JP7248770B2 - ophthalmic equipment - Google Patents

Description

The present invention relates to an ophthalmic device.

2. Description of the Related Art As an ophthalmologic apparatus, an apparatus capable of measuring the eye refractive power of an eye to be examined is known. For example, by projecting a ring-shaped light beam onto the eye to be inspected, a ring-shaped measurement pattern is projected onto the fundus, the reflected light from the fundus is extracted from the center of the pupil, and the size and degree of deformation of the fundus ring image is obtained. There is known an ophthalmologic apparatus that calculates an eye refractive power value from

If the fundus ring image acquired by such an ophthalmologic apparatus is unclear due to opacification of the lens caused by eyelashes or cataracts, the reliability of the calculated eye refractive power value is lowered.

For example, in Patent Document 1, an area within a predetermined distance is extracted from an ellipse obtained by approximating the acquired ring image, and a new ring image obtained by approximating the ring image in the extracted area is disclosed. An ophthalmic device is disclosed that calculates an eye refractive power value from an ellipse.

JP 2017-051430 A

However, if the obtained ring image is not clear, it is desirable to increase the amount of light incident on the subject's eye and perform the measurement again. Therefore, re-measurement still imposes a burden on the subject.

SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and its object is to provide an ophthalmologic apparatus capable of obtaining a highly reliable eye refractive power value while reducing the burden on a subject. That's what it is.

A first aspect of the embodiment is an ophthalmologic apparatus for measuring the ocular refractive power of an eye to be examined, comprising a light source capable of being placed at a position substantially optically conjugate with the fundus of the eye to be examined by moving in the optical axis direction. a projection system for projecting the light onto the subject's eye; a light receiving system for receiving return light from the fundus of the light projected by the projection system; an analysis unit for obtaining an eye refractive power value of an eye to be examined, wherein the projection system is arranged at a position substantially optically conjugate with the pupil of the eye to be examined, and an aperture formed with a light-transmitting part having a predetermined pattern. and a conical prism disposed at a position substantially conjugate optically with the pupil, deflecting the light from the light source incident on the convex conical surface and emitting the light from the bottom surface, thereby guiding the light to the translucent portion. and the ophthalmologic apparatus for projecting the light transmitted through the light-transmitting part onto the eye to be examined.

Moreover, in the second aspect of the embodiment, in the first aspect, the projection system may include a field lens arranged between the conical prism and the diaphragm.

Further, in the third aspect of the embodiment, in the second aspect, the diaphragm may be attached to the lens surface of the field lens.

Further, in a fourth aspect of the embodiment, in the first aspect, the diaphragm may be attached to the bottom surface of the conical prism.

Further, in a fifth aspect of the embodiment, in any one of the first to fourth aspects, the aperture may be a ring aperture in which the light transmitting portion is formed in a ring shape.

Advantageous Effects of Invention According to the present invention, it is possible to provide an ophthalmologic apparatus capable of obtaining a highly reliable eye refractive power value while reducing the burden on a subject.

1 is a schematic diagram showing a configuration example of an optical system of an ophthalmologic apparatus according to an embodiment; FIG. 1 is a schematic diagram showing a configuration example of an optical system of an ophthalmologic apparatus according to an embodiment; FIG. 1 is a schematic diagram showing a configuration example of an optical system of an ophthalmologic apparatus according to an embodiment; FIG. 1 is a schematic diagram showing a configuration example of a processing system of an ophthalmologic apparatus according to an embodiment; FIG. 1 is a schematic diagram showing a configuration example of a processing system of an ophthalmologic apparatus according to an embodiment; FIG. 4 is a schematic diagram showing a flow of an operation example of the ophthalmologic apparatus according to the embodiment; FIG. It is a schematic diagram showing a configuration example of an optical system of an ophthalmologic apparatus according to a modification of the embodiment. It is a schematic diagram showing a configuration example of an optical system of an ophthalmologic apparatus according to a modification of the embodiment.

An example of an embodiment of an ophthalmologic apparatus according to the present invention will be described in detail with reference to the drawings. It should be noted that the descriptions of the documents cited in this specification and any known techniques can be incorporated into the following embodiments.

An ophthalmologic apparatus according to an embodiment can perform objective measurement and subjective examination. Objective measurement is a measurement technique that obtains information about the subject's eye using mainly physical techniques without referring to responses from the subject.

Objective measurement includes measurement for acquiring characteristics of the eye to be inspected and photographing for acquiring an image of the eye to be inspected. Objective measurements include objective refraction measurement, corneal shape measurement, intraocular pressure measurement, fundus photography, and optical interference measurement. On the other hand, subjective testing is a measurement technique that acquires information using responses from subjects. The subjective examination includes subjective refraction measurement such as distance examination, near examination, contrast examination, glare examination, and visual field examination.

An ophthalmic device according to an embodiment is capable of performing objective measurements of at least eye refractive properties.

Hereinafter, the fundus conjugate position is a position that is substantially optically conjugate with the fundus of the subject's eye after alignment is completed, and means a position that is optically conjugate with the fundus of the subject's eye or its vicinity. Similarly, the pupil conjugate position is a position that is approximately optically conjugate with the pupil of the eye to be inspected in a state in which alignment is completed, and means a position that is optically conjugate with the pupil of the eye to be inspected or in the vicinity thereof. .

<Configuration of optical system>
FIG. 1 shows a configuration example of an optical system of an ophthalmologic apparatus according to an embodiment. The ophthalmologic apparatus 1000 includes a Z alignment system 1, an XY alignment system 2, a keratometry system 3, a target projection system 4, an anterior segment observation system 5, and a reflector measurement projection system as optical systems for examining an eye E to be examined. 6, and a ref measurement light-receiving system 7.

(Anterior segment observation system 5)
The anterior segment observation system 5 captures a moving image of the anterior segment of the eye E to be examined. In the optical system passing through the anterior segment observation system 5, the imaging plane of the imaging device 59 is arranged at the pupil conjugate position Q. FIG. The anterior segment illumination light source 51 irradiates the anterior segment of the eye E to be examined with illumination light (for example, infrared light). The light reflected by the anterior segment of the subject's eye E passes through the objective lens 52, the dichroic mirror 53, the half mirror 54, the relay lenses 55 and 56, and the dichroic mirror 57. . The light transmitted through the dichroic mirror 57 is imaged on the imaging surface of the imaging device 59 (area sensor) by the imaging lens 58 . The imaging element 59 performs imaging and signal output at a predetermined rate. The output (video signal) of the imaging device 59 is input to the processing section 9 which will be described later. The processing unit 9 displays an anterior segment image based on this video signal on a display screen of a display unit, which will be described later. The anterior segment image is, for example, an infrared moving image.

(Z alignment system 1)
The Z alignment system 1 projects light (infrared light) onto the subject's eye E for alignment in the optical axis direction (front-rear direction, Z direction) of the anterior segment observation system 5 . The light output from the Z alignment light source 11 is projected onto the cornea of the subject's eye E, reflected by the cornea, and imaged on the sensor surface of the line sensor 13 by the imaging lens 12 . When the position of the corneal vertex changes in the optical axis direction of the anterior segment observation system 5, the light projection position on the sensor surface of the line sensor 13 changes. The processing unit 9 obtains the position of the corneal vertex of the subject's eye E based on the light projection position on the sensor surface of the line sensor 13, and based on this, controls the mechanism for moving the optical system to perform Z alignment.

(XY alignment system 2)
The XY alignment system 2 applies light (infrared light) to the eye to be examined E for alignment in directions perpendicular to the optical axis of the anterior eye observation system 5 (horizontal direction (X direction) and vertical direction (Y direction)). to irradiate. The XY alignment system 2 includes an XY alignment light source 21 provided on an optical path branched from the anterior eye observation system 5 by a half mirror 54 . The light output from the XY alignment light source 21 is reflected by the half mirror 54 and projected onto the subject's eye E through the anterior eye observation system 5 . Reflected light from the cornea of the subject's eye E is guided to the imaging device 59 through the anterior segment observation system 5 .

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

(Kerato measurement system 3)
The keratometry system 3 projects a ring-shaped light beam (infrared light) for measuring the shape of the cornea of the eye E to be examined onto the cornea. The keratoplate 31 is arranged between the objective lens 52 and the eye E to be examined. A kerato ring light source (not shown) is provided on the back side of the keratoplate 31 (on the objective lens 52 side). A ring-shaped light beam is projected onto the cornea of the eye E to be examined by illuminating the keratoplate 31 with the light from the keratizing light source. Reflected light (keratling image) from the cornea of the subject's eye E is detected by the imaging element 59 together with the anterior segment image. The processing unit 9 calculates corneal shape parameters representing the shape of the cornea by performing known calculations based on this keratling image.

(Target projection system 4)
The visual target projection system 4 presents various visual targets to the subject's eye E, such as a fixation target and a subjective test visual target. The light (visible light) output from the light source 41 is collimated by the collimating lens 42 and is irradiated onto the optotype chart 43 . The optotype chart 43 includes, for example, a transmissive liquid crystal panel, and displays patterns representing optotypes. The light transmitted through the optotype chart 43 passes through the relay lenses 44 and 45 , is reflected by the reflecting mirror 46 , passes through the dichroic mirror 68 , and is reflected by the dichroic mirror 53 . The light reflected by the dichroic mirror 53 passes through the objective lens 52 and is projected onto the fundus oculi Ef. The light source 41, the collimator lens 42, and the optotype chart 43 are integrally movable in the optical axis direction.

When performing a subjective test, the processing unit 9 moves the light source 41, the collimator lens 42, and the optotype chart 43 in the optical axis direction based on the result of the objective measurement, and controls the optotype chart 43. FIG. The processor 9 causes the optotype chart 43 to display the optotype selected by the examiner or the processor 9 . Thereby, the target is presented to the subject. The subject responds to the visual target. Upon receiving the input of the content of the response, the processing unit 9 performs further control and calculation of subjective test values. For example, in visual acuity measurement, the processing unit 9 selects and presents the next visual target based on the response to the Landolt's ring or the like, and repeats this to determine the visual acuity value.

(ref measurement projection system 6, ref measurement light receiving system 7)
The reflector measurement projection system 6 and the reflector measurement light receiving system 7 are used for objective refraction measurement (reflection measurement). The reflector measurement projection system 6 projects a ring-shaped light beam (infrared light) for objective measurement onto the fundus oculi Ef. The ref measurement light-receiving system 7 receives the return light from the subject's eye E of this ring-shaped light beam.

The reflector measurement light source 61 may be an SLD (Superluminescent Diode) light source, which is a high-brightness light source with an emission diameter equal to or less than a predetermined size. The ref measurement light source 61 is movable in the optical axis direction and arranged at the fundus conjugate position P. As shown in FIG. A ring diaphragm 65 (specifically, a transparent portion) is arranged at the pupil conjugate position Q. As shown in FIG. A fundus conjugate position P is arranged between the dichroic mirror 53 and the dichroic mirror 68 and between the relay lens 73 and the focusing lens 74 . The focusing lens 74 is movable in the optical axis direction. In the optical system passing through the ref measurement light-receiving system 7, the image pickup plane of the image pickup element 59 is arranged at the fundus conjugate position P. As shown in FIG.

The light output from the ref measurement light source 61 passes through the relay lens 62 and enters the conical surface of the conical prism 63 . Light incident on the conical surface is deflected and emitted from the bottom surface of the conical prism 63 . Light emitted from the bottom surface of the conical prism 63 passes through the field lens 64 and then through a ring-shaped transparent portion of the ring aperture 65 . The light (ring-shaped luminous flux) that has passed through the transparent portion of the ring diaphragm 65 is reflected by the reflecting surface of the perforated prism 66 , passes through the rotary prism 67 , and is reflected by the dichroic mirror 68 . The light reflected by the dichroic mirror 68 is reflected by the dichroic mirror 53, passes through the objective lens 52, and is projected onto the eye E to be examined. The rotary prism 67 is used for averaging the light amount distribution of the ring-shaped light flux for blood vessels and diseased areas of the fundus oculi Ef and for reducing speckle noise caused by the light source.

It is desirable that the conical prism 63 be arranged at a position as close as possible to the pupil conjugate position Q while avoiding an increase in size of the ref measurement projection system 6 .

FIG. 2 schematically shows a cross-sectional view of the field lens 64. As shown in FIG. For example, as shown in FIG. 2, a ring diaphragm 65 may be attached to the lens surface of the field lens 64 on the eye E side. In this case, for example, a light shielding film is deposited on the lens surface of the field lens 64 so as to form a ring-shaped transparent portion.

Further, the ref measurement projection system 6 may have a configuration in which the field lens 64 is omitted.

FIG. 3 schematically shows a cross-sectional view of the conical prism 63. As shown in FIG. For example, as shown in FIG. 3, a ring diaphragm 65 may be attached to the bottom surface 63b of the conical prism 63 on which the light passing through the relay lens 62 is incident on the conical surface 63a. In this case, for example, a light shielding film is deposited on the bottom surface 63b of the conical prism 63 so as to form a ring-shaped transparent portion.

The ring aperture 65 may be an aperture in which a predetermined pattern of light-transmitting portions is formed. A transparent portion may be formed in this diaphragm at a position eccentric to the optical axis of the reflector measurement projection system 6 . Also, the diaphragm may be formed with two or more translucent portions.

The return light of the ring-shaped luminous flux projected onto the fundus oculi Ef passes through the objective lens 52 and is reflected by the dichroic mirrors 53 and 68 . The return light reflected by the dichroic mirror 68 passes through the rotary prism 67, passes through the aperture of the perforated prism 66, passes through the relay lens 71, is reflected by the reflecting mirror 72, and passes through the relay lens 73 and the focusing lens. Pass 74. The light passing through the focusing lens 74 is reflected by the reflecting mirror 75 , reflected by the dichroic mirror 57 , and formed into an image on the imaging surface of the imaging device 59 by the imaging lens 58 . The processing unit 9 calculates the refractive power value of the subject's eye E by performing a known calculation based on the output from the imaging device 59 . For example, power values include spherical power, cylinder power, and cylinder axis angle.

A stop may be arranged between the apertured prism 66 and the relay lens 71 to limit the beam diameter on the pupil. The light-transmitting portion of this diaphragm is arranged at a pupil conjugate position.

Based on the calculated refractive power value, the processing unit 9 adjusts the reflex measurement light source 61 and the focusing lens 74 so that the fundus oculi Ef, the reflex measurement light source 61, and the imaging surface of the imaging element 59 are optically conjugate. are moved in the direction of the optical axis. Further, the processing section 9 moves the visual target unit along its optical axis in conjunction with the movement of the ref measurement light source 61 and the focusing lens 74 . The optotype unit including the light source 41, the collimating lens 42 and the optotype chart 43, the ref measurement light source 61, and the focusing lens 74 may be interlocked and movable in their respective optical axis directions.

<Configuration of processing system>
The configuration of the processing system of the ophthalmologic apparatus 1000 will be described. An example of the functional configuration of the processing system of the ophthalmologic apparatus 1000 is shown in FIGS. 4 and 5. FIG. FIG. 4 shows an example of a functional block diagram of the processing system of the ophthalmologic apparatus 1000. As shown in FIG. FIG. 5 shows an example of a functional block diagram of the arithmetic processing section 120 of FIG.

The processing unit 9 controls each unit of the ophthalmologic apparatus 1000 . In addition, the processing unit 9 can execute various arithmetic processing. The processing unit 9 includes a processor.プロセッサの機能は、例えば、ＣＰＵ（Ｃｅｎｔｒａｌ Ｐｒｏｃｅｓｓｉｎｇ Ｕｎｉｔ）、ＧＰＵ（Ｇｒａｐｈｉｃｓ Ｐｒｏｃｅｓｓｉｎｇ Ｕｎｉｔ）、ＡＳＩＣ（Ａｐｐｌｉｃａｔｉｏｎ Ｓｐｅｃｉｆｉｃ Ｉｎｔｅｇｒａｔｅｄ Ｃｉｒｃｕｉｔ）、プログラマブル論理デバイス（例えば、ＳＰＬＤ（Ｓｉｍｐｌｅ Ｐｒｏｇｒａｍｍａｂｌｅ Ｌｏｇｉｃ Ｄｅｖｉｃｅ）、ＣＰＬＤ（Ｃｏｍｐｌｅｘ Ｐｒｏｇｒａｍｍａｂｌｅ Ｌｏｇｉｃ Ｄｅｖｉｃｅ） , FPGA (Field Programmable Gate Array)). The processing unit 9 implements the functions according to the embodiment by, for example, reading and executing a program stored in a storage circuit or storage device.

Processing unit 9 includes control unit 110 and arithmetic processing unit 120 . The ophthalmologic apparatus 1000 also includes a display section 170 , an operation section 180 and a communication section 190 .

(control unit 110)
The control unit 110 controls each unit of the ophthalmologic apparatus 1000 . Control unit 110 includes main control unit 111 and storage unit 112 .

A main control unit 111 performs various controls of the ophthalmologic apparatus 1000 . The main controller 111 controls the Z alignment light source 11 and the line sensor 13 of the Z alignment system 1 , the XY alignment light source 21 of the XY alignment system 2 , and the keratizing light source of the keratometric measurement system 3 . As a result, the amount of light output from the Z alignment light source 11, the XY alignment light source 21, or the keratling light source is changed, or lighting and non-lighting are switched. Also, a signal detected by the line sensor 13 is captured, and alignment control or the like is performed based on the captured signal.

The main control unit 111 controls the light source 41 of the target projection system 4 and the target chart 43 . As a result, the amount of light output from the light source 41 is changed, or lighting and non-lighting are switched. In addition, the display of the optotype and fixation target in the optotype chart 43 can be turned on/off, and the optotype and fixation target can be switched. The main controller 111 can also control a movement mechanism (not shown) that moves the optotype unit including the light source 41, the collimator lens 42, and the optotype chart 43 in the optical axis direction.

The main control unit 111 controls the anterior segment illumination light source 51 and the imaging element 59 of the anterior segment observation system 5 . As a result, the amount of light output from the anterior ocular segment illumination light source 51 is changed, or lighting and non-lighting are switched. In addition, the signal acquired by the imaging element 59 is captured, and the arithmetic processing unit 120 performs image formation and the like.

The main control unit 111 controls the ref measurement light source 61 and the rotary prism 67 of the ref measurement projection system 6 and the focusing lens 74 of the ref measurement light receiving system 7 . As a result, the amount of light output from the ref measurement light source 61 is changed, or switching between lighting and non-lighting is performed. Also, the rotary prism 67 is rotated. Also, the position of the focusing lens 74 in the optical axis direction is changed. The main controller 111 can also control a moving mechanism (not shown) that moves the ref measurement light source 61 in the optical axis direction.

The main control unit 111 also performs processing of writing data to the storage unit 112 and processing of reading data from the storage unit 112 .

The storage unit 112 stores various data. The data stored in the storage unit 112 includes measurement information obtained by the keratometry system 3, measurement information obtained by the ref measurement projection system 6 and the ref measurement light receiving system 7, and an image obtained by the imaging element 59. data, eye information to be examined, and the like. The eye information to be examined includes information about the subject such as patient ID and name, and information about the eye to be examined such as left/right eye identification information. The measurement information obtained by the keratometry system 3 is stored in the storage unit 112 when the keratometry of the subject's eye E is performed by the ophthalmologic apparatus 1000 . The measurement information obtained by the reflector measurement projection system 6 and the reflector measurement light receiving system 7 is stored in the storage unit 112 when the reflector measurement of the subject's eye E is performed by the ophthalmologic apparatus 1000 . The storage unit 112 may be used as a working memory for the corneal shape parameter calculation process and the eye refractive power value calculation process. The storage unit 112 also stores various programs and data for operating the ophthalmologic apparatus 1000 .

(Arithmetic processing unit 120)
The calculation processing unit 120 executes various calculations for obtaining parameters representing eye refractive power such as, for example, corneal shape parameters and eye refractive power values. Arithmetic processing unit 120 includes analysis unit 121 .

The analysis unit 121 analyzes a ring image (pattern image) obtained by the imaging element 59 receiving the return light of the ring-shaped light beam (ring-shaped measurement pattern) projected onto the fundus oculi Ef by the reflex measurement projection system 6. do. For example, the analysis unit 121 obtains the barycentric position of the ring image from the luminance distribution in the obtained image in which the ring image is rendered, obtains the luminance distribution along a plurality of scanning directions radially extending from this barycentric position, and obtains the luminance distribution. Identify the ring image from the distribution. Subsequently, the analysis unit 121 obtains an approximate ellipse of the specified ring image, and obtains the spherical power, the cylinder power, and the cylinder axis angle by substituting the major axis and minor axis of the approximate ellipse into known formulas.

Alternatively, the analysis unit 121 can obtain eye refractive power parameters based on the deformation and displacement of the ring image with respect to the reference pattern.

The analysis unit 121 also calculates the corneal refractive power, the corneal astigmatism degree, and the corneal astigmatism axis angle based on the keratling image acquired by the anterior eye observation system 5 . For example, the analysis unit 121 calculates the corneal curvature radii of the strong principal meridian and the weak principal meridian of the corneal front surface by analyzing the keratling image, and calculates the above parameters based on the corneal curvature radii.

(Display unit 170, operation unit 180)
Display unit 170 displays information under the control of control unit 110 . The operation unit 180 is used for operating the ophthalmologic apparatus 1000 and inputting information. The operation unit 180 includes various hardware keys (joystick, buttons, switches, etc.) and/or various software keys (buttons, icons, menus, etc.) presented on the display unit 170 .

(Communication unit 190)
The communication unit 190 has a function of communicating with an external device. The communication unit 190 has a communication interface according to a connection form with an external device. An example of an external device is a spectacle lens measuring device for measuring the optical properties of lenses. The spectacle lens measuring device measures the dioptric power of the spectacle lens worn by the subject, and inputs this measurement data to the ophthalmologic device 1000 . Also, the external device may be any ophthalmologic device, a device (reader) that reads information from a recording medium, or a device (writer) that writes information to a recording medium. Furthermore, 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 reflector measurement projection system 6 is an example of the "projection system" according to the embodiment. The ref measurement light-receiving system 7 is an example of the "light-receiving system" according to the embodiment. The ring aperture 65 is an example of the "aperture" according to the embodiment. The conical prism 63 is an example of a "deflection member" according to the embodiment.

<Operation example>
The operation of the ophthalmologic apparatus 1000 according to the embodiment will be described. An example of the operation of the ophthalmologic apparatus 1000 is shown in FIG. FIG. 6 shows a flow diagram of an operation example of the ophthalmologic apparatus 1000 . In the following, it is assumed that the optotype unit including the light source 41, the collimating lens 42 and the optotype chart 43 is moved along the optical axis.

(S1: Alignment)
When the examiner performs a predetermined operation on the operation unit 180 while the subject's face is fixed to the face receiving unit (not shown), the ophthalmologic apparatus 1000 is fixed by the light source 41 and the optotype chart 43. A bright spot is projected onto the subject's eye E as a target to perform alignment.

Specifically, the main controller 111 turns on the Z alignment light source 11 , the XY alignment light source 21 and the light source 41 . The processing unit 9 acquires the imaging signal of the anterior segment image on the imaging surface of the imaging element 59 and causes the display unit 170 to display the anterior segment image. After that, the optical system shown in FIG. 1 is moved to the examination position of the eye E to be examined. The inspection position is a position at which the eye to be inspected E can be inspected with sufficient accuracy. The subject's eye E is placed at the inspection position through the above-described alignment (alignment by the Z alignment system 1, the XY alignment system 2, and the anterior segment observation system 5). Movement of the optical system is executed by the control unit 110 according to an operation or instruction by the user or an instruction by the control unit 110 . That is, the movement of the optical system to the inspection position of the subject's eye E and the preparation for objective measurement are performed.

The main control unit 111 also moves the ref measurement light source 61, the focusing lens 74, and the target unit to their origin positions (for example, a position corresponding to 0D) along their respective optical axes.

(S2: Kerato measurement)
The main control unit 111 causes the light source 41 and the optotype chart 43 to present the fixation target to the subject's eye E, and causes the keratometry to be performed.

That is, the main controller 111 turns on the keratling light source. When light is output from the keratling light source, a ring-shaped light beam for corneal shape measurement is projected onto the cornea of the eye E to be examined. The analysis unit 121 calculates the corneal curvature radius by performing arithmetic processing on the image acquired by the image sensor 59, and calculates the corneal refractive power, the corneal astigmatism degree, and the corneal astigmatism axis angle from the calculated corneal curvature radius. calculate. In the control unit 110 , the calculated corneal refractive power and the like are stored in the storage unit 112 . In response to an instruction from the main control unit 111 or a user's operation or instruction to the operation unit 180, the operation of the ophthalmologic apparatus 1000 proceeds to step S3.

(S3: Reflex measurement)
The main control unit 111 controls the light source 41 and the optotype chart 43 to present the fixation target to the subject's eye E and perform the reflex measurement.

In the reflex measurement, the main control unit 111 projects the ring-shaped measurement pattern light flux for the reflex measurement onto the eye E to be examined as described above. A ring image is formed on the imaging surface of the imaging device 59 based on the return light of the measurement pattern light flux from the eye E to be inspected. The main control unit 111 determines whether or not the ring image based on the return light from the fundus oculi Ef detected by the imaging device 59 has been acquired. For example, the main control unit 111 detects the position (pixel) of the edge of the image based on the return light detected by the imaging device 59, and determines whether the width of the image (the difference between the outer diameter and the inner diameter) is equal to or greater than a predetermined value. determine whether or not Alternatively, the main control unit 111 determines whether a ring image can be obtained by determining whether a ring can be formed based on points (images) having a predetermined height (ring diameter) or more. good too.

When it is determined that the ring image has been acquired, the analysis unit 121 analyzes the ring image based on the return light of the measurement pattern light flux projected onto the subject's eye E by a known method, and obtains the temporary spherical power and the cylindrical power. . Based on the temporary spherical power and astigmatic power, the main control unit 111 moves the ref measurement light source 61, the focusing lens 74, and the target unit to the position of the equivalent spherical power (S+C/2) (the position corresponding to the temporary far point). ). After moving the optotype unit from that position to the cloudy position, the main control unit 111 controls the ref measurement projection system 6 and the ref measurement light receiving system 7 to acquire the ring image again as the main measurement. The main control unit 111 causes the analysis unit 121 to calculate the spherical power, the cylindrical power, and the cylindrical axis angle from the analysis result of the ring image obtained in the same manner as described above and the movement amount of the focusing lens 74 .

Further, the analysis unit 121 obtains the position corresponding to the far point of the subject's eye E (the position corresponding to the far point obtained by the main measurement) from the obtained spherical power and astigmatic degree C. The main control unit 111 moves the visual target unit to the position corresponding to the obtained far point. In the control unit 110 , the position of the focusing lens 74 and the calculated spherical power are stored in the storage unit 112 . The operation of the ophthalmologic apparatus 1000 proceeds to step S4 according to an instruction from the main control unit 111 or a user's operation or instruction on the operation unit 180 .

When it is determined that the ring image cannot be acquired, the main control unit 111 considers the possibility of the eye being a highly ametropic eye, and moves the ref measurement light source 61 and the focusing lens 74 to the minus power side (for example, -10D), and move it to the plus power side (for example, +10D). The main control unit 111 controls the ref measurement light-receiving system 7 to detect the ring image at each position. If it is still determined that the ring image cannot be acquired, the main control unit 111 executes predetermined measurement error processing. At this time, the operation of the ophthalmologic apparatus 1000 may proceed to step S4. In the control unit 110, information indicating that the result of the ref measurement was not obtained is stored in the storage unit 112. FIG.

(S4: subjective measurement)
The control unit 110 displays a desired target by controlling the target chart 43 based on the user's instruction to the operation unit 180, for example. Also, the control unit 110 moves the visual target unit to a position according to the result of the objective measurement. The control section 110 may move the target unit to a position according to the user's instruction to the operation section 180 .

The subject responds to the target projected onto the fundus oculi Ef. For example, in the case of visual targets for visual acuity measurement, the visual acuity value of the subject's eye is determined according to the subject's response. The selection of the target and the subject's response thereto are repeatedly performed by the examiner or the controller 110 . The examiner or control unit 110 determines the visual acuity value or prescription value (S, C, A) based on the response from the subject, and the operation of the ophthalmologic apparatus 1000 ends (end).

As described above, the reflector measurement light source 61 is arranged at the fundus conjugate position P, the ring diaphragm 65 is arranged at the pupil conjugate position Q, and the conical prism 63 is arranged near the pupil conjugate position Q. It becomes possible to project a thin, high-brightness (narrow width between inner and outer diameters) ring-shaped measurement pattern light flux onto the fundus oculi Ef. Therefore, it is possible to reduce the light amount of the measurement pattern light flux incident on the eye to be examined E, thereby reducing the burden on the subject and obtaining a highly reliable eye refractive power value. In addition, since a narrow ring-shaped beam of light can also enter the pupil, even if part of the incident beam is blocked by the opacity of the lens due to eyelashes or cataracts, the occurrence of measurement errors and variations in measured values is minimized. be able to suppress it.

The configuration of the optical system of the ophthalmologic apparatus 1000 according to the embodiment is not limited to the configuration shown in FIG.

FIG. 7 shows a configuration example of an optical system of an ophthalmologic apparatus according to a modification of the embodiment. In FIG. 7, the same parts as in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted as appropriate.

The configuration of the ophthalmologic apparatus 1000a according to the modification differs from the configuration of the ophthalmologic apparatus 1000 in that the refractometer measurement projection system 6a is provided instead of the refractor measurement projection system 6. FIG. The configuration of the ref measurement projection system 6a differs from that of the ref measurement projection system 6 in that a ring lens 69 is provided instead of the conical prism 63 and the field lens 64. FIG. The ring lens 69 includes a central area formed as a light shielding area and a lens portion formed in a ring shape around the central area. The luminous flux incident on the ring lens 69 exits as a ring-shaped luminous flux.

In this modification, it is desirable that the ring lens 69 be arranged as close as possible to the pupil conjugate position Q while avoiding an increase in the size of the ref measurement projection system 6a.

FIG. 8 schematically shows a cross-sectional view of the ring lens 69. As shown in FIG. For example, as shown in FIG. 8, a ring diaphragm 65 is attached to the lens surface of the ring lens 69 on the eye E side. In this case, for example, a light shielding film is deposited on the lens surface of the ring lens 69 so as to form a ring-shaped transparent portion.

Since the operation of the ophthalmologic apparatus 1000a according to this modification is the same as that of the embodiment, detailed description thereof will be omitted.

In this modified example, similarly to the embodiment, it is possible to reduce the amount of light of the measurement pattern light beam incident on the eye E to be examined, thereby reducing the burden on the examinee and obtaining a highly reliable eye refractive power value. be able to In addition, since a narrow ring-shaped beam of light can also enter the pupil, even if part of the incident beam is blocked by the opacity of the lens due to eyelashes or cataracts, the occurrence of measurement errors and variations in measured values is minimized. be able to suppress it.

[Action/effect]
Actions and effects of the ophthalmologic apparatus according to the embodiment or modification will be described.

An ophthalmologic apparatus (1000, 1000a) according to an embodiment measures the eye refractive power of an eye E to be examined. The ophthalmologic apparatus includes a projection system (ref measurement projection systems 6 and 6a), a light receiving system (ref measurement light receiving system 7), and an analysis section (121). The projection system projects light from a light source (reflector measurement light source 61) arranged at a position (fundus conjugate position P) substantially optically conjugate with the fundus (Ef) of the eye to be examined. The light receiving system receives return light from the fundus of the light projected by the projection system. The analysis unit obtains an eye refractive power value of the subject's eye based on the result of receiving the returned light by the light receiving system. The projection system is arranged at a position (pupil conjugate position Q) that is optically approximately conjugate with the pupil of the eye to be examined, and includes a diaphragm (ring diaphragm 65) formed with a predetermined pattern of light-transmitting portions, and a light source. and a deflecting member (conical prism 63, ring lens 69) that deflects light and guides it to the light-transmitting portion, and projects the light transmitted through the light-transmitting portion to the eye to be inspected.

With such a configuration, it is possible to project a high-brightness and narrow (narrow width between the inner diameter and the outer diameter) measurement pattern light flux onto the fundus of the eye. It is possible to obtain a highly reliable eye refractive power value while reducing the burden on the subject. In addition, since it is possible to enter the pupil with a narrow measuring pattern light beam, even if part of the incident light beam is blocked by the opaque part of the lens caused by eyelashes or cataracts, measurement errors and variations in measured values are minimized. be able to suppress it.

Also, in embodiments of the ophthalmic apparatus, the projection system may include a field lens (64) positioned between the deflection member and the diaphragm.

According to such a configuration, since the optical distance in the projection system can be shortened by arranging the field lens, it contributes to miniaturization of the size of the optical system (particularly the projection system) included in the ophthalmic apparatus. be able to

Further, in the ophthalmologic apparatus according to the embodiment, a diaphragm may be attached to the lens surface of the field lens.

Such a configuration simplifies the structure and contributes to further miniaturization of the optical system (particularly, the projection system) included in the ophthalmologic apparatus.

Further, in the ophthalmologic apparatus according to the embodiment, a diaphragm may be attached to the deflected light exit surface of the deflecting member.

Such a configuration simplifies the structure and contributes to further miniaturization of the optical system (particularly, the projection system) included in the ophthalmologic apparatus.

Further, in the ophthalmologic apparatus according to the embodiment, the diaphragm may be a ring diaphragm (65) having a ring-shaped translucent portion.

With such a configuration, it is possible to project a ring-shaped luminous flux having high brightness and a narrow (narrow width between the inner diameter and the outer diameter) onto the fundus of the eye. can be reduced, and a highly reliable eye refractive power value can be acquired while reducing the burden on the subject. In addition, since a thin ring-shaped luminous flux can also enter the pupil, even if the incident luminous flux is partially blocked by the opaque part of the lens due to eyelashes or cataracts, measurement errors and variations in measured values occur. can be suppressed.

Further, in the ophthalmologic apparatus according to the embodiment, the deflecting member may include a conical prism (63) that deflects light from the light source incident on the conical surface (63a) and emits the light from the bottom surface (63b).

With such a configuration, it is possible to reduce the cost and size of an ophthalmologic apparatus that acquires highly reliable eye refractive power values while reducing the burden on the subject.

Also, in an ophthalmic device according to an embodiment, the deflection member may comprise a ring lens (69).

With such a configuration, it is possible to reduce the cost and size of an ophthalmologic apparatus that acquires highly reliable eye refractive power values while reducing the burden on the subject.

<Modification>
The embodiment shown above is merely an example for carrying out the present invention. A person who intends to implement this invention can make arbitrary modifications, omissions, additions, etc. within the scope of the gist of this invention.

In the above-described embodiment, a transmissive liquid crystal panel is used as the optotype chart 43, but the configuration of the ophthalmologic apparatus according to the embodiment is not limited to this. The optotype chart 43 may be an optical chart.

1 Z alignment system 2 XY alignment system 3 Kerato measurement system 4 Target projection system 5 Anterior eye observation system 6, 6a Reflector measurement projection system 7 Reflector measurement light receiving system 9 Processing unit 63 Conical prism 64 Field lens 65 Ring diaphragm 69 Ring lens 110 control unit 111 main control unit 121 analysis unit 1000, 1000a ophthalmic apparatus

Claims (2)

An ophthalmic device for measuring the eye refractive power of an eye to be examined,
a projection system that projects light from a light source that can be arranged at a position substantially optically conjugate with the fundus of the eye to be inspected by moving in the direction of the optical axis, onto the eye to be inspected;
a light receiving system for receiving return light from the fundus of the light projected by the projection system;
an analysis unit that obtains an eye refractive power value of the eye to be examined based on the result of receiving the returned light by the light receiving system;
including
The projection system is
a diaphragm arranged at a position substantially conjugate optically with the pupil of the eye to be inspected, and having a predetermined pattern of light-transmitting portions formed thereon;
a conical prism disposed at a position substantially conjugate optically with the pupil, deflecting the light from the light source incident on the convex conical surface and emitting the light from the bottom surface to guide the light to the translucent portion;
a field lens arranged at a position substantially optically conjugate with the pupil between the conical prism and the diaphragm by attaching the diaphragm to the lens surface;
and projecting the light transmitted through the light-transmitting part onto the eye to be inspected;
ophthalmic equipment. The ophthalmologic apparatus according to claim 1 , wherein the aperture is a ring aperture in which the transparent portion is formed in a ring shape.

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