Ophthalmologic apparatus and non-contact type sensor operation confirmation method

Abstract

To provide an ophthalmologic apparatus and a non-contact type sensor operation confirmation method which can execute operation confirmation of a non-contact type sensor at a low cost without installing a new installation space.SOLUTION: An ophthalmologic apparatus comprises: an eye characteristic acquisition unit (non-contact type tonometer 14B); a drive mechanism 13 which can move at least the eye characteristic acquisition unit in the front-rear direction; an alignment detection unit (detection control unit 42b); an alignment execution unit 42c which performs alignment of the eye characteristic acquisition unit with respect to a subject eye on the basis of the detection result of the alignment detection unit; a non-contact type sensor (capacitance type sensor 36) which can detect the approach of the eye characteristic acquisition unit to the face of a subject in a non-contact manner; a confirmation unit 45a which confirms whether or not the alignment detection unit can detect a distance in the front-rear direction between the eye characteristic acquisition unit and a target object (subject eye E); and a determination unit 45c which determines whether or not the non-contact type sensor is normally operated on the basis of a detection value of the non-contact type sensor when the confirmation unit confirms that the distance can be detected.SELECTED DRAWING: Figure 8

Description

Technical Field

[0001] The present invention relates to an ophthalmic apparatus provided with a non-contact sensor and a method for confirming the operation of the non-contact sensor.

Background Art

[0002] As one of the ophthalmic apparatuses for acquiring (measuring, photographing, observing, etc.) the eye characteristics of the eye to be examined, a non-contact tonometer that measures the intraocular pressure of the eye to be examined without contact or a combined device (combined ophthalmic apparatus) equipped with this non-contact tonometer is known (see Patent Document 1 and Patent Document 2). The non-contact tonometer measures the intraocular pressure value of the eye to be examined without contacting the cornea by deforming the cornea by blowing air from a nozzle toward the cornea of the eye to be examined and detecting the deformed state. Before starting the intraocular pressure measurement of the eye to be examined by this non-contact tonometer, alignment of the measurement head with respect to the eye to be examined is performed. At this time, it is necessary to prevent contact between the nozzle, the eye to be examined, and the face of the subject.

[0003] Patent Document 3 describes a non-contact tonometer equipped with a sensor (non-contact sensor) capable of detecting the approach of the measurement head to the face (eye to be examined) of the subject. The non-contact tonometer described in Patent Document 3 stops alignment when the sensor detects the approach of the measurement head to the face of the subject during alignment. In order to stop alignment when the measurement head approaches the face of the subject in this way, the sensor needs to be operating correctly.

[0004] Therefore, the non-contact tonometer described in Patent Document 3 is provided with a pseudo reaction part (such as a capacitor) capable of reproducing a proximity state in which the face of the subject is in a state of being sufficiently close to the sensor (less than the operating distance of the non-contact tonometer). Then, the non-contact tonometer described in Patent Document 3 acquires a detection value (detection signal) from the sensor while reproducing a proximity state from the pseudo reaction part, and performs an operation confirmation as to whether the sensor operates normally based on this detection signal.

Prior Art Documents

Patent Documents

[0005] [Patent Document 1] Japanese Patent Publication No. 2015-112437 [Patent Document 2] Japanese Patent Publication No. 2008-099968 [Patent Document 3] Japanese Patent Publication No. 2021-153907 [Overview of the project] [Problems that the invention aims to solve]

[0006] Incidentally, the non-contact tonometer described in Patent Document 3 requires a separate simulated reaction unit to verify the operation of the sensor. Therefore, the non-contact tonometer described in Patent Document 3 presents problems such as increased costs and the need to secure space for the simulated reaction unit.

[0007] This invention has been made in view of these circumstances, and aims to provide an ophthalmic device and a method for verifying the operation of a non-contact sensor at low cost without requiring new installation space. [Means for solving the problem]

[0008] An ophthalmic apparatus for achieving the object of the present invention includes: an eye characteristic acquisition unit for acquiring the eye characteristics of the eye under examination; a drive mechanism for relatively moving the eye characteristic acquisition unit relative to the eye under examination, wherein the drive mechanism is capable of moving at least the eye characteristic acquisition unit forward towards the eye under examination and backward away from the eye under examination along the anterior-posterior direction; an alignment detection unit for detecting the relative position of the eye under examination with respect to the eye characteristic acquisition unit, wherein the alignment detection unit has the function of detecting at least the anterior-posterior distance between the eye characteristic acquisition unit and the eye under examination; and an ophthalmic apparatus for acquiring eye characteristics of the eye under examination by automatically driving the drive mechanism or driving the drive mechanism in response to manual movement operation based on the detection result of the alignment detection unit. The system comprises: an alignment execution unit that performs alignment of the unit; a non-contact sensor provided in the eye characteristic acquisition unit that is capable of detecting the approach of the eye characteristic acquisition unit to the subject's face without contact, and which has a second detection range that encompasses the first detection range of the alignment detection unit in the front-to-back direction; a confirmation unit that checks whether the alignment detection unit can detect the distance in the front-to-back direction between the eye characteristic acquisition unit and a target object within the first detection range; and a determination unit that, when the confirmation unit confirms that the alignment detection unit can detect the distance in the front-to-back direction, determines whether the non-contact sensor is operating normally based on the detection value of the non-contact sensor.

[0009] This ophthalmic device allows for the verification of the operation of non-contact sensors using the existing alignment detection unit of the ophthalmic device.

[0010] In another embodiment of the present invention, the ophthalmic device determines whether the non-contact sensor is functioning normally based on whether the detected value of the non-contact sensor is equal to or greater than a determination threshold. This allows for verification of the operation of the non-contact sensor.

[0011] In another aspect of the present invention, an ophthalmic device is provided that, if the alignment detection unit does not confirm that the anterior-posterior distance can be detected by the confirmation unit, moves at least one of the eye characteristic acquisition unit and the target object to adjust the position of the target object within a first detection range. This makes it possible to verify the operation of a non-contact sensor using an existing alignment detection unit.

[0012] In another aspect of the present invention, the ophthalmic device confirms whether or not it can detect the distance in the anterior-posterior direction with respect to the eye under examination as the target object. This allows for verification of the operation of the non-contact sensor before acquiring the ocular characteristics of the eye under examination.

[0013] In another aspect of the present invention, the ophthalmic device confirms whether it can detect the distance in the anterior-posterior direction from a model eye, which mimics the eye of the person being examined, to the target object. This allows for verification of the operation of a non-contact sensor without using the eye of the person being examined (human eye), and prevents a part of the eye characteristic acquisition unit from coming into contact with the face of the person being examined during this verification.

[0014] In another aspect of the present invention, the ophthalmic device includes a face support portion that supports the face of a subject, and further includes a chin support portion that receives the subject's chin and a forehead support portion that contacts the subject's forehead, wherein the chin support portion supports a model eye and a conductive material connected to ground. This allows for verification of the operation of a non-contact sensor without using a subject's eye (human eye).

[0015] In another embodiment of the present invention, an ophthalmic apparatus is provided that includes a notification unit that notifies warning information when a determination unit determines that a non-contact sensor is not functioning properly, or when the detected value of the non-contact sensor exceeds a threshold during alignment. This allows the examiner to be notified of the warning information.

[0016] In another aspect of the present invention, an ophthalmic apparatus is provided with a hazard avoidance action control unit that controls the drive mechanism to perform a hazard avoidance action when the detected value of a non-contact sensor exceeds a threshold during alignment. This ensures that the eye characteristic acquisition unit does not come into contact with the subject's face.

[0017] A non-contact sensor operation confirmation method for achieving the object of the present invention includes: an eye characteristic acquisition unit for acquiring the eye characteristics of the eye under examination; a drive mechanism for relatively moving the eye characteristic acquisition unit relative to the eye under examination, and the drive mechanism being capable of moving at least the eye characteristic acquisition unit forward towards the eye under examination and backward away from the eye under examination along the front-rear direction; an alignment detection unit for detecting the relative position of the eye under examination with respect to the eye characteristic acquisition unit, and the alignment detection unit having the function of detecting at least the distance in the front-rear direction between the eye characteristic acquisition unit and the eye under examination; and an alignment detection unit that automatically drives the drive mechanism or drives the drive mechanism in response to a manual movement operation based on the detection result of the alignment detection unit to perform alignment of the eye characteristic acquisition unit with respect to the eye under examination. A method for verifying the operation of a non-contact sensor in an ophthalmic device comprising an alignment execution unit and an eye characteristic acquisition unit, the non-contact sensor being provided in the eye characteristic acquisition unit and capable of detecting the approach of the eye characteristic acquisition unit to the face of a subject without contact, and having a second detection range that encompasses a first detection range of the alignment detection unit in the front-to-back direction, the method comprising: a verification step of verifying whether the alignment detection unit can detect the distance in the front-to-back direction between the eye characteristic acquisition unit and a target object within the first detection range; and a determination step of determining whether the non-contact sensor is operating normally based on the detection value of the non-contact sensor, if the alignment detection unit is confirmed to be able to detect the distance in the front-to-back direction in the verification step. [Effects of the Invention]

[0018] This invention enables low-cost operational verification of non-contact sensors without requiring additional installation space. [Brief explanation of the drawing]

[0019] [Figure 1] This is a side view of the ophthalmic device according to the first embodiment. [Figure 2] This is a schematic top view of the multiple types of optical systems inside a non-contact tonometer, viewed from above (Y direction). [Figure 3] This is a schematic side view of the multiple types of optical systems inside a non-contact tonometer, viewed from the side (X direction). [Figure 4]This is a perspective view of the spraying mechanism of the non-contact tonometer as seen from the subject side. [Figure 5] This is an enlarged front view of the electrodes of the capacitance-type sensor in FIG. 4. [Figure 6] This is an explanatory diagram for explaining the directivity of the capacitance-type sensor. [Figure 7] This is a functional block diagram of the control device. [Figure 8] This is an explanatory diagram for explaining a specific method for confirming the operation of the capacitance-type sensor of the first embodiment. [Figure 9] This is an explanatory diagram showing an example of notification of warning information by the notification control unit. [Figure 10] This is a flowchart showing the flow of the refraction measurement and intraocular pressure measurement of the subject eye by the ophthalmic device of the first embodiment. [Figure 11] This is a flowchart showing the flow of the operation confirmation process of the capacitance-type sensor. [Figure 12] This is an explanatory diagram for explaining a method for confirming the operation of the capacitance-type sensor by the ophthalmic device of the second embodiment.

Mode for Carrying Out the Invention

[0020] [First Embodiment] FIG. 1 is a side view of the ophthalmic device 10 of the first embodiment. As shown in FIG. 1, it is a composite device capable of measuring the intraocular pressure value, refractive power, corneal curvature, etc. of the left and right subject eyes E of the subject. This ophthalmic device 10 includes a base 11, a face support portion 12, a drive mechanism 13, a measurement head 14, a monitor 15, and a control device 16.

[0021] Among the mutually orthogonal XYZ directions (three-axis directions) in the figure, the Y direction is the vertical direction, the Z direction is the front-rear direction (also referred to as the operating distance direction) in which the subject (subject eye E) approaches or moves away, and the X direction is the left-right direction perpendicular to both the vertical direction and the front-rear direction. Also, among the Z directions (front-rear direction), the side approaching the subject eye E (subject) is referred to as the Z direction front side, and the side moving away from the subject eye E (subject) is referred to as the Z direction rear side.

[0022] A face support section 12 and a drive mechanism 13 are provided on the base 11, extending from the front side in the Z direction to the rear side in the Z direction. The base 11 supports the measuring head 14 so that it can move in the XYZ directions via the drive mechanism 13.

[0023] The face support section 12 is fixed to the base 11. This face support section 12 includes a chin rest section 12a that receives the subject's chin and a forehead rest section 12b that comes into contact with the subject's forehead, and supports the subject's face.

[0024] The drive mechanism 13 is composed of an actuator (not shown), such as a motor. This drive mechanism 13 moves the measuring head 14 in the XYZ direction relative to the base 11. This allows the measuring head 14 to be moved relative to the eye E being examined in the XYZ direction.

[0025] The measuring head 14 is equipped with an autorefractor / keratometer 14A and a non-contact tonometer 14B, which corresponds to the eye characteristic acquisition unit of the present invention. In this embodiment, the non-contact tonometer 14B is provided on the side of the autorefractor / keratometer 14A that is above it in the Y direction.

[0026] The autorefractometer 14A performs refractometer-keratometer measurements to determine the refractive power and corneal curvature of the eye E under examination using various optical systems and sensors. The autorefractometer 14A is equipped with various optical systems used for anterior segment observation, alignment detection, alignment, and refractometer-keratometer measurements of the eye E under examination, although these are not shown in the figures. The specific configuration of the autorefractometer 14A is based on publicly known technology (see, for example, Patent Document 1 above), so a detailed explanation is omitted here.

[0027] The non-contact tonometer 14B measures the intraocular pressure of the eye E without contact by deforming the cornea Ec by blowing air from a nozzle 21b toward the cornea Ec of the eye E and detecting the state of deformation. The working distance of this non-contact tonometer 14B is shorter than that of the autorefractor keratometer 14A.

[0028] In this embodiment, the intraocular pressure of the eye E being examined is measured using the non-contact tonometer 14B after the refractometer measurement using the autorefractometer 14A. Therefore, the drive mechanism 13 performs a rough alignment, which includes moving the measuring head 14 downward in the Y direction and moving the measuring head 14 forward in the Z direction, after the refractometer measurement using the autorefractometer 14A is completed and before the intraocular pressure measurement using the non-contact tonometer 14B.

[0029] The monitor 15 is a touch panel monitor mounted on the back of the measurement head 14. Under the control of the control device 16 (described later), the monitor 15 displays various images, including the captured image (observation image) of the eye E taken by the autorefractometer 14A or non-contact tonometer 14B, the measurement results of the eye characteristics of the eye E (refractive power, corneal curvature, and intraocular pressure), and an operation menu screen for performing various operations. These operations include manual movement of the measurement head 14 in the XYZ directions. The monitor 15 also displays various warning information under the control of the control device 16 (see Figure 9).

[0030] <Non-contact tonometer 14B> Figure 2 is a schematic top view of the multiple types of optical systems inside the non-contact tonometer 14B, viewed from above (Y direction), and Figure 3 is a schematic side view of the multiple types of optical systems inside the non-contact tonometer 14B, viewed from the side (X direction).

[0031] As shown in Figures 2 and 3, the non-contact tonometer 14B comprises an anterior segment observation optical system 21, an XY alignment index projection optical system 22, a fixation target projection optical system 23, an applanation detection optical system 24, a Z alignment index projection optical system 25, a Z alignment detection optical system 26, and a spraying mechanism 34.

[0032] The anterior segment observation optical system 21 is used for observing the anterior segment of the eye E under examination and for XY alignment of the non-contact tonometer 14B in the XY direction relative to the eye E under examination. This anterior segment observation optical system 21 is equipped with an anterior segment illumination light source 21a (see Figure 2). On the optical axis O1 (the principal optical axis of the non-contact tonometer 14B) of the anterior segment observation optical system 21, there is an air blowing nozzle 21b, an anterior segment window glass 21c (see Figure 3) 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.

[0033] Multiple anterior segment illumination light sources 21a are provided around the anterior segment window glass 21c to directly illuminate the anterior segment of the eye E under examination.

[0034] The nozzle 21b is connected to the chamber 34a (see Figure 3) of the spraying mechanism 34 and blows air onto the anterior segment (cornea Ec) of the eye E under examination.

[0035] The image of the anterior segment of the eye E under examination (image light from the anterior segment) passes outside the nozzle 21b, through the anterior segment window glass 21c, the glass plate 34b (described later), the chamber window glass 21d, the half mirror 21g, and the half mirror 21e, and is formed on the light-receiving surface of the image sensor 21i by the objective lens 21f.

[0036] The image sensor 21i is, for example, a CCD (Charge Coupled Device) or CMOS (complementary metal oxide semiconductor) type image sensor. This image sensor 21i captures an image of the anterior segment of the eye that is incident on its light-receiving surface, generates an imaging signal, and outputs this imaging signal to the control device 16. As a result, under the control of the control device 16, the observed image of the anterior segment of the eye E under examination, based on the imaging signal output from the image sensor 21i, is displayed on the monitor 15.

[0037] Furthermore, the anterior segment observation optical system 21 guides the reflected light from the cornea Ec of the XY alignment index light projected onto the eye E by the XY alignment index projection optical system 22 (described later) 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 onto the light-receiving surface of the image sensor 21i by the objective lens 21f. As a result, XY spots are formed on the light-receiving surface of the image sensor 21i at positions corresponding to the XY positional relationship (relative position) between the non-contact tonometer 14B and the cornea Ec. This enables XY alignment detection, which detects the XY relative position of the eye E with respect to the non-contact tonometer 14B. Therefore, the anterior segment observation optical system 21 and the XY alignment index projection optical system 22 function as part of the alignment detection unit of the present invention.

[0038] The image sensor 21i captures an XY spot formed on its light-receiving surface and outputs the imaging signal of this XY spot to the control device 16. As a result, under the control of the control device 16, the observed image of the anterior segment and the XY spot are superimposed on the monitor 15. Alignment assist marks are also displayed on the monitor 15.

[0039] The XY alignment index projection optical system 22 projects XY alignment index light onto the cornea Ec of the eye under examination E from the front. This XY alignment index light is used for XY alignment of the non-contact tonometer 14B with respect to the anterior segment of the eye under examination E. The XY alignment index light is also used to measure the intraocular pressure value of the eye under examination E. Hereinafter, the reflected light of the XY alignment index light from the cornea Ec will be simply referred to as "XY index reflected light".

[0040] The XY alignment indicator projection optical system 22 includes an XY alignment light source 22a, a focusing lens 22b, an aperture diaphragm 22c, a pinhole plate 22d, a dichroic mirror 22e, and a collimator lens 22f (see Figure 3). The XY alignment indicator projection optical system 22 shares a half mirror 21e with the anterior segment observation optical system 21.

[0041] The XY alignment light source 22a emits infrared light. The collimator lens 22f is positioned on the optical path of the XY alignment index projection optical system 22 so that its focal point coincides with the pinhole plate 22d. In this XY alignment index projection optical system 22, the infrared light emitted from the XY alignment light source 22a is focused by the condensing lens 22b, passes through the aperture diaphragm 22c, and is guided to the hole in the pinhole plate 22d.

[0042] Infrared light passing through the hole in the pinhole plate 22d is reflected by the dichroic mirror 22e and guided to the collimator lens 22f, where it is further made into parallel light before being emitted from the collimator lens 22f to the half mirror 21e. This parallel infrared light is reflected by the half mirror 21e and then travels along the optical axis O1 of the anterior segment observation optical system 21. As a result, the parallel infrared light passes through the half mirror 21g and the chamber window glass 21d, and then passes inside the nozzle 21b, entering the eye under examination E as XY alignment indicator light.

[0043] The XY alignment indicator light incident on the eye E is reflected off the surface of the cornea Ec (not shown in the illustration) to form an XY spot. The aperture diaphragm 22c is positioned conjugate to the corneal apex Ep of the cornea Ec with respect to the collimator lens 22f.

[0044] The fixation target projection optical system 23 projects the fixation target onto the eye E under examination. This fixation target projection optical system 23 includes a fixation target light source 23a and a pinhole plate 23b (see Figure 3). Furthermore, the fixation target projection optical system 23 shares a dichroic mirror 22e and a collimator lens 22f with the XY alignment index projection optical system 22, and shares a half mirror 21e with the anterior segment observation optical system 21.

[0045] The fixation target light source 23a emits visible light as the fixation target light. This fixation target light is guided to the hole in the pinhole plate 23b, passes through the hole in the pinhole plate 23b and the dichroic mirror 22e, and is then emitted to the collimator lens 22f. The fixation target light is then made into approximately parallel light by the collimator lens 22f and emitted towards the half mirror 21e, where it is reflected and travels along the optical axis O1 of the anterior segment observation optical system 21. As a result, the fixation target light passes through the half mirror 21g and the chamber window glass 21d, then passes inside the nozzle 21b and reaches the eye E under examination. By having the subject fixate on this fixation target, the subject's line of sight can be fixed.

[0046] The applanation detection optical system 24 (see Figure 3) receives XY index reflected light and outputs a detection signal (also called an applanation signal or corneal deformation signal) indicating the amount of light from this 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 also shares a half mirror 21g with the anterior segment observation optical system 21.

[0047] When the surface of the cornea Ec is considered to be flat, lens 24a focuses the XY index reflected light onto the aperture of the pinhole plate 24b. The aperture of the pinhole plate 24b is located at the focal point of lens 24a.

[0048] The light receiving sensor 24c is a photodiode that outputs a detection signal corresponding to the amount of light reflected from the XY index received, for example. This light receiving sensor 24c outputs the detection signal (also called a flattened waveform signal) to the control device 16.

[0049] The XY index reflected light passes through the inside of the nozzle 21b, through the chamber window glass 21d, and reaches the half mirror 21g. Then, a portion of the XY index reflected light is reflected by the half mirror 21g and enters the pinhole plate 24b via the lens 24a.

[0050] When the surface of the cornea Ec becomes flat (flattened) due to the blowing of air from the nozzle 21b, the flattening detection optical system 24 allows the entire XY index reflected light that has reached the flattening detection optical system 24 to reach the light receiving sensor 24c through the pinhole plate 24b. In addition, when the cornea Ec is not in a flattened state, the flattening 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 flattening detection optical system 24 gradually increases as the surface of the cornea Ec changes from a convex state to a flattened state, and then gradually decreases as it changes from a flattened state to a concave state.

[0051] The Z-alignment index projection optical system 25 (see Figure 2) projects Z-alignment index light for Z-axis alignment onto the cornea Ec from an oblique direction. This Z-alignment index projection optical system 25 comprises a Z-alignment light source 25a, a focusing lens 25b, an aperture diaphragm 25c, a pinhole plate 25d, and a collimator lens 25e, all along the optical axis O2.

[0052] The Z-alignment light source 25a emits infrared light (e.g., wavelength 860 nm). The aperture diaphragm 25c is positioned conjugate to the corneal apex Ep with respect to the collimator lens 25e. The collimator lens 25e is positioned to focus on the hole in the pinhole plate 25d.

[0053] Infrared light emitted from the Z-alignment light source 25a is focused by the focusing lens 25b, passes through the aperture diaphragm 25c, and proceeds to the pinhole plate 25d. After passing through the hole in the pinhole plate 25d, the infrared light is made into parallel light by the collimator lens 25e, and then enters the eye E as a Z-alignment indicator light, where it is reflected by the cornea Ec, forming a bright spot image in the eye E.

[0054] The Z-alignment detection optical system 26 receives the reflected light from the cornea Ec of the Z-alignment index light (hereinafter referred to as Z-index reflected light) and detects the Z-axis positional relationship between the non-contact tonometer 14B and the cornea Ec. This 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.

[0055] The cylindrical lens 26b is one that has power in the Y-axis direction. The light receiving sensor 26c is a sensor capable of detecting the light receiving position of the Z-index reflected light on its light receiving surface, and for example, a line sensor or a PSD (Position Sensitive Detector) is used.

[0056] The Z-index reflected light is focused by the imaging lens 26a and then proceeds to the cylindrical lens 26b, where it is focused in the Y-axis direction, forming a bright spot image on the light receiving sensor 26c.

[0057] In the XZ plane, the light-receiving sensor 26c is in a positional relationship with respect to the imaging lens 26a that is conjugate to the bright spot image formed on the eye E by the Z-alignment index projection optical system 25. In the YZ plane, the light-receiving sensor 26c is in a positional relationship with respect to the imaging lens 26a and the cylindrical lens 26b that is conjugate to the corneal apex Ep. That is, since the light-receiving sensor 26c is conjugate to the aperture diaphragm 25c, even if the cornea Ec is shifted in the Y direction, the Z-index reflected light from the surface of the corneal Ec is efficiently incident on the light-receiving sensor 26c. The light-receiving sensor 26c then outputs a detection signal (hereinafter referred to as the Z detection signal) of the Z-index reflected light focused by the cylindrical lens 26b to the control device 16. This Z-detection signal indicates the relative position of the eye E in the Z-direction with respect to the non-contact tonometer 14B, more specifically, the distance in the Z-direction between the non-contact tonometer 14B and the eye E (corneal apex Ep). This enables Z-alignment detection. For this reason, the Z-alignment index projection optical system 25 and the Z-alignment detection optical system 26 also constitute part of the alignment detection unit of the present invention.

[0058] Furthermore, the signal intensity of this Z detection signal increases as the distance between the non-contact tonometer 14B and the eye E being examined approaches the appropriate working distance, and conversely decreases as it deviates from the appropriate working distance.

[0059] The spraying mechanism 34 (see Figure 3) includes a chamber 34a, a cylinder 34d, a connecting pipe 34e, a piston 34f, and a solenoid 34g.

[0060] A nozzle 21b is attached to the chamber 34a via a transparent glass plate 34b. A chamber window glass 21d is also provided inside the chamber 34a, facing the nozzle 21b. Furthermore, a pressure sensor 34c is provided inside the chamber 34a. This pressure sensor 34c outputs a pressure detection signal indicating the internal pressure inside the chamber 34a to the control device 16.

[0061] The cylinder 34d is connected to the chamber 34a via a connecting pipe 34e. This allows the inside of the cylinder 34d and the inside of the chamber 34a to communicate through the connecting pipe 34e. A piston 34f is also movably mounted inside the cylinder 34d. These cylinder 34d and piston 34f constitute an air compression chamber.

[0062] The solenoid 34g is a known solenoid actuator that moves a piston 34f within the cylinder 34d. Under the control of the control device 16, the solenoid 34g moves the piston 34f to compress the air inside the cylinder 34d. As a result, air is blown from the nozzle 21b towards the cornea Ec of the eye E being examined, via the connecting pipe 34e and the chamber 34a.

[0063] Furthermore, the spraying mechanism 34 can obtain the air pressure when air is sprayed from the nozzle 21b onto the cornea Ec by detecting the internal pressure of the chamber 34a using the pressure sensor 34c.

[0064] <Capacitive Sensor> Figure 4 is a perspective view of the spraying mechanism 34 (nozzle 21b) of the non-contact tonometer 14B, as seen from the patient's side. Figure 5 is a front view enlargement of the electrode 36a of the capacitive sensor 36 in Figure 4. In the figure, the symbol AX indicates the central axis of the nozzle 21b parallel to the Z direction, and the symbol HL indicates a parallel line, which is a straight line parallel to the X direction.

[0065] As shown in Figures 4 and 5, the front side of the non-contact tonometer 14B facing the subject is provided with a convex glass holder 35 for holding the anterior segment window glass 21c and a capacitive sensor 36 corresponding to the non-contact sensor of the present invention.

[0066] The capacitive sensor 36 detects the approach of the nozzle 21b to the subject's face (including the subject's eye E) under the control of the control device 16, which will be described later. This capacitive sensor 36 is, for example, of a self-capacitive type and has an electrode 36a and a detection circuit 36b.

[0067] The electrode 36a is provided on the glass holder 35 and forms a pseudo-condenser with the subject's face. When viewed from the tip side of the nozzle 21b, the electrode 36a is formed in the region below the parallel line HL within the annular region surrounding the nozzle 21b, that is, it is formed in a substantially semi-annular shape. The phrase "formed in the region below the parallel line HL" here includes both cases where it is formed in the entire region below the parallel line HL, as shown in Figures 4 and 5, and cases where it is formed in a part of the region below the parallel line HL.

[0068] The detection circuit 36b is provided, for example, inside (or outside) the measuring head 14 and is connected to the electrode 36a via wiring 36c. This detection circuit 36b detects the capacitance generated by the pseudo-capacitor described above and outputs the detected value to the control device 16. The capacitance of the pseudo-capacitor increases as the distance between the electrode 36a and the subject's face decreases, and conversely, the capacitance of the pseudo-capacitor decreases as the distance between the electrode 36a and the subject's face increases. Therefore, the distance between the electrode 36a (nozzle 21b) and the subject's face can be detected based on the capacitance detected by the detection circuit 36b. As a result, the approach of the nozzle 21b to the subject's face can be detected by the capacitive sensor 36.

[0069] Figure 6 is an explanatory diagram illustrating the directivity of the capacitive sensor 36. The symbol RD in the figure indicates the detection range of the capacitive sensor 36. The detection range RD shown in Figure 6 is just one example, and its range can be changed as needed.

[0070] As shown in Figure 6, by forming the electrode 36a in a substantially semi-annular shape, the detection range RD of the capacitive sensor 36 is limited above the central axis AX when the nozzle 21b and glass holding portion 35 are viewed from any one side in the X direction. As a result, the capacitive sensor 36 has directionality towards the front of the nozzle 21b, but when the nozzle 21b is viewed from any one side in the X direction, the directionality above the central axis AX is weaker than that below it.

[0071] By weakening the directivity of the capacitive sensor 36 towards the upper side of the central axis AX in this way, even when the nozzle 21b is brought close to the eye E under examination, a sufficient distance is maintained between the electrode 36a and the subject's forehead. Therefore, even if the subject's forehead is prominent (i.e., the subject has deep facial features), the capacitive sensor 36 is prevented from falsely detecting the examiner's forehead. Furthermore, even when the examiner is performing an eyelid-opening procedure to open the subject's eyelids, a sufficient distance is maintained between the electrode 36a and the examiner's fingers, thus preventing the capacitive sensor 36 from falsely detecting the examiner's fingers.

[0072] In this embodiment, the electrode 36a is formed in a substantially semi-annular shape to weaken the directivity of the capacitive sensor 36 with respect to the upper side of the central axis AX. However, the position and shape of the electrode 36a can be changed as appropriate, as long as it is possible to detect the approach of the subject's face or the like to the nozzle 21b.

[0073] <Control device> Figure 7 is a functional block diagram of the control device 16. As shown in Figure 7, the control device 16 provides overall control over the operation of the ophthalmic device 10. The control device 16 includes an arithmetic circuit composed of various processors and memory. The various processors include CPUs (Central Processing Units), GPUs (Graphics Processing Units), ASICs (Application Specific Integrated Circuits), and programmable logic devices [e.g., SPLDs (Simple Programmable Logic Devices), CPLDs (Complex Programmable Logic Devices), and FPGAs (Field Programmable Gate Arrays)]. The various functions of the control device 16 may be implemented by a single processor, or by multiple processors of the same or different types.

[0074] The control device 16 is connected to the aforementioned drive mechanism 13, measuring head 14 (auto refractometer 14A, non-contact tonometer 14B), and monitor 15, etc. This control device 16 provides overall control of the operation of the ophthalmic device 10, such as alignment detection, alignment, refractometer measurement, intraocular pressure measurement, and operation confirmation of the capacitive sensor 36.

[0075] The control device 16 functions as a first alignment control unit 40, a first measurement control unit 41, a second alignment control unit 42, a hazard avoidance operation control unit 43, a second measurement control unit 44, an operation confirmation control unit 45, and a notification control unit 46 by reading and executing a control program (not shown). Note that the "~unit" described in relation to the control device 16 may also be a "~circuit," a "~device," or a "~equipment." In other words, the "~unit" described may consist of firmware, software, hardware, or a combination thereof.

[0076] The first alignment control unit 40 controls the auto-alignment of the auto-refractometer 14A in the XYZ direction relative to the eye E before the start of refractometer measurement of the eye E under examination. The first alignment control unit 40 first controls the various optical systems of the auto-refractometer 14A and performs XYZ alignment detection to detect the relative position of the eye E under examination in the XYZ direction relative to the auto-refractometer 14A using a known method (see, for example, Patent Document 1 above).

[0077] Next, the first alignment control unit 40 automatically drives the drive mechanism 13 based on the detection result of the XYZ alignment detection to perform automatic alignment of the autorefractometer 14A in the XYZ direction for the eye E under examination.

[0078] The first measurement control unit 41 performs refractometer measurement of the eye E under examination using the autorefractometer 14A after the auto-alignment of the autorefractometer 14A is completed. Since refractometer measurement using the autorefractometer 14A is also a known technique (see, for example, Patent Document 1 above), a detailed explanation is omitted here.

[0079] The second alignment control unit 42 controls the automatic alignment (coarse alignment, precise alignment) of the non-contact tonometer 14B in the XYZ directions for the eye E after refractory keratometry measurement and before intraocular pressure measurement begins. This second alignment control unit 42 functions as a coarse alignment unit 42a, a detection control unit 42b, and an alignment execution unit 42c.

[0080] The coarse alignment unit 42a automatically drives the drive mechanism 13 after refractometer measurement to perform coarse alignment, including downward and forward movement of the measurement head 14 as described above. For example, when performing coarse alignment automatically, the measurement head 14 is moved downward so that the pupil center of the eye E specified by the examiner on the monitor 15 screen moves to the center position of the screen (image sensor 21i), and the measurement head 14 is moved forward until the light receiving sensor 26c outputs a Z detection signal. This allows the non-contact tonometer 14B (measurement head 14) to be moved to a position where XYZ alignment detection is possible.

[0081] The detection control unit 42b functions as the alignment detection unit of the present invention together with the anterior segment observation optical system 21, the XY alignment index projection optical system 22, the Z alignment index projection optical system 25, and the Z alignment detection optical system 26. The detection control unit 42b controls the anterior segment observation optical system 21 and the XY alignment index projection optical system 22 described above to perform XY alignment detection to detect the relative position of the eye E in the XY direction with respect to the non-contact tonometer 14B. The detection control unit 42b also controls the Z alignment index projection optical system 25 and the Z alignment detection optical system 26 to perform Z alignment detection to detect the relative position of the eye E in the Z direction (Z-direction distance DZ, see Figure 8) with respect to the non-contact tonometer 14B.

[0082] Based on the detection result of the XYZ alignment detection by the detection control unit 42b, the alignment execution unit 42c drives the drive mechanism 13 to perform precise XYZ alignment of the non-contact tonometer 14B with respect to the eye E under examination.

[0083] The hazard avoidance action control unit 43 operates the capacitive sensor 36 while the second alignment control unit 42 is performing auto-alignment in the XYZ directions (especially during the forward movement of the head during rough alignment) and repeatedly acquires capacitance detection values ​​from the capacitive sensor 36. When the detection value acquired from the capacitive sensor 36 exceeds a predetermined threshold, that is, when the nozzle 21b approaches the subject's face, the hazard avoidance action control unit 43 controls the drive mechanism 13 to perform a predetermined hazard avoidance action. This hazard avoidance action is not particularly limited as long as it stops the movement of the measurement head 14 (non-contact tonometer 14B) especially in the forward direction in the Z direction, and examples include stopping the drive mechanism 13 or moving the measurement head 14 backward in the Z direction.

[0084] The second measurement control unit 44 activates the blowing mechanism 34 after the auto-alignment by the second alignment control unit 42 is completed, causing the blowing mechanism 34 to blow air onto the cornea Ec. While air is being blown onto the cornea Ec from the nozzle 21b, the second measurement control unit 44 continuously performs the projection of XY alignment index light onto the cornea Ec by the XY alignment index projection optical system 22, and the imaging of XY index reflected light and output of the detection signal by the applanation detection optical system 24. Then, the second measurement control unit 44 calculates the intraocular pressure value of the eye E under examination using a known method based on the detection signal continuously output from the applanation detection optical system 24 and the detection result of the pressure sensor 34c.

[0085] The operation confirmation control unit 45 controls the operation confirmation of the capacitive sensor 36, that is, the determination of whether or not the capacitive sensor 36 is operating normally. This operation confirmation of the capacitive sensor 36 is performed at any time, for example, immediately after the power of the ophthalmic device 10 is turned on, after refractometer measurement (before intraocular pressure measurement), after intraocular pressure measurement, after a predetermined period of time has elapsed (after a predetermined number of intraocular pressure measurements have been performed), or each time the subject changes (after the previous measurement results have been reset). In this embodiment, the operation confirmation of the capacitive sensor 36 is described as being performed immediately after the power is turned on.

[0086] Figure 8 is an explanatory diagram illustrating a specific method for verifying the operation of the capacitive sensor 36 of the first embodiment. In Figure 8, the Z-alignment detection range RZ1 corresponds to the first detection range of the present invention and shows an example of the range in which the Z-alignment of the eye under examination E can be detected by the Z-alignment index projection optical system 25 and the Z-alignment detection optical system 26. The Z-direction detection range RZ2 corresponds to the second detection range of the present invention and shows an example of the detectable range in the Z direction within the detection range RD (see Figure 6) of the capacitive sensor 36.

[0087] As shown in Figure 8, the Z-direction detection range RZ2 is wider than the Z-alignment detection range RZ1 and encompasses the Z-alignment detection range RZ1. Therefore, if Z-alignment detection is possible, the cornea Ec of the eye under examination is reliably included within the range of the Z-direction detection range RZ2 of the capacitive sensor 36. If the capacitive sensor 36 is functioning correctly in this state, the detected capacitance value output from the capacitive sensor 36 will be above a certain amount. Based on this, the operation confirmation control unit 45 confirms the operation of the capacitive sensor 36 based on the detected value of the capacitive sensor 36 in the state where Z-alignment detection is possible.

[0088] Returning to Figure 7, the operation confirmation control unit 45 functions as a confirmation unit 45a, a position adjustment unit 45b, and a determination unit 45c when confirming the operation of the capacitive sensor 36.

[0089] The confirmation unit 45a activates the Z-alignment index projection optical system 25 and the Z-alignment detection optical system 26 when confirming the operation of the capacitive sensor 36. The confirmation unit 45a then checks whether Z-alignment detection is possible, that is, whether the Z-direction distance DZ, which is the distance in the Z direction between the non-contact tonometer 14B and the cornea Ec (corneal apex Ep), can be detected. Specifically, the confirmation unit 45a checks whether the Z-direction distance DZ can be detected based on whether or not a Z detection signal is output from the light receiving sensor 26c of the Z-alignment detection optical system 26. In this case, the cornea Ec corresponds to the target object of the present invention.

[0090] If the confirmation unit 45a does not confirm that the Z-direction distance DZ is detectable, the position adjustment unit 45b adjusts the position of the cornea Ec within the Z-alignment detection range RZ1 by, for example, automatically driving the drive mechanism 13 as in the rough alignment described above, or by driving the drive mechanism 13 in response to manual movement operations. This switches the state from one in which the Z-direction distance DZ (Z-alignment detection) is undetectable to one in which it is detectable.

[0091] When the confirmation unit 45a confirms that the distance DZ in the Z direction is detectable, the determination unit 45c obtains the capacitance detection value from the capacitive sensor 36 and determines whether the capacitive sensor 36 is operating normally based on whether this detection value is equal to or greater than a predetermined determination threshold. This determination threshold is determined in advance by conducting experiments or simulations based on, for example, the type of capacitive sensor 36, the distance DZ in the Z direction, and the temperature and humidity of the installation environment of the ophthalmic device 10. This allows for verification of the operation of the capacitive sensor 36.

[0092] Figure 9 is an explanatory diagram showing an example of the notification of warning information 50 and 52 by the notification control unit 46. As shown in Figure 9 and Figure 7 described above, the notification control unit 46, together with the monitor 15, constitutes the notification unit of the present invention. When the determination unit 45c determines that the capacitive sensor 36 is not operating normally, the notification control unit 46 displays warning information 50 to that effect on the monitor 15 (see reference numeral 9A in Figure 9).

[0093] Furthermore, the notification control unit 46 displays warning information 52 on the monitor 15 indicating that the nozzle 21b is close to the subject's face when the capacitance detection value obtained by the aforementioned danger avoidance operation control unit 43 from the capacitive sensor 36 exceeds a threshold (see reference numeral 9B in Figure 9).

[0094] Alternatively, the notification control unit 46 may, instead of displaying the warning information 50 and 52 on the monitor 15, or in addition to displaying it, output the warning information 50 and 52 as sound from a speaker (not shown), or vibrate a part of the ophthalmic device 10.

[0095] [Operation of the First Embodiment] Figure 10 is a flowchart showing the flow of refractometer measurement and intraocular pressure measurement of the eye E being examined using the ophthalmic device 10 of the first embodiment. Figure 11 is a flowchart showing the flow of the operation confirmation process of the capacitive sensor 36 according to the non-contact sensor operation confirmation method of the present invention.

[0096] As shown in Figure 10, when the power to the ophthalmic device 10 is turned ON (step S1), the operation confirmation control unit 45 of the control device 16 is activated and the operation confirmation process of the capacitive sensor 36 is started (step S2).

[0097] As shown in Figure 11, in the operation verification step (step S2) of the capacitive sensor 36, the verification unit 45a activates the Z-alignment index projection optical system 25 and the Z-alignment detection optical system 26, causing the Z-alignment index light to be emitted from the Z-alignment index projection optical system 25 (step S2A). In the initial state when the power is turned on, the cornea Ec is not within the Z-alignment detection range RZ1, so the Z-alignment index light is not irradiated onto the cornea Ec. As a result, the Z-alignment detection optical system 26 cannot detect the reflected Z-index light, and no Z-detection signal is output from the Z-alignment detection optical system 26.

[0098] Next, the position adjustment unit 45b automatically drives the drive mechanism 13 or drives it in response to manual movement operation to adjust the position of the measuring head 14 in the Z direction, thereby positioning the cornea Ec within the Z alignment detection range RZ1 (NO in steps S2B and S2C).

[0099] When the corneal Ec is positioned within the Z-alignment detection range RZ1, the Z-alignment index light is shone onto the corneal Ec, causing the Z-alignment detection optical system 26 to detect the reflected Z-index light and output a Z-detection signal (YES in step S2C). As a result, the verification unit 45a confirms that the Z-direction distance DZ can be detected (step S2D, corresponding to the verification step of the present invention).

[0100] Next, the determination unit 45c obtains a capacitance detection value from the capacitive sensor 36 (step S2E), and determines whether the capacitive sensor 36 is operating normally based on whether this detection value is equal to or greater than a determination threshold (step S2F, corresponding to the determination step of the present invention).

[0101] If the determination unit 45c determines that the capacitive sensor 36 is not functioning correctly (NO in step S2G), the notification control unit 46 displays warning information 50 on the monitor 15 as shown by reference numeral 9A in Figure 9 (step S2H). This notifies the examiner that the capacitive sensor 36 is not functioning correctly and prompts them to take appropriate action (check, replace, repair, etc., the capacitive sensor 36).

[0102] On the other hand, if the determination unit 45c determines that the capacitive sensor 36 is operating normally (YES in step S2G), the operation verification process for the capacitive sensor 36 is completed and the process moves to the next step (step S2I).

[0103] Returning to Figure 10, once the operation verification process of the capacitive sensor 36 (step S2) is completed, the first alignment control unit 40 controls the various optical systems of the autorefractometer 14A to perform XYZ alignment detection. Next, based on the detection result of the XYZ alignment detection, the first alignment control unit 40 drives the drive mechanism 13 to perform auto-alignment of the autorefractometer 14A in the XYZ direction relative to the eye E under examination (step S3).

[0104] Once this auto-alignment is complete, the first measurement control unit 41 causes the auto-refractometer 14A to perform refractometer measurement of the eye E under examination (step S4).

[0105] Once the refractometer measurement of the eye E is complete, the second alignment control unit 42 drives the drive mechanism 13 to start the auto-alignment of the non-contact tonometer 14B to the eye E (step S5).

[0106] First, the coarse alignment unit 42a drives the drive mechanism 13 to perform coarse alignment of the measurement head 14 (head downward movement, head forward movement) to move the non-contact tonometer 14B to a position where alignment detection is possible. Next, the detection control unit 42b controls the anterior segment observation optical system 21 and the XY alignment index projection optical system 22 to perform XY alignment detection, and also controls the Z alignment index projection optical system 25 and the Z alignment detection optical system 26 described above to perform Z alignment detection. Then, the alignment execution unit 42c drives the drive mechanism 13 based on the detection results of the XYZ alignment detection to perform precise XYZ alignment of the non-contact tonometer 14B with respect to the eye E under examination.

[0107] While the auto-alignment (coarse alignment, precise alignment) of the non-contact tonometer 14B is being performed, the hazard avoidance action control unit 43 activates the capacitive sensor 36 and repeatedly acquires capacitance detection values ​​from the capacitive sensor 36 (NO in step S6, NO in step S7). If the detection value acquired from the capacitive sensor 36 exceeds a threshold (YES in step S6), the hazard avoidance action control unit 43 controls the drive mechanism 13 to perform a hazard avoidance action (stop, retreat) (step S8). Since the approach of the nozzle 21b etc. to the subject's face (including the subject's eye E) is detected using the operationally confirmed capacitive sensor 36, contact between the nozzle 21b etc. and the subject's face is reliably prevented.

[0108] Next, the notification control unit 46 displays warning information 52 on the monitor 15 as shown by reference numeral 9B in Figure 9 (step S9). This allows the system to notify the user that the nozzle 21b or the like is approaching the subject's face.

[0109] If the detection value output from the capacitive sensor 36 does not exceed the threshold and the auto-alignment of the non-contact tonometer 14B is completed (NO in step S6, YES in step S7), the second measurement control unit 44 controls the spraying mechanism 34, the XY alignment index projection optical system 22, and the applanation detection optical system 24 to perform intraocular pressure measurement of the eye E under examination (step S10).

[0110] As described above, in the first embodiment, the operation of the capacitive sensor 36 is verified using the existing Z-alignment index projection optical system 25 and Z-alignment detection optical system 26, eliminating the need to separately provide components for this operation verification in the ophthalmic device 10. As a result, the operation verification of the capacitive sensor 36 can be performed at low cost without requiring new installation space.

[0111] [Second Embodiment] Figure 12 is an explanatory diagram illustrating the method for verifying the operation of the capacitive sensor 36 using the ophthalmic device 10 of the second embodiment. In the ophthalmic device 10 of the first embodiment described above, the verification unit 45a checks whether the distance DZ in the Z direction between the non-contact tonometer 14B and the eye under examination E (corneal apex Ep) can be detected, so the eye under examination E (human eye) is required to verify the operation of the capacitive sensor 36. In contrast, in the ophthalmic device 10 of the second embodiment, a model eye unit 100 is used instead of the eye under examination E to verify the operation of the capacitive sensor 36.

[0112] The ophthalmic apparatus 10 of the second embodiment has basically the same configuration as the ophthalmic apparatus 10 of the first embodiment, except that the model eye unit 100 is supported by the jaw rest 12a. For this reason, components that are functionally or structurally identical to those of the first embodiment are denoted by the same reference numerals and their descriptions are omitted.

[0113] The model eye unit 100 consists of a model eye 102, a conductive material 104, and a model eye support base 106.

[0114] The model eye 102 is modeled after a human eye and is made of, for example, a glass sphere. This model eye 102 comprises a roughly hemispherical corneal portion 102a corresponding to the cornea Ec, and a cylindrical connecting portion 102b for connecting the corneal portion 102a to the model eye support base 106. In the figure, reference numeral 102p indicates the apex of the corneal portion 102a, which corresponds to the corneal apex Ep.

[0115] The conductive material 104 has a fitting hole (not shown) into which the connecting portion 102b fits, and is externally fitted and fixed to the connecting portion 102b. The conductive material 104 is also connected to earth. The conductive material 104 connected to earth can be easily detected by the capacitive sensor 36. Therefore, if the conductive material 104 is located within the Z-direction detection range RZ2 of the normal capacitive sensor 36, the detected capacitance value output from the capacitive sensor 36 will be above a certain amount. The Z-direction position of the conductive material 104 is adjusted so that it is located within the Z-direction detection range RZ2 when the corneal portion 102a is located within the Z-alignment detection range RZ1. The conductive material 104 may be omitted if the model eye 102 can be detected by the capacitive sensor 36.

[0116] The model eye support base 106 is placed on the jaw rest 12a while holding the model eye 102 and the conductive material 104. As a result, the model eye 102 is supported on the jaw rest 12a via the model eye support base 106. Consequently, the corneal portion 102a can be positioned in the Z-alignment detection range RZ1, and the conductive material 104 can be positioned in the Z-direction detection range RZ2.

[0117] In the second embodiment, when the operation of the capacitive sensor 36 is being checked, if the corneal portion 102a is positioned within the Z-alignment detection range RZ1, the Z-alignment index projection optical system 25 projects Z-alignment index light onto the corneal portion 102a. The Z-alignment detection optical system 26 then detects the Z-index reflected light reflected by the corneal portion 102a and outputs a Z-detection signal. As a result, the confirmation unit 45a of the second embodiment can confirm whether the Z-direction distance DZ between the non-contact tonometer 14B and the corneal portion 102a (vertex 102p) can be detected, based on whether or not a Z-detection signal is output from the Z-alignment detection optical system 26, similar to the first embodiment. In this case, the corneal portion 102a corresponds to the target object of the present invention.

[0118] In the second embodiment, the determination unit 45c obtains a capacitance value corresponding to the conductive material 104 from the capacitive sensor 36 when the confirmation unit 45a confirms that the distance DZ in the Z direction is detectable, and determines whether the capacitive sensor 36 is operating normally based on whether this detection value is equal to or greater than a determination threshold. The determination threshold in the second embodiment is determined in advance by conducting experiments or simulations based on, for example, the type of capacitive sensor 36, the distance DZ in the Z direction, the material of the conductive material 104, and the temperature and humidity of the installation environment of the ophthalmic device 10.

[0119] As described above, in the ophthalmic device 10 of the second embodiment, the operation of the capacitive sensor 36 can be confirmed using a model eye 102 instead of the eye E under examination. Therefore, in the second embodiment, unlike the first embodiment, it is not necessary to adjust the position of the cornea Ec within the Z-alignment detection range RZ1 in order to confirm the operation of the capacitive sensor 36, that is, it is not necessary to bring the nozzle 21b of the non-contact tonometer 14B close to the patient's face. As a result, there is no risk of the nozzle 21b coming into contact with the patient's face when confirming the operation of the capacitive sensor 36. Furthermore, the same effects as in the first embodiment can be obtained.

[0120] [others] In the embodiments described above, auto-alignment was used as an example for aligning the measurement head 14 (autorefractometer 14A, non-contact tonometer 14B) to the eye E being examined. However, the present invention can also be applied to manual alignment. In manual alignment, the alignment status of the measurement head 14 to the eye E being examined is displayed on the monitor 15 based on the detection result of XYZ alignment detection. The examiner then operates the operation screen on the monitor 15 according to this display to adjust the position of the measurement head 14 in the XYZ directions.

[0121] In each of the above embodiments, the position adjustment unit 45b drives the drive mechanism 13 to adjust the position of the cornea Ec or corneal portion 102a within the Z alignment detection range RZ1. However, the position of the subject's face (subject eye E) or the model eye 102 may also be adjusted by raising or lowering the chin rest 12a, etc., in the Y direction in response to the raising and lowering operation of the face support unit 12. In other words, the position adjustment unit 45b only needs to move at least one of the measurement head 14 and the target object (cornea Ec, corneal portion 102a).

[0122] In each of the above embodiments, a capacitive sensor 36 is used to detect the approach of the nozzle 21b to the subject's face. However, various known non-contact sensors (proximity sensors), such as ultrasonic sensors and infrared proximity sensors, may also be used. In this case, the operation and calibration of the non-contact sensor are performed using a specific structure (shape and material are not particularly limited) of the ophthalmic device 10 that can be detected by the non-contact sensor.

[0123] In each of the above embodiments, it is confirmed whether or not the Z-direction distance DZ (Z-alignment detection) can be detected using the Z-alignment index projection optical system 25 and the Z-alignment detection optical system 26. However, there are no particular limitations as long as it is an existing alignment detection optical system (including a stereo camera) that can detect the Z-direction distance DZ (Z-alignment detection).

[0124] In the embodiments described above, a combined device comprising an autorefractometer 14A and a non-contact tonometer 14B was used as an example for the ophthalmic device 10, but the present invention can also be applied to a standalone non-contact tonometer 14B. Furthermore, the present invention can also be applied to ophthalmic devices and combined devices thereof that acquire various ocular characteristics of the eye E under examination (refractive power, corneal curvature, intraocular pressure, corneal endothelial cell count, fundus image, tomographic image, etc.). [Explanation of Symbols]

[0125] 10...Ophthalmological equipment 11…Bass 12…Face support section 12a... Jaw support 12b... Forehead area 13…Drive mechanism 14… Measuring head 14A... Autorefractor / keratometer 14B...Non-contact tonometer 15…Monitor 16...Control device 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 Indicative Projection Optical System 22a...Light source for XY alignment 22b... Focusing 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…Approach detection optical system 24a... Lens 24b... Pinhole plate 24c... Light receiving sensor 25…Z-alignment index projection optics 25a...Light source for Z alignment 25b... Focusing lens 25c…Aperture diaphragm 25d... Pinhole plate 25e...Collimator lens 26…Z-alignment detection optical system 26a…Imaging lens 26b... Cylindrical lens 26c... Light receiving sensor 34…Spraying mechanism 34a... Chamber 34b... Glass plate 34c... Pressure sensor 34d...Cylinder 34e…Communication pipe 34f... Piston 34g... solenoid 35...Glass holding part 36…Capacitive Sensor 36a...Electrode 36b...Detection circuit 36c...Wiring 40…First Alignment Control Unit 41...First Measurement Control Unit 42...Second Alignment Control Unit 42a...Rough alignment section 42b...Detection and Control Unit 42c... Alignment Execution Unit 43... Danger Avoidance Action Control Unit 44...Second Measurement Control Unit 45... Operation Confirmation Control Unit 45a...Verification section 45b…Position adjustment section 45c...judgment section 46…Notification Control Unit 50…Warning Information 52…Warning Information 100...Model Eye Unit 102...Model eye 102a...Cornea part 102b...Connection part 102p...Peak 104...Conductive material 106…Model eye support stand AX…Central axis DZ…Z direction distance E...Eye being examined Ec…cornea Ep...corneal apex HL…Parallel line O1...Optical axis O2…optical axis O3... Optical axis RD...Detection range RZ1... Z-alignment detection range RZ2...Z direction detection range

Claims

1. an eye characteristic acquisition unit that acquires eye characteristics of the subject's eye; a drive mechanism that moves the eye characteristic acquisition unit relative to the eye to be examined, and that is capable of moving at least the eye characteristic acquisition unit in a front-to-rear direction toward the eye to be examined and a rearward direction away from the eye to be examined; an alignment detection unit that detects a relative position of the subject's eye with respect to the eye characteristic acquisition unit and has a function of detecting at least a distance in the front-to-back direction between the eye characteristic acquisition unit and the subject's eye; an alignment execution unit that automatically drives the drive mechanism or drives the drive mechanism in response to a manual movement operation based on a detection result of the alignment detection unit, thereby aligning the eye characteristic acquisition unit with the subject's eye; a non-contact sensor provided in the eye characteristic acquisition unit, capable of detecting the approach of the eye characteristic acquisition unit to the face of the subject in a non-contact manner, the non-contact sensor having a second detection range that includes the first detection range of the alignment detection unit in the front-rear direction; a confirmation unit that confirms whether the alignment detection unit is able to detect the distance in the front-rear direction between the eye characteristic acquisition unit and a target object within the first detection range; a determination unit that, when the confirmation unit has confirmed that the alignment detection unit is capable of detecting the distance in the front-rear direction, determines whether the non-contact sensor operates normally based on the detection value of the non-contact sensor; and An ophthalmic device comprising:

2. The ophthalmologic apparatus according to claim 1 , wherein the determination unit determines whether the non-contact sensor is operating normally based on whether the detection value of the non-contact sensor is equal to or greater than a determination threshold.

3. The ophthalmic device of claim 1 or 2, further comprising a position adjustment unit that moves at least one of the eye characteristic acquisition unit and the target object to adjust the position of the target object within the first detection range when the confirmation unit does not confirm that the alignment detection unit can detect the distance in the forward / backward direction.

4. The ophthalmologic apparatus according to claim 1 , wherein the confirmation unit confirms whether or not the distance in the front-rear direction between the subject's eye and the target object can be detected.

5. The ophthalmologic apparatus according to claim 1 , wherein the confirmation unit confirms whether or not the distance in the front-to-rear direction between a model eye that imitates the subject's eye and the target object can be detected.

6. a face support portion that supports the face of the subject and includes a chin rest portion that receives the subject's chin and a forehead rest portion against which the subject's forehead abuts; The ophthalmologic apparatus according to claim 5 , wherein the chin rest supports the model eye and a conductive material connected to ground.

7. The ophthalmic device according to any one of claims 1 to 6, further comprising an alarm unit that issues a warning when the determination unit determines that the non-contact sensor is not operating normally or when the detection value of the non-contact sensor exceeds a threshold value during the alignment.

8. The ophthalmic device according to any one of claims 1 to 7, further comprising a danger avoidance operation control unit that controls the drive mechanism to perform a danger avoidance operation when the detection value of the non-contact sensor exceeds a threshold value during the alignment.

9. an eye characteristic acquisition unit that acquires eye characteristics of the subject's eye; a drive mechanism that moves the eye characteristic acquisition unit relative to the eye to be examined, and that is capable of moving at least the eye characteristic acquisition unit in a front-to-rear direction toward the eye to be examined and a rearward direction away from the eye to be examined; an alignment detection unit that detects a relative position of the subject's eye with respect to the eye characteristic acquisition unit and has a function of detecting at least a distance in the front-to-back direction between the eye characteristic acquisition unit and the subject's eye; an alignment execution unit that automatically drives the drive mechanism or drives the drive mechanism in response to a manual movement operation based on a detection result of the alignment detection unit, thereby aligning the eye characteristic acquisition unit with the subject's eye; a non-contact sensor provided in the eye characteristic acquisition unit, capable of detecting the approach of the eye characteristic acquisition unit to the face of the subject in a non-contact manner, the non-contact sensor having a second detection range that includes the first detection range of the alignment detection unit in the front-rear direction; A method for checking the operation of a non-contact sensor in an ophthalmic apparatus, comprising: a confirmation step of confirming whether the alignment detection unit can detect the distance in the front-to-rear direction between the eye characteristic acquisition unit and a target object within the first detection range; a determining step of determining whether the non-contact sensor operates normally based on a detection value of the non-contact sensor when it is determined in the confirming step that the alignment detection unit can detect the distance in the front-rear direction; A method for checking the operation of a non-contact sensor.

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