JP2021069539A - Ophthalmologic information processing device, ophthalmologic device, ophthalmologic information processing method, and program - Google Patents

Abstract

To provide a new technology to acquire information indicating a cornea shape in a wide range of the cornea of an eye to be examined by a simple configuration.SOLUTION: An ophthalmologic information processing device includes an acquisition unit and an estimation unit. The acquisition unit acquires two or more pieces of cornea shape information at two or more positions on the cornea of the eye to be examined. The estimation unit estimates cornea shape information at an extrapolation position on a straight line passing through two or more positions on the basis of the two or more pieces of cornea shape information.SELECTED DRAWING: Figure 6

Description

The present invention relates to an ophthalmic information processing device, an ophthalmic device, an ophthalmic information processing method, and a program.

Information representing the shape of the cornea (surface) of the eye to be inspected is useful for diagnosing corneal diseases and selecting the optimum contact lens. Information representing the shape of such a cornea is acquired by using a corneal shape measuring device.

The corneal shape measuring device projects a ring pattern on the cornea of the eye to be inspected and acquires information representing the corneal shape from the reflected image obtained by detecting the return light (for example, Patent Document 1 and Patent Document 2). ).

Further, there is known an optical characteristic measuring device provided with a Hartmann plate and capable of calculating corneal aberration (for example, Patent Document 3). This optical characteristic measuring device can calculate the Zernike coefficient based on the amount of displacement due to the distortion of the platidling image, and can calculate the corneal aberration using the calculated Zernike coefficient.

Japanese Unexamined Patent Publication No. 2003-102686 JP-A-2007-061313 JP-A-2002-204784

However, when acquiring information representing the shape of the cornea over a wide range of the cornea, it is necessary to shift the line of sight of the eye to be inspected or the configuration becomes complicated in the conventional method.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide a new technique for obtaining information representing a corneal shape in a wide range of the cornea of an eye to be inspected with a simple configuration. It is in.

The first aspect of the embodiment passes through the two or more positions based on the acquisition unit that acquires the two or more corneal shape information at the two or more positions on the cornea of the eye to be inspected and the two or more corneal shape information. It is an ophthalmic information processing device including an estimation unit that estimates corneal shape information at an external position on a straight line.

In the second aspect of the embodiment, in the first aspect, the estimation unit extrapolates based on a function representing an aspherical surface approximated to a shape corresponding to the two or more corneal shape information at the two or more positions. Obtain corneal shape information at the position.

In the third aspect of the embodiment, in the second aspect, the function representing the aspherical surface is a function representing a conic surface.

In the fourth aspect of the embodiment, in any one of the first to third aspects, the two or more positions are positions on two or more concentric ring pattern images centered on the reference position on the straight line. is there.

In the fifth aspect of the embodiment, in the fourth aspect, the acquisition unit acquires two or more corneal shape information at two or more positions on the meridian for each of the two or more meridian lines passing through the reference position. The estimation unit estimates the corneal shape information at the extrapolation position on the meridian passing through the two or more positions for each of the two or more meridian lines, and is approximated based on the estimated two or more corneal shape information. The corneal shape information at a predetermined position on a predetermined meridian line different from the two or more meridian lines is obtained from the function.

In the sixth aspect of the embodiment, in the fifth aspect, the predetermined function is a trigonometric function.

In the seventh aspect of the embodiment, in any of the fourth to sixth aspects, the extrapolation position is a position opposite to the reference position side with respect to the two or more positions.

In the eighth aspect of the embodiment, in any of the fourth to sixth aspects, the extrapolation position is a position on the reference position side with respect to the two or more positions.

A ninth aspect of the embodiment is centered on an objective lens, an optical power measuring optical system that projects light onto the eye to be inspected through the objective lens and detects return light from the eye to be inspected, and a reference position. The corneal shape measurement optical system that projects the two or more ring patterns to be examined onto the corneum of the eye to be inspected and detects the return light from the corneum, and the subject based on the return light detected by the refractive power measurement optical system. An optical power calculation unit that calculates the refractive power of the optometry, and a corneal shape information calculation unit that calculates two or more corneal shape information at the two or more positions based on the return light detected by the corneal shape measurement optical system. And the optometry apparatus including the seventh aspect of the optometry information processing apparatus.

A tenth aspect of the embodiment has an objective lens and an optical scanner, the light from the light source is deflected by the optical scanner, and the light deflected by the optical scanner is projected onto the eye to be inspected through the objective lens. Then, an inspection optical system that detects the return light from the eye to be inspected, and a corneal shape that projects two or more ring patterns centered on the reference position onto the cornea of the eye to be inspected and detects the return light from the corneum. The measurement optical system, the corneal shape information calculation unit that calculates two or more corneal shape information at the two or more positions based on the return light detected by the corneal shape measurement optical system, and the ophthalmic information processing of the eighth aspect. A device and an ophthalmic device including.

The eleventh aspect of the embodiment passes through the two or more positions based on the acquisition step of acquiring the two or more corneal shape information at the two or more positions on the cornea of the eye to be inspected and the two or more corneal shape information. It is an ophthalmic information processing method including an estimation step for estimating corneal shape information at an extrapolation position on a straight line.

In the twelfth aspect of the embodiment, in the eleventh aspect, the estimation step is extrapolated based on a function representing an aspherical surface approximated to a shape corresponding to the two or more corneal shape information at the two or more positions. Obtain corneal shape information at the position.

In the thirteenth aspect of the embodiment, in the twelfth aspect, the function representing the aspherical surface is a function representing a conic surface.

In the 14th aspect of the embodiment, in any of the 11th to 13th aspects, the two or more positions are positions on the two or more concentric ring pattern images centered on the reference position on the straight line. is there.

In the fifteenth aspect of the embodiment, in the fourteenth aspect, the acquisition step acquires two or more corneal shape information at two or more positions on the meridian for each of the two or more meridian lines passing through the reference position. The estimation step estimates the corneal shape information at the extrapolation position on the meridian passing through the two or more positions for each of the two or more meridian lines, and is approximated based on the estimated two or more corneal shape information. The corneal shape information at a predetermined position on a meridian different from the two or more meridians is obtained from the function.

In the 16th aspect of the embodiment, in the 15th aspect, the predetermined function is a trigonometric function.

In the 17th aspect of the embodiment, in any of the 14th to 16th aspects, the extrapolation position is a position opposite to the reference position side with respect to the two or more positions.

In the eighteenth aspect of the embodiment, in any of the fourteenth to sixteenth aspects, the extrapolation position is a position on the reference position side with respect to the two or more positions.

A nineteenth aspect of the embodiment is a program that causes a computer to execute each step of the ophthalmic information processing method according to any one of the eleventh to eighteenth aspects.

In addition, it is possible to arbitrarily combine the configurations according to the above-mentioned plurality of aspects.

According to the present invention, it is possible to obtain information representing the corneal shape in a wide range of the cornea of the eye to be inspected with a simple configuration.

It is the schematic which shows the appearance structure of the ophthalmic apparatus which concerns on 1st Embodiment. It is the schematic which shows the structural example of the ophthalmic apparatus which concerns on 1st Embodiment. It is the schematic which shows the structural example of the optical system of the ophthalmic apparatus which concerns on 1st Embodiment. It is a schematic diagram which shows the structural example of the control system of the ophthalmic apparatus which concerns on 1st Embodiment. It is a schematic diagram which shows the structural example of the control system of the ophthalmic apparatus which concerns on 1st Embodiment. It is a schematic diagram which shows the structural example of the control system of the ophthalmic apparatus which concerns on 1st Embodiment. It is operation explanatory drawing of the ophthalmic apparatus which concerns on 1st Embodiment. It is operation explanatory drawing of the ophthalmic apparatus which concerns on 1st Embodiment. It is operation explanatory drawing of the ophthalmic apparatus which concerns on 1st Embodiment. It is operation explanatory drawing of the ophthalmic apparatus which concerns on 1st Embodiment. It is operation explanatory drawing of the ophthalmic apparatus which concerns on 1st Embodiment. It is a flow chart of the operation example of the ophthalmic apparatus which concerns on 1st Embodiment. It is a flow chart of the operation example of the ophthalmic apparatus which concerns on 1st Embodiment. It is a flow chart of the operation example of the ophthalmic apparatus which concerns on 1st Embodiment. It is operation explanatory drawing of the ophthalmic apparatus which concerns on the modification of 1st Embodiment. It is operation explanatory drawing of the ophthalmic apparatus which concerns on the modification of 1st Embodiment. It is operation explanatory drawing of the ophthalmic apparatus which concerns on the modification of 1st Embodiment. It is the schematic which shows the structural example of the optical system of the ophthalmic apparatus which concerns on 2nd Embodiment. It is the schematic which shows the structural example of the optical system of the ophthalmic apparatus which concerns on 2nd Embodiment. It is operation explanatory drawing of the ophthalmic apparatus which concerns on 2nd Embodiment. It is operation explanatory drawing of the ophthalmic apparatus which concerns on 2nd Embodiment. It is a schematic diagram which shows the structural example of the control system of the ophthalmic apparatus which concerns on 2nd Embodiment. It is operation explanatory drawing of the ophthalmic apparatus which concerns on 2nd Embodiment. It is operation explanatory drawing of the ophthalmic apparatus which concerns on 2nd Embodiment.

An example of an ophthalmic information processing apparatus, an ophthalmic apparatus, an ophthalmic information processing method, and an embodiment of a program according to the present invention will be described in detail with reference to the drawings. It should be noted that the description contents of the documents cited in this specification and arbitrary known techniques can be incorporated into the following embodiments.

The ophthalmic information processing apparatus according to the embodiment acquires two or more corneal shape information at two or more positions on the cornea (surface) of the eye to be inspected, and based on the acquired two or more corneal shape information, the above 2 It is possible to estimate the corneal shape information at the extrapolation position on the straight line passing through the above positions. The corneal shape information is information representing the shape of the cornea. Examples of corneal shape information include the radius of curvature of the cornea, the curvature of the cornea, and the refractive power of the cornea. When 3 or more corneal shape information at 3 or more positions is acquired, the straight line passing through the 3 or more positions may be an approximate straight line of the 3 or more positions. The approximate straight line is obtained by applying a known method such as the least squares method to 3 or more positions.

For example, corneal shape information is obtained using a known ophthalmic apparatus. In this case, the ophthalmologic apparatus projects two or more concentric ring patterns (for example, a keratling pattern or a platiding pattern) onto the cornea of the eye to be inspected and receives the return light. The ophthalmic apparatus analyzes two or more ring pattern images obtained by receiving the return light, and acquires corneal shape information at a position on each ring pattern image. The corneal shape information at the extrapolation position on a straight line (or an approximate straight line; the same applies hereinafter) passing through the acquisition position of the corneal shape information is estimated by extrapolating the corneal shape information at the acquisition position. In some embodiments, the straight line passes through a reference position on the cornea. Examples of the reference position include the center position of the cornea, the position of the center of gravity of the cornea, the position of the apex of the cornea, and the position (alignment reference position) that serves as a reference for the alignment of the device optical system with respect to the eye to be inspected, which will be described later. In some embodiments, the two or more ring patterns described above are concentric patterns centered on the reference position of the cornea.

In some embodiments, the extrapolation position is a position opposite to the reference position side with respect to the above two or more positions. In this case, when projecting a ring pattern having a small diameter centered on the reference position, it is possible to estimate the corneal shape information outside the ring pattern. As a result, it becomes possible to acquire corneal shape information in a wider range of the cornea with a small number of ring patterns.

In some embodiments, the extrapolation position is a position on the reference position side with respect to the above two or more positions. In this case, when projecting a ring pattern having a large diameter centered on the reference position, it is possible to estimate the corneal shape information inside the ring pattern. As a result, it becomes possible to acquire corneal shape information in a wider range of the cornea with a small number of ring patterns.

Further, in some embodiments, the corneal shape information at the extrapolation position is estimated based on the acquired two or more corneal shape information for each of the two or more meridians passing through the reference position. By obtaining the corneal shape information at a predetermined position on a meridian different from the above two or more meridians from a predetermined function approximated based on two or more corneal shape information at two or more extrapolated positions, astigmatism occurs. It is possible to identify the corresponding corneal shape information.

The ophthalmic information processing method according to the embodiment includes one or more steps for realizing a process executed by a processor (processing circuit, computer) in the ophthalmic information processing apparatus according to the embodiment. The program according to the embodiment causes a processor to execute each step of the ophthalmic information processing method according to the embodiment.

In the present specification, the "processor" is, for example, a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), an ASIC (Application Specific Integrated Circuit), a programmable logic device (for example, a SPLD (Simple Program) It means a circuit such as Programmable Logical Device) and FPGA (Field Programmable Gate Array). The processor realizes the function according to the embodiment by reading and executing a program stored in a storage circuit or a storage device, for example.

Hereinafter, a case where the ophthalmic apparatus according to the embodiment has a function of the ophthalmic information processing apparatus according to the embodiment will be described. However, the ophthalmic information processing apparatus according to the embodiment may be configured to acquire corneal shape information from an external ophthalmic apparatus. Further, even if the ophthalmic information processing apparatus according to the embodiment is configured to acquire the light receiving results of two or more ring patterns projected on the cornea and calculate the corneal shape information based on the acquired light receiving results. Good.

Hereinafter, for convenience of explanation, a case where two concentric ring patterns (kerat ring patterns) centered on the center position of the cornea are projected onto the cornea will be mainly described in the corneal shape measurement.

<First Embodiment>
The ophthalmic apparatus according to the first embodiment projects a small-diameter ring pattern onto the cornea in order to measure the shape of the cornea under the constraints caused by the type of examination (measurement) and the arrangement of the optical system. In this case, the corneal shape information at the extrapolated position outside the projected position of the ring pattern on the cornea is estimated.

Hereinafter, a case where the ophthalmic apparatus according to the embodiment is an ophthalmologic examination apparatus capable of subjective examination and objective measurement for both the left eye and the right eye to be examined will be described. However, the ophthalmologic examination apparatus according to the embodiment may be capable of subjective examination and objective measurement for only one of the left eye and the right eye.

[Constitution]
FIG. 1 schematically shows an outline of the appearance configuration of the ophthalmologic examination apparatus according to the embodiment. The ophthalmic examination device 1 according to the embodiment is an ophthalmic examination device capable of performing subjective examination and objective measurement. The subjective test is a test for presenting an optotype to the eye of a subject (the eye to be inspected) and acquiring information on the eye to be inspected based on a response from the subject regarding the appearance of the optotype. Objective measurement is a measurement for acquiring information about an eye to be examined mainly by using a physical method without referring to a response from the subject.

The ophthalmologic examination device 1 can be connected to a controller for an examiner (for example, a tablet terminal) or a controller for an examinee (for example, a control lever unit) (not shown) via a wired or wireless communication path. The ophthalmologic examination device 1 is controlled based on an operation on the controller for the examiner or the controller for the subject. In the following, the left-right direction as seen from the subject may be the X direction, the vertical direction may be the Y direction, and the depth direction of the measurement head 100 as seen from the subject may be described as the Z direction.

The ophthalmologic examination device 1 includes a measurement head 100 and a control device 200. The measuring head 100 is provided with an optical system and a moving mechanism system for performing the above-mentioned subjective examination and objective measurement. The control device 200 controls the measurement head 100 and the controller for the examiner or the controller for the subject.

The ophthalmologic examination device 1 includes an eye examination table 3. The optometry table 3 is a desk for supporting the measurement head 100 and placing the controller for the examiner or the controller for the subject. The optometry table 3 is installed while being supported on the floor by the support portion 4. The height of the optometry table 3 can be adjusted in the vertical direction.

A support column 5 is erected on the optometry table 3. The base end portion of the lateral arm 6 is held at the tip end portion of the support column 5. A measurement head 100 is suspended from the tip of the lateral arm 6. For example, the support column 5 can be rotated in the axial direction (arrow direction j, arrow direction k) by the arm moving mechanism 7. As a result, the lateral arm 6 is rotated in the axial direction. That is, the measurement head 100 is rotated in the axial direction. Therefore, the measurement head 100 can be retracted from the examination space above the optometry table 3, and the examination can be efficiently performed by utilizing the empty space on the optometry table 3.

The arm moving mechanism 7 may move the tip end portion of the support column 5 in the vertical direction (arrow direction h) as the arm vertical movement mechanism. As a result, the lateral arm 6 is moved in the vertical direction. That is, the measurement head 100 is moved in the vertical direction. The arm moving mechanism 7 may move the lateral arm 6 in the vertical direction by expanding and contracting the support column 5 protruding upward from the optometry table 3 as an arm expanding / contracting mechanism. Even in this case, the measurement head 100 can be moved up and down according to the sitting height of the subject, and the measurement head 100 can be retracted from the examination space above the optometry table 3.

A stand for storing the measuring head 100 may be separately provided, and the measuring head 100 may be arranged at a stable position by the above-mentioned rotation or vertical movement. In this case, it is possible to continuously reduce the load on the lateral arm 6 due to the weight of the measuring head 100.

The arm moving mechanism 7 can manually move the lateral arm 6 in the axial direction or the vertical direction in response to an operation by the operator. The arm moving mechanism 7 may move the lateral arm 6 by an electric mechanism. In this case, an actuator for generating a driving force for moving the arm moving mechanism 7 and a transmission mechanism for transmitting the driving force are provided. The actuator is composed of, for example, a pulse motor. The transmission mechanism is composed of, for example, a combination of gears and a rack and pinion.

A storage unit 9 is provided on the side surface of the support unit 4, and the control device 200 is stored. The configuration of the optometry table 3 is not limited to the configuration shown in FIG.

[Measurement head]
The measuring head 100 includes a left eye inspection unit 120L and a right eye inspection unit 120R. The left eye examination unit 120L and the right eye examination unit 120R are formed with optometry windows 130L and 130R, respectively. The left eye of the subject (the left eye to be examined) is examined through the optometry window 130L. The subject's right eye (right eye) is examined through the optometry window 130R.

FIG. 2 shows a block diagram of a configuration example of the measurement head 100 according to the embodiment. The measuring head 100 includes a moving mechanism system 110, a left eye inspection unit 120L, and a right eye inspection unit 120R. The moving mechanism system 110 is suspended from the lateral arm 6. The left eye inspection unit 120L and the right eye inspection unit 120R are three-dimensionally moved by the moving mechanism system 110 independently or in conjunction with each other. The left eye examination unit 120L accommodates an optical system for examination of the left eye to be inspected. The right eye examination unit 120R houses an optical system for examination of the right eye to be inspected.

(Movement mechanism system)
The moving mechanism system 110 includes a horizontal moving mechanism 111, rotating mechanisms 112L and 112R, and vertical moving mechanisms 113L and 113R. The moving mechanism system 110 may further include an arm moving mechanism 7.

The horizontal movement mechanism 111 is a horizontal movement mechanism 112L, 112R, a vertical movement mechanism 113L, 113R, a left eye inspection unit 120L, and a right eye inspection unit 120R in the horizontal direction (horizontal direction (X direction), front-back direction (Z direction)). ). Thereby, the horizontal positions of the eye examination windows 130L and 130R can be adjusted according to the arrangement position of the eye to be inspected. The horizontal movement mechanism 111 has, for example, a known configuration using a pulse motor, a feed screw, or the like, and receives a control signal from the control device 200 to move the rotation mechanisms 112L, 112R, and the like in the horizontal direction. The horizontal movement mechanism 111 can also be operated by an operator to manually move the above-mentioned rotation mechanisms 112L, 112R, etc. in the horizontal direction.

The rotation mechanism 112L rotates the vertical movement mechanism 113L and the left eye inspection unit 120L around a predetermined first axis connected to the horizontal movement mechanism 111. The first axis is an axis extending in a substantially vertical direction, and may be inclined at an arbitrary angle with respect to a horizontal plane. The rotating mechanism 112L has, for example, a known configuration using a pulse motor, a rotating shaft, or the like, and rotates the left eye inspection unit 120L or the like around the first axis in response to a control signal from the control device 200. Let me. The rotation mechanism 112L can also manually rotate the left eye inspection unit 120L or the like around the first axis in response to an operation by the operator.

The rotation mechanism 112R rotates the vertical movement mechanism 113R and the inspection unit 120R for the right eye around a predetermined second axis connected to the horizontal movement mechanism 111. The second axis is an axis extending in a substantially vertical direction like the first axis, and may be inclined at an arbitrary angle with respect to the horizontal plane. The second axis is an axis arranged at a position separated from the first axis by a predetermined distance. The distance between the first axis and the second axis is adjustable. The rotation mechanism 112R may rotate the right eye inspection unit 120R or the like in conjunction with the rotation of the rotation mechanism 112L, or the right eye inspection unit 120R independently of the rotation of the rotation mechanism 112L. Etc. may be rotated. The rotation mechanism 112R has a known configuration similar to that of the rotation mechanism 112L, and receives a control signal from the control device 200 to rotate the inspection unit 120R for the right eye or the like around the second axis. The rotation mechanism 112R can also manually rotate the right eye inspection unit 120R or the like around the second axis in response to an operation by the operator.

By rotating the left eye inspection unit 120L and the right eye inspection unit 120R by the rotating mechanisms 112L and 112R, the orientations of the left eye inspection unit 120L and the right eye inspection unit 120R are relatively changed. Is possible. For example, the left eye examination unit 120L and the right eye examination unit 120R are rotated in opposite directions around the eye rotation points of the left and right eyes of the subject. As a result, the eye to be inspected can be dissected and congested.

The vertical movement mechanism 113L moves the left eye inspection unit 120L in the vertical direction (Y direction). Thereby, the position of the optometry window 130L in the height direction can be adjusted according to the arrangement position of the optometry subject. The vertical movement mechanism 113L has, for example, a known configuration using a pulse motor, a feed screw, or the like, and receives a control signal from the control device 200 to move the left eye inspection unit 120L in the vertical direction. The vertical movement mechanism 113L can also be operated by an operator to manually move the left eye inspection unit 120L in the vertical direction.

The vertical movement mechanism 113R moves the inspection unit 120R for the right eye in the vertical direction. Thereby, the position of the optometry window 130L in the height direction can be adjusted according to the arrangement position of the optometry subject. The vertical movement mechanism 113R may move the right eye inspection unit 120R in conjunction with the movement by the vertical movement mechanism 113L, or the right eye inspection unit 120R may be moved independently of the movement by the vertical movement mechanism 113L. May be good. The vertical movement mechanism 113R has a known configuration similar to that of the vertical movement mechanism 113L, and receives a control signal from the control device 200 to move the inspection unit 120R for the right eye in the vertical direction. The vertical movement mechanism 113R can also be operated by an operator to manually move the inspection unit 120R for the right eye in the vertical direction.

(Configuration of each inspection unit)
The left eye examination unit 120L and the right eye examination unit 120R can operate individually.

The left eye examination unit 120L includes a first visual target display unit 122L, a first objective measurement unit 123L, and a first imaging unit 124L. The first optotype presenting unit 122L selectively presents a plurality of optotypes to the left eye to be inspected. The first objective measurement unit 123L is used to measure the objective refraction of the left eye to be inspected. The first imaging unit 124L photographs the anterior segment of the left eye to be inspected. The left eye inspection unit 120L may be provided with an optical element application unit that selectively applies a plurality of optical elements that can be arranged between the left eye to be inspected and the deflection member PL described later to the left eye to be inspected. ..

The right eye examination unit 120R includes a second visual target display unit 122R, a second objective measurement unit 123R, and a second imaging unit 124R. The second optotype presenting unit 122R selectively presents a plurality of optotypes to the right eye to be inspected. The second objective measurement unit 123R is used to measure the objective refraction of the right eye to be inspected. The second imaging unit 124R photographs the anterior segment of the right eye to be inspected. The right eye inspection unit 120R may be provided with an optical element application unit that selectively applies a plurality of optical elements that can be arranged between the right eye to be inspected and the deflection member PR described later to the right eye to be inspected. ..

The left eye inspection unit 120L and the right eye inspection unit 120R include an optical system as shown in FIG. By operating the optical system of the left eye inspection unit 120L and the right eye inspection unit 120R, the left eye examination EL and the right eye examination unit ER can be subjected to subjective examination using the optotype display unit and others. It is configured to perform objective refraction measurement using the optometry unit and the imaging unit. The examiner and the examinee perform the inspection by appropriately operating the controller and the like.

When each inspection unit is provided with the above-mentioned optical element application unit, the optical element application unit includes a plurality of optical elements and a drive mechanism. The plurality of optical elements are a set of various lenses for inspecting the visual function of the eye to be inspected, and include, for example, at least one of a spherical lens, a cylindrical lens, and a prism lens. The plurality of optical elements are grouped according to the type of optometry parameter. For example, the type of optometry parameter includes at least one of spherical power, astigmatic power, astigmatic axis angle, addition power, interpupillary distance, prism power, and prism base direction. As a grouping for each type of optometry parameters, a set of spherical powers includes a plurality of spherical lenses, each of which is composed of spherical lenses having different spherical powers. The astigmatic power set includes a plurality of cylindrical lenses, each of which is composed of cylindrical lenses having different astigmatic powers. The astigmatic power set may be further rotatable according to the astigmatic axis angle. The addition power set is composed of a removable positive power spherical lens and a negative power spherical lens. A set of prism powers includes a plurality of prism lenses, each of which is composed of prism lenses having different prism powers. The set of prism powers may be further rotatable in the direction of the prism base. The interpupillary distance is an examination condition set according to the interpupillary distance of the eye to be inspected. The interpupillary distance is set by sliding one or both of the left eye inspection unit 120L and the right eye inspection unit 120R in the horizontal direction (arrow direction m in FIG. 1).

The drive mechanism included in each inspection unit is configured so that each of the plurality of optical elements can be arranged in the optometry window and retracted from the optometry window. Each drive mechanism receives a control signal from the control device 200 and switches the optical element. Thereby, at least one of spherical power, astigmatism power, astigmatism axis angle, addition power, interpupillary distance, prism power, and prism base direction can be switched and applied to the eye to be inspected.

[Optical system configuration]
FIG. 3 shows a configuration example of the optical system housed in the measurement head 100. FIG. 3 shows a block diagram of a configuration example of an optical system housed in the left eye inspection unit 120L and the right eye inspection unit 120R.

The left eye inspection unit 120L includes a deflection member PL, an optotype display optical system 10L, a photographing optical system 20L, an alignment optical system 30L and 31L, a reflex measurement optical system 40L, and a kerato measurement optical system 50L. .. The left eye inspection unit 120L is provided with an objective lens 60L and beam splitters BS1L to BS3L. The inspection unit 120R for the right eye includes a deflection member PR, an optotype display optical system 10R, a photographing optical system 20R, an alignment optical system 30R and 31R, a reflex measurement optical system 40R, and a kerato measurement optical system 50R. .. The right eye inspection unit 120R is provided with an objective lens 60R and beam splitters BS1R to BS3R. The optical system of the left eye inspection unit 120L and the optical system of the right eye inspection unit 120R are symmetrically configured. Hereinafter, unless otherwise specified, the optical system of the left eye examination unit 120L will be described.

The optotype presenting optical system 10L is an optical system for projecting an optotype on the fundus Ef of the left eye subject EL. The optotype display optical system 10L includes an LCD (Liquid Crystal Display) 11L, a moving lens 70L, and a reflection mirror ML. The LCD 11L displays various optotypes (charts) for optometry. On the LCD11L, a fixation target composed of a landscape chart, a visual acuity chart such as a Randold ring for visual acuity test, a cross cylinder test chart, a radiation chart for astigmatism test, a cross chart for oblique position test, a red-green test chart, etc. The markers are displayed selectively. In the optotype display optical system 10L, instead of the LCD 11L, an electronic display device using EL (electroluminescence) or the like, or any of a plurality of optotypes drawn on a rotating glass plate or the like is appropriately placed on the optical axis. What is arranged (turret type) may be provided.

The moving lens 70L is movable in the optical axis direction of the optotype display optical system 10L. The moving lens 70L is moved by the drive mechanism 70DL (described later). The drive mechanism 70DL moves the moving lens 70L in response to a control signal from the control device 200. Thereby, it is possible to change the sphericality added to the left eye subject EL. For example, by moving the moving lens 70L in the optical axis direction by the amount of movement corresponding to the refractive power of the left eye subject EL at the time of reflex measurement, it is possible to perform fixation cloud fog on the left eye subject EL. In addition, at the time of subjective examination, the optotype can be presented at a position corresponding to the far point of the eye to be inspected, a position corresponding to the near point, or an arbitrary position in between, and the examination can be performed at an arbitrary examination distance. it can.

The light from the LCD 11L passes through the moving lens 70L and is reflected by the reflection mirror ML. The light reflected by the reflection mirror ML passes through the beam splitter BS2L and is reflected by the beam splitter BS1L. The light reflected by the beam splitter BS1L passes through the objective lens 60L and is deflected toward the fundus Ef of the left eye subject EL by the deflection member PL.

The optotype presentation optical system 10L may be provided with a VCS lens for correcting the astigmatic power and the astigmatic axis angle of the left eye subject EL.

The photographing optical system 20L is an optical system for photographing the anterior segment of the left eye subject EL. The photographing optical system 20L includes a CCD (Charged-Coupled Device) 21L. For example, when the anterior segment of the left eye subject EL is illuminated by an anterior segment illumination system (not shown), the reflected light from the anterior segment of the left eye subject EL is incident on the deflection member PL. The deflection member PL deflects the reflected light toward the objective lens 60L. The reflected light deflected by the deflection member PL passes through the objective lens 60L, passes through the beam splitters BS1L and BS3L, and is imaged on the light receiving surface of the CCD 21L by a CCD lens or the like (not shown). Further, the photographing optical system 20L functions as a light receiving system that receives the reflected light of the measured luminous flux projected on the left eye subject EL in the reflex measurement and the kerato measurement.

The alignment optical system 30L is an optical system for aligning the optical system of the left eye inspection unit 120L with respect to the left eye EL to be aligned in the XY directions. The alignment optical system 30L projects a luminous flux (parallel light) for alignment onto the left eye EL to be inspected. The luminous flux for alignment is reflected by the beam splitter BS3L, passes through the beam splitter BS1L, passes through the objective lens 60L to be a substantially parallel luminous flux, and is deflected toward the cornea of the left eye subject EL by the deflection member PL. The light reflected by the cornea of the luminous flux for alignment projected on the left eye EL is returned by the same path as the incident path, passes through the beam splitter BS3L, and is received by the CCD21L of the photographing optical system 20L.

The alignment optical system 31L is an optical system for aligning the optical system of the left eye inspection unit 120L with respect to the left eye EL to be aligned in the Z direction (or XYZ direction). The alignment optical system 31L includes two or more photographing optical systems that photograph the anterior segment of the left eye EL to be photographed substantially simultaneously from two or more directions different from each other. Hereinafter, the alignment optical system 31L assumes that the left eye subject EL is photographed from two different directions by the two photographing optical systems. Each photographing optical system includes an infrared camera including a CCD having high sensitivity in the near-infrared region as a narrow-range camera and an imaging lens for forming an image of light from the left eye EL to be formed on the light receiving surface of the CCD. .. Each imaging optical system can photograph not only the anterior segment of the eye to be inspected (pupil or iris) but also at least a part of the upper eyelid and at least a part of the lower eyelid of the eye to be inspected. Alignment in the Z direction (working distance direction) is performed from the parallax obtained based on the captured images of the anterior segment from two or more different directions acquired by using these photographing optical systems.

The reflex measurement optical system 40L is an optical system for performing reflex measurement (objective refraction measurement, eye refraction force measurement) of the left eye subject EL. The luminous flux for reflex measurement emitted by the reflex measurement optical system 40L is reflected by the beam splitter BS2L, reflected by the beam splitter BS1L, passes through the objective lens 60L, and is directed to the fundus Ef of the left eye subject EL by the deflection member PL. Is biased. The reflected light from the fundus of the light beam for reflex measurement projected on the left eye EL is returned by the same path as the incident path, passes through the beam splitters BS1L and BS3L, and is received by the CCD21L of the photographing optical system 20L.

The kerato measurement optical system 50L is an optical system for performing kerato measurement of the left eye subject EL. For example, the kerato measurement optical system 50L includes a kerat ring light source and a kerato plate on which a translucent portion corresponding to two ring patterns is formed. When the light from the kerat ring light source illuminates the kerato plate, the light transmitted through the translucent portion forms two ring patterns. The two ring patterns formed are deflected by the deflection member PL and projected onto the cornea of the left eye EL to be inspected. The reflected light from the cornea of the left eye EL to be inspected is deflected by the deflection member PL, passes through the objective lens 60L, passes through the beam splitters BS1L and BS3L, and is used as a ring-shaped image on the light receiving surface of the CCD21L by a CCD lens (not shown). It is imaged.

The measurement head 100 automatically executes alignment, objective measurement, subjective examination, and the like of the respective optical systems of the left eye inspection unit 120L and the right eye inspection unit 120R by controlling the control system described later. ing. The measuring head 100 may further automatically perform a binocular balance test. In the subjective test, the value (objective value) obtained by the objective measurement is used. In particular, in the cross-cylinder test among the subjective tests, the astigmatic power and the astigmatic axis angle obtained in the objective test are used.

[Control system]
Next, the control system of the ophthalmologic examination apparatus 1 of the embodiment will be described with reference to FIGS. 4 to 6. The block diagram shown in FIG. 4 shows a schematic configuration of a main part of the control system of the ophthalmologic examination apparatus 1. The block diagram shown in FIG. 5 shows a schematic configuration of a main part of the calculation unit 210 of FIG. The block diagram shown in FIG. 6 shows a schematic configuration of a main part of the corneal shape calculation unit 320 of FIG. In FIGS. 4 to 6, the same parts as those in FIGS. 1 to 3 are designated by the same reference numerals, and the description thereof will be omitted as appropriate.

As shown in FIG. 4, the control system of the ophthalmologic examination device 1 is mainly composed of a control device 200 that controls each part of the device. The control device 200 is stored in, for example, the storage unit 9. The control device 200 includes a control unit 201 and a storage unit 202.

The storage unit 202 stores a computer program for ophthalmic examination including a control program for executing a process described later, image data of an optotype pattern displayed on the LCDs 11L and 11R, and the like. In addition, the storage unit 202 stores an image of the anterior segment of the eye to be inspected, a reflex measurement result, a kerato measurement result, and the like. The image of the anterior segment of the eye to be inspected includes an image of the anterior segment acquired using the photographing optical systems 20L and 20R and an image of the anterior segment acquired using the alignment optical systems 31L and 31R. The image of the anterior segment includes an image of the anterior segment of the left eye subject EL and an image of the anterior segment of the right eye subject ER. The control unit 201 reads out the computer program stored in the storage unit 202, and sequentially executes the computer program while referring to the image data and the like stored in the storage unit 202. Such a control unit 201 includes a processor for arithmetic control such as a CPU (Central Processing Unit).

A computer device (not shown) may be connected to the ophthalmologic examination device 1. In this case, the computer device is used as a console of the ophthalmic examination device 1 and is used to accumulate and manage the examination results by the ophthalmic examination device 1. It is also possible to configure the CPU and storage device of this computer device as the control device 200.

The control device 200 (control unit 201) controls the operation of the left eye inspection unit 120L and the right eye inspection unit 120R. Specifically, the control device 200 controls a horizontal movement mechanism 111 that horizontally moves the left eye inspection unit 120L and the right eye inspection unit 120R. The control device 200 controls the rotation mechanism 112L that rotates the left eye inspection unit 120L and the vertical movement mechanism 113L that moves the left eye inspection unit 120L up and down, respectively. Similarly, the control device 200 controls the rotation mechanism 112R that rotates the right eye inspection unit 120R and the vertical movement mechanism 113R that moves the right eye inspection unit 120R up and down, respectively. The control device 200 may control the arm moving mechanism 7 that moves or rotates the lateral arm 6 up and down.

The control device 200 (control unit 201) controls the operation of the optical system housed in the left eye inspection unit 120L and the right eye inspection unit 120R. The control device 200 executes, for example, display control of the LCDs 11L and 11R, operation control of the drive mechanisms 70DL and 70DR for moving the moving lenses 70L and 70L in the optical axis direction, and the like. Display control of the LCDs 11L and 11R includes optotype switching control, optotype lighting control, optotype extinguishing control, and the like.

The control device 200 executes light receiving control by the CCDs 21L and 21R, operation control of the alignment optical systems 30L, 31L, 30R, 31R, the ref measurement optical systems 40L and 40R, the kerato measurement optical systems 50L and 50R, and the like. The left eye examination unit 120L with respect to the left eye EL so that the deviation between the position of the spot light image projected on the left eye EL by the alignment optical system 30L and the position of the pupil center of the left eye EL is cancelled. It is possible to align the optical system in the XY direction. Similarly, the alignment optical system 30R can align the optical system of the right eye inspection unit 120R with respect to the right eye test ER in the XY direction. It is possible to perform alignment in the Z direction from the parallax obtained based on the captured image of the anterior segment of the left eye EL to be inspected from two or more directions different from each other acquired by using the alignment optical system 31L. Similarly, the alignment optical system 31R can perform alignment in the Z direction from the parallax obtained based on the captured image of the anterior segment of the right eye to be inspected ER from two or more different directions. The operation control of the reflex measurement optical systems 40L and 40R includes control of a measurement light source that emits a luminous flux for reflex measurement. The operation control of the kerato measurement optical systems 50L and 50R includes the control of the keratling light source.

When each inspection unit is provided with an optical element application unit, the control device 200 (control unit 201) is a drive mechanism for selectively applying the plurality of optical elements to at least one of the left eye test EL and the right eye test ER. To control and so on.

The control device 200 (control unit 201) controls the calculation unit 210.

As shown in FIG. 6, the calculation unit 210 includes an eye refractive power calculation unit 310 and a corneal shape calculation unit 320.

The eye refractive power calculation unit 310 obtains an optical power value for each of the eye refractive power measurement using the left eye inspection unit 120L and the eye refractive power measurement using the right eye inspection unit 120R. The corneal shape calculation unit 320 obtains corneal shape information for each of the corneal shape measurement using the left eye inspection unit 120L and the corneal shape measurement using the right eye inspection unit 120R.

Hereinafter, since the operations of the optical power calculation unit 310 and the corneal shape calculation unit 320 are the same for each of the left eye test EL and the right eye test ER, either the left eye test EL or the right eye test ER will be described. To do.

The eye refractive power calculation unit 310 is based on the measurement result of the eye refractive power measurement (objective refractive power measurement) using the left eye inspection unit 120L (right eye inspection unit 120R), and the left eye examination EL (right eye examination ER). ) Is calculated as the optical power value (objective value). The eye refractive power calculation unit 310 knows, for example, the shape of the ring image acquired by receiving the ring-shaped measurement luminous flux projected on the fundus Ef by the reflex measurement optical system 40L (40R) by the CCD 21L (21R). The ocular refractive power value is obtained by analyzing with the method.

Specifically, the optical power calculation unit 310 produces a ring image (pattern image) based on the return light of the pattern light drawn on the fundus image of the eye E to be inspected, which is acquired based on the light reception result by the CCD21L (21R). To analyze.

For example, the eye refractive power calculation unit 310 obtains the brightness distribution of the acquired received light image (fundus image), and obtains the position of the center of gravity of the ring image from the obtained brightness distribution. Further, the eye refractive power calculation unit 310 obtains a brightness distribution along a plurality of scanning directions radially extending from the obtained center of gravity position, and identifies a ring image from this brightness distribution. Subsequently, the optical power calculation unit 310 obtains an approximate ellipse of the specified ring image, and substitutes the major axis and the minor axis of the approximate ellipse into a known equation to obtain the spherical power S, the astigmatic power C, and the astigmatic axis angle. Find A. In some embodiments, the equivalent spherical power SE (= S + C / 2) is calculated as the optical power value.

In some embodiments, the optical power calculation unit 310 obtains the spherical power S, the astigmatic power C and the astigmatic axis angle A, or the equivalent spherical power SE based on the deformation and displacement of the ring image with respect to the reference pattern.

The corneal shape calculation unit 320 represents the corneal shape of the left eye to be inspected EL (right eye to be inspected ER) based on the measurement result of the corneal shape measurement using the left eye inspection unit 120L (right eye inspection unit 120R). Ask for information. The corneal shape calculation unit 320, for example, obtains a ring pattern image obtained by receiving the return light of the two ring patterns projected on the cornea of the eye to be inspected by the kerato measurement optical system 50L (50R) by the CCD 21L (21R). On the other hand, a predetermined arithmetic process is performed. Thereby, it is possible to calculate a parameter representing the shape of the cornea at two positions on the two ring patterns as an objective value.

Further, the corneal shape calculation unit 320 can estimate the parameters at the extrapolated positions of the two calculated positions. Thereby, when the shape of the ring pattern image is almost a perfect circle (that is, when the shape of the cornea is almost normal), the parameters in a wide range of the cornea can be obtained by projecting the two ring patterns. .. This makes it possible to identify the shape of the cornea over a wide range with high accuracy.

Further, the corneal shape calculation unit 320 estimates the parameters of the extrapolation positions of the above two positions for each of the two or more meridians centered on the reference position (for example, the corneal center position or the alignment reference position) in the cornea. It is possible. The corneal shape calculation unit 320 approximates the parameters of the estimated two or more extrapolation positions with a predetermined function, and uses the approximated predetermined function at a predetermined position on a meridian different from the above two or more meridian lines. It is possible to estimate the parameters. Thereby, when the shape of the ring pattern image is non-circular (that is, when the shape of the cornea is abnormal), the parameters in a wide range of the cornea can be obtained by projecting the two ring patterns. This makes it possible to identify the shape of the cornea over a wide range with high accuracy.

As shown in FIG. 6, such a corneal shape calculation unit 320 includes an image identification unit 321, an image height identification unit 322, a shape information calculation unit 323, a first fitting processing unit 324, a first estimation unit 325, and a second fitting. The processing unit 326 and the second estimation unit 327 are included.

The image identification unit 321 identifies two ring pattern images based on the result of receiving the return light from the cornea on which the two ring patterns are projected. For example, the image identification unit 321 obtains the brightness distribution of the received light receiving image (anterior eye part image) acquired based on the light receiving result of the return light from the cornea, and from the obtained brightness distribution, the inside of the two ring pattern images. Find the position (center of gravity position, center position). The image specifying unit 321 obtains a luminance distribution along a plurality of scanning directions extending radially from the inner positions of the two obtained ring pattern images, and identifies the two ring pattern images from the luminance distribution.

The image height specifying unit 322 specifies the image height of each of the two ring pattern images specified by the image specifying unit 321. For example, the image height specifying unit 322 sets the height of the ring pattern image in the Y direction (vertical direction) with reference to the optical axis of the kerato measurement optical system 50L (50R) (the optical axis of the objective lens 60L (60R)). Specify as (height corresponding to the radius of the ring pattern image). In some embodiments, the position of the optical axis of the kerato measurement optical system 50L (50R) in the light receiving image substantially coincides with the inner position (center of gravity position, center position) of the two identified ring pattern images. In this case, the image height specifying unit 322 specifies the height of the ring pattern image in the Y direction (vertical direction) as the image height with reference to the position inside the two specified ring pattern images.

The shape information calculation unit 323 calculates shape information representing the shape of the cornea using the image height specified by the image height specifying unit 322.

FIG. 7 shows an operation explanatory view of the shape information calculation unit 323 according to the embodiment. FIG. 7 is a schematic representation of the ring pattern image acquired based on the light reception result by the CCD21L (21R) on the XY plane. In FIG. 7, the objective lens 60L (60R) is shown for convenience in order to show the optical axis O that serves as a reference for the image height.

Assuming that the shape of the central part of the cornea is substantially circular, the image height h of the ring pattern image formed based on the return light from the cornea on which the ring pattern of known size is projected is the surface of the cornea. It is expressed as a function of the radius of curvature R of. For example, when the return light of the ring pattern luminous flux projected from infinity at an incident angle (2 × θ) returns to the objective lens 60L (60R) as a parallel luminous flux, the inclination of the intersection (tangent plane Sp) between the corneum and the ring pattern luminous flux. dX / dY is expressed by the following equation (1).

Therefore, dX / dY is constant regardless of the radius of curvature R, and the radius of curvature R can be obtained by specifying the image height h (θ is known).

In some embodiments, the shape information calculation unit 323 uses the image height h specified by the image height specifying unit 322 to calculate the radius of curvature R as the corneal shape information at the position on the ring pattern image (1). Calculate from. The shape information calculation unit 323 calculates the radius of curvature R as the corneal shape information at each position on the two ring pattern images.

In some embodiments, the shape information calculation unit 323 calculates corneal shape information for each of the two ring pattern images as follows. That is, the slope dX / dY of the tangent plane Sp when projecting a plurality of types of ring patterns having a known size is obtained in advance using a model eye having a known radius of curvature. The shape information calculation unit 323 obtains the slope dX / dY of the tangent plane using the image height h specified by the image height specifying unit 322 for each ring pattern image, thereby obtaining a differential curve of the cross-sectional shape of the cornea to be measured. Ask for the information to represent. The shape information calculation unit 323 calculates the information representing the cross-sectional shape of the cornea by integrating the information representing the obtained differential curve of the cross-sectional shape of the cornea.

The first fitting processing unit 324 uses the position on the ring pattern image calculated by the shape information calculation unit 323 and the radius of curvature (corneal shape information) at the position as variables, and the aspherical surface with the distance from the reference position of the cornea as a variable. Fit to the function to be represented. Examples of aspherical surfaces include the conic plane, the biconic plane, and the Chebyshev polynomial plane.

Hereinafter, a case where the first fitting processing unit 324 fits the function representing the conic surface will be described. That is, the first fitting processing unit 324 sets the two positions on the two ring pattern images calculated by the shape information calculation unit 323 and the two radiuses of curvature at the two positions as the distance from the reference position of the cornea. Fit to a function that represents the cornea surface as a variable.

8A and 8B show operation explanatory views of the first fitting processing unit 324 and the first estimation unit 325 according to the embodiment. FIG. 8A schematically shows the two ring pattern images RP1, the two positions X1 and X2 on the RP2, and the extrapolation position X3. FIG. 8B schematically shows a conic surface fitted by the first fitting processing unit 324.

As shown in FIG. 8A, the shape information calculation unit 323 obtains the radius of curvature r1 and r2 at the two positions X1 and X2, which are the intersections of the ring pattern images RP1 and RP2 and the straight line passing through the reference position O1 of the cornea. The first fitting processing unit 324 approximates the surface of the cornea using a function representing the conic plane in order to estimate the radius of curvature r3 at the extrapolation position X3 on the straight line.

The function h (x) representing the image height h with respect to the distance x from the reference position O1 on the conic plane is expressed by the following equation (2). The function h (x) is a function representing a conic plane.

In equation (2), k represents the cornic constant, and A ₄ , A ₆ , and A ₈ represent the aspherical coefficient.
r ₀ represents the radius of curvature at the reference position O1. The first fitting processing unit 324, by fitting the radius of curvature r1, r2 of the two positions X1, X2 by the least squares method, conic constant (k), the aspherical surface coefficients _{(A 4, A 6, A} 8), The radius of curvature (r ₀ ) at the reference position O1 is obtained.

Specifically, the first fitting processing unit 324 has a conic constant (k), an aspherical coefficient (A ₄ , A ₆ , A ₈ ), and a radius of curvature at the reference position O1 so that the equation (3) is minimized. Find (r ₀ ). In the formula (3), n represents the number of ring pattern image, r _i represents the radius of curvature determined from the image height h _i at the distance x _i.

When the function representing the conic surface is expressed as in Eq. (2), the first fitting processing unit 324 solves Eqs. (4) to (8) to obtain the conic constant (k) and the aspherical coefficient ( _{a 4, a 6, a 8} ), determine the radius of curvature _{(r 0)} at the reference position O1.

The function r (x) representing the radius of curvature r with respect to the distance x from the reference position O1 in the cornic surface CM shown in FIG. 8B can be obtained by modifying the equation (2) obtained as described above. Using the function r (x), it is possible to obtain the radius of curvature r at a desired distance from the reference position O1.

The first estimation unit 325 estimates the radius of curvature r3 (corneal shape information) at the extrapolation positions X3 (see FIG. 8B) of the two positions X1 and X2. The function r (x) specified by the cornic constant, the aspherical coefficient, and the radius of curvature obtained by the first fitting processing unit 324 corresponds to the cornic surface CM as shown in FIG. 8B. By using the function (r) corresponding to the conic surface CM, the radius of curvature at a position at an arbitrary distance from the reference position O1 can be obtained. The first estimation unit 325 calculates the radius of curvature at the extrapolation position X3 using the function r (x), and estimates the calculated radius of curvature r3 as the radius of curvature at the extrapolation position X3.

When the shape of the cornea is almost normal, the ring pattern image becomes a substantially perfect circle. As a result, the radius of curvature estimated at the extrapolation position X3 can be used as it is.

If the shape of the cornea is abnormal, the ring pattern image will be non-circular. In this case, it is possible to fit a plurality of radiuses of curvature estimated at a plurality of extrapolated positions with a predetermined function (for example, trigonometric function) and estimate the radius of curvature at other positions using the obtained function. is there.

9A and 9B show operation explanatory views of the second fitting processing unit 326 and the second estimation unit 327 according to the embodiment. FIG. 9A schematically shows a plurality of extrapolation positions X3-1, X3-2, ... On a plurality of meridian lines centered on the reference position O1 of the cornea. FIG. 9B schematically shows a trigonometric function fitted by the second fitting processing unit 326.

The shape information calculation unit 323 has two positions (for example, positions X1-1 and X2-1) that are intersections of the ring pattern images RP1 and RP2 and the meridian for each of the plurality of meridians centered on the reference position O1 of the cornea. ) Is the radius of curvature (for example, r1-1, r2-1). The radius of curvature at the intersection of the ring pattern image and the meridian is obtained in the same manner as in FIG. 8A. As a result, the radius of curvature r1-1, r2-1 at the intersection of the ring pattern images RP1 and RP2 and the meridian passing through the two positions X1-1 and X2-1, the ring pattern images RP1 and RP2 and the two positions X1-2. , Curvature radii r1-2, r2-2, ..., Ring pattern images RP1, RP2 and two positions X1-N (N is the total number of meridian lines), X2-N at the intersection with the meridian passing through X2-2. The radius of curvature r1-N and r2-N at the intersection with the passing meridian are obtained.

Subsequently, the first fitting processing unit 324 estimates the extrapolation positions X3-1, X3-2, ..., X3-N on the meridian for the obtained radius of curvature for each of the plurality of meridians. Fits to a function that represents the conic plane of. As described above, the first fitting processing unit 324 has a function r (x) that represents the radius of curvature r with respect to the distance x from the reference position O1 on the cornic surface CM from the function h (x) that represents the conic surface obtained for each meridian. ). The first estimation unit 325 obtains the radius of curvature at the extrapolation position on the meridian using the obtained function r (x) for each meridian, so that the extrapolation positions X3-1, X3-2, ... , X3-N of curvature radii r3-1, r3-2, ..., R3-N are acquired (FIG. 9A).

The second fitting processing unit 326 has the radius of curvature r3-1, r3-2 at the extrapolation positions X3-1, X3-2, ..., X3-N on the plurality of meridian lines obtained by the first estimation unit 325. , ..., R3-N is fitted to the periodic function with the angle of the meridian as a variable. An example of a periodic function is a trigonometric function. The second fitting processing unit 326 has two or more extrapolation positions X3-1 to X3-N obtained by the first estimation unit 325 and two or more radiuses of curvature r3-1 to r3 at the two or more extrapolation positions. -N is fitted to a trigonometric function with the angle of the meridian as a variable.

Similar to the first fitting processing unit 324, the second fitting processing unit 326 fits the radius of curvature at two or more extrapolated positions by the method of least squares, so that the coefficients, phases, and constants of a known expression representing a trigonometric function are expressed. It is possible to find.

The second estimation unit 327 estimates the strong main meridian, the weak main meridian, and the axial angle by using the trigonometric function obtained by the second fitting processing unit 326. For example, when a trigonometric function as shown in FIG. 9B is obtained, the second estimation unit 327 estimates the maximum value of the radius of curvature as the strong main meridian, the minimum value of the radius of curvature as the weak main meridian, and the curvature. The angle of the meridian with the minimum radius is estimated as the axial angle. This makes it possible to identify the shape of the cornea over a wide range of the cornea by projecting the two ring patterns onto the cornea, and to identify the astigmatic state of the cornea with high accuracy.

The arithmetic unit 210 having the above configuration reads out the computer program stored in the storage unit 202 or a storage unit (not shown), and sequentially executes the computer program while referring to the data stored in the storage unit. The following functions are realized. Such a calculation unit 210 includes a calculation control processor such as a CPU.

In addition to the above-mentioned control, the control device 200 executes all operation control and data processing of the ophthalmologic examination device 1.

The control device 200 can be connected to the examiner controller 250 and the examinee controller 260 via a wired or wireless communication path, respectively. The control device 200 controls each part of the ophthalmologic examination device 1 by receiving an operation signal corresponding to the operation content for the examiner controller 250 and the subject controller 260. The control device 200 can display an operation screen, various information for performing measurement, and the like on the display unit of the examiner controller 250 and the examinee controller 260.

The control device 200 and the arithmetic unit 210 may be configured to include, for example, a microprocessor, RAM, ROM, a hard disk drive, a communication interface, and the like. The calculation unit 210 may be included in the control device 200.

Since the operating principle of alignment using the above-mentioned optical system, the measuring principle of subjective inspection, and the like are already known, detailed description thereof will be omitted.

The function of the first optotype presenting unit 122L is realized by the optotype presenting optical system 10L included in the left eye examination unit 120L. The function of the second optotype presenting unit 122R is realized by the optotype presenting optical system 10R included in the inspection unit 120R for the right eye. The function of the first objective measurement unit 123L is realized by the reflex measurement optical system 40L and the kerato measurement optical system 50L included in the left eye inspection unit 120L. The function of the second objective measurement unit 123R is realized by the reflex measurement optical system 40R and the kerato measurement optical system 50R included in the right eye inspection unit 120R.

The control device 200 and the calculation unit 210 are examples of the “ophthalmic information processing device” according to the embodiment. The ophthalmic examination device 1 is an example of the "ophthalmic device" according to the embodiment. The kerato measurement optical systems 50L and 50R, the image identification unit 321 and the image height identification unit 322, and the shape information calculation unit 323 are examples of the “acquisition unit” according to the embodiment. The first estimation unit 325, or the first estimation unit 325 and the second estimation unit 327 are examples of the "estimation unit" according to the embodiment. The refraction measurement optical systems 40L and 40R are examples of the “refractive power measurement optical system” according to the embodiment. The kerato measurement optical systems 50L and 50R are examples of the "corneal shape measurement optical system" according to the embodiment. The shape information calculation unit 323 is an example of the “corneal shape information calculation unit” according to the embodiment.

[Operation example]
Next, the operation of the ophthalmologic examination apparatus 1 according to the embodiment will be described.

10 to 12 show a flow chart of an operation example of the ophthalmic examination apparatus 1. FIG. 10 shows a flow of an overall operation example of the ophthalmologic examination apparatus 1. FIG. 11 shows a flow of a specific operation example when the ring pattern image acquired in step S2 of FIG. 10 is a substantially perfect circle. FIG. 12 shows a flow of a specific operation example when the ring pattern image acquired in step S2 of FIG. 10 is a non-perfect circle.

10 to 12 show an examination flow for the left eye-examined EL unless otherwise specified, but the examination flow for the right eye-examined ER is the same as the examination flow for the left eye-examined EL. In some embodiments, at least part of the test flow for the left eye EL is performed at the same time as at least part of the test flow for the right eye ER. The storage unit 202 stores a computer program for realizing the processes shown in FIGS. 10 to 12. The control unit 201 (control device 200) executes the processes shown in FIGS. 10 to 12 by operating according to this computer program.

(S1: Alignment)
The control unit 201 executes alignment control for the left and right eyes. That is, the control unit 201 uses the alignment optical system 30L to perform alignment of the optical system of the left eye inspection unit 120L with respect to the left eye EL to be inspected in the XY direction. Further, the control unit 201 uses the alignment optical system 30R to perform alignment of the optical system of the right eye inspection unit 120R with respect to the right eye examination ER in the XY direction.

Subsequently, the control unit 201 executes alignment of the optical system of the left eye examination unit 120L with respect to the left eye examination EL in the Z direction based on the two eye examination images acquired by using the alignment optical system 31L. Further, the control unit 201 executes alignment of the optical system of the right eye examination unit 120R with respect to the right eye examination ER in the Z direction based on the two eye examination images acquired by using the alignment optical system 31R.

(S2: Corneal shape measurement)
Next, the control unit 201 executes the corneal shape measurement. Step S2 will be described later.

In the control unit 201, the corneal shape information calculated in step S2 is stored in the storage unit 202. The operation of the ophthalmologic examination device 1 shifts to step S3 by the instruction from the control unit 201 or the user's operation or instruction to the operation unit (not shown).

(S3: Measurement of optical power)
Subsequently, the control unit 201 executes the refractive power measurement.

In the optical power measurement, the control unit 201 projects a ring-shaped measurement pattern luminous flux for measuring the optical power on the left eye EL (right eye ER) as described above. A ring image based on the return light of the measurement pattern luminous flux of the left eye to be inspected EL (right eye to be inspected ER) is formed on the imaging surface of the CCD21L (21R). The control unit 201 determines whether or not a ring image based on the return light from the fundus Ef detected by the CCD 21L (21R) could be acquired. For example, the control unit 201 detects the position (pixel) of the edge of the image based on the return light detected by the CCD21L (21R), and whether the width of the image (difference between the outer diameter and the inner diameter) is equal to or more than a predetermined value. Judge whether or not. Alternatively, the control unit 201 may determine whether or not the ring image can be obtained by determining whether or not the ring can be formed based on a point (image) having a predetermined height (ring diameter) or more. Good.

When it is determined that the ring image can be acquired, the optical power calculation unit 310 analyzes the ring image based on the return light of the measurement pattern luminous flux projected on the left eye subject EL (right eye subject ER) by a known method. .. The control unit 201 further moves the LCD 11L (11R) to the cloud fog position, and then reacquires the ring image as the main measurement. The control unit 201 causes the eye refractive power calculation unit 310 to calculate the spherical power, the astigmatic power, and the astigmatic axis angle (eye refractive power value) from the analysis result of the ring image obtained in the same manner as described above.

In the control unit 201, the eye refractive power value and the like are stored in the storage unit 202. The operation of the ophthalmologic examination device 1 shifts to step S4 by an instruction from the control unit 201 or a user's operation or instruction to an operation unit (not shown).

When it is determined that the ring image cannot be obtained, the control unit 201 considers the possibility of an abnormally intense refraction eye and sets the focusing lens (not shown) to the minus power side (for example, -10D) by a preset step. It is possible to move to the frequency side (for example, + 10D). The control unit 201 detects a ring image at each position. When it is determined that the ring image cannot be acquired even after that, the control unit 201 executes a predetermined measurement error process. At this time, the operation of the ophthalmologic examination apparatus 1 may shift to step S4. In the control unit 201, information indicating that the ocular refractive power measurement result was not obtained is stored in the storage unit 202.

(S4: Awareness test)
Next, the control unit 201 executes a subjective test.

Specifically, the control unit 201 moves the moving lens 70L (70R) to a position corresponding to the result of the objective measurement in steps S2 and S3, and displays an optotype for subjective examination on the LCD 11L (11R). Let me. At this time, the control unit 201 can control the optical system so that this astigmatic state is corrected based on the astigmatic state (astigmatism power, astigmatic axis angle) of the eye E to be inspected obtained by objective measurement. Is. For example, astigmatism can be corrected by controlling the VCS lens.

When the optotype is selected by the examiner or the control unit 201, the control unit 201 drives the LCD 11L (11R) to display a desired optotype. The light from this optotype is projected onto the fundus Ef.

The subject responds to the optotype projected on the fundus Ef. For example, in the case of a visual acuity chart, the visual acuity value of the eye to be examined is determined by the response of the subject. For example, in the case of an astigmatism test, a dot chart is displayed, and the astigmatism power of the left eye test EL (right eye test ER) is determined by the response of the subject. The selection of the optotype and the response of the subject to it are repeatedly performed at the discretion of the examiner or the control unit 201. The examiner or the control unit 201 determines the visual acuity value or the prescription value (S, C, A) based on the response from the examinee.

This completes the operation of the ophthalmologic examination device 1 (end).

When the ring pattern image acquired in step S2 of FIG. 10 is a substantially perfect circle, the corneal shape calculation unit 320 operates according to the flow shown in FIG. 11 in step S2.

(S11: Project ring pattern)
For example, the control unit 201 causes the LCD 11L (11R) to display a fixation target for measuring the shape of the cornea. After that, the control unit 201 turns on the keratling light source. When light is output from the keratling light source, two ring patterns are projected onto the cornea of the left eye subject EL (right eye subject ER).

(S12: Return light is detected)
The return light of the two ring patterns projected on the cornea in step S11 is imaged on the imaging surface of the CCD21L (21R) of the photographing optical system 20L (20R). By controlling the CCD 21L (21R), the control unit 201 acquires a light receiving image formed on the imaging surface of the CCD 21L (21R).

(S13: Specify the ring pattern image)
Next, the control unit 201 causes the image identification unit 321 to specify the two ring pattern images drawn on the light receiving image acquired in step S12 as described above.

(S14: Specify the image height)
Subsequently, the control unit 201 causes the image height specifying unit 322 to specify the image height of the ring pattern image specified in step S13 as described above.

(S15: Calculate the radius of curvature)
Next, the control unit 201 causes the shape information calculation unit 323 to calculate the radius of curvature as the corneal shape information from the image height specified in step S14 as described above.

(S16: Approximate to the conic surface)
After that, the control unit 201 controls the first fitting processing unit 324 to represent the position of the ring pattern image for which the radius of curvature was calculated in step S15 and the calculated radius of curvature for the conic surface as described above. Let the function fit.

(S17: Estimate the radius of curvature of the extrapolation position)
Next, the control unit 201 causes the first estimation unit 325 to estimate the radius of curvature at the extrapolation position by using the function representing the conic plane obtained in step S16. This completes the process of step S2 in FIG. 10 (end).

As described above, the corneal shape calculation unit 320 calculates the information representing the corneal shape for each of the left eye test EL and the right eye test ER. That is, the corneal shape calculation unit 320 calculates the radius of curvature (corneal shape information) at the positions on the two ring pattern images for each of the left eye test EL and the right eye test ER, and extrapolates the two positions. Estimate the radius of curvature at.

When the ring pattern image acquired in step S2 of FIG. 10 is a non-perfect circle, the corneal shape calculation unit 320 operates according to the flow shown in FIG. 12 in step S2.

(S21: Project ring pattern)
For example, the control unit 201 causes the LCD 11L (11R) to display a fixation target for measuring the shape of the cornea. After that, the control unit 201 turns on the keratling light source in the same manner as in step S11. As a result, two ring patterns are projected onto the cornea of the left eye to be inspected EL (right eye to be inspected ER).

(S22: Return light is detected)
The control unit 201 acquires a light receiving image formed on the imaging surface of the CCD 21L (21R) by controlling the CCD 21L (21R) in the same manner as in step S12.

(S23: Specify the ring pattern image)
Next, the control unit 201 causes the image identification unit 321 to specify the two ring pattern images drawn on the light receiving image acquired in step S22, as in step S13.

(S24: Specify the image height)
Subsequently, the control unit 201 causes the image height specifying unit 322 to specify the image height of the ring pattern image specified in step S23 for the predetermined meridian in the same manner as in step S14.

(S25: Calculate the radius of curvature)
Next, the control unit 201 causes the shape information calculation unit 323 to calculate the radius of curvature as the corneal shape information from the image height specified in step S24, as in step S15.

(S26: Approximate to the conic surface)
After that, the control unit 201 controls the first fitting processing unit 324 in the same manner as in step S16, so that the position of the ring pattern image whose radius of curvature is calculated in step S25 and the radius of curvature are represented by a conic surface. Let the function fit.

(S27: Estimate the radius of curvature of the extrapolation position)
Next, the control unit 201 causes the first estimation unit 325 to estimate the radius of curvature at the extrapolation position by using the function representing the conic plane obtained in step S26, as in step S17.

(S28: Next meridian?)
Subsequently, the control unit 201 calculates the radius of curvature on the ring pattern image and the extrapolation position for the next meridian (the meridian rotated by a predetermined angle around the center position of the cornea with respect to the current meridian). It is determined whether or not to estimate the radius of curvature in.

For example, the control unit 201 calculates and extrapolates the radius of curvature on the ring pattern image for the next meridian by determining whether or not the estimated number of radiuses of curvature at the extrapolation position has reached a predetermined number. Determine whether to estimate the radius of curvature at the position. For example, the control unit 201 calculates the radius of curvature on the ring pattern image and extrapolates the position of the next meridian by determining whether or not the angle of the meridian to be processed next has reached a predetermined angle. It is determined whether or not to estimate the radius of curvature in.

When it is determined that the next meridian is to be processed (S28: Y), the operation of the ophthalmologic examination apparatus 1 shifts to step S24. At this time, the angle of the next meridian is set to an angle rotated by a predetermined angle about the center position of the cornea with respect to the angle of the current meridian.

When it is determined that the next meridian is not processed (S28: N), the operation of the ophthalmologic examination apparatus 1 shifts to step S29.

(S29: Approximate to trigonometric function)
When it is determined in S28 that the next meridian is not processed (S28: N), the control unit 201 sets the radius of curvature at the two or more extrapolation positions acquired by repeating steps S24 to S27 in the second fitting. Let the processing unit 326 fit the trigonometric function.

(S30: Estimate strong main meridian, weak main meridian, etc.)
Subsequently, the control unit 201 causes the second estimation unit 327 to estimate the strong main meridian, the weak main meridian, and the axial angle by using the trigonometric function obtained in step S29. This completes the process of step S2 in FIG. 10 (end).

As described above, the corneal shape calculation unit 320 obtains the radius of curvature at the positions on the two ring pattern images and the radius of curvature at the extrapolation position for each of the plurality of meridian lines centered on the center position of the cornea. Estimate the radius of curvature at the above extrapolation positions. Then, the corneal shape calculation unit 320 obtains the strong main meridian, the weak main meridian, and the axial angle as described above.

<Modification example>
In the first embodiment, the case where the two ring patterns are projected onto the cornea has been described, but the configuration of the ophthalmologic examination apparatus according to the embodiment is not limited to this. The same applies to the case of projecting three or more ring patterns onto the cornea.

13A and 13B show operation explanatory views of the first fitting processing unit 324 and the first estimation unit 325 according to the modified example of the first embodiment. FIG. 13A schematically shows three positions X1, X2, X3 and extrapolation positions X4 on the three ring pattern images RP1, RP2, and RP3. FIG. 13B schematically shows a conic surface fitted by the first fitting processing unit 324. In FIGS. 13A and 13B, the same parts as those in FIGS. 8A and 8B are designated by the same reference numerals, and the description thereof will be omitted as appropriate.

In this modification, the shape information calculation unit 323 has radiuses of curvature r1, r2, r3 at three positions X1, X2, and X3, which are intersections between the ring pattern images RP1, RP2, and RP3 and a straight line passing through the reference position O1 of the cornea. Ask for. The first fitting processing unit 324 approximates the surface of the cornea using a function representing the conic surface in order to estimate the radius of curvature r4 at the extrapolation position X4 on the straight line.

It is possible to obtain the radius of curvature r at a desired distance from the reference position O1 by using the function r (x) (see FIG. 13B) obtained in the same manner as in the first embodiment. That is, the first estimation unit 325 estimates the radius of curvature r4 (corneal shape information) at the extrapolation positions X4 (see FIG. 13B) of the three positions X1, X2, and X3 using the function r (x).

When the shape of the cornea is almost normal, the radius of curvature estimated at the extrapolation position X4 can be used as it is.

When the shape of the cornea is abnormal, as in the first embodiment, a plurality of radiuses of curvature estimated at a plurality of extrapolated positions are fitted by a predetermined function (for example, trigonometric function), and the obtained function is used. It is possible to estimate the radius of curvature at other positions.

FIG. 14 shows an operation explanatory view of the second fitting processing unit 326 and the second estimation unit 327 according to the modified example of the first embodiment. FIG. 14 schematically shows a plurality of extrapolation positions X4-1, X4-2, ... On a plurality of meridian lines centered on the reference position O1 of the cornea.

The shape information calculation unit 323 has three positions (for example, positions X1-1 and X2) that are intersections of the ring pattern images RP1, RP2, and RP3 and the meridians for each of the plurality of meridians centered on the reference position O1 of the cornea. The radius of curvature (for example, r1-1, r2-1, r3-1) at -1, X3-1) is obtained. As a result, the radius of curvature r1-1, r2-1, r3-1 at the intersection of the ring pattern images RP1, RP2, RP3 and the meridian passing through the three positions X1-1, X2-1, X3-1, and the ring pattern image. Radius of curvature r1-2, r2-2, r3-2, ..., Ring pattern image RP1, at the intersection of RP1, RP2, RP3 and the meridian passing through the three positions X1-2, X2-2, X3-2, The radius of curvature r1-N, r2-N, r3-N at the intersection of RP2, RP3 and the meridian passing through the three positions X1-N, X2-N, X3-N is obtained.

Subsequently, the first fitting processing unit 324 is a function representing a cornic surface for estimating extrapolation positions X4-1, X4-2, ..., X4-N on the meridians for each of the plurality of meridians. Fit. As described above, the first fitting processing unit 324 has a function r (x) that represents the radius of curvature r with respect to the distance x from the reference position O1 on the cornic surface CM from the function h (x) that represents the conic surface obtained for each meridian. ). The first estimation unit 325 obtains the radius of curvature at the extrapolation position on the meridian using the obtained function r (x) for each meridian, so that the extrapolation positions X4-1, X4-2, ... , X4-N, the radii of curvature r4-1, r4-2, ..., R4-N are acquired (FIG. 14).

The second fitting processing unit 326 has the radius of curvature r4-1, r4-2 at the extrapolation positions X4-1, X4-2, ..., X4-N on the plurality of meridians obtained by the first estimation unit 325. , ..., R4-N is fitted to the periodic function with the angle of the meridian as a variable. The second fitting processing unit 326 has two or more extrapolation positions X4-1 to X4-N obtained by the first estimation unit 325 and two or more radiuses of curvature r4-1 to r4 at the two or more extrapolation positions. -N is fitted to a trigonometric function with the angle of the meridian as a variable.

The second estimation unit 327 estimates the strong main meridian, the weak main meridian, and the axial angle by using the trigonometric function obtained by the second fitting processing unit 326. For example, when a trigonometric function as shown in FIG. 9B is obtained, the second estimation unit 327 estimates the maximum value of the radius of curvature as the strong main meridian, the minimum value of the radius of curvature as the weak main meridian, and the curvature. The angle of the meridian with the minimum radius is estimated as the axial angle.

<Second Embodiment>
In the first embodiment or a modification thereof, the case where the extrapolation position exists outside the position on the ring pattern image with respect to the reference position O1 has been described, but the configuration according to the embodiment is limited to this. is not it. The embodiment can also be applied when the extrapolation position is inside the position on the ring pattern image with respect to the reference position O1.

The ophthalmic apparatus according to the second embodiment projects a large-diameter ring pattern onto the cornea in order to measure the shape of the cornea under the constraints caused by the type of examination (measurement) and the arrangement of the optical system. In this case, the corneal shape information at the extrapolated position inside the projected position of the ring pattern on the cornea is estimated.

The ophthalmic apparatus according to the second embodiment can perform a plurality of examinations and measurements while sharing the objective lens. In an ophthalmic apparatus capable of performing a plurality of examinations and measurements, it is possible to reduce the size and cost of the apparatus by sharing the objective lens with a plurality of optical systems corresponding to the types of examinations and measurements.

The ophthalmic apparatus according to the second embodiment can perform eye refractive power measurement (refraction measurement) and scan measurement. In the scan measurement, the measurement result is obtained by deflecting the light for measurement, projecting the deflected light onto the eye to be inspected, and detecting the return light from the eye to be inspected. Scan measurements include measurement and imaging using optical coherence tomography (OCT), measurement and imaging using an SLO (Scanning Laser Opticscope) optical system, and the like. Hereinafter, a case where the ophthalmologic apparatus according to the embodiment performs OCT on the fundus (or anterior segment of the eye) as a scan measurement will be described.

Hereinafter, in the embodiment, the case where the swept source type OCT method is used will be described in particular. However, for an ophthalmic apparatus using another type of OCT (for example, spectral domain type, time domain type), the embodiment will be used. It is also possible to apply such a configuration.

The ophthalmic apparatus according to some embodiments further includes a subjective test optical system for performing a subjective test and an objective measurement system for performing other objective measurements. The subjective test includes a distance test, a near test, a contrast test, a glare test and other subjective refraction measurements, and a visual field test. Objective measurement includes measurement for acquiring the characteristics of the eye to be inspected and photographing for acquiring an image of the eye to be inspected. Other objective measurements include intraocular pressure measurement, fundus photography, and the like.

Hereinafter, the fundus conjugate position is a position that is optically conjugate with the fundus of the eye to be inspected in the state where the alignment is completed, and means a position that is optically conjugate to the fundus of the eye to be inspected or its vicinity. Similarly, the pupil conjugate position is a position that is optically conjugate with the pupil of the eye to be inspected in the state where the alignment is completed, and means a position that is optically conjugate with the pupil of the eye to be inspected or its vicinity. ..

Hereinafter, the working distance is assumed to be the distance from the eye to be inspected to the tip of the ophthalmic device. The tip of the ophthalmic apparatus includes, for example, a lens surface on the object side of the objective lens, or a part of the apparatus main body (housing) such as a kerato plate. In some embodiments, the working distance is the distance in the optical axis of the objective lens.

[Constitution]
15 and 16 show a configuration example of the optical system of the ophthalmic apparatus according to the second embodiment. The ophthalmic apparatus 1000z according to the embodiment includes an optical system for observing the eye E to be inspected, an optical system for inspecting the eye E to be inspected, and a dichroic mirror for wavelength-separating the optical paths of these optical systems. An anterior segment observation system 5z is provided as an optical system for observing the eye E to be inspected. An OCT optical system and a refraction measurement optical system (refractive power measurement optical system) are provided as an optical system for inspecting the eye E to be inspected.

The ophthalmic apparatus 1000z includes a Z alignment system 1z, an XY alignment system 2z, a kerato measurement system 3z, a fixation projection system 4z, an anterior segment observation system 5z, a reflex measurement projection system 6z, a reflex measurement light receiving system 7z, and an OCT optical system 8z. including. In the following, for example, the anterior segment observation system 5z uses light of 940 nm to 1000 nm, and the reflex measurement optical system (ref measurement projection system 6z, reflex measurement light receiving system 7z) uses light of 830 nm to 880 nm. It is assumed that 4z uses light of 400 nm to 700 nm and OCT optical system 8z uses light of 1000 nm to 1100 nm.

(Anterior segment observation system 5z)
The anterior segment observation system 5z captures a moving image of the anterior segment of the eye E to be inspected. In the optical system passing through the anterior segment observation system 5z, the image pickup surface of the image pickup element 59z is arranged at the pupil conjugate position. The anterior segment illumination light source 50z irradiates the anterior segment of the eye E to be inspected with illumination light (for example, infrared light). The light reflected by the anterior segment of the eye E to be inspected passes through the objective lens 51z, passes through the dichroic mirror 52z, passes through the hole formed in the diaphragm (teresen diaphragm) 53z, and passes through the half mirror 23z. .. The light transmitted through the half mirror 23z passes through the relay lenses 55z and 56z and is transmitted through the dichroic mirror 76z. The dichroic mirror 52z synthesizes (separates) the optical path of the reflex measurement optical system and the optical path of the anterior segment observation system 5z. In the dichroic mirror 52z, the optical path synthesis surface that synthesizes these optical paths is arranged so as to be inclined with respect to the optical axis of the objective lens 51z. In the embodiment, the relay lens 56z can move along the optical axis of the anterior segment observation system 5z (or the optical axis of the relay lens 56z). The light transmitted through the dichroic mirror 76z is imaged on the image pickup surface of the image pickup device 59z (area sensor) by the imaging lens 58z. The image sensor 59z performs image pickup and signal output at a predetermined rate. The output (video signal) of the image sensor 59z is input to the processing unit 9z described later. The processing unit 9z displays the anterior segment image E'based on this video signal on the display screen 10za of the display unit 10z described later. The anterior segment image E'is, for example, an infrared moving image.

(Z alignment system 1z)
The Z alignment system 1z projects light (infrared light) for alignment of the objective lens 51z in the optical axis direction onto the eye E to be inspected. The light output from the Z alignment light source 11z is projected onto the cornea Cr of the eye E to be inspected, reflected by the cornea Cr, and imaged on the sensor surface of the line sensor 13z by the imaging lens 12z. When the position of the corneal apex changes in the optical axis direction of the anterior segment observation system 5z (the optical axis direction of the objective lens 51z), the light projection position on the sensor surface of the line sensor 13z changes. The processing unit 9z obtains the position of the corneal apex of the eye E to be inspected based on the light projection position on the sensor surface of the line sensor 13z, and controls the mechanism for moving the optical system based on this to execute Z alignment.

(XY alignment system 2z)
The XY alignment system 2z emits light (infrared light) for aligning in a direction (horizontal direction (X direction), vertical direction (Y direction)) orthogonal to the optical axis of the anterior segment observation system 5z. Irradiate to. The XY alignment system 2z includes an XY alignment light source 21z and a collimator lens 22z provided in an optical path branched from the optical path of the anterior segment observation system 5z by a half mirror 23z. The light output from the XY alignment light source 21z passes through the collimator lens 22z, is reflected by the half mirror 23z, and is projected onto the eye E to be inspected through the anterior segment observation system 5z. The reflected light from the corneal Cr of the eye E to be inspected is guided to the image sensor 59z through the anterior segment observation system 5z.

The image (bright spot image) Br based on this reflected light is included in the anterior segment image E'. The processing unit 9z displays the anterior segment image E'including the bright spot image Br and the alignment mark AL on the display screen of the display unit. When manually performing XY alignment, the user operates the optical system so as to guide the bright spot image Br in the alignment mark AL. When the alignment is performed automatically, the processing unit 9z controls a mechanism for moving the optical system so that the displacement of the bright spot image Br with respect to the alignment mark AL is cancelled.

(Kerato measurement system 3z)
The kerato measurement system 3z projects a ring-shaped luminous flux (infrared light) for measuring the shape of the cornea Cr of the eye E to be inspected onto the cornea Cr. The kerato plate 31z is arranged between the objective lens 51z and the eye E to be inspected. A keratling light source 32z is provided on the back side (objective lens 51z side) of the kerato plate 31z. The kerato plate 31z is formed with a kerato pattern (transmissive portion) that transmits light from the keratling light source 32z along two concentric circles centered on the optical axis of the objective lens 51z. The kerato pattern may be formed in an arc shape (a part of the circumference) centered on the optical axis of the objective lens 51z. By illuminating the kerato plate 31z with the light from the kerat ring light source 32z, two concentric ring patterns are projected onto the cornea Cr of the eye E to be inspected. The reflected light (keratling image) from the corneal Cr of the eye E to be inspected is detected by the image sensor 59z together with the anterior segment image E'. Similar to the first embodiment or its modification, the processing unit 9z calculates the corneal shape information representing the shape of the corneal Cr by performing a known calculation based on the keratling image.

(Ref measurement projection system 6z, reflex measurement light receiving system 7z)
The reflex measurement optical system includes a reflex measurement projection system 6z and a reflex measurement light receiving system 7z used for refractive power measurement. The reflex measurement projection system 6z projects a luminous flux for measuring refractive power (for example, a ring-shaped luminous flux) (infrared light) onto the fundus Ef. The reflex measurement light receiving system 7z receives the return light of this luminous flux from the eye E to be inspected. The reflex measurement projection system 6z is provided in an optical path branched by a perforated prism 65z provided in the optical path of the reflex measurement light receiving system 7z. The hole formed in the perforated prism 65z is arranged at the pupil conjugate position. In the optical system via the reflex measurement light receiving system 7z, the image pickup surface of the image pickup device 59z is arranged at the fundus conjugate position.

In some embodiments, the ref measurement light source 61z is an SLD (Superluminescent Diode) light source, which is a high-brightness light source. The reflex measurement light source 61z is movable in the optical axis direction. The reflex measurement light source 61z is arranged at the fundus conjugate position. The light output from the ref measurement light source 61z passes through the relay lens 62z and is incident on the conical surface of the conical prism 63z. The light incident on the conical surface is deflected and emitted from the bottom surface of the conical prism 63z. The light emitted from the bottom surface of the conical prism 63z passes through a light-transmitting portion formed in a ring shape on the ring diaphragm 64z. The light (ring-shaped luminous flux) that has passed through the translucent portion of the ring diaphragm 64z is reflected by the reflecting surface formed around the hole portion of the perforated prism 65z, passes through the rotary prism 66z, and is reflected by the dichroic mirror 67z. To. The light reflected by the dichroic mirror 67z is reflected by the dichroic mirror 52z, passes through the objective lens 51z, and is projected onto the eye E to be inspected. The rotary prism 66z is used for averaging the light amount distribution of the ring-shaped luminous flux with respect to the blood vessels and diseased parts of the fundus Ef and reducing speckle noise caused by the light source.

The return light of the ring-shaped luminous flux projected on the fundus Ef passes through the objective lens 51z and is reflected by the dichroic mirror 52z and the dichroic mirror 67z. The return light reflected by the dichroic mirror 67z passes through the rotary prism 66z, passes through the hole of the perforated prism 65z, passes through the relay lens 71z, is reflected by the reflection mirror 72z, and is reflected by the relay lens 73z and the focusing lens. It passes through 74z. The focusing lens 74z can move along the optical axis of the reflex measurement light receiving system 7z. The light that has passed through the focusing lens 74z is reflected by the reflection mirror 75z, reflected by the dichroic mirror 76z, and imaged on the image pickup surface of the image pickup device 59z by the imaging lens 58z. The processing unit 9z calculates the refractive power value of the eye E to be inspected by performing a known calculation based on the output from the image sensor 59z. For example, the power value includes spherical power, astigmatic power and astigmatic axis angle, or equivalent spherical power.

(Fixed projection system 4z)
An OCT optical system 8z, which will be described later, is provided in an optical path whose wavelength is separated from the optical path of the ref measurement optical system by a dichroic mirror 67z. The fixation projection system 4z is provided in the optical path branched from the optical path of the OCT optical system 8z by the dichroic mirror 83z.

The fixation projection system 4z presents the fixation target to the eye E to be inspected. The fixation unit 40z is arranged in the optical path of the fixation projection system 4z. The fixation unit 40z can move along the optical path of the fixation projection system 4z under the control of the processing unit 9z described later. The fixation unit 40z includes an LCD 41z. A relay lens 42z is arranged between the dichroic mirror 83z and the fixation unit 40z.

The LCD 41z, which is controlled by the processing unit 9z, displays a pattern representing a fixation target. By changing the display position of the pattern on the screen of the LCD 41z, the fixation position of the eye E to be inspected can be changed. The fixation position of the eye E to be inspected includes a position for acquiring an image centered on the macula of the fundus Ef, a position for acquiring an image centered on the optic nerve head, and a position between the macula and the optic nerve head. There is a position for acquiring an image centered on the center of the fundus between them. It is possible to arbitrarily change the display position of the pattern representing the fixation target.

The light from the LCD 41z passes through the relay lens 42z, passes through the dichroic mirror 83z, passes through the relay lens 82z, is reflected by the reflection mirror 81z, passes through the dichroic mirror 67z, and is reflected by the dichroic mirror 52z. The light reflected by the dichroic mirror 52z passes through the objective lens 51z and is projected onto the fundus Ef. In some embodiments, each of the LCD 41z and the relay lens 42z can move independently in the optical axis direction.

(OCT optical system 8z)
The OCT optical system 8z is an optical system for performing OCT measurement. The position of the focusing lens 87z is adjusted so that the end face of the optical fiber f1 is conjugated to the imaging site (fundus Ef or anterior segment of the eye) and the optical system based on the result of the reflex measurement performed before the OCT measurement. ..

The OCT optical system 8z is provided in an optical path whose wavelength is separated from the optical path of the reflex measurement optical system by a dichroic mirror 67z. The optical path of the fixation projection system 4z is coupled to the optical path of the OCT optical system 8z by the dichroic mirror 83z. As a result, the optical axes of the OCT optical system 8z and the fixation projection system 4z can be coaxially coupled.

The OCT optical system 8z includes an OCT unit 100z. As shown in FIG. 16, in the OCT unit 100z, the OCT light source 101z is a wavelength sweep type (wavelength scanning type) light source capable of sweeping (scanning) the wavelength of the emitted light, similarly to a general swept source type OCT device. Consists of including. The wavelength sweep type light source is configured to include a laser light source including a resonator. The OCT light source 101z changes the output wavelength with time in a near-infrared wavelength band that is invisible to the human eye.

As illustrated in FIG. 16, the OCT unit 100z is provided with an optical system for performing a swept source OCT. This optical system includes an interference optical system. This interference optical system has a function of dividing the light from the variable wavelength light source (wavelength sweep type light source) into the measurement light and the reference light, and the return light of the measurement light from the eye E to be inspected and the reference light via the reference optical path. It has a function of generating interference light by superimposing the light sources and a function of detecting the interference light. The detection result (detection signal) of the interference light obtained by the interference optical system is a signal showing the spectrum of the interference light, and is sent to the processing unit 9z.

The OCT light source 101z includes, for example, a near-infrared wavelength tunable laser that changes the wavelength of emitted light (wavelength range of 1000 nm to 1100 nm) at high speed. The light L0 output from the OCT light source 101z is guided by the optical fiber 102z to the polarization controller 103z, and its polarization state is adjusted. The light L0 whose polarization state is adjusted is guided by the optical fiber 104z to the fiber coupler 105z and divided into the measurement light LS and the reference light LR.

The reference light LR is guided by the optical fiber 110z to the collimator 111z and converted into a parallel luminous flux, and is guided to the corner cube 114z via the optical path length correction member 112z and the dispersion compensation member 113z. The optical path length correction member 112z acts to match the optical path length of the reference light LR with the optical path length of the measurement light LS. The dispersion compensating member 113z acts to match the dispersion characteristics between the reference light LR and the measurement light LS. The corner cube 114z is movable in the incident direction of the reference light LR, thereby changing the optical path length of the reference light LR.

The reference light LR that has passed through the corner cube 114z is converted from a parallel luminous flux to a focused luminous flux by the collimator 116z via the dispersion compensating member 113z and the optical path length correction member 112z, and is incident on the optical fiber 117z. The reference light LR incident on the optical fiber 117z is guided by the polarization controller 118z to adjust its polarization state, is guided to the attenuator 120z by the optical fiber 119z to adjust the amount of light, and is guided to the fiber coupler 122z by the optical fiber 121z.

On the other hand, the measurement light LS generated by the fiber coupler 105z is guided by the optical fiber f1 and converted into a parallel light beam by the collimator lens unit 89z, and passes through the optical scanner 88z, the focusing lens 87z, the relay lens 85z, and the reflection mirror 84z. Then, it is reflected by the dichroic mirror 83z.

The optical scanner 88z deflects the measurement light LS one-dimensionally or two-dimensionally. The optical scanner 88z includes, for example, a first galvano mirror and a second galvano mirror. The first galvanometer mirror deflects the measurement light LS so as to scan the imaging region (fundus Ef or anterior segment) in the horizontal direction orthogonal to the optical axis of the OCT optical system 8z. The second galvano mirror deflects the measurement light LS deflected by the first galvano mirror so as to scan the imaging region in the direction perpendicular to the optical axis of the OCT optical system 8z. For example, a pupil conjugate position is arranged between the first galvanometer mirror and the second galvanometer mirror. Examples of the scanning mode of the measured optical LS by such an optical scanner 88z include horizontal scanning, vertical scanning, cross scanning, radiation scanning, circular scanning, concentric circular scanning, and spiral scanning.

The measurement light LS reflected by the dichroic mirror 83z passes through the relay lens 82z, is reflected by the reflection mirror 81z, is transmitted through the dichroic mirror 67z, is reflected by the dichroic mirror 52z, is refracted by the objective lens 51z, and is refracted by the objective lens 51z. Incident in. The measurement light LS is scattered and reflected at various depth positions of the eye E to be inspected. The return light of the measurement light LS from the eye E to be inspected travels in the same direction as the outward path in the opposite direction, is guided to the fiber coupler 105z, and reaches the fiber coupler 122z via the optical fiber 128z.

The fiber coupler 122z combines (interferes with) the measurement light LS incidented through the optical fiber 128z and the reference light LR incidented via the optical fiber 121z to generate interference light. The fiber coupler 122z generates a pair of interference light LCs by branching the interference light at a predetermined branching ratio (for example, 1: 1). The pair of interference light LCs are guided to the detector 125z through optical fibers 123z and 124z, respectively.

The detector 125z is, for example, a balanced photodiode. The balanced photodiode includes a pair of photodetectors that detect each pair of interference light LCs, and outputs the difference between the pair of detection results obtained by these photodetectors. The detector 125z sends this output (detection signal) to the DAQ (Data Acquisition System) 130z.

A clock KC is supplied to the DAQ 130z from the OCT light source 101z. The clock KC is generated in the OCT light source 101z in synchronization with the output timing of each wavelength swept within a predetermined wavelength range by the tunable light source. The OCT light source 101z optically delays one of the two branched lights obtained by branching the light L0 of each output wavelength, and then sets the clock KC based on the result of detecting the combined light. Generate. The DAQ130z samples the detection signal input from the detector 125z based on the clock KC. The DAQ130z sends the sampling result of the detection signal from the detector 125z to the arithmetic processing unit 220z of the processing unit 9z. The arithmetic processing unit 220z forms a reflection intensity profile in each A line by, for example, performing a Fourier transform or the like on the spectral distribution based on the sampling data for each series of wavelength scans (for each A line). Further, the arithmetic processing unit 220z forms image data by imaging the reflection intensity profile of each A line.

In this example, the corner cube 114z for changing the length of the optical path (reference optical path, reference arm) of the reference optical path LR is provided, but the measured optical path length and the reference optical path length are provided by using optical members other than these. It is also possible to change the difference with.

The processing unit 9z calculates a refractive power value from the measurement result obtained by using the reflex measurement optical system, and based on the calculated refraction power value, the fundus Ef, the reflex measurement light source 61z, and the image pickup element 59z are coupled. Each of the refraction measurement light source 61z and the focusing lens 74z is moved in the optical axis direction to the position. In some embodiments, the processing unit 9z moves the focusing lens 87z of the OCT optical system 8z in the optical axis direction in conjunction with the movement of the focusing lens 74z. In some embodiments, the processing unit 9z moves the LCD 41z (fixation unit 40z) in the optical axis direction in conjunction with the movement of the reflex measurement light source 61z and the focusing lens 74z.

The ophthalmic apparatus 1000z according to the embodiment uses the reflex measurement (ocular refractive power measurement) and the OCT optical system 8z using the reflex measurement optical system while sharing the objective lens in at least the reflex measurement optical system and the OCT optical system 8z. It is possible to change the working distance with OCT measurement. As a result, it is possible to obtain a highly accurate reflex measurement result and a highly accurate OCT measurement result with a simple configuration while securing a scan range by the OCT optical system 8z.

[Operating distance when performing reflex measurement]
In the ophthalmic apparatus 1000z, the working distance (first working distance) is set so as not to be affected by the myopia of the instrument when performing the ref measurement. This working distance is a working distance at which it is possible to obtain kerato measurement results useful for corneal shape analysis.

FIG. 17 shows an explanatory diagram of the working distance when the ref measurement according to the second embodiment is performed. FIG. 17 is an enlarged view of a part of the optical system of FIG. In FIG. 17, the same parts as those in FIG. 15 are designated by the same reference numerals, and the description thereof will be omitted as appropriate.

The kerato measurement system 3z is telecentric optics so that a keratling image whose image height does not change even if the working distance changes can be acquired. When light is projected onto the cornea Cr by the kerato measurement system 3z, the cornea acts as a convex mirror, and an image reflected mainly on the front surface of the cornea Cr appears.

The radius of curvature of the cornea Cr of the eye E to be inspected is R, the image height of the keratling image with respect to the optical axis of the objective lens 51z is h1, and the projection angle of the ring-shaped luminous flux with respect to the optical axis is α. In order for the ring pattern (measurement pattern) to be placed at the incident position of the ring-shaped luminous flux from the keratling light source 32z, the angle formed by the line connecting the center of curvature of the cornea Cr and the incident position with the optical axis is β. , The following equations (9) to (10) are established.

The radius of the kerato pattern formed on the kerato plate 31z is H, the distance from the kerato plate 31z to the eye E (corneal apex) is the working distance WDref, and the distance Δd (=) between the incident position of the ring-shaped luminous flux and the corneal apex. considering the ^{R-√ (R 2 -h1 2} )), the following equation (11) holds.

From the above, in the ophthalmic apparatus 1000z according to the embodiment, when the reflex measurement is performed, the working distance WDref represented by the following formula (12) is set. The equation (12) can be obtained by substituting the equations (9) and (10) into the equation (11).

In some embodiments, known data such as a model eye is used for the radius of curvature R. The effective diameter D of the objective lens 51z can be determined from the radius H of the ring pattern.

For example, h1 = 1.5 mm in order to measure the corneal shape in the area of φ3 on the corneal Cr, which is useful for corneal shape analysis.

As described above, by setting the working distance WDref shown in the equation (12) when performing the ref measurement, the working distance is lengthened to reduce the influence of myopia of the instrument, and the size of the kerato plate 31z is increased. Can be prevented. Thereby, it is possible to provide an ophthalmic apparatus capable of acquiring highly accurate reflex measurement results and kerato measurement results with a simple configuration.

[Operating distance when performing OCT measurement]
In the ophthalmic apparatus 1000z according to the embodiment, the working distance (second working distance) is set so that at least a scan range useful for analysis using standard data can be scanned when performing OCT measurement. The standard data is statistically derived from a large number of measurement data of normal eyes and the information of the subject of the measurement data, and is called normal eye data (normalative data) or the like. The working distance set when performing OCT measurement is the working distance that can scan the scan range (or a range wider than the scan range) when the measurement data used for deriving the above standard data is acquired. It's okay.

FIG. 18 shows an explanatory diagram of the working distance when the OCT measurement according to the embodiment is performed. FIG. 18 is an enlarged view of a part of the optical system of FIG. In FIG. 18, the same parts as those in FIG. 15 are designated by the same reference numerals, and the description thereof will be omitted as appropriate.

In order to acquire data in a desired scan range without exhaustion, the optical scanner 88z deflects the measurement light LS in each of the X and Y directions. Assuming that the scan range in the fundus Ef is the range of RA × RA, the optical scanner 88z needs to be deflected by at least RA × √2 (= SA) in each direction.

Here, the optical scanner 88z is arranged so as to be substantially conjugated with the pupil of the eye E to be inspected. The working distance is WDoct, the distance from the anterior surface of the cornea to the pupil is La, the distance from the pupil to the fundus is Le, and the distance from the kerato plate 31z (the surface on the side of the eye E to be inspected) to the main surface of the objective lens 51z. Let it be Lk. The scan range SA is calculated by the following equation (13) because of the similarity between the triangle with the pupil as the apex and the base as the radius of the objective lens 51z and the triangle with the pupil as the apex and the base as the scan range SA / 2 at the fundus Ef. ) Satisfies.

From the above, in the ophthalmic apparatus 1000z according to the embodiment, when OCT measurement is performed, the working distance WDoct shown in the following formula (14) is set.

For example, the effective diameter D of the objective lens 51z is determined from the radius H of the ring pattern as the diameter (scan diameter) of the scanning range required for scanning the scanning range SA in the objective lens 51z. In some embodiments, the distances Le, La use standard eye data, or known data such as model eyes. In some embodiments, the distance Lk is known data in the ophthalmic apparatus 1000z. In some embodiments, the distance Lk is approximately zero.

As a result, the result obtained by the OCT measurement can be compared with the existing standard data, and the existing standard data can be utilized to assist a useful judgment for the OCT measurement result.

As described above, when the OCT measurement is performed, the scan result useful for the analysis using the standard data can be obtained by setting the working distance WDoct represented by the equation (14). Thereby, it is possible to provide an ophthalmic apparatus capable of assisting a useful judgment on the OCT measurement result by utilizing the existing standard data with a simple configuration.

The ophthalmic apparatus 1000z moves the optical system relative to the eye E to be inspected in the Z direction so that the working distance is WDref when performing the ref measurement, and is covered so as to be the working distance WDoct when performing the OCT measurement. The optical system is moved relative to the optometry E in the Z direction.

In the ophthalmic apparatus 1000z having such a configuration, there is a predetermined relationship between the scan range SA, the radius H of the ring pattern, and the working distances WDref and WDoct.

When the scan range SA is widened, it is necessary to reduce the working distance WDoct while increasing the effective diameter D of the objective lens 51z as shown in the equation (13). On the other hand, as shown in the equation (11), when the working distance WDref becomes smaller, the radius H of the ring pattern becomes smaller. That is, when the effective diameter D of the objective lens 51z is increased, the radius H of the ring pattern becomes smaller.

In order to secure the scan range, it is desirable that the effective diameter D of the objective lens 51z is large. Therefore, a ring pattern having a large radius is projected onto the cornea, and the corneal shape information at the position inside the ring pattern is estimated using the corneal shape information at the position on the ring pattern image. In this case, a ring pattern larger than φ3 (h1 = 1.5 mm) can be projected onto the cornea, and corneal shape information at a position corresponding to φ3 can be acquired.

<Processing system configuration>
The configuration of the processing system of the ophthalmic apparatus 1000z will be described. An example of the functional configuration of the processing system of the ophthalmic apparatus 1000z is shown in FIG. FIG. 19 shows an example of a functional block diagram of the processing system of the ophthalmic apparatus 1000z. In FIG. 19, the same parts as those in FIGS. 15 or 16 are designated by the same reference numerals, and the description thereof will be omitted as appropriate.

The processing unit 9z controls each unit of the ophthalmic apparatus 1000z. Further, the processing unit 9z can execute various arithmetic processes. The processing unit 9z includes a processor or a processing circuit. The processing unit 9z realizes the function according to the embodiment by reading and executing a program stored in a storage circuit or a storage device, for example.

The processing unit 9z includes a control unit 210z and an arithmetic processing unit 220z. Further, the ophthalmic apparatus 1000z includes a moving mechanism 200z, a display unit 270z, an operation unit 280z, and a communication unit 290z.

The lens moving mechanism 56zD is a mechanism for moving the relay lens 56. For example, the lens moving mechanism 56zD is provided with an actuator that generates a driving force for moving the relay lens 56 and a transmission mechanism that transmits the driving force. The actuator is composed of, for example, a pulse motor. The transmission mechanism is composed of, for example, a combination of gears and a rack and pinion. The control unit 210z (main control unit 211z) controls the lens moving mechanism 56zD by sending a control signal to the actuator.

The moving mechanism 200z includes a Z alignment system 1z, an XY alignment system 2z, a kerato measurement system 3z, a fixed vision projection system 4z, an anterior segment observation system 5z, a reflex measurement projection system 6z, a reflex measurement light receiving system 7z, an OCT optical system 8z, and the like. It is a mechanism for moving the head portion in which the optical system of the above is housed in the front-back and left-right directions. For example, the moving mechanism 200z is provided with an actuator that generates a driving force for moving the head portion and a transmission mechanism that transmits the driving force. The actuator is composed of, for example, a pulse motor. The transmission mechanism is composed of, for example, a combination of gears and a rack and pinion. The control unit 210z (main control unit 211z) controls the moving mechanism 200z by sending a control signal to the actuator.

(Control unit 210z)
The control unit 210z includes a processor and controls each unit of the ophthalmic apparatus. The control unit 210z includes a main control unit 211z and a storage unit 212z. A computer program for controlling the ophthalmic apparatus is stored in the storage unit 212z in advance. The computer program includes a light source control program, a detector control program, an optical scanner control program, an optical system control program, an arithmetic processing program, a user interface program, and the like. When the main control unit 211z operates according to such a computer program, the control unit 210z executes the control process.

The main control unit 211z performs various controls of the ophthalmic apparatus as a measurement control unit. The main control unit 211z includes Z alignment system 1z, XY alignment system 2z, kerato measurement system 3z, fixation projection system 4z, anterior segment observation system 5z, reflex measurement projection system 6z, reflex measurement light receiving system 7z, and OCT optical system 8z. To control.

The control for the OCT optical system 8z includes a control of the OCT light source 101z, a control of the optical scanner 88z, a control of the focusing lens 87z, a control of the corner cube 114z, a control of the detector 125z, and a control of the DAQ 130z. Control of the OCT light source 101z includes turning on and off the light source, adjusting the amount of light, adjusting the aperture, and the like. The control of the optical scanner 88z includes control of the scanning position, scanning range, and scanning speed by the first galvanometer mirror, control of the scanning position, scanning range, and scanning speed by the second galvanometer mirror.

To control the focusing lens 87z, control the movement of the focusing lens 87z in the optical axis direction, control the movement of the focusing lens 87z to the focusing reference position corresponding to the imaging region, and the movement range corresponding to the imaging region (focus). There is movement control within the focal range). For example, the main control unit 211z may move the focusing lens 87z in conjunction with the movement of the focusing lens 74z, and then move only the focusing lens 87z based on the intensity of the interference signal.

The control of the corner cube 114z includes movement control along the optical path of the corner cube 114z. For example, the OCT optical system 8z includes a moving mechanism that moves the corner cube 114z in a direction along an optical path. Similar to the moving mechanism 200z, the moving mechanism is provided with an actuator that generates a driving force for moving the moving mechanism and a transmission mechanism that transmits the driving force. The main control unit 211z controls the moving mechanism by sending a control signal to the actuator, and moves the corner cube 114z in the direction along the optical path. Control of the detector 125z includes exposure adjustment, gain adjustment, and detection rate adjustment of the detection element. The main control unit 211z samples the signal detected by the detector 125z by the DAQ 130z, and causes the arithmetic processing unit 220z (image forming unit 223z) to perform processing such as image formation based on the sampled signal.

Further, the main control unit 211z performs a process of writing data to the storage unit 212z and a process of reading data from the storage unit 212z.

(Storage unit 212z)
The storage unit 212z stores various types of data. The data stored in the storage unit 212z includes, for example, measurement results of objective measurement, image data of tomographic images, image data of fundus images, control information referred to by the main control unit 211z, eye examination information, and the like. The eye test information includes information about the subject such as the patient ID and name, and information about the test eye such as left eye / right eye identification information. In addition, various programs and data for operating the ophthalmic apparatus are stored in the storage unit 212z.

(Calculation processing unit 220z)
The arithmetic processing unit 220z includes an eye refractive power calculation unit 221z, a corneal shape calculation unit 222z, an image formation unit 223z, and a data processing unit 224z.

The eye refractive power calculation unit 221z is a ring image (pattern image) obtained by the image sensor 59z receiving the return light of the ring-shaped luminous flux (ring-shaped measurement pattern) projected on the fundus Ef by the reflex measurement projection system 6z. ) Is analyzed. The function of the eye refractive power calculation unit 221z is the same as the function of the eye refractive power calculation unit 310.

The corneal shape calculation unit 222z calculates the corneal shape information based on the ring pattern image (kerat ring image) acquired by the anterior segment observation system 5z. The function of the corneal shape calculation unit 222z is the same as the function of the corneal shape calculation unit 320. That is, as shown in FIG. 6, the corneal shape calculation unit 222z has an image identification unit 321 and an image height identification unit 322, a shape information calculation unit 323, a first fitting processing unit 324, a first estimation unit 325, and a second fitting process. Includes part 326 and second estimation part 327.

20A and 20B show operation explanatory views of the first fitting processing unit 324 and the first estimation unit 325 according to the embodiment. FIG. 20A schematically shows the two ring pattern images RP1, the two positions X1 and X2 on the RP2, and the extrapolation position X3. FIG. 20B schematically shows a conic surface fitted by the first fitting processing unit 324.

As shown in FIG. 20A, the shape information calculation unit 323 obtains the radius of curvature r1 and r2 at the two positions X1 and X2, which are the intersections of the ring pattern images RP1 and RP2 and the straight line passing through the reference position O1 of the cornea. The first fitting processing unit 324 approximates the surface of the cornea using a function representing the conic plane in order to estimate the radius of curvature r3 at the extrapolation position X3 on the straight line.

It is possible to obtain the radius of curvature r at a desired distance from the reference position O1 by using the function r (x) representing the radius of curvature r with respect to the distance x from the reference position O1 in the cornic surface CM shown in FIG. 20B.

The first estimation unit 325 estimates the radius of curvature r3 (corneal shape information) at the extrapolation positions X3 (see FIG. 20B) of the two positions X1 and X2. The function r (x) specified by the cornic constant, the aspherical coefficient, and the radius of curvature obtained by the first fitting processing unit 324 corresponds to the cornic surface CM as shown in FIG. 20B. By using the function (r) corresponding to the conic surface CM, the radius of curvature at a position at an arbitrary distance from the reference position O1 can be obtained. The first estimation unit 325 calculates the radius of curvature at the extrapolation position X3 using the function r (x), and estimates the calculated radius of curvature r3 as the radius of curvature at the extrapolation position X3.

When the shape of the cornea is almost normal, the radius of curvature estimated at the extrapolation position X3 can be used as it is.

When the shape of the cornea is abnormal, as in the first embodiment, a plurality of radiuses of curvature estimated at a plurality of extrapolated positions are fitted by a predetermined function (for example, trigonometric function), and the obtained function is used. It is possible to estimate the radius of curvature at other positions. Since this process is the same as that of the first embodiment, the description thereof will be omitted.

The image forming unit 223z forms image data of a tomographic image of the fundus Ef based on the signal detected by the detector 125z. That is, the image forming unit 223z forms the image data of the eye E to be inspected based on the detection result of the interference light LC by the interference optical system. This process includes processing such as filtering and FFT (Fast Fourier Transform), as in the case of the conventional spectral domain type OCT. The image data acquired in this way is a data set including a group of image data formed by imaging the reflection intensity profile in a plurality of A lines (paths of each measurement light LS in the eye E to be inspected). is there.

In order to improve the image quality, it is possible to superimpose (add and average) a plurality of data sets collected by repeating scanning with the same pattern a plurality of times.

The data processing unit 224z performs various data processing (image processing) and analysis processing on the tomographic image formed by the image forming unit 223z. For example, the data processing unit 224z executes correction processing such as image brightness correction and dispersion correction. Further, the data processing unit 224z performs various image processing and analysis processing on the image (anterior eye portion image and the like) obtained by using the anterior segment observation system 5z.

The data processing unit 224z can form volume data (voxel data) of the eye E to be inspected by executing known image processing such as interpolation processing for interpolating pixels between tomographic images. When displaying an image based on volume data, the data processing unit 224z performs rendering processing on the volume data to form a pseudo three-dimensional image when viewed from a specific line-of-sight direction.

(Display unit 270z, operation unit 280z)
The display unit 270z, as a user interface unit, displays information under the control of the control unit 210z. The display unit 270z includes the display unit 10z shown in FIG.

The operation unit 280z is used as a user interface unit to operate the ophthalmic apparatus. The operation unit 280z includes various hardware keys (joysticks, buttons, switches, etc.) provided in the ophthalmic apparatus. Further, the operation unit 280z may include various software keys (buttons, icons, menus, etc.) displayed on the touch panel type display screen 10za.

At least a part of the display unit 270z and the operation unit 280z may be integrally configured. A typical example thereof is a touch panel type display screen 10za.

(Communication unit 290z)
The communication unit 290z has a function for communicating with an external device (not shown). The communication unit 290z includes a communication interface according to the connection form with the external device. An example of an external device is a spectacle lens measuring device for measuring the optical characteristics of a lens. The spectacle lens measuring device measures the power of the spectacle lens worn by the subject, and inputs this measurement data to the ophthalmic device 1000z. Further, the external device may be an arbitrary ophthalmic device, a device (reader) for reading information from a recording medium, a device (writer) for writing information on a recording medium, or the like. Further, the external device may be a hospital information system (HIS) server, a DICOM (Digital Imaging and Communication in Medicine) server, a doctor terminal, a mobile terminal, a personal terminal, a cloud server, or the like. The communication unit 290z may be provided in, for example, the processing unit 9z.

The second embodiment is not limited to the case where the two ring patterns are projected onto the cornea, as in the modified example of the first embodiment. Also in the second embodiment, it is possible to project three or more ring patterns onto the cornea.

The processing unit 9z is an example of the "ophthalmic information processing device" according to the embodiment. The ophthalmic apparatus 1000z is an example of the "ophthalmic apparatus" according to the embodiment. The kerato measurement system 3z, the image identification unit 321 and the image height identification unit 322, and the shape information calculation unit 323 are examples of the “acquisition unit” according to the embodiment. The first estimation unit 325, or the first estimation unit 325 and the second estimation unit 327 are examples of the "estimation unit" according to the embodiment. The reflex measurement projection system 6z and the reflex measurement light receiving system 7z are examples of the “refractive power measurement optical system” according to the embodiment. The kerato measurement system 3z is an example of the “corneal shape measurement optical system” according to the embodiment. The OCT optical system 8z is an example of the "inspection optical system" according to the embodiment. The shape information calculation unit 323 is an example of the “corneal shape information calculation unit” according to the embodiment.

As described above, in the second embodiment, the extrapolation position is a position on the reference position side with respect to the above two or more positions. In this case, it is possible to project a ring pattern having a large diameter and estimate the corneal shape information inside the ring pattern. As a result, it becomes possible to acquire corneal shape information in a wider range of the cornea with a small number of ring patterns.

[effect]
The effects of the ophthalmic information processing device, the ophthalmic device, the ophthalmic information processing method, and the program according to the embodiment will be described.

The ophthalmic information processing apparatus (control apparatus 200 and arithmetic unit 210, or processing unit 9z) according to some embodiments includes acquisition units (kerato measurement optical systems 50L, 50R, image identification unit 321 and image height identification unit 322, and an image height identification unit 322. Shape information calculation unit 323, or kerato measurement system 3z, image identification unit 321, image height identification unit 322, and shape information calculation unit 323) and an estimation unit (first estimation unit 325, or first estimation unit 325 and first. 2 Estimating unit 327) and. The acquisition unit acquires two or more corneal shape information at two or more positions on the cornea of the eye to be inspected. The estimation unit estimates the corneal shape information at the extrapolation position on the straight line passing through the two or more positions based on the two or more corneal shape information.

According to such a configuration, the corneal shape information at the extrapolation position can be estimated by acquiring two or more corneal shape information. Thereby, by projecting a measurement pattern for acquiring at least two corneal shape information onto the cornea, it becomes possible to acquire corneal shape information in a wider range of the cornea.

In some embodiments, the estimation unit obtains corneal shape information at extrapolated positions based on a function representing an aspherical surface approximated to a shape corresponding to two or more corneal shape information at two or more positions.

With such a configuration, it becomes possible to estimate the corneal shape information in a wider range of the cornea with high accuracy.

In some embodiments, the function representing the aspherical surface is the function representing the conic plane.

With such a configuration, it becomes possible to estimate the corneal shape information in a wider range of the cornea approximated to the conic plane with high accuracy.

In some embodiments, the two or more positions are positions on the two or more concentric ring pattern images centered on the reference position on the straight line.

According to such a configuration, by projecting two or more concentric ring patterns onto the cornea, it is possible to acquire corneal shape information in a wider range of the cornea.

In some embodiments, the acquisition unit acquires two or more corneal shape information at two or more positions on the meridian for each of the two or more meridian lines passing through the reference position, and the estimator of the two or more meridian lines. For each, the corneal shape information at the extrapolated position on the meridian passing through two or more positions is estimated, and from the predetermined function approximated based on the estimated two or more corneal shape information, a predetermined meridian different from the two or more meridian lines. Obtain corneal shape information at a predetermined position on the line.

According to such a configuration, even if there is an abnormality in the shape of the cornea, it is possible to acquire the corneal shape information in a wider range of the cornea.

In some embodiments, the given function is a trigonometric function.

According to such a configuration, even if there is an abnormality in the shape of the cornea, it is possible to acquire the corneal shape information in a wider range of the cornea by a simple process.

In some embodiments, the extrapolation position is a position opposite to the reference position side with respect to two or more positions.

According to such a configuration, it is possible to acquire the corneal shape information at the extrapolation position opposite to the reference position with respect to the two or more positions from which the corneal shape information has been acquired. As a result, for example, even when a ring pattern having a concentric circle with a small diameter centered on the reference position is projected, it is possible to estimate the corneal shape information at the extrapolated position outside the ring pattern, and a wider range of the cornea can be estimated. It becomes possible to acquire corneal shape information with.

In some embodiments, the extrapolation position is a position on the reference position side with respect to two or more positions.

According to such a configuration, it is possible to acquire the corneal shape information at the extrapolation position on the reference position side with respect to the two or more positions from which the corneal shape information has been acquired. As a result, for example, even when a ring pattern having a large diameter concentric circle centered on the reference position is projected, it is possible to estimate the corneal shape information at the extrapolated position inside the ring pattern, and a wider range of the cornea can be estimated. It becomes possible to acquire corneal shape information with.

The ophthalmic apparatus (ophthalmic examination apparatus 1) according to some embodiments includes an objective lens (60L, 60R), an optical power measurement optical system (ref measurement optical system 40L, 40R), and a corneal shape measurement optical system (kerato measurement). Optical systems 50L, 50R), an optical power calculation unit (310), a corneal shape information calculation unit (shape information calculation unit 323), and the above-mentioned ophthalmic information processing apparatus are included. The optical power measuring optical system projects light onto the eye to be inspected (left eye to be inspected EL, right to be inspected ER) via an objective lens, and detects return light from the eye to be inspected. The corneal shape measurement optical system projects two or more ring patterns centered on the reference position onto the cornea of the eye to be inspected, and detects the return light from the cornea. The optical power calculation unit calculates the refractive power of the eye to be inspected based on the return light detected in the refractive power measurement optical system. The corneal shape information calculation unit calculates two or more corneal shape information at two or more positions based on the return light detected in the corneal shape measurement optical system.

Generally, when it is necessary to secure a predetermined working distance in order to reduce the influence of myopia in the refractive power measurement, the diameter of the objective lens becomes large when a ring pattern having a predetermined diameter or more is projected. Since increasing the size of the objective lens leads to an increase in the size of the device and an increase in cost, it may be necessary to project a ring pattern having a small diameter. In such a case, the acquired corneal shape information at the two or more positions is used to estimate the corneal shape information at the extrapolation position opposite to the reference position side with respect to the two or more positions. It becomes possible to acquire corneal shape information in a wider range of.

The ophthalmic apparatus (1z) according to some embodiments includes an objective lens (51z), an inspection optical system (OCT optical system 8z), a corneal shape measurement optical system (kerato measurement system 3z), and a corneal shape information calculation unit. (Shape information calculation unit 323) and the above-mentioned ophthalmic information processing apparatus are included. The inspection optical system has an optical scanner (88z), deflects the light (measurement light LS) from the light source (OCT light source 101z) by the optical scanner, and the light deflected by the optical scanner is passed through the objective lens to the eye to be inspected. The return light from the eye to be inspected is detected. The corneal shape measurement optical system projects two or more ring patterns centered on the reference position onto the cornea of the eye to be inspected, and detects the return light from the cornea. The corneal shape information calculation unit calculates two or more corneal shape information at two or more positions based on the return light detected in the corneal shape measurement optical system.

In general, there is a trade-off between securing a predetermined working distance and widening the scanning range in order to reduce the influence of myopia in the measurement of refractive power. In such a case, when the scanning range is widened, it is difficult to reduce the diameter of the objective lens, so that it may be necessary to project a ring pattern having a large diameter. In such a case, since the acquired corneal shape information at the two or more positions is used to estimate the corneal shape information at the extrapolation position on the reference position side with respect to the two or more positions, the cornea is wider. It becomes possible to acquire corneal shape information in a range.

The ophthalmologic information processing method according to some embodiments is based on an acquisition step of acquiring two or more corneal shape information at two or more positions on the cornea of the eye to be examined and two or more corneal shape information. It includes an estimation step for estimating corneal shape information at the extrapolation position on a straight line through the position.

According to such a method, the corneal shape information at the extrapolation position can be estimated by acquiring two or more corneal shape information. Thereby, by projecting a measurement pattern for acquiring at least two corneal shape information onto the cornea, it becomes possible to acquire corneal shape information in a wider range of the cornea.

In some embodiments, the estimation step obtains corneal shape information at extrapolated positions based on a function representing an aspherical surface approximated to a shape corresponding to two or more corneal shape information at two or more positions.

According to such a method, it becomes possible to estimate the corneal shape information in a wider range of the cornea with high accuracy.

In some embodiments, the function representing the aspherical surface is the function representing the conic plane.

According to such a method, it becomes possible to estimate the corneal shape information in a wider range of the cornea approximated to the conic plane with high accuracy.

In some embodiments, the two or more positions are positions on the two or more concentric ring pattern images centered on the reference position on the straight line.

According to such a method, it is possible to acquire corneal shape information in a wider range of the cornea by projecting two or more concentric ring patterns onto the cornea.

In some embodiments, the acquisition step acquires two or more corneal shape information at two or more positions on the meridian for each of the two or more meridian lines passing through the reference position, and the estimation step is for the two or more meridian lines. For each, the corneal shape information at the extrapolation position on the meridian passing through two or more positions is estimated, and from a predetermined function approximated based on the estimated two or more corneal shape information, on a meridian different from the two or more meridian lines. Obtain corneal shape information at a predetermined position.

According to such a method, even if there is an abnormality in the shape of the cornea, it is possible to acquire the corneal shape information in a wider range of the cornea.

In some embodiments, the given function is a trigonometric function.

According to such a method, even if there is an abnormality in the shape of the cornea, it is possible to acquire the corneal shape information in a wider range of the cornea by a simple process.

In some embodiments, the extrapolation position is a position opposite to the reference position side with respect to two or more positions.

According to such a method, it is possible to acquire the corneal shape information at the extrapolation position opposite to the reference position with respect to the two or more positions from which the corneal shape information has been acquired. As a result, for example, even when a ring pattern having a concentric circle with a small diameter centered on the reference position is projected, it is possible to estimate the corneal shape information at the extrapolated position outside the ring pattern, and a wider range of the cornea can be estimated. It becomes possible to acquire corneal shape information with.

In some embodiments, the extrapolation position is a position on the reference position side with respect to two or more positions.

According to such a method, it is possible to acquire the corneal shape information at the extrapolation position on the reference position side with respect to the two or more positions from which the corneal shape information has been acquired. As a result, for example, even when a ring pattern having a large diameter concentric circle centered on the reference position is projected, it is possible to estimate the corneal shape information at the extrapolated position inside the ring pattern, and a wider range of the cornea can be estimated. It becomes possible to acquire corneal shape information with.

The program according to some embodiments causes a computer to perform each step of the ophthalmic information processing method described in any of the above.

According to such a program, the corneal shape information at the extrapolation position can be estimated by acquiring two or more corneal shape information. Thereby, by projecting a measurement pattern for acquiring at least two corneal shape information onto the cornea, it becomes possible to acquire corneal shape information in a wider range of the cornea.

[Other]
The above-described embodiment or a modification thereof is not limited to the configuration of the optical system described with reference to FIGS. 2 and 3 and the configuration and control contents of the control system described with reference to FIGS. 4 to 6. For example, objective measurement such as intraocular pressure measurement, fundus photography, OCT measurement using OCT method, subjective refraction measurement such as distance examination, near vision examination, contrast examination, glare examination, and subjective examination such as visual field examination. May be configured to be possible.

That is, the ophthalmologic examination apparatus according to the embodiment can perform distance examination, near-distance examination, contrast examination, glare examination and the like as subjective examination, and objective refraction measurement and corneal shape measurement as objective measurement. , The device may be capable of performing OCT measurement and the like. In the OCT measurement, eyeball information representing the structure of the eye to be inspected, such as the axial length, corneal thickness, anterior chamber depth, and lens thickness, may be acquired.

In some embodiments, a program is provided for causing a computer to execute the above ophthalmic information processing method. Such a program can be stored in any computer-readable recording medium. Examples of the recording medium include semiconductor memory, optical disc, magneto-optical disk (CD-ROM / DVD-RAM / DVD-ROM / MO, etc.), magnetic storage medium (hard disk / floppy (registered trademark) disk / ZIP, etc.) and the like. Can be used. It is also possible to send and receive this program through a network such as the Internet or LAN.

The configuration described above is only an example for preferably carrying out the present invention. Therefore, any modification (omission, substitution, addition, etc.) within the scope of the gist of the present invention can be appropriately applied.

1 Ophthalmic examination device 3z Kerat measurement system 5z Anterior eye observation system 6z Ref measurement Projection system 7z Ref measurement Light receiving system 8z OCT optical system 9z Processing unit 20L, 20R Imaging optical system 21L, 21R CCD
40L, 40R Ref measurement optical system 50L, 50R Kerat measurement optical system 51z, 60L, 60R Objective lens 100 Measurement head 120L Left eye inspection unit 120R Right eye inspection unit 200 Control device 210 Calculation unit 310 Ophthalmic refractive power calculation unit 320 Corneal Shape calculation unit 321 Image identification unit 322 Image height identification unit 323 Shape information calculation unit 324 1st fitting processing unit 325 1st estimation unit 326 2nd fitting processing unit 327 2nd estimation unit 1000z Ophthalmic apparatus E Eye to be inspected EL Left eye to be inspected ER Right eye

Claims (19)

An acquisition unit that acquires two or more corneal shape information at two or more positions on the cornea of the eye to be inspected, and an acquisition unit.
An estimation unit that estimates corneal shape information at extrapolation positions on a straight line passing through the two or more positions based on the two or more corneal shape information, and an estimation unit.
Ophthalmic information processing device including. The estimation unit is characterized in that it obtains the corneal shape information at the extrapolation position based on a function representing an aspherical surface approximated to a shape corresponding to the two or more corneal shape information at the two or more positions. Item 2. The ophthalmic information processing apparatus according to Item 1. The ophthalmic information processing apparatus according to claim 2, wherein the function representing the aspherical surface is a function representing a conic surface. The invention according to any one of claims 1 to 3, wherein the two or more positions are positions on two or more concentric ring pattern images centered on the reference position on the straight line. Ophthalmology information processing device. The acquisition unit acquires two or more corneal shape information at two or more positions on the meridian for each of the two or more meridians passing through the reference position.
The estimation unit estimates the corneal shape information at the extrapolation position on the meridian passing through the two or more positions for each of the two or more meridian lines, and is approximated based on the estimated two or more corneal shape information. The ophthalmic information processing apparatus according to claim 4, wherein the corneal shape information at a predetermined position on a predetermined meridian line different from the two or more meridian lines is obtained from the function of. The ophthalmic information processing apparatus according to claim 5, wherein the predetermined function is a trigonometric function. The ophthalmic information processing apparatus according to any one of claims 4 to 6, wherein the extrapolation position is a position opposite to the reference position side with respect to the two or more positions. The ophthalmic information processing apparatus according to any one of claims 4 to 6, wherein the extrapolation position is a position on the reference position side with respect to the two or more positions. With the objective lens
A refractive power measurement optical system that projects light onto the eye to be inspected through the objective lens and detects return light from the eye to be inspected.
A corneal shape measurement optical system that projects two or more ring patterns centered on the reference position onto the cornea of the eye to be inspected and detects the return light from the cornea.
An optical power calculation unit that calculates the refractive power of the eye to be inspected based on the return light detected in the refractive power measurement optical system, and an eye refractive power calculation unit.
A corneal shape information calculation unit that calculates two or more corneal shape information at the two or more positions based on the return light detected in the corneal shape measurement optical system.
The ophthalmic information processing apparatus according to claim 7,
Ophthalmic equipment including. With the objective lens
It has an optical scanner, the light from the light source is deflected by the optical scanner, the light deflected by the optical scanner is projected onto the eye to be inspected through the objective lens, and the return light from the eye to be inspected is detected. Inspection optics and
A corneal shape measurement optical system that projects two or more ring patterns centered on the reference position onto the cornea of the eye to be inspected and detects the return light from the cornea.
A corneal shape information calculation unit that calculates two or more corneal shape information at the two or more positions based on the return light detected in the corneal shape measurement optical system.
The ophthalmic information processing apparatus according to claim 8 and
Ophthalmic equipment including. The acquisition step of acquiring two or more corneal shape information at two or more positions on the cornea of the eye to be inspected, and
An estimation step for estimating corneal shape information at extrapolation positions on a straight line passing through the two or more positions based on the two or more corneal shape information, and an estimation step.
Ophthalmic information processing methods including. The estimation step is characterized in that the corneal shape information at the extrapolation position is obtained based on a function representing an aspherical surface approximated to a shape corresponding to the two or more corneal shape information at the two or more positions. Item 11. The ophthalmic information processing method according to Item 11. The ophthalmic information processing method according to claim 12, wherein the function representing the aspherical surface is a function representing a conic surface. The invention according to any one of claims 11 to 13, wherein the two or more positions are positions on two or more concentric ring pattern images centered on the reference position on the straight line. Ophthalmology information processing method. The acquisition step acquires two or more corneal shape information at two or more positions on the meridian for each of the two or more meridians passing through the reference position.
The estimation step estimates the corneal shape information at the extrapolation position on the meridian passing through the two or more positions for each of the two or more meridian lines, and is approximated based on the estimated two or more corneal shape information. The ophthalmic information processing method according to claim 14, wherein the corneal shape information at a predetermined position on a meridian different from the two or more meridians is obtained from the function of. The ophthalmic information processing method according to claim 15, wherein the predetermined function is a trigonometric function. The ophthalmic information processing method according to any one of claims 14 to 16, wherein the extrapolation position is a position opposite to the reference position side with respect to the two or more positions. The ophthalmic information processing method according to any one of claims 14 to 16, wherein the extrapolation position is a position on the reference position side with respect to the two or more positions. A program comprising causing a computer to execute each step of the ophthalmic information processing method according to any one of claims 11 to 18.

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