is positioned in the optical path of the target projection optical system 30. The corrective optical system 60 also changes the optical properties of the target light beam from the display 31. As a result, for example, the corrective optical system 60 changes the amount of refractive power (spherical refractive power, astigmatic refractive power) applied to the eye under examination. For example, the corrective optical system 60 includes an astigmatic correction optical system 63, a drive mechanism 39 used as a spherical correction optical system, and so on.

[0041] The astigmatism correction optical system 63 is used to correct the astigmatism power (cylindrical power) and astigmatism axis angle of the eye E under examination. In this embodiment, the astigmatism correction optical system 63 is positioned between the projection lens 33 and the projection lens 34. The astigmatism correction optical system 63 consists of two positive cylindrical lenses 61a and 61b with equal focal lengths. The cylindrical lenses 61a and 61b rotate independently around the optical axis L2 by the driving of the rotation mechanism 62a and the rotation mechanism 62b.

[0042] In this embodiment, the astigmatism correction optical system 63 was described using a configuration with cylindrical lenses 61a and 61b as an example, but it is not limited to this. The astigmatism correction optical system 63 can be configured to correct cylindrical power, astigmatism axis angle, etc. For example, the corrective lenses may be inserted into and removed from the optical path of the target projection optical system 30.

[0043] In this embodiment, the display 31 of the target projection optical system 30 is moved in the direction of the optical axis L2 of the target projection optical system 30 by a drive mechanism 39. For example, the drive mechanism 39 is composed of a motor and a slide mechanism. For example, during subjective measurement, the movement of the display 31 optically changes the presentation position (presentation distance) of the target to the eye being examined, and corrects the spherical refractive power of the eye being examined. In other words, in this embodiment, the movement of the display 31 constitutes a spherical power correction optical system. Then, the movement of the display 31 allows the spherical power to be measured based on the optical distance of the test target relative to the reference position.

[0044] However, the spherical power correction optical system is not limited to this. For example, the spherical power correction optical system may have a large number of optical elements, and the correction may be performed by arranging the optical elements in the optical path. Alternatively, for example, the system may be configured to move a lens placed in the optical path along the optical axis.

[0045] <Objective measurement optical system> The objective measurement optical system 10 is used as part of the configuration of the objective measurement unit that objectively measures the optical properties of the eye E under examination. In this embodiment, the objective measurement unit that measures the refractive power of the eye E under examination will be described as an example of the optical properties of the eye E under examination. For example, the objective measurement optical system 10 is composed of a projection optical system 10a and a light-receiving optical system 10b.

[0046] The projection optical system 10a projects a spot-shaped measurement indicator onto the fundus of the eye E through the center of the pupil of the eye E being examined. For example, the projection optical system 10a includes a light source 11, a relay lens 12, a hall mirror 13, a prism 15, an objective lens 14, a dichroic mirror 35, a dichroic mirror 29, and so on.

[0047] The light source 11 emits a measurement beam. The light source 11 is conjugate to the fundus of the eye under examination E. The hole portion of the hole mirror 13 is conjugate to the pupil of the eye under examination E. The prism 15 is a beam deflection member. The prism 15 is positioned away from the position conjugate to the pupil of the eye under examination E, and eccentricates the measurement beam passing through the prism 15 with respect to the optical axis L1. The prism 15 is rotationally driven by a drive unit (e.g., a motor) 23 around the optical axis L1.

[0048] The light-receiving optical system 10b extracts the retinal reflected light beam reflected from the fundus of the eye E under examination in a ring shape via the area around the pupil of the eye E under examination. For example, the light-receiving optical system 10b includes a dichroic mirror 29, a dichroic mirror 35, an objective lens 14, a prism 15, a hall mirror 13, a relay lens 16, a mirror 17, a light-receiving diaphragm 18, a collimator lens 19, a ring lens 20, an image sensor 22, and the like.

[0049] The ring lens 20 consists 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 to the pupil of the eye E under examination. The light-receiving aperture 18 and the image sensor 22 are conjugate to the fundus of the eye E under examination. The output from the image sensor 22 is input to the control unit 70.

[0050] In the above configuration, the measurement light beam emitted from the light source 11 passes sequentially through the optical components from the relay lens 12, the hall mirror 13, and the prism 15 to the dichroic mirror 29, forming a spot-shaped point light source image on the fundus of the eye E under examination. At this time, the pupil projection image (projected light beam on the pupil) in the hall mirror 13 is rapidly eccentrically rotated by the prism 15, which rotates around the optical axis. The point light source image projected onto the fundus is reflected and scattered and emitted from the eye E under examination, reflected by the dichroic mirror 29 and the dichroic mirror 35, focused by the objective lens 102, and then, via the rapidly rotating prism 15, hall mirror 13, relay lens 16, and mirror 17, is focused again at the light-receiving aperture 18, where it is formed as a ring-shaped image on the image sensor 22 by the collimator lens 19 and the ring lens 20.

[0051] In this embodiment, the prism 15 is positioned 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 under examination, and the fundus-reflected light beam reflected from the fundus of the eye E under examination also passes through the same prism 15. Therefore, subsequent optical systems are scanned in reverse as if there were no eccentricity of the projected light beam and fundus-reflected light beam (receiving light beam) above the pupil.

[0052] The optical system for measuring ocular refractive power, which is an example of the objective measurement optical system 10, is not limited to the above, as long as it can obtain ocular refractive power. For example, it may be a configuration that includes a Shack-Hartmann sensor. For further details, please refer to, for example, Japanese Patent Application Publication No. 2018-47049.

[0053] Furthermore, the light source 11 and relay lens 12 of the projection optical system 10a, and the light receiving aperture 18, collimator lens 19, ring lens 20, and image sensor 22 of the light receiving optical system 10b are all integrally movable in the optical axis direction. In this embodiment, these are moved synchronously and integrally as a drive unit 95 by a drive mechanism 39 that moves the display 31. The movement position of the drive unit 95 moved by the drive mechanism 39 is detected by a detector (not shown). Of course, these may also be configured to be driven individually.

[0054] As the drive unit 95 moves in the optical axis direction, the light source 11, the light-receiving aperture 18, and the image sensor 22 are positioned so as to be optically conjugate with respect to the fundus of the eye E being examined. Regardless of the movement of the drive unit 95, the hall mirror 13 and the ring lens 20 are positioned so as to be conjugate with the pupil of the eye E being examined at a constant magnification. Therefore, the fundus reflected light beam, which is the measurement light beam from the projection optical system 10a reflected, always enters the ring lens 20 of the light-receiving optical system 10b as a parallel light beam, and regardless of the refractive power of the eye E being examined, a ring-shaped light beam of the same size as the ring lens 20 is captured in focus on the image sensor 22.

[0055] <Alignment indicator optics> The alignment index optical system of this embodiment comprises a first alignment index optical system 55 and a second alignment index optical system 40.

[0056] The first alignment index optical system 55 comprises a light source 56 that emits near-infrared light, a collimator lens 57, and a half mirror 58. The light emitted from the light source 56 is made into a nearly parallel beam by the collimator lens 57 and reflected by the half mirror 58 so that it is coaxial with the optical axis L1 of the objective measurement optical system 10. Subsequently, the light from the light source 56 is reflected by the dichroic mirror 35 and the dichroic mirror 29 and projected onto the eye E under examination from the front. The first alignment index optical system 55 is used to detect the alignment state of the eye E under examination in the XY direction.

[0057] The second alignment indicator optical system 40 comprises a light projection optical system 40a and a detection optical system 40b. The light projection optical system 40a includes a light source 41 that emits near-infrared light and a collimator lens 42, and projects indicator light from an oblique direction toward the cornea of ​​the eye E under examination. The optical axis of the detection optical system 40b is positioned symmetrically to the optical axis of the light projection optical system 40a with respect to the optical axis L3 of the observation optical system 50. The detection optical system 40b comprises a lens 46, a focusing lens 47, and a position detection element 48. The illumination light projected by the light source 41 is reflected by the cornea of ​​the eye E under examination, forming an indicator image (corneal reflection spot), which is a virtual image of the light source 41. The light from this indicator image enters the position detection element 48 via the lens 46 and the focusing lens 47. The position of the indicator image on the position detection element 48 changes according to the position of the eye E under examination in the Z direction. The output signal from the position detection element 48 is output to the control unit 70, which then detects the alignment state of the eye E in the Z direction.

[0058] <Observation Optical System> The observation optical system (imaging optical system) 50 includes a dichroic mirror 29, an objective lens 53, an imaging lens 51, an image sensor 52, etc. The dichroic mirror 29 transmits anterior segment observation light and alignment light. The image sensor 52 has an imaging surface positioned conjugate to the anterior segment of the eye under examination E. The output from the image sensor 52 is input to the control unit 70. As a result, an anterior segment image of the eye under examination E is captured by the image sensor 52 and displayed on the display 6a.

[0059] Furthermore, the observation optical system 50 also functions as a detection optical system that detects the index image formed on the cornea of ​​the eye E being examined by the first alignment index optical system 55. Specifically, when light from the light source 56 of the first alignment index optical system 55 is reflected by the cornea of ​​the eye E being examined, an index image (corneal reflection spot), which is a virtual image of the light source 56, is formed, and this index image is received by the image sensor 52. Then, based on the output signal of the image sensor 52, the control unit 70 detects the position of the index image, thereby detecting the alignment state of the eye E being examined in the XY direction.

[0060] <Internal configuration and light guide optics of the ophthalmoscopic device> The internal configuration of the subjective optometry device 1 will now be explained. Figure 3 is a schematic diagram of the internal configuration of the subjective optometry device 1 viewed from the front. Figure 4 is a schematic diagram of the internal configuration of the subjective optometry device 1 viewed from the side. Figure 5 is a schematic diagram of the internal configuration of the subjective optometry device 1 viewed from above. Note that in Figures 4 and 5, for the sake of explanation, only the optical axis of the left eye measuring unit 7L is shown.

[0061] The subjective optometry device 1 includes a light-guiding optical system 80 that guides the image of the target light beam from the measurement unit 7 to the eye under examination. The light-guiding optical system 80 in this embodiment includes a deflection mirror 81, a reflection mirror 84, a concave mirror 85, etc., which are examples of light deflection members. The subjective optometry device 1 also includes a drive mechanism 82 and a drive unit 83 as components related to the light-guiding optical system 80. The light-guiding optical system 80 uses the concave mirror 85 of the light-guiding optical members to optically guide the image of the target light beam via the corrective optical system 60 to the eye under examination at a predetermined examination distance during subjective measurement.

[0062] The light guide optical system 80 is not limited to this configuration. For example, the light guide optical system 80 may have a configuration without a reflective mirror 84. In this case, the target light beam from the measuring unit 7 may be illuminated from an oblique direction to the optical axis L of the concave mirror 85 after passing through the deflection mirror 81. Alternatively, the light guide optical system 80 may have a configuration with a half mirror. In this case, the target light beam from the measuring unit 7 may be illuminated from an oblique direction to the optical axis L of the concave mirror 85 via the half mirror, and the reflected light beam may be guided to the eye E under examination.

[0063] The subjective optometry device 1 has a left eye drive unit 9L and a right eye drive unit 9R, and the left eye measuring unit 7L and the right eye measuring unit 7R can be moved in the X direction (horizontal direction). For example, by moving the left eye measuring unit 7L and the right eye measuring unit 7R in the X direction, the distance between the measuring unit 7 and the deflection mirror 81 described later changes, and the presentation position of the target light beam from the measuring unit 7 in the Z direction (front-to-back direction relative to the subject) is changed. As a result, the measuring unit 7 is adjusted in the Z direction so that the target light beam corrected by the corrective optical system 60 is guided to the eye E under examination, and an image of the target light beam corrected by the corrective optical system 60 is formed on the fundus of the eye E under examination.

[0064] For example, the deflection mirror 81 has a pair of right-eye deflection mirrors 81R and left-eye deflection mirrors 81L, each provided on the left and right sides. For example, the deflection mirror 81 is positioned between the measurement unit 7 and the eye under test E. In this embodiment, the deflection mirror 81R is positioned between the measurement unit 7R and the eye under test ER, and the deflection mirror 81L is positioned between the measurement unit 7L and the eye under test EL. That is, the deflection mirror 81 is positioned in the shared optical path of the objective optical system 10 and the target projection optical system 30 of the measurement unit 7. The deflection mirror 81 is also positioned in the optical path of the subjective measurement optical system 25. It is preferable that the deflection mirror 81 be positioned at the pupil conjugate position.

[0065] For example, the left eye deflection mirror 81L reflects the light beam projected from the left eye measuring 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 measuring unit 7L. For example, the right eye deflection mirror 81R reflects the light beam projected from the right eye measuring 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 measuring unit 7R. In this embodiment, a configuration in which a deflection mirror 81 is used as a deflection member that reflects the light beam projected from the measuring unit 7 to the eye under examination E and guides it is described as an example, but it is not limited to this. The deflection member only needs to be able to reflect the light beam projected from the measuring unit 7 to the eye under examination E and guide it, and may be, for example, a prism, a lens, etc.

[0066] For example, the drive mechanism 82 consists of a motor (drive unit) or the like. For example, the drive mechanism 82 has a drive mechanism 82L for driving the left eye deflection mirror 81L and a drive mechanism 82R for driving the right eye deflection mirror 81R. For example, the deflection mirror 81 rotates when driven by the drive mechanism 82. For example, the drive mechanism 82 rotates the deflection mirror 81 with respect to a rotation axis in the horizontal direction (X direction) and a rotation axis in the vertical direction (Y direction). That is, the drive mechanism 82 rotates the deflection mirror 81 in the XY direction. Note that the rotation of the deflection mirror 81 may be in either the horizontal or vertical direction.

[0067] For example, the drive unit 83 consists of a motor or the like. For example, the drive unit 83 has a drive unit 83L for driving the left eye deflection mirror 81L and a drive unit 83R for driving the right eye deflection mirror 81R. For example, the deflection mirror 81 moves in the X direction by the drive of the drive unit 83. For example, by moving the left eye deflection mirror 81L and the right eye deflection mirror 81R, the distance between the left eye deflection mirror 81L and the right eye deflection mirror 81R is changed, and the distance in the X direction between the left eye optical path and the right eye optical path can be changed to match the interpupillary distance of the eye E under examination.

[0068] Furthermore, for example, multiple deflection mirrors 81 may be provided in both the left eye optical path and the right eye optical path. For example, one configuration may involve providing two deflection mirrors in both the left eye optical path and the right eye optical path (for example, a configuration where two deflection mirrors are provided in the left eye optical path). 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 the image of the target light beam in front of the eye E under examination can be deflected, and the formation position of the image of the target light beam can be optically corrected.

[0069] For example, the concave mirror 85 is shared by the left eye measuring unit 7L and the right eye measuring 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 positioned so that it passes through both the left eye optical path including the left eye corrective optical system and the right eye optical path including the right eye corrective optical system. Of course, the concave mirror 85 does not have to be configured to be shared by the left eye optical path and the right eye optical path. For example, 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 target light beam corrected by the corrective optical system 60 to the eye under examination E so that it is optically at a predetermined examination distance. In other words, the light-guiding optical system 80, which includes the concave mirror 85, allows the area in front of the subject's eyes to be left open without having to place the corrective optical system 60 in front of the subject's eyes.

[0070] For example, the concave mirror 85 is used for both the subjective measurement unit and the objective measurement unit. For example, the target light beam projected from the subjective measurement optical system 25 is projected onto the eye under examination via the concave mirror 85. Also, for example, the measurement light projected from the objective measurement optical system 10 is projected onto the eye under examination via the concave mirror 85. Also, for example, the reflected light of the measurement light projected from the objective measurement optical system 10 is guided to the light-receiving optical system 10b of the objective measurement optical system 10 via the concave mirror 85. In this embodiment, the configuration in which the reflected light of the measurement light from the objective measurement optical system 10 is guided to the light-receiving optical system 10b of the objective measurement optical system 10 via the concave mirror 85 is given as an example, but the system is not limited to this. The reflected light of the measurement light from the objective measurement optical system 10 may be configured not to pass through the concave mirror 85.

[0071] <Optical path of the self-aware measurement unit> The optical path of the subjective measurement unit will now be explained. The subjective measurement unit guides the target light beam, which has passed through the corrective optical system 60, towards the eye under examination by a concave mirror 85, thereby forming an image of the target light beam that has passed through the corrective optical system 60 in front of the subject's eye at a predetermined examination distance. In other words, the concave mirror 85 reflects the target light beam so that it becomes a nearly parallel light beam. Therefore, the target image as seen by the subject appears to be further away than the actual distance from the eye under examination E to the display 31. That is, by using the concave mirror 85, the target image can be presented to the subject so that the image of the target light beam is visible at a predetermined examination distance.

[0072] Let's explain in more detail. In the following explanation, we will use the left eye optical path as an example. The right eye optical path has the same configuration as the left eye optical path. For example, in the left eye subjective measurement means, the target light beam projected from the display 13 of the left eye measurement means 7L enters the astigmatism correction optical system 63 via the projection lens 33. The target light beam that has passed through the astigmatism correction optical system 63 is projected from the left eye measurement means 7L toward the left eye deflection mirror 81L via the reflective mirror 36, dichroic mirror 35, and dichroic mirror 29. The target light beam emitted from the left eye measurement means 7L and reflected by the left eye deflection mirror 81 is reflected toward the concave mirror 85 by the reflective mirror 84. The target light beam reflected by the concave mirror reaches the left eye EL.

[0073] As a result, a target image corrected by the corrective optical system 60 is formed on the fundus of the left eye EL, based on the position where the subject's left eye EL is fitted with glasses (for example, about 12 mm from the corneal apex). Therefore, it is equivalent to the astigmatism correcting optical system 63 being positioned in front of the eye, and the spherical power adjustment by the spherical power correcting optical system (in this embodiment, the driving mechanism 39) being performed in front of the eye, allowing the subject to sight the target image in a natural, open state via the concave mirror 85. The optical path for the right eye is configured similarly to the optical path for the left eye, and a target image corrected by a pair of corrective optical systems 60 is formed on the fundus of both eyes, based on the position where the left and right eyes E are fitted with glasses (for example, about 12 mm from the corneal apex). In this way, the subject looks directly at the target in a natural state of vision and responds to the examiner, correcting with the corrective optical system 60 until the test target appears properly, and the optical characteristics of the eye are subjectively measured based on the corrected value.

[0074] <Optical path of the objective measurement unit> The optical path of the objective measurement unit will be explained below. In the following explanation, the optical path for the left eye will be used as an example, but the optical path for the right eye has the same configuration as the optical path for the left eye. For example, in the objective measurement unit for the left eye, the measurement light emitted from the light source 11 of the projection optical system 10a in the objective measurement optical system 10 passes through the relay lens 12 and the dichroic mirror 29, and is projected from the left eye measurement unit 7L toward the left eye deflection mirror 81L. The measurement light emitted from the left eye measurement unit 7L and reflected by the left eye deflection mirror 81 is reflected by the reflection mirror 84 toward the concave mirror 85. The measurement light reflected by the concave mirror reaches the left eye EL, forming a spot-shaped point light source image on the fundus of the left eye EL. At this time, the pupil projection image (projected light beam on the pupil) of the hole portion of the hole mirror 13 is rapidly eccentrically rotated by the prism 15 rotating around the optical axis.

[0075] Light from a point light source formed on the fundus of the left eye EL is reflected and scattered, exiting the eye E under test, and is focused by the objective lens 14 via the optical path through which the measurement light passed, reaching the prism 15, hall mirror 13, relay lens 16, and mirror 17. The light reflected by the mirror 17 is focused again at the aperture of the light receiving diaphragm 18, made into a nearly parallel beam (in the case of an emmetropic eye) by the collimator lens 19, extracted as a ring-shaped beam by the ring lens 20, and received as a ring image by the image sensor 22. By analyzing the received ring image, the optical properties of the eye E under test can be objectively measured.

[0076] <Department Head> Figure 6 shows the control system of the subjective optometry device 1. For example, the control unit 70 is connected to various electrical elements such as the imaging unit 90, the anterior segment illumination unit 95, the display 6a and switch unit 6b of the controller 6, the light source 11, image sensor 22, display 31, image sensor 52, drive mechanism 39, rotation mechanism 62a, rotation mechanism 62b, the light source 56 of the first alignment index optical system 55, the light source 41 and position detection element 48 of the second alignment index optical system 40, the drive mechanism 82 and drive unit 83 of the light guide optical system 80. The control unit 70 is also connected to a memory 75 (e.g., non-volatile memory), which is an example of a storage means, and a printer 77. For example, the memory 75 is a non-transient storage medium that can retain its contents even if the power supply is cut off. For example, a hard disk drive, flash ROM, USB memory, etc. can be used as the memory 75. The printer 77 prints out the measurement results.

[0077] For example, the control unit 70 includes a CPU (processor), RAM, ROM, etc. For example, the CPU is responsible for controlling each component of the subjective optometry device 1. For example, RAM temporarily stores various types of information. For example, ROM stores various programs, visual targets, initial values, etc., for controlling the operation of the subjective optometry device 1. The control unit 70 may be composed of multiple control units (i.e., multiple processors).

[0078] Furthermore, the control unit 70 also functions as a display control means for controlling the display on display 6a and the display on display 31. In addition, the control unit 70 also functions as a measurement control means for controlling the drive system (drive mechanism 39, rotation mechanism 62a, rotation mechanism 62b) of the corrective optical system 60. Furthermore, the control unit 70 also functions as an alignment control means for controlling the drive mechanism 82 and drive unit 83 of the light guide optical system 80.

[0079] <Operation> The operation of the subjective optometry device 1, which has the above configuration, will now be explained. The subject places their forehead on the forehead rest 4 and observes the presentation window 3. Once the subject is ready for examination, the examiner operates the touch panel (or switch unit 6b) of the display 6a of the controller 6 to input a selection signal for a target (fixation target) to fixate on the eye being examined E. The control unit 70 displays the same target based on the target selection signal on the displays 31 provided in the left eye measurement unit 7L and the right eye measurement unit 7R, respectively. Although a target is presented to each of the left and right eyes being examined E (left eye EL and right eye ER), the subject recognizes it as a single target for both eyes because the same target is presented. In the case of monocular measurement, the target is displayed only on the display 31 on the side of the eye being measured.

[0080] <Alignment of the measurement unit with respect to the eye being examined> Next, the examiner inputs a start signal via the touch panel (or switch unit 6b) of the display 6a to align the left eye measuring unit 7L and the right eye measuring unit 7R to the subject's left eye EL and right eye ER, respectively. Indices from the first alignment indicator optical system 55 and the second alignment indicator optical system 40 are projected onto the left eye EL and right eye ER, respectively. This activates an automatic alignment means that positions the measuring unit 7, including the corrective optical system 60, etc., in a predetermined three-dimensional position relative to the subject's eye E. The operation of the automatic alignment means will be described below.

[0081] The indicator from the first alignment indicator optical system 55 is received by the image sensor 52, and the alignment state of the measurement unit 7 in the XY direction is detected based on the output signal from the image sensor 52. Based on the detection result of the alignment state of the measurement unit 7 in the XY direction, the control unit 70 controls the driving of the drive mechanism 82 (82L, 82R) and the drive unit 83 (83L, 83R) to automatically adjust the alignment in the XY direction. Specifically, for example, the alignment light from the first alignment indicator optical system 55 is projected from the front of the eye E under examination, and as this light is reflected by the cornea, an indicator showing the reflected bright spot at the center of the cornea of ​​the eye under examination is imaged on the image sensor 52. The drive mechanism 82 and the drive unit 83 are controlled to adjust the alignment of the optical axis of the measurement unit 7 (correction optical system 60 of the objective measurement optical system 10 and subjective measurement optical system 25) in the XY direction, so that the index formed in the center of the cornea falls within a predetermined tolerance range with respect to a reference position in the XY direction on the image sensor 52.

[0082] The XY alignment adjustment may be performed based on the detection result of the pupil center of the eye being imaged by the image sensor 52. The anterior segment of the eye, including the pupil, is illuminated by the anterior segment illumination unit 95 and imaged by the image sensor 52.

[0083] Furthermore, the indicator from the second alignment indicator optical system 40 is received by the position detection element 48, and the alignment state of the measurement unit 7 in the Z direction is detected based on the output signal of the position detection element 48. Based on the detection result of the alignment state of the measurement unit 7 in the Z direction, the control unit 70 controls the driving of the drive unit 9 (9L, 9R) and automatically adjusts the alignment in the Z direction. Specifically, for example, when the indicator from the second alignment indicator optical system 40 is projected from an oblique direction to the eye E under examination, an indicator showing a bright spot of corneal reflection is detected on the position detection element 48. The position of the indicator on the position detection element 48 changes according to the positional relationship between the eye under examination and the measurement unit 7 in the Z direction. The driving of the drive unit 9 is controlled so that the indicator falls within a predetermined tolerance range with respect to the reference position in the Z direction on the position detection element 48, thereby adjusting the alignment of the measurement unit 7 (corrective optical system 60 of the objective measurement optical system 10 and subjective measurement optical system 25) in the Z direction.

[0084] In this embodiment, the configuration described as adjusting the alignment in the XYZ direction by driving the deflection mirror 81 with the drive mechanism 82 and the drive unit 83, and moving the measurement unit 7 with the drive unit 9L and the drive unit 9R, is not limited to this. Any configuration that can adjust the positional relationship between the eye under examination and the subjective measurement unit and the objective measurement unit is acceptable. That is, any configuration that can adjust the XYZ direction so that the image of the visual target corrected by the corrective optical system 60 is formed on the fundus of the eye under examination is acceptable. For example, a configuration may be provided in which the housing 2 on which the measurement unit 7 is arranged can be moved in the XYZ direction relative to the chin rest 6, and the housing 2 can be moved. In this case, it is preferable to provide a configuration in which the deflection mirror 81L for the left eye and the deflection mirror 81R for the right eye can be moved in the X direction, respectively. This makes it possible to adjust the left-right direction of the optical axes of the measurement unit 7L and the measurement unit 7R in accordance with the interpupillary distance of the subject. Alternatively, for example, a configuration may be provided in which the adjustment in the XYZ direction can be performed by the deflection mirror 81 alone. In this case, for example, the deflection mirror 81 is rotated and moves in the Z direction so that the distance between it and the measuring unit 7 is changed.

[0085] Furthermore, even after completing the adjustment of the alignment in the XYZ directions, the control unit 70, based on the detection result of the alignment state of the positional relationship between the eye under examination and the measurement unit 7, controls the driving of the drive unit 9, drive mechanism 82, and drive unit 83 so that the alignment state returns to the predetermined acceptable range if the alignment state falls outside the predetermined acceptable range. In other words, automatic alignment tracking is performed.

[0086] <Objective eye refractive power measurement> Once alignment with the eye E is complete, the control unit 70 issues a trigger signal to start objective refractive power measurement (objective measurement) based on the alignment completion signal. When the trigger signal to start objective measurement is issued, the control unit 70 emits a measurement beam from the objective measurement optical system 10. In this case, each measurement beam is reflected by the concave mirror 85 via the deflection mirrors 81R and 81L, and then projected onto the fundus of the eye being examined. The measurement light reflected from the fundus is then captured by the image sensors 22 of the left and right measurement units 7 via the concave mirror 85 and the deflection mirrors 81R and 81L, and a measurement image is captured.

[0087] For example, in the measurement of objective refractive power, a preliminary measurement of the eye's refractive power is performed first, and based on the results of the preliminary measurement, the display 31 may be moved in the direction of the optical axis L2, thereby creating a haze over the eye E being examined. Subsequently, the main measurement of the eye's refractive power may be performed on the haze-covered eye. In the main measurement, the measurement image is captured by the image sensor 22, and the output signal from the image sensor 22 is stored in the memory 75 as image data (measurement image). Then, the control unit 70 performs image analysis on the ring image stored in the memory 75 to determine the refractive power values ​​in each meridian direction. The control unit 70 then applies predetermined processing to this refractive power to obtain the objective refractive power (objective value) of the eye's S (spherical power), C (astigmatism power), and A (astigmatism axis angle) when the eye is used for distance vision. The obtained objective value when the eye is used for distance vision is stored in the memory 75.

[0088] The objective refractive power of the eye being examined may be measured simultaneously in both eyes, or separately in each eye. The objective refractive power may be measured multiple times (for example, three times) in each eye, and a representative value may be used in the subsequent subjective refractive power measurement.

[0089] <Subjective measurement of refractive power> After the objective eye refractive power measurement is completed, the examiner operates the controller 6 (in this embodiment, the display 6a also functions as the control unit) and selects the subjective eye refractive power measurement mode, making the subjective eye refractive power measurement possible.

[0090] Figure 7 shows an example of the operation screen 600 of the display 6a in the subjective refractive power measurement mode. The examiner operates the operation screen 600 to select the visual target to be presented to the eye under examination (the test visual target displayed on the display 31), and while obtaining the subject's response regarding how well they can see the visual target, changes the values ​​of the correction amounts (spherical power S, astigmatism power C, astigmatism axis angle A, etc.) of the left and right corrective optical systems 60 to obtain a measurement of the subjective refractive power.

[0091] On the measurement screen 600, a right eye button 610R, a left eye button 610L, and a binocular selection button 610C are provided at the top center of the screen for selecting the measurement eye. The window display 612R to the right of the right eye button 610R and the window display 61L to the left of the left eye button 610L indicate the occluded / open state of the measurement eye, respectively. A white circle is displayed when the measurement eye is open (the test target is presented), and a black circle is displayed when the measurement eye is occluded (the test target is not presented). In the example in Figure 7, the right eye is selected using the right eye button 610R, so the right eye is in the open state and the left eye is in the occluded state.

[0092] In the center of the screen is a correction item selection field 614 for selecting the correction amount (also called the correction power) of the corrective optical system 60. When "S" is selected, the correction amount of spherical power S can be changed; when "C" is selected, the correction amount of astigmatism power C can be changed; and when "A" is selected, the correction amount of astigmatism axis angle A can be changed. Each correction amount can be increased or decreased in predetermined steps by pressing the plus switch 616a and the minus switch 616b. For example, spherical power S and astigmatism power C can be increased or decreased by 0.25 D (diopters), and astigmatism axis angle A can be increased or decreased by 5 degrees (or 1 degree).

[0093] The right eye correction amount display field 618R, located to the left of the correction item selection field 614, displays the correction amount for the right eye, and the left eye correction amount display field 618L, located to the right of the correction item selection field 614, displays the correction amount for the left eye. Depending on the selection of each correction item, the displayed values ​​in the right eye correction amount display field 618R and the left eye correction amount display field 618L are inverted. In the example in Figure 7, spherical power S is selected as the correction item.

[0094] The right target display section 622R in the lower left of the right eye correction amount display section 618R, and the left target display section 622L in the lower right of the left eye correction amount display section 618L, respectively, display the test targets presented on the display 31 of the target projection optical system 30. In the example in Figure 7, a visual acuity value target is displayed. The test targets presented on the display 31 can be selected from the targets displayed in the target selection section 624. For example, the targets selectable in the target selection section 624 include not only visual acuity value targets, but also red and green targets, point cloud targets used in astigmatism tests, etc. When a visual acuity value target is selected, visual acuity value change buttons 626a and 626b are provided in the lower right of the screen to change the visual acuity value (the test target with a size corresponding to the visual acuity value).

[0095] Additionally, a temporary frame inspection button 630 is provided in the center of the bottom of the screen to switch to temporary frame inspection mode.

[0096] Let's return to the explanation of subjective eye refractive power measurement. For example, at the start of subjective eye refractive power measurement, the control unit 70 drives and initializes the left and right corrective optical systems 60 based on the objective refractive powers (spherical power S, astigmatism power C, astigmatism axis angle A) of the left and right eyes obtained from objective eye refractive power measurement. Then, the correction amounts set by the left and right corrective optical systems 60 are displayed in the right eye correction amount display field 618R and the left eye correction amount display field 618L on the operation screen 600. Subjective eye refractive power measurement, for example, involves determining the full correction power of the right eye and the full correction power of the left eye, and then performing a measurement to determine the power as a binocular balance.

[0097] When the right eye button 610R on the operation screen 600 is selected to first measure the full corrected power of the right eye, the optical path of the corrective optical system 60 on the left eye side of the non-measured eye is occluded. For example, occlusion of the non-measured eye side can be achieved by turning off the display 31 that displays the visual target, or by displaying only the background of the visual target on the screen of the display 31 on the non-measured eye side, without displaying the test visual target.

[0098] In measuring full corrected power, for example, the examiner selects a red-green target as the test target. The purpose of the red-green target at this stage is to place the circle of least confusion on the retina for the subsequent astigmatism measurement, and the examiner changes (adjusts) the spherical power S so that the red-background target and the green-background target appear equally clear (or the green-background target appears slightly clearer).

[0099] Next, the examiner selects a point cloud target to measure the astigmatism axis angle A and adjusts the astigmatism axis angle A so that the point cloud target appears clearer. Subsequently, the examiner adjusts the astigmatism power C, keeping the point cloud target as the test target, so that the point cloud target appears clearer. Next, the examiner selects the red and green targets again as the test targets and adjusts the spherical power S so that the red background target and the green background target appear to be of similar quality (or the green background target appears slightly better). The measurement using the red and green targets after the astigmatism measurement is performed to prevent overcorrection.

[0100] Next, the examiner selects a visual acuity target (for example, a target with a visual acuity of 1.0) and measures (adjusts) the spherical power S that is most positive in order to obtain the best visual acuity. The examiner also changes the visual acuity value of the target using the visual acuity change buttons 626a and 626b and confirms the best visual acuity.

[0101] Once the fully corrected prescription for the subject's right eye is obtained, the examiner similarly measures the fully corrected prescription for the left eye. Subsequently, the examiner performs a binocular balance test and adjusts the spherical power S and astigmatism power C so that the visual acuity target appears approximately equal in the subject's right eye and left eye.

[0102] <Temporary frame inspection> Once the subjective refractive power measurement is complete, the procedure moves to a temporary frame test using a temporary frame. The examiner selects the temporary frame test mode by pressing the temporary frame test button 630 on the measurement screen 600. Pressing the temporary frame test button 630 inputs a start signal to begin the temporary frame test.

[0103] When set to the preliminary frame examination mode, the control unit 70 changes the left and right corrective optical systems 60 to an uncorrected state based on the input preliminary frame examination start signal. That is, the control unit 70 drives the corrective optical systems 60 so that the spherical power S and astigmatism power C become zero. In other words, the control unit 70 puts the eye under examination in a state where no correction is performed by the corrective optical systems 60. Then, the eye under examination is presented with a test target at a predetermined test distance (distance vision distance) without any correction by the corrective optical systems 60.

[0104] Furthermore, the control unit 70 changes the left and right corrective optical systems 60 to an uncorrected state based on the start signal for the temporary frame inspection. However, the display of the correction amount (spherical power S, astigmatism power C, and astigmatism axis angle A) in the right eye correction amount display field 618R and the left eye correction amount display field 618L on the measurement screen 600 remains at the value immediately before the start signal for the temporary frame inspection is input. In other words, the final correction amount value obtained from the subjective eye refractive power measurement remains displayed. This allows the examiner to know the correction amount value obtained from the subjective eye refractive power measurement when setting the test lens TL in the lens frame of the temporary frame (temporary frame glasses) TF shown in Figure 8, and to set the test lens TL accordingly. This enables the temporary frame inspection to be performed smoothly. In other words, when performing a preliminary frame examination by presenting the test target, which is in a state of correction via the corrective optical system 60, to the eye under examination, if the correction amount of the corrective optical system 60 and the display of the correction amount on the measurement screen 600 (correction amount display section 618R, 618L) remain linked, and the corrective optical system 60 is set to an uncorrected state, the correction amount on the measurement screen 600 will also become zero. In this case, the value of the correction amount obtained from the subjective eye refraction measurement cannot be known from the display on the display 6a, and it becomes necessary to record the correction amount from the subjective eye refraction measurement, for example, by taking notes. This can be inconvenient when performing a preliminary frame examination. This inconvenience is mitigated in this disclosure.

[0105] Furthermore, the examiner may be notified by a display on the measurement screen 600 that the measurement state of the subjective optometry device 1 has been set to the temporary frame examination mode when the temporary frame examination button 630 is pressed. For example, the display color of the temporary frame examination button 630 can be changed in temporary frame examination mode. This allows the examiner to recognize that the measurement state has entered temporary frame examination mode and to understand that even if they perform an operation to change the amount of correction, the corrective optical system 60 remains in the uncorrected state and does not change.

[0106] The examiner determines the correction amount (refractive power) of the test lens while looking at the value obtained from the subjective eye refraction measurement, and sets the test lens TL in the temporary frame TF. The subject is then asked to wear the temporary frame TF. The examiner then displays a visual acuity target on the display 31 and performs a temporary frame test to check how well the target is visible to the subject while wearing the temporary frame TF.

[0107] Here, when the control unit 70 receives a signal to start the preliminary frame examination, it stops the automatic alignment operation of the measurement unit 7 (corrective optical system 60) to the eye under examination based on that signal (including cases where it is substantially stopped). For example, even if the control unit 70 receives a detection signal from the image sensor 52 that detects the index of the first alignment index optical system 55 and a detection signal from the position detection element 48 that detects the index of the second alignment index optical system 40, it directly stops the operation of the automatic alignment by stopping the drive of the drive mechanism 82 and the drive unit 83 (turning it OFF). In this case, it may also include disabling (turning OFF) the alignment status detection signal. Alternatively, the control unit 70 may stop (not output) the signal that operates the drive mechanism 82 and the drive unit 83 even if there is an alignment status detection signal. Or, the control unit 70 may change the alignment detection conditions when aligning the measurement unit 7 (corrective optical system 60) to the eye under examination during measurement, so that the automatic alignment does not operate. In this case, for example, the control unit 70 turns off (including dimming) the light sources used for alignment (anterior eye illumination unit 95, light source 56, and light source 41) so that alignment light is not detected by the detection elements used for alignment (image sensor 52, position detection element 48), thereby preventing the drive mechanism 82 and drive unit 83 from operating for the alignment operation. Alternatively, for example, the control unit 70 prevents the output of detection signals from the detection elements used for alignment (from image sensor 52 and position detection element 48), thereby preventing the drive mechanism 82 and drive unit 83 from operating for the alignment operation. In addition, any control that changes the alignment detection conditions to prevent automatic alignment from operating is acceptable.

[0108] Furthermore, even if the automatic alignment operation stops during the preliminary frame examination, the alignment adjustment for the eye has already been completed by the subjective refractive power measurement immediately prior to that point. Therefore, if that state is maintained, the subject can see the examination target through the corrective optical system 60.

[0109] In this way, during the temporary frame examination, the automatic alignment operation during refractive power measurement by the corrective optical system 60 is stopped, which reduces the possibility of misdetection of the alignment state or malfunction of automatic tracking due to the position of the test lens TL of the temporary frame TF in front of the subject's eyes, and allows the temporary frame examination to be performed smoothly. In other words, when the test lens TL of the temporary frame TF is positioned in front of the subject's eyes, the alignment light from the light source (anterior segment illumination unit 95, light source 56 and light source 41) used for alignment during refractive power measurement by the corrective optical system 60 is reflected by the test lens TL. This reflected light may not be properly detected by the detection element (image sensor 52, position detection element 48), and may be detected as an indicator of an incorrect position or result in an alignment error. In contrast, by stopping the automatic alignment operation as described above, the inconveniences in performing the temporary frame examination can be avoided.

[0110] When the examiner changes the amount of correction (for example, increasing or decreasing the spherical power S, increasing or decreasing the astigmatism power C, etc.) during the visual examination in the temporary frame examination, they use the correction amount increase / decrease switches 616a and 616b to change the value of the correction amount displayed on the operation screen 600 (display in the right eye correction amount display field 618R and the left eye correction amount display field 618L), similar to the examination in conventional phoropters (see, for example, Japanese Patent Publication No. 5-176893). In this case as well, in the temporary frame examination mode, the control unit 70 keeps the corrective optical system 60 in an uncorrected state. In other words, the control unit 70 maintains the uncorrected state of the corrective optical system 60. As a result, there is no change in the presentation of the examination target via the corrective optical system 60, and the change in the amount of correction is performed only in the temporary frame TF, so the temporary frame examination can be performed smoothly.

[0111] Furthermore, the examiner can operate the controller 6 with the same ease of use as a conventional phoropter. That is, in a conventional framing examination using a phoropter, the phoropter is moved out of the subject's sight, and the examination is performed while presenting the test target through the test lens TL set in the framing TF. In this case, the correction amount value of the controller is changed according to the correction amount of the test lens TL set in the framing TF, and the correction amount of the phoropter's corrective optical system is also changed in conjunction with this, but since the phoropter is moved out of the subject's sight, it does not affect the framing examination. In the subjective optometry device 1 of this disclosure, the corrective optical system 60 remains in an uncorrected state when in framing examination mode, so even if the displayed value of the correction amount is changed, it does not affect the framing examination.

[0112] Once the final correction amount is determined during the preliminary frame examination, pressing the print switch 640 prints the correction amount value for the eyeglass lens prescription from the printer 77. The results of the subjective refractive power measurement are also recorded in memory 75, associated with the subject's ID number. This ensures proper management of the subject's test results, similar to the use of conventional phoropters. When the preliminary frame examination is complete and the preliminary frame examination button 630 is pressed again, the system exits preliminary frame examination mode and returns to the original normal examination mode. At this time, the display color of the preliminary frame examination button 630 changes back to its original color. This change in display notifies the examiner that the system has returned to normal examination mode.

[0113] <Example of transformation> While typical embodiments of this disclosure have been described above, this disclosure is not limited to the embodiments shown herein, and various modifications are possible.

[0114] For example, in the above embodiment, a configuration in which an astigmatism correction optical system 63 and a spherical correction optical system (for example, a driving means 39) are separately provided as the corrective optical system was described as an example, but it is not limited to this. For example, the corrective optical system can be configured to change the spherical power, astigmatism power, and astigmatism axis angle. For example, the corrective optical system may be an optical system that modulates the wavefront. Also, for example, the corrective optical system may be configured in which a large number of optical elements (spherical lenses, cylindrical lenses, dispersion prisms, etc.) are arranged on the same circumference of a lens disk. In this case, the optical elements desired by the examiner are positioned on the optical axis L2 by controlling the rotation of the lens disk by a driving unit (actuator, etc.).

[0115] Furthermore, the optical elements (e.g., cylindrical lenses, cross-cylinder lenses, rotary prisms, etc.) positioned on the optical axis L2 may be rotated by a drive unit so that the optical elements are positioned on the optical axis L2 at a rotation angle desired by the examiner. Switching of the optical elements positioned on the optical axis L2 may be performed by operating an input means (operating means) such as a display 6a.

[0116] For example, a lens disk may consist of one lens disk or multiple lens disks. When multiple lens disks are arranged, a drive unit corresponding to each lens disk is provided. For example, in a group of lens disks, each lens disk may have an aperture (or 0D lens) and multiple optical elements. Typical types of lens disks include a spherical lens disk having multiple spherical lenses of different powers, a cylindrical lens disk having multiple cylindrical lenses of different powers, and an auxiliary lens disk having multiple types of auxiliary lenses. The auxiliary lens disk may have at least one of the following: a red filter / green filter, a prism, a cross-cylinder lens, a polarizer, a Maddox lens, or an auto-cross-cylinder lens. Furthermore, the cylindrical lens may be rotatable around the optical axis L2 by a drive unit, and the rotary prism and cross-cylinder lens may be rotatable around their respective optical axes by a drive unit.

[0117] Furthermore, regarding the display of the correction amount on the measurement screen 600 during the temporary frame inspection, in the above embodiment, when the start signal for starting the temporary frame inspection is input, the correction amount displayed in the right eye correction amount display field 618R and the left eye correction amount display field 618L remains at the value immediately before the start signal for the temporary frame inspection is input, but this is not limited to this. It is sufficient that the value immediately before the start signal for the temporary frame inspection is input is displayed on the display 6a. For example, as shown in Figure 9, the displays in the right eye correction amount display field 618R and the left eye correction amount display field 618L are displayed in conjunction with the correction amount of the corrective optical system 60, but the value obtained from the subjective eye refraction measurement immediately before the start signal for the temporary frame inspection is input may be copied and displayed in display fields 568R and 658L, which are separate display areas from the right eye correction amount display field 618R and the left eye correction amount display field 618L. Then, if the correction amount of the test lens TL is changed during the temporary frame inspection, and the plus switch 616a and minus switch 616b are operated, the values ​​in display fields 568R and 658L will be changed.

[0118] Furthermore, in the above explanation, when the system switches to the temporary frame inspection mode, even if the plus switch 616a and minus switch 616b for fine-tuning the correction amount are operated, the corrective optical system 60 remains in the uncorrected state. However, the following is also possible. That is, when the signal to start the temporary frame inspection is input, the corrective optical system 60 is changed to the uncorrected state. However, when the plus switch 616a and minus switch 616b are operated in the temporary frame inspection mode, the correction amount of the corrective optical system 60 may be changed by the amount of increase or decrease. For example, if the spherical power S is changed to the positive side by 0.25D by the plus switch 616a, the correction amount of the spherical power of the corrective optical system 60 is changed from 0D to plus 0.25D. Next, if the spherical power S is changed to the negative side by 0.25D by the minus switch 616b, the correction amount of the spherical power of the corrective optical system 60 is returned to 0D. This allows for easy comparison of the subject's vision before and after a change in the correction amount, without having to replace the test lens TL set in the temporary frame TF, simply by operating the subjective optometry device 1. [Explanation of Symbols]

[0119] 1. Subjective eye examination device 6a display 30 Target projection optical system 40. Second alignment indicator optical system 50 Observation Optical System 55. First alignment indicator optical system 60 Corrective optical system 70 Control Unit 80 Light guiding optical system 600 Measurement screen 614 Orthodontic item selection field 614 616a Plus switch 616b Negative switch 618R Right eye correction amount display field 618L Left eye correction amount display field 630 Temporary frame inspection button

Claims

1. A target projection optical system for projecting a target light beam onto the eye under examination, A corrective optical system is placed in the optical path of the aforementioned target projection optical system and changes the amount of refractive power corrected to the eye under examination, A light-guiding optical system that guides the image of the target light beam via the corrective optical system to the eye under examination so that it is optically at a predetermined examination distance, A subjective ophthalmography device having a function that allows the subject to subjectively measure the optical properties of the eye under examination with the viewer's eyes open, A measurement control means that changes the corrective optical system to an uncorrected state based on a start signal for initiating a temporary frame inspection using a temporary frame, A subjective optometry device characterized by being equipped with the following features.

2. In the subjective eye examination device of claim 1, An automatic alignment means that detects the alignment state of the corrective optical system with respect to the eye under examination and automatically aligns the corrective optical system with respect to the eye under examination based on the detection, A stop means for stopping the operation of the automatic alignment means based on the start signal, A subjective optometry device characterized by being equipped with the following features.

3. In the subjective eye examination device of claim 2, The subjective optometry device is characterized in that the stopping means includes either a first stopping means for directly stopping the operation of the automatic alignment means, or a second stopping means for changing the detection conditions for the alignment state during measurement, in such a way that the automatic alignment means does not operate, with respect to the detection conditions for the alignment state during measurement, in which the optical characteristics of the eye to be examined are measured by the corrective optical system.

4. In any of the subjective ophthalmoscopic devices of claims 1 to 3, A display means for displaying the value of the correction amount measured by the correction optical system, The system comprises a display control means for controlling the display means, The display control means is characterized in that, even when the corrective optical system is changed to an uncorrected state based on the start signal of the temporary frame inspection, it displays the value of the amount of correction measured by the corrective optical system immediately before the input of the start signal on the display means.

5. In the subjective ophthalmoscopic device of claim 4, The display means includes a changing means for changing the value of the correction amount displayed, The measurement control means is characterized in that it maintains the uncorrected state of the corrective optical system even when the value of the correction amount is changed by the modification means.

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