JP2022002768A - Ophthalmologic apparatus - Google Patents

Abstract

To provide an ophthalmologic apparatus that can accurately grasp the astigmatic state of a subject.SOLUTION: A main controller 16 that controls the display contents of a display 22a is provided on the optical axis of an optotype projection system 22 that displays the optotype to an eye to be inspected. A first optotype S1 for acquiring the angle of the astigmatic axis of the eye to be inspected that is a first radial chart 30 composed of a plurality of radial lines extending from a center position O of an optometric display area A in a direction of dividing all directions in the radial direction into a plurality of directions for predetermined angles and a second optotype S2 that is generated with an angle value acquired using the first optotype S1 as a reference, divides a predetermined angle range in the radial direction in detail that the angle of the astigmatic axis acquired using the first radial chart 30 is centered and is a second radial chart 40 composed of a plurality of radial lines symmetrical across the radiation center position are switched to display, on a display 22a arranged inside a measurement head housing 20a in which a measurement optical system OS is built.SELECTED DRAWING: Figure 4

Description

The present invention relates to an ophthalmic apparatus.

Conventionally, an optotype projection system that displays an optotype on the eye to be inspected and an observation system that observes the anterior segment of the eye to be inspected are built into the measurement head housing, and the optotype projection system has a display that can change the display content. There are known ophthalmic devices (see, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2017-63978

By the way, in the conventional ophthalmic apparatus, in the optotype projection system, it is possible to display a subjective test optotype for subjectively measuring the ocular characteristics of the eye to be inspected. Therefore, in order to detect the angle of the astigmatic axis of the eye to be inspected, it is conceivable to display a graphic target such as a radial chart composed of a large number of radial lines on the display.

Here, the subjective examination of the astigmatic axis angle of the eye to be inspected is generally performed by making the subject visually recognize a graphic target such as a radial chart and having the subject respond to the appearance. .. However, it has been difficult to accurately grasp the astigmatic state only by the inspection using one kind of graphic target.

The present invention has been made focusing on the above problems, and an object of the present invention is to provide an ophthalmic apparatus capable of accurately grasping the astigmatic state of a subject.

In order to achieve the above object, the ophthalmic apparatus of the present invention comprises a display provided on the optical axis of an optotype projection system for displaying an optotype on an eye to be inspected, and a display controller for controlling the display contents of the display. The display is arranged inside a measurement head housing incorporating a measurement optical system for acquiring information on the eye to be inspected, and the display controller acquires the angle of the astigmatic axis of the eye to be inspected on the display. The first optotype to be displayed and the second optotype generated based on the angle value acquired by using the first optotype are switched and displayed. The first optotype extends from the center position of the optotype display area displaying the first optotype and the second optotype in a direction in which all directions in the radial direction are divided into a plurality of portions at predetermined angles. The first radial chart is composed of the radial lines of the above, and the second target is a radial center obtained by finely dividing a predetermined angle range in the radial direction centered on the angle of the radiant axis acquired by using the first radial chart. It is characterized in that it is a second radial chart composed of a plurality of radial lines that are symmetrical with respect to the position.

In the ophthalmic apparatus configured in this way, the angle of the astigmatic axis is acquired by using the first optotype displayed on the display. Then, when the angle value of the astigmatism axis is acquired, the display is switched, and the astigmatism state of the eye to be inspected can be observed using the second optotype generated based on this angle value. That is, it is possible to switch the display on the display according to the progress of the examination and accurately grasp the astigmatic state of the eye to be inspected. In addition, it is possible to perform a subjective test in a stationary state without rotating the shape of the astigmatism axis test chart. That is, it is possible to perform an inspection in which the display state of the optotype is kept constant, and the optotype can be appropriately visually recognized over time.

It is a perspective view which shows the appearance of the ophthalmic apparatus of Example 1. FIG. It is a block diagram which shows the structure of the control system of the ophthalmic apparatus of Example 1. FIG. It is explanatory drawing for demonstrating the optical configuration of the ophthalmic apparatus of Example 1. FIG. It is explanatory drawing which shows the 1st optotype of Example 1. FIG. It is explanatory drawing which shows the 2nd optotype of Example 1. FIG. It is explanatory drawing which shows the 1st optotype of Example 2. FIG. It is explanatory drawing which shows the 2nd optotype of Example 2. FIG. It is explanatory drawing which shows the modification of the 2nd optotype of Example 2.

Hereinafter, embodiments for carrying out the ophthalmic apparatus of the present invention will be described with reference to Examples 1 and 2 shown in the drawings.

(Example 1)
First, based on FIGS. 1 to 5, the configuration of the ophthalmic apparatus 10 of Example 1 is described as "overall configuration", "detailed configuration of control system", "detailed configuration of measurement optical system", and "details of astigmatism axis test chart". The explanation will be divided into "configuration".

[overall structure]
The ophthalmic apparatus 10 shown in FIG. 1 is a binocular open type ophthalmic apparatus in which both eyes are simultaneously measured for characteristics of an eye to be inspected while the subject has both left and right eyes open.

As shown in FIG. 1, the ophthalmic apparatus 10 of the first embodiment includes a base 11 installed on a floor surface, an optometry table 12, a support column 13, an arm 14, and a measurement head 20. .. Further, although not shown in FIG. 1, the ophthalmic apparatus 10 includes a controller 19a for an examiner such as a tablet terminal, a controller 19b for an examinee such as a control lever unit, and a display device 19c such as a liquid crystal display. is doing. In the ophthalmic apparatus 10, the subject facing the optometry table 12 measures the characteristics of the optometry in a state where the forehead is in contact with the forehead portion 15 of the measurement head 20. In the following, the left-right direction is the X direction, the vertical direction (vertical direction) is the Y direction, and the X direction and the direction orthogonal to the Y direction (the front-back direction of the measurement head 20) are the Z directions when viewed from the subject. ..

The optometry table 12 is supported by the base 11 and its height position can be adjusted. The support column 13 stands upright in the Y direction from the rear end portion of the optometry table 12, and an arm 14 is provided on the upper portion. The arm 14 suspends and supports the measurement head 20 above the optometry table 12, and extends in the Z direction from the support column 13. The arm 14 is attached to the support column 13 so as to be vertically movable.

Below the eye examination table 12, a control box 17 is provided in which a main controller 16 (display controller) that collectively controls each part of the ophthalmology device 10 is housed. The main controller 16 is supplied with power from a commercial power source (not shown) via the power cable 17a.

The measurement head 20 is a measurement unit that performs an arbitrary subjective test and an arbitrary objective measurement. In the subjective test, a target is displayed on the subject, and the test result is acquired based on the response of the subject to the target. This subjective test includes a subjective refraction measurement such as a distance test, a near test, a contrast test, and a glare test, a visual field test, an astigmatism axis test, and an astigmatism power test. Further, in objective measurement, light is irradiated to the eye to be inspected, and information about the eye to be inspected is measured based on the detection result of the return light. This objective measurement includes a measurement for acquiring the characteristics of the eye to be inspected and an imaging for acquiring an image of the eye to be inspected. Further, for objective measurement, objective refraction measurement (ref measurement), corneal shape measurement (kerato measurement), tonometry measurement, fundus photography, optical coherence tomography (hereinafter referred to as "OCT") are used. There are tomography (OCT photography), measurement using OCT, etc. The measurement head 20 is connected to the main controller 16 via a control / power cable (not shown), and power is supplied via the main controller 16. Also, information transmission / reception between the measurement head 20 and the main controller 16 is performed via this control / power cable.

The measurement head 20 includes a left eye measurement head 20L for acquiring the eye information of the left eye EL of the subject and a right eye measurement head 20R for acquiring the eye information of the right eye ER of the subject. ing. Here, the left eye measuring head 20L and the right eye measuring head 20R have a plane-symmetrical configuration in which the vertical plane located between the two in the X direction is the plane of symmetry.

Further, the left eye measuring head 20L and the right eye measuring head 20R each have a measuring head housing 20a suspended and supported by an arm 14 via a measuring head driving mechanism 20b. Here, the measuring head drive mechanism 20b determines the positions of the measuring head housing 20a in the X direction, the Y direction, and the Z direction, and the orientation centered on the eyeball rotation axis of the eye to be inspected, based on the control command from the main controller 16. change.

Further, a measurement optical system OS for acquiring information of the left eye EL and the right eye ER is built in the measurement head housing 20a.

Further, in both the left eye measurement head 20L and the right eye measurement head 20R, a deflection member 20c is provided on the outer surface of the measurement head housing 20a. The deflection member 20c directs the optical axis irradiated from the observation system 21 described later toward the eye to be inspected, and is configured by a half mirror here.

[Detailed configuration of control system]
As shown in FIG. 2, the main controller 16 has peripheral devices 16a such as a storage unit and an internal memory, and comprehensively controls the operation of the ophthalmic apparatus 10 based on the program stored in the peripheral devices 16a.

A glare light source 22k, a reflex measurement light source 23g, an alignment light source 25a, an alignment light source 26a, and a keratling light source 27b of a measurement optical system OS, which will be described later, are connected to the main controller 16, and these are appropriately turned on and off. Further, in the main controller 16, the operating unit of the measurement optical system OS (image sensor 21 g, display 22a, focusing lens 22e, VCS22h, pinhole plate 22p, reflex light source unit unit 23a, focusing lens 23t, and their drive units). ) Is connected, and these are driven or moved as appropriate.

Further, the measurement head drive mechanism 20b, the moving mechanism of the optometry table 12, the moving mechanism of the arm 14, the examiner controller 19a, the subject controller 19b, and the display device 19c are connected to the main controller 16. ..

Then, the main controller 16 displays an optotype on the display 22a and observes the eye to be inspected according to the operation of the controller 19a for the examiner and the controller 19b for the examinee, and displays the image projected on the image pickup element 21g. The display device 19c is appropriately displayed, and the above-mentioned light sources, operating units, operating mechanisms, and the like are appropriately controlled.

[Detailed configuration of measurement optical system]
The measurement optical system OS shown in FIG. 3 is built in the measurement head housing 20a of the left eye measurement head 20L and the right eye measurement head 20R of the first embodiment, respectively. The measurement optical system OS has the same configuration in both measurement heads 20L and 20R. Therefore, here, the measurement optical system OS built in the measurement head housing 20a of the left eye measurement head 20L will be described.

The measurement optical system OS built in the measurement head housing 20a of the left eye measurement head 20L includes an observation system 21, an optotype projection system 22, an optical power measurement system 23, a first alignment system 25, and a second alignment. It has a system 26 and a kerato system 27. The measurement optical system OS may have a subjective inspection system (cross-cylinder optical system) composed of a set of various lenses used in the subjective inspection.

As shown in FIG. 3, the observation system 21 for observing the anterior segment of the left eye EL (inspected eye) includes an objective lens 21a, a dichroic filter 21b, a half mirror 21c, a relay lens 21d, and a dichroic filter 21e. It has an imaging lens 21f and an imaging element (CCD) 21g. In this observation system 21, the luminous flux reflected by the left eye EL is imaged on the image pickup element 21g by the imaging lens 21f via the objective lens 21a. Therefore, an anterior eye portion image E'projected with the keratling light flux, the light flux of the alignment light source 25a, and the light flux of the alignment light source 26a (bright spot image Br), which will be described later, is formed on the image pickup device 21g. Here, the main controller 16 causes the display device 19c to display the front eye portion image E'and the like based on the image signal output from the image pickup element 21g. Further, a kerato system 27 is provided in front of the objective lens 21a.

The kerato system 27 has a kerato plate 27a and a keratling light source 27b. The kerato plate 27a has a plate shape in which slits concentric with the optical axis of the observation system 21 are provided, and is provided in the vicinity of the objective lens 21a. The keratling light source 27b is provided in line with the slit of the kerat plate 27a. In this kerato system 27, the luminous flux from the lit keratling light source 27b passes through the slit of the kerato plate 27a, so that the keratling light flux for measuring the corneal shape is projected onto the corneal Ec of the left eye EL. The keratling luminous flux is reflected by the corneal Ec of the left eye EL, and is imaged on the image pickup device 21g by the observation system 21. Then, when the image pickup device 21g receives an image of the ring-shaped keratling luminous flux, the main controller 16 causes the display device 19c to display the image of the measurement pattern. Further, the main controller 16 measures the radius of curvature of the corneal shape of the cornea Ec by a well-known method based on the image signal from the image sensor 21g. A first alignment system 25 is provided behind the kerato plate 27a of the kerato system 27.

The first alignment system 25 and the second alignment system 26 perform alignment of the measurement optical system OS with respect to the left eye EL. Here, the first alignment system 25 aligns in the direction (front-back direction) along the optical axis of the observation system 21, and the second alignment system 26 aligns in the direction orthogonal to the optical axis of the observation system 21 (vertical direction, left-right direction). Alignment (direction). The main controller 16 causes the display device 19c to display the alignment mark AL, which is a guideline for the alignment mark, in addition to the anterior eye portion image E'in which the bright spot image Br is formed. The main controller 16 may be configured to start measurement when alignment is completed.

The first alignment system 25 includes a pair of alignment light sources 25a and a projection lens 25b. In the first alignment system 25, the luminous flux from each alignment light source 25a is converted into a parallel luminous flux by each projection lens 25b, and the parallel luminous flux is projected onto the cornea Ec of the left eye EL through the alignment hole provided in the kerato plate 27a. In the main controller 16, the left eye measurement head 20L is moved in the front-rear direction based on the bright spot (bright spot image) projected on the cornea Ec, so that the alignment in the direction along the optical axis of the observation system 21 (front-back direction) is performed. I do. For this alignment in the front-back direction, the position of the left eye measurement head 20L is adjusted so that the ratio of the distance between the two point images by the alignment light source 25a on the image sensor 21g and the diameter of the keratling image is within a predetermined range. conduct.

Further, the second alignment system 26 is provided in the observation system 21. The second alignment system 26 has an alignment light source 26a and a projection lens 26b, and shares a half mirror 21c, a dichroic filter 21b, and an objective lens 21a with the observation system 21. In the second alignment system 26, the luminous flux from the alignment light source 26a is projected onto the cornea Ec of the left eye EL as a parallel luminous flux via the objective lens 21a. In the main controller 16, the left eye measurement head 20L is moved in the vertical direction and the horizontal direction based on the bright spot (bright spot image) projected on the corneal Ec, so that the direction orthogonal to the optical axis of the observation system 21 (up and down). Align in the direction (direction, left and right direction).

The optotype projection system 22 that displays an optotype on the left eye EL is an objective measurement optotype for objectively measuring the eye characteristics of the eye to be inspected, and an objective measurement optotype for subjectively inspecting the eye characteristics of the inspected eye. It is possible to selectively display the subjective optometry target. The optotype projection system 22 includes a display 22a, a half mirror 22b, a relay lens 22c, a reflection mirror 22d, a focusing lens 22e, a relay lens 22f, a field lens 22g, and a variable cross cylinder lens (hereinafter referred to as a variable cross cylinder lens). It has (referred to as “VCC”) 22h, a reflection mirror 22i, and a dichroic filter 22j. Here, the dichroic filter 21b and the objective lens 21a are shared with the observation system 21. Further, since the optotype projection system 22 irradiates the left eye EL with glare light when subjectively inspecting the eye characteristics of the eye to be inspected, the optotype projection system 22 surrounds the optical axis in an optical path different from the optical path leading to the display 22a or the like. The position has at least two glare light sources 22k.

The display 22a is composed of a liquid crystal display (Liquid Crystal Display), an electroluminescence display such as an organic EL, a plasma display, and the like, and displays an arbitrary image based on a control command from the main controller 16. .. The display 22a is movably provided along the optical axis at a position conjugate with the fundus Ef of the left eye EL on the optical path of the optotype projection system 22. The arbitrary image displayed on the display 22a is, for example, an astigmatism target or a punctate target for fixing the line of sight of the left eye EL, and eye characteristics of the left eye EL (visual acuity value, correction power (distance power)). , Near vision), astigmatism axis angle, astigmatism diopter, etc.) ..

Further, in the optotype projection system 22, a through hole of the pinhole plate 22p is provided at a position on the optical path that is substantially conjugated with the pupil of the left eye EL. The pinhole plate 22p is formed by providing a through hole in the plate member to enable insertion of the optotype projection system 22 into the optical path and detachment from the optical path, and when the pinhole plate 22p is inserted into the optical path, the through hole is formed. Position it on the optical axis. By inserting the pinhole plate 22p into the optical path in the subjective test mode, it is possible to perform a pinhole test for determining whether or not the eye E to be inspected can be corrected by the spectacles. In the first embodiment, the pinhole plate 22p is provided between the field lens 22g and the VCS 22h, and is inserted and detached from the optical path based on a control command from the main controller 16. The position where the pinhole plate 22p is provided may be provided at a position on the optical path that is substantially conjugated with the pupil of the left eye EL, and is not limited to the first embodiment.

In the first embodiment, the optical power measuring system 23 for measuring the optical power has a function of projecting a predetermined measurement pattern on the fundus Ef of the left eye EL and a function of detecting an image of the measurement pattern projected on the fundus Ef. And have. The optical power measuring system 23 receives a ring-shaped luminous flux projection system 23A that projects a ring-shaped measurement pattern onto the fundus Ef of the left eye EL and the reflected light of the ring-shaped measurement pattern from the fundus Ef. It has a ring-shaped luminous flux light receiving system 23B.

The ring-shaped luminous flux projection system 23A includes a reflex light source unit unit 23a, a relay lens 23b, a pupil ring diaphragm 23c, a field lens 23d, a perforated prism 23e, and a rotary prism 23f. Here, the dichroic filter 22j is shared with the optotype projection system 22. Further, the dichroic filter 21b and the objective lens 21a are shared with the observation system 21. The refraction light source unit 23a includes, for example, a refraction measurement light source 23g for reflex measurement using a light emitting diode, a collimator lens 23h, a conical prism 23i, and a ring pattern forming plate 23j, which are the main controllers. Based on the control command from 16, the eye refractive power measuring system 23 can be integrally moved on the optical axis.

The ring-shaped light emitting light receiving system 23B includes a hole portion 23p of a perforated prism 23e, a field lens 23q, a reflection mirror 23r, a relay lens 23s, a focusing lens 23t, and a reflection mirror 23u. Here, the objective lens 21a, the dichroic filter 21b, the dichroic filter 21e, the image pickup lens 21f, and the image pickup element 21g are shared with the observation system 21. Further, the dichroic filter 22j is shared with the optotype projection system 22. Further, the rotary prism 23f and the perforated prism 23e are shared with the ring-shaped luminous flux projection system 23A.

[Detailed configuration of astigmatism axis test chart]
FIG. 4 is an explanatory diagram showing the first target of the astigmatism axis test chart in the ophthalmic apparatus of Example 1, and FIG. 5 is an explanatory diagram showing the second target of the astigmatism axis test chart. Hereinafter, the detailed configuration of the astigmatic axis test chart of Example 1 will be described with reference to FIGS. 4 and 5.

The astigmatism axis test chart shown in FIGS. 4 and 5 is a subjective inspection target used when inspecting the inclination angle of the astigmatism axis (hereinafter referred to as “astigmatism axis angle”) caused by the distortion of the cornea or the crystalline lens by the subjective examination. It is a kind. This astigmatic axis test chart is displayed on the display 22a when the astigmatic axis of the eye to be inspected is acquired by a subjective test. Further, in the first embodiment, as the astigmatism axis test chart, the first optotype S1 (see FIG. 4) for acquiring a rough value of the astigmatism axis angle and the angle value acquired by using the first optotype S1 are used as a reference. It has a second optotype S2 (FIG. 5), which is generated as an astigmatic axis angle and obtains a precise value of the astigmatic axis angle.

As shown in FIG. 4, the first optotype S1 has a plurality of omnidirectional directions (360 °) in the radial direction for each predetermined angle (15 °) from the center position O of the optotype display area A where the optotype is displayed. (24) The first radial chart 30 is composed of a plurality of (24) radial lines 31 extending in the dividing direction. In this first optotype S1, the scale 32 is shown at the same time as the radial line 31. The scale 32 is a number from 1 to 12 attached to every other radial line 31, and is displayed at a position near the end of the radial line 31 on the outer side in the radial direction.

As shown in FIG. 5, the second optotype S2 is 1 within a predetermined angle range (30 ° ± 10 °: 20 ° to 40 °) centered on the angle of the reference astigmatic axis (for example, 30 °). The second radial chart 40 is composed of a plurality of (42 in this case) radial lines 41 extending in the direction of dividing into 20 by °. Here, the "reference angle of the astigmatism axis" is the angle of the astigmatism axis acquired by the subjective examination performed using the first radial chart 30 which is the first optotype S1. That is, the second optotype S2 is generated with reference to the angle value acquired by using the first optotype S1, and is deformed according to the result of the inspection using the first optotype S1.

Further, the second optotype S2 enlarges and shows a portion of the plurality of radial lines 41 shown within a predetermined angle range, which is distant from the radiation center position. In the first embodiment, the second optotype S2 is displayed in a circular region B having a predetermined radius centered on the center position O of the optotype display area A on which the optotype is displayed. Further, a scale 42 is shown at the outer peripheral position of the circular region B. The scale 42 has a number indicating the angle of the reference astigmatic axis (here, 30 °) and a number indicating the maximum value (40 °) and the minimum value (20 °) in the predetermined angle range.

Next, the action and effect of the ophthalmic apparatus 10 of Example 1 are described as "operation in the subjective test mode", "high-precision detection action of the astigmatic axis angle", "display action corresponding to the progress of the test", and "display built-in action". Will be explained separately.

[Operation in subjective test mode]
In order to perform a subjective test in the ophthalmic apparatus 10 of the first embodiment, first, the main controller 16 turns on the display 22a in the optotype projection system 22 and causes the display 22a to display an optotype according to the measurement content. As the target for the subjective test, in addition to the astigmatism axis test chart for the astigmatism axis test, for example, a visual acuity chart such as a Randolt ring or a number, a red green chart for the red green test, and a stereoscopic view for the stereoscopic test. There are a test chart, an oblique test chart for an oblique inspection, a chart for an unequal image test, and the like. Next, the main controller 16 moves the focusing lens 22e to a position suitable for the refractive power of the left eye EL objectively measured in advance, and corrects the astigmatic state of the left eye EL objectively measured in advance. Set the VCS22h to the posture to be used.

After displaying the optotype on the display 22a, moving the position of the focusing lens 22e, and setting the posture of the VCS 22h, in this optotype projection system 22, the light beam of the optotype from the display 22a is the half mirror 22b and the relay lens. It is projected onto the fundus Ef of the left eye EL via the 22c, the reflection mirror 22d, the focusing lens 22e, the relay lens 22f, the field lens 22g, the VCS22h, the reflection mirror 22i, the dichroic filter 22j, the dichroic filter 21b, and the objective lens 21a. As a result, the subject can properly visually recognize the optotype displayed on the display 22a.

Then, when the subject visually recognizes the optotype displayed on the display 22a, the examiner or the main controller 16 asks the subject how to see the displayed optotype, and selects the optotype according to the response. By repeating the question, the measured value of the subjective test is determined. In this awareness test mode, when the glare test is performed, the glare light source 22k is turned on based on the control command from the main controller 16 to perform the glare test.

"High-precision detection of astigmatic axis angle"
In the ophthalmic apparatus 10 of the first embodiment, the astigmatism test is performed as described above, but when the astigmatism axis angle is acquired by the astigmatism test, the display 22a displays the astigmatism axis test chart for the astigmatism axis test.

At this time, the main controller 16 first causes the display 22a to display the first optotype S1 shown in FIG. The first optotype S1 acquires a rough value of the visual axis angle, and divides all directions (360 °) in the radial direction into 24 every 15 ° from the center position O of the optotype display area A. It is a first radial chart 30 which consists of 24 radial lines 31 extending in a direction.

Then, the first optotype S1 is displayed on the display 22a, and the first optotype S1 is projected onto the fundus Ef of the left eye EL of the subject, and when the subject visually recognizes the first optotype S1, the main target S1 is displayed. The controller 16 or the examiner asks the subject how to see the first optotype S1, and obtains the astigmatic axis angle of the subject according to the response. The optotype used at this time is the first optotype S1, and the first radial chart 30 composed of radial lines 31 in which all directions (360 °) in the radial direction from the center position O of the optotype display area A is divided into a plurality of directions. Is. Therefore, the astigmatism axis angle that can be acquired is at intervals (15 °) of the plurality of radial lines 31, and the astigmatism axis angle that can be acquired by the subjective test performed using the first optotype S1 is roughly every 15 °. Become a value.

Next, the main controller 16 generates the second optotype S2 (see FIG. 5) with reference to the rough angle value of the astigmatic axis acquired in the subjective test performed using the first optotype S1. That is, 42 lines are divided into 20 at 1 ° within a predetermined angle range (± 10 °) centered on the angle of the astigmatic axis (for example, 30 °) acquired in the subjective test performed using the first optotype S1. A second radial chart 40 consisting of radial lines 41 of the above is generated.

When the main controller 16 generates the second optotype S2, the second optotype S2 is displayed on the display 22a. Then, when the second optotype S2 is projected onto the fundus Ef of the subject's left eye EL and the subject visually recognizes the second optotype S2, the main controller 16 or the examiner gives the subject a second. 2 The appearance of the optotype S2 is asked, and the detailed value of the visual axis angle of the subject is acquired according to the response. The optotype used at this time is the second optotype S2, which is a second radial chart 40 composed of radial lines 41 divided by 1 ° within a predetermined angle range centered on the angle of the reference astigmatic axis. Therefore, the astigmatic axis angle that can be acquired is at intervals (1 °) of the plurality of radial lines 41, and is a more detailed value than the astigmatic axis angle that can be acquired by the subjective test performed using the first optotype S1.

Moreover, in the second optotype S2, only a predetermined range angle centered on the angle of the astigmatic axis acquired by the subjective test performed using the first optotype S1 is displayed. Therefore, this predetermined angle range can be enlarged and shown, and the detailed astigmatic axis angle can be appropriately visually recognized. As a result, the state of the astigmatic axis of the eye to be inspected can be accurately grasped.

Then, in the first embodiment, the first target S1 is a first radial chart 30 composed of a plurality of radial lines 31 extending in the radial direction from the center position O of the display area of the target (target display area A). The second optotype S2 is composed of a plurality of radial lines 41 obtained by dividing a predetermined angle range in the radial direction centered on the angle of the reference astigmatic axis acquired by using the first radial chart 30 at 1 ° intervals. 2 Radial chart 40.

Therefore, it is possible to accurately acquire the detailed value of the astigmatic axis angle, and it is possible to grasp the astigmatic axis angle with high accuracy. Further, since the first optotype S1 has the radial line 41 divided into a plurality of omnidirectional directions (360 °), the subjective inspection in a stationary state without rotating the shape of the astigmatic axis test chart. It can be performed. That is, it is possible to perform an inspection in which the display state of the optotype is kept constant, and the optotype can be appropriately visually recognized over time.

[Display action corresponding to the progress of inspection]
The main controller 16 displays the first optotype S1 at the initial stage of the subjective test for inspecting the astigmatic axis angle. Then, after obtaining a rough angle value of the astigmatic axis angle by a subjective test using the first optotype S1, the optotype displayed on the display 22a is switched from the first optotype S1 to the second optotype S2. The second optotype S2 is displayed in the second stage of the subjective examination. That is, the main controller 16 switches the optotype displayed on the display 22a as the subjective examination progresses. Moreover, since the first optotype S1 and the second optotype S2 are displayed by the display 22a capable of displaying an arbitrary image, they can be easily switched.

As a result, in the astigmatism test for acquiring the astigmatism state (astigmatism axis angle), it is possible to display the optotype according to the accuracy of the astigmatism state to be acquired, and it is possible to carry out a smooth astigmatism test.

[Display built-in action]
In the ophthalmic apparatus 10 of the first embodiment, a display 22a for displaying an astigmatic axis test chart for astigmatic axis inspection is built in the measuring head housing 20a of the measuring head 20. Therefore, the ophthalmic apparatus 10 can be miniaturized and the installation space can be saved. In addition, a space can be provided in front of the subject, and the subject can be prevented from feeling oppressive.

(Example 2)
In the second embodiment, the first optotype, which is an astigmatism test chart, is a first parabola chart composed of a pair of parabolas arranged line-symmetrically in the optotype display area, and the second optotype is a first optotype. This is an example of a second parabolic chart which is an optotype for acquiring the astigmatic power generated by the use. Hereinafter, the detailed configuration of the astigmatism test chart of Example 2 will be described with reference to FIGS. 6 and 7.

The first optotype S1A of the second embodiment is a kind of subjective inspection optotype used when inspecting the tilt angle of the astigmatic axis (hereinafter referred to as “astigmatic axis angle”) by the subjective inspection, and is as shown in FIG. The astigmatism is displayed in the circular area B having a predetermined radius centered on the center position O of the astigmatism display area A. The first parabola S1A is a first parabola chart 50 composed of a horizontal straight line L1 displayed in the circular region B and a pair of parabolas 50a and 50b. Here, the horizontal straight line L1 is a straight line that passes through the center position O of the optotype display area A and extends in the horizontal direction in the optotype display area A. Further, the pair of parabolas 50a and 50b are a pair of axisymmetric parabolas having an orthogonal straight line L2 passing through the center position O of the optotype display region A and orthogonal to the horizontal straight line L1 as a symmetric line.

One parabola 50a is a curve connecting one end of the horizontal straight line L1 and the intersection K1 of the dividing line of the circular region B and the intersection K2 of the orthogonal straight line L2 and the dividing line of the circular region B. The other parabola 50b is a curve connecting the intersection K3 between the other end of the horizontal straight line L1 and the dividing line of the circular region B and the intersection K2 between the orthogonal straight line L2 and the dividing line of the circular region B. Since the pair of parabolas 50a and 50b may be line-symmetrical, the curvature is arbitrarily set.

Then, the first optotype S1A is displayed at the initial stage (when the astigmatism axis angle is acquired) at the time of the subjective examination for inspecting the astigmatism state. Further, the first optotype S1A is displayed while rotating in a certain direction about the center position O of the optotype display region A during the inspection of the astigmatic axis angle. Here, when the first optotype S1A is viewed with astigmatic eyes, a "dark part" appears somewhere on the pair of parabolas 50a and 50b, and the others appear blurry. The astigmatic axis angle that can be obtained by using the first optotype S1A is such that by rotating the first optotype S1A, the "deep feeling portion" visually recognized on the pair of parabolas 50a and 50b is the intersection K2. It is shown by the horizontal straight line L1 when it is distributed in a well-balanced manner around.

That is, the first optotype S1A is displayed on the display 22a, and the first optotype S1A is visually recognized by the subject. Then, the first optotype S1A displayed on the display 22a is rotated in the left direction (the same direction as the movement of the hands of the clock). If admitted, continue to rotate the first optotype S1A as it is. As a result, the "dark feeling part" gradually heads toward the intersection K2, and the "dark feeling part" appears near the intersection K2 of the parabola 50b on the right side. The direction indicated by the horizontal straight line L1 when the "feeling dark portion" on both parabolas 50a and 50b has the same length near the intersection K2 is the direction of the astigmatism axis.

On the other hand, the second optotype S2A of the second embodiment is a kind of subjective inspection optotype used when the intensity of astigmatism (hereinafter referred to as “astigmatism power”) is inspected by the subjective test, and is as shown in FIG. The astigmatism is displayed in the circular area B having a predetermined radius centered on the center position O of the astigmatism display area A. The second target S2A is a second parabola chart 51 having a first parabola chart 50α and a second parabola chart 50β displayed in the circular region B.

Here, the first parabolic chart 50α rotates a parabolic chart showing the angle of the reference turbulent axis acquired by the subjective test using the first optotype S1A by a predetermined angle (for example, 20 ° clockwise). It is a parabolic chart. Further, the second parabola chart 50β is a rotation of a parabola chart showing the angle of the reference astigmatic axis acquired in the subjective test performed using the first optotype S1A by a predetermined angle (for example, 35 ° counterclockwise). It is a parabolic chart that was made to. The direction of the reference astigmatism axis is indicated by the axis J of the alternate long and short dash line. That is, the second parabola chart 51 constituting the second optotype S2A is generated with reference to the angle value acquired by using the first optotype S1A, and is an inspection using the first optotype S1A. Deforms according to the result of.

Then, the second optotype S2A is displayed in the second stage (when the astigmatic power is acquired) at the time of the subjective examination for inspecting the astigmatic state. Further, in the second optotype S2A, the first parabola chart 50α and the second parabola chart 50β are simultaneously displayed so as to sandwich the direction orthogonal to the angle of the reference astigmatism axis without rotating.

In order to acquire the astigmatic dioptric power of the eye to be inspected using the second optotype S2A, the astigmatic axis angle of the eye to be inspected is acquired in advance using the first optotype S1A. Next, the axis of the corrected concave cylindrical lens is aligned with the acquired astigmatic axis angle, and the lens is mounted in front of the eye to be inspected. In the main controller 16, the second optotype S2A is displayed on the display 22a in that state. Then, when the subject is made to visually recognize the second optotype S2A, he / she is asked whether or not the "deep feeling part" can be visually recognized on the first and second parabolic charts 50α and 50β.

At this time, if the first and second parabolic charts 50α and 50β are all uniform in density and no shading is observed, the degree of the concave cylindrical lens used for the correction is correct. On the other hand, when a "deep feeling part" is recognized in any of the first and second parabolic charts 50α and 50β, it is asked which of the left and right parabolas has a "deep feeling part". If a "deep feeling" is found on the parabola near the axis J, which indicates the direction of the reference astigmatism axis, the degree of the corrected concave cylindrical lens is increased. Further, when a "part that feels dark" is recognized on a parabola far from the axis J indicating the direction of the reference astigmatism axis, the degree of the corrected concave cylindrical lens is weakened. Then, after fixing the "axis" of the straightening concave cylindrical lens and changing the "degree", the same operation is repeated again to determine the degree of the straightening concave cylindrical lens.

As described above, the second optotype S2A is generated with reference to the angle value of the astigmatism axis acquired by using the first optotype S1A, and the display of the display 22a is switched to such a second optotype S2A for astigmatism. Check the condition (astigmatism power). Therefore, the display of the display 22a can be switched according to the progress of the examination, and the astigmatism state of the eye to be inspected can be accurately grasped. In particular, in the second embodiment, since the second optotype S2A is an optotype for acquiring the astigmatic dioptric power, the astigmatic axis angle of the eye to be inspected can be accurately acquired.

Moreover, at this time, the second parabola chart 51, which is the second optotype S2A, has a plurality of (two) parabola charts (first parabola chart 50α, second parabola chart 50β) having different rotation angles. The two parabolic charts 50α and 50β can be displayed at the same time. Therefore, the two parabolic charts 50α and 50β can be easily compared, and the subject answers the appearance more accurately than, for example, when the two parabolic charts 50α and 50β are displayed alternately. be able to. As a result, it is possible to obtain a more accurate astigmatic power.

Although the ophthalmic apparatus of the present invention has been described above based on Examples 1 and 2, the specific configuration is not limited to these Examples, and each claim is within the scope of the claims. Design changes and additions are permitted as long as they do not deviate from the gist of the invention.

For example, in the first embodiment, the first optotype S1 is a first radial chart 30 composed of a plurality of radial lines 31, and the second optotype S2 is an angle of an astigmatic axis acquired by using the first radial chart 30. An example is shown in which the second radial chart 40 is composed of a plurality of radial lines 41 in which a predetermined angle range in the radial direction centered on the above is divided in detail. Further, in the second embodiment, the first target S1A is a first parabolic chart 50 composed of a pair of parabolas 50a and 50b, and the second target S2A is a parabolic axis acquired by using the first parabola chart 50. An example is shown as a second parabola chart 51 including a first parabola chart 50α showing an angle and a second parabola chart 50β obtained by rotating the first parabola chart 50α by a predetermined angle. However, the present invention is not limited to this, and the first optotype is an optotype that acquires the angle of the astigmatic axis of the eye to be inspected, and the second optotype obtains the angle value of the astigmatic axis acquired by using the first optotype. Any optotype generated as a reference may be used. Further, the characteristic of the eye to be inspected acquired by the second optotype may be an astigmatic axis angle, an astigmatic dioptric power, or other eye characteristics.

That is, the first optotype S1A is the first parabola chart 50 composed of a pair of parabolas 50a and 50b as shown in the second embodiment, and the second optotype S2B is the first parabola chart 50 as shown in FIG. The enlarged chart 52 may be enlarged and displayed in a predetermined range including the above "part K that feels dark". In this case, after displaying the enlarged chart 52, the subject can visually observe the astigmatism axis angle while rotating the enlarged chart 52 in a predetermined direction, so that the astigmatism axis angle can be observed in detail.

Further, in Example 2, an example is shown in which the second optotype S2B is configured by a second parabola chart 51 having a plurality of (two) parabola charts 50α and 50β. However, the second parabola chart 51 may be a parabola chart obtained by rotating a parabola chart showing the angle of the reference turbulent axis acquired by the subjective test using the first optotype S1A by a predetermined angle. For example, only the first parabola chart 50α may be obtained by rotating the parabola chart showing the reference parabolic axis by 20 ° clockwise.

Further, the first optotype is a first radial chart composed of a plurality of radial lines, and the second optotype is a parabola obtained by rotating a parabola chart showing the angle of the astigmatic axis acquired by using the first radial chart by a predetermined angle. It may be a chart. That is, the first optotype may be a radial chart and the second optotype may be a parabolic chart.

Further, as the first optotype S1 shown in the first embodiment, a radial chart may be used in which at least one of the plurality of radial lines is shown in clear black and the remaining radial lines are shown in light gray. In this case, the angle of the astigmatic axis is observed by rotating the first optotype S1. Then, the second optotype S2 may be generated with reference to the angle value of the astigmatic axis obtained as a result.

Further, in the first embodiment, when the second optotype S2 is generated, the range of ± 10 ° with respect to the angle value of the reference astigmatism axis acquired by the subjective test using the first optotype S1 is “predetermined”. Specified in "angle range". However, the present invention is not limited to this, and the "predetermined angle range" can be arbitrarily set as long as it is a predetermined range based on the angle value of the astigmatic axis acquired by using the first optotype.

Further, in the first optotypes S1, S1A and the second optotypes S2, S2A, the display state of the shape, thickness, line type, number of displays, etc. of the radial line or parabola is determined according to the state and appearance of the eye to be inspected. May be adjusted. As a result, each optotype can be appropriately displayed according to the eye to be inspected, and more accurate observation results can be obtained. Further, in any case, the astigmatic state of the eye to be inspected is observed in detail by using the second visual targets S2 and S2A based on the angle value of the astigmatic axis acquired by using the first visual targets S1 and S1A. be able to.

10 Ophthalmology equipment 16 Main controller (display controller)
20 Measurement head 20L Left eye measurement head 20R Right eye measurement head 20a Measurement head housing 20b Measurement head drive mechanism OP Measurement optical system 21 Observation system 22 Objective projection system 22a Display S1 First optotype S2 Second optotype 30 First radial Chart 31 Radial line 32 Scale 40 Second radial chart 41 Radial line 42 Scale A Optical target display area B Circular area

Claims (3)

It is equipped with a display provided on the optical axis of the target projection system that displays the target on the eye to be inspected, and a display controller that controls the display content of the display.
The display is arranged inside a measurement head housing containing a measurement optical system for acquiring information on the eye to be inspected.
The display controller has a first optotype that causes the display to acquire the angle of the astigmatic axis of the eye to be inspected, and a second optotype generated based on an angle value acquired by using the first optotype. Switch and display,
The first optotype has a plurality of radial directions extending from the center position of the optotype display area displaying the first optotype and the second optotype in a direction in which all directions in the radial direction are divided into a plurality of portions at predetermined angles. The first radial chart consisting of lines
The second optotype divides in detail a predetermined angle range in the radial direction centered on the angle of the astigmatic axis acquired by using the first radial chart, and a plurality of radial lines symmetrical with respect to the radial center position. An ophthalmic apparatus characterized by having a second radial chart consisting of. In the ophthalmic apparatus according to claim 1,
The second optotype is an ophthalmic apparatus characterized in that, of a plurality of radial lines shown in the predetermined angle range, a portion distant from the radiation center position is enlarged. In the ophthalmic apparatus according to claim 1 or 2.
An ophthalmic apparatus characterized in that, in the optotype display area, a scale is displayed at a position near the end of the radial line on the outer side in the radial direction.

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