ophthalmic devices

Abstract

To provide an ophthalmologic apparatus capable of properly releasing adjustment of a subject eye.SOLUTION: The apparatus comprises: an eye refractive power measurement system 43 which objectively measures the eye characteristics of a subject eye E; an optotype projection system 42 which presents a fixation target at a predetermined presentation position to the subject eye E and applies mist to the subject eye E; and a control unit 40 which controls the eye refractive power measurement system 43 and the optotype projection system 42. The control unit 40 objectively measures the eye characteristics in time series while changing the presentation position of the fixation target in a direction of increasing a mist amount.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to an ophthalmic device. [Background technology]

[0002] Conventionally, an ophthalmic device is known that continuously measures the spherical power of the subject's eye while presenting a fixation target to the subject's eye at a predetermined presentation position and fogging it to remove accommodation from the subject's eye, and determines whether accommodation from the subject's eye has been removed based on the measured spherical power (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 11-346997 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in children and subjects who spend most of their time near-vision, the crystalline lens may be tense even when viewing distances, resulting in a state of so-called pseudomyopia. Furthermore, since accommodation of the subject's eye is difficult to release in a pseudomyopic state, even if the change in spherical power converges when a fixation target is presented at a uniform presentation position, the subject's eye may not actually be fully released from accommodation (pseudomyopia may not be alleviated). In other words, the presentation position of the fixation target, which is required to create the fogging required to release accommodation of the subject's eye, differs from person to person, making it difficult to properly release accommodation of the subject's eye.

[0005] The present invention has been made in view of the above-mentioned problems, and has as its object to provide an ophthalmic apparatus that can appropriately release the accommodation of the subject's eye. [Means for solving the problem]

[0006] In order to achieve the above object, the ophthalmologic apparatus of the present invention comprises an objective measurement optical system that objectively measures ocular characteristics of an eye to be examined, a target projection system that presents a fixation target at a predetermined presentation position to the eye to be examined and fogging the eye to be examined, and a control unit that controls the objective measurement optical system and the target projection system, and the control unit objectively measures the ocular characteristics in time series while presenting the fixation target by changing the presentation position of the fixation target in a direction that increases the amount of fogging. Based on the objective measurement results of the eye characteristics measured in time series, a strain tendency of the subject's eye, which indicates a tendency of each subject's eye to fogging, is estimated, and the estimated strain tendency is notified. do. [Effects of the Invention]

[0007] In the ophthalmologic apparatus of the present invention configured as described above, the accommodation of the subject's eye can be appropriately released. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a perspective view showing the overall configuration of an ophthalmologic apparatus according to a first embodiment. [Figure 2] FIG. 2 is a diagram showing a detailed configuration of a left measurement optical system of the ophthalmologic apparatus of the first embodiment. [Figure 3] 10 is a flowchart showing a flow when an objective test or a subjective test is performed by the control unit of the first embodiment. [Figure 4] 4 is a flowchart showing the flow of fogging control performed by the control unit of the first embodiment. [Figure 5] 1 is a first example of a graph showing the relationship between the amount of fogging and the objective measurement results of eye characteristics. [Figure 6] 10 is a second example of a graph showing the relationship between the amount of fogging and the objective measurement results of eye characteristics. [Figure 7] FIG. 2 is an explanatory diagram showing a display unit of the ophthalmologic apparatus of the first embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, an ophthalmic apparatus according to an embodiment of the present invention will be described with reference to a first embodiment shown in the drawings.

[0010] Example 1 The ophthalmic apparatus 1 of the first embodiment is an open-eye type ophthalmic apparatus that can measure the eye characteristics of both eyes simultaneously while the subject keeps both eyes open. Note that the ophthalmic apparatus 1 of the first embodiment can also measure the eye characteristics of each eye separately by blocking one eye or turning off the fixation target.

[0011] 1, the ophthalmologic apparatus 1 of the first embodiment includes a support base 10, a measurement unit 20, an examiner's controller 30, a control unit 40, and a subject's controller (not shown). In the following, the left-right direction as seen from the subject is defined as the X direction, the up-down direction (vertical direction) is defined as the Y direction, and the direction perpendicular to the X and Y directions (depth direction) is defined as the Z direction.

[0012] The support base 10 has a support column 11 standing upright from the floor surface and an optometry table 12 supported by the support column 11. The optometry table 12 is a platform on which devices and tools used in optometry, such as the examiner controller 30, are placed and which supports the posture of the examinee. The optometry table 12 may be supported by the support column 11 so that its position in the Y direction (height position) is adjustable.

[0013] The measurement unit 20 has an arm 21, a measurement head 22, and a forehead rest 23. One end of the arm 21 is supported by the tip of the support column 11, and the other end extends from the support column 11 toward the front side (the subject side) along the Z direction, with the measurement head 22 attached to the tip. As a result, the measurement head 22 is suspended from the support column 11 via the arm 21 above the optometry table 12. The arm 21 is movable in the Y direction relative to the support column 11. The arm 21 may also be movable in the X direction or the Z direction relative to the support column 11.

[0014] The measurement head 22 is a part that measures the ocular characteristics of the subject's eye E. The measurement head 22 has a drive unit 22a and a pair of left and right measurement units, a left measurement unit 22L and a right measurement unit 22R, which are provided below the drive unit 22a. The left measurement unit 22L and the right measurement unit 22R are paired to correspond to the subject's left and right eyes, respectively. The left measurement unit 22L incorporates a left measurement optical system 25L that measures the ocular characteristics of the subject's left eye E (left subject eye). The right measurement unit 22R incorporates a right measurement optical system 25R that measures the ocular characteristics of the subject's right eye E (right subject eye). Measurement results by the measurement head 22 are input to the control unit 40.

[0015] The drive unit 22a is a mechanism that drives the left measurement unit 22L and the right measurement unit 22R to move horizontally (X direction), move vertically (Y direction), rotate in the X direction, and rotate in the Y direction, respectively.

[0016] Furthermore, the ophthalmic apparatus 1 of Example 1 can objectively and subjectively measure the ocular characteristics of the subject's eye E. That is, the examiner can use the ophthalmic apparatus 1 to perform any objective test and subjective test. In an objective test, light is irradiated onto the subject's eye E, and information (ocular characteristics) about the subject's eye E is measured based on the detection result of the returned light. Here, the objective test includes measurement for acquiring the ocular characteristics of the subject's eye E and photography for acquiring an image of the subject's eye E. Objective tests include objective refraction measurement (REF measurement), corneal shape measurement (KERATOMETRY), intraocular pressure measurement, fundus photography, tomography (OCT photography) using optical coherence tomography (hereinafter referred to as "OCT"), measurement using OCT, and the like. In a subjective test, a visual target or the like is presented to the subject, and information (ocular characteristics) about the subject's eye E is measured based on the subject's response to the presented visual target or the like. Subjective tests include subjective refraction measurements such as distance tests, intermediate tests, near tests, contrast tests, and glare tests, as well as visual field tests.

[0017] 2, the left measurement optical system 25L and the right measurement optical system 25R built into the measurement head 22 include an observation system 41 for observing the anterior segment of the subject's eye E, a visual target projection system 42 for presenting a visual target to the subject's eye E, an eye refractive power measurement system 43 and a keratomic system 47 (left eye objective measurement system, right eye objective measurement system) for measuring the ocular characteristics of the subject's eye E. The detailed configurations of the left measurement optical system 25L and the right measurement optical system 25R will be described later.

[0018] The forehead rest 23 is provided in the measurement unit 20 and is disposed between the left measurement unit 22L and the right measurement unit 22R. The forehead rest 23 supports the subject's face by bringing part of the subject's face (forehead) into contact with it during measurement of eye characteristics. That is, the subject facing the ophthalmology table 12 presses their forehead against the forehead rest 23 to stabilize the direction and position of their face. The position of the forehead rest 23 is adjusted by moving the arm 21 in the Y direction relative to the support 11.

[0019] The examiner's controller 30 is an information processing device that receives operations by the examiner and outputs a control signal to the control unit 40. The examiner's controller 30 is, for example, a tablet terminal or a smartphone, and is separated from the measurement unit 20 so as to be portable by the examiner. The examiner's controller 30 may be a notebook personal computer, a desktop personal computer, or a controller dedicated to the ophthalmic apparatus 1. The examiner's controller 30 exchanges information with the control unit 40 via wireless communication or network communication.

[0020] 1, the examiner's controller 30 includes a display unit 31, an operation-side control unit (not shown), and input buttons (not shown). The display unit 31 is made up of a touch panel display provided on the surface of the examiner's controller 30, and has input buttons set thereon. The operation-side control unit is made up of a microcomputer built into the examiner's controller 30. The operation-side control unit controls images to be displayed on the display unit 31 based on measurement results and detection results transmitted from the control unit 40. The operation-side control unit also outputs control signals to the control unit 40 in response to operations on the input buttons.

[0021] The control unit 40 is an information processing device provided below the optometry table 12. Based on a control signal transmitted from the examiner's controller 30, the control unit 40 comprehensively controls each part of the measurement unit 20, including the left measurement optical system 25L and the right measurement optical system 25R, each of which has an objective measurement optical system (eye refractive power measurement system 43, keratoconduction system 47) and an optotype projection system 42. The control unit 40 also transmits the measurement results of the ocular characteristics of the subject's eye E measured by the measurement head 22 to the examiner's controller 30.

[0022] Furthermore, when measuring ocular characteristics through objective testing or subjective testing, the control unit 40 first performs a preliminary measurement (step S1), then performs fogging control (step S2), and then measures the ocular characteristics through a main measurement (step S3), as shown in FIG. 3. In the fogging control, the control unit 40 of the first embodiment controls the measurement unit 20 to change the presentation position of the fixation target in a direction that increases the amount of fogging, presenting the fixation target to the subject's eye E, and objectively measuring the ocular characteristics of the subject's eye E in a time series while fogging the subject's eye E. Note that the "amount of fogging" is the amount (strength) of fogging applied to the subject's eye E and is expressed as a diopter equivalent value that indicates the presentation position of the fixation target. The presentation position of the fixation target is then determined according to the amount of fogging. That is, when the amount of fogging is increased, the control unit 40 changes (moves) the presentation position of the fixation target toward the far viewing direction (positive side), and when the amount of fogging is decreased, the control unit 40 changes (moves) the presentation position of the fixation target toward the near viewing direction (negative side).

[0023] When performing fogging control, the control unit 40 determines whether to continue changing the presentation position of the fixation target relative to the subject's eye E, that is, whether to increase the amount of fogging and continue fogging, based on the objective measurement results of the eye characteristics measured over time.The control unit 40 then ends the change of the presentation position of the fixation target when the fluctuations in the objective measurement results converge to a predetermined range.Furthermore, when the fluctuations in the objective measurement results do not converge to a predetermined range, the control unit 40 further changes the presentation position in a direction that increases the amount of fogging, and continues fogging the subject's eye E after increasing the amount of fogging.

[0024] Furthermore, when performing fogging control, the control unit 40 displays a graph showing the relationship between the amount of fogging when the fixation target is presented and the objective measurement results of the eye characteristics measured over time (see FIGS. 5 and 6). Here, a graph G showing the relationship between the amount of fogging and the objective measurement results is displayed on the display unit 31 of the examiner's controller 30, as shown in FIG.

[0025] The detailed configurations of the left measurement optical system 25L and the right measurement optical system 25R will be described below with reference to Fig. 2. The left measurement optical system 25L and the right measurement optical system 25R have the same configuration. Therefore, the following description will omit the description of the right measurement optical system 25R and will only describe the left measurement optical system 25L.

[0026] 2, the left measurement optical system 25L has an observation system 41, a visual target projection system 42, a subjective measurement optical system 44, a first alignment system 45, a second alignment system 46, and an eye refractive power measurement system 43 and a keratologic system 47, which are examples of an objective measurement optical system. Here, the subjective measurement optical system 44, the eye refractive power measurement system 43, and the keratologic system 47 are all measurement optical systems that measure the eye characteristics of the subject's eye E.

[0027] The observation system 41 has an objective lens 41a, a first dichroic filter 41b, a first half mirror 41c, a first relay lens 41d, a second dichroic filter 41e, an imaging lens 41f, and an image pickup device (CCD) 41g.

[0028] In the observation system 41, a light beam reflected by the subject's eye E (anterior segment) passes through the objective lens 41a and is imaged by the imaging lens 41f on the image sensor 41g. As a result, an anterior segment image E' is formed on the image sensor 41g by projecting a keratinizing light beam, a light beam from the first alignment light source 45a, and a light beam (bright spot image Br) from the second alignment light source 46a, which will be described later. The image sensor 41g captures the anterior segment image E' and acquires an image signal of the anterior segment image E'. The control unit 40 controls the display unit 31 of the examiner's controller 30 to display the anterior segment image E' and the like based on the image signal output from the image sensor 41g.

[0029] A keratomic system 47 is provided in front of the objective lens 41a. The keratomic system 47 is an example of an objective measurement optical system, and measures the corneal shape (radius of curvature) of the subject's eye E. The keratomic system 47 has a keratomic plate 47a and a keratomic light source 47b. The keratomic plate 47a is in the shape of a plate with a slit concentric with the optical axis of the observation system 41, and is provided near the objective lens 41a. The keratomic light source 47b is provided in accordance with the slit of the keratomic plate 47a.

[0030] In the keratomileusis system 47, a light beam from the lit keratomileusis light source 47b passes through a slit in the keratomileusis plate 47a, thereby projecting a keratomileusis light beam (a ring-shaped target for measuring corneal curvature) onto the subject's eye E (cornea Ec) to measure the corneal shape. The keratomileusis light beam is reflected by the cornea Ec of the subject's eye E and is imaged on the image sensor 41g by the observation system 41. As a result, the image sensor 41g detects (receives) an image of the ring-shaped keratomileusis light beam. The control unit 40 controls the display unit 31 to display the image of the keratomileusis light beam detected by the image sensor 41g. Furthermore, the control unit 40 measures the corneal shape (radius of curvature) of the subject's eye E using a well-known method based on the image signal detected by the image sensor 41g.

[0031] A first alignment system 45 is provided behind the keratomic system 47 (keratomic plate 47a). The first alignment system 45 aligns the optical system with the subject's eye E in a direction (front-back direction, Z direction) along the optical axis of the observation system 41. The first alignment system 45 has a pair of first alignment light sources 45a and a pair of first projection lenses 45b.

[0032] In the first alignment system 45, the light beams from each first alignment light source 45a are converted into parallel light beams by each first projection lens 45b, and the parallel light beams are projected onto the cornea Ec of the test eye E through alignment holes provided in the keratoplasty plate 47a.

[0033] The control unit 40 or the examiner moves the left measurement unit 22L (or the right measurement unit 22R) in the front-to-back direction based on the bright spot (bright spot image Br) projected onto the cornea Ec, thereby performing alignment in the direction along the optical axis of the observation system 41 (front-to-back direction). When performing alignment in the front-to-back direction, the control unit 40 or the examiner adjusts the position of the left measurement unit 22L (or the right measurement unit 22R) so that the ratio between the distance between the two point images formed by the first alignment light source 45a on the image sensor 41g and the diameter of the keratinizing image falls within a predetermined range.

[0034] The observation system 41 is also provided with a second alignment system (parallel optical system) 46. The second alignment system 46 aligns the optical system with respect to the subject's eye E in directions (up-down and left-right directions; Y direction and X direction) perpendicular to the optical axis of the observation system 41. The second alignment system 46 has a second alignment light source 46a and a second projection lens 46b. The second alignment system 46 also shares a first half mirror 41c, a first dichroic filter 41b, and an objective lens 41a with the observation system 41.

[0035] In the second alignment system 46, a light beam from a second alignment light source (point light source) 46a is converted into a parallel light beam via the objective lens 41a and projected onto the cornea Ec of the subject's eye E. The parallel light beam projected from the second alignment system 46 onto the cornea Ec of the subject's eye E forms a bright spot of alignment light at a position approximately midway between the vertex of the cornea and the center of curvature of the cornea Ec.

[0036] The control unit 40 or the examiner performs alignment in a direction perpendicular to the optical axis of the observation system 41 (up / down direction, left / right direction) by moving the left measurement unit 22L (or the right measurement unit 22R) up / down or left / right based on the bright spot (bright spot image Br) projected (illuminated) onto the cornea Ec.

[0037] The visual target projection system 42 projects a visual target (fixation target) to fixate and fogging the subject's eye E, and presents it on the fundus Ef of the subject's eye E. Furthermore, the subjective measurement optical system 44 projects a visual target onto the subject's eye E during a subjective examination. In the ophthalmologic apparatus 1 of the first embodiment, the visual target projection system 42 and the subjective measurement optical system 44 share optical elements that constitute the optical system.

[0038] The visual target projection system 42 (subjective measurement optical system 44) includes a display 42a, a second half mirror 42b, a second relay lens 42c, a first reflecting mirror 42d, a first focusing lens 42e, a third relay lens 42f, a first field lens 42g, a variable cross cylinder lens (VCC) 42h, a second reflecting mirror 42i, and a third dichroic filter 42j. The visual target projection system 42 (subjective measurement optical system 44) also shares the first dichroic filter 41b and the objective lens 41a with the observation system 41. The visual target projection system 42 (subjective measurement optical system 44) also includes at least two glare light sources 42k that irradiate the subject's eye E with glare light at positions surrounding the optical axis on an optical path separate from the optical path leading to the display 42a, etc., for subjective testing.

[0039] The display 42a displays a fixation target or a dot target as a target to fixate the gaze when performing an objective test or when fogging the subject's eye E, and also displays a subjective test target for subjectively testing the eye characteristics of the subject's eye E (such as visual acuity value and corrective power (distance vision power, near vision power)). The display 42a can use an EL (electroluminescence) or liquid crystal display (LCD), and is controlled by the control unit 40 to display any image. The display 42a is provided on the optical path of the target projection system 42 (subjective measurement optical system 44) at a position conjugate with the fundus Ef of the subject's eye E.

[0040] The first focusing lens 42e is driven to advance and retreat along the optical axis by a drive motor (not shown) controlled by the control unit 40. The control unit 40 can shift the refractive index to the negative side by moving the first focusing lens 42e toward the subject's eye E. The control unit 40 can also shift the refractive index to the positive side (distance vision direction) by moving the first focusing lens 42e in a direction away from the subject's eye E. Therefore, by driving the first focusing lens 42e forward and backward, the control unit 40 changes the presentation position of the optotype displayed on the display 42a, and the examination distance from the presentation position of the optotype to the subject's eye E is changed.

[0041] Furthermore, the visual target projection system 42 (subjective measurement optical system 44) includes a pinhole plate 42p at a position on the optical path that is approximately conjugate with the pupil of the subject's eye E (between the first field lens 42g and the VCC 42h in the example shown in FIG. 2). The pinhole plate 42p is formed of a plate member with a through-hole. The pinhole plate 42p is controlled by the control unit 40 and can be inserted into and removed from the optical path of the visual target projection system 42 (subjective measurement optical system 44). When inserted into the optical path, the through-hole of the pinhole plate 42p is positioned on the optical axis. Furthermore, by inserting the pinhole plate 42p into the optical path during subjective testing, a pinhole test can be performed to determine whether or not the subject's eye E can be corrected with spectacles. Note that the pinhole plate 42p may be provided at a position on the optical path that is approximately conjugate with the pupil of the subject's eye E, and is not limited to the configuration shown in FIG. 2.

[0042] The optotype displayed on the display 42a during subjective testing or the like is not particularly limited as long as it is one used in optometry, and examples thereof include Landolt rings, Snellen charts, and E charts. The optotype may be a still image or a moving image. The ophthalmic apparatus 1 of Example 1 includes a display 42a such as an LCD, which can display optotypes of desired shapes, configurations, and contrasts at a predetermined test distance, enabling multifaceted and detailed eye examinations. The ophthalmic apparatus 1 of Example 1 also includes two displays 42a, one for each of the left and right eyes E to be examined. Therefore, the ophthalmic apparatus 1 can display optotypes that provide parallax at a predetermined test distance (presentation position), enabling easy and precise stereoscopic testing with a natural visual axis orientation.

[0043] Furthermore, in the visual target projection system 42, when fogging the subject's eye E, a fixation target (visual target) is presented at a predetermined presentation position on the subject's eye E. The presentation position of the fixation target is set according to the amount of fogging (strength of the fogging) to be applied to the subject's eye E.

[0044] The eye refractive power measurement system 43 is an example of an objective measurement optical system, and measures the eye refractive power of the subject's eye E. In Example 1, the eye refractive power measurement system 43 has a function of projecting a predetermined measurement pattern onto the fundus Ef of the subject's eye E, and a function of detecting an image of the measurement pattern projected onto the fundus Ef. That is, the eye refractive power measurement system 43 has a ring-shaped light beam projection system 43A that projects a ring-shaped measurement pattern onto the fundus Ef of the subject's eye E, and a ring-shaped light beam receiving system 43B that detects (receives) the reflected light of the ring-shaped measurement pattern from the fundus Ef.

[0045] The ring-shaped light beam projection system 43A includes a reflector light source unit 43a, a fourth relay lens 43b, a pupil ring diaphragm 43c, a second field lens 43d, a perforated prism 43e, and a rotary prism 43f. The ring-shaped light beam projection system 43A also shares a third dichroic filter 42j with the visual target projection system 42 (subjective measurement optical system 44), and shares a first dichroic filter 41b and an objective lens 41a with the observation system 41. The reflector light source unit 43a includes a reflector measurement light source 43g for reflector measurement using, for example, an LED, a collimator lens 43h, a conical prism 43i, and a ring pattern forming plate 43j. The reflector light source unit 43a is controlled by the control unit 40 and moves integrally with the eye refractive power measurement system 43 on the optical axis.

[0046] The ring-shaped beam receiving system 43B has a hole 43p in the aperture prism 43e, a third field lens 43q, a third reflecting mirror 43r, a fifth relay lens 43s, a second focusing lens 43t, and a fourth reflecting mirror 43u. The ring-shaped beam receiving system 43B shares the objective lens 41a, the first dichroic filter 41b, the second dichroic filter 41e, the imaging lens 41f, and the image sensor 41g with the observation system 41. Furthermore, the ring-shaped beam receiving system 43B shares the third dichroic filter 42j with the visual target projection system 42 (subjective measurement optical system 44), and shares the rotary prism 43f and aperture prism 43e with the ring-shaped beam projection system 43A.

[0047] When measuring the ocular refractive power of the subject's eye E using the ocular refractive power measurement system 43, the control unit 40 first turns on the reflector measurement light source 43g. Then, the control unit 40 moves the reflector light source unit 43a of the ring-shaped light beam projection system 43A and the second focusing lens 43t of the ring-shaped light beam receiving system 43B in the optical axis direction. In the ring-shaped light beam projection system 43A, the reflector light source unit 43a emits a ring-shaped measurement pattern, which passes through the fourth relay lens 43b, the pupil ring diaphragm 43c, and the second field lens 43d and then travels to the perforated prism 43e, where it is reflected by the reflecting surface 43v and guided to the third dichroic filter 42j via the rotary prism 43f. The ring-shaped light beam projection system 43A projects the ring-shaped measurement pattern onto the fundus Ef of the eye E by guiding the measurement pattern to the objective lens 41a via the third dichroic filter 42j and the first dichroic filter 41b.

[0048] The ring-shaped luminous flux receiving system 43B collects the ring-shaped measurement pattern formed on the fundus oculi Ef using the objective lens 41a, and passes the light through the first dichroic filter 41b, the third dichroic filter 42j, and the rotary prism 43f to the hole 43p of the aperture prism 43e. The ring-shaped luminous flux receiving system 43B then passes the measurement pattern through the third field lens 43q, the third reflecting mirror 43r, the fifth relay lens 43s, the second focusing lens 43t, the fourth reflecting mirror 43u, the second dichroic filter 41e, and the imaging lens 41f, forming an image on the imaging element 41g. The imaging element 41g then detects the image of the ring-shaped measurement pattern, and the control unit 40 controls the display unit 31 to display the image of the measurement pattern detected by the imaging element 41g. Then, the control unit 40 measures the spherical power, cylindrical power, and axial angle as the eye refractive power based on the image signal from the image pickup element 41g using a known method.

[0049] The configurations of the eye refractive power measurement system 43, the first alignment system 45, the second alignment system 46, and the keratomileusis system 47, as well as the principles of measuring eye refractive power (REF), subjective examination, and corneal shape (KERAT), are well known, and therefore detailed explanations will be omitted.

[0050] The fogging control procedure performed by the control unit 40 of the first embodiment will be described below with reference to the flowchart shown in FIG.

[0051] As shown in FIG. 3, fogging control (step S2) is performed between the preliminary measurement (step S1) and the main measurement (step S3) when an objective test or a subjective test is performed.

[0052] Here, the "preliminary measurement" is a process of focusing the subject's eye E on the fogging start position, and is performed, for example, by the following procedure. That is, the control unit 40 calculates a provisional spherical power S and an astigmatic power C of the subject's eye E based on a captured image of a ring image acquired using the eye refractive power measurement system 43. Then, based on the calculation results of the provisional spherical power S and the astigmatic power C, the control unit 40 controls the second focusing lens 43t to move the focal position of the patterned light to a position corresponding to the equivalent spherical power (S+C / 2) (a position corresponding to the provisional far point: fogging start position).

[0053] Furthermore, "main measurement" is a process of measuring a predetermined target eye characteristic, and for example, when performing objective refraction measurement (REF measurement), it is performed in the following procedure. That is, the control unit 40 causes the ring-shaped light beam projection system 43A to project a ring-shaped measurement pattern onto the fogged fundus Ef of the subject's eye E. Then, the control unit 40 causes the ring-shaped light beam receiving system 43B to detect (receive) the reflected light of the ring-shaped measurement pattern from the fundus Ef, and measures the spherical power, cylindrical power, and axial angle as the eye refractive power using well-known methods based on the image signal from the image sensor 41g.

[0054] The ophthalmic apparatus 1 of the first embodiment is an open-view type ophthalmic apparatus that can measure the eye characteristics of both eyes simultaneously. Therefore, each step of the preliminary measurement, the fogging control, and the main measurement can be performed on both the left and right examinee's eyes E and E simultaneously.

[0055] Furthermore, the ophthalmic apparatus 1 of the first embodiment predetermines the "amount of fogging increase," the "prescribed amount of fogging," and the "threshold for determining fluctuations in objective measurement results" during fogging control. The "amount of fogging increase" refers to the amount of fogging increased when changing the position of the fixation target, and may be, for example, 0.25 diopters on the positive side (in the direction of far vision). The "default amount of fogging" refers to the amount of fogging that triggers a determination as to whether the objective measurement results measured during fogging control have converged, and can be set arbitrarily. For example, the "default amount of fogging" may be 1.5 diopters on the positive side (in the direction of far vision) when the amount of fogging at the start of fogging is 0.0 diopters. The "threshold for determining fluctuations in objective measurement results" refers to a predetermined range for determining whether the objective measurement results measured during fogging control have converged, and may be, for example, ±0.1 diopters.

[0056] In step S201 of the fogging control, the control unit 40 changes the presentation position of the fixation target in a direction that increases the amount of fogging, and then proceeds to step S202. Here, the change amount of the presentation position of the fixation target is predetermined according to the "amount of fogging increase." That is, the control unit 40 changes the presentation position of the fixation target from the currently set position to a position that increases the amount of fogging by a predetermined amount (for example, 0.25 diopters to the positive side). As a result, the fixation target is moved to a position that increases the amount of fogging (a position shifted 0.25 diopters to the positive side). Note that the "amount of fogging increase" (the amount of change in the presentation position of the fixation target) may be determined each time a change is made, based on the objective measurement results of the ocular characteristics measured in step S202. By changing the presentation position of the fixation target, the subject's eye E is fogging at the fixation target position where the amount of fogging has increased.

[0057] In step S202, following the change in the presentation position of the fixation target and the fogging execution by increasing the amount of fogging in step S201, the control unit 40 objectively measures the eye characteristics of the subject's eye E, that is, performs an objective examination, and proceeds to step S203. Here, the objective examination of the subject's eye E is, for example, objective refraction measurement (REF measurement) performed using the eye refractive power measurement system 43. As a result, the control unit 40 objectively measures the eye characteristics while presenting the fixation target by changing the presentation position of the fixation target in a direction that increases the amount of fogging.

[0058] In step S203, following the objective test in step S202, the control unit 40 displays a graph showing the relationship between the current amount of fogging increased in step S201 and the objective measurement results of the ocular characteristics measured in step S202, and then proceeds to step S204. Here, graph G showing the relationship between the amount of fogging and the objective measurement results may be displayed by plotting values ​​as shown in FIG. 5, or may be displayed by connecting the plotted values ​​with a broken line as shown in FIG. 6. Note that in FIG. 6, the results of multiple subjects are overlaid on a single graph G to show that the objective measurement results differ for each subject. Graph G is generated for each subject. Graph G is also displayed on the display unit 31 as shown in FIG. 7. Furthermore, for example, if the objective measurement results are expressed using spherical equivalent power, the range of astigmatism may be indicated on graph G.

[0059] In step S204, following the graph display in step S203, the control unit 40 determines whether the amount of fogging when the objective test was performed in step S202, i.e., the current amount of fogging increased in step S201, has reached a preset "default amount of fogging." If YES (the default amount of fogging has been reached), the process proceeds to step S205. If NO (the default amount of fogging has not been reached), the process returns to step S201.

[0060] Here, when returning from step S204 to step S201, the control unit 40 again changes the presentation position of the fixation target in a direction that increases the amount of fogging. As a result, the subject's eye E is again fogging-up at the fixation target position where the amount of fogging has been further increased. Then, proceeding again to step S202, the control unit 40 objectively measures the eye characteristics of the subject's eye E. That is, the change in the presentation position of the fixation target and the accompanying objective test are repeated until the amount of fogging reaches a predetermined "default fogging amount." As a result, the control unit 40 objectively measures the eye characteristics in a time series while presenting the fixation target by changing its presentation position in a direction that increases the amount of fogging.

[0061] In step S205, following the determination in step S204 that the amount of fogging has reached the preset "default amount of fogging," the control unit 40 determines whether to continue fogging after changing the presentation position of the fixation target based on the objective measurement result measured in step S202. That is, in step S205, the control unit 40 determines whether the objective measurement result of the eye characteristics measured in step S202 has converged.

[0062] If the amount of variation in the objective measurement results between the last measurement and the measurement just before it is greater than a predetermined range (e.g., ±0.1 diopters) (e.g., for subject 3 shown in FIG. 6), the control unit 40 determines that the crystalline lens is tense and not sufficiently fogging. In this case, the control unit 40 determines that the "objective measurement results have not converged (fogging continues)," determines NO in step S205, and returns to step S201. On the other hand, if the amount of variation in the objective measurement results between the last measurement and the measurement just before it is small (e.g., if the amount of variation is within the predetermined range, e.g., for subjects 1 and 2 shown in FIG. 6), the control unit 40 determines that the crystalline lens is relaxed and sufficiently fogging. In this case, the control unit 40 determines that the "objective measurement results have converged (fogging ended)," determines YES in step S205, and proceeds to step S206. In addition, the control unit 40 may analyze the fluctuation in the amount of fogging from the fogging start position, and determine that the "objective measurement results have converged" if it is estimated that the amount of change in the amount of fogging has decreased.

[0063] Then, even when returning from step S205 to step S201, the control unit 40 again changes the presentation position of the fixation target in a direction that increases the amount of fogging. Then, the subject's eye E is fogging again at the fixation target position where the amount of fogging has been further increased. Then, proceeding again to step S202, the control unit 40 objectively measures the eye characteristics of the subject's eye E. That is, changing the presentation position of the fixation target and carrying out the objective test accordingly are repeated until it is determined that the objective measurement results have converged. As a result, the control unit 40 objectively measures the eye characteristics in a time series while presenting the fixation target by changing the presentation position of the fixation target in a direction that increases the amount of fogging.

[0064] In step S206, following the determination that the objective measurement results in step S205 have converged, the control unit 40 estimates the tension tendency of the subject's eye E based on the objective measurement results of the ocular characteristics measured in step S202, notifies the examiner or subject, and proceeds to END. Here, the "tension tendency of the subject's eye E" is information indicating the ease with which the subject's eye E can be readjusted (the degree of relaxation of tension). The "tension tendency of the subject's eye E" can be found from the amount of fluctuation (amount of change) in the objective measurement results from the start of fogging. The control unit 40 may estimate that the subject's eye E's tendency to tense is "prone to tension (not sufficiently fogging, so the degree of relaxation is low and readjustment is likely)" if the amount of change in the objective measurement results from the start of fogging is greater than a predetermined amount (e.g., +0.5 diopters), or may estimate that the subject's eye E's tendency to tense is "prone to tension (not sufficiently fogging, so the degree of relaxation is low and readjustment is likely)" if the sum of the amount of change in the objective measurement results each time the fixation target position moves is greater than a predetermined amount (e.g., +1.0 diopters). Conversely, the control device 40 may estimate that the test eye E's tendency to tense is "unlikely to tense (sufficiently relaxed and unlikely to require readjustment)" if the amount of change in the objective measurement results from the start of fogging is a predetermined amount (e.g., +0.5 diopters) or less, or may estimate that the test eye E's tendency to tense is "unlikely to tense (sufficiently relaxed and unlikely to require readjustment)" if the sum of the amount of change in the objective measurement results each time the fixation target position moves is a predetermined amount (e.g., +1.0 diopters) or less.

[0065] The "tension tendency of the subject's eye E" is notified by displaying it on the display unit 31, issuing a sound, or the like. Note that if the astigmatism power of the subject's eye E is large, the focal depth becomes deep, which may affect the amount of variation in the objective measurement results. Therefore, if the astigmatism power is large (for example, 1.0 D or more), the astigmatism power may be notified.

[0066] The following describes the effects of the ophthalmologic apparatus 1 of the first embodiment.

[0067] When measuring the ocular characteristics of the subject's eye E, the ophthalmologic apparatus 1 of the first embodiment performs fogging control (step S2) between the preliminary measurement (step S1) and the main measurement (step S3). That is, after performing the preliminary measurement (step S1), the control unit 40 changes the presentation position of the fixation target in a direction to increase the amount of fogging according to a predetermined "amount of fogging increase" (step S201). Therefore, the subject's eye E is fogging with the amount of fogging increased, and the control unit 40 objectively measures the ocular characteristics of the subject's eye E in the fogging state (step S202).

[0068] Next, the control unit 40 displays a graph of the relationship between the amount of fogging and the objective measurement result (step S203). Then, the control unit 40 determines whether the amount of fogging has reached the "predetermined amount of fogging" (step S204). Furthermore, if the amount of fogging has reached the "predetermined amount of fogging," the control unit 40 determines whether to continue fogging after changing the presentation position of the fixation target based on whether the objective measurement result has converged (step S205).

[0069] Then, when the objective measurement result has converged (when it is determined that the fogging will not continue after changing the presentation position of the fixation target), the control unit 40 estimates the strain tendency of the subject's eye E based on the objective measurement result and notifies the examiner or subject (step S206). Thereafter, the control unit 40 performs the main measurement (step S3).

[0070] Furthermore, the control unit 40 repeatedly changes the presentation position of the fixation target in a direction that increases the amount of fogging and conducts the objective test until the amount of fogging reaches the "predetermined amount of fogging," the objective measurement results converge, and it determines that the change in the presentation position of the fixation target should not be continued.

[0071] As described above, in the fogging control (step S2), the ophthalmologic apparatus 1 of the first embodiment presents the fixation target to the subject's eye E by changing the presentation position of the fixation target in a direction that increases the amount of fogging, and objectively measures the eye characteristics in a time series while fogging the subject's eye E. That is, the subject's eye E is fogging while the fixation target position is changed in a direction that increases the amount of fogging, and the eye characteristics at that time are objectively measured in a time series. Therefore, the control unit 40 can apply additional fogging as needed while estimating the tension state of the subject's eye E based on the objective measurement results.

[0072] That is, in the example shown in FIG. 6 , for example, for subject 1, indicated by the solid line, there is no difference between the objective measurement value (equivalent spherical power) at a predetermined fogging amount at the start of fogging and the objective measurement value (equivalent spherical power) when the fogging amount is increased by 0.25 diopters from the fogging amount at the start of fogging. In other words, for subject 1, when a fixation target is presented at a position where the fogging amount is a predetermined fogging start amount and fogging is applied, the fluctuation of the objective measurement result is already within a predetermined range. Therefore, the control unit 40 can determine that the “objective measurement result has converged” when the fixation target is presented at the fogging start position, and subject 1’s tension in the test eye E is relaxed when the fixation target is presented at the fogging start position and fogging is applied. Therefore, in the case of subject 1, when the fogging amount reaches the “predetermined fogging amount,” tension in the test eye E is relaxed, and the control unit 40 can determine that additional fogging by increasing the fogging amount is unnecessary.

[0073] Furthermore, for subject 2, shown by the dashed line in FIG. 6 , there is no difference between the objective measurement value (equivalent spherical power) when the fogging amount is increased by 1.0 diopter from the fogging amount at the onset and the objective measurement value (equivalent spherical power) when the fogging amount is increased by 1.25 diopters from the fogging amount at the onset. In other words, for subject 2, when a fixation target is presented at a position where the fogging amount increases by 1.0 diopter from the fogging amount at the onset and fogging is applied, the fluctuation in the objective measurement result falls within a predetermined range. Therefore, when subject 2 presents a fixation target at a position where the fogging amount increases by 1.0 diopter from the fogging amount at the onset and fogging is applied, tension in subject E is relaxed. Therefore, in the case of subject 2, when the fogging amount reaches the “prescribed fogging amount,” tension in subject E is relaxed, and the control unit 40 can determine that additional fogging by increasing the fogging amount is unnecessary.

[0074] On the other hand, for subject 3, shown by the dashed-dotted line in Figure 6, even if the fixation target presentation position is gradually changed in a direction that increases the amount of fogging and the fixation target presentation position is gradually moved toward the positive side (distance viewing direction), the objective measurement value (spherical equivalent power) continues to fluctuate. Therefore, even if subject 3 is presented with a fixation target at a position where the amount of fogging increases by +1.5 diopters from the amount of fogging at the start of fogging and fogging is performed, the fluctuations in the objective measurement results do not fall within the specified range, and it is not determined that the "objective measurement results have converged." Therefore, in the case of subject 3, even if the amount of fogging reaches the "specified amount of fogging," the tension in subject's eye E does not ease, and the control unit 40 can determine that additional fogging by further increasing the amount of fogging is necessary.

[0075] This allows the ophthalmic apparatus 1 to appropriately release the accommodation of the subject's eye E even in a state of pseudomyopia, for example. Furthermore, the control unit 40 or the examiner can grasp the relationship between the presentation position of the fixation target and the objective measurement results in chronological order. Therefore, the control unit 40 or the examiner can determine whether the amount of fogging (fixation target position) caused the crystalline lens of the subject's eye E to relax, for example, from the presentation position of the fixation target at the timing when the objective measurement results converge, or determine whether pseudomyopia is present, based on whether the objective measurement results fluctuate with a change in the presentation position of the fixation target. Furthermore, the ophthalmic apparatus 1 can determine whether there is a possibility of insufficient fogging, etc., based on fluctuations in the objective measurement results.

[0076] Furthermore, in the ophthalmologic apparatus 1 of Example 1, the control unit 40 determines whether to continue fogging after changing the presentation position of the fixation target based on the objective measurement results of the eye characteristics measured in time series (step S205). That is, the ophthalmologic apparatus 1 determines whether to start the main measurement based on the objective measurement results of the eye characteristics measured in time series during fogging control. This allows the next process (main measurement) to be started promptly at a timing when the subject's eye E is appropriately fogging, thereby preventing the examination time from being unnecessarily extended and the burden on the subject from being unnecessarily increased.

[0077] Furthermore, in the ophthalmic apparatus 1 of Example 1, the control unit 40 estimates and notifies the subject's eye E of its tendency to tense based on the objective measurement results of the eye characteristics measured over time (step S206). This allows the examiner or subject to easily grasp the subject's tendency to tense. The examiner can then perform the main measurement or re-fogging after grasping the subject's tendency to tense. That is, if the objective measurement results fluctuate significantly from the start of fogging (if the subject's eye E is estimated to be "prone to tension"), even if the state of tension is alleviated at the end of fogging control, there is a high possibility that accommodation will fluctuate during the main measurement, such as subjective measurement. Therefore, attention must be paid to the state of tension of the subject's eye E during the main measurement. The ophthalmic apparatus 1 of Example 1 allows the examiner to grasp the state of tension of the subject's eye E before the main measurement, allowing the examiner to monitor the state of tension of the subject's eye E while performing the main measurement.

[0078] Furthermore, in the ophthalmologic apparatus 1 of the first embodiment, the control unit 40 displays a graph of the relationship between the amount of fogging when presenting the fixation target and the objective measurement results of the eye characteristics measured over time (step S203). This makes it easier for the examiner or subject to understand the relationship between the amount of fogging and the objective measurement results of the subject's eye E, and allows the examiner or subject to more accurately understand the state of tension in the subject's eye E.

[0079] The ophthalmic apparatus 1 of Example 1 also includes an eye refractive power measurement system 43 and a keratoconstrictor system 47 of the left measurement optical system 25L that objectively measures the eye characteristics of the left subject's eye E, and an eye refractive power measurement system 43 and a keratoconstrictor system 47 of the right measurement optical system 25R that objectively measures the eye characteristics of the right subject's eye E. In other words, the ophthalmic apparatus 1 of Example 1 is an open-lens type ophthalmic apparatus that can measure each of the subject's left and right eyes E. This allows the ophthalmic apparatus 1 to measure the eye characteristics of both eyes simultaneously, to fog both eyes simultaneously, and to set different presentation positions of the fixation target for the left and right eyes. This allows the adjustment of each of the left and right subject's eyes E to be appropriately released.

[0080] Furthermore, since the ophthalmic apparatus 1 of Example 1 is of the open-eye type, the ophthalmic apparatus 1 can simultaneously display a graph G showing the relationship between the amount of fogging and the objective measurement results of the eye characteristics measured over time for both eyes, as shown in Fig. 7. This allows the examiner to compare the graphs G displayed for the left and right eyes E to determine, for example, whether the examinee has anisometropia.

[0081] The ophthalmic device of the present invention has been described above based on Example 1, but the specific configuration is not limited to this Example, and design changes and additions are permitted as long as they do not deviate from the gist of the invention according to each claim.

[0082] That is, the ophthalmic apparatus 1 of Example 1 is an example of an open-view type ophthalmic apparatus that can objectively measure the ocular characteristics of the left and right subject's eyes E separately. However, the ophthalmic apparatus of the present invention is not limited to this, and may be a monocular type ophthalmic apparatus that measures the ocular characteristics of one eye at a time. That is, the ophthalmic apparatus of the present invention may be equipped with an objective measurement optical system that objectively measures the ocular characteristics of the left subject's eye E and the ocular characteristics of the right subject's eye E separately.

[0083] Furthermore, the left measurement optical system 25L and the right measurement optical system 25R of the ophthalmic apparatus 1 of Example 1 have at least a visual target projection system 42 (subjective measurement optical system 44), an eye refractive power measurement system 43, and a keratomileusis system 47. That is, Example 1 shows an example in which the ophthalmic apparatus 1 has a so-called multi-function that performs autorefraction and keratomileusis measurement under binocular vision and subjective refraction testing in a single device. However, the ophthalmic apparatus 1 is not limited to this, and may be, for example, an apparatus that can measure only the eye refractive power of the subject's eye E. In this case, it is desirable that the ophthalmic apparatus has a transmission mechanism that enables transmission of information to another ophthalmic apparatus equipped with a measurement optical system that measures eye characteristics.

[0084] In the case of an ophthalmic device equipped with a transmission mechanism, the objective measurement results of the eye characteristics measured in time series can be transmitted to the other ophthalmic device via the transmission mechanism for use in setting the measurement state of the measurement optical system of the other ophthalmic device. This allows the other ophthalmic device to use the objective measurement results during fog acquired by the ophthalmic device 1 for its own setting. In other words, by providing the transmission mechanism, the control unit 40 can link the ophthalmic device 1 of Example 1 with the other ophthalmic device.

[0085] In addition, in Example 1, the position of the fixation target is changed in a direction that gradually increases the amount of fogging, and the ocular characteristics of the subject's eye E are objectively measured each time. However, the manner in which the position of the fixation target is changed and the timing at which the ocular characteristics are objectively measured are not limited to this. For example, the control unit 40 may continuously (continuously) measure the objective ocular characteristics of the subject's eye E while gradually changing the position of the fixation target in a non-stepwise manner and changing the position of the fixation target in a direction that gradually increases the amount of fogging. In this case, the objective test can be performed continuously (continuously) while the position of the fixation target is changed in a non-stepwise manner, and the amount of fogging at which the accommodation of the subject's eye E is released can be accurately determined. In other words, objectively measuring the ocular characteristics over time includes objectively testing the ocular characteristics multiple times while the subject's eye E is fogging, and objectively testing the ocular characteristics continuously (continuously) for a certain period while the subject's eye E is fogging.

[0086] Furthermore, in the first embodiment, an example in which an objective test is performed in the main measurement (step S3) has been shown. However, in the main measurement, after the objective test, a subjective test may be performed using the subjective measurement optical system 44. In this case, before the subjective test is performed, the settings of the subjective measurement optical system 44 may be adjusted based on the objective measurement results of the eye characteristics measured in time series during fogging control.

[0087] In addition, in the first embodiment, an example was shown in which it was determined whether the objective measurement result had converged on the condition that the amount of fogging had reached a predetermined "predetermined amount of fogging." However, the control unit 40 may determine whether the objective measurement result had converged even if the amount of fogging had not reached the "predetermined amount of fogging," and may terminate the fogging control (determine not to continue changing the presentation position of the fixation target) and perform the actual measurement when the objective measurement result had converged. In other words, it is not necessary to determine whether the amount of fogging had reached the "predetermined amount of fogging" (step S204 shown in FIG. 4).

[0088] Furthermore, the control unit 40 may move the fixation target so as to achieve a predetermined amount of fogging that has been set in advance, and then perform an objective test on the subject's eye E, and determine whether or not the objective measurement result has changed.

[0089] Furthermore, in the ophthalmologic apparatus 1 of Example 1, an example has been shown in which a graph is displayed showing the relationship between the amount of fogging and the objective measurement result each time the ocular characteristics of the subject's eye E are objectively measured. However, the graph display may be displayed all at once at any timing, such as when fogging control ends (when the objective measurement results converge) or when necessary measurements such as the main measurement are completed. In addition, the graph G may be displayed as a pop-up on the display unit 31 as shown in FIG. 7, or may be displayed full-screen on the display unit 31.

[0090] The control unit 40 also performs an objective test on the subject's eye at a high speed (e.g., 30 Hz) while changing the presentation position of the fixation target at a constant speed until the amount of fogging increases by a predetermined amount, and performs frequency analysis of the objective measurement results. Then, based on the amount of frequency components related to the accommodative microfluctuation of the subject's eye E, it may be determined that the accommodative microfluctuation has been relaxed, thereby determining that the objective measurement results have converged.

[0091] Furthermore, if the objective measurement result fluctuates in the negative direction (near vision direction), it is possible that the subject's eye E has adjusted regardless of the position of the fixation target. Therefore, the control unit 40 may return the presentation position of the fixation target so that the amount of fogging is the same as before the objective measurement result fluctuated in the negative direction, present the fixation target at the returned position, apply fogging again, and then start the actual measurement.

[0092] Furthermore, if it is known that the objective measurement results have converged before the amount of fogging reaches a predetermined "predetermined amount of fogging," the control unit 40 returns the presentation position of the fixation target so that the amount of fogging is the same as when the objective measurement results converged before the amount of fogging reaches the "predetermined amount of fogging."The control unit 40 may then present the fixation target at the returned position, apply fogging, and start the actual measurement.

[0093] The control unit 40 may also set an upper limit for the amount of fogging (e.g., +3.0 diopters) and terminate fogging control when the amount of fogging reaches the upper limit, even if the objective measurement results do not converge. In this case, the control unit 40 notifies the examiner, etc., in step S206 of the tension tendency of the subject's eye E and that the tension of the subject's eye E has not been relaxed. In other words, when the tension of the subject's eye E has not been relaxed, the control unit 40 may notify both the tension tendency and the tension state of the subject's eye E. Note that the "tension state of the subject's eye E" is information indicating whether the tension of the subject's eye E has been relaxed. In addition, in the first embodiment, when the tension of the subject's eye E has been relaxed, the control unit 40 does not notify the "tension state of the subject's eye E," i.e., that the tension of the subject's eye E has been relaxed. However, the control unit 40 may also notify the "tension state of the subject's eye E" regardless of whether the tension has been relaxed.

[0094] Furthermore, in Example 1, the control unit 40 reports the "tension tendency of the subject's eye E" and, if the tension of the subject's eye E has not been alleviated, reports the "tension state of the subject's eye E." However, the control unit 40 may not report the "tension tendency of the subject's eye E," but may simply report whether or not the tension of the subject's eye E has been alleviated, that is, only the "tension state of the subject's eye E." Furthermore, the control unit 40 does not necessarily have to report the "tension tendency of the subject's eye E" and the "tension state of the subject's eye E." [Explanation of symbols]

[0095] 1 Ophthalmology equipment 25L Left measurement optical system 25R Right measurement optical system 40 Control Unit 41 Observation System 42 Visual target projection system 43 Eye refractive power measurement system (objective measurement optical system) 44 Subjective Measurement Optical System 47 Keratoconjunction (Objective Measurement Optical System)

Claims

1. an objective measurement optical system that objectively measures ocular characteristics of a subject's eye; a target projection system that presents a fixation target at a predetermined presentation position to the subject's eye and fogs the subject's eye; a control unit that controls the objective measurement optical system and the visual target projection system, the control unit objectively measures the eye characteristics in a time series while changing the presentation position of the fixation target in a direction that increases the amount of fogging and presenting the fixation target; Based on the objective measurement results of the eye characteristics measured in time series, a strain tendency of the subject's eye, which indicates a susceptibility to fogging for each subject's eye, is estimated, and the estimated strain tendency is notified. An ophthalmic device characterized by:

2. 2. The ophthalmic apparatus according to claim 1, The control unit sets an amount of fogging to be increased when changing the presentation position of the fixation target based on the objective measurement results of the eye characteristics measured in time series. An ophthalmic device characterized by:

3. 3. The ophthalmic apparatus according to claim 1, The control unit changes the presentation position of the fixation target based on the objective measurement results of the eye characteristics measured in time series, and determines whether or not to continue fogging the subject's eye. An ophthalmic device characterized by:

4. 4. The ophthalmic apparatus according to claim 3, The control unit terminates the change of the presentation position of the fixation target when the variation in the objective measurement result converges to a predetermined range that has been set in advance, and when the variation in the objective measurement result does not converge to the predetermined range, changes the presentation position of the fixation target in a direction that increases the amount of fogging and continues to fogging the subject's eye. An ophthalmic device characterized by:

5. The ophthalmic apparatus according to any one of claims 1 to 4, The control unit notifies the patient of a state of tension of the subject's eye based on objective measurement results of the eye characteristics measured in time series. An ophthalmic device characterized by:

6. The ophthalmic apparatus according to any one of claims 1 to 5, The control unit displays a graph of the relationship between the amount of fogging when the fixation target is presented and the objective measurement results of the eye characteristics measured in time series. An ophthalmic device characterized by:

7. The ophthalmic apparatus according to any one of claims 1 to 6, a subjective measurement optical system for subjectively measuring the eye characteristics, The control unit adjusts settings of the subjective measurement optical system based on objective measurement results of the eye characteristics measured in time series, and measures the eye characteristics using the subjective measurement optical system. An ophthalmic device characterized by:

8. The ophthalmic apparatus according to any one of claims 1 to 7, The objective measurement optical system includes a left eye objective measurement system that objectively measures the eye characteristics of the left eye to be examined, and a right eye objective measurement system that objectively measures the eye characteristics of the right eye to be examined. An ophthalmic device characterized by:

9. The ophthalmic apparatus according to any one of claims 1 to 7, The objective measurement optical system objectively measures the eye characteristics of the left eye and the right eye, respectively. An ophthalmic device characterized by:

10. The ophthalmic apparatus according to any one of claims 1 to 9, a transmission mechanism that enables transmission of information to another ophthalmic apparatus that includes a subjective measurement optical system for subjectively measuring ocular characteristics of the subject's eye, The control unit transmits the objective measurement results of the eye characteristics measured in time series to the other ophthalmic device via the transmission mechanism to be used for setting the measurement state of the subjective measurement optical system provided in the other ophthalmic device. An ophthalmic device characterized by:

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