Ophthalmologic apparatus

Abstract

To provide a technology capable of realizing a device capable of photographing both eyes at a low cost.SOLUTION: An ophthalmologic apparatus includes: an illumination optical system which illuminates anterior ocular segments of both eyes to be tested; an imaging optical system which includes coupling mirrors, a pair of mirrors that guide, to the pair of coupling mirrors, reflection light from the respective anterior ocular segments of both eyes illuminated, and one imaging device that captures images of the respective anterior ocular segments of both eyes on the basis of the reflection light from the coupling mirror; and a control part for causing the imaging device to perform imaging.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an ophthalmic device. [Background technology]

[0002] In recent years, from the viewpoint of preventive medicine, there is a demand for a device capable of easily screening for eye diseases in commercial facilities, drug stores, etc. Patent Document 1 discloses that both eyes of the face are included in the imaging range in order to improve the alignment workability. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-40793 Summary of the Invention [Problem to be solved by the invention]

[0004] In the case of the configuration of Patent Document 1, the entire face including both eyes is photographed at a low magnification, so rough alignment is possible, but it is not suitable for precise alignment. A high-magnification zoom mechanism is necessary for precise alignment, but in that case, both eyes cannot be photographed. Furthermore, it is necessary to provide a zoom mechanism and a drive unit for moving the measuring unit in front of the left and right eyes, which causes a problem that the device becomes large-scale. The present invention has been made in consideration of the above problems, and has an object to provide a technique that can realize an apparatus for photographing both eyes at low cost. [Means for solving the problem]

[0005] In order to achieve the above-mentioned objective, the ophthalmic apparatus comprises an illumination optical system that illuminates each of the anterior segments of both of the examinee's eyes, an imaging optical system including a coupling mirror, a pair of mirrors that guide reflected light from each of the illuminated anterior segments of both of the eyes to the pair of coupling mirrors, and one imaging element that images each of the anterior segments of both of the eyes based on the reflected light from the coupling mirror, and a control unit that causes the imaging element to capture an image.

[0006] That is, because this ophthalmic device is configured to capture images of both eyes with one image sensor, costs can be reduced compared to when each eye is captured with a separate image sensor. Also, because both eyes can be captured at once with one image sensor, the subject does not need to move the ophthalmic device left and right when capturing images of the right eye and the left eye, and the examination time can be shortened. [Brief description of the drawings]

[0007] [Figure 1] 1A and 1B are diagrams showing the external appearance of an ophthalmic apparatus. [Diagram 2] 1 is a block diagram showing a configuration of an ophthalmologic apparatus; [Diagram 3] FIG. 1 is a diagram showing a configuration of an optical system according to a first embodiment. [Figure 4] 4A, 4B, and 4C are schematic diagrams for explaining reflection at a coupling mirror. [Diagram 5] FIG. 5A is a diagram showing an example of a captured image before processing, and FIG. 5B is a diagram showing an example of a captured image after processing. [Figure 6] FIG. 2 is a diagram illustrating an example of the configuration of a measurement optical system. [Figure 7] FIG. 7A is a diagram for explaining tracking, and FIG. 7B is a diagram for explaining scanning. [Figure 8] 13 is a flowchart of a measurement process. [Figure 9] FIG. 13 is a diagram showing the configuration of an optical system according to a second embodiment. [Figure 10] FIG. 10A is a schematic diagram for explaining the configuration of the imaging optical system according to the second embodiment, and FIG. 10B is a schematic diagram showing a comparative example. [Figure 11]FIG. 13 is a diagram showing the configuration of an optical system as a modified example of the second embodiment. [Figure 12] FIG. 13 is a diagram showing the configuration of an optical system according to a third embodiment. [Figure 13] FIG. 13 is a diagram showing the appearance of an ophthalmologic apparatus according to another embodiment. [Figure 14] FIG. 13 is a diagram showing an example of the configuration of a measurement optical system according to another embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Here, the embodiments of the present invention will be described in the following order. (1) First embodiment: (2) Second embodiment: (3) Third embodiment: (4) Other embodiments:

[0009] (1) First embodiment: 1A and 1B are explanatory diagrams showing the appearance of an ophthalmic device 100 according to an embodiment of the present invention. The ophthalmic device 100 is assumed to be used in a venue that is not a darkroom, such as a commercial facility, so that the subject can easily measure the eye characteristics by himself / herself. As shown in the figure, a light shielding section 180 is provided in a housing H that houses optical components of the ophthalmic device 100. The light shielding section 180 includes a forehead support section 181 and a side light shielding section 182. A transparent window 170 is provided surrounded by the forehead support section 181 and the side light shielding section 182. The eye characteristics are measured while the subject touches the forehead support section 181 to his / her forehead and looks into the window 170. The subject touches the forehead support section 181 to block light from above the subject. In addition, the side light shielding section 182 can block light from the side of the subject's face when the subject's forehead is in contact with the forehead support section 181. The forehead support 181 and side light shielding parts 182 block light from both eyes, so that both eyes can be photographed in a dilated state (if even one eye is too bright, both eyes will contract). The forehead support 181 and side light shielding parts 182 also allow the subject's eyes to be roughly positioned.

[0010] As shown in FIG. 2, an optical system 10 for measuring the ocular characteristics of both eyes Ea and Eb, a control unit 20, a communication unit 30, and a speaker are arranged inside the housing H of the ophthalmic apparatus 100. The control unit 20 includes a CPU, a ROM, a RAM, and a nonvolatile memory, and controls each unit of the ophthalmic apparatus 100 by executing a control program recorded in the ROM or the nonvolatile memory by the CPU. The communication unit 30 is a communication interface for wireless or wired communication with an external device. The control unit 20 can communicate with various terminals T through the communication unit 30. The terminal T is a device for inputting subject information, displaying images captured by the ophthalmic apparatus 100, and outputting the measurement results of the ocular characteristics, and the terminal T includes an input unit such as a keyboard, a touch panel, or a mouse, and a display (display unit). The terminal T may be a mobile terminal carried by the subject, or may be a PC or a tablet prepared in advance by the installer of the ophthalmic apparatus 100. A printer or the like may be further connected to the terminal T. The speaker 40 outputs voice guidance and the like to the subject.

[0011] FIG. 3 is a diagram showing the configuration of the optical system 10 of the ophthalmic apparatus 100 according to the first embodiment. The optical system 10 of the first embodiment includes an illumination optical system, an imaging optical system, and a measurement optical system. 109 is an imaging element. As shown in FIG. 3, a direction parallel to one side of the rectangular light receiving surface of the imaging element 109 is defined as the x-axis, and a direction parallel to a side perpendicular to the side of the light receiving surface is defined as the y-axis. The light receiving surface of the imaging element 109 is parallel to the xy plane. The z-axis is an axis perpendicular to the x-axis and y-axis. An illumination optical system for illuminating the anterior segments of both eyes of a subject includes light sources 101a and 101b, half mirrors 102a and 102b, dichroic mirrors 103a and 103b, and objective lenses 104a and 104b. Ea indicates the left eye of the subject, and Eb indicates the right eye of the subject. With respect to plane A which passes through the center of the light receiving surface of image sensor 109 and is parallel to the yz plane, light sources 101a and 101b, half mirrors 102a and 102b, dichroic mirrors 103a and 103b, and objective lenses 104a and 104b are arranged symmetrically.

[0012] Light emitted from light sources 101a and 101b is reflected by half mirrors 102a and 102b, and passes through dichroic mirrors 103a and 103b. The light that has passed through the dichroic mirrors 103a and 103b is collimated by objective lenses 104a and 104b, and illuminates the subject's eye.

[0013] The wavelength of the light emitted by the light sources 101a and 101b is about 800 nm, and the subject sees a red dot in the distance. The light sources 101a and 101b illuminate the entire anterior segment of the eye and form a virtual image at the corneal apex of the subject's eye. The position of the corneal apex of the subject's eye can be obtained by detecting this virtual image. Based on the position of the corneal apex, the subject is guided to shift the position of his / her head relative to the housing H, and the angle of the movable mirror 110, which will be described later, is adjusted to scan the measurement light.

[0014] The imaging optical system includes mirrors 105a and 105b, circular apertures 106a and 106b, imaging lenses 107a and 107b, a coupling mirror 108, and an image sensor 109. Mirrors 105a and 105b, circular apertures 106a and 106b, imaging lenses 107a and 107b, and coupling mirror 108 are each disposed symmetrically with respect to plane A. Furthermore, coupling mirror 108 is a combination of mirrors 108a and 108b, and is disposed so that the intersection of mirrors 108a and 108b is located on plane A and is symmetrical.

[0015] The light emitted from the light sources 101a and 101b is scattered in the anterior segment of the eye, and a part of the scattered light passes through the objective lenses 104a and 104b and then through the dichroic mirrors 103a and 103b. The light that passes through the dichroic mirrors 103a and 103b passes through the half mirrors 102a and 102b and is reflected by the mirrors 105a and 105b.

[0016] The circular openings 106a and 106b pass a part of the reflected light from the pair of mirrors 105a and 105b. The light that passes through the circular openings 106a and 106b passes through the imaging lenses 107a and 107b and is imaged on the mirrors 108a and 108b. The mirrors 108a and 108b that constitute the combined mirror 108 are arranged at an angle that reflects the incident light at a substantially right angle (right angle ± a preset angle) to the optical axis of the pair of imaging lenses 107a and 107b. The preset angle includes 0 degrees and may be a value larger than 0 degrees as long as the vignetting described later falls within an acceptable range. The image sensor 109 is arranged so that the light receiving surface is parallel to the optical axis of the imaging lenses 107a and 107b. In other words, the mirrors 108a and 108b are arranged so that the angle that they make with the light receiving surface of the image sensor 109 is 45 degrees.

[0017] If the combining mirror 108 were not provided, the light transmitted through the imaging lenses 107a and 107b would form an image of the anterior segment of each of the two eyes slightly behind the plane A (for example, 0.5 mm behind the plane A). The combining mirror 108 is provided so that the intersection of the mirrors 108a and 108b is close to the image sensor 109. Specifically, for example, the intersection is in contact with the protective glass of the image sensor 109 or is provided so that the intersection is approximately 0.2 mm away from the protective glass. By providing the intersection of the combining mirror 108, which is located on the plane A, close to the image sensor 109, it is possible to prevent the images of the anterior segments of the left and right eyes from mixing with each other's display areas near the boundary between the binocular images where the light receiving surface of the image sensor 109 and the plane A intersect.

[0018] The pair of imaging lenses 107a and 107b are disposed between the pair of circular apertures 106a and 106b and the coupling mirror 108, respectively. The circular apertures 106a and 106b are disposed at the rear focal points of the objective lenses 104a and 104b (object-side telecentric). Therefore, even if the position of the subject's eye is shifted in the front-rear direction from a pre-determined position (because the positional relationship between the forehead rest 181 and the anterior eye segment may differ depending on the subject), the image of the anterior eye segment is blurred without changing the magnification, so that the position detection error of the corneal apex can be reduced. In addition, the circular apertures 106a and 106b are disposed at the front focal points of the imaging lenses 107a and 107b (image-side telecentric). Therefore, the chief ray of the light transmitted through the imaging lenses 107a and 107b becomes parallel to the optical axis of the imaging lenses 107a and 107b, enters the mirrors 108a and 108b, and is reflected at a right angle to enter the image sensor 109.

[0019] 4A is a schematic diagram showing how light transmitted through imaging lens 107a is incident on mirror 108a and reflected at a right angle. By making imaging lenses 107a and 107b telecentric on the image side, it is possible to prevent the images of the left and right eyes from crossing the boundary line (a line parallel to the y-axis) between the left and right centers of image sensor 109 and being reflected on the other side.

[0020] If the imaging lens 107a is arranged so that the angle a between the incident light and the reflected light on the mirror 108a is an acute angle as shown in FIG. 4B, the light in the peripheral portion is blocked by the image sensor 109, and a shadow portion is generated in the image captured by the image sensor 109 (vignetting). If the imaging lens 107a is arranged so that the angle a on the mirror 108a is an obtuse angle as shown in FIG. 4C, the light is directly incident on the image sensor 109 without being reflected by the mirror 108a, or the component reflected by the protective glass of the image sensor 109 and then by the mirror 108a becomes noise and is incident on the image sensor 109. However, as in the present embodiment shown in FIG. 4A, the imaging lens 107a, the mirror 108a, and the image sensor 109 are arranged so that the light is reflected at a right angle to the principal ray, and the reflected light is incident at a right angle on the light receiving surface of the image sensor 109, thereby preventing the occurrence of such a phenomenon (vignetting or noise due to stray light). Furthermore, this embodiment does not require any optical components between the coupling mirror 108 and the image sensor 109 as shown in the second embodiment, and therefore costs can be reduced.

[0021] FIG. 5A shows an example of an image thus captured by the image sensor 109. As shown in FIG. 5A, in the captured image, the left half is an image showing the left eye of the subject, and the right half is an image showing the right eye. In addition, both left and right ends of the entire captured image are images of the center side (nose side) of the subject's face. For this reason, the control unit 20 performs image processing on the image of both eyes captured by the image sensor 109 so as to switch the left and right eyes, thereby generating an image as shown in FIG. 5B. That is, in the processed image, the left half is an image showing the right eye, the right half is an image showing the left eye, and the center of the image is an image of the center side (nose side) of the face. Then, the control unit 20 outputs the image in which the left and right eyes have been switched in this way to the terminal T via the communication unit 30. An image as shown in FIG. 5B can be displayed on the display unit of the terminal T. As a result, the subject himself or the examiner can easily intuitively distinguish the left eye from the right eye from this image, and misrecognition of the left and right images can be prevented.

[0022] FIG. 6 is a diagram showing the configuration of the objective refractive power measurement optical system in this embodiment. The configuration of the measurement optical system will be described with reference to FIG. 3 and FIG. 6. FIG. 6 shows a specific example of the optical system 111 shown in FIG. 3 and a movable mirror 110. The measurement optical system includes a light source 121 that generates measurement light, a movable mirror 110 that selectively switches the irradiation direction of the measurement light to the directions of both eyes and irradiates both eyes, and a measurement unit that receives the measurement light reflected from both eyes. The optical components designated by 122 to 130 correspond to the measurement unit.

[0023] The light emitted from the light source 121 is collimated by the lens 122, passes through the polarizing beam splitter 123, and is focused on the movable mirror 110 by the lens 124. The light emitted from the light source 121 is adjusted in polarization so that it becomes P-polarized light with respect to the polarizing beam splitter 123. As a result, the light emitted from the light source 121 is transmitted through the polarizing beam splitter 123 at almost 100%.

[0024] The movable mirror 110 is configured by combining two uniaxial mirrors, for example. Alternatively, the movable mirror 110 may be configured to drive one mirror on two axes. In either case, it is configured to be able to control the irradiation position of the measurement light in two dimensions. The control unit 20 controls the driving unit (not shown) to drive the movable mirror 110 so that the angle is set so that the light is selectively irradiated to the right eye Eb or the left eye Ea. FIG. 3 shows an example in which the measurement light is irradiated to the left eye Ea. The light collected on the movable mirror 110 is reflected to be irradiated to the left eye Ea, reflected by the dichroic mirror 103a, and made parallel to the optical axis of the objective lens 104a by the objective lens 104a and irradiated to the subject's eye. The light irradiated to the subject's eye is collected and scattered near the fundus. When the subject's eye is an emmetropic eye, a part of the light scattered at the fundus is reflected by the objective lens 104a and the dichroic mirror 103a, and collected on the movable mirror 110. The collected light is collimated by the lens 124 (see FIG. 6), and only the S-polarized component is reflected by the polarizing beam splitter 123. The light reflected by the polarizing beam splitter 123 is reflected by the mirror 125, and is collected by the lens 126 at the opening of the circular aperture 127. The light passing through the circular aperture 127 is collimated by the lens 128, and is converted into a ring-shaped beam by the ring lens 129 and projected onto the image sensor 130. If the subject's eye is not emmetropic, the angle of incidence on the ring lens 129 is different from that of an emmetropic eye, and the ring diameter imaged by the image sensor 130 is also different from that of an emmetropic eye (for example, the ring diameter is smaller in the case of a myopic eye, and larger in the case of a hyperopic eye). The control unit 20 acquires the ocular refractive power of the subject's eye based on the ring diameter imaged by the image sensor 130.

[0025] In addition, the control unit 20 detects the position of the corneal apex C (see FIG. 7A) in the captured image and calculates the positional relationship in the image with respect to the reference point P (the offset (number of pixels) of the horizontal component of the image and the offset (number of pixels) of the vertical component of the image). The control unit 20 specifies the driving amount of the movable mirror 110 according to the above-mentioned positional relationship, and drives the movable mirror 110. In this way, the scanning range of the measurement light is controlled so that the measurement light is incident on a predetermined range based on the corneal apex C of the subject's eye, and the eye refractive power can be measured in an aligned state. This provides higher tracking ability than a case in which the light source 121 or the measurement unit is moved to align the eye, and can improve the inspection accuracy. The predetermined range is determined in advance for each measurement target in the measurement optical system. For example, when measuring the eye refractive power, a circular range with a predetermined radius centered on the corneal apex C or a rectangular range including the circle is determined as the predetermined range. The control unit 20 regards a position shifted from the reference point P by an offset amount indicating the positional relationship between the reference point P and the corneal apex C, i.e., the position of the corneal apex C, as the center of the predetermined range. Then, the control unit 20 specifies the driving amount of the movable mirror 110 so that the subject's eye is scanned from the center over the predetermined range, and drives the movable mirror 110. If the offset amount exceeds a predetermined value, the control unit 20 outputs a voice from the speaker 40 to prompt the subject to shift the position of his or her face. The voice message includes guidance on the direction in which the face should be moved to reduce the offset amount. As shown in Fig. 7B, the movable mirror 110 may be driven to comprehensively scan the irradiable range of the measurement light in all directions at a predetermined pitch. That is, the control unit 20 may drive the movable mirror 110 so that the light from the movable mirror 110 is irradiated over a range wide enough to measure the measurement target in the measurement optical system. In this case, the control unit 20 extracts and adopts measurement data obtained when a predetermined range based on the corneal apex is irradiated based on the offset amount described above from the measurement results by the measurement optical system. In the axial length measurement described later, the measurement data obtained when the light matches the corneal apex when the light is irradiated comprehensively as described above may be adopted.

[0026] FIG. 8 is a flowchart showing the measurement process. The measurement process is executed when a process start trigger is detected. In this embodiment, the process start trigger is reception of subject information from terminal T. The subject information is assumed to be, for example, information for identifying the subject (e.g., name, patient ID, etc.) and information indicating the subject's attributes (e.g., age group, gender, etc.). When the subject information is received from terminal T via communication unit 30, control unit 20 acquires the subject information (step S100) and starts imaging (step S105). That is, control unit 20 causes image sensor 109 to repeatedly capture images at a predetermined cycle.

[0027] When the subject brings the ophthalmic device 100 into contact with the face, the brightness of the image captured by the image sensor 109 becomes lower than that before the face touches the ophthalmic device. Using this, the control unit 20 is configured to start measurement control of the eye characteristics when the brightness of the image captured by the image sensor 109 becomes equal to or lower than a threshold value. As the brightness of the image, for example, a statistical value (mode, average value, etc.) of the brightness of each pixel in the image captured by the image sensor 109 is adopted. In step S110, the control unit 20 waits until the brightness becomes equal to or lower than the threshold value. In this way, by using the brightness becoming equal to or lower than the threshold value as a trigger for starting the measurement, it is not necessary for the subject to perform a special operation for starting the measurement control, and the burden on the operator can be reduced. Note that the "measurement control" includes a tracking control for tracking the measurement light so that the measurement light is irradiated within a predetermined range based on the corneal apex C, and a control for measuring the eye characteristics after tracking is completed. In this embodiment, the processing from step S115 onwards is included in the "measurement control".

[0028] If it is determined in step S110 that the luminance is equal to or less than the threshold, that is, if it is estimated that the ophthalmologic device 100 is in contact with the face of the subject, the control unit 20 determines whether the positions of both eyes are within a predetermined range (step S115). That is, the control unit 20 determines whether the absolute value of the offset amount between the reference point P and the corneal apex C in the image is within a predetermined value for both eyes.

[0029] If it is not determined in step S115 that the eye positions are within the predetermined range, the control unit 20 performs a voice notification (step S120). For example, the control unit 20 outputs a message from the speaker 40 prompting the user to shift the position of the face relative to the ophthalmologic apparatus 100.

[0030] If it is determined in step S115 that the positions of both eyes are within the predetermined range, the control unit 20 starts tracking of the measurement light (step S125) and performs measurement (step S130). That is, the control unit 20 drives the movable mirror 110 by a drive amount derived based on the offset amount of the corneal apex C from the reference point P in the image captured by the image sensor 109, and irradiates the measurement light within a predetermined range based on the corneal apex C to measure the eye refractive power.

[0031] Next, the control unit 20 judges whether the measurement of both eyes is completed (step S135). If it is not judged that the measurement of both eyes is completed, that is, if only one eye is completed, the control unit 20 returns to the process of step S125 and measures the unmeasured eye. That is, the control unit 20 drives the movable mirror 110 so as to irradiate the measurement light in the direction of the unmeasured eye, and performs the process of step S125 and subsequent steps. That is, according to this embodiment, it is possible to measure the ocular refractive power of both eyes without moving the light source 121 or the measurement unit left and right. If it is judged that the measurement of both eyes is completed in step S135, the control unit 20 displays the measurement result (step S140). That is, the control unit 20 transmits data indicating the measurement result and the captured image to the terminal T via the communication unit 30. The terminal T displays the measurement result data and the captured image received from the ophthalmic device 100 on the display unit.

[0032] As described above, according to this embodiment, since both eyes can be photographed with one image sensor, costs can be reduced compared to a configuration in which each eye is photographed with a separate image sensor. Also, in this embodiment, the subject can photograph and measure both eyes by placing the forehead support part 181 of the ophthalmic device 100 on his / her forehead. Therefore, there is no need to shift the ophthalmic device left and right when measuring the right eye and the left eye, and the examination time can be shortened.

[0033] (2) Second embodiment: 9 is a diagram showing the optical system of an ophthalmic apparatus according to the second embodiment. The second embodiment differs from the first embodiment in the imaging optical system. The imaging optical system in the second embodiment includes a relay lens 112 and an imaging element front lens 113 in addition to the configuration of the imaging optical system in the first embodiment. Other configurations common to the first embodiment are given the same reference numerals and description thereof will be omitted. Ea indicates the left eye of the subject eye, and Eb indicates the right eye.

[0034] The image sensor front lens 113 is disposed between the combining mirror 108 and the image sensor 109. The relay lens 112 is disposed between the combining mirror 108 and the image sensor front lens 113. FIG. 10A is a diagram showing a schematic configuration of an imaging optical system according to the second embodiment, in which the optical axis direction changed by the mirrors 105a and 105b and the combining mirror 108 is expressed as being in a straight line. As shown in the figure, the image sensor front lens 113 is disposed at the rear focal point of the relay lens 112. The pair of circular openings 106a and 106b are disposed so as to be conjugate with the single image sensor front lens 113 with respect to the imaging lenses 107a and 107b, the combining mirror 108, and the relay lens 112. As a result, even if the lens diameter of the image sensor front lens 113 and the image sensor 109 are small, it is possible to form images of both eyes on the single image sensor 109 without causing vignetting.

[0035] If the relay lens 12 is not provided in the configuration of the second embodiment and the image sensor front lens 113 is small as shown in Fig. 10B, the entire principal ray of the reflected light from both eyes Ea and Eb cannot be guided to the image sensor 109. However, the relay lens 12 can be omitted in the following cases.

[0036] 11 shows a configuration example in the second embodiment in which the relay lens 112 is omitted. When the lens diameter of the image sensor front lens 113 is large enough to guide all of the principal rays of reflected light from both eyes Ea and Eb to the image sensor 109, the relay lens 112 can be omitted. In this case, the image sensor 109 is disposed at a position closer to the image sensor front lens 113 than the focal point of the image sensor front lens 113, and light reflected at a substantially right angle by the coupling mirror 108 is reduced by the image sensor front lens 113 and enters the image sensor 109.

[0037] (3) Third embodiment: The configuration of imaging both eyes with one image sensor can also be applied to a slit lamp microscope. FIG. 12 is a diagram showing the configuration of the optical system of a slit lamp microscope 200 according to the third embodiment. The slit lamp microscope 200 includes an illumination optical system, a slit light generating optical system, a scanning optical system, and an imaging optical system. The illumination optical system for illuminating the anterior segments of both eyes Ea and Eb of the subject includes light sources 208a and 208b, lenses 209a and 209b, and total reflection mirrors 210a and 210b. The light sources 208a and 208b emit near-infrared light with a wavelength of about 800 nm. The light emitted from the light sources 208a and 208b arranged symmetrically on the left and right becomes approximately parallel light by the lenses 209a and 209b, is reflected by the total reflection mirrors 210a and 210b, and passes through a window 170 to illuminate the subject's eye. Since the near-infrared light is converted into approximately parallel light, the subject is less likely to feel dazzled.

[0038] The slit light generating optical system for generating the slit light includes a light source 201 that emits white light, a lens 202, and a slit-shaped opening 203. The light emitted from the light source 201 passes through the lens 202 and is narrowed down by the slit-shaped opening 203 into a long slit shape in a direction parallel to the y-axis.

[0039] The scanning optical system for scanning the slit light and irradiating the slit light on the anterior segments of both eyes (scanning the anterior segments by shifting the irradiation position of the slit light on the anterior segments at a predetermined interval) includes a scanning mirror 204, a lens 205, and a half mirror 206. The light narrowed to a slit shape by the slit-shaped opening 203 is reflected by the scanning mirror 204. The scanning mirror 204 is rotated by a driving mechanism (not shown) to scan the slit light within a predetermined range. The reflected light of the scanning mirror 204 passes through the lens 205 to become approximately parallel light, and is divided by the half mirror 206 in the directions of the left and right eyes. The divided slit light beams are projected onto the anterior segments of both eyes of the subject's eyes through the window 170. The half mirror 206 is disposed on a plane A and divides the slit light beam symmetrically. Therefore, according to this configuration, the slit light beam can be projected onto both eyes of the subject at the same time.

[0040] The imaging optical system includes mirrors 105a and 105b, circular apertures 106a and 106b, imaging lenses 107a and 107b, a coupling mirror 108, a relay lens 112, an imaging element front lens 113, and an imaging element 109. The white slit light beam and near-infrared illumination light irradiated to the subject's eye are scattered at the anterior segment of the subject's eye, and the scattered light passes through a window 170 and is reflected by the mirrors 105a and 105b. The light reflected by the mirrors 105a and 105b is guided to the imaging element 109 via the circular apertures 106a and 106b, imaging lenses 107a and 107b, the coupling mirror 108, the relay lens 112, and the imaging element front lens 113, as in the second embodiment. That is, the mirrors 105a and 105b are a pair of mirrors that guide the slit light reflected from the anterior segments of both eyes, respectively, to a pair of combining mirrors 108 (108a and 108b). Note that, in the third embodiment as well, the relay lens 112 and the image sensor front lens 113 may be omitted, and the combining mirror 108 and the image sensor 109 may be arranged close to each other as in the first embodiment.

[0041] In this way, according to the present embodiment, both eyes can be photographed while irradiating the slit light to both eyes at the same time. In addition, since both eyes can be photographed at once with one image sensor, the subject does not need to move the ophthalmic device left and right to photograph the right eye and the left eye, so the examination time can be shortened, and further, the measurement data size can be halved compared to the case where the left and right eyes are measured separately.

[0042] (4) Other embodiments: The above embodiment is an example for carrying out the present invention, and various other embodiments can be adopted. For example, the ophthalmologic apparatus may be a portable type as shown in FIG. 1, or may be configured as a tabletop type attached or placed on a table such as a desk so that the subject can look into it as shown in FIG. 13. The light shielding part may include a light shielding part that blocks light from below. For example, if it is a portable type, a cheek rest part that comes into contact with the cheek of the subject may be provided. In addition, some of the optical components constituting the imaging optical system, the illumination optical system, and the measurement optical system may be shared.

[0043] Further, for example, in addition to the eye refractive power measurement shown in the first embodiment and the slit lamp microscope shown in the third embodiment, the ophthalmic apparatus can also be used for optical interference type axial length measurement, optical coherence tomography, confocal scanning ophthalmoscope, etc.

[0044] Fig. 14 is a diagram showing an example of the configuration of a measurement optical system for measuring the axial length, and is a diagram showing a specific example of the optical system 111 in Fig. 3. The measurement optical system for measuring the axial length includes a light source 131, a lens 132, a non-polarizing beam splitter 133, retroreflectors 134 and 135, a polarizing beam splitter 136, a λ / 4 plate 137, a lens 138, a movable mirror 110, a mirror 139, a lens 140, and a detector 141. The light emitted from the light source 131 is collimated by the lens 132 and split into two directions by the non-polarizing beam splitter 133. The component reflected by the non-polarizing beam splitter 133 is reflected by the retroreflector 134 and is reflected by the non-polarizing beam splitter 133. The component transmitted through non-polarizing beam splitter 133 is reflected by retroreflector 135, transmitted through non-polarizing beam splitter 133, and combined with the beam reflected by retroreflector 134. An optical path length difference occurs between the optical path of the light reflected by retroreflector 134 and the optical path of the light reflected by retroreflector 135. Retroreflector 135 is driven in the optical axis direction. The light combined by non-polarizing beam splitter 133 is converted into linearly polarized light having only P polarization by polarizing beam splitter 136, and is converted into circularly polarized light by λ / 4 plate 137. The beam circularly polarized by λ / 4 plate 137 is focused on movable mirror 110 by lens 138. The light collected by the movable mirror 110 is deflected so as to be irradiated to either the left or right eye, reflected by the dichroic mirror 103a or 103b (see FIG. 3), and converted into parallel light by the objective lens 104a or 104b, which is then irradiated to the subject's eye. The light irradiated to the subject's eye is reflected by the cornea and fundus. A part of the light scattered by the fundus passes through the objective lens 104a or 104b, is reflected by the dichroic mirror 103a or 103b, and is collected on the movable mirror 110. The collected light is converted into parallel light by the lens 138 (see FIG. 14), converted into linearly polarized light having only S-polarized components by the λ / 4 plate 137, and reflected by the polarizing beam splitter 136. The light reflected by the polarizing beam splitter 136 is reflected by the mirror 139, passes through the lens 140, and reaches the detector 141 together with the light reflected from the cornea. When the optical path lengths of the light reflected by the cornea and the fundus are the same, the interference signal detected by the detector 141 becomes maximum.The control unit 20 obtains the axial length of the subject's eye based on the position of the retroreflector 135 when the interference signal is maximized.

[0045] The ophthalmologic apparatus may be realized as an imaging apparatus that captures images of both eyes without the measurement optical system. The captured images may be output in the form of still images or moving images. The trigger for starting imaging in the image sensor 109 in the measurement process is not limited to that described in the above embodiment. Imaging may be started in response to an instruction from the terminal T, or may be started when an operation unit of the ophthalmic device 100 is operated (for example, when a power switch (not shown) is operated to turn on the power). When the terminal T is configured to be able to associate the measurement result in the ophthalmic device with the subject information, the subject information does not need to be transmitted to the ophthalmic device. The subject information may be input either before or after the measurement.

[0046] Furthermore, the technique of the present invention can also be applied as a program or method. The above-mentioned system, program, and method may be realized as a single device, or may be realized by using parts shared with other devices, and include various aspects. In addition, they can be modified as appropriate, such as being partly software and partly hardware. Furthermore, the invention can also be realized as a recording medium of a program that controls the system. Of course, the recording medium of the program may be a magnetic recording medium or a semiconductor memory, and any recording medium developed in the future can be considered in the same way. [Explanation of symbols]

[0047] 10...optical system, 12...relay lens, 20...control unit, 30...communication unit, 40...speaker, 100...ophthalmic device, 101a, 101b...light source, 102a, 102b...half mirror, 103a, 103b...dichroic mirror, 104a, 104b...objective lens, 105a, 105b...mirror, 106a, 106b...circular aperture, 107a, 107b...imaging lens, 108...combining mirror, 108a, 108b...mirror (combining mirror), 109...image sensor, 110...movable mirror, 112...relay lens, 113...image sensor front lens, 121...light source, 122...lens, 123...polarizing beam splitter, 124...lens, 125...mirror, 126...lens, 127...circular aperture, 128...lens, 129... ring lens, 130... imaging element, 131... light source, 132... lens, 133... non-polarizing beam splitter, 134... retroreflector, 134, 135... retroreflector, 135... retroreflector, 136... polarizing beam splitter, 138... lens, 139... mirror, 140... lens, 141... detector, 170... window, 180... light shielding portion, 181... forehead rest portion, 182... side light shielding portion, 200... slit lamp microscope, 201... light source, 202... lens, 203... slit-shaped opening, 204... scanning mirror, 205... lens, 206... half mirror, 208a, 208b... light source, 209a, 209b... lens, 210a, 210b... total reflection mirror, A... plane, C... corneal apex, H... housing

Claims

1. an illumination optical system for illuminating the anterior segments of both of the examinee's eyes; an imaging optical system including a coupling mirror, a pair of mirrors that guide reflected light from each of the illuminated anterior segments of the both eyes to the pair of coupling mirrors, and one imaging element that images each of the anterior segments of the both eyes based on the reflected light from the coupling mirror; A control unit that causes the imaging element to capture an image; An ophthalmic apparatus comprising:

2. a slit light generating optical system for generating slit light; a scanning optical system that scans the slit light and irradiates the anterior segments of the both eyes, The scanning optical system includes: A scanning mirror for scanning the slit light; a half mirror for dividing the slit light reflected by the scanning mirror and directing it to each of the anterior segments of the both eyes, The imaging optical system includes: A pair of mirrors that guide the slit light reflected from the anterior segments of the both eyes to a pair of coupling mirrors, The ophthalmic device according to claim 1 .

3. A light source for generating measurement light; a movable mirror that selectively switches the irradiation direction of the measurement light toward each of the two eyes and irradiates the measurement light toward each of the two eyes; A measurement unit that receives the measurement light reflected from both eyes. The ophthalmic device according to claim 1 .

4. the control unit rotates the movable mirror by a drive amount derived based on a positional relationship between a reference point and the corneal apex in the image captured by the imaging element. An ophthalmic apparatus according to claim 3.

5. A light shielding unit that shields both eyes from light, The control unit starts measurement control of eye characteristics when the luminance of the image captured by the image sensor becomes equal to or less than a threshold value. The ophthalmic apparatus according to any one of claims 2 to 4.

6. The imaging optical system includes: a pair of circular apertures each passing a portion of the light reflected from the pair of mirrors; a pair of imaging lenses respectively disposed between the pair of circular apertures and the coupling mirror; the circular aperture is located at a front focal point of the imaging lens; the coupling mirror is disposed at an angle such that it reflects at a substantially right angle with respect to the optical axis of the pair of imaging lenses, The image sensor is disposed so that a light receiving surface is parallel to the optical axis of the imaging lens. The ophthalmic device according to claim 1 .

7. the imaging optical system includes one imaging element front lens disposed between the coupling mirror and the imaging element, An ophthalmic apparatus according to claim 6.

8. the imaging optical system includes a relay lens disposed between the coupling mirror and the imaging element front lens, The image sensor front lens is disposed at the rear focal point of the relay lens. An ophthalmic apparatus according to claim 7.

9. The control unit processes the images of the two eyes captured by the imaging element so as to switch the left and right eyes, and causes a display unit to display the images in which the left and right eyes have been switched. The ophthalmic device according to claim 1 .

Images