Ophthalmologic device and operation method of ophthalmologic device

Abstract

To provide an ophthalmologic device that can execute faster and simpler state confirmation for a measurement head using a schematic eye compared to conventional techniques and an operation method of the ophthalmologic device.SOLUTION: An ophthalmologic device includes: a face support unit 12 that supports the face of a subject; a measurement head 14 that measures eye characteristics of the eye to be examined E; a movement mechanism 13 that moves the measurement head 14; a schematic eye 18 that is fixed at a position different from a face arrangement region where the face of the subject is arranged in the face support unit 12; a schematic eye measurement control unit 42 that drives the movement mechanism 13 to move the measurement head 14 to a schematic eye measurement position where it can measure the eye characteristics of the schematic eye 18 and executes measurement of the eye characteristics of the schematic eye 18 with the measurement head 14 at the schematic eye measurement position; and a determination unit 43 that determines whether the measurement head 14 is normal on the basis of data (applanation waveform W1) obtained from the measurement of the eye characteristics of the schematic eye 18 with the measurement head 14.SELECTED DRAWING: Figure 7

Description

[Technical field]

[0001] The present invention relates to an ophthalmic apparatus for measuring ocular characteristics of a subject's eye and an operation method of the ophthalmic apparatus. [Background technology]

[0002] As one of the ophthalmic devices for measuring the ocular characteristics of a subject's eye, a non-contact tonometer that measures the intraocular pressure of the subject's eye without contact is known (see, for example, Patent Document 1). A spray mechanism composed of a piston, a cylinder, a chamber, a nozzle, etc. is provided in the measurement head of the non-contact tonometer. As a result, the non-contact tonometer measures the intraocular pressure value of the subject's eye without contacting the cornea by spraying air from the nozzle onto the cornea of ​​the subject's eye to deform the cornea and detect the state of deformation.

[0003] The non-contact tonometer described in Patent Document 1 detects the degree of dirt on the chamber window glass and cover glass of the measurement head using a model eye (glass ball) fixed on the chin rest of the face support part that supports the face of the subject. The non-contact tonometer described in Patent Document 1 first irradiates alignment index light from the projection optical system of the measurement head toward the model eye on the chin rest, and receives the reflected light of the alignment index light reflected by the model eye with the light receiving optical system of the measurement head. Next, the non-contact tonometer described in Patent Document 1 calculates the degree of dirt on the chamber window glass and cover glass with an arithmetic circuit based on the amount of reflected light received by the light receiving optical system. The non-contact tonometer described in Patent Document 1 then displays the calculation result of the degree of dirt calculated by the arithmetic circuit on a monitor.

[0004] In addition, when a non-contact tonometer is started up (when the power is turned on), a so-called "empty measurement" may be performed, which is an intraocular pressure measurement without the subject eye or the model eye. By performing this empty measurement, any dust in the nozzle can be removed by wind pressure. Also, if there is a large blockage in the nozzle, the piston will not move, so it is possible to check for an abnormality from the change in the pressure inside the chamber. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2002-065612 A Summary of the Invention [Problem to be solved by the invention]

[0006] If the chamber window glass and cover glass of the measurement head of the non-contact tonometer are dirty, the measurement head is not normal, and the measurement accuracy of the non-contact tonometer may decrease. For this reason, as described in Patent Document 1, it is desirable to check in advance whether the measurement head is normal using a model eye.

[0007] However, in the non-contact tonometer described in Patent Document 1, when checking the state of the measurement head, the examiner needs to fix a model eye on the chin rest, and after completing this check, the examiner needs to remove the model eye from the chin rest. Therefore, in the non-contact tonometer described in Patent Document 1, the examiner needs to fix and remove the model eye every time the state of the measurement head is checked, which is time-consuming and laborious. Note that the non-contact tonometer described in Patent Document 1 cannot detect anything other than dirt on the chamber window glass and cover glass to check the state of the measurement head, for example, it cannot detect adhesion (foreign matter) to the nozzle.

[0008] Furthermore, even if the above-mentioned empty measurement is performed, if there is minute adhesion inside the nozzle that cannot be removed by the air pressure of this empty measurement, no noticeable change will be seen in the pressure inside the chamber, but the airflow ejected from the nozzle will be disturbed. In this case, the cornea cannot be applanated sufficiently, making it difficult to accurately measure the intraocular pressure of the examined eye.

[0009] The present invention has been made in consideration of the above circumstances, and has an object to provide an ophthalmic device and an operating method for an ophthalmic device that enable confirmation of the state of a measuring head using a model eye more simply and in a shorter time than conventional methods. [Means for solving the problem]

[0010] An ophthalmologic apparatus for achieving the object of the present invention comprises a face support unit that supports the face of a subject, a measurement head that measures ocular characteristics of the subject's eye, a moving mechanism that moves the measurement head, a model eye that imitates the human eye and is fixed to a position on the face support unit that is different from the face placement area where the subject's face is placed, a model eye measurement control unit that drives the moving mechanism to move the measurement head to a model eye measurement position where the ocular characteristics of the model eye can be measured and performs measurement of the ocular characteristics of the model eye using the measurement head at the model eye measurement position, and a judgment unit that judges whether the measurement head is normal or not based on data obtained from the measurement of the ocular characteristics of the model eye using the measurement head.

[0011] According to this ophthalmologic apparatus, the examiner does not need to attach (fix) and detach the model eye.

[0012] In an ophthalmologic apparatus according to another aspect of the present invention, the model eye is integrated with the face support unit, which eliminates the need for the examiner to attach and detach the model eye.

[0013] In an ophthalmologic apparatus according to another aspect of the present invention, the face support unit includes a forehead rest that is in contact with the forehead of the examinee, and the model eye is fixed to a head-facing surface of the forehead rest that faces the measurement head, thereby eliminating the need for the examiner to attach and detach the model eye.

[0014] In an ophthalmologic apparatus according to another aspect of the present invention, the face support unit includes a cover that is movable between a protective position that covers the model eye and an exposed position that exposes the model eye, thereby preventing a subject or the like from accidentally touching the model eye.

[0015] In an ophthalmologic device according to another aspect of the present invention, the cover is provided so as to be displaceable between a protected position and an exposed position rotated upward from the protected position around a rotation axis parallel to the left-right direction when viewed from the measurement head, and while the model eye measurement control unit drives the moving mechanism to move the measurement head to the model eye measurement position, the measurement head presses the cover in the protected position upward to displace the cover to the exposed position, and when the model eye measurement control unit drives the moving mechanism to retract the measurement head from the model eye measurement position, the cover is displaced from the exposed position to the protected position. This allows the measurement head moved by the moving mechanism to be used to automatically displace the cover between the protected position and the exposed position.

[0016] In the ophthalmologic apparatus according to another aspect of the present invention, a cover rotation mechanism is provided that displaces the cover between the protection position and the exposure position, whereby the cover can be automatically displaced between the protection position and the exposure position.

[0017] In the ophthalmologic apparatus according to another aspect of the present invention, a warning unit is provided that issues warning information when the judgment unit judges that the measurement head is not operating normally. This makes it possible to prompt the examiner to inspect the measurement head. In addition, it is possible to prevent a decrease in the measurement accuracy of eye characteristics and a burden on the examinee due to redoing the measurement.

[0018] In an ophthalmologic apparatus according to another aspect of the present invention, a measurement head is provided for non-contact measurement of the intraocular pressure value of the test eye as an ocular characteristic of the test eye, the measurement head having at least a blowing mechanism for blowing air from a nozzle onto the cornea of ​​the test eye, a projection optical system for projecting a light beam onto the cornea, and a light receiving optical system for receiving reflected light of the light beam reflected by the cornea and outputting a light receiving signal, and a model eye measurement control unit executes a movement process for driving the movement mechanism to move the measurement head to a model eye measurement position, and when the movement process is completed, a blowing process for driving the blowing mechanism to blow air from the nozzle onto the model eye, a projection process for projecting a light beam from the projection optical system onto the model eye while the blowing process is being executed, and a signal output process for outputting a light receiving signal that receives the reflected light of the light beam reflected by the model eye from the light receiving optical system while the blowing process is being executed, and a determination unit determines whether or not the measurement head is normal by determining the presence or absence of adhesions on the nozzle based on a time series change in the light receiving signal output from the light receiving optical system. This makes it possible to detect adhesion of matter to the nozzle.

[0019] In an ophthalmologic apparatus according to another aspect of the present invention, a measuring head for measuring the ocular refractive power of the subject eye as an ocular characteristic of the subject eye is provided, a model eye measurement control unit executes a moving process for driving a moving mechanism to move the measuring head to a model eye measurement position, and a measuring process for measuring the ocular refractive power of the model eye by the measuring head when the moving process is completed, and a determination unit determines whether or not the measuring head is normal based on the measurement result of the ocular refractive power of the model eye by the measuring head and the measurement result of the ocular refractive power of a known model eye. This makes it possible to determine whether or not the measuring head for measuring the ocular refractive power is normal.

[0020] An operating method of an ophthalmologic apparatus for achieving the object of the present invention is an operating method of an ophthalmologic apparatus equipped with a face support section that supports the face of a subject, a measurement head that measures ocular characteristics of the subject's eye, and a moving mechanism that moves the measurement head, the operating method including a model eye measurement step of driving the moving mechanism to move the measurement head to a model eye measurement position where the ocular characteristics of a model eye that mimics a human eye fixed at a position of the face support section different from the face placement area where the subject's face is placed can be measured, and measuring the ocular characteristics of the model eye using the measurement head at the model eye measurement position, and a judgment step of judging whether the measurement head is normal or not based on data obtained by measuring the ocular characteristics of the model eye using the measurement head. Effect of the Invention

[0021] The present invention makes it possible to check the state of a measuring head using a model eye more easily and in a shorter time than in the past. [Brief description of the drawings]

[0022] [Figure 1] FIG. 1 is a side view of a non-contact tonometer according to a first embodiment. [Diagram 2] 1 is a perspective view of a face support portion as viewed from the measuring head side. [Diagram 3] FIG. [Figure 4] 1 is a schematic top view of multiple types of optical systems in a measurement head as viewed from above (Y direction). [Diagram 5] 1 is a schematic side view of a plurality of types of optical systems in a measurement head as viewed from the side (X direction). [Figure 6] FIG. 2 is a functional block diagram of a control device. [Figure 7] 13 is an explanatory diagram for explaining auto-alignment of the measuring head with respect to the model eye by the model eye measurement control unit. FIG. [Figure 8] 1 is an explanatory diagram showing an air flow blown onto the surface of a model eye from a normal nozzle with no attached matter. FIG. [Figure 9]13 is a graph showing an applanation waveform showing a time series change in an applanation signal output from an applanation detection optical system when air is blown onto a model eye from a normal nozzle, and an internal pressure waveform showing a time series change in the internal pressure of a chamber output from a pressure sensor. [Figure 10] FIG. 13 is an explanatory diagram showing an air flow being blown onto the surface of a model eye from a nozzle having minute deposits attached thereto that may affect measurement. [Figure 11] 13 is a graph showing an applanation waveform showing a time series change in an applanation signal output from an applanation detection optical system when air is blown onto a model eye from a nozzle having minute deposits attached thereto that may affect measurement, and an internal pressure waveform showing a time series change in the internal pressure of a chamber output from a pressure sensor. [Figure 12] 13A and 13B are diagrams illustrating an example of warning information displayed on the monitor by a warning control unit. [Figure 13] 11 is a flowchart showing the flow of a head state confirmation process of the measurement head of the non-contact tonometer. [Figure 14] FIG. 11 is an enlarged side view of a forehead rest and a model eye of the non-contact tonometer of the second embodiment. [Figure 15] 13 is an explanatory diagram for explaining automatic rotation of the cover from the protection position to the exposure position when checking the head state of the measuring head. FIG. [Figure 16] 13 is an explanatory diagram for explaining automatic rotation of the cover from the exposed position to the protected position after the head state of the measuring head is confirmed. FIG. [Figure 17] FIG. 13 is an explanatory diagram for explaining a modified example of the non-contact tonometer of the second embodiment. [Figure 18] FIG. 11 is a side view of a refractometer according to the third embodiment. [Figure 19] FIG. 11 is a side view of the model eye of the third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] [First embodiment] Fig. 1 is a side view of a non-contact tonometer 10 of a first embodiment. As shown in Fig. 1, the non-contact tonometer 10 corresponds to an ophthalmic device of the present invention, and performs non-contact measurement of an intraocular pressure value as an ocular characteristic of a subject's eye E. The non-contact tonometer 10 includes a base 11, a face support unit 12, a moving mechanism 13, a measuring head 14, a monitor 15, and a control device 16.

[0024] In the figure, among the mutually orthogonal XYZ directions (three-axis directions), the Y direction is the up-down direction, the Z direction is the front-back direction (also called the working distance direction) moving toward or away from the subject (subject's eye E), and the X direction is the left-right direction perpendicular to both the up-down direction and the front-back direction. In addition, in the Z direction (front-back direction), the side approaching the subject's eye E (subject) is called the front side in the Z direction, and the side moving away from the subject's eye E (subject) is called the rear side in the Z direction.

[0025] A face support part 12 and a moving mechanism 13 are provided on the base 11 from the front side in the Z direction to the rear side in the Z direction. The base 11 supports a measuring head 14 via the moving mechanism 13 so as to be movable in the X, Y and Z directions.

[0026] The face support part 12 is fixed to the base 11. The face support part 12 includes a chin rest part 12a for receiving the subject's chin, a forehead rest part 12b against which the subject's forehead comes into contact, and a pair of supports 12c for supporting the forehead rest part 12b, and supports the subject's face.

[0027] Fig. 2 is a perspective view of the face support part 12 as viewed from the side of the measurement head 14. As shown in Fig. 2 and the already-described Fig. 1, a model eye 18 simulating a human eye is fixed to the face support part 12 at a position different from the face arrangement region where the face of the subject supported by the face support part 12 is arranged, here, on the head opposing surface 17 of the forehead rest part 12b that faces the measurement head 14.

[0028] Here, "a position different from the face placement area" refers to a position that does not prevent the face support part 12 from supporting the subject's face when measuring the intraocular pressure of the subject's eye E, that is, a position where it is not necessary to remove the model eye 18 when measuring the intraocular pressure of the subject's eye E. In addition, "a position different from the face placement area" is also a position where the measurement head 14 (nozzle 21b described below) can be aligned with respect to this position. Therefore, the model eye 18 may be fixed to a position other than the head opposing surface 17 as long as it is a "position different from the face placement area" of the face support part 12, and may be fixed to the support 12c, for example.

[0029] Fig. 3 is an enlarged side view of the model eye 18. As shown in Fig. 3, the model eye 18 is fixed undetachably to the head-facing surface 17 of the forehead rest 12b, and is integrated with the forehead rest 12b (face support part 12). Note that the model eye 18 may be fixed detachably to the head-facing surface 17 of the forehead rest 12b.

[0030] The model eye 18 is formed, for example, from a thin film of rubber or the like into a spherical shape (or a semi-spherical shape), and is deformed in the same manner as the cornea Ec of the subject eye E (see FIG. 4) when air is blown onto it from nozzle 21b of measurement head 14. This model eye 18 is used to check the head condition to confirm whether or not measurement head 14, which will be described later, is normal. There are no particular limitations on the shape and structure of model eye 18, so long as it can be used for measuring intraocular pressure with non-contact tonometer 10.

[0031] Returning to Figure 1, the measurement head 14 measures the intraocular pressure value of the test eye E in a non-contact manner by blowing air from the nozzle 21b toward the cornea Ec (see Figure 4) of the test eye E to deform the cornea Ec and detect the deformed state.

[0032] The monitor 15 is, for example, a touch panel monitor, and is attached to the back side of the measurement head 14. Under the control of the control device 16 described later, the monitor 15 displays various images including a photographed image (observation image) of the subject's eye E photographed by the measurement head 14, measurement results of the intraocular pressure value of the subject's eye E, and a menu screen for performing various operations and various settings. The monitor 15 also displays various warning information under the control of the control device 16, which will be described in detail later (see FIG. 12).

[0033] Fig. 4 is a schematic top view of the multiple types of optical systems in the measurement head 14 as viewed from above (Y direction). Fig. 5 is a schematic side view of the multiple types of optical systems in the measurement head 14 as viewed from the side (X direction).

[0034] As shown in Figures 4 and 5, the measurement head 14 includes an anterior eye observation optical system 21, an XY alignment index projecting optical system 22, a fixation target projecting optical system 23, an applanation detection optical system 24, a Z alignment index projecting optical system 25, a Z alignment detection optical system 26, and a spraying mechanism 34.

[0035] The anterior-segment observation optical system 21 is used for observing the anterior segment of the subject's eye E and for XY-direction XY alignment of the measurement head 14 with respect to the subject's eye E. An anterior-segment illumination light source 21a (see FIG. 4) is provided in the anterior-segment observation optical system 21. Also, on the optical axis O1 of the anterior-segment observation optical system 21, there are provided an air-blowing nozzle 21b, an anterior-segment window glass 21c (see FIG. 5) that holds the tip of the nozzle 21b, a chamber window glass 21d, a half mirror 21e, a half mirror 21g, an objective lens 21f, and an image sensor 21i.

[0036] The anterior-segment illumination light sources 21a are provided at a plurality of positions around the anterior-segment window glass 21c, and directly illuminate the anterior segment of the subject's eye E.

[0037] The nozzle 21b is connected to a chamber 34a (see FIG. 5) of the spray mechanism 34, and blows air onto the cornea Ec of the eye E to be examined.

[0038] An image of the anterior segment of the test eye E (image light from the anterior segment) passes outside the nozzle 21b, through the anterior segment window glass 21c, the glass plate 34b described below, the chamber window glass 21d, the half mirror 21g, and the half mirror 21e, and is formed on the light receiving surface of the imaging element 21i by the objective lens 21f.

[0039] The imaging element 21i is, for example, a CCD (Charge Coupled Device) type or CMOS (complementary metal oxide semiconductor) type image sensor. The imaging element 21i captures an image of the anterior segment incident on its light receiving surface to generate an imaging signal, and outputs the imaging signal to the control device 16. As a result, under the control of the control device 16, an observation image of the anterior segment of the subject's eye E based on the imaging signal output from the imaging element 21i is displayed on the monitor 15.

[0040] The anterior eye observation optical system 21 also guides the reflected light of the XY alignment index light projected from the XY alignment index projecting optical system 22 to the subject's eye E by the cornea Ec to the light receiving surface of the image sensor 21i. This reflected light passes through the nozzle 21b, the chamber window glass 21d, the half mirror 21g, and the half mirror 21e, and is imaged on the light receiving surface of the image sensor 21i by the objective lens 21f. As a result, an XY spot is formed on the light receiving surface of the image sensor 21i at a position according to the positional relationship (relative position) between the measurement head 14 and the cornea Ec in the XY direction. As a result, XY alignment detection can be performed to detect the relative position of the subject's eye E in the XY direction with respect to the measurement head 14.

[0041] The imaging element 21i captures an image of the XY spot formed on its light receiving surface, and outputs an imaging signal of the XY spot to the control device 16. As a result, under the control of the control device 16, the observed image of the anterior eye segment and the XY spot are superimposed and displayed on the monitor 15. Note that the monitor 15 also displays an alignment auxiliary mark.

[0042] The XY alignment index projection optical system 22 corresponds to the projection optical system of the present invention, and projects XY alignment index light, which corresponds to the light beam of the present invention, from the front onto the cornea Ec of the test eye E. This XY alignment index light is used for XY alignment of the measurement head 14 with respect to the test eye E. The XY alignment index light is also used to measure the intraocular pressure value of the test eye E. Hereinafter, the reflected light of the XY alignment index light by the cornea Ec will be simply abbreviated as "XY index reflected light."

[0043] The XY alignment index projection optical system 22 includes an XY alignment light source 22a, a condenser lens 22b, an aperture stop 22c, a pinhole plate 22d, a dichroic mirror 22e, and a collimator lens 22f (see FIG. 5). The XY alignment index projection optical system 22 shares the half mirror 21e with the anterior eye observation optical system 21.

[0044] The XY alignment light source 22a emits infrared light. The collimator lens 22f is disposed on the optical path of the XY alignment index projection optical system 22 so that its focal point coincides with the pinhole plate 22d. The infrared light emitted from the XY alignment light source 22a is focused by the condenser lens 22b, passes through the aperture stop 22c, and is guided to the hole of the pinhole plate 22d.

[0045] The infrared light passing through the hole of the pinhole plate 22d is reflected by the dichroic mirror 22e and guided to the collimator lens 22f, where it is collimated and then emitted from the collimator lens 22f to the half mirror 21e. This collimated infrared light is reflected by the half mirror 21e and travels along the optical axis O1 of the anterior eye observation optical system 21. As a result, the collimated infrared light passes through the half mirror 21g and the chamber window glass 21d, and then passes through the inside of the nozzle 21b, and enters the subject's eye E as XY alignment index light.

[0046] Although not shown, the XY alignment index light incident on the subject's eye E is reflected by the surface of the cornea Ec to form an XY spot. The aperture stop 22c is provided at a position conjugate with the corneal apex Ep of the cornea Ec with respect to the collimator lens 22f.

[0047] The fixation target projection optical system 23 projects a fixation target onto the subject's eye E. The fixation target projection optical system 23 has a fixation target light source 23a and a pinhole plate 23b (see FIG. 5). The fixation target projection optical system 23 also shares a dichroic mirror 22e and a collimator lens 22f with the XY alignment index projection optical system 22, and also shares a half mirror 21e with the anterior eye observation optical system 21.

[0048] The fixation target light source 23a emits visible light as fixation target light. This fixation target light is guided to the hole of the pinhole plate 23b, passes through the hole of the pinhole plate 23b and the dichroic mirror 22e, and is then emitted to the collimator lens 22f. The fixation target light is then converted into substantially parallel light by the collimator lens 22f and emitted toward the half mirror 21e, and is reflected by the half mirror 21e to travel along the optical axis O1 of the anterior eye observation optical system 21. As a result, the fixation target light passes through the half mirror 21g and the chamber window glass 21d, passes through the inside of the nozzle 21b, and reaches the subject's eye E. The subject can fix his or her gaze on the fixation target as a fixation target.

[0049] The applanation detection optical system 24 (see FIG. 5) corresponds to the light receiving optical system of the present invention, receives the XY index reflected light, and outputs an applanation signal (also called a corneal deformation signal) which is a light receiving signal indicating the amount of the XY index reflected light. The applanation detection optical system 24 has a lens 24a, a pinhole plate 24b, and a light receiving sensor 24c, and shares the half mirror 21g with the anterior eye observation optical system 21.

[0050] When the surface of the cornea Ec is flat, the lens 24a condenses the XY index reflected light onto the opening of the pinhole plate 24b, which is provided at the focal position of the lens 24a.

[0051] The light receiving sensor 24c is, for example, a photodiode that outputs an applanation signal according to the amount of light of the received XY index reflected light. The light receiving sensor 24c outputs the applanation signal to the control device 16.

[0052] The XY index reflected light passes through the inside of the nozzle 21b, passes through the chamber window glass 21d, and reaches the half mirror 21g. Then, a part of the XY index reflected light is reflected by the half mirror 21g, passes through the lens 24a, and is then incident on the pinhole plate 24b.

[0053] When the surface of the cornea Ec is in a flattened state (flat state) by the air blown from the nozzle 21b, the applanation detection optical system 24 allows the entire XY index reflected light traveling to the applanation detection optical system 24 to reach the light receiving sensor 24c through the pinhole plate 24b. When the cornea Ec is in a state other than the applanation state, the applanation detection optical system 24 allows the XY index reflected light to reach the light receiving sensor 24c while partially blocking it with the pinhole plate 24b. Therefore, the signal intensity of the detection signal of the XY index reflected light output from the applanation detection optical system 24 gradually increases as the surface of the cornea Ec changes from a convex state to an applanation state, and gradually decreases as the surface changes from the applanation state to a concave state.

[0054] The Z-alignment index projection optical system 25 (see FIG. 4) projects Z-alignment index light for Z alignment in the Z-axis direction from an oblique direction onto the cornea Ec. The Z-alignment index projection optical system 25 includes a Z-alignment light source 25a, a condenser lens 25b, an aperture stop 25c, a pinhole plate 25d, and a collimator lens 25e along the optical axis O2.

[0055] The Z-alignment light source 25a emits infrared light (for example, a wavelength of 860 nm). The aperture stop 25c is provided at a position conjugate with the corneal apex Ep with respect to the collimator lens 25e. The collimator lens 25e is disposed so as to focus on the hole of the pinhole plate 25d.

[0056] The infrared light emitted from the Z-alignment light source 25a is condensed by the condenser lens 25b, passes through the aperture stop 25c, and travels to the pinhole plate 25d. The infrared light that passes through the hole in the pinhole plate 25d is collimated by the collimator lens 25e, and then enters the subject's eye E as Z-alignment index light. The light is reflected by the cornea Ec to form a bright point image on the subject's eye E.

[0057] The Z alignment detection optical system 26 receives the reflected light of the Z alignment index light by the cornea Ec (hereinafter, abbreviated as Z index reflected light) and detects the positional relationship in the Z axis direction between the measurement head 14 and the cornea Ec. The Z alignment detection optical system 26 has an imaging lens 26a, a cylindrical lens 26b, and a light receiving sensor 26c along the optical axis O3.

[0058] The cylindrical lens 26b has power in the Y-axis direction. The light receiving sensor 26c is a sensor capable of detecting the receiving position of the Z index reflected light on its light receiving surface, and may be, for example, a line sensor or a PSD (Position Sensitive Detector).

[0059] The Z index reflected light is focused by the imaging lens 26a and then travels to the cylindrical lens 26b, where it is focused in the Y-axis direction to form a bright spot image on the light receiving sensor 26c.

[0060] The light receiving sensor 26c is in a positional relationship conjugate with the above-mentioned bright spot image formed on the subject's eye E by the Z alignment index projection optical system 25 with respect to the imaging lens 26a in the XZ plane. Also, the light receiving sensor 26c is in a positional relationship conjugate with the corneal apex Ep with respect to the imaging lens 26a and the cylindrical lens 26b in the YZ plane. That is, since the light receiving sensor 26c is in a conjugate relationship with the aperture stop 25c, even if the cornea Ec is displaced in the Y direction, the Z index reflected light on the surface of the cornea Ec efficiently enters the light receiving sensor 26c. Then, the light receiving sensor 26c outputs a detection signal of the Z index reflected light collected by the cylindrical lens 26b (hereinafter, referred to as a Z detection signal) to the control device 16. This Z detection signal indicates the relative position of the subject's eye E in the Z direction with respect to the measurement head 14, more specifically, the distance in the Z direction between the measurement head 14 and the subject's eye E (corneal apex Ep). This allows Z alignment detection.

[0061] The spray mechanism 34 (see FIG. 5) has, in addition to the nozzle 21b already described, a chamber 34a, a glass plate 34b, a pressure sensor 34c, a cylinder 34d, a communication pipe 34e, a piston 34f, and a solenoid 34g.

[0062] The nozzle 21b is attached to the chamber 34a via a transparent glass plate 34b. A chamber window glass 21d is provided in the chamber 34a at a position facing the nozzle 21b. A pressure sensor 34c is provided in the chamber 34a. The pressure sensor 34c outputs a pressure detection signal indicating the internal pressure of the chamber 34a (internal pressure) to the control device 16.

[0063] The cylinder 34d is connected to the chamber 34a via a communication pipe 34e. This allows the inside of the cylinder 34d to communicate with the inside of the chamber 34a via the communication pipe 34e. A piston 34f is movably provided inside the cylinder 34d. The cylinder 34d and the piston 34f form an air compression chamber.

[0064] The solenoid 34g is a known solenoid actuator that moves the piston 34f in the cylinder 34d. The solenoid 34g moves the piston 34f under the control of the control device 16 to compress the air in the cylinder 34d. As a result, air is blown from the nozzle 21b to the cornea Ec through the communication tube 34e and the chamber 34a.

[0065] In addition, in the blowing mechanism 34, the pressure sensor 34c detects the internal pressure of the chamber 34a, so that the pressure of the air blown from the nozzle 21b to the cornea Ec can be obtained.

[0066] Fig. 6 is a functional block diagram of the control device 16. As shown in Fig. 6, the control device 16 controls the overall operation of the non-contact tonometer 10. The control device 16 includes an arithmetic circuit configured with various processors and memories. The various processors include a central processing unit (CPU), a graphics processing unit (GPU), an application specific integrated circuit (ASIC), and a programmable logic device (e.g., simple programmable logic devices (SPLD), complex programmable logic devices (CPLD), and field programmable gate arrays (FPGA)). The various functions of the control device 16 may be realized by one processor, or may be realized by multiple processors of the same or different types.

[0067] The control device 16 is connected to the above-mentioned moving mechanism 13, the measurement head 14, the monitor 15, etc. This control device 16 controls the overall operation of the non-contact tonometer 10.

[0068] The control device 16 reads out and executes a control program (not shown) to function as a measurement control unit 40, an intraocular pressure value calculation unit 41, a model eye measurement control unit 42, a judgment unit 43, and a warning control unit 44. Note that what is described as a "unit" of the control device 16 may be a "circuit", a "device", or a "equipment". In other words, what is described as a "unit" may be composed of firmware, software, hardware, or a combination of these.

[0069] The measurement control unit 40 operates during intraocular pressure measurement of the subject's eye E to control auto-alignment of the measurement head 14 in the XYZ directions with respect to the subject's eye E, and the intraocular pressure measurement of the subject's eye E by the measurement head 14.

[0070] Specifically, the measurement control unit 40 controls the anterior eye observation optical system 21 and the XY alignment index projecting optical system 22 described above to perform XY alignment detection to detect the relative position of the subject's eye E in the XY direction with respect to the measurement head 14. The measurement control unit 40 also controls the Z alignment index projecting optical system 25 and the Z alignment detection optical system 26 to perform Z alignment detection to detect the relative position of the subject's eye E in the Z direction with respect to the measurement head 14. Note that the XY alignment detection and Z alignment detection of the non-contact tonometer 10 are well-known techniques, so a detailed description will be omitted here. Next, the measurement control unit 40 drives the moving mechanism 13 based on the XYZ alignment detection result to perform auto-alignment of the measurement head 14 with respect to the subject's eye E in the XYZ directions.

[0071] After the auto-alignment is completed, the measurement control unit 40 operates the spray mechanism 34 to perform a spraying process of spraying air onto the cornea Ec from the nozzle 21b of the spray mechanism 34. During the spraying process, the measurement control unit 40 continuously executes a process of projecting the XY alignment index light onto the cornea Ec by the XY alignment index projecting optical system 22, and a signal output process including receiving the XY index reflected light by the applanation detection optical system 24 and outputting an applanation signal.

[0072] The intraocular pressure value calculation unit 41 calculates the intraocular pressure value of the subject's eye E based on the applanation signal continuously output from the applanation detection optical system 24 and the detection result of the pressure sensor 34c. For example, the intraocular pressure value calculation unit 41 calculates the peak centroid position or maximum value of the applanation waveform W1 (see FIG. 9) based on the applanation signal output from the applanation detection optical system 24. Then, the intraocular pressure value calculation unit 41 calculates the intraocular pressure value of the subject's eye E by a known method based on the signal intensity (light amount) of the applanation signal corresponding to the peak centroid position or maximum value and the detection result (air pressure) of the pressure sensor 34c. Note that the method of calculating the intraocular pressure value of the subject's eye E is not limited to the above-mentioned method, and various known methods can be adopted.

[0073] The model eye measurement control unit 42, the judgment unit 43, and the warning control unit 44 operate when executing a "head condition check" to check whether the measurement head 14 is normal or not using the model eye 18. This head condition check is executed at any timing, for example, when the non-contact tonometer 10 is turned on, every time a certain period of time has elapsed, or before each intraocular pressure measurement of the subject eye E.

[0074] FIG. 7 is an explanatory diagram for explaining auto-alignment of the measuring head 14 with respect to the model eye 18 by the model eye measurement control unit 42. As shown in FIG.

[0075] As shown in Fig. 7 and the already described Fig. 6, when the head state is confirmed, the model eye measurement control unit 42 drives the moving mechanism 13 to perform auto-alignment of the measurement head 14 with respect to the model eye 18. In this auto-alignment, the measurement head 14 is moved to a model eye measurement position where the measurement head 14 can measure the intraocular pressure of the model eye 18. For example, the model eye measurement position is a position where the optical axis O1 (see Fig. 4) coincides (including approximately coincides) with the center of the model eye 18 in the XY directions, and a position where the distance between the tip of the nozzle 21b and the model eye 18 is adjusted to a predetermined working distance in the Z direction.

[0076] Here, the XYZ positions of the model eye 18 fixed to the forehead rest 12b are known. Furthermore, the model eye measurement control unit 42 can detect the XYZ positions of the measuring head 14 by a head position detection sensor (not shown). Therefore, the model eye measurement control unit 42 can perform auto-alignment by driving the moving mechanism 13 to move the measuring head 14 to the model eye measurement position, based on the known XYZ positions of the model eye 18 and the current XYZ position of the measuring head 14.

[0077] When auto-alignment of the measurement head 14 with respect to the model eye 18 is completed, the model eye measurement control unit 42 executes intraocular pressure measurement of the model eye 18 by the measurement head 14. Specifically, similar to the intraocular pressure measurement of the subject eye E by the measurement control unit 40 described above, the model eye measurement control unit 42 executes a blowing process of driving the blowing mechanism 34 to blow air from the nozzle 21b onto the model eye 18. In addition, while executing the blowing process, the model eye measurement control unit 42 continuously executes a process of projecting the XY alignment index light onto the model eye 18 by the XY alignment index projecting optical system 22, and a signal output process including receiving the XY index reflected light by the applanation detection optical system 24 and outputting an applanation signal.

[0078] Returning to Fig. 6, the judgment unit 43 judges whether the measurement head 14 is normal or not based on data obtained by intraocular pressure measurement of the model eye 18 using the measurement head 14, i.e., on time-series changes in the applanation signal (applanation waveform AS, see Fig. 9) continuously output from the applanation detection optical system 24. Here, "normal" means that no abnormality that would reduce the measurement accuracy of intraocular pressure measurement (such as adhesions to the nozzle 21b, dirt on the chamber window glass 21d, clogging of the nozzle 21b, etc.) has occurred.

[0079] Fig. 8 is an explanatory diagram showing an airflow A1 of air blown from a normal nozzle 21b having no attached matter onto the surface (corresponding to the cornea Ec) of the model eye 18. Fig. 9 is a graph showing an applanation waveform W1 showing a time series change in the applanation signal output from the applanation detection optical system 24 when air is blown onto the model eye 18 from the normal nozzle 21b, and an internal pressure waveform W2 showing a time series change in the internal pressure of the chamber 34a output from the pressure sensor 34c.

[0080] When the nozzle 21b is normal as shown in Fig. 8, an applanation waveform W1 and an internal pressure waveform W2 as shown in Fig. 9 are obtained. In this case, the applanation waveform W1 is capable of identifying a peak P1 indicating that the surface of the model eye 18 becomes applanated in the course of changing from a convex state to a concave state, and a peak P2 indicating that the surface of the model eye 18 becomes applanated in the course of changing from a concave state to a convex state.

[0081] Fig. 10 is an explanatory diagram showing airflow A1 blown from nozzle 21b to which minute deposits D that may affect measurement are attached onto the surface of model eye 18. Fig. 11 is a graph showing applanation waveform W1 showing the time series change in the applanation signal output from applanation detection optical system 24 when air is blown onto model eye 18 from nozzle 21b to which minute deposits D that may affect measurement are attached, and internal pressure waveform W2 showing the time series change in the internal pressure of chamber 34a output from pressure sensor 34c.

[0082] As shown in FIG. 10, when minute deposits D (hereinafter simply referred to as "minute deposits D") that may affect the measurement are attached to the nozzle 21b, disturbances occur in the airflow A1 of the air ejected from the nozzle 21b, and an applanation waveform W1 and an internal pressure waveform W2 as shown in FIG. 11 are obtained. Here, the internal pressure waveform W2 in this case does not show any noticeable difference from the normal waveform shown in FIG. 9. On the other hand, when disturbances occur in the airflow A1 of the air ejected from the nozzle 21b, the surface of the model eye 18 is not applanated sufficiently. Therefore, the applanation waveform W1 in this case has a different shape from the normal waveform shown in FIG. 9. As a result, it is difficult to detect the peaks P1 and P2 from the applanation waveform W1.

[0083] Therefore, the judgment unit 43 can judge whether or not microscopic deposits D are attached to the nozzle 21b, i.e., whether or not the measurement head 14 is normal, based on whether or not the applanation waveform W1 obtained by measuring the intraocular pressure of the model eye 18 is a normal waveform as shown in FIG. 9 (e.g., a waveform in which peaks P1 and P2 can be detected).

[0084] Similarly to the invention described in Patent Document 1, the determination unit 43 can detect the degree of dirt on the chamber window glass 21d, etc., based on the signal strength of the applanation waveform W1 (applanation signal) obtained by measuring the intraocular pressure of the model eye 18, i.e., the amount of received XY index reflected light. This allows the determination unit 43 to determine whether the measurement head 14 is normal or not, based on whether the degree of dirt on the chamber window glass 21d, etc. is equal to or less than a predetermined threshold.

[0085] Furthermore, the determination unit 43 can detect the occurrence of clogging of the nozzle 21b based on the internal pressure waveform W2 obtained by measuring the intraocular pressure of the model eye 18. This allows the determination unit 43 to determine whether or not the measurement head 14 is normal based on the presence or absence of clogging of the nozzle 21b.

[0086] Fig. 12 is a diagram showing an example of warning information 48 displayed on the monitor 15 by the warning control unit 44. As shown in Fig. 12 and the above-mentioned Fig. 6, the warning control unit 44 constitutes a warning unit of the present invention together with the monitor 15. When the determination unit 43 determines that the measuring head 14 is not normal, the warning control unit 44 notifies the examiner of the warning information 48 by displaying the warning information 48 on the monitor 15.

[0087] Although not shown in the figures, the warning control unit 44 may further display the cause of the abnormality in the measuring head 14 (adhesion of minute deposits D to the nozzle 21b, dirt on the chamber window glass 21d, clogging of the nozzle 21b, etc.) as the warning information 48. Furthermore, in addition to or instead of displaying the warning information 48 on the monitor 15, the warning control unit 44 may output the warning information 48 as sound from a speaker (not shown).

[0088] [Operation of the first embodiment] FIG. 13 is a flow chart showing the flow of a head state confirmation process of the measurement head 14 of the non-contact tonometer 10 having the above-mentioned configuration, in accordance with the operation method of an ophthalmic apparatus of the present invention.

[0089] As shown in Figure 13, when a predetermined timing is reached, such as when the non-contact tonometer 10 is turned on, or when the examiner inputs an operation to start head condition checking into an operation unit not shown, the control device 16 functions as a model eye measurement control unit 42, a judgment unit 43 and a warning control unit 44 and begins checking the head condition of the measurement head 14.

[0090] First, the model eye measurement control unit 42 drives the moving mechanism 13 when checking the head state, based on the XYZ positions of the model eye 18 and the XYZ positions of the measurement head 14, and executes auto-alignment of the measurement head 14 with respect to the model eye 18 fixed to the forehead rest 12b. This causes the measurement head 14 to automatically move to the model eye measurement position, making it possible to measure the intraocular pressure of the model eye 18 by the measurement head 14 (step S1). In this way, by fixing the model eye 18 to the head-facing surface 17 of the forehead rest 12b, it becomes unnecessary for the examiner to set the model eye 18 on the chin rest 12a or the like.

[0091] Next, the model eye measurement control unit 42 starts measuring the intraocular pressure of the model eye 18 by the measurement head 14 (step S2). Specifically, the model eye measurement control unit 42 controls the blowing mechanism 34, the XY alignment index projecting optical system 22, and the applanation detection optical system 24 to perform a process of blowing air onto the model eye 18 (step S3), a process of projecting the XY alignment index light onto the model eye 18 (step S4), and a process of outputting an applanation signal from the applanation detection optical system 24 (step S5). Steps S1 to S5 correspond to the model eye measurement steps of the present invention.

[0092] When the intraocular pressure measurement of the model eye 18 is completed, the determination unit 43 determines whether or not the measurement head 14 is normal based on data obtained by the intraocular pressure measurement of the model eye 18 using the measurement head 14 (step S6, which corresponds to the determination step of the present invention). For example, as shown in Figs. 8 to 11 described above, the determination unit 43 determines whether or not the measurement head 14 is normal by determining the presence or absence of adhesion of minute deposits D to the nozzle 21b based on the applanation waveform W1 obtained by the intraocular pressure measurement of the model eye 18.

[0093] When the determination unit 43 determines that the measurement head 14 is normal, the head condition check of the measurement head 14 is completed (YES in step S7). Here, in this embodiment, since the model eye 18 is fixed to the forehead rest 12b, the examiner does not need to remove the model eye 18 after the head condition check is completed.

[0094] On the other hand, if the determination unit 43 determines that the measurement head 14 is not normal (NO in step S7), the warning control unit 44 displays warning information 48 on the monitor 15 (step S8). This makes it possible to prompt the examiner to check the measurement head 14. As a result, the intraocular pressure measurement of the subject's eye E is prevented from being performed when there is an abnormality in the measurement head 14, thereby preventing a decrease in the measurement accuracy of the intraocular pressure measurement and preventing the subject from having to repeat the intraocular pressure measurement.

[0095] As described above, in the non-contact tonometer 10 of the first embodiment, the model eye 18 is fixed in a position different from the face placement area of ​​the face support part 12, so when checking the head condition of the measuring head 14, the examiner does not need to attach and detach the model eye 18. As a result, the head condition of the measuring head 14 can be checked easily and in a short time.

[0096] Furthermore, in the non-contact tonometer 10 of the first embodiment, the "presence or absence of adhesion of microscopic deposits D to the nozzle 21b," which cannot be determined from the internal pressure of the chamber 34a, can be determined based on the applanation waveform W1 (time-series change in the applanation signal) obtained by measuring the intraocular pressure of the model eye 18. As a result, the head state of the measuring head 14 can be checked more accurately.

[0097] [Second embodiment] Fig. 14 is an enlarged side view of the forehead rest 12b and model eye 18 of the non-contact tonometer 10 of the second embodiment. In the non-contact tonometer 10 of the first embodiment, the model eye 18 is fixed to the forehead rest 12b located near the subject, so there is a risk that the subject may accidentally touch the model eye 18. Therefore, as shown in Fig. 14, in the non-contact tonometer 10 of the second embodiment, a cover 50 that covers the model eye 18 except when the head state of the measurement head 14 is being checked, i.e., when the model eye 18 is not being used, is provided on the head-facing surface 17 of the forehead rest 12b.

[0098] The non-contact tonometer 10 of the second embodiment has basically the same configuration as the non-contact tonometer 10 of the first embodiment, except that the forehead rest 12b is provided with a cover 50. Therefore, parts that are the same in function or configuration as those of the first embodiment are given the same reference numerals and their description will be omitted.

[0099] As shown in Fig. 14, cover 50 has a rotation axis 50a that is parallel to the X direction when viewed from measurement head 14. This rotation axis 50a is fixed to a position in the head-facing surface 17 of forehead rest 12b above model eye 18 in the Y direction. Cover 50 is provided so as to be freely rotatable about rotation axis 50a between a protection position (see reference symbol XIVA in Fig. 14) in which it covers model eye 18 and an exposure position (see reference symbol XIVB in Fig. 14) in which it rotates upward in the Y direction from the protection position to expose model eye 18.

[0100] The rotation of the cover 50 from the protection position to the exposure position and the rotation of the cover 50 from the exposure position to the protection position are automatically performed by utilizing the movement of the measuring head 14 by the movement mechanism 13.

[0101] Fig. 15 is an explanatory diagram for explaining the automatic rotation of the cover 50 from the protection position to the exposure position when checking the head state of the measurement head 14. As shown in Fig. 15, the rotation of the cover 50 from the protection position to the exposure position is performed by being pressed by the measurement head 14 which is moved by the movement mechanism 13 toward the model eye measurement position in auto-alignment when checking the head state.

[0102] Specifically, the movement path of the measurement head 14 during auto-alignment is adjusted, and while the model eye measurement control unit 42 drives the movement mechanism 13 to move the measurement head 14 to the model eye measurement position, the measurement head 14 is brought into contact with the cover 50 from the lower side in the Y direction of the cover 50, as shown by arrow Y1 in the figure (see symbols XVA and XVB in Figure 15).

[0103] Next, the model eye measurement control unit 42 drives the moving mechanism 13 to move the measuring head 14 upward in the Y direction (see arrow Y1) toward the model eye measurement position, so that the measuring head 14 presses the cover 50 at the protection position upward in the Y direction (see symbol XVC in FIG. 15). This pressing causes the cover 50 to rotate from the protection position toward the upward side in the Y direction around the rotation axis 50a. Then, when the measuring head 14 reaches the model eye measurement position, the cover 50 is rotated to the exposure position. This makes it possible to automatically rotate the cover 50 from the protection position to the exposure position without providing a rotation mechanism for rotating the cover 50. Then, the cover 50 is kept at the exposure position by the measuring head 14 stopped at the model eye measurement position.

[0104] Fig. 16 is an explanatory diagram for explaining the automatic rotation of the cover 50 from the exposed position to the protected position after the head state of the measuring head 14 is confirmed. As shown in Fig. 16, when the head state confirmation of the measuring head 14 is completed, the model eye measurement control unit 42 drives the moving mechanism 13 to retreat the measuring head 14 from the model eye measurement position downward in the Y direction (see arrow Y2 in the figure). With this retreat of the measuring head 14, the cover 50 also rotates downward in the Y direction from the protected position due to its own weight (see symbols XVIA and XVIB in Fig. 15).

[0105] Next, the model eye measurement control unit 42 drives the moving mechanism 13 to move the measurement head 14 downward in the Y direction, thereby releasing the contact between the measurement head 14 and the cover 50, and the cover 50 rotates to the exposed position. This makes it possible to automatically rotate the cover 50 from the exposed position to the protected position without providing a rotation mechanism for the cover 50.

[0106] Incidentally, an elastic member such as a torsion spring may be provided on the rotating shaft 50a, so that the cover 50 can be rotated from the exposed position to the protected position by the restoring force of the elastic member after the measuring head 14 is retracted.

[0107] As described above, in the non-contact tonometer 10 of the second embodiment, by providing the cover 50 that can rotate between the protected position and the exposed position on the forehead rest 12b, the model eye 18 can be covered by the cover 50 rotated to the protected position when the model eye 18 is not in use. As a result, the subject is prevented from accidentally touching the model eye 18.

[0108] Furthermore, in the non-contact tonometer 10 of the second embodiment, the measurement head 14, which is moved by the movement mechanism 13 toward the model eye measurement position by auto-alignment, is used to rotate the cover 50 from the protected position to the exposed position, and conversely, the measurement head 14 is retracted from the model eye measurement position to rotate the cover 50 from the exposed position to the protected position. As a result, the cover 50 can be automatically rotated from the protected position to the exposed position and from the exposed position to the protected position without providing a rotation mechanism for the cover 50. This reduces the number of parts in the non-contact tonometer 10, thereby achieving low costs.

[0109] Fig. 17 is an explanatory diagram for explaining a modified example of the non-contact tonometer 10 of the second embodiment. In the above-mentioned second embodiment, the measurement head 14 is used to rotate the cover 50, but as shown in Fig. 17, the cover 50 may be rotated between a protected position (see symbol XVIIA in Fig. 17) and an exposed position (see symbol XVIIB in Fig. 17) using a cover rotation mechanism 52 composed of a motor, gears, etc.

[0110] When checking the head condition of the measuring head 14, the model eye measurement control unit 42 drives the cover rotation mechanism 52 to rotate the cover 50 to the exposed position before the moving mechanism 13 moves the measuring head 14 to the model eye measurement position. After completing the head condition check, the model eye measurement control unit 42 drives the cover rotation mechanism 52 to rotate the cover 50 to the protected position after the moving mechanism 13 retracts the measuring head 14 from the model eye measurement position.

[0111] In the second embodiment and its modified example, the cover 50 is provided on the face support unit 12 so as to be rotatable around the rotation axis 50a between the protection position and the exposure position, but the orientation of the rotation axis 50a is not particularly limited, and may be parallel to the Z direction or parallel to the Y direction. Furthermore, the cover 50 does not need to be provided rotatable with respect to the face support unit 12 as long as it is possible to switch between protection and exposure of the model eye 18, and for example, the cover 50 may be provided so as to be openable and closable in any of the X, Y, and Z directions. In other words, the structure of the cover 50 and the method of attachment to the face support unit 12 are not particularly limited as long as the cover 50 is displaceable (including deformable) between the protection position and the exposure position.

[0112] [Third embodiment] Fig. 18 is a side view of a refractometer 10A of the third embodiment. In each of the above embodiments, the non-contact tonometer 10 has been described as an example of the ophthalmic device of the present invention, but the present invention can also be applied to a refractometer 10A that measures the ocular refractive power as an ocular characteristic of the subject's eye E as shown in Fig. 18.

[0113] The refractometer 10A has basically the same configuration as the non-contact tonometer 10 of each of the above-mentioned embodiments, except that it includes a measurement head 14A and a model eye 18A that are different from those of the non-contact tonometer 10. For this reason, the same reference numerals are used to designate the same components in function or configuration as those of the above-mentioned embodiments, and the description thereof will be omitted.

[0114] The measurement head 14A has a function of using various optical systems and sensors to measure the ocular refractive power of the subject's eye E. Note that the specific configuration of the measurement head 14A for measuring ocular refractive power is a publicly known technique (see, for example, JP 2015-112437 A), and therefore will not be described here.

[0115] Similar to the model eye 18 in each of the above-described embodiments, the model eye 18A is fixed to the head-facing surface 17 of the forehead rest 12b. Note that the model eye 18A may be fixed to a position other than the head-facing surface 17 of the forehead rest 12b as long as it is a "position different from the face arrangement area" of the face support part 12.

[0116] Fig. 19 is a side view of model eye 18A of the third embodiment. As shown in Fig. 19 and the above-mentioned Fig. 18, model eye 18A is made of glass with a hemispherical tip. In addition, a reflective paint film 54 is formed on the bottom surface of model eye 18A. Note that the shape and structure of model eye 18A are not particularly limited as long as it can be used for measuring eye refractive power with refractometer 10A.

[0117] Although not shown, the control device 16 of the third embodiment has basically the same configuration as the control device 16 of each of the above embodiments, except that it functions as a known eye refractive power calculation unit instead of the intraocular pressure value calculation unit 41.

[0118] When checking the head status of the measuring head 14A, the model eye measurement control unit 42 of the third embodiment executes a movement process to drive the moving mechanism 13 to move the measuring head 14A to the model eye measurement position, and then executes a measurement process of the eye refractive power of the model eye 18A using the measuring head 14A at the model eye measurement position.

[0119] The judgment unit 43 of the third embodiment judges whether the measurement head 14A is normal or not based on data obtained by the measurement of the ocular refractive power of the model eye 18A by the measurement head 14A, i.e., the measured value of the ocular refractive power of the model eye 18A. Specifically, the judgment unit 43 compares the measured value of the ocular refractive power of the model eye 18A with the known ocular refractive power of the model eye 18A, and judges the measurement head 14A to be normal if the difference between the two is equal to or smaller than a threshold value, and conversely, judges the measurement head 14A to be abnormal if the difference between the two is greater than the threshold value.

[0120] When the determination unit 43 determines that the measuring head 14A is not normal, the warning control unit 44 of the third embodiment displays warning information 48 indicating that fact on the monitor 15. The warning control unit 44 may output the warning information 48 as sound from a speaker (not shown).

[0121] As described above, in the refractometer 10A of the third embodiment as well, by fixing the model eye 18A at a position different from the face placement area of ​​the face support part 12, the same effects as those described in the above embodiments can be obtained.

[0122] [others] In each of the above embodiments, a non-contact tonometer 10 and a refractometer 10A have been used as examples of the ophthalmic device of the present invention, but the present invention can be applied to various ophthalmic devices (including multifunction devices) that acquire various ocular characteristics of the subject eye E, such as a contact tonometer, a keratometer, an autorefractometer, and a corneal endothelial cell inspection device. [Explanation of symbols]

[0123] 10. Non-contact tonometer 10A…Refractometer 11...Bass 12…Face support part 12a…Chin rest 12b…Forehead rest 12c…post 13...Movement mechanism 14…Measuring head 14A…Measuring head 15…Monitor 16...Control device 17…Head facing surface 18...Model eyes 18A…Model eye 21...Anterior segment observation optical system 21a...Anterior segment illumination light source 21b…Nozzle 21c…Anterior window glass 21d…Chamber window glass 21e…Half mirror 21f…Objective lens 21g…Half mirror 21i…Image sensor 22...XY alignment target projection optical system 22a…Light source for XY alignment 22b...Condenser lens 22c…Aperture diaphragm 22d…Pinhole plate 22e…Dichroic mirror 22f...Collimator lens 23…Fixation target projection optical system 23a...Fixation target light source 23b…Pinhole plate 24...Applanation detection optical system 24a…Lens 24b…Pinhole plate 24c...Light receiving sensor 25...Z alignment index projection optical system 25a…Z alignment light source 25b…Condenser lens 25c…Aperture 25d…Pinhole plate 25e…Collimator lens 26…Z alignment detection optical system 26a…Imaging lens 26b…Cylindrical lens 26c...Light receiving sensor 34...Spray mechanism 34a…Chamber room 34b…Glass plate 34c...Pressure sensor 34d…Cylinder 34e…Communication pipe 34f...Piston 34g…Solenoid 40...Measurement control section 41...Intraocular pressure value calculation unit 42...Model eye measurement control unit 43...Judgment section 44...Warning control unit 48...Warning information 50…Cover 50a…Rotating shaft 52...Cover rotation mechanism 54...Reflective paint film A1…Air flow AS…Applanation waveform D: Microscopic deposits E…Examined eye Ec…cornea Ep…corneal apex O1…Optical axis O2…optical axis O3…Optical axis P1…Peak P2…Peak W1…Applanation waveform W2…Internal pressure waveform

Claims

1. A face support portion that supports the face of the subject; A measurement head for measuring ocular characteristics of a subject's eye; a moving mechanism for moving the measuring head; a model eye imitating a human eye, the model eye being fixed to a position of the face support unit different from a face arrangement area in which the face of the subject is arranged; a model eye measurement control unit that drives the moving mechanism to move the measurement head to a model eye measurement position where the ocular characteristics of the model eye can be measured, and causes the measurement head to measure the ocular characteristics of the model eye at the model eye measurement position; a determination unit that determines whether the measurement head is normal or not based on data obtained by measuring the ocular characteristics of the model eye using the measurement head; An ophthalmic apparatus comprising:

2. The ophthalmic apparatus according to claim 1 , wherein the model eye is integrated with the face support portion.

3. The face support portion includes a forehead support portion that contacts the forehead of the subject, 3. The ophthalmologic apparatus according to claim 2, wherein the model eye is fixed to a head-facing surface of the forehead rest portion that faces the measurement head.

4. The ophthalmologic apparatus according to claim 1 , wherein the face support portion includes a cover that is displaceable between a protection position that covers the model eye and an exposure position that exposes the model eye.

5. the cover is provided so as to be displaceable between the protected position and the exposed position rotated upward from the protected position about a rotation axis parallel to a left-right direction when viewed from the measuring head, While the model eye measurement control unit drives the moving mechanism to move the measurement head to the model eye measurement position, the measurement head presses the cover in the protection position upward to displace the cover to the exposed position, The ophthalmologic apparatus according to claim 4 , wherein the cover is displaced from the exposed position to the protected position when the model eye measurement control unit drives the moving mechanism to retract the measurement head from the model eye measurement position.

6. The ophthalmic apparatus according to claim 4 , further comprising a cover rotation mechanism for displacing the cover between the protection position and the exposure position.

7. The ophthalmologic apparatus according to claim 1 , further comprising a warning unit that issues warning information when the determining unit determines that the measuring head does not operate normally.

8. the measurement head is configured to non-contact measure an intraocular pressure value of the subject's eye as an ocular characteristic of the subject's eye, the measurement head includes at least a blowing mechanism that blows air from a nozzle onto the cornea of ​​the subject's eye, a projection optical system that projects a light beam onto the cornea, and a light receiving optical system that receives reflected light of the light beam reflected by the cornea and outputs a light receiving signal; The model eye measurement control unit, a moving process of driving the moving mechanism to move the measurement head to the model eye measurement position; a blowing process of driving the blowing mechanism to blow the air from the nozzle to the model eye when the moving process is completed; a projection process for projecting the light beam from the projection optical system onto the model eye while the spraying process is being performed; a signal output process for outputting, from the light receiving optical system, the light receiving signal obtained by receiving the reflected light of the light beam reflected by the model eye while the spraying process is being performed; Run The ophthalmic device according to any one of claims 1 to 6, wherein the determination unit determines whether or not the measurement head is normal by determining whether or not there is any adhesion to the nozzle based on a time series change in the light receiving signal output from the light receiving optical system.

9. a measuring head for measuring an ocular refractive power of the subject's eye as an ocular characteristic of the subject's eye, The model eye measurement control unit, a moving process of driving the moving mechanism to move the measurement head to the model eye measurement position; a measurement process for performing measurement of an ocular refractive power of the model eye by the measuring head when the moving process is completed; Run 7. The ophthalmic device according to claim 1, wherein the determination unit determines whether the measurement head is normal or not based on a measurement result of the ocular refractive power of the model eye by the measurement head and a measurement result of a known ocular refractive power of the model eye.

10. 1. A method for operating an ophthalmologic apparatus including a face support unit for supporting a face of a subject, a measurement head for measuring ocular characteristics of a subject's eye, and a moving mechanism for moving the measurement head, comprising the steps of: a model eye measurement step of driving the moving mechanism to move the measurement head to a model eye measurement position where eye characteristics of a model eye imitating a human eye fixed at a position of the face support unit different from a face placement area where the face of the subject is placed can be measured, and measuring the eye characteristics of the model eye by the measurement head at the model eye measurement position; a determination step of determining whether or not the measuring head is normal based on data obtained by measuring the ocular characteristics of the model eye by the measuring head; A method for operating an ophthalmic device comprising the steps of:

Images