JP2018082918A - Ophthalmologic imaging apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ophthalmologic imaging apparatus that effectively removes a noise light in SLO (scanning laser ophthalmoscope) imaging.SOLUTION: A projection system of an ophthalmologic imaging apparatus projects a light output from a light source 1 onto the ocular fundus Ef of an eye to be examined through an optical scanner 9 and an objective lens 11. The projection system includes a diaphragm member 15 disposed between the light source and an optical path composition member 5 for limiting a beam size of the light output from the light source. A detection system guides a return light from the eye to be examined to a light detector 16 through the objective lens and the optical scanner. The light path composition member composites a light path of the projection system and a light path of the detection system. The light path composition member includes a first region and a second region. The first region is larger than a beam size of a light transmitting the diaphragm member and causes the light transmitting the diaphragm member to enter a light path heading to the optical scanner. The second region is provided in the surrounding of the first region, and causes a part of the return light to enter a light path heading to the light detector. An image forming part forms an image of the ocular fundus based on the output from the light detector.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an ophthalmologic photographing apparatus.

  Image diagnosis occupies an important position in the field of ophthalmology, and in recent years, the use of a scanning laser ophthalmoscope (SLO) is progressing. The SLO is an apparatus that forms an image by scanning the fundus at high speed with a weak laser beam using a confocal optical system, and is used for screening and diagnosis of eye diseases.

  Ghosts (flares) caused by various noise lights are mixed in the SLO image. Noise light that causes ghost includes reflected light from an optical element such as an objective lens and reflected light from an eye tissue such as a cornea.

  A technique disclosed in Patent Document 1 is known as a technique for removing noise light. In the invention disclosed in Patent Document 1, the light shielding member 22 is disposed at a position optically conjugate with the lens surface 17a of the objective lens system 17, so that the reflected light from the lens surface 17a does not enter the light receiving element 25. I am doing so.

JP 2016-28687 A

  However, as described below, it is difficult to effectively remove noise light with the technique disclosed in Patent Document 1.

  In general, in an ophthalmologic apparatus that scans the fundus with light, an optical scanner is disposed at a position optically conjugate with the pupil. This is because in order to scan the fundus widely through the narrow pupil, it is necessary to place the center of scanning in the pupil.

  Actually, in Patent Document 1, the laser light from the scanning unit 16 is swiveled around a turning point P set at the front position of the crystalline lens. On the other hand, the light shielding member 22 is disposed at a position optically conjugate with the lens surface 17 a and is not disposed at a position optically conjugate with the scanning unit 16. Therefore, the reflected light from the lens surface 17 a is deflected by the scanning unit 16, and thus passes through a position that is (relatively) greatly deviated from the optical axis when it reaches the light shielding member 22. Therefore, in the configuration in which the light shielding member 22 is disposed at a position optically conjugate with the lens surface 17a, it is difficult to effectively block the reflected light from the lens surface 17a.

  An object of the present invention is to effectively remove noise light in SLO imaging.

A first aspect of the ophthalmologic photographing apparatus according to the embodiment includes a projection system that projects light output from a light source onto a fundus of an eye to be examined via an optical scanner and an objective lens, and return light from the eye to be examined. Based on an output from the photodetector, a detection system that guides the optical system to the photodetector via the objective lens and the optical scanner, an optical path synthesis member that synthesizes the optical path of the projection system and the optical path of the detection system An image forming unit that forms an image of the fundus oculi, and the projection system includes a diaphragm member that is disposed between the light source and the optical path combining member and limits a beam size of light output from the light source. The optical path combining member is larger than a beam size of the light that has passed through the aperture member, and has a first region that makes the light that has passed through the aperture member incident on the optical path toward the optical scanner, and the periphery of the first region Provided in front Characterized in that a part of the return light and a second region to be incident on the optical path toward the photodetector.
In the second aspect of the ophthalmologic photographing apparatus according to the embodiment, the first region of the optical path combining member may include a region where light that has passed through the diaphragm member is projected, and is larger than the projection region. It's okay.
In the third aspect of the ophthalmologic photographing apparatus according to the embodiment, the optical path combining member may be provided obliquely with respect to each of the optical path of the projection system and the optical path of the detection system. Furthermore, the first region may be a first reflection region that reflects light, and the second region may be a first transmission region that transmits light.
In the fourth aspect of the ophthalmologic photographing apparatus according to the embodiment, the first reflection region may reflect the light that has passed through the diaphragm member and enter the light path toward the optical scanner, and the return light Of these, the projected portion may be reflected in a direction different from the optical path toward the photodetector. Furthermore, the first transmission region may transmit a portion of the return light projected thereto and enter the light path toward the photodetector.
In the fifth aspect of the ophthalmologic photographing apparatus according to the embodiment, the optical path combining member may be provided obliquely with respect to each of the optical path of the projection system and the optical path of the detection system. Furthermore, the first region may be a second transmission region that transmits light, and the second region may be a second reflection region that reflects light.
In the sixth aspect of the ophthalmologic photographing apparatus according to the embodiment, the second transmission region may transmit the light that has passed through the diaphragm member and may be incident on an optical path toward the optical scanner, and may return the return light. Of these, the projected portion may be transmitted in a direction different from the optical path toward the photodetector. Further, the second reflection region may reflect a portion of the return light projected onto the light and enter the light path toward the photodetector.
In the seventh aspect of the ophthalmologic photographing apparatus according to the embodiment, the optical path combining member may be disposed at a position optically conjugate with the cornea of the eye to be examined.

  According to the embodiment, noise light in SLO imaging can be effectively removed.

It is the schematic which shows an example of a structure of the ophthalmologic imaging device which concerns on embodiment. It is the schematic which shows an example of a structure of the ophthalmologic imaging device which concerns on embodiment. It is the schematic for demonstrating an example of a structure of the ophthalmologic imaging device which concerns on embodiment. It is the schematic which shows an example of a structure of the ophthalmologic imaging device which concerns on embodiment.

  An exemplary embodiment of an ophthalmic imaging device is described below. The contents of cited documents and known techniques can be incorporated into the embodiments.

  The ophthalmologic photographing apparatus according to the embodiment is an SLO that scans the fundus with a light beam to form an image. The ophthalmologic photographing apparatus according to the embodiment may include only the SLO function or may further include other functions. The other function may be any photographing function or any measurement function. In an exemplary embodiment, the ophthalmic imaging apparatus may include an SLO function and an optical coherence tomography (OCT) function.

  Hereinafter, unless otherwise specified, a direction along the optical axis of the objective lens is defined as a Z direction, a predetermined direction orthogonal thereto is defined as an X direction, and a direction orthogonal to both the X direction and the Z direction is defined as a Y direction. Typically, the left-right direction based on the subject can be the X direction, and the up-down direction can be the Y direction. The X direction, the Y direction, and the Z direction define a three-dimensional orthogonal coordinate system.

  Examples of the configuration of an ophthalmologic photographing apparatus according to one embodiment are shown in FIGS. FIG. 1 shows an example of an optical system. FIG. 2 shows an example of an optical element (optical path combining member 5) that combines the optical path of the projection system and the optical path of the detection system. FIG. 3 shows an example of the state of the light beam in the optical path combining member 5. FIG. 4 shows an example of a processing system.

<Optical system>
The optical system shown in FIG. 1 collects data by scanning the fundus oculi Ef of the eye E with a light beam. For this purpose, the optical system includes a projection system that projects a light beam for scanning onto the fundus oculi Ef, and a detection system that detects return light from the eye E of the light beam projected onto the fundus oculi Ef. An image of the fundus oculi Ef is constructed based on the output from the detection system (that is, data collected by the optical system).

  In other embodiments, in addition to such an SLO optical system, an OCT optical system for performing an OCT scan, an anterior ocular segment imaging system for observing and photographing the anterior segment, and fixation on the fundus oculi Ef A fixation system for projecting a target, an index projection system for projecting an alignment index or a focus index, and the like may be provided. The optical system may be movable in the X direction, the Y direction, and the Z direction. Thereby, alignment and tracking of the optical system can be performed.

  In the optical system schematically shown in FIG. 1, the projection system includes a first light source 1A, a first collimating lens 2A, a first aperture 3A, a second light source 1B, a second collimating lens 2B, and a second aperture 3B. A dichroic mirror (or half mirror) 4, an optical path combining member 5, a lens 6, a reflection mirror 7, a lens 8, an optical scanner 9, a relay lens 10, and an objective lens 11.

  The first light source 1A and / or the second light source 1B may be an external light source that is not included in the projection system (ophthalmologic photographing apparatus). In this case, for example, the light generated by the first light source 1A (or the second light source 1B) is guided to the projection system through an optical fiber (not shown). Similarly, the first collimating lens 2A and the second collimating lens 2B may be provided outside the projection system.

  The number of light sources is not limited to two, and may be an arbitrary number of one or more. The wavelength of light output from the light source is also arbitrary. For example, the light source may include at least one of an infrared light source having an arbitrary wavelength band and a visible light source having an arbitrary wavelength band.

  In one example, the first light source 1A is a visible light source that outputs light having a wavelength of 532 nm, and the second light source 1B is a near-infrared light source that outputs light having a wavelength of 800 nm. Each of the first light source 1A and the second light source 1B includes, for example, a laser diode, a super luminescent diode, or a laser-driven light source. In a state in which the alignment is suitable, each of the first light source 1A and the second light source 1B is disposed at a position (or in the vicinity thereof) optically conjugate with the fundus oculi Ef.

  The first collimating lens 2A turns the light output from the first light source 1A into a parallel light flux. The first diaphragm 3A limits the beam size of the parallel light beam generated by the first collimating lens 2A. The beam size is an arbitrary parameter that represents the size of the cross section of the parallel light flux, and may be, for example, the diameter or cross sectional area of the beam. The light that has passed through the opening of the first aperture stop 3 </ b> A is guided to the dichroic mirror 4. The optical path (first scanning optical path) from the first light source 1A to the dichroic mirror 4 is denoted by reference numeral OP1. A polarizer may be provided in the first scanning optical path OP1. The polarizer generates linearly polarized light having a predetermined polarization axis. When the first light source 1A outputs linearly polarized light, such a polarizer is not necessary.

  Similarly, the second collimating lens 2B turns the light output from the second light source 1B into a parallel light flux. The second diaphragm 3B limits the beam size of the parallel light beam generated by the second collimating lens 2A. The light that has passed through the opening of the second aperture stop 3B is guided to the dichroic mirror 4. An optical path (second scanning optical path) from the second light source 1B to the dichroic mirror 4 is denoted by reference symbol OP2. A polarizer that generates linearly polarized light having a predetermined polarization axis may be provided in the second scanning optical path OP2. Such a polarizer is unnecessary when the second light source 1B outputs linearly polarized light.

  The dichroic mirror 4 combines the first scanning optical path OP1 and the second scanning optical path OP2. In other words, the dichroic mirror 4 transmits light (scanning light) incident from the first scanning optical path OP1 and reflects light (scanning light) incident from the second scanning optical path OP2. Conversely, a configuration using a dichroic mirror (or a half mirror) that reflects the scanning light incident from the first scanning optical path OP1 and transmits the scanning light incident from the second scanning optical path OP2 can also be applied. . An optical path between the dichroic mirror 4 and the optical path combining member 5 (that is, a combined optical path of the first scanning optical path OP1 and the second scanning optical path OP2 formed by the dichroic mirror 4) is referred to as a scanning optical path OP3.

  In this example, the dichroic mirror 4 combines the optical axis of the first scanning optical path OP1 and the optical axis of the second scanning optical path OP2. In other words, the dichroic mirror 4 synthesizes the first scanning optical path OP1 and the second scanning optical path OP2 coaxially. The scanning light that has passed through the first aperture stop 3A travels on and near the optical axis of the first scanning optical path OP1, passes through the dichroic mirror 4, travels on and near the optical axis of the scanning optical path OP3, and combines the optical paths. Projected onto member 5. Similarly, the scanning light that has passed through the second aperture stop 3B travels on and near the optical axis of the second scanning optical path OP2, is reflected by the dichroic mirror 4, and travels on and near the optical axis of the scanning optical path OP3. Is projected onto the optical path combining member 5.

  The optical path combining member 5 combines the optical path of the projection system and the optical path of the detection system. In this example, the optical path combining member 5 combines a scanning optical path OP3 and a detection optical path OP5 described later. The optical path combining member 5 reflects the scanning light incident from the scanning optical path OP3 and causes the scanning light to enter the optical path OP4 toward the eye E. Further, the optical path combining member 5 transmits a part of the return light from the eye E to be incident through the optical path OP4 and enters the detection optical path OP5. An example of such an optical path combining member 5 is shown in FIG. In other embodiments, the optical path combining member may be configured and / or arranged to transmit scanning light and reflect return light from the eye E.

  The optical path combining member 5 shown in FIG. 2 includes a transmission part 5a and a reflection part 5b. In this example, the reflecting portion 5b is formed in a disc shape, but these may be in other shapes. When the optical path combining member 5 is arranged as shown in FIG. 1, the shape of the reflecting portion 5b is determined according to the inclination angle of the optical path combining member 5 with respect to at least one of the scanning optical path OP3, the optical path OP4, and the detection optical path OP5. can do. For example, the reflection part 5b can be formed in an elliptical plate shape so that the apparent contour of the reflection part 5b is circular when viewed from the direction along the scanning optical path OP3, the optical path OP4, and the detection optical path OP5.

  The reflection part 5b reflects the scanning light incident from the scanning optical path OP3 and guides it to the eye E. The reflecting part 5b is, for example, a reflecting mirror, or may be a thin film or a coating having a light reflecting action. The center (or the center of gravity, etc.) of the reflecting portion 5b is substantially disposed on the optical axis of the scanning optical path OP3. The reflector 5b is designed to have a size that can reflect the entire beam cross section of the scanning light, for example. Typically, as shown in FIG. 3, the beam cross section R1 of the scanning light defined by the first diaphragm 3A or the second diaphragm 3B is projected inside the reflecting portion 5b of the optical path combining member 5. Thus, the scanning light traveling on and near the optical axis of the scanning optical path OP3 is reflected by the optical path combining member 5 and travels on and near the optical axis of the optical path OP4.

  The transmission part 5a is provided around the reflection part 5b, and transmits the return light from the eye E that is incident from the optical path OP4 so as to guide it to the photodetectors 16A and 16B (described later) of the detection system. The transmission part 5a may be formed of, for example, a light-transmitting material or may be formed as an opening. The return light from the eye E is mixed with noise light such as reflected light from the optical element and reflected light from the eye tissue, and the noise light travels on and near the optical axis of the optical path OP4. The size of the reflecting portion 5b can be designed so that at least a part of the noise light is sufficiently shielded. 3 represents a typical example of the contour of a region (a beam cross section of the return light) onto which the return light from the eye E is projected.

  Typically, the optical path synthesis member 5 may be a member created by forming a thin film or the like that functions as the reflection portion 5b on a transparent substrate made of glass, synthetic resin, or the like. In another example, the optical path combining member 5 may be a member created by combining a reflecting member that functions as the reflecting portion 5b and a translucent member that functions as the transmitting portion 5a. Note that these are examples, and the optical path combining member 5 may have an arbitrary configuration capable of combining the optical path of the projection system and the optical path of the detection system.

  As described above, the optical path combining member 5 includes the reflecting portion 5b that is larger than the beam size of the scanning light that has passed through the first diaphragm 3A (or the second diaphragm 3B). The reflection unit 5b causes the scanning light that has passed through the first diaphragm 3A (or the second diaphragm 3B) to enter the optical path OP4 toward the optical scanner 9. Furthermore, the optical path combining member 5 includes a transmission part 5a provided around the reflection part 5b. The transmission unit 5a causes part of the return light from the eye E to enter the optical path (detection optical path OP5) toward the first photodetector 16A (or the second photodetector 16B).

  In other words, the reflecting portion 5b of the optical path combining member 5 includes a region (region denoted by reference numeral R1 in FIG. 3) onto which the scanning light that has passed through the first diaphragm 3A (or the second diaphragm 3B) is projected, and this It is larger than the projection area (R1).

  Specifically, the optical path combining member 5 is provided obliquely with respect to each of the optical path of the projection system (scanning optical path OP3) and the optical path of the detection system (detection optical path OP5), and includes the reflection part 5b and the transmission part 5a. I have. More specifically, the reflection unit 5b reflects the scanning light that has passed through the first diaphragm 3A (or the second diaphragm 3B), enters the optical path OP4 toward the optical scanner 9, and returns from the eye E to be examined. Of the light, the portion projected onto the reflecting portion 5b is reflected in a direction different from the optical path (detection optical path OP5) toward the first photodetector 16A (or the second photodetector 16B). Furthermore, the transmission part 5a transmits the part projected to the transmission part 5a in the return light from the eye E, and passes the optical path (detection optical path) toward the first optical detector 16A (or the second optical detector 16B). The light is incident on OP5).

  As described above, in another embodiment, the optical path combining member that combines the optical path of the projection system and the optical path of the detection system is configured to transmit the scanning light and reflect the return light from the eye E. It's okay. In this case, for example, it is possible to use an optical path combining member in which the area indicated by reference numeral 5b in FIG. 2 is configured as a transmission part and the area indicated by reference numeral 5a is configured as a reflection part. Such an optical member is known as a perforated mirror used for synthesizing an illumination optical system and a photographing optical system in a general fundus camera.

  1 to 3, when a perforated mirror is used as the optical path combining member 5, the perforated mirror has a transmission portion larger than the beam size of the scanning light that has passed through the diaphragm member (first diaphragm 3 </ b> A, etc.). 5b. The transmission unit 5b causes the scanning light that has passed through the diaphragm member to enter the optical path OP4 toward the optical scanner 9. Further, the perforated mirror includes a reflecting portion 5a provided around the transmitting portion 5b. The reflection unit 5a causes part of the return light from the eye E to enter the optical path (detection optical path OP5) toward the photodetector (the first photodetector 16A and the like).

  In other words, the transmission part 5b of the perforated mirror includes a region (region denoted by reference numeral R1 in FIG. 3) onto which the scanning light that has passed through the diaphragm member is projected, and is larger than the projection region (R1).

  Specifically, the perforated mirror is provided obliquely with respect to each of the optical path of the projection system (scanning optical path OP3) and the optical path of the detection system (detection optical path OP5), and includes a transmission part 5b and a reflection part 5a. ing. More specifically, the transmission part 5b reflects the scanning light that has passed through the diaphragm member to enter the optical path OP4 toward the optical scanner 9, and is projected to the transmission part 5b out of the return light from the eye E to be examined. The transmitted portion is transmitted in a direction different from the optical path (detection optical path OP5) toward the photodetector. Further, the reflection unit 5a reflects the portion of the return light from the eye E to be projected onto the reflection unit 5a and makes it incident on the optical path (detection optical path OP5) toward the photodetector.

  The optical path combining member 5 (or perforated mirror) can be disposed at a position (or in the vicinity thereof) optically conjugate with the cornea of the eye E to be examined. Thereby, reflection from the cornea, which is representative noise light along with reflection from the objective lens 11, can be effectively removed.

  Scanning light (parallel light beam) incident on the optical path OP4 via the optical path combining member 5 (or perforated mirror) becomes convergent light by the lens 6, is reflected by the reflecting mirror 7, is refracted by the lens 8, and is optical scanner 9 Led to.

  The optical scanner 9 deflects the scanning light two-dimensionally. For example, the optical scanner 9 includes a first optical scanner that deflects light in the X direction and a second optical scanner that deflects light in the Y direction. Typically, one of the first optical scanner and the second optical scanner is a low-speed scanner (such as a galvanometer mirror), and the other is a high-speed scanner (such as a resonant mirror, a polygon mirror, or a MEMS mirror). In a state where the alignment is suitable, the optical scanner 9 (for example, the reflective surface of the first optical scanner, the reflective surface of the second optical scanner, or a predetermined position between the first optical scanner and the second optical scanner) is It is arranged at a position (or its vicinity) optically conjugate with the pupil of the optometry E. As a result, the scanning light can be swung around a point in the pupil of the eye E (or the vicinity thereof), and a wide range of the fundus oculi Ef can be scanned.

  Scanning light passing through the optical scanner 9 is refracted by the relay lens 10 and focused on the eye E by the objective lens 11. When the alignment is suitable, the scanning light is imaged on the surface of the fundus oculi Ef, for example. Further, by moving the objective lens 11 in the direction along the optical axis of the optical path OP4, the focus adjustment (and diopter correction) of the projection system and the detection system can be performed. A dedicated lens for performing focus adjustment can also be provided.

  The scanning light is reflected and scattered at the fundus oculi Ef. The light emitted from the eye E includes not only reflected light from the surface of the fundus oculi Ef but also scattered light from the fundus oculi Ef, reflected light from the crystalline lens, reflected light from the corneal surface, and the like. For example, a part of the scanning light reflected by the rear surface of the objective lens 11 (the surface on the relay lens 10 side) is further mixed into the light emitted from the eye E. Such return light travels in the optical path OP4 in the opposite direction to the scanning light, and is guided to the optical path combining member 5.

  A part of the return light projected on the optical path combining member 5 passes through the transmission part 5a and enters the detection optical path OP5. At this time, noise light (reflected light from the crystalline lens, cornea, objective lens 11, etc.) included on the optical axis of the optical path OP4 and in the vicinity thereof is projected on the reflecting portion 5b, and therefore does not enter the detection optical path OP5. . That is, noise light (at least a part) included in the return light from the eye E is removed by the optical path synthesis member 5.

  The return light incident on the detection optical path OP5 is projected onto the dichroic mirror (or half mirror or the like) 12. The dichroic mirror 12 divides the detection optical path OP5 into a first detection optical path OP6 and a second detection optical path OP7. When scanning the fundus oculi Ef with the scanning light from the first scanning optical path OP1, the return light passes through the dichroic mirror 12 and enters the first detection optical path OP6. On the other hand, when scanning the fundus oculi Ef with the scanning light from the second scanning optical path OP2, the return light is reflected by the dichroic mirror 12 and enters the second detection optical path OP7.

  The return light incident on the first detection optical path OP6 is refracted by the first condenser lens 14A and projected onto the first confocal stop 15A. In a state where the alignment is suitable, the first confocal stop 15A is disposed at a position (or in the vicinity thereof) optically conjugate with the fundus oculi Ef. The first confocal stop 15A acts to block at least part of noise light (fundus scattered light or the like) included in the return light and selectively allow reflected light from the surface of the fundus oculi Ef to pass through.

  The return light that has passed through the first confocal stop 15A is detected by the first photodetector 16A. The first photodetector 16A includes, for example, an avalanche photodiode or a photomultiplier tube.

  On the other hand, the return light incident on the second detection optical path OP7 is refracted by the second condenser lens 14B and projected onto the second confocal stop 15B. In a state where the alignment is suitable, the second confocal stop 15B is disposed at a position (or in the vicinity thereof) optically conjugate with the fundus oculi Ef. The second confocal stop 15B functions to block at least part of noise light (fundus scattered light or the like) included in the return light and selectively allow reflected light from the surface of the fundus oculi Ef to pass through.

  The return light that has passed through the second confocal stop 15B is detected by the second photodetector 16B. The second photodetector 16B includes, for example, an avalanche photodiode or a photomultiplier tube.

  In this example, the detection system includes an objective lens 11, a relay lens 10, an optical scanner 9, a lens 8, a reflection mirror 7, a lens 6, an optical path combining member 5, a dichroic mirror 12, and a first collection. It includes an optical lens 14A, a first confocal stop 15A, a first photodetector 16A, a second condenser lens 14B, a second confocal stop 15B, and a second photodetector 16B.

<Processing system>
A configuration example of a processing system of the ophthalmologic photographing apparatus according to the embodiment is shown in FIG. The processing system includes one or more processors for executing various types of data processing (signal processing, image processing, calculation, control, storage, etc.).

  The “processor” is, for example, a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), an ASIC (Application Specific Integrated Circuit), or a programmable logic device (for example, SPLD (Simple ProgramLD). Device), FPGA (Field Programmable Gate Array)) and the like. The processor implements the functions according to the embodiment by, for example, reading and executing a computer program stored in a storage circuit or a storage device.

  The processing system of the ophthalmologic photographing apparatus according to the embodiment is included in the optical system shown in FIG. 1, such as the first light source 1A, the second light source 1B, the optical scanner 9, the first photodetector 16A, and the second photodetector 16B. Contains part of the element. Further, the processing system includes a control unit 100, an image forming unit 110, a data processing unit 120, and a user interface unit 130.

<Control unit 100>
The control unit 100 includes a configuration for controlling each unit of the ophthalmologic photographing apparatus. The control unit 100 includes a main control unit 101 and a storage unit 102. The function of the main control unit 101 is realized by one or more processors. The storage unit 102 stores various data, various information, various computer programs, and the like. The storage unit 102 includes a semiconductor memory, a magnetic storage device, and the like.

  The processing executed by the ophthalmologic photographing apparatus is realized by cooperation between hardware resources (such as a processor) and software (such as a computer program). In addition, actuators are provided in at least some of the various mechanisms provided in the ophthalmologic photographing apparatus. The main control unit 101 sends a control signal to each actuator.

<Main control unit 101>
The main control unit 101 includes a processor, and generates and transmits various control signals. Thereby, each part of the ophthalmologic photographing apparatus is controlled. For example, the main control unit 101 controls the first light source 1A, the second light source 1B, the optical scanner 9, the first photodetector 16A, the second photodetector 16B, and the like.

  Control of the 1st light source 1A and the 2nd light source 1B includes lighting, light extinction, light quantity adjustment, etc. The control of the optical scanner 9 includes scanning position control, scanning range control, scanning pattern control, scanning speed control, and the like. Control of the first photodetector 16A and the second photodetector 16B includes exposure adjustment, gain adjustment, detection rate (detection repetition frequency) adjustment, and the like.

  Although illustration is omitted, the ophthalmologic photographing apparatus may include an optical system moving mechanism for moving the optical system in the X direction, the Y direction, and the Z direction. The control of the optical system moving mechanism is executed in alignment or the like.

  When performing SLO imaging, the main control unit 101 lights (flashes) the first light source 1A (or the second light source 1B) at a predetermined timing, and moves the optical scanner 9 according to a predetermined scanning pattern (for example, raster scan). Control.

<Storage unit 102>
The storage unit 102 stores information, data, computer programs, and the like used by the ophthalmologic photographing apparatus. Further, the storage unit 102 stores data acquired by the ophthalmologic photographing apparatus and data acquired from the outside.

<Image Forming Unit 110>
The image forming unit 110 forms an image of the fundus oculi Ef based on data collected using the optical system. More specifically, the image forming unit 110 includes the detection signal input from the first photodetector 16A (or the second photodetector 16B) and the pixel input from the control unit 100, as in the conventional SLO. An image is formed based on the position signal.

<Data processing unit 120>
The data processing unit 120 executes various data processing. As an example of data processing, there is processing for image data formed by the image forming unit 110 or another device. Examples of this processing include various types of image processing, image analysis processing, and diagnostic support processing such as image evaluation based on image data.

<User interface unit 130>
The user interface (UI) unit 130 has a function for exchanging information between the user and the ophthalmologic photographing apparatus. The user interface unit 130 includes a display device and an operation device (input device). The display device includes, for example, a liquid crystal display (LCD). The operation device includes various hardware keys and / or software keys. The control unit 100 receives the operation content for the operation device and outputs a control signal corresponding to the operation content to each unit. It is possible to integrally configure at least a part of the operation device and at least a part of the display device. A touch panel display is an example.

<Action and effect>
Several examples of the operation and effect of the ophthalmologic photographing apparatus according to the embodiment will be described.

  The ophthalmologic photographing apparatus according to the embodiment includes a projection system, a detection system, an optical path synthesis member, and an image forming unit. The projection unit projects the light output from the light source (for example, the first light source 1A or the second light source 1B) onto the fundus of the eye to be examined via the optical scanner (for example, the optical scanner 9) and the objective lens (for example, the objective lens 11). To do. The detection system guides the return light from the eye to be examined, which has been projected onto the fundus by the projection unit, to the photodetector via the objective lens (for example, the objective lens 11) and the optical scanner (for example, the optical scanner 9). The optical path synthesis member synthesizes the optical path of the projection system and the optical path of the detection system (for example, the optical path synthesis member 5 or the perforated mirror). The image forming unit forms a fundus image based on an output from a photodetector included in the detection system (for example, the image forming unit 110).

  Further, the projection system includes a diaphragm member (for example, the first diaphragm 3A or the second diaphragm 3B). The diaphragm member is disposed between the light source and the optical path combining member, and limits the beam size of the light output from the light source. In addition, the optical path combining member includes a first region and a second region. The first region is larger than the beam size of the light that has passed through the diaphragm member, and allows the light that has passed through the diaphragm member to enter the optical path toward the optical scanner. As a typical example of the first region, there are a reflection portion 5b of the optical path combining member 5 and a transmission portion (5b) of the perforated mirror. The second region is provided around the first region, and makes part of the return light from the eye to be examined enter the optical path toward the photodetector. As a typical example of the second region, there are a transmission portion 5a of the optical path combining member 5 and a reflection portion (5a) of the perforated mirror.

  In the embodiment, the first region (for example, the reflection portion 5b) of the optical path combining member includes a region where light that has passed through the diaphragm member (for example, the first diaphragm 3A) is projected. May be formed larger.

  In the embodiment, the optical path combining member (for example, the optical path combining member 5) may be provided obliquely with respect to each of the optical path of the projection system and the optical path of the detection system. Further, the first region of the optical path combining member may be a first reflection region (for example, the reflection portion 5b) that reflects light, and the second region is a first transmission region (for example, the transmission portion 5a) that transmits light. It may be.

  In the embodiment, the first reflection area (for example, the reflection portion 5b) may be configured to perform the following two actions: the first reflection area is light that has passed through the diaphragm member (for example, the first diaphragm 3A). The first reflection area reflects the portion of the return light from the eye to be projected onto the first reflection area to the photodetector (for example, the optical scanner 9 for example, the optical scanner 9). Reflects in a direction different from the optical path toward the first photodetector 16A). Furthermore, the first transmission region may be configured to transmit a portion of the return light from the eye to be examined, which is projected to the first transmission region, and enter the light path toward the photodetector.

  In the embodiment, the optical path combining member (for example, a perforated mirror) may be provided obliquely with respect to each of the optical path of the projection system and the optical path of the detection system. Further, the first region of the optical path combining member may be a second transmissive region (for example, the transmissive portion 5b) that transmits light, and the second region is a second reflective region (for example, the reflective portion 5a) that reflects light. It may be.

  In the embodiment, the second transmissive region (for example, the transmissive portion 5b) may be configured to perform the following two functions: the second transmissive region transmits light that has passed through the aperture member, and is an optical scanner. The second transmissive region transmits a portion of the return light from the eye to be projected to the second transmissive region in a direction different from the optical path toward the photodetector. Furthermore, the second reflection region may be configured to reflect a portion of the return light from the eye to be examined, which is projected to the second reflection region, and to enter an optical path toward the photodetector.

  According to any of the embodiments as described above, as apparent from the configurations of the aperture member and the optical path combining member, the position where the optical path of the projection system and the optical path of the detection system are combined (that is, the position of the optical path combining member). ), An interval (margin) is provided between the light projected on the eye to be examined and the return light from the eye to be examined guided to the photodetector. Therefore, noise light caused by the objective lens passing through a position off the optical axis can be effectively removed by the optical path synthesis member (particularly, the first region).

  In the embodiment, the optical path synthesis member (for example, the optical path synthesis member 5 or the perforated mirror) may be disposed at a position (or in the vicinity thereof) optically conjugate with the cornea of the eye to be examined. With this configuration, noise light caused by the cornea of the eye to be examined can be effectively removed by the optical path synthesis member (particularly, the first region).

  The embodiment described above is merely an example for carrying out the present invention. A person who intends to implement the present invention can make arbitrary modifications, omissions, additions and the like within the scope of the present invention.

DESCRIPTION OF SYMBOLS 1A 1st light source 1B 2nd light source 3A 1st aperture stop 3B 2nd aperture stop 5 Optical path synthetic | combination member 5a Transmission part 5b Reflection part 9 Optical scanner 11 Objective lens 16A 1st photodetector 16B 2nd photodetector 110 Image formation part

Claims (7)

A projection system for projecting light output from the light source to the fundus of the eye to be examined via an optical scanner and an objective lens;
A detection system for guiding the return light of the light from the eye to be examined to a photodetector via the objective lens and the optical scanner;
An optical path combining member that combines the optical path of the projection system and the optical path of the detection system;
An image forming unit that forms an image of the fundus oculi based on an output from the photodetector;
The projection system includes a diaphragm member that is disposed between the light source and the optical path combining member and limits a beam size of light output from the light source,
The optical path combining member is
A first region that is larger than the beam size of the light that has passed through the aperture member, and that makes the light that has passed through the aperture member enter an optical path toward the optical scanner;
An ophthalmologic photographing apparatus comprising: a second region provided around the first region and allowing a part of the return light to enter an optical path toward the photodetector. The ophthalmologic photographing apparatus according to claim 1, wherein the first region of the optical path combining member includes a region where light that has passed through the diaphragm member is projected, and is larger than the projection region. The optical path combining member is provided obliquely with respect to each of the optical path of the projection system and the optical path of the detection system,
The first region is a first reflection region that reflects light;
The ophthalmologic photographing apparatus according to claim 1, wherein the second region is a first transmission region that transmits light. The first reflection region reflects light that has passed through the diaphragm member to enter the optical path toward the optical scanner, and a portion of the return light that is projected onto the optical path is different from the optical path toward the photodetector. Reflected towards the direction,
The ophthalmic imaging apparatus according to claim 3, wherein the first transmission region transmits a portion of the return light projected to the light and enters the optical path toward the photodetector. The optical path combining member is provided obliquely with respect to each of the optical path of the projection system and the optical path of the detection system,
The first region is a second transmission region that transmits light;
The ophthalmologic photographing apparatus according to claim 1, wherein the second region is a second reflection region that reflects light. The second transmission region transmits light that has passed through the aperture member and enters the light path toward the optical scanner, and the projected portion of the return light is different from the light path toward the photodetector. Let it pass in the direction,
The ophthalmologic photographing apparatus according to claim 5, wherein the second reflection region reflects a portion of the return light projected onto the light path and enters the light path toward the photodetector. The ophthalmic imaging apparatus according to claim 1, wherein the optical path combining member is disposed at a position optically conjugate with the cornea of the eye to be examined.