JP6837107B2 - Ophthalmic equipment - Google Patents

Description

The present invention relates to an ophthalmic apparatus.

Cataract is an eye disease in which visual acuity gradually deteriorates due to opacity of the crystalline lens, which plays the role of a lens. Cataract surgery is generally performed on optometry with advanced cataracts. For example, in cataract surgery, the cloudy crystalline lens is removed and an intraocular lens (IOL) is inserted in its place.

A glare test is known as a test for such cataracts. The glare test is a subjective test using a glare light source. The glare test can be an effective test for determining the timing of cataract surgery because the degree of impact on real life can be grasped by carrying out the test.

On the other hand, the glare test requires a response from the subject, so the test time is long. In addition, the glare test imposes a burden on the subject because glare light is incident on the eye to be inspected. Therefore, for example, by objectively inspecting whether or not the eye to be examined is a cataract eye and performing a glare examination only when necessary, unnecessary examination is eliminated and the burden on the subject is minimized. Is desirable.

Patent Document 1 discloses a method for objectively inspecting whether or not an eye to be inspected is a cataract eye based on the state of an image acquired by a refractometer.

Japanese Unexamined Patent Publication No. 2012-135528

However, since the reflex meter captures only the luminous flux transmitted through the predetermined ring zone in the pupil, it is difficult to detect the opacity in the region other than the ring zone (for example, the central portion and the outer peripheral portion of the crystalline lens). .. Further, in general, since the ring diameter is set to be small so that the measurement can be performed even with the eye to be inspected in the small pupil, it is difficult to detect the opacity that occurs in the outer peripheral portion at a relatively early stage.

Furthermore, some cataracts are determined by injecting a light beam from the pupil into the fundus of the eye and taking a transilluminated image for observing the opaque state of the crystalline lens using the reflected light from the fundus as a light source. It is difficult to confirm the opaque state over the entire crystalline lens by the reflected light of the lens. As described above, it is difficult to objectively and accurately examine whether or not the eye to be inspected is a cataract eye by the conventional method.

In addition to the glare test described above, the eye to be examined should be objectively and accurately measured before the measurement (examination), which takes a long time and imposes a burden on the subject, and the measurement should be performed only when necessary. Therefore, it is desirable to eliminate unnecessary measurements and minimize the burden on the subject.

The present invention has been made to solve such a problem, and an object thereof is an ophthalmic apparatus capable of selecting a measurement mode of an eye to be inspected based on a more accurate and objective measurement result. Is to provide.

The ophthalmic apparatus according to the embodiment includes an interference optical system, a first optical scanner, a second optical scanner, a control unit, and an analysis unit. The interfering optical system divides the light from the light source into reference light and measurement light, irradiates the eye to be inspected with the measurement light, generates interference light between the return light and the reference light, and detects the generated interference light. To do. The first optical scanner is arranged between the eye to be inspected and the interference optical system at a position substantially conjugate with the pupil of the eye to be inspected. The second optical scanner is arranged between the eye to be inspected and the interference optical system at a position substantially conjugate with the fundus of the eye to be inspected. The control unit controls at least the first optical scanner and the second optical scanner. The analysis unit controls at least one of the first optical scanner and the second optical scanner to deflect the measurement light, thereby causing interference corresponding to the detection result of the interference light obtained by the interference optical system at a plurality of positions of the eye to be inspected. Determine the type of cataract based on the signal intensity distribution. Control unit when the type of cataract Ri by the analysis unit determines, and a normal mode in which the inspection and cataract mode test to determine whether the subject's eye is cataract eye is performed is not performed selecting a cataract mode among the plurality of measurement modes of the eye, including.

According to the embodiment, it is possible to provide an ophthalmic apparatus capable of selecting a measurement mode of an eye to be inspected based on a more accurate and objective measurement result.

It is the schematic which shows the structural example of the ophthalmic apparatus which concerns on embodiment. It is the schematic which shows the structural example of the ophthalmic apparatus which concerns on embodiment. It is the schematic which shows the operation example of the ophthalmic apparatus which concerns on embodiment. It is the schematic which shows the operation example of the ophthalmic apparatus which concerns on embodiment. It is the schematic which shows the operation example of the ophthalmic apparatus which concerns on embodiment. It is the schematic which shows the operation example of the ophthalmic apparatus which concerns on embodiment. It is the schematic which shows the structural example of the ophthalmic apparatus which concerns on embodiment. It is the schematic which shows the structural example of the ophthalmic apparatus which concerns on embodiment. It is operation explanatory drawing of the ophthalmic apparatus which concerns on embodiment. It is operation explanatory drawing of the ophthalmic apparatus which concerns on embodiment. It is a flow figure which shows the operation example of the ophthalmic apparatus which concerns on embodiment.

An example of an embodiment of the ophthalmic apparatus 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 apparatus according to the embodiment is capable of performing objective measurement and subjective examination. Objective measurement is a measurement method for acquiring information about an eye to be examined mainly by using a physical method without referring to a response from the subject. 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. Objective measurement includes objective refraction measurement, corneal shape measurement, intraocular pressure measurement, fundus photography, optical interference measurement and the like.

On the other hand, the subjective test is a measurement method for acquiring information by using the response from the subject. 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.

The ophthalmic apparatus according to the embodiment is capable of performing at least one of any subjective tests and any objective measurements. Optical interference measurement is used to acquire eyeball information representing the structure of the eye to be inspected, such as axial length, corneal thickness, anterior chamber depth, and lens thickness. In addition, optical interference measurement can be used to acquire an image or analysis data of the eye to be inspected.

<Composition>
1 and 2 show a configuration example of the ophthalmic apparatus according to the embodiment. The ophthalmic apparatus 1000 has Z alignment system 1, XY alignment system 2, kerato measurement system 3, optotype projection system 4, observation system 5, reflex measurement projection system 6, and reflex as optical systems for inspecting the eye to be inspected E. The measurement light receiving system 7 and the intraocular distance measurement system 8 are included. In addition, the ophthalmic apparatus 1000 includes a processing unit 9.

(Processing unit 9)
The processing unit 9 controls each unit of the ophthalmic apparatus 1000. In addition, the processing unit 9 can execute various arithmetic processes. The processing unit 9 includes a processor. The functions of the processor are, 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)) , FPGA (Field Programmable Gate Array)) and the like. The processing unit 9 realizes the function according to the embodiment by reading and executing a program stored in a storage circuit or a storage device, for example.

(Observation system 5)
The observation system 5 captures a moving image of the anterior segment of the eye E to be inspected. The light (infrared light) from the anterior segment of the eye E to be inspected passes through the objective lens 51, passes through the dichroic mirrors 52 and 53, and passes through the aperture of the aperture 54. The light that has passed through the aperture 54 passes through the half mirror 55, passes through the relay lenses 56 and 57, and is imaged on the image pickup surface of the image pickup element 59 (area sensor) by the image pickup lens 58. The image sensor 59 performs image pickup and signal output at a predetermined rate. The output (video signal) of the image sensor 59 is input to the processing unit 9. The processing unit 9 displays the anterior segment image E'based on this video signal on the display screen 10a of the display unit 10. The anterior segment image E'is, for example, an infrared moving image. The observation system 5 may include an illumination light source for illuminating the anterior segment of the eye.

(Z alignment system 1)
The Z alignment system 1 irradiates the eye E to be inspected with light (infrared light) for aligning the observation system 5 in the optical axis direction (front-back direction, Z direction). The light output from the Z alignment light source 11 is applied to the cornea K of the eye E to be inspected, reflected by the cornea K, and imaged on the line sensor 13 by the imaging lens 12. When the position of the corneal apex changes in the anteroposterior direction, the projected position of light on the line sensor 13 changes. The processing unit 9 obtains the position of the corneal apex of the eye E to be inspected based on the projected position of light on the line sensor 13, and executes Z alignment based on this.

(XY alignment system 2)
The XY alignment system 2 irradiates the eye E with light (infrared light) for aligning in a direction orthogonal to the optical axis of the observation system 5 (horizontal direction (X direction), vertical direction (Y direction)). .. The XY alignment system 2 includes an XY alignment light source 21 provided in an optical path branched from the observation system 5 by a half mirror 55. The light output from the XY alignment light source 21 is reflected by the half mirror 55 and is irradiated to the eye E to be inspected through the observation system 5. The reflected light from the cornea K is guided to the image sensor 59 through the observation system 5.

This reflected light image (bright spot image) is included in the anterior segment image E'. As shown in FIG. 1, the processing unit 9 displays the anterior segment image E'including the bright spot image Br and the alignment mark AL on the display screen 10a. 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 9 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 3)
The kerato measurement system 3 projects a ring-shaped luminous flux (infrared light) for measuring the shape of the cornea K onto the cornea K. The kerato plate 31 is arranged between the objective lens 51 and the eye E to be inspected. A keratling light source 32 is provided on the back side (objective lens 51 side) of the kerato plate 31. By illuminating the kerato plate 31 with the light from the kerat ring light source 32, a ring-shaped luminous flux is projected onto the cornea K. The reflected light (keratling image) is detected by the image sensor 59 together with the anterior segment image. The processing unit 9 calculates the corneal shape parameter by performing a known calculation based on this keratling image.

(Optimal projection system 4)
The optotype projection system 4 presents various optotypes such as a fixation target and a target for subjective examination to the eye E to be inspected. The optotype projection system 4 includes a glare inspection optical system for projecting glare light onto the eye E to be inspected together with the above-mentioned optotype. The optical path of the glare inspection optical system is coupled to the optical path of the optotype projection system 4 by the half mirror 46.

The light (visible light) output from the light source 41 is applied to the optotype chart 42. The optotype chart 42 includes, for example, a transmissive liquid crystal panel and displays a pattern representing the optotype. The light transmitted through the optotype chart 42 passes through the half mirror 46, passes through the imaging lens 43 and the VCS lens 44, is reflected by the reflection mirror 45, is reflected by the dichroic mirror 53, and is transmitted through the dichroic mirror 52. It passes through the objective lens 51 and is projected onto the fundus Ef.

The glare light source 47 includes one or more visible light sources such as a white LED (Light Emitting Diode). The glare light output from the glare light source 47 is reflected by the half mirror 46 and is applied to the eye E to be inspected by the same path as the light output from the light source 41. As a result, glare light can be applied to the eye E to be inspected on which various optotypes are projected by the optotype projection system 4. The light source 41, the optotype chart 42, the half mirror 46, and the glare light source 47 can be integrally moved in the optical axis direction of the optotype projection system 4.

When performing the subjective examination, the processing unit 9 controls the optotype chart 42, the light source 41, and the VCS lens 44 based on the result of the objective measurement. The processing unit 9 displays the optotype selected by the examiner or the processing unit 9 on the optotype chart 42. As a result, the target is presented to the subject. The subject responds to the optotype. Upon receiving the input of the response content, the processing unit 9 further controls and calculates the subjective test value. For example, in the visual acuity measurement, the processing unit 9 selects and presents the next visual acuity based on the response to the Randold ring or the like, and repeatedly repeats this to determine the visual acuity value.

When performing a glare inspection, the processing unit 9 projects glare light from the glare light source 47 onto the eye E to be inspected together with the optotype according to the light source 41 and the optotype chart 42. The subject responds to the optotype while being irradiated with glare light. Upon receiving the input of the response content, the processing unit 9 further controls and calculates the subjective test value. For example, the processing unit 9 selects and presents the next optotype based on the response of the subject, and repeats this. As a result, it is inspected to what extent the optotype can be discriminated.

(Ref measurement projection system 6 and reflex measurement light receiving system 7)
The reflex measurement projection system 6 and the reflex measurement light receiving system 7 are used for objective refraction measurement (refraction measurement). The reflex measurement projection system 6 projects a ring-shaped luminous flux (infrared light) for objective measurement onto the fundus Ef. The reflex measurement light receiving system 7 receives the return light of the ring-shaped luminous flux from the eye E to be inspected.

The reflex measurement light source 61 is movable in the optical axis direction and is arranged at a position optically conjugate with the fundus Ef. The light output from the reflex measurement light source 61 passes through the condenser lens 62, is reflected by the reflection mirror 63, passes through the conical prism 64A and the relay lens 64B, and passes through the ring-shaped translucent portion of the ring diaphragm 64C. It becomes a morphological light source. The ring-shaped light flux formed by the ring diaphragm 64C is reflected by the reflecting surface of the perforated prism 65, passes through the rotary prism 66, and is guided to the quick return mirror 67.

The rotary prism 66 is used to average the light amount distribution of the ring-shaped luminous flux with respect to the blood vessels and the diseased part of the fundus Ef. Further, the quick return mirror 67 is used for switching between objective refraction measurement and intraocular distance measurement. When performing objective refraction measurement, the reflective surface of the quick return mirror 67 is arranged in an optical path (branched optical path) branched from the optical path of the observation system 5 by the dichroic mirror 52. As a result, both the optical path of the reflex measurement projection system 6 and the optical path of the reflex measurement light receiving system 7 are coupled to the optical path of the observation system 5. On the other hand, when measuring the intraocular distance, the quick return mirror 67 is retracted from this branched optical path. As a result, the optical path of the intraocular distance measurement system 8 is coupled to the optical path of the observation system 5.

In the objective refraction measurement, the ring-shaped light flux passing through the rotary prism 66 is reflected by the quick return mirror 67, reflected by the dichroic mirror 52, passed through the objective lens 51, and projected onto the fundus Ef.

The return light of the ring-shaped luminous flux projected on the fundus Ef passes through the objective lens 51 and is reflected by the dichroic mirror 52 and the quick return mirror 67. The return light reflected by the quick return mirror 67 passes through the rotary prism 66, passes through the hole portion of the perforated prism 65, passes through the relay lens 71 and the focusing lens 72, and is transmitted by the image pickup lens 73 to the image sensor 74. The image is formed on the imaging surface of the lens. The output of the image sensor 74 is input to the processing unit 9. The processing unit 9 calculates the spherical power S, the astigmatism power C, and the astigmatism axis angle A of the eye E to be inspected by performing a known calculation based on the output from the image sensor 74.

Based on the calculated refraction value, the processing unit 9 moves the reflex measurement light source 61 and the focusing lens 72 in the optical axis direction to positions where the reflex measurement light source 61, the fundus Ef, and the image sensor 74 are conjugate. Let me. Further, the processing unit 9 moves the focusing lens 85 (optical scanner 87b including the focusing lens 85) of the intraocular distance measurement system 8 in the optical axis direction in conjunction with the movement of the focusing lens 72 and the reflex measurement light source 61. Move. The processing unit 9 can integrally move the reflex measurement light source 61, the focusing lens 72, the focusing lens 85 (optical scanner 87b), the light source 41, and the optotype chart 42.

(Intraocular distance measurement system 8)
The intraocular distance measuring system 8 performs optical interference measurement for acquiring the intraocular distance as eyeball information. When the optical interference measurement is performed, the quick return mirror 67 is retracted from the branch optical path. Further, the ref measurement is performed before the optical interference measurement, and the position of the focusing lens 85 is adjusted so that the end face of the optical fiber 80a is conjugate with the fundus Ef.

As shown in FIG. 2, in the interferometer unit 80, the light (infrared light, broadband light) L0 output from the interferometer light source 81 is measured light LS and reference light by the fiber coupler 82 guided through the optical fiber 80b. It is divided into LR. The measurement light LS is guided to the collimator lens 84 through the optical fiber 80a. On the other hand, the reference optical LR is guided to the reference optical path length changing unit 90 through the optical fiber 80c.

The reference optical path length changing unit 90 changes the optical path length of the reference optical path LR. The reference light LR guided to the reference optical path length changing unit 90 is converted into a parallel luminous flux by the collimator lens 91 and incident on the beam splitter 92. The beam splitter 92 splits the reference light LR into two light fluxes (retina / anterior chamber depth light flux and corneal light flux) at a split ratio of 50:50. The splitting ratio of the beam splitter 92 does not necessarily have to be equal splitting, and may be a splitting ratio according to the configuration of the optical system and the like.

The retina / anterior chamber depth shutter 93 and the retina / anterior chamber depth reference mirror unit 94 are provided in the transmission direction of the beam splitter 92, and the corneal shutter 95 and the corneal reference mirror unit 96 are provided in the reflection direction. Has been done. The retinal / anterior chamber depth reference mirror unit 94 includes an imaging lens 94A and a retinal / anterior chamber depth reference mirror 94B. The corneal reference mirror unit 96 includes an imaging lens 96A and a corneal reference mirror 96B.

The shutter 93 for the depth of the retina / anterior chamber is inserted into the optical path of the light beam for the depth of the retina / anterior chamber (reference optical path for the depth of the retina / anterior chamber) between the beam splitter 92 and the reference mirror 94B for the depth of the retina / anterior chamber. It is possible to escape. The corneal shutter 95 is removable with respect to the optical path of the corneal luminous flux (corneal reference optical path) between the beam splitter 92 and the corneal reference mirror 96B. When the shutter 93 for the depth of the retina / anterior chamber is retracted from the optical path, the light beam for the depth of the retina / anterior chamber is imaged on the reflective surface of the reference mirror 94B for the depth of the retina / anterior chamber by the imaging lens 94A, and the retina / anterior chamber depth is formed. It is reflected by the reference mirror 94B for the depth of the anterior chamber, passes through the imaging lens 94A, and returns to the beam splitter 92. When the corneal shutter 95 is retracted from the optical path, the corneal light beam is imaged on the reflecting surface of the corneal reference mirror 96B by the imaging lens 96A, reflected by the corneal reference mirror 96B, and passes through the imaging lens 96A. Then, it returns to the beam splitter 92.

On the other hand, the measurement light LS output from the interferometer unit 80 is converted into a parallel luminous flux by the collimator lens 84. The crystalline lens 89 is inserted and removed from the optical path of the measurement light LS, which is a parallel luminous flux. When the crystalline lens 89 is inserted in the optical path, the measurement light LS as the parallel luminous flux is deflected by the optical scanners 87c and 87b, respectively, passes through the relay lens 86 and the crystalline lens 89, and is deflected by the mirror 87a. .. When the crystalline lens 89 is retracted from the optical path, the measurement light LS as a parallel light flux is deflected by the optical scanners 87c and 87bb, respectively, passes through the relay lens 86, and is deflected by the mirror 87a.

The measurement light LS deflected by the mirror 87a passes through the pupil lens 88, is reflected by the dichroic mirror 52, passes through the objective lens 51, and is irradiated to the eye E to be inspected. The return light of the measurement light LS from the eye E to be inspected passes through the objective lens 51 and is guided to the interferometer unit 80 through the same path as the outward path.

The optical scanner 87c is a deflection unit arranged at a position optically conjugate with the pupil of the eye E to be inspected. The optical scanner 87c is used for scanning the fundus Ef of the eye E to be inspected. The optical scanner 87c includes, for example, one or more galvanometer mirrors, and changes the deflection direction of the measurement light LS under the control of the processing unit 9. In FIG. 1, the optical scanner 87c includes mirrors 874, 873 that are rotatable in directions orthogonal to each other, for example, an intermediate position between the mirrors 874, 873 in the optical path of the measurement light LS is optical with the pupil of the eye E to be inspected. It is arranged so as to be in a mutually conjugate position.

The optical scanner 87b is a deflection unit arranged at a position optically conjugate with the fundus Ef of the eye E to be inspected. The optical scanner 87b is used for scanning the crystalline lens of the eye E to be inspected (intrapupil scan). The optical scanner 87b includes, for example, one or more galvanometer mirrors, and changes the deflection direction of the measurement light LS under the control of the processing unit 9. In FIG. 1, the optical scanner 87b includes mirrors 872, 871 that are rotatable in directions orthogonal to each other, and a focusing lens 85, for example, an intermediate position between the mirrors 872 and 871 in the optical path of the measurement light LS. It is arranged so as to be optically conjugate with the fundus Ef of the eye E to be inspected. The optical scanner 87b can move in the optical axis direction of the intraocular distance measuring system 8. For example, the intraocular distance measuring system 8 includes a moving mechanism for moving the optical scanner 87b in the optical axis direction, and a driving unit controlled by the processing unit 9 drives the moving mechanism.

The fiber coupler 82 interferes with the reference light that has passed through the reference optical path length changing unit 90 and the return light of the measurement light LS. The interference light LC generated thereby is guided to the spectroscope 83 by the optical fiber 80d. The spectroscope 83 spatially separates the wavelengths of the interference light LC, and detects these wavelength components with a line sensor. The processing unit 9 extracts information in the depth direction by performing known signal processing such as FFT (Fast Fourier Transform) on the signal output from the spectroscope 83.

In this example, spectral domain OCT (Optical Coherence Tomography) is applied, but other types of OCT can also be applied. For example, when swept source OCT is applied, a wavelength sweep light source (wavelength variable light source) is provided instead of the low coherence light source (interferometer light source 81), and photodetection of a balanced photodiode or the like is provided instead of the spectroscope 83. A vessel is provided.

The processing unit 9 can move the retina / anterior chamber depth reference mirror unit 94 and the corneal reference mirror unit 96 so that the interference signal is arranged at a predetermined position in the depth direction. An example of the change in the intensity of the interference signal obtained by the FFT in the depth direction is shown in FIG. In the state where the interference signal SC0 shown by the dotted line is obtained, the interference signal SC0 is within the predetermined range shown in FIG. 3 by bringing the retina / anterior chamber depth reference mirror unit 94 close to the beam splitter 92 as shown in FIG. Can be moved (corresponding to the retina). That is, by moving the imaging lens 94A and the reference mirror 94B for the depth of the retina / anterior chamber from the position indicated by the dotted line to the position indicated by the solid line, the interference signal SC0 can be moved within a desired range.

By utilizing the position of the corneal apex detected by using the Z alignment system 1, the distance (operating distance) of the objective lens 51 with respect to the eye E to be inspected can be kept constant. Here, when the corneal shutter 95 is retracted from the optical path, the interference signal corresponding to the cornea K is also detected by the spectroscope 83 at the same time. The corneal reference mirror 96B is arranged at a position separated from the cornea K by a predetermined distance d so as not to overlap the interference signal SC1 corresponding to the retina (FIG. 5). As a result, as shown in FIG. 6, both the interference signal SC1 corresponding to the retina and the interference signal SC2 corresponding to the cornea can be simultaneously acquired in the measurement range R in the depth direction.

As shown in FIG. 6, when the signal sensitivity SC changes in the measurement range R, the interference signal SC1 having a relatively weak signal is detected in the measurement range R1 having a relatively high sensitivity, and the interference signal SC2 having a relatively strong signal is detected relatively. It can be detected in the low-sensitivity measurement range R2. As a result, the detection accuracy of both interference signals is improved.

In this embodiment, when measuring the intraocular distance of the eye E to be inspected, the processing unit 9 moves the retina / anterior chamber depth reference mirror unit 94 with the corneal reference mirror unit 96 fixed. As a result, it becomes possible to measure various intraocular distances of the eye E to be inspected with reference to the apex of the cornea as a reference site. As shown in FIG. 5, when measuring the axial length, the distance between the apex of the cornea and the fundus (retina) is moved by moving the reference mirror unit 94 for the depth of the retina / anterior chamber so that the interference signal corresponding to the retina can be detected. Find D1. When measuring the anterior chamber depth, the distance D2 between the apex of the cornea and the anterior surface of the lens is obtained by moving the reference mirror unit 94 for the depth of the retina / anterior chamber so that the interference signal corresponding to the anterior chamber surface of the lens can be detected. When measuring the lens thickness, the distance (D2 + D3) between the apex of the cornea and the posterior surface of the lens is obtained by moving the reference mirror unit 94 for the depth of the retina / anterior chamber so that the interference signal corresponding to the posterior surface of the lens can be detected, and the distance (D2 + D3). ) By subtracting the above-mentioned distance D2 to obtain the distance D3. When measuring the corneal thickness, the interference signal corresponding to the posterior surface of the cornea is detected to obtain the distance between the apex of the cornea and the posterior surface of the cornea.

(Information processing system configuration)
The information processing system of the ophthalmic apparatus 1000 will be described. Examples of the functional configuration of the information processing system of the ophthalmic apparatus 1000 are shown in FIGS. 7 and 8. FIG. 7 shows an example of a functional block diagram of the information processing system of the ophthalmic apparatus 1000. FIG. 8 shows an example of a functional block diagram of the arithmetic processing unit 120 of FIG. 7. The processing unit 9 includes a control unit 110 and an arithmetic processing unit 120. Further, the ophthalmic apparatus 1000 includes a display unit 170, an operation unit 180, and a communication unit 190.

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

The main control unit 111 selects one of a plurality of predetermined measurement modes based on the analysis result by the analysis unit 130 described later, and measures each part of the ophthalmic apparatus 1000 according to the selected measurement mode. Control as. The plurality of measurement modes that can be selected by the main control unit 111 include at least a cataract mode in which the glare test is performed and a normal mode in which the glare test is not performed. Specifically, the main control unit 111 determines that the eye E to be inspected may be a cataract eye when the analysis result by the analysis unit 130 satisfies the above-mentioned predetermined condition, and selects the cataract mode.

The main control unit 111 performs various controls of the ophthalmic apparatus 1000 as a measurement control unit. The main control unit 111 controls the Z alignment light source 11 of the Z alignment system 1, the line sensor 13, the XY alignment light source 21 of the XY alignment system 2, and the keratling light source 32 of the kerato measurement system 3. As a result, the amount of light output from the Z alignment light source 11, the XY alignment light source 21, and the keratling light source 32 is changed, and lighting or non-lighting is switched. In addition, the 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 optotype projection system 4, the optotype chart 42, the VCS lens 44, and the glare light source 47. As a result, the amount of light output from the light source 41 and the glare light source 47 is changed, and lighting or non-lighting is switched. In addition, the display of the optotype and the fixation target on the optotype chart 42 can be turned on / off, and the optotype and the fixation target can be switched. For example, as shown in FIG. 10, glare lights G1 and G2 are emitted at positions horizontally separated from the optotype T1 by a predetermined distance. The positions of the light source 41, the optotype chart 42, and the glare light source 47 in the optical axis direction are changed. Further, the VCS lens 44 corrects the astigmatic state of the eye E to be inspected.

The main control unit 111 controls the image sensor 59 of the observation system 5. As a result, the signal acquired by the image sensor 59 is taken in, and the arithmetic processing unit 120 forms an image or the like. When the observation system 5 includes an illumination light source, the main control unit 111 can control the illumination light source.

The main control unit 111 controls the reflex measurement light source 61, the rotary prism 66, and the quick return mirror 67 of the reflex measurement projection system 6. As a result, the reflex measurement light source 61 is moved along the optical axis of the reflex measurement projection system 6, the amount of light output from the reflex measurement light source 61 is changed, and lighting or non-lighting is switched. Further, the rotary prism 66 is rotated, and the optical path is switched by the quick return mirror 67.

The main control unit 111 controls the focusing lens 72 and the image pickup device 74 of the reflex measurement light receiving system 7. As a result, the position of the focusing lens 72 in the optical axis direction is changed, the signal acquired by the image sensor 74 is taken in, and the arithmetic processing unit 120 forms an image or the like.

The main control unit 111 determines at least one of the amount of light output from the reflex measurement light source 61, the detection sensitivity of the image sensor 74, the exposure time, and the number of superposed images based on the light detected by the image sensor 74. It is possible to change. As a result, the measurement conditions of the reflex measurement projection system 6 and the reflex measurement light receiving system 7 are changed.

The main control unit 111 includes an interferometer light source 81, a spectroscope 83, a focusing lens 85, optical scanners 87b and 87c, a crystalline lens 89, a shutter for retinal / anterior chamber depth 93, a shutter for cornea 95, and a shutter for retinal / anterior chamber depth. It controls the reference mirror unit 94 and the reference mirror unit 96 for the cornea. As a result, the amount of light output from the interferometer light source 81 is changed, lighting or non-lighting is switched, the signal acquired by the spectroscope 83 is taken in, and the arithmetic processing unit 120 forms an image or the like. This is done, or the position of the focusing lens 85 in the optical axis direction is changed. Further, the incident position of the measurement light LS with respect to the eye E to be inspected is changed, and the position of the reference mirror is changed. The main control unit 111 may move the focusing lens 85 along the optical axis of the intraocular distance measuring system 8 in conjunction with the reflex measuring light source 61 and the focusing lens 72. Further, the main control unit 111 may further move the light source 41 and the optotype chart 42 along the optical axis in conjunction with the focusing lens 85. The main control unit 111 may move the focusing lens 85 in the optical axis direction independently of the optical scanner 87b, or the focusing lens 85 and the optical scanner 87b may be integrally moved in the optical axis direction. ..

The main control unit 111 exclusively controls the optical scanners 87b and 87c. As a result, it becomes possible to scan the crystalline lens with the measurement light deflected toward the desired portion of the fundus Ef of the eye to be inspected E and acquire information on a plurality of positions in the eye to be inspected E. The main control unit 111 can also control the optical scanners 87b and 87c in parallel.

The main control unit 111 changes at least one of the amount of light output from the interferometer light source 81, the detection sensitivity of the spectroscope 83, the exposure time, and the number of superposed images based on the light detected by the spectroscope 83. It is possible to do. As a result, the measurement conditions of the intraocular distance measurement system 8 are changed.

The crystalline lens 89 is an example of the “focus adjustment range changing means” provided corresponding to the measurement target. The "focus adjustment range changing means" moves the focusing adjustment range by the focusing lens to the vicinity of the measurement target in order to perform highly accurate focusing on the measurement target. Specifically, the amount of movement is insufficient only by moving the focusing lens 85 (optical scanner 87b), and the in-eye distance measuring system 8 cannot be focused on the front surface of the crystalline lens or the rear surface of the crystalline lens. Therefore, when measuring the intraocular distance with respect to the crystalline lens such as the front surface of the crystalline lens and the rear surface of the crystalline lens, the main control unit 111 inserts the crystalline lens lens 89 into the optical path of the measurement light LS. As a result, the focusing adjustment range of the focusing lens 85 can be moved to the vicinity of the crystalline lens, and the intraocular distance with respect to the crystalline lens can be measured with high accuracy while focusing on the front surface of the crystalline lens and the rear surface of the crystalline lens. ..

Further, the main control unit 111 performs a process of writing data to the storage unit 112 and a process of reading data from the storage unit 112.

The storage unit 112 stores various types of data. The data stored in the storage unit 112 includes, for example, an optical interference measurement result, an image data acquired by the optical interference measurement, an image data of a fundus image, an 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. The measurement information is stored in the storage unit 112 when the optical refractive power of the eye to be inspected E is measured inside or outside the ophthalmic apparatus 1000. In addition, various programs and data for operating the ophthalmic apparatus 1000 are stored in the storage unit 112.

(Calculation processing unit 120)
The arithmetic processing unit 120 analyzes, for example, the detection result of interference light, calculates the refractive power of the eye, calculates the intraocular distance (axial length, depth of anterior chamber, lens thickness, corneal thickness, etc.), calculates the IOL frequency, and calculates the light. It executes various operations such as generation of an interference measurement image (OCT image) and analysis of an optical interference measurement image. The arithmetic processing unit 120 includes an analysis unit 130, an optical power calculation unit 121, an intraocular distance calculation unit 122, and an IOL power calculation unit 123. The intraocular distance calculation unit 122 includes an axial length calculation unit 122A, an anterior chamber depth calculation unit 122B, a crystalline lens thickness calculation unit 122C, and a corneal thickness calculation unit 122D.

The analysis unit 130 analyzes the intensity of the interference signal based on the interference light detected by the intraocular distance measurement system 8 or its distribution. In a cataract eye, the signal intensity or its distribution based on the interference light between the return light from the fundus Ef and the reference light of the measurement light incident on the pupil of the eye E to be inspected changes. The analysis unit 130 analyzes a change in the intensity or distribution of the plurality of interference signals acquired by detecting a plurality of interference lights based on the return light of the measurement light applied to the plurality of positions of the eye E to be inspected.

The types of cataracts are roughly classified into three types, "nuclear cataracts", "subcapsular cataracts", and "cortical cataracts", depending on the opaque part of the crystalline lens. In "nuclear cataract", opacity occurs in the central part of the crystalline lens. "Subcapsular cataract" includes "posterior subcapsular cataract" in which opacity occurs on the posterior end side of the central part of the crystalline lens and "anterior subcapsular cataract" in which opacity occurs on the anterior end side. In "cortical cataract", opacity occurs on the outer periphery of the crystalline lens. In the case of "nuclear cataract" or "subcapsular cataract", the signal intensity based on the return light of the measurement light passing through the central part of the crystalline lens is extremely small as compared with the healthy eye.

The analysis unit 130 compares the intensity of the interference signal acquired from the detection result of the interference light based on the return light of the measurement light deflected by the optical scanner 87b so as to pass through the central portion of the crystalline lens with the first threshold value. As a result, the main control unit 111 can determine that the eye E to be inspected may have "nuclear cataract" or "subcapsular cataract" when the intensity is equal to or less than the first threshold value (when a predetermined condition is satisfied). it can.

In the case of "cortical cataract", it is difficult to determine whether or not the signal intensity based on the return light of the measurement light that has passed through the central part of the crystalline lens has decreased compared to that of a healthy eye, but the measurement that has passed through the outer peripheral part of the crystalline lens. The signal intensity based on the return light of light becomes smaller.

FIG. 9 schematically shows an example of the intensity distribution of the interference signal with respect to the eye to be inspected for “cortical cataract”. FIG. 9 shows an example of the intensity distribution of the interference signal of a predetermined scan line in the crystalline lens of the eye to be inspected where the line scan was performed. The vertical axis shows the signal strength of the interference signal detected in the scan line, and the horizontal axis shows the scan position in the scan line. The vicinity of both ends of the scan position corresponds to the outer peripheral portion of the crystalline lens. As shown in FIG. 9, the intensity distribution W2 of the interference signal in the eye to be inspected for "cortical cataract" has a lower intensity than the central portion of the crystalline lens in the outer peripheral portion with respect to the intensity distribution W1 of the interference signal in the healthy eye.

The analysis unit 130 analyzes the intensity distribution of the interference signal acquired from the detection result of the interference light based on the return light of the measurement light deflected by the optical scanner 87b so as to pass through the outer peripheral portion of the crystalline lens. For example, the analysis unit 130 identifies an interference signal in the outer peripheral portion of the crystalline lens, compares the difference between the intensity distribution W1 and the intensity distribution W2 and the second threshold value in the central portion of the crystalline lens, and compares the second threshold value with the intensity distribution W2 in the outer peripheral portion of the crystalline lens. The strength of the interference signal of is compared with the third threshold value. As a result, when the difference is equal to or less than the second threshold value and the intensity is equal to or less than the third threshold value (when a predetermined condition is satisfied), the main control unit 111 may have "cortical cataract" in the eye E to be inspected. It can be determined that there is.

As described above, the main control unit 111 selects the measurement mode based on the analysis result by the analysis unit 130, and controls each unit of the ophthalmic apparatus 1000 according to the selected measurement mode.

In the calculation of the optical power, the eye refractive power calculation unit 121 analyzes the shape of the output (ring image) from the reflex measurement light receiving system 7. For example, the eye refractive power calculation unit 121 obtains the position of the center of gravity of the ring image from the brightness distribution in the obtained image, obtains the brightness distribution along a plurality of scanning directions radially extending from the position of the center of gravity, and obtains the brightness distribution along a plurality of scanning directions extending radially from the center of gravity position. Identify the image. Subsequently, the eye refractive power calculation unit 121 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. Alternatively, the eye refractive power calculation unit 121 can obtain the parameter of the eye refractive power based on the deformation and displacement of the ring image with respect to the reference pattern.

The optical power calculation unit 121 can obtain at least the spherical power from the result of the optical interference measurement using the intraocular distance measurement system 8. For example, the eye refractive power calculation unit 121 identifies the position of the focusing lens 85 at which the detection signal of the interference light LC peaks due to the movement of the focusing lens 85, and identifies the position of the focusing lens corresponding to 0D. The equivalent spherical power is obtained based on the position of the focusing lens 85 that becomes the peak.

The eye refractive power calculation unit 121 calculates the corneal refractive power, the corneal astigmatism degree, and the corneal astigmatism axis angle based on the keratling image acquired by the observation system 5. For example, the optical power calculation unit 121 calculates the radius of curvature of the cornea of the strong main meridian and the weak main meridian of the anterior surface of the cornea by analyzing the keratling image, and calculates the above parameters based on the radius of curvature of the cornea.

The intraocular distance calculation unit 122 calculates one or more intraocular distances of the eye E to be inspected based on the detection data of the two interference lights acquired by the intraocular distance measurement system 8. The intraocular distance calculation unit 122 calculates the intraocular distance of the eye E to be inspected based on the distance between the positions of the two interference signals (see, for example, FIG. 6) based on the two interference lights included in the detection data. The intraocular distance calculation unit 122 can calculate a plurality of intraocular distances of the eye E to be inspected while inserting and removing the crystalline lens 89. The intraocular distance calculation unit 122 calculates the axial length and the corneal thickness (first intraocular distance) based on the detection data acquired in the state where the crystalline lens 89 is retracted from the optical path. In addition, the intraocular distance calculation unit 122 calculates the anterior chamber depth and the crystalline lens thickness (second intraocular distance) based on the detection data acquired with the crystalline lens 89 inserted in the optical path. The crystalline lens has a focal length in combination with an existing lens (for example, a relay lens 86), which may be replaceable with the relay lens 86.

The intraocular distance calculation unit 122 can calculate a plurality of intraocular distances based on the reference site of the eye E to be inspected. Examples of the reference portion include a portion where the intensity of the return light of the measurement light LS from the eye E to be inspected is strong. Reference sites include the apex of the cornea (anterior surface of the cornea) of the eye E to be inspected, the retina, the internal limiting membrane, and the like. As a result, even if the eye E to be inspected moves and the position of the interference signal changes, by using the interference signal at the reference site as a reference, it is possible to always calculate a plurality of intraocular distances with high accuracy. ..

The axial length calculation unit 122A obtains the axial length (intraocular distance D1) based on the distance between the position of the interference signal corresponding to the apex of the cornea and the position of the interference signal corresponding to the retina and the amount of movement of the reference mirror unit. .. The anterior chamber depth calculation unit 122B determines the anterior chamber depth (intraocular distance D2) based on the distance between the position of the interference signal corresponding to the apex of the cornea and the position of the interference signal corresponding to the anterior surface of the crystalline lens and the amount of movement of the reference mirror unit. Ask. The crystalline lens thickness calculation unit 122C obtains a distance (D2 + D3) based on the distance between the position of the interference signal corresponding to the apex of the cornea and the position of the interference signal corresponding to the posterior surface of the crystalline lens, and calculates the distance D2 from the obtained distance (D2 + D3). The lens thickness (distance D3) is obtained by subtracting it. The corneal film thickness calculation unit 122D obtains the corneal film thickness based on the distance between the position of the interference signal corresponding to the apex of the cornea (front surface of the cornea) and the position of the interference signal corresponding to the posterior surface of the cornea.

In the calculation of the IOL frequency, the IOL frequency calculation unit 123 uses a known calculation formula for at least one of the measurement result of the kerato and the axial length, the anterior chamber depth, the crystalline lens thickness, and the corneal thickness obtained by the intraocular distance calculation unit 122. The IOL frequency is obtained by substituting into. The IOL power calculation unit 123 may obtain the IOL power by substituting the calculation result of the optical power and the calculation result of the axial length into a known calculation formula.

(Display unit 170, operation unit 180)
The display unit 170 displays information under the control of the control unit 110. The display unit 170 includes a display unit 10. The operation unit 180 is used for operating the ophthalmic apparatus 1000 and inputting information. The operation unit 180 includes various hardware keys (joysticks, 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 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 1000. 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 interferometer unit 80 is an example of the “interferometry optical system” according to the embodiment. The interferometer light source 81 is an example of the "light source" according to the embodiment. The optical scanner 87b is an example of the “irradiation position changing unit” and the “deflecting unit” according to the embodiment.

<Operation example>
The operation of the ophthalmic apparatus 1000 according to the embodiment will be described. An example of the operation of the ophthalmic apparatus 1000 is shown in FIG. FIG. 11 shows a flow chart of an operation example of the ophthalmic apparatus 1000.

(S1)
When the examiner performs a predetermined operation on the operation unit 180, the measurement items by the ophthalmic apparatus 1000 are set. The measurement mode of the ophthalmic apparatus 1000 is determined according to the measurement items set in S1.

(S2)
When the examiner performs a predetermined operation on the operation unit 180 with the subject's face fixed to the face receiving portion (not shown), the ophthalmic apparatus 1000 is fixed by the light source 41 and the optotype chart 42. The target is projected onto the eye E to be inspected and alignment is performed. Specifically, the main control unit 111 lights the Z alignment light source 11, the XY alignment light source 21, and the light source 41. The processing unit 9 acquires an imaging signal of the anterior segment image formed on the imaging surface of the imaging element 59, and displays the anterior segment image E'on the display unit 170 (display screen 10a of the display unit 10). .. After that, the optical system shown in FIG. 1 is moved to the examination position of the eye E to be inspected. The examination position is a position where the examination of the eye E to be inspected can be performed. The eye E to be inspected is placed at the examination position through the above-mentioned alignment (alignment by the Z alignment system 1, the XY alignment system 2, and the observation system 5). The movement of the optical system is executed by the main control unit 111 according to an operation or instruction by the user or an instruction by the main control unit 111. That is, the movement of the optical system to the examination position of the eye E to be inspected and the preparation for performing the objective measurement are performed.

Further, the main control unit 111 links the reflex measurement light source 61 with the focusing lens 72, the focusing lens 85, the light source 41, and the optotype chart 42 to move the reflex measurement light source 61 to the origin, for example, the position of 0D along the optical axis. ..

The main control unit 111 projects the fixation target onto the eye E to be inspected by the light source 41 and the target chart 42, and causes the kerato measurement to be executed. That is, the main control unit 111 turns on the keratling light source 32. When light is output from the keratling light source 32, a ring-shaped luminous flux for measuring the shape of the cornea is projected onto the cornea K. The eye refractive power calculation unit 121 calculates the radius of curvature of the cornea by performing arithmetic processing on the image acquired by the image pickup element 59, and the corneal refractive power, the degree of corneal astigmatism, and the corneal astigmatism are calculated from the calculated radius of curvature of the cornea. Calculate the axis angle. In the control unit 110, the calculated corneal refractive power and the like are stored in the storage unit 112. The operation of the ophthalmic apparatus 1000 shifts to S3 by the instruction from the main control unit 111 or the user's operation or instruction to the operation unit 180.

(S3)
The main control unit 111 arranges the reflecting surface of the quick return mirror 67 in the optical path branched from the optical path of the observation system 5 by the dichroic mirror 52. The main control unit 111 projects the fixation target onto the eye E to be inspected by the light source 41 and the optotype chart 42, and causes the ref measurement to be executed. That is, the main control unit 111 projects the ring-shaped measurement pattern luminous flux for the reflex measurement onto the eye E to be inspected as described above. A ring image based on the return light of the measurement pattern luminous flux from the eye E to be inspected is formed on the image plane of the image sensor 74. The main control unit 111 determines whether or not a ring image based on the return light from the fundus Ef detected by the image sensor 74 could be 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 image sensor 74, 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. It is determined whether or not the ring image can be obtained by determining whether or not the ring can be formed based on a point (image) whose intensity is equal to or higher than a predetermined height.

When it is determined that the ring image can be obtained, the eye refractive power calculation unit 121 analyzes the ring image based on the return light of the measurement pattern luminous flux projected on the eye E to be inspected by a known method, and analyzes the temporary spherical power S and the tentative spherical power S. Acquire the astigmatic power C. Based on the temporary spherical power S and astigmatic power C, the reflex measurement light source 61, the focusing lens 72 (focusing lens 85), the light source 41 and the optotype chart 42 are placed at the equivalent spherical power (S + C / 2) position (provisional distance). Move to point position). From that position, after the landscape chart was viewed as astigmatism (that is, moved to the cloud fog position), a ring image was acquired again as the main measurement, and the analysis result of the ring image obtained in the same manner as described above and the focusing lens The spherical power S, the astigmatism power C, and the astigmatism axis angle A are obtained from the amount of movement. The optical power calculation unit 121 obtains the far point position of the eye to be inspected E (the far point position obtained by this measurement) from the obtained spherical power S and the astigmatic power C, and the light source 41 and the light source 41 and the obtained far point position are located at the obtained far point position. The optotype chart 42 is moved. In the control unit 110, the position of the focusing lens 72 (focusing lens 85), the calculated spherical power, and the like are stored in the storage unit 112. The operation of the ophthalmic apparatus 1000 shifts to S4 by the instruction from the main control unit 111 or the user's operation or instruction to the operation unit 180.

When it is determined that the ring image cannot be obtained, first, in consideration of the possibility of an abnormally intense refraction eye, the reflex measurement light source 61 and the focusing lens 72 are set in preset steps to the minus power side (for example, -10D) and the plus power. Move to the side (for example, + 10D) and detect the ring image at each position. When it is still determined that the ring image cannot be obtained, the operation of the ophthalmic apparatus 1000 shifts to S4. In the control unit 110, information indicating that the reflex measurement result was not obtained is stored in the storage unit 112.

(S4)
The main control unit 111 determines whether or not to execute the cataract check. In the cataract check, it is determined whether or not the eye E to be inspected is a cataract eye as described above. The main control unit 111 may determine whether or not to execute the cataract check based on the preset age of the subject (for example, whether or not the subject is 50 years or older) or the information set in S1. It is possible. When it is determined that the cataract check is to be executed (S4: Y), the operation of the ophthalmic apparatus 1000 shifts to S5. When it is determined that the cataract check is not executed (S4: N), the operation of the ophthalmic apparatus 1000 shifts to S10.

(S5)
When it is determined to execute the cataract check (S4: Y), the main control unit 111 executes the crystalline lens scan. The main control unit 111 retracts the reflective surface of the quick return mirror 67 from the optical path branched from the optical path of the observation system 5 by the dichroic mirror 52, and opens the optical interference measurement path (optical path of the intraocular distance measurement system 8). ..

Subsequently, the main control unit 111 controls the optical scanner 87b at each irradiation position while changing the irradiation position of the measurement light within a predetermined region in the fundus Ef of the eye E to be inspected, for example, by controlling the optical scanner 87c. By doing so, the crystalline lens of the eye E to be inspected is scanned. As a result, the detection results of the plurality of interference lights obtained by the intraocular distance measurement system 8 at the plurality of positions of the eye E to be inspected are acquired. The analysis unit 130 analyzes each of these plurality of positions as described above. The main control unit 111 determines whether or not the eye E to be inspected may be a cataract eye based on the analysis results by the analysis unit 130 for these plurality of positions.

Alternatively, the main control unit 111 determines whether or not the eye to be inspected E is a cataract eye with respect to the central portion of the crystalline body of the eye to be inspected E, and if it is determined that the eye to be inspected is not a cataract eye, the outer peripheral portion of the eye to be inspected E is covered. It may be determined whether or not the optometry E is a cataract eye. That is, as described above, it is determined whether or not the eye E to be examined has the possibility of "nuclear cataract" or "subcapsular cataract", and when it is determined that there is no possibility of either of them, the eye E to be examined is "cortical cataract". It may be determined whether or not there is a possibility of. As a result, the analysis unit 130 may determine that the eye E to be inspected may be a cataract eye based on the detection results of the plurality of interference lights obtained by the intraocular distance measurement system 8 at the plurality of positions of the eye E to be inspected. It is possible to determine whether or not.

(S6)
When it is determined that the eye E to be inspected may have cataract (S6: Y), the main control unit 111 selects the cataract mode as the measurement mode of the ophthalmic apparatus 1000. The operation of the ophthalmic apparatus 1000 shifts to S7. When it is determined that the eye E to be inspected is unlikely to have cataract (S6: N), the operation of the ophthalmic apparatus 1000 ends (end).

In addition, between S5 and S6, it was determined whether or not to execute the subjective examination based on the information set in S1, and when it was determined to execute the subjective examination, the ophthalmic apparatus 1000 was made to execute the subjective examination. It may be transferred to S6 later. At this time, when it is determined that the subjective test is not performed, the operation of the ophthalmic apparatus 1000 is shifted to S8 when the IOL prescription is performed, and the operation of the ophthalmic apparatus 1000 is terminated when the IOL prescription is not performed.

(S7)
When it is determined that the eye E to be inspected may have cataract (S6: Y), the main control unit 111 causes the glare test to be executed. The main control unit 111 projects the glare light from the glare light source 47 onto the eye E to be inspected together with the optotype according to the light source 41 and the optotype chart 42 (see FIG. 10). The subject responds to the optotype while the subject's eye is irradiated with glare light. Upon receiving the input of the response content, the processing unit 9 further controls and calculates the subjective test value. For example, the processing unit 9 selects and presents the next optotype based on the response of the subject, and repeats this. As a result, it is inspected to what extent the optotype can be discriminated.

(S8)
Next, the main control unit 111 retracts the reflective surface of the quick return mirror 67 from the optical path branched from the optical path of the observation system 5 by the dichroic mirror 52, and causes the intraocular distance measurement to be executed. In the intraocular distance measurement, at least one of axial length measurement, anterior chamber depth measurement, lens thickness measurement and corneal thickness measurement is performed.

<Measurement of axial length>
The main control unit 111 turns on the interferometer light source 81, and projects a bright spot onto the eye E to be inspected as a fixation target by the light source 41 and the optotype chart 42. Next, the main control unit 111 inserts the corneal shutter 95 into the corneal reference optical path, and retracts the retina / anterior chamber depth shutter 93 from the retina / anterior chamber depth reference optical path. After that, the main control unit 111 retracts the reflecting surface of the quick return mirror 67 from the optical path branched from the optical path of the observation system 5 by the dichroic mirror 52. As a result, an optical path of the measurement light LS is formed between the interferometer unit 80 and the eye E to be inspected, and the optical interference measurement path is opened.

The main control unit 111 determines whether or not there is a reflex measurement result based on the information stored in the storage unit 112 in S3.

When it is determined that there is a reflex measurement result, the main control unit 111 determines that the focusing lens 85 at the time of measuring the axial length from the position of the focusing lens 72 (focusing lens 85) stored in the storage unit 112 in S3. The position is determined, and the focusing lens 85 is moved to the determined position. Specifically, since the reflex measurement is performed in a cloud-fog state, the reflex measurement is moved by a predetermined distance ΔD from the position of the focusing lens 72 obtained in focusing on the eye E to be inspected. When the moving part of the reflex measurement system (ref measurement light source 61, focusing lens 72) and the focusing lens 85 of the intraocular distance measurement system 8 can be moved together, the focusing lens 85 is already in the cloud fog position at the time of reflex measurement in S3. Since it is located in, only the cloud fog should be returned.

Next, the main control unit 111 moves the retina / anterior chamber depth reference mirror unit 94 so that the position of the interference signal corresponding to the retina becomes a predetermined position.

On the other hand, when it is determined that there is no retina measurement result, the main control unit 111 moves the retina / anterior chamber depth reference mirror unit 94 so that the position of the interference signal corresponding to the retina becomes a predetermined position. Next, the main control unit 111 moves the focusing lens 85 so that the intensity of the interference signal corresponding to the retina is the highest.

As described above, when there is a reflex measurement result (that is, when the position of the focusing lens 85 is known), the interference signal corresponding to the retina can be easily detected by first setting the focusing state. .. On the other hand, when there is no reflex measurement result (that is, when the position of the focusing lens 85 is unknown), the interference signal corresponding to the retina is first detected to enable focusing on the retina. ..

Next, the main control unit 111 retracts the corneal shutter 95 from the corneal reference optical path. As a result, it becomes possible to simultaneously detect the interference signal corresponding to the apex of the cornea and the interference signal corresponding to the retina (see FIG. 6).

The axial length calculation unit 122A calculates the axial length based on the distance between the position of the interference signal corresponding to the apex of the cornea and the position of the interference signal corresponding to the retina, which can be detected at the same time. As described above, the axial length is used by using the distance between the positions of the two interference signals included in the detection data acquired in the state of focusing on the retina instead of the corneal apex where the reflection intensity of the return light of the measurement light LS is strong. Is required. As a result, it becomes possible to obtain the axial length with high accuracy.

<Measurement of anterior chamber depth>
The anterior chamber depth measurement is also performed according to the same flow as the axial length measurement.

In the anterior chamber depth measurement, first, the reflection surface of the quick return mirror 67 is retracted from the optical path branched from the optical path of the observation system 5 by the dichroic mirror 52, and the optical interference measurement path is opened. After that, the main control unit 111 inserts the crystalline lens 89 into the optical path (optical interference measurement path) of the measurement light LS. When the crystalline lens 89 is inserted, the position of the focusing lens moves to a predetermined position. As a result, the focusing adjustment range of the focusing lens 85 moves from the vicinity of the retina (fundus) to the vicinity of the crystalline lens. Next, the main control unit 111 moves the retina / anterior chamber depth reference mirror unit 94 so that the position of the interference signal corresponding to the front surface of the crystalline lens becomes a predetermined position, and the intensity of the interference signal corresponding to the front surface of the crystalline lens is increased. The focusing lens 85 is moved so as to be the highest.

After that, the main control unit 111 retracts both the retinal / anterior chamber depth shutter 93 and the corneal shutter 95 from their respective optical paths. As a result, it becomes possible to simultaneously detect the interference signal corresponding to the apex of the cornea and the interference signal corresponding to the anterior surface of the crystalline lens. The anterior chamber depth calculation unit 122B calculates the anterior chamber depth based on the distance between the position of the interference signal corresponding to the apex of the cornea and the position of the interference signal corresponding to the anterior surface of the crystalline lens, which can be detected at the same time.

As described above, the positions of the two interference signals included in the detection data acquired in the state where the focusing adjustment range by moving the focusing lens 85 is moved to the vicinity of the crystalline lens and focused on the front surface of the crystalline lens instead of the apex of the cornea. The depth of the anterior chamber is determined using the interval of.

<Measurement of lens thickness>
The lens thickness measurement is also performed according to the same flow as the axial length measurement.

In the lens thickness measurement, first, the reflection surface of the quick return mirror 67 is retracted from the optical path branched from the optical path of the observation system 5 by the dichroic mirror 52, and the optical interference measurement path is opened. After that, the main control unit 111 inserts the crystalline lens 89 into the optical path (optical interference measurement path) of the measurement light LS. Next, the main control unit 111 moves the retina / anterior chamber depth reference mirror unit 94 so that the position of the interference signal corresponding to the rear surface of the crystalline lens becomes a predetermined position, and the intensity of the interference signal corresponding to the rear surface of the crystalline lens is increased. The focusing lens 85 is moved so as to be the highest.

After that, the main control unit 111 retracts both the retinal / anterior chamber depth shutter 93 and the corneal shutter 95 from their respective optical paths. As a result, it becomes possible to simultaneously detect the interference signal corresponding to the apex of the cornea and the interference signal corresponding to the posterior surface of the crystalline lens. The crystalline lens thickness calculation unit 122C obtains the distance between the corneal apex and the posterior surface of the crystalline lens based on the distance between the position of the interference signal corresponding to the apex of the cornea and the position of the interference signal corresponding to the posterior surface of the crystalline lens, which can be detected at the same time. The crystalline lens thickness calculation unit 122C calculates the crystalline lens thickness by subtracting the anterior chamber depth obtained as described above from the distance between the obtained corneal apex and the posterior surface of the crystalline lens.

As described above, the positions of the two interference signals included in the detection data acquired in the state where the focusing adjustment range by moving the focusing lens 85 is moved to the vicinity of the crystalline lens and focused on the posterior surface of the crystalline lens instead of the apex of the cornea. The lens thickness can be determined using the interval of.

<Corneal thickness measurement>
In the corneal thickness measurement, the main control unit 111 turns on the interferometer light source 81 and projects the bright spot on the eye E to be inspected as a fixation target by the light source 41 and the optotype chart 42. Next, the main control unit 111 retracts the corneal shutter 95 from the corneal reference optical path, and inserts the retina / anterior chamber depth shutter 93 into the retina / anterior chamber depth reference optical path. After that, the main control unit 111 retracts the reflecting surface of the quick return mirror 67 from the optical path branched from the optical path of the observation system 5 by the dichroic mirror 52. As a result, the optical interference measurement path is opened.

The main control unit 111 retracts the crystalline lens 89 from the optical path of the measurement light LS, and moves the focusing lens 85 so that the intensity of the interference signal corresponding to the posterior surface of the cornea is highest. Since the interference signal corresponding to the apex of the cornea and the interference signal corresponding to the posterior surface of the cornea can be detected at the same time, the corneal thickness calculation unit 122D can detect the position of the interference signal corresponding to the apex of the cornea and the interference corresponding to the posterior surface of the cornea. The corneal thickness is calculated based on the distance from the signal position. As described above, the corneal film thickness is obtained by using the distance between the positions of the two interference signals included in the detection data acquired in the state of focusing on the posterior surface of the cornea instead of the apex of the cornea.

(S9)
The IOL power calculation unit 123 obtains the IOL power using at least one of the corneal refractive power (kerato value) obtained in S2, the axial length measurement, the anterior chamber depth, the crystalline lens thickness, and the corneal thickness. In the control unit 110, the obtained IOL frequency is stored in the storage unit 112. After that, the operation of the ophthalmic apparatus 1000 ends (end).

(S10)
When it is determined not to execute the cataract check (S4: N), the main control unit 111 determines whether or not to execute the subjective test based on the information set in S1. When it is determined that the subjective examination is to be performed (S10: Y), the operation of the ophthalmic apparatus 1000 shifts to S11. When it is determined not to perform the subjective test (S10: N), the operation of the ophthalmic apparatus 1000 ends (end).

(S11)
When it is determined to execute the subjective test (S10: Y), the main control unit 111 causes the subjective test to be executed. In the subjective test, the main control unit 111 displays a desired optotype by controlling the optotype chart 42, for example, based on a user's instruction to the operation unit 180. Further, the main control unit 111 moves the light source 41 and the optotype chart 42 to positions according to the result of the objective measurement. The subject responds to the optotype projected on the fundus Ef. For example, in the case of a visual acuity measurement target, the visual acuity value of the eye to be examined 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 110.

Alternatively, the main control unit 111 controls the VCS lens 44 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. The subject responds to the optotype projected on the fundus Ef. It is also possible to control the VCS lens based on the subject's response. For example, in the case of a visual acuity measurement target, the visual acuity value of the eye to be examined 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 110. The examiner or the control unit 110 determines the visual acuity value or the prescription value (S, C, A) based on the response from the examinee, and the operation of the ophthalmic apparatus 1000 ends (end).

<Modified example of the embodiment>
In the above-described embodiment, the case where the scanning position of the eye E to be inspected in the crystalline lens is changed by controlling the optical scanner 87b has been described, but the configuration of the ophthalmic apparatus according to the embodiment is not limited to this. For example, the scan position of the eye E to be inspected in the crystalline lens may be changed by translating the optical path of the measurement light toward the eye E to be inspected.

In this case, the ophthalmic apparatus 1000 includes a measuring head and a moving mechanism for moving the measuring head in the direction of the optical axis of the observation system 5 and in the direction orthogonal to the optical axis. The measurement head includes a Z alignment system 1, an XY alignment system 2, a kerato measurement system 3, an optotype projection system 4, an observation system 5, a reflex measurement projection system 6, a reflex measurement light receiving system 7, and an intraocular distance shown in FIG. The measurement system 8 is housed. The moving mechanism moves the measuring head under the control of the main control unit 111. As a result, it becomes possible to detect interference light based on the return light of the measurement light passing through an arbitrary part of the crystalline lens of the eye E to be inspected, and the eye E to be inspected may be a cataract eye as in the embodiment. It becomes possible to determine whether or not.

Further, in the above-described embodiment, the case where the optical scanner 87b is provided separately from the optical scanner 87c arranged at a position optically conjugate with the pupil of the eye to be inspected has been described. It is not limited to this. For example, the focusing lens 85 may be provided instead of the optical scanner 87b so that the optical scanner 87c can scan the crystalline lens of the eye E to be inspected by moving other optical members or inserting and removing the optical element.

[Action / Effect]
The operation and effect of the ophthalmic apparatus 1000 according to the embodiment will be described.

The ophthalmic apparatus (ophthalmic apparatus 1000) according to the embodiment includes an interferometric optical system (interferometer unit 80), an irradiation position changing unit (optical scanner 87b or moving mechanism), and a control unit (control unit 110 or main control unit 111). And include. The interference optical system divides the light (light L0) from the light source (interferometer light source 81) into a reference light (reference light LR) and a measurement light (measurement light LS), and divides the measurement light into an eye to be inspected (eye to be inspected E). Is irradiated to generate interference light (interference light LC) between the return light and the reference light, and the generated interference light is detected. The irradiation position changing unit is used to irradiate a plurality of positions of the eye to be inspected with measurement light. The control unit selects the measurement mode of the eye to be inspected based on the detection results of the plurality of interference lights obtained by the interference optical system at the plurality of positions.

According to such a configuration, the state of the eye to be inspected can be objectively and accurately measured (inspected) based on the detection results of a plurality of interference lights obtained by the interference optical system at a plurality of positions of the eye to be inspected. it can. As a result, it becomes possible to select the measurement mode of the eye to be inspected based on the objectively accurate measurement result. Therefore, it is possible to eliminate unnecessary measurement by objectively and accurately measuring the eye to be inspected before the measurement (examination), which takes a long time and imposes a burden on the subject, and performs the measurement only when necessary. It becomes possible to minimize the burden on the subject.

Further, in the ophthalmic apparatus according to the embodiment, the control unit may select the cataract mode when the detection result satisfies a predetermined condition.

According to such a configuration, it is determined whether or not the eye to be inspected is a cataract eye based on the detection results of a plurality of interfering lights obtained by the interference optical system at a plurality of positions of the eye to be inspected, and the determination result is used. The cataract mode can be selected based on. As a result, the eye to be examined is objectively and accurately measured before the cataract examination, and the examination is performed only when necessary, thereby eliminating unnecessary examination and minimizing the burden on the subject. Will be possible.

Further, in the ophthalmic apparatus according to the embodiment, the control unit may select the cataract mode when the intensity of the component of the interference light corresponding to the fundus (fundus Ef) of the eye to be inspected is equal to or less than a predetermined threshold value.

With such a configuration, it is possible to select the cataract mode when the eye to be inspected may be "nuclear cataract" or "subcapsular cataract". In addition, there is a possibility that the eye to be inspected has "cortical cataract" by determining whether or not the intensity of the component of the interference light is equal to or less than the predetermined threshold value at a predetermined position of the eye to be inspected (for example, the outer peripheral portion of the crystalline lens). It is possible to select the cataract mode when there is.

Further, the ophthalmic apparatus according to the embodiment includes a glare light source (glare light source 47) for performing a glare test and an optotype projection system (objective projection system 4) for projecting an optotype on the eye to be inspected, and cataract. When the mode is selected, the control unit may at least perform a glare test.

According to such a configuration, it is determined whether or not the eye to be inspected is a cataract eye based on the detection results of a plurality of interfering lights obtained by the interference optical system at a plurality of positions of the eye to be inspected, and the determination result is used. The cataract mode can be selected based on. As a result, the eye to be examined is objectively and accurately measured before the glare examination, and the glare examination is performed only when necessary, thereby eliminating unnecessary glare examination and minimizing the burden on the subject. It becomes possible to suppress it.

Further, in the ophthalmic apparatus according to the embodiment, the irradiation position changing unit may include a deflection unit (optical scanner 87b) that deflects the measurement light.

According to such a configuration, the device can be miniaturized, and it is possible to acquire the detection results of a plurality of interference lights by the interference optical system at a plurality of positions in the eye to be inspected with a simple configuration and control.

Further, in the ophthalmic apparatus according to the embodiment, the deflection portion may include an optical scanner (optical scanner 87b) arranged at a position optically conjugate with the fundus of the eye to be inspected.

According to such a configuration, the device can be miniaturized, and it is possible to acquire the detection results of a plurality of interference lights by the interference optical system at a plurality of positions in the crystalline lens (pupil) of the eye to be inspected with a simple configuration and control. Become.

Further, in the ophthalmic apparatus according to the embodiment, the irradiation position changing unit may include a moving mechanism that translates the optical path of the measurement light toward the eye to be inspected.

According to such a configuration, it is possible to acquire the detection results of a plurality of interference lights by the interference optical system at a plurality of positions in the eye to be inspected with a simple configuration and control.

Further, the ophthalmic apparatus according to the embodiment may include an intraocular distance calculation unit (intraocular distance calculation unit 122) for obtaining the intraocular distance in the eye to be inspected based on the detection result of the interference light by the interference optical system.

According to such a configuration, the state of the eye to be inspected can be objectively and accurately measured by using an interference optical system capable of determining the intraocular distance, and the result of the objectively accurate measurement can be obtained. Based on this, it becomes possible to select the measurement mode of the eye to be inspected.

Further, in the ophthalmic apparatus according to the embodiment, the intraocular distance calculation unit may obtain at least one of the axial length, the anterior chamber depth, the crystalline lens thickness, and the corneal thickness.

According to such a configuration, the visual axis of the eye to be inspected can be stabilized and the intraocular distance can be obtained while the eye is adjusted to a distant point. At least one measurement of corneal thickness is possible.

<Other modifications>
The embodiments shown above are merely examples for carrying out the present invention. A person who intends to carry out the present invention can make arbitrary modifications, omissions, additions, etc. within the scope of the gist of the present invention.

In the above-described embodiment or a modified example thereof, the case where the fundus Ef or the crystalline lens of the eye E to be inspected is mainly line-scanned has been described, but other scanning methods such as raster scan, circle scan, and spiral scan may be used. ..

In the above-described embodiment or a modification thereof, the case where the crystalline lens 89 is inserted and removed between the relay lens 86 and the mirror 87a has been described, but the configuration of the ophthalmic apparatus according to the embodiment is not limited to this. .. The crystalline lens 89 can be inserted and removed at an arbitrary position in the optical path of the measurement light.

In the above-described embodiment or a modification thereof, a case where a transmissive liquid crystal panel is used as the optotype chart 42 has been described, but the configuration of the ophthalmic apparatus according to the embodiment is not limited to this. The optotype chart 42 may be an optical chart.

In the above-described embodiment or a modification thereof, the case of selecting the measurement mode in which the glare inspection is performed based on the measurement result of the optical interference measurement has been described. Applicable to what you choose.

1 Z alignment system 2 XY alignment system 3 kerato measurement system 4 optotype projection system 5 observation system 6 reflex measurement projection system 7 reflex measurement light receiving system 8 intraocular distance measurement system 9 processing unit 80 interferometer unit 87b, 87c optical scanner 110 control Unit 111 Main control unit 130 Analysis unit 1000 Ophthalmic device

Claims (5)

The light from the light source is divided into a reference light and a measurement light, the measurement light is irradiated to the eye to be inspected, an interference light between the return light and the reference light is generated, and the generated interference light is detected. Optical system and
A first optical scanner arranged between the eye to be inspected and the interference optical system at a position substantially conjugate with the pupil of the eye to be inspected.
A second optical scanner arranged between the eye to be inspected and the interference optical system at a position substantially conjugate with the fundus of the eye to be inspected.
At least a control unit that controls the first optical scanner and the second optical scanner,
By controlling at least one of the first optical scanner and the second optical scanner to deflect the measurement light, it corresponds to the detection result of the interference light obtained by the interference optical system at a plurality of positions of the eye to be inspected. An analysis unit that determines the type of cataract based on the intensity distribution of the interference signal,
Including
Wherein, when the type of the cataract Ri by the analyzing unit determines, wherein the subject's eye and cataracts mode check is performed to determine whether a cataract eye inspection is not performed An ophthalmic apparatus that selects the cataract mode from a plurality of measurement modes of the eye to be inspected , including a normal mode. The ophthalmic apparatus according to claim 1, wherein the second optical scanner is movable in the optical axis direction. The ophthalmic apparatus according to claim 1 or 2, wherein the control unit exclusively controls the first optical scanner and the second optical scanner. The invention according to any one of claims 1 to 3, wherein the intraocular distance calculation unit for obtaining the intraocular distance in the eye to be inspected is included based on the detection result of the interfering light by the interfering optical system. Ophthalmic device. The ophthalmic apparatus according to claim 4, wherein the intraocular distance calculation unit obtains at least one of axial length, anterior chamber depth, crystalline lens thickness, and corneal thickness.

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