JP7147276B2 - Ophthalmic measuring device - Google Patents

Description

The present disclosure relates to an ophthalmic measurement device that measures multiple types of eye characteristics.

2. Description of the Related Art Conventionally, ophthalmologic measurement apparatuses for measuring a plurality of types of eye characteristics have been known.

As a device of this type, for example, Patent Document 1 discloses a composite device of a keratometer and a tonometer. In Patent Literature 1, a keratometry index projection portion is formed on the front surface of one of the units. and corneal shape can be measured.
JP 2016-214466 A

In recent years, information about corneal asphericity has become more and more important for prescriptions such as IOL prescriptions, contact lens prescriptions, and corrective lenses in orthokeratology. For example, in IOL prescription, it is considered that the distribution information of the shape on the cornea with a diameter of at least 6 mm is necessary, and in contact lens prescription and corrective lens prescription in orthokeratology, a wider range of distribution information is required. It is considered.

However, the device described in Patent Document 1 lacks a measurement range on the cornea, and furthermore, shape distribution information cannot be obtained. Therefore, the inventors of the present application have studied an apparatus configuration capable of measuring corneal shape distribution information over a wide range on the cornea.

The present disclosure has been made in view of the above circumstances, and a technical problem thereof is to satisfactorily obtain corneal shape distribution information.

An ophthalmologic measurement apparatus according to a first aspect of the present disclosure includes an intraocular pressure measurement unit that has a distal end and measures the intraocular pressure of the eye to be examined with the distal end approaching the cornea of the eye to be examined; A plate-shaped index projector having a window exposed to the side of the eye to be examined and projecting a pattern index for measuring the shape of the cornea onto the cornea of the eye to be examined; a moving unit that moves the distal end portion in the front-rear direction relative to the index projector; and a measurement mode that switches between a corneal shape measurement mode for measuring corneal shape and an intraocular pressure measurement mode for measuring intraocular pressure. and a control unit for switching, wherein the control unit controls the moving unit according to the measurement mode, thereby switching the distal end portion of the intraocular pressure measurement unit to the index projector in the intraocular pressure measurement mode. It is arranged at the first position on the side of the subject's eye with respect to the surface, and is arranged at the second position which is retracted from the front first position in the corneal topography measurement mode.

An ophthalmologic measurement apparatus according to a second aspect of the present disclosure includes a plate-shaped index projector that projects a pattern index for measuring a corneal shape onto the cornea of the subject's eye, and a plate-shaped index projector that faces the subject's eye in the same direction as the index projector. an intraocular pressure measurement unit having opposing tips and measuring the intraocular pressure of the subject's eye with the tips approaching the cornea of the subject's eye, and forming the pattern index on the index projector. The tip portion is arranged closer to the central portion of the index projector than the outermost pattern area among the pattern areas for the index projector.

An ophthalmologic measurement apparatus according to a third aspect of the present disclosure, as a pattern index for measuring a corneal shape, has a shape on a first circumference having a first diameter, or a shape distribution inside the first circumference. and a second pattern index for measuring the shape distribution inside a second circumference larger than the first diameter, projected onto the cornea of the eye to be examined. projection means; detection means for detecting the corneal reflected light of the first pattern index or the second pattern index projected from the index projector as an index image; and analyzing the index image to determine the shape of the cornea. an analysis means for acquiring information; a first corneal topography measurement mode for acquiring shape information of the cornea based on the first pattern index; and a second corneal shape for acquiring shape information of the cornea based on the second pattern index. a control means for selecting a measurement mode between the measurement modes, and selectively projecting one of the first pattern index and the second pattern index onto the eye to be inspected from the index projection means in accordance with the selected measurement mode; and have

According to the present disclosure, corneal shape distribution information can be obtained satisfactorily.

FIG. 2 is a side view of the ophthalmologic measurement device of the embodiment, showing the device position when in the corneal topography measurement mode and the eye refractive power measurement mode; Fig. 2 is a side view of the ophthalmologic measurement device of the embodiment, showing the device position when in the tonometry mode; FIG. 10 is a front view of the placide plate according to the example as viewed from the subject's eye side in the corneal topography measurement mode of the example; FIG. 10 is a front view of the placide plate according to the example as viewed from the subject's eye side in the intraocular pressure measurement mode of the example; 1 is a block diagram showing an electrical configuration in an ophthalmologic measurement apparatus of an embodiment; FIG. FIG. 11 is a partial front view of a placido unit according to a modification; It is the figure which looked at the placide unit which concerns on a modification from the side in the corneal topography measurement mode. It is the figure which looked at the placide unit which concerns on a modification from the side in the intraocular pressure measurement mode.

"Overview"
Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. An ophthalmologic measurement apparatus according to each embodiment measures corneal shape and a plurality of other ocular characteristics. For convenience, the ophthalmologic measurement apparatus will be referred to as the "apparatus" in the following description.

The apparatus includes at least an index projector and one or more measurement units (see Figures 1-4). Preferably, the device may have more than one measuring unit. In this embodiment, one measuring unit is used for measuring at least one ocular characteristic. Eye characteristics may be measured optically or by non-optical methods. When a plurality of measurement units are provided, each measurement unit may measure different eye characteristics.

In the following description, the portion of the apparatus that faces the subject's eye and measures the eye characteristics may be referred to as a measurement section. The measurement section includes an index projector and each measurement unit. In each measurement unit, the tip portion on the side of the subject's eye is referred to as the tip portion in the following description.

Moreover, hereinafter, unless otherwise specified, the present apparatus will be described as having two measurement units, a first measurement unit and a second measurement unit. Each of the first measurement unit and the second measurement unit is provided with an optical system for measuring eye characteristics different from the corneal shape. However, at least one of the first measurement unit and the second measurement unit may include part of an optical system that measures the corneal shape.

In addition, the device may further have a control unit (see FIG. 5). The controller is a kind of processor and controls at least the measurement operation in this device. Further, it may control various devices such as various actuators and monitors provided in the apparatus.

The first measuring unit and the second measuring unit each have a measuring axis (see FIGS. 1-4). The measurement axis is the axis along which the subject's eye should be positioned during measurement. The measurement axis may be an axis substantially perpendicular to the measurement point (or imaging plane). For example, the measurement axis may be the axis along the working distance direction of the device. The measurement axis of the first measurement unit (referred to as first measurement axis) and the measurement axis of the second measurement unit (referred to as second measurement axis) are arranged in parallel in the vertical and horizontal directions. For example, the first measurement axis and the second measurement axis may be arranged substantially parallel.

In this embodiment, the eye characteristics measured by each measurement unit may be, for example, eye refractive power, intraocular pressure, corneal thickness, eye axial length, and others.

A fiducial projector is utilized to measure the corneal shape. The front surface (front surface) of the index projector is arranged to face the subject's eye. The index projector projects a pattern index suitable for measuring the shape of the cornea from the front of the index projector onto the cornea of the subject's eye.

The pattern index may then be formed by divergent light. In that case, various surface emitting devices may be applied as the index projector.

Moreover, in the embodiment, the index projector may be formed in a plate shape. The plate-shaped index projector may be disc-shaped, for example. In the case of the disc type, the surface of the index projector is formed in a plane shape or a bowl shape. A cone type projector is also known as an index projector. Although the cone type can be formed in a smaller size, it is disadvantageous in that it has a short working distance and a narrow tolerance for alignment in the working distance direction. A disk-shaped, surface-emitting index projector may, for example, comprise a placido plate. Also, a liquid crystal panel, an organic EL panel, or the like can be used instead of the platide plate.

The pattern index projected from the index projector may be formed, for example, by a concentric multiple ring pattern (see FIGS. 3 and 4). Each ring indicator may be formed as an unbroken continuous ring. In addition, if there are at least three measurement points on the same circumference, curvature information on the circumference can be obtained. Therefore, a point index or an intermittent ring index having three or more measurement points may be used. . However, the pattern of the index used for measurement is not limited to this, and may be a grid pattern, a spider web pattern, or a dot matrix pattern. or other patterns.

The index projector may be capable of selectively projecting any portion of the pattern index. Also, the pattern index does not have to be uniquely determined in the index projector, and for example, it may be possible to project a plurality of pattern indices that are different from each other.

The device may further comprise an anterior segment imaging optical system. The anterior segment imaging optical system captures a front image of the anterior segment. In this embodiment, information about the shape of the cornea is obtained based on the front image captured with the pattern index projected. More specifically, information about the shape of the cornea is obtained by analyzing the image of the pattern index included in the front image. The anterior segment imaging optical system may be housed in one of the first measurement unit and the second measurement unit, for example. In this case, it is desirable that one of the first measurement axis and the second measurement axis corresponding to the measurement unit accommodating the anterior eye imaging optical system is coaxial with the optical axis of the anterior eye imaging optical system. Further, the anterior segment front image captured by the anterior segment imaging optical system may be used as an observation image for alignment between the measuring section and the subject's eye. A corneal bright spot or the like may also be used for alignment. A corneal bright spot may be formed, for example, by index light projected from an alignment optical system.

For example, as shown in FIGS. 3 and 4, a window may be formed on the front surface of the index projector. A window is formed corresponding to each of the first measurement axis and the second measurement axis. Each window is passed through by a measurement axis corresponding to each window. The window forms a path through which the tip of each unit itself or the optical axis passes. The window through which the tip passes may be formed by at least one of an opening and a notch, for example. The window through which the optical axis passes may be formed of an opening, a notch, or a translucent member.

The tip of each measurement unit may protrude through the window toward the subject's eye from the surface of the index projector, or may protrude (see FIGS. 1 and 2). At this time, the amount of protrusion of the tip portion may be changeable. For this purpose, for example, a moving section may be provided that moves (displaces) the tip of at least one of the measurement units in the front-rear direction with respect to the surface of the index projector. Although the details will be described later, by retracting the tip of a measurement unit when the measurement unit is not in use, the tip does not interfere with the measurement of other eye characteristics or the movement of the device.

Hereinafter, the window corresponding to the first measurement axis will be referred to as the first window, and the window corresponding to the second measurement axis will be referred to as the second window. Either the first window portion or the second window portion may be formed in a region corresponding to the corneal vertex in the index projector (for example, the central portion of the index projector). As described above, since the gradient near the corneal vertex can be considered to be known (substantially zero), even if the window is arranged, it has little effect on obtaining shape information of the cornea.

An eye measurement is performed with each measuring unit via a measuring axis that passes through the index projector. The measurement axis used for corneal topography measurement may be coaxial with either the first measurement axis or the second measurement axis, or may be a third measurement axis different from either of them.

The device may further comprise a drive. The drive unit adjusts the positional relationship between the measurement unit and the subject's eye in vertical and horizontal directions. Thereby, the subject's eye can be selectively arranged on each measurement axis. The drive unit is used to change the eye characteristics measured in the measurement unit. In addition, the drive unit may also be used for alignment adjustment with respect to the subject's eye.

Here, in this embodiment, it is conceivable to arrange each measurement unit such that at least one of the first measurement axis and the second measurement axis is arranged outside the index projector. Such an arrangement would tend to limit the size of the index projector. In contrast, in this embodiment, both the first measurement axis and the second measurement axis pass through the index projector. This makes it easier to increase the size of the index projector. As a result, a wider range of corneal shapes can be measured satisfactorily. In addition, it becomes easy to miniaturize the drive unit and the like. That is, it is advantageous for space saving of the device.

<Interpolation of pattern index>
However, it is conceivable that the pattern index may be missing due to the formation of the two windows on the index projector. Areas lacking pattern indices are disadvantageous in obtaining shape information of the cornea. In addition, in the present embodiment, either one of the first measurement axis and the second measurement axis must be away from the region corresponding to the corneal vertex in the index projector (for example, the center of the index projector). It will pass through the position. Missing pattern indicators due to such measurement axes can be particularly disadvantageous. Therefore, in the present embodiment, missing pattern indices may be interpolated.

The following are examples of means for interpolation.

<Interpolation Index Projector>
For example, the device may have an interpolating index projector. The interpolating index projector projects the part of the pattern index missing by the window onto the cornea. The interpolating index projector may be, for example, a partial placido. Alternatively, a liquid crystal panel, an organic EL panel, or the like may be used. Similar to the index projector, the interpolating index projector is also preferably a device that forms part of the pattern index by planar emission.

The interpolation index projector may be a member that can be inserted into and removed from the window (see FIGS. 3 and 4). In this case, the control section of the apparatus may perform insertion/removal control of the interpolation index projector with respect to the window section. The insertion/removal control may be linked with the selection of the measurement mode. For example, the controller may select a measurement mode between a corneal topography measurement mode for measuring the corneal topography and a second measurement mode for measuring the first eye characteristic or the second eye characteristic. At this time, the controller may insert the interpolating index projector into the window in the corneal topography measurement mode, and retract it from the window in the second measurement mode.

The interpolating index projector has a plane that intersects the surface of the index projector in the vicinity of the window, and projects a part of the pattern index that is missing due to the window onto the cornea from that plane. (See FIGS. 6A, 6B and 6C). The plane of the interpolating index projector is formed so as not to intersect the measuring axes of the first measuring unit and the second measuring unit. For example, it may be formed parallel to the measurement axis. Furthermore, it is desirable that the surface of the interpolating index projector be formed within a range that does not interfere with the projection of the pattern index from the index projector.

Also, the interpolation index projector may be provided in either the first measurement unit or the second measurement unit. For example, an interpolating index projector may be provided at the tip of each unit exposed from the window. Further, an interpolation index projector may be provided as part of the optical system arranged inside the housing of each unit.

<Switching the region where the pattern index is projected on the cornea>
Moreover, in order to interpolate a portion of the pattern index that is missing due to the window, the pattern index may be projected from the index projector by switching the region on which the pattern index is projected on the cornea. For example, the orientation of the line of sight with respect to the index projector may be switched between a first orientation and a second orientation, and the pattern index may be projected in each orientation to perform corneal shape measurement. Since the corneal area corresponding to the missing pattern index in one direction is projected with the pattern index in the other direction, the measurement result corresponding to the missing pattern index in one direction is interpolated from the measurement result in the other direction. can. Interpolation is easier if the first and second orientations are known.

<Small window>
The index projector projects a plurality of indices onto the cornea from each of the plurality of index projection locations to form pattern indices. For example, in a placide plate, ring-shaped light-transmitting portions and light-shielding portions are formed concentrically and alternately on the front surface of the placide plate.

A window corresponding to each of the first measurement axis and the second measurement axis may be formed in a gap between a certain index projection point and an adjacent index projection point. For example, in the case of the placide plate described above, the window may be formed in a size that fits in the light shielding portion. In this case, missing pattern indices are suppressed. Also, if the size of the window required for one measurement unit is larger than one gap, the window may be divided into a plurality of gaps. For example, in the case of an intraocular pressure measurement unit, a window for corneal applanation and a window for applanation detection may be formed in separate gaps.

<Switching measurement area on cornea>
In this apparatus, the pattern index projected from the index projector may be changed, so that the measurement area on the cornea may be changed according to the pattern index projected from the index projector.

<Switching between Topo mode and Kerato mode>
For example, a measurement mode in corneal topography measurement may be selected by the controller between keratomode and topomode. The control unit may select the first topo mode and the second topo mode according to an operation input by the examiner. In keratomode, the corneal shape at a single circumferential region on the cornea may be measured. The index projector projects indices onto at least three points on the circumferential area. Of course, a ring-shaped index may be projected. As the analysis result (measurement result) of the index image detected from the front image of the anterior segment in this state, for example, the radius of curvature of the cornea, the refractive value, the principal meridian of the cornea, and the amount of corneal astigmatism in a circumferential region of a predetermined radius. etc., at least one of them is obtained. For example, one or both of a circumferential area with a diameter of 3.3 mm and a circumferential area with a diameter of 2.4 mm may be measured. In this case, the controller projects the index from the index projector onto one or both of the two circumferential regions.

In topomode, corneal topography is measured. For example, the measurement area may be an area on the cornea with a diameter of at least 6 mm. In this case, for example, three or more indicators (of course, ring indicators may be used) are projected onto at least four or more circumferential areas having different diameters within a diameter of 6 mm. As an analysis result of the target image detected from the front image of the anterior segment in this state, for example, distribution information of the corneal shape in the measurement region is obtained. Any one of elevation, curvature, and corneal refractive power may be acquired as the distribution information.

The keratomode is a more suitable mode for screening corneal malformations and the like. For example, analysis results can be obtained in a shorter time because the measurement area is limited compared to topomode. Moreover, when the pattern index is visible light, the subject feels less glare due to the projection of the pattern index, and the burden is low. On the other hand, in the topo mode, since detailed shape information of the cornea can be obtained, it is highly useful in situations such as diagnosis of corneal shape abnormality, IOL prescription, refractive correction, and the like.

Therefore, the examiner can selectively use two measurement modes, the topo mode and the kerato mode, according to the purpose of use.

Further, the present apparatus may be capable of performing continuous measurement in which kerato mode measurement and topo mode measurement are continuously performed under predetermined conditions. In continuous measurement, first, a measurement in keratomode is performed. It is then determined whether topometry should be performed based on the results of the keratometry measurements. For example, in the determination process, the keratomode measurement results (eg, confidence factor, radius of curvature, etc.) are compared to thresholds. The threshold may be, for example, a threshold for corneal malformation. For example, a reliability coefficient indicating the deviation (deviation in each meridian direction) between the ring index image and the recent ellipse for the ring index image detected from the frontal image of the anterior segment is obtained. A determination may be made by comparing to a threshold. If the greater the deviation, the greater the value of the confidence factor, measurements in topo mode may be performed automatically when the confidence factor exceeds a predetermined threshold. Also in this case, measurements in topo mode are not performed if the confidence factor is less than or equal to a predetermined threshold. If continuous measurements are taken, both keratomode and topomode measurements may be displayed simultaneously or alternatively on the monitor. Alternatively, only one of them may be output. In the above-described continuous measurement, on the premise of rapid measurement in the keratomode and low burden on the subject, measurement in the topo mode is automatically performed as necessary, so corneal examination can be performed efficiently. can.

Also, when comparing the radius of curvature with a threshold value, about 7.8 mm is known as an average value of the radius of curvature, and the threshold value may be appropriately set to a value lower than this value. It is considered that the radius of curvature differs depending on the age of the subject. Therefore, the control unit may, for example, acquire age information in advance based on an input operation of the examiner or the like, and may perform comparison with the measured value using a threshold corresponding to age. In this case, if the radius of curvature is below the threshold, topo-mode measurements may be automatically performed, and if the radius of curvature is greater than or equal to the threshold, no topo-mode measurements may be performed.

<Switching between 1st topo mode and 2nd topo mode>
The control unit may select a measurement mode in corneal topography measurement, for example, between a first topo mode and a second topo mode. The control unit may select the first topo mode and the second topo mode according to an operation input by the examiner.

The first topo-mode and the second topo-mode have different measurement regions. In the present embodiment, in the second topo mode, the area inside the circumference having a larger diameter than in the first topo mode is used as the measurement area. For example, the measurement area of the first topomode is, for example, an area within 6 mm in diameter suitable for IOL prescription, and the measurement area of the second topomode is an area within 10 mm in diameter suitable for orthokeratology, contact lens prescription, etc. There may be. The measurement area of the second topomode includes the measurement area of the first topomode, but in both modes, the first topomode is better in terms of the analysis time and the burden on the subject when the pattern index is visible light. Since it is advantageous, it is preferable for the examiner to use the two properly.

Note that when the window is formed at a position away from the center of the index projector, at least one of the keratomode and the first topo mode is projected inside the window (the central portion) of the index projector. and at least one of the topo-mode and the second topo-mode may project the pattern index from both the inside of the window and the outside of the window.

In the case where pattern indices are projected both inside and outside the window, the control unit may interpolate missing pattern indices due to the window by the various methods described above. .

<Switching to intraocular pressure measurement mode>
Any one of the measurement units of this device may be an intraocular pressure measurement unit that measures intraocular pressure as an eye characteristic. In this case, the index projector and the distal end of the tonometry unit face the subject's eye in the same direction. Then, the front end portion is located closer to the center of the index projector than the outermost pattern area (for example, the pattern area indicated by reference numeral 205 in FIG. 3) among the pattern areas for forming the pattern index in the index projector. may be placed. In the above description, by forming a window in the index projector, the tip portion is arranged closer to the central portion of the index projector than the outermost pattern area. However, in realizing such an arrangement, it is not always necessary to form the window. For example, when the index projector has a shape elongated in one direction, the tip may be arranged in a direction intersecting the one direction and outside the index projector.

Also, the controller can switch the measurement mode of the device between a corneal topography measurement mode and an intraocular pressure measurement mode. In the tonometry mode, the intraocular pressure is measured by the tonometry unit, and in the corneal topography mode, the corneal shape is measured based on the pattern index from the index projector.

The tonometry unit may have an applanation section and an applanation detection section. The applanation part applanates the cornea of the subject's eye in one direction. The applanation detector detects an applanation signal associated with the applanation action of the applanator. An intraocular pressure is obtained based on the applanation signal.

The intraocular pressure measurement method by the intraocular pressure measurement unit may be a non-contact type or a contact type. The non-contact type may be a method of spraying fluid (for example, compressed air) onto the cornea and detecting deformation of the cornea. Alternatively, a method of irradiating ultrasonic waves in a non-contact manner instead of a fluid may be used.

Compared to corneal shape measurement using a pattern index from an index projector, intraocular pressure measurement tends to shorten the working distance, which is the distance between the device and the subject's eye, and the tip of the tonometry unit can be brought closer to the cornea. measurement is easy to perform. For this reason, it is thought that the tip of the tonometry unit needs to protrude from the surface of the index projector when measuring tonometry. However, when the pattern index is projected onto the cornea from the index projector as it is, part of the pattern index may be blocked by the tip of the tonometry unit.

Therefore, the apparatus may have, for example, a moving section that moves (displaces) the distal end portion of the intraocular pressure measurement unit in the front-rear direction with respect to the surface of the index projector. For example, the moving section may move the entire intraocular pressure measurement unit in the front-rear direction with respect to the index projector. In addition, when there is another measurement unit other than the intraocular pressure measurement unit, the distal end portion of the intraocular pressure measurement unit may be movable in the front-rear direction with respect to the other measurement unit by the moving section. In this case, the index projector and the further measuring unit may be fixedly arranged. Of course, the other measuring units (more particularly at least the tip) may also be movable back and forth with respect to the surface of the index projector.

The control unit controls the moving unit in accordance with the measurement mode so that the distal end portion of the intraocular pressure measurement unit is placed at the first position on the subject's eye side with respect to the surface of the index projector in the intraocular pressure measurement mode. good too. Then, in the corneal topography measurement mode, the distal end portion of the tonometry unit may be arranged at a second position that is retracted from the first position. Preferably, in the corneal topography measurement mode, the tip of the tonometry unit may be retracted from the surface of the index projector. By retracting the distal end portion of the tonometry unit during corneal shape measurement, it is possible to prevent the distal end portion from interfering with corneal shape measurement.

Further, it is conceivable that the cornea is applanated in a non-contact manner along the measurement axis, and the applanation is optically detected by the applanation detector. Such an applanation detection unit is hereinafter referred to as an applanation detection optical system. It is preferable that the applanation detection optical system projects an index beam along the measurement axis and obtains an applanation signal based on corneal reflected light from the index beam.

In addition, as an applanation detection optical system, a method of projecting a target light beam from a direction oblique to the measurement axis is known, but a method of projecting the target light beam along the measurement axis as described above is preferable. , a longer alignment tolerance can be secured in the working distance direction, which is advantageous. In addition, the method of projecting the index light flux obliquely requires a space for projecting and receiving the index light flux, so the window formed in the index projector tends to be large. On the other hand, in the method of projecting and receiving the index light flux along the measurement axis, it is easy to reduce the area required for the window.

The device may also be capable of measuring corneal thickness in addition to intraocular pressure. The measured corneal thickness may be used to correct the intraocular pressure measurement. An optical system used for corneal thickness measurement (optical system for corneal thickness measurement) may be provided in the measurement unit. The corneal thickness measurement optical system obliquely projects measurement light onto the cornea. The corneal measurement optical system also has a light receiving element that receives reflected light of the measurement light from each of the anterior surface and the posterior surface of the cornea. The corneal thickness can be obtained based on the signal from the light receiving element. Such a corneal thickness measurement optical system may also be used as an optical system for detecting deformation of the cornea when the intraocular pressure measurement unit measures intraocular pressure by deforming the cornea in a non-contact manner. In this case, the corneal thickness measuring optical system may use slit light as measuring light and pick up a cross-sectional image of the cornea as a slit image.

The apparatus may have an eye refraction measurement unit in addition to the tonometry unit. In this case, the controller can further switch to the eye refractive power measurement mode as the measurement mode of the apparatus. The eye refractive power measurement unit has an eye refractive power measurement optical system. Various configurations are known for eye refractive power measurement optical systems, and any of them can be applied as appropriate.

"Example"
Hereinafter, an ophthalmologic measurement apparatus 1 (hereinafter simply referred to as "apparatus 1") will be described as an embodiment of the present disclosure.

First, with reference to FIGS. 1 to 5, the schematic configuration of the device 1 is shown. Note that FIG. 1 shows the state during eye refractive power and corneal shape measurement, and FIG. 2 shows the state during intraocular pressure measurement.

As shown in FIGS. 1 and 2, the device 1 has at least a measuring section 2 . Additionally, in this embodiment, the device 1 has a base 5 , a face support unit 6 and a carriage 7 .

A face support unit 6 is attached to the base 5 . The face support unit 6 has a chin rest, a forehead rest, and the like. By supporting the subject's face with these members, the position of the subject's eye E is fixed with respect to the apparatus.

In this embodiment, the moving table 7 is provided with a moving mechanism (not shown) for moving on the base 5 in the XZ directions. The moving mechanism may be, for example, a mechanical sliding mechanism.

Further, in the present embodiment, the moving table 7 is provided with an XYZ drive section 7a. The XYZ drive unit 7a moves the measurement unit 2 in each of the X (left and right), Y (up and down), and Z (back and forth) directions with respect to the eye E to be examined. The XYZ driving section 7a may be, for example, a combination of a first driving section for moving in the horizontal (XZ) direction and a second driving section for moving in the vertical (Y) direction. In this embodiment, the XYZ drive section 7a is electrically driven based on a signal from the control section 50 (see FIG. 5).

The measurement section 2 has a placido unit 20 , a first measurement unit 21 and a second measurement unit 22 . The Placido unit 20 is used together with the first measurement unit 21 to measure the corneal shape of the subject's eye. The first measurement unit 21 is used to measure the eye refractive power as the eye characteristic of the eye E to be examined. Also, the second measurement unit 22 is used to measure intraocular pressure as an ocular characteristic of the eye E to be examined.

<Placement of each unit>
1 to 4, the first measurement axis, which is the measurement axis of the first measurement unit 21, is denoted by L1, and the second measurement axis, which is the measurement axis of the second measurement unit 22, is denoted by L2. In this embodiment, the first measurement axis L1 passes through the center of the placido plate 20a and is coaxial with the measurement axis for corneal topography measurement. The second measurement axis L2 passes through a region away from the central portion of the placide plate 20a. Windows 20b and 20c are formed in the placide plate 20a as passage paths for the first measurement axis L1 and the second measurement axis L2 (see FIGS. 3 and 4). The window portion 20b corresponds to the first measurement axis L1, and the first measurement axis L1 passes therethrough. Further, the window portion 20c corresponds to the second measurement axis L2, and the second measurement axis L2 passes therethrough.

In this embodiment, the Placide unit 20 is placed in front of the measurement unit 2 with the front of the Placide plate 20a facing the eye E to be examined. In addition, in this embodiment, the first measurement unit 21 and the second measurement unit 22 are arranged such that the measurement axis L1 of the first measurement unit 21 and the measurement axis L2 of the second measurement unit 22 have different heights. ing. As an example, in this embodiment, the second measurement unit 22 is layered on the first measurement unit 21 .

The measurement unit 2 is moved in the vertical direction (the Y direction shown in FIG. 1) with respect to the subject's eye by an XYZ driving unit 7a provided on the moving table 7. As shown in FIG. In addition, the XYZ drive unit 7a moves the measurement unit 2 in the Y direction with respect to the eye to be inspected, selectively moving one of the first measurement axis L1 and the second measurement axis L2 to the same height as the eye E to be inspected. Driven to match. Therefore, it is necessary to ensure that the XYZ drive unit 7a is driven by at least the distance between the first measurement axis L1 and the second measurement axis L2. More preferably, in each measurement mode, it is preferable to ensure a movable range that allows smooth automatic alignment with respect to the subject's eye.

In this embodiment, the positional relationship between the first measuring unit 21 and the placido unit 20 is fixed.

A second moving section 8 is provided between the first measuring unit 21 and the second measuring unit 22, and the second measuring unit 22 as a whole is driven by the second moving section 8 to move to the first position. It is moved in the front-rear direction with respect to the measurement unit 21 . At this time, the tip (nozzle 22a) of the second measuring unit 22 is moved in the front-rear direction with respect to the surface (front) of the placido unit 20. As shown in FIG. The second drive unit 8 moves the second measurement unit 22 toward the subject's eye E during intraocular pressure measurement, and moves the second measurement unit 22 away from the subject's eye E during corneal shape measurement and refractometer measurement. Used to move away. In this embodiment, during corneal shape measurement and refractometer measurement, the tip of the second measurement unit 22 is retracted until at least the front surface of the placide plate 20a is separated from the subject's eye E. In this embodiment, it is desirable that the distal end of the second measurement unit 22 is retracted from the rear surface of the placido plate 20a during the corneal shape measurement and the refractometer measurement.

<Corneal shape measurement unit>
In this embodiment, the corneal topography measurement unit is formed by the Placide unit 20 and the anterior segment imaging optical system 211 . The corneal topography measuring unit in this embodiment serves both as a topographer and as a keratometer.

The Placido unit 20 is the index projector in this embodiment. The Placido unit 20 projects pattern signatures onto the cornea. In this embodiment, the pattern index is constituted by a ring index with visible light. The placido unit 20 may have at least a light source 201 (referred to as a topo light source, see FIG. 5) suitable for forming pattern indices in addition to the placide plate 20a. A plurality of light sources 201 may be provided, and the light sources 201 may be independent of a part of the ring patterns used for keratometry among the plurality of ring patterns formed on the placido plate 20a and the others. . Since the light sources are independent, in this embodiment, the ring pattern 204 corresponding to the circumferential area with a diameter of 2.4 mm on the cornea can be illuminated independently of the others (see FIG. 3). As shown in FIG. 3, in the placide plate 20a, the ring pattern 204 is formed closer to the central portion of the placide plate 20a than the window portion 20c.

In this embodiment, the pattern index projected from the Placido unit 20 is switchable. During keratometry, one ring index corresponding to a 2.4 mm circumferential area on the cornea is projected from the Placido unit 20 with the cornea placed at the proper working distance on the optical axis L1. .

During topo measurement, a plurality of concentric ring indices are projected onto the cornea placed at an appropriate working distance on the optical axis L1. In this embodiment, a pattern index of a concentric multiple ring pattern is projected from the Placido unit 20 onto an area on the cornea with a diameter of approximately 10 mm or less.

In this embodiment, the surface of the placide plate 20a is flat. Also, the placide plate 20a is formed with a diameter of 200 mm or more. This makes it possible to measure the shape distribution in a range of about 10 mm in diameter on the cornea while ensuring a relatively long working distance.

In addition, in this embodiment, the Placido unit 20 further includes a liquid crystal unit 202 and a liquid crystal moving section 203 . The liquid crystal unit 202 is inserted into and removed from the window portion 20c corresponding to the second measurement axis L2 by the liquid crystal moving portion 203. As shown in FIG. The liquid crystal moving part 203 combines movement in the vertical and horizontal directions and movement in the front-rear direction so that the front surface of the liquid crystal unit 203 and the front surface of the placide plate 20a are arranged substantially on the same plane. By moving 203, the liquid crystal unit 203 may be inserted into the window portion 20c. However, the front face of the liquid crystal unit 203 after being inserted into the window portion 20c and the front face of the placide plate 20a may be displaced in the front-rear direction. Note that the liquid crystal unit 202 is arranged facing the front side toward the subject's eye while being arranged on the window portion 20c.

The front surface of the liquid crystal unit 202 becomes a light emitting surface. As a light source, the liquid crystal unit 202 may be provided with a backlight light source. Also, the topo light source 201 may be used as the light source of the liquid crystal unit 202 .

In this embodiment, since the window portion 20c is formed corresponding to the second measurement axis L2, part of the pattern index (multiple ring index) formed by the placide plate 20a during the topo measurement is not chipped. occurs. The missing part is formed by the liquid crystal unit 202 based on the control signal from the control section 50 . This optically interpolates a portion of the ring index missing due to the window portion 20c.

The liquid crystal unit 202 is inserted at least during corneal shape measurement, and retracted at least during intraocular pressure measurement. After retracting, the nozzle 22a of the second measurement unit 22 is advanced toward the cornea.

In this embodiment, the anterior segment imaging optical system 211 accommodated in the first measurement unit 21 captures the corneal reflected light of the pattern index projected from the placide plate 20a and the liquid crystal unit 202 as a pattern index image. By analyzing the pattern index image, the controller 50 measures the corneal shape. Thus, an optical system used for corneal shape measurement is formed across the platido unit 20 and the first measurement unit 21 .

<Eye refractive power measurement unit>
The first measurement unit 21 is provided with a reflector measurement optical system 212 (see FIG. 5). The optical system 212 includes, for example, a projection optical system that projects a spot-shaped measurement index onto the fundus through the central portion of the pupil of the eye to be examined E, and a ring-shaped projection optical system that projects the fundus reflected light reflected from the fundus through the peripheral portion of the pupil. and a light-receiving optical system for capturing a ring-shaped fundus reflected image with a two-dimensional imaging device (neither is shown).

Also, the first measurement unit 21 may have various optical systems such as the first alignment optical system 213 and the fixation target presentation optical system 214 . Alignment indices from the first alignment optical system 213 are projected onto the cornea, for example, through apertures 213a and 213b formed in the placide plate 20a (see FIGS. 3 and 4).

<Intraocular pressure measurement unit>
A nozzle 22a is provided at the tip of the second measurement unit 22, and a fluid (for example, compressed air) is sprayed onto the cornea of the subject's eye through the nozzle 22a. Then, the intraocular pressure is measured based on the deformation of the cornea due to the fluid spray. The second measurement unit 22 may include, for example, a fluid compression chamber 221 in addition to the nozzle 22a. The fluid compression chamber 221 has a space for compressing the fluid to be sprayed on the cornea, and may be configured by, for example, a cylinder and a piston. The second measurement unit 22 includes various optical systems such as a measurement optical system (applanation detection optical system) 221 for detecting the deformed state of the cornea, an alignment optical system 223, and a fixation target presentation optical system (not shown). may A detection signal from the applanation detection optical system 222 may be input to the control unit 50 and used for intraocular pressure value calculation in the control unit 50 . The second measurement axis L2 may be the optical axis of the applanation detection optical system described above. For further details of the configuration of the second measurement unit 22, see, for example, Japanese Unexamined Patent Application Publication No. 2007-144128 filed by the present applicant. Also, instead of the measurement optical system 221, a pressure sensor may be provided. A pressure sensor detects the pressure in the fluid compression chamber. A detection signal from the pressure sensor may be used by the controller 50 to calculate the intraocular pressure value.

When measuring the intraocular pressure, the tip of the second measurement unit 22 (the tip of the nozzle 22a) needs to be close to the cornea of the eye E to be inspected by about ten and several millimeters. In order to measure the intraocular pressure without bringing the placide plate 20a into contact with the subject's face, in this embodiment, the moving part 8 moves the second measuring unit 22 so that the nozzle 22a protrudes from the front surface of the placide plate 20a. is moved forward.

The alignment index from the second alignment optical system 223 is projected onto the cornea through openings 223a and 223b formed at the tip of the nozzle, for example (see FIG. 4).

For more detailed configurations of the optical systems of the first measurement unit 21 and the second measurement unit 22, see, for example, Japanese Patent Application Laid-Open No. 2016-214466 by the present applicant.

The device 1 may further comprise pachymetry optics 230 . The corneal thickness measurement optical system 230 is used to measure the corneal thickness of the eye E to be examined. For example, projection optics for projecting light for corneal thickness (paki) measurement onto the cornea Ec of the eye to be inspected through an inspection window, which is the tip of the first measurement unit 21, in the housing of the first measurement unit 21. In the lower part of the first measurement unit 21, the light reflected from the cornea of the subject's eye by the above-described light projecting optical system is reflected from below the first measurement axis L1 at different angles to the optical axis (light receiving unit). An imaging (light-receiving) optical system that receives light using the optical axis) may be arranged. Also, the corneal thickness measurement optical system 230 may be provided in the housing of the second measurement unit 22 .

Also, the joystick 71 is part of the UI (user interface) 70 (see FIG. 5) of the device 1 . Also, the joystick 71 is operated by the examiner to change the positional relationship between the eye E to be examined and the measurement unit 2 . In this embodiment, the movable table 7 is horizontally moved on the base 5 by operating the joystick 71 . When the examiner rotates a rotary knob formed on the joystick 71, the measuring section 2 is moved in the Y direction by the XYZ driving section 7a. A measurement start switch may be provided on the top of the joystick 71 .

The monitor 80 displays observation images during alignment, measurement results, and the like. The monitor 80 may be a touch panel display. In this case, monitor 80 may be part of UI 70 .

<Control system>
Next, with reference to FIG. 5, the control system in the device 1 of this embodiment will be described.

The control unit 50 is a processor that controls the entire apparatus and calculates measurement results. The control unit 50 is connected to the XYZ drive unit 7a, the memory 51, the UI 70, the monitor 80, and the like, in addition to each unit of the measurement unit 2. FIG.

The memory 51 may include a rewritable non-transitory storage medium, such as flash memory or hard disk. Images and measurement data obtained as a result of photographing and measurement are stored in the memory 51 . Programs and fixed data defining the measurement operation may be stored in this memory 51 .

<Measurement operation>
The operation of the ophthalmologic measurement apparatus 1 configured as described above will be described. In addition, in the following description, the operation associated with the switching of the measurement mode will be mainly described. For details of the measurement operation for obtaining various eye characteristics, see, for example, Japanese Unexamined Patent Application Publication No. 2007-144128 by the present applicant.

For example, the control unit 50 can select three modes: an eye refractive power measurement mode, an intraocular pressure measurement mode, and a corneal topography measurement mode. Each measurement mode may be switched based on an operation input by the examiner, or may be switched automatically.

In addition, when the intraocular pressure is measured continuously with other ocular characteristics, it is preferable to measure the intraocular pressure after measuring the other ocular characteristics. This is because if the intraocular pressure is measured first, there is a possibility that the effect of spraying fluid or the like will remain. The eye refractive power measurement and the corneal topography measurement may be performed in any order.

In this embodiment, the measurement may be performed in the state shown in FIGS. 1 and 3 between the eye refractive power measurement mode and the corneal topography measurement mode.

That is, the control unit 50 drives the XYZ moving unit 7a to adjust the height of the measuring unit 2, and adjusts the first measurement axis L1 to the height of the eye E to be examined. At this time, the second moving section 8 is driven in advance to retract the tip portion 22a of the second measuring unit 22 from the front surface of the placide plate 20a. This prevents the tip of the nozzle 22a from coming into contact with the subject during height adjustment. Further, the liquid crystal unit 202 may be inserted into the window portion 20c so as to block the space between the tip of the nozzle 22a and the eye E to be examined. Thereby, corneal shape measurement can be performed smoothly at the stage where the alignment adjustment is completed.

Next, alignment of the measurement unit 2 with respect to the subject's eye E in the X, Y, and Z directions is performed. At this time, the control unit 50 may cause the monitor 80 to display a front image of the anterior segment captured by the anterior segment capturing optical system 211 in the first measurement unit 21 as an observation image. Further, the control unit 50 causes the first alignment optical system 213 to project the alignment index. The control unit 50 performs alignment by controlling the XYZ driving unit 7a according to the positional relationship between the alignment index image on the observed image and the anterior segment.

In this embodiment, the Placide plate 20a is formed with a large diameter of 200 mm or more as a target projector, so that it is easy to secure a working distance during corneal topography measurement. Since it is easy to secure the distance, the proper working distance (here, the front surface of the housing between the subject's eye E and the measurement unit 2 in a proper alignment state (here, , the distance to the placide plate 20a) can be easily matched. For example, it can be in the range of about 40 mm to 100 mm. In addition, a relatively long allowable alignment range in the working distance direction can be ensured between the eye refractive power measurement mode and the corneal topography measurement mode. Therefore, in this embodiment, corneal shape measurement and eye refractive power measurement can be performed smoothly and continuously.

After that, when the alignment is completed, eye refractive power measurement and corneal shape measurement are automatically performed.

In addition, in this embodiment, the corneal topography measurement mode is divided into a kerato mode, a topo mode, and a continuous measurement mode. Each measurement mode can be selected in advance by the examiner via the UI 70 . Here, the operation of the device is shown assuming that the continuous measurement mode has been selected.

In the continuous measurement mode, first, the controller 50 performs keratometry. In the keratometric measurement, the pattern 204 (see FIG. 3) of the plurality of ring patterns formed on the placid plate 20a of the controller 50 is selectively caused to emit light. As a result, a ring-shaped pattern index is projected onto a circumferential area with a diameter of 2.4 mm on the cornea. The cornea-reflected light of the pattern index image is captured as an index image by the anterior segment imaging optical system. By analyzing the index image, the control unit 50 obtains the radius of curvature, refraction, strong principal meridian, weak principal meridian, and the like in the above-described circumferential region as measurement results by keratometry.

Next, the control unit 50 determines whether topo measurement is necessary based on the measurement result of the keratometry. In the present embodiment, determination processing is performed by comparing a reliability coefficient, which is a kind of measurement result of keratometry, with a threshold value.

In this embodiment, if the reliability coefficient is greater than the threshold, it may be determined that the topo measurement is unnecessary, and the corneal topography measurement may be terminated. On the other hand, if the confidence factor is less than or equal to the threshold, it is determined that a topo measurement is required. In this case, in the topo measurement, a pattern index is projected by multiple rings from the placide plate 20a and the liquid crystal unit 202. FIG.

It is preferable that the liquid crystal unit 202 is inserted into the window portion 20c in advance during continuous measurement so that the topo measurement can be performed immediately after the keratometry. For example, a keratometry to a topo measurement may be performed in a matter of seconds.

During the topo measurement, the placide plate 20a and the liquid crystal unit 202 may emit light simultaneously or sequentially. As a result, in this embodiment, multiple ring-shaped pattern indices are projected onto a region within a diameter of about 10 mm of the cornea. The cornea-reflected light of the pattern index image is captured as an index image by the anterior segment imaging optical system. The control unit 50 acquires corneal shape distribution data by analyzing the index image.

After completing the corneal topography measurement, the measurement results may be displayed. In this embodiment, at least the measurement results of keratometry (for example, various numerical values) may be displayed. If both keratometry and topometry are measured, both the keratometry and topometry measurements may be displayed simultaneously. In addition, as the first display, together with the measurement result of the keratometry, information indicating that the topo measurement has been performed (that the measurement result of the topo measurement exists) may be displayed. may be displayed as the second display by accepting a display switching operation via the UI 70 while is being performed. In the second display, for example, a corneal shape map based on the distribution data may be output to the monitor 80 or the like as the measurement result. The corneal shape map may be, for example, an elevation map of the cornea, a curvature map, a corneal refractive power map, or the like. At this time, of the corneal shape map, a part of the area interpolated by the light projected from the liquid crystal unit 202 may be displayed in a manner different from the other measurement areas (for example, different colors). However, it is not always necessary to distinguish the display modes.

After completion of eye refractive power measurement or corneal shape measurement, the mode is changed to tonometry mode. At this time, the control unit 50 drives the XYZ drive unit 7a to move the measurement unit 2 downward so that the second measurement axis L2 and the subject's eye E are approximately at the same height (roughly I do not care)
Also, the liquid crystal unit 202 is retracted from the window portion 20c (from the second measurement axis L2). This allows the nozzle 22a to move forward. The control section 50 drives the second drive section 8 to move the second measurement unit 22 in a direction approaching the eye E to be examined. As a result, the nozzle 22a is positioned toward the subject from the front surface of the placido plate 20a. By such an operation, the working distance between the subject's eye E and the apparatus 1 is suitable for intraocular pressure measurement while preventing contact between the front surface of the housing such as the placido plate 20a and the subject's face (for example, nose). adjusted for distance.

When the second measuring unit 22 is moved toward the eye to be inspected, there is a possibility that the tip of the nozzle 22a will come into contact with the eye E to be inspected. 2 is once moved to a rear position in a direction away from the subject's eye E (for example, after being retreated to a reference position set on the most rearward side), the nozzle 22a is protruded by a certain amount from the front surface of the placido plate 20a. may

After that, the control unit 50 performs alignment (for example, Z alignment) when measuring intraocular pressure. The alignment at this time may be performed, for example, based on the corneal reflection image, or may be performed based on other indexes. The index projected onto the subject's eye may be projected from the second alignment optical system 223 of the second measurement unit 22, for example.

After completing the alignment, the controller 50 drives the piston to compress the air in the cylinder, blows the compressed air from the nozzle toward the cornea, and measures the intraocular pressure.

In this embodiment, eye characteristics are measured in each measurement mode as described above.

As described above, the measuring section 2 has the first measuring unit 21 and the second measuring unit 22 stacked on the rear side of the placido unit 20 . When switching between the intraocular pressure measurement mode and other measurement modes, the measurement unit 2 including each unit is moved up and down. Therefore, in the present embodiment, the measurement axes L1 and L2 of each measuring unit do not bypass the placide plate 20a, but are made to pass through the inside of the placide plate 20a by forming windows 20b and 20c in the placide plate 20a. , the first measurement unit 21 and the second measurement unit 22 can be stacked compactly in the vertical direction. Accordingly, the drive range of the XYZ drive unit 7a in the Y direction can be suppressed. As a result, it becomes easier to suppress the size of the entire device. In addition, since the center of gravity of the device 1 can be lowered, it is possible to prevent the measuring section 2 from shifting in the left-right direction when the device 1 moves up and down.

Further, when measuring the corneal topography, the tip of the intraocular pressure measuring unit (nozzle 22a) is arranged at a position retracted from the front surface of the placido plate 20a, so that the pattern index for corneal topography measurement is located at the nozzle 22a. It is well projected onto the cornea without being blocked by

In this case, the lack of the pattern index due to the window portion 20c through which the tip of the tonometry unit enters and exits is interpolated by the partial pattern projection from the liquid crystal unit 202. FIG. Therefore, the corneal shape can be measured satisfactorily.

Although the above has been described based on the embodiments, various modifications are permitted in the above embodiments.

For example, in the above embodiment, the liquid crystal unit 202 is inserted into and removed from the window portion 20c, but this is not necessarily the case. For example, a striped pattern plate 205, which is an example of an interpolation index projector, may be fixedly arranged near the window 20c through which the nozzle 22a passes. For example, a more detailed description is provided with reference to FIGS. 6A-6C. The striped pattern plate 205 may be arranged substantially perpendicular to the front surface of the placide plate 20a. In this case, the light emitting surface of the striped pattern plate 205 is arranged facing the corneal shape measurement axis L1. The light-emitting surface is shielded by a striped mask, thereby projecting a striped pattern. The striped pattern corresponds to the portion of the pattern index from the placid plate 20c that is missing due to the window portion 20c.

Further, among the ends of the window 20c, the striped pattern plate 205 is formed at the end on the measurement axis L1 side, so that it is difficult to block the index light flux from the placide plate 20a. In this case, the amount of protrusion of the striped pattern plate 205 from the front surface of the placid plate 20a should be equal to or less than the amount of protrusion of the nozzle 22a during intraocular pressure measurement. It is preferable to do so. The striped pattern plate 205 may be formed integrally with the placide plate 20a, or may use the topo light source 201 as a light source. Also, instead of the striped pattern plate 205, a liquid crystal unit as in the above embodiment may be fixedly arranged.

Also, the striped pattern plate 205 (an example of an interpolation index projector) may be movable in the front-rear direction. In this case, the apparatus 1 may have a moving part for moving the striped pattern plate 205 in the front-rear direction. The moving section may be used in common with the second driving section 8 (the moving section of the second measurement unit 22), or may be a separate body.

The striped pattern plate 205 is positioned forward of the front surface of the placido plate 20a at least in the corneal topography measurement mode. On the other hand, in the eye refractive power measurement mode and the intraocular pressure measurement mode, the striped pattern plate 205 may be retracted more than during measurement in the corneal topography measurement mode. Furthermore, when switching between the corneal topography measurement mode or the eye refractive power measurement mode and the intraocular pressure measurement mode (particularly during the vertical movement of the measurement unit 2), the striped pattern plate 205 is retracted. is preferred. It becomes difficult for the striped pattern plate 205 to come into contact with the subject's face.

Furthermore, the striped pattern plate 205 (an example of an interpolating index projector) that moves in the front-rear direction may be formed on the side surface (lower surface in this embodiment) of the nozzle of the intraocular pressure measurement unit 22 .

For example, in the above embodiment, the pattern index is projected also in the keratomode from the index projector capable of projecting the pattern index for obtaining the corneal shape distribution information. However, it is not necessarily limited to this, and in the keratomode, curvature information in a single circumferential region may be obtained by projecting a pattern index onto the cornea from an optical system other than the index projector. In this case, the ophthalmologic measuring device may have a keratofiducial projection optical system independent of the fiducial projector. The measurement axis of the kerato-index projection optics is preferably coaxial with the measurement axis used for pattern index-based corneal topography measurement from the index projector. However, it is not necessarily limited to this.

Further, for example, in the above-described embodiment, the case where the first measurement unit 21 and the second measurement unit 22 are stacked has been described. may be arranged side by side in one radial direction, or may be arranged side by side in the horizontal direction.

1 ophthalmologic measuring apparatus 20 placide unit 20a placide plates 20b, 20c window portion 21 first measurement unit 22 second measurement unit E eye to be examined L1 measurement axis L2 measurement axis

Claims (1)

an intraocular pressure measurement unit having a distal end and measuring the intraocular pressure of the subject's eye with the distal end approaching the cornea of the subject's eye;
a plate-like index projector having a window for exposing the tip portion to the side of the eye to be examined, and projecting a pattern index for measuring the shape of the cornea onto the cornea of the eye to be examined;
a moving unit that moves at least the distal end portion of the intraocular pressure measurement unit in the front-rear direction relative to the index projector;
a control unit for switching a measurement mode between a corneal topography measurement mode for measuring corneal topography and an intraocular pressure measurement mode for measuring intraocular pressure;
The control section controls the moving section in accordance with the measurement mode so that the distal end portion of the intraocular pressure measurement unit moves to the first position on the subject's eye side with respect to the surface of the index projector in the intraocular pressure measurement mode. 1 position and, in the corneal topography measurement mode, in a second position retracted with respect to the first position.

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