WO2023188612A1 - Fundus observation device - Google Patents

Abstract

This fundus observation device includes an optical system, two concave mirrors, and a holding member. The optical system projects light from a light source onto the fundus of an eye being examined, and receives return light from the fundus. The two concave mirrors each have a concave reflective surface, and guide light from the optical system to the fundus and guide the return light to the optical system. The holding member holds the two concave mirrors. At least one of the two concave mirrors has a flange having one of a fixing part or a fixed part formed thereon. The other of a fixing part or a fixed part is formed on the holding member. The fundus observation device is configured so that the flange is held by the holding member in a state in which the fixed part is fixed by the fixing part.

Description

Fundus observation device

The present invention relates to a fundus observation device.

Fundus observation devices for screening and treating eye diseases are required to be able to easily observe and photograph the fundus of the eye to be examined with a wide field of view. Specifically, there is a demand for a device that can observe the fundus of the eye to be examined at a wide angle of view of more than 80 degrees in one shot. A scanning laser ophthalmoscope (SLO) is known as such a fundus observation device. The SLO is a device that scans the fundus with light and forms an image of the fundus by detecting the returned light from the fundus with a light receiving device.

Various techniques regarding such fundus observation devices have been proposed.

For example, Patent Document 1 discloses a scanning ophthalmoscope capable of scanning the retina at a wide angle by performing two-dimensional parallel light scanning using two ellipsoidal mirrors and a plane mirror, which are moved by a scanning moving means. ing.

Special Publication No. 2009-543585

When observing (photographing) the fundus at a wide angle, it is necessary to allow light deflected over a wide range of deflection angles to enter the eye through the pupil. This means that the accuracy of an optical system such as an ellipsoidal mirror has a greater influence on the accuracy of fundus observation.

However, with conventional technology, even if the optical member itself, such as an ellipsoidal mirror, is highly accurate, the accuracy of fundus observation may decrease due to the adjustment accuracy such as positioning of the optical member, or Adjustment work such as positioning may become complicated. Therefore, a new technique for easily adjusting optical members with high precision is required.

The present invention has been made in view of these circumstances, and one of its purposes is to provide a new technique for easily adjusting optical members with high precision.

One aspect of the embodiment includes an optical system that projects light from a light source onto the fundus of the eye to be examined and receives return light from the fundus, each of which has a concave reflective surface, It includes two concave mirrors that guide the light to the fundus of the eye and guide the returned light to the optical system, and a holding member that holds the two concave mirrors, and at least one of the two concave mirrors has a fixing part and a cover. The holding member has a flange formed with one of the fixed parts, the other of the fixed part and the fixed part is formed on the holding member, and the flange is fixed with the fixed part fixed by the fixed part. The fundus observation device is configured to be held by the holding member.

According to the present invention, it is possible to provide a new technique for easily adjusting optical members with high precision.

FIG. 1 is a schematic diagram showing an example of the configuration of an optical system of the fundus observation device according to the first embodiment. FIG. 2 is a schematic diagram showing an example of the configuration of a first ellipsoidal mirror according to the first embodiment. FIG. 2 is a schematic diagram showing an example of the configuration of a first ellipsoidal mirror according to the first embodiment. FIG. 2 is a schematic diagram showing an example of the configuration of a first ellipsoidal mirror according to the first embodiment. FIG. 2 is a schematic diagram showing an example of the configuration of a first ellipsoidal mirror according to the first embodiment. FIG. 2 is a schematic diagram showing an example of the configuration of a first ellipsoidal mirror according to the first embodiment. FIG. 3 is a schematic diagram showing an example of the configuration of a second ellipsoidal mirror according to the first embodiment. FIG. 3 is a schematic diagram showing an example of the configuration of a second ellipsoidal mirror according to the first embodiment. FIG. 3 is a schematic diagram showing an example of the configuration of a second ellipsoidal mirror according to the first embodiment. FIG. 3 is a schematic diagram showing an example of the configuration of a second ellipsoidal mirror according to the first embodiment. FIG. 3 is a schematic diagram showing an example of the configuration of a second ellipsoidal mirror according to the first embodiment. FIG. 2 is a schematic diagram showing an example of the configuration of a first ellipsoidal mirror and a second ellipsoidal mirror according to the first embodiment. FIG. 2 is a schematic diagram showing an example of the configuration of a first ellipsoidal mirror and a second ellipsoidal mirror according to the first embodiment. FIG. 2 is a schematic diagram showing an example of the configuration of a first ellipsoidal mirror and a second ellipsoidal mirror according to the first embodiment. FIG. 2 is a schematic diagram showing an example of the configuration of a first ellipsoidal mirror and a second ellipsoidal mirror according to the first embodiment. FIG. 2 is a schematic diagram showing an example of the configuration of a first ellipsoidal mirror and a second ellipsoidal mirror according to the first embodiment. FIG. 2 is a schematic diagram showing an example of the configuration of a first ellipsoidal mirror and a second ellipsoidal mirror according to a comparative example of the first embodiment. FIG. 2 is a schematic diagram showing an example of the configuration of a first ellipsoidal mirror and a second ellipsoidal mirror according to a comparative example of the first embodiment. FIG. 2 is a schematic diagram showing an example of the configuration of a first ellipsoidal mirror and a second ellipsoidal mirror according to the first embodiment. FIG. 2 is a schematic diagram showing an example of the configuration of a first ellipsoidal mirror and a second ellipsoidal mirror according to the first embodiment. FIG. 2 is a schematic diagram showing an example of the configuration of a processing system of the fundus observation device according to the first embodiment. It is a flow chart showing an example of operation of the fundus observation device according to the first embodiment. It is a schematic diagram showing an example of composition of an optical system of a fundus oculi observation device concerning a 2nd embodiment. It is a schematic diagram showing an example of composition of an optical system of a fundus oculi observation device concerning a 2nd embodiment. It is a schematic diagram showing an example of composition of a processing system of a fundus oculi observation device concerning a 2nd embodiment. It is a flow chart showing an example of operation of the fundus observation device according to the second embodiment. FIG. 7 is a schematic diagram for explaining the operation of the fundus observation device according to the second embodiment. It is a schematic diagram showing an example of composition of an optical system of a fundus oculi observation device concerning a 3rd embodiment. It is a schematic diagram showing an example of composition of an optical system of a fundus oculi observation device concerning a 4th embodiment. It is a schematic diagram showing an example of composition of an optical system of a fundus observation device concerning a 5th embodiment.

An example of an embodiment of a fundus observation device according to the present invention will be described in detail with reference to the drawings. Note that the contents of the documents cited in this specification and any known technology can be incorporated into the following embodiments.

In this specification, a "processor" refers to, for example, a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), an ASIC (Application Specific Integrated C circuit), programmable logic devices (for example, SPLD (Simple Programmable Logic Device), CPLD (Complex It means a circuit such as a programmable logic device (FPGA) or a field programmable gate array (FPGA). The processor realizes the functions according to the embodiment by, for example, reading and executing a program stored in a storage circuit or a storage device.

The fundus observation device according to the embodiment includes an optical system and two concave mirrors having concave reflective surfaces, and guides light from the optical system to the fundus of the eye to be examined and returns light from the fundus to the optical system. . The optical system projects light from a light source onto the fundus of the eye via two concave mirrors, and receives light returned from the fundus of the eye via two concave mirrors. The fundus observation device includes a holding member that holds two concave mirrors. At least one of the two concave mirrors has a flange in which one of a fixed part and a fixed part is formed, and the other of the fixed part and a fixed part is formed in the holding member. The fundus observation device is configured such that the flange is held by the holding member while the part to be fixed is fixed by the fixing part.

Thereby, the holding member can hold the concave mirror in a state where the fixed part is fixed by the fixing part so that the positional relationship between the concave mirror and the holding member is a predetermined positional relationship. As a result, it becomes possible to easily realize highly precisely designed optical measurement conditions and improve the accuracy of fundus observation at low cost. In particular, by manufacturing optical members such as concave mirrors using high-precision processing technology, it is possible to suppress deterioration in optical measurement accuracy due to alignment accuracy.

The optical system includes an imaging optical system, an optical coherence tomography (OCT) optical system, an SLO optical system, or a combination of two or more of these. The photographing optical system illuminates the fundus with light from a light source and receives return light from the fundus to form a fundus image based on the light reception result obtained. The OCT optical system splits light from a light source into measurement light and reference light, scans the fundus with the measurement light, and detects interference light between the measurement light returning from the fundus and the reference light. A fundus image (tomographic image, frontal image) is formed based on the detection results of the interference light. The SLO optical system scans the fundus with light from a light source and forms a fundus image based on the light reception result obtained by receiving light returned from the fundus.

In some embodiments, the two concave mirrors are arranged such that their reflective surfaces face each other, and the light deflected by the deflection member is reflected by one concave mirror, and the reflected light is reflected by the other concave mirror. The eye is configured to be guided to the eye to be examined. In some embodiments, an optical scanner or reflective mirror is placed between two concave mirrors, and the light reflected by one concave mirror is deflected by the optical scanner or reflective mirror and reflected by the other concave mirror to the subject's eye. Configured to lead.

A concave mirror is an ellipsoidal mirror whose reflecting surface forms part of an ellipsoid (ellipsoidal surface), a parabolic mirror whose reflecting surface forms part of a paraboloid, or a reflecting surface forms part of a free-form surface. It may be a free-form mirror. The two concave mirrors may be a combination of the same type of concave mirrors or a combination of different types of concave mirrors. In some embodiments, the two concave mirrors are two ellipsoidal mirrors. In some embodiments, the two concave mirrors are an ellipsoidal mirror and a freeform mirror.

The fixing part fixes the positional relationship with the fixed part by fitting, hooking, latching, crimp, connecting, or the like. In some embodiments, one of the fixed part and the fixed part is a fitting member, and the other is a fitted member. In some embodiments, one of the fixed part and the fixed part is a locking member, and the other is a locked member. In some embodiments, the fixing part is a recess or a hole, and the fixed part is a convex part (protrusion).

A fundus observation device in which the holding member holds two concave mirrors as described above, for example, illuminates the fundus of the subject's eye with illumination light having a slit-shaped (line-shaped) cross-sectional light beam shape, and It is possible for the two-dimensional image sensor to receive the return light of the illumination light from the fundus in a movable light-receiving range (focal plane, virtual aperture range) at a position that is substantially conjugate to the eye. At this time, the optical path of the illumination light and the optical path of the return light are combined ( separation) and deflecting the illumination light in synchronization with the movement of the light-receiving range (focal plane), it is possible to scan the fundus with the illumination light. In some embodiments, the optical path coupling portion of the optical path of the illumination light and the optical path of the return light in the deflection member is arranged at a position that is optically approximately conjugate with the pupil of the eye to be examined. In some embodiments, the deflection member is a hole mirror.

This is simple, low-cost, avoids deterioration of optical measurement conditions due to assembly (installation) accuracy of optical components, and allows measurement of 80 degrees with just the optical system that scans in the width direction of the illumination light line. It becomes possible to easily arrange a shared optical system for a wide-angle illumination light optical path and a return light optical path by securing a photographing angle of view exceeding that of the conventional one.

In some embodiments, the fundus observation device further includes an optical scanner, irradiates the subject's eye with measurement light deflected by the optical scanner, and detects interference light between the return light of the measurement light and the reference light. Contains OCT optics to perform the scan. In this case, the optical path of the return light of the slit-shaped (line-shaped) illumination light and the optical path of the OCT optical system are coupled by the optical path coupling/separating member disposed between the deflection member and the two-dimensional image sensor. That is, by optically coupling the OCT optical system on the transmission side of the deflection member (through the hole of the hole mirror), the optical path of the return light of the illumination light can be separated from the shared optical system at low cost. In addition, it is possible to perform OCT measurement (OCT photography) at any position on the fundus observed at a large wide angle without having to share the optical scanner for OCT scanning and the optical scanner for deflecting illumination light. become.

Hereinafter, a case will be described in which the fundus observation device according to the embodiment acquires an image of the fundus of the eye to be examined using two ellipsoidal mirrors (concave mirrors in a broad sense) arranged so as to share one focal position. do.

Hereinafter, for convenience of explanation, the scan center direction of the light projected onto the fundus will be referred to as the z direction (optical axis direction of the optical system), the vertical direction (vertical direction) orthogonal to the z direction will be referred to as the y direction, and the direction perpendicular to the z direction will be referred to as the y direction. Let the left-right direction (horizontal direction) be the x direction.

<First embodiment>
<Configuration>
FIG. 1 shows a configuration example of an optical system of a fundus observation apparatus according to a first embodiment. In FIG. 1, a position that is optically approximately conjugate with the fundus Ef of the eye E to be examined is illustrated as a fundus conjugate position P, and a position that is approximately optically conjugate with the pupil (iris) of the eye E to be examined is a pupil conjugate position ( The iris conjugate position) is shown as Q.

The fundus observation device 1 according to the first embodiment includes a slit projection optical system 10, a slit light receiving optical system 20, a hole mirror 30 as a deflection member having a scanning mechanism, a first ellipsoidal mirror 40, and a second ellipsoidal mirror 40. A surface mirror 50 is included.

(Slit projection optical system 10)
The slit projection optical system 10 generates slit-shaped illumination light (illumination light with a line-shaped cross-sectional shape of the beam) and projects the generated illumination light onto the hole mirror 30 . The slit projection optical system 10 includes an illumination light source 11, an iris diaphragm 12, a slit 13, and a projection lens 14.

The illumination light source 11 includes a visible light source that generates light in the visible region. For example, the illumination light source 11 generates light having a center wavelength in the wavelength range of 420 nm to 700 nm. Such an illumination light source 11 includes, for example, an LED (Light Emitting Diode), an LD (Laser Diode), a halogen lamp, or a xenon lamp. In some embodiments, the illumination light source 11 includes a white light source or a light source capable of outputting light of each RGB color component. In some embodiments, the illumination light source 11 includes a light source that can switch and output light in the infrared region or light in the visible region. The illumination light source 11 is arranged at a position optically non-conjugate with each of the fundus Ef and pupil (iris) of the eye E to be examined.

The iris diaphragm 12 (specifically, the opening described below) can be placed at the pupil conjugate position Q. The iris diaphragm 12 has one or more openings formed at positions away from the optical axis of the optical path of the light output from the illumination light source 11. The opening formed in the iris diaphragm 12 defines the incident position (incident shape) of the illumination light on the iris of the eye E to be examined. For example, the iris diaphragm 12 has openings formed at symmetrical positions with respect to the optical axis. As a result, when the pupil center of the eye E to be examined is placed on the optical axis of the optical path of the illumination light, the illumination light is emitted from a position eccentric from the pupil center (specifically, a point symmetrical position with the pupil center as the center). It becomes possible to introduce it into the eye.

Furthermore, by changing the relative position between the illumination light source 11 and the opening formed in the iris diaphragm 12, it is possible to change the light amount distribution of light passing through the opening formed in the iris diaphragm 12. be.

The slit 13 (specifically, the opening described below) can be placed at a conjugate position P on the fundus. The opening formed in the slit 13 defines the shape of the irradiation area (irradiation pattern shape) of the illumination light on the fundus Ef of the eye E to be examined.

The slit 13 is movable in the optical axis direction of the slit projection optical system 10 by a moving mechanism (not shown). The moving mechanism moves the slit 13 in the optical axis direction under control from a control section, which will be described later. Thereby, the position of the slit 13 can be moved according to the condition of the eye E to be examined (specifically, the refractive power and the shape of the fundus Ef).

In some embodiments, the slit 13 is configured such that at least one of the position and shape of the opening can be changed depending on the condition of the eye E to be examined without being moved in the optical axis direction. Such a function of the slit 13 is realized by, for example, a liquid crystal shutter.

The light from the illumination light source 11 that has passed through the opening formed in the iris diaphragm 12 passes through the opening formed in the slit 13, is transmitted through the projection lens 14, and is output as slit-shaped illumination light. The slit-shaped illumination light output from the slit projection optical system 10 is guided to the hole mirror 30.

In some embodiments, the slit projection optical system 10 includes a projector equipped with a light source, and the projector outputs slit-shaped illumination light. Projectors include LCD (Liquid Crystal Display) projectors using a transmissive liquid crystal panel, LCOS (Liquid Crystal On Silicon) projectors using a reflective liquid crystal panel, and DMD (Digital Mir) projectors. DLP ( There are digital light processing (registered trademark) type projectors and the like.

(hole mirror 30)
The hole mirror 30 (specifically, the deflection surface described below) can be placed at the pupil conjugate position Q. The hole mirror 30 has a deflection surface whose direction (deflection direction) can be changed, and functions as a uniaxial optical scanner that guides the illumination light from the slit projection optical system 10 to the reflection surface of a first ellipsoidal mirror 40, which will be described later. do. A hole is formed in the deflection surface so that the optical axis of a slit light-receiving optical system 20 (described later) passes therethrough. That is, the hole mirror 30 has a structure in which the return light of the illumination light is transmitted (passes) through the center, and the illumination light is reflected at the periphery of the center.

The hole mirror 30 is arranged in a direction (slit width direction, lateral direction of the irradiation area) perpendicular to the slit direction of the irradiation area (the direction in which the slit extends, the longitudinal direction of the irradiation area) at the irradiation site of the illumination light in the eye E. The illumination light is deflected by changing the direction of the deflection plane so as to move sequentially. The hole mirror 30 is configured to be able to change the deflection direction of the illumination light under control from a control section that will be described later.

The illumination light from the slit projection optical system 10 is deflected by a deflection surface around the hole and guided to the reflection surface of the first ellipsoidal mirror 40. The return light of the illumination light from the eye E to be examined passes through the hole formed in the hole mirror 30 via the reflective surface of the first ellipsoidal mirror 40, and is guided to the slit light receiving optical system 20.

In some embodiments, the hole mirror 30 functions as a biaxial optical scanner that guides the illumination light from the slit projection optical system 10 to the reflective surface of the first ellipsoidal mirror 40.

In some embodiments, the hole mirror 30 is configured to transmit the wavelength component (or polarization component) of the return light of the illumination light. In this case, the return light of the illumination light from the eye E to be examined passes through the hole mirror 30 via the reflective surface of the first ellipsoidal mirror 40 and is guided to the slit light receiving optical system 20.

(Slit light receiving optical system 20)
The slit light receiving optical system 20 receives the return light of the illumination light from the eye E that has passed through the hole of the hole mirror 30. The slit light receiving optical system 20 includes an image sensor 21 and an imaging lens 22.

The image sensor 21 realizes the function of a two-dimensional image sensor as a pixelated light receiver. The light receiving surface (detection surface, imaging surface) of the image sensor 21 can be placed at a fundus conjugate position P. The image sensor 21 can set a movable light-receiving range (virtual aperture range, focal plane) at the fundus conjugate position P.

For example, the light reception result by the image sensor 21 is captured and read out using a rolling shutter method. In some embodiments, a control unit, which will be described later, controls the reading of light reception results by controlling the image sensor 21. In some embodiments, the image sensor 21 can automatically output light reception results for a predetermined line along with information indicating the light reception position.

Such an image sensor 21 includes, for example, a CMOS (complementary metal oxide semiconductor) image sensor. In this case, the image sensor 21 includes a plurality of pixels (light receiving elements) arranged in a row direction and a plurality of pixels arranged in a column direction. Specifically, the image sensor 21 includes a plurality of pixels arranged two-dimensionally, a plurality of vertical signal lines, and a horizontal signal line. Each pixel includes a photodiode (light receiving element) and a capacitor. A plurality of vertical signal lines are provided for each pixel group in a column direction (vertical direction) orthogonal to a row direction (horizontal direction). Each vertical signal line is selectively electrically connected to a pixel group in which charges corresponding to light reception results are accumulated. The horizontal signal line is selectively electrically connected to the plurality of vertical signal lines. Each pixel accumulates charges corresponding to the result of receiving the returned light, and the accumulated charges are sequentially read out, for example, for each pixel group in the row direction. For example, for each line in the row direction, a voltage corresponding to the charge accumulated in each pixel is supplied to the vertical signal line. The plurality of vertical signal lines are selectively electrically connected to the horizontal signal line. By sequentially performing the readout operation for each line in the row direction in the vertical direction, it is possible to read out the light reception results of a plurality of pixels arranged two-dimensionally.

By capturing (reading) the light reception results of the returned light to such an image sensor 21 using a rolling shutter method, a light reception image corresponding to a desired virtual aperture shape extending in the row direction is acquired. Such control is disclosed in, for example, US Pat. No. 7,831,106 or US Pat. No. 8,237,835.

The imaging lens 22 forms an image of the return light of the illumination light that has passed through the hole formed in the hole mirror 30 (or the return light of the illumination light that has passed through the hole mirror 30) on the light receiving surface of the image sensor 21.

(First ellipsoidal mirror 40)
The reflective surface (first reflective surface) of the first ellipsoidal mirror 40 is an ellipsoid (more specifically, a part of the ellipsoid). The first ellipsoidal mirror 40 is an example of a concave mirror.

The first ellipsoidal mirror 40 has two optically conjugate focal points (first focal point F1 and second focal point F2). The hole mirror 30 (the deflection surface of the hole mirror 30) is arranged at or near the first focal point F1 of the first ellipsoidal mirror 40. In some embodiments, the hole mirror 30 is arranged at or near a position optically conjugate with the first focal point F1 (conjugate position of the first focal point F1).

(Second ellipsoidal mirror 50)
The reflective surface (second reflective surface) of the second ellipsoidal mirror 50 is an ellipsoid (more specifically, a part of the ellipsoid). The second ellipsoidal mirror 50 is an example of a concave mirror.

The second ellipsoidal mirror 50 has two optically conjugate focal points (a first focal point F3 and a second focal point F4). The second ellipsoidal mirror 50 is arranged so that the first focal point F3 substantially coincides with the second focal point F2 of the first ellipsoidal mirror 40. In some embodiments, the second ellipsoidal mirror 50 is located at or near a position where the first focal point F3 is optically conjugate with the second focal point F2 of the first ellipsoidal mirror 40 (conjugate position of the second focal point F2). It is arranged so that it roughly matches. The eye E to be examined is placed at the second focal point F4 of the second ellipsoidal mirror 50. That is, the second ellipsoidal mirror 50 is arranged so that the second focal point F4 substantially coincides with the position of the eye to be examined where the eye to be examined E is placed.

In this way, it is not necessary to arrange the scanning optical member at the second focal point F2 (first focal point F3) between the first ellipsoidal mirror 40 and the second ellipsoidal mirror 50. , horizontal direction). For example, in the configuration described in Patent Document 1, since a deflection member that scans the illumination light in the horizontal direction is provided, the shooting angle of view is theoretically up to 180 degrees (in reality, up to about 150 degrees). can be ensured. On the other hand, according to the embodiment, since there is no need for a deflection member for scanning in the horizontal direction, it becomes possible to take pictures up to an angle of view exceeding 180 degrees (the cornea of the human eye is smaller than the pupil). Because it is placed in a position that projects forward, it is possible to observe a range exceeding 180 degrees with an effect similar to a fisheye lens.)

The first ellipsoidal mirror 40 and the second ellipsoidal mirror 50 are an example of "two concave mirrors" according to the embodiment. By being held by the holding member as described below, the second ellipsoidal mirror 50 can easily and at low cost have its first focal point F3 substantially coincident with the second focal point F2 of the first ellipsoidal mirror 40. It is possible to arrange it as follows.

FIGS. 2A to 2E schematically show an example of a holding structure for the first ellipsoidal mirror 40. In FIGS. 2A to 2E, parts similar to those in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted as appropriate.

The holding members according to the embodiment include a first holding member 41 that holds the first ellipsoidal mirror 40 (see FIGS. 2A to 2D), and a second holding member 51 that holds the second ellipsoidal mirror 50 (see FIGS. 3A to 2D). (see FIG. 3D), and is configured to be able to hold the second holding member 51 with respect to the first holding member 41.

The first ellipsoidal mirror 40 is formed, for example, by electroforming. Electroforming is a method of faithfully replicating the shape of a matrix at the nano level by electrochemically depositing metal ions in an electrolyte onto the surface of the matrix. This makes it possible to form the first ellipsoidal mirror 40 having a very precise shape.

Both ends of the first ellipsoidal mirror 40 in the long axis direction (predetermined first direction) have a shape cut along a plane perpendicular to the long axis direction. This makes it possible to reduce the weight and size of the first ellipsoidal mirror 40 while ensuring the size of the reflecting surface of the first ellipsoidal mirror 40 necessary for wide-angle fundus observation.

2A to 2C are schematic perspective views of the first holding member 41 that holds the first ellipsoidal mirror 40. FIG. 2A shows an example of how the first ellipsoidal mirror 40 is attached to the first holding member 41. FIG. 2B shows an example of the first ellipsoidal mirror 40 held by the first holding member 41 when viewed from the reflective surface side. FIG. 2C represents an example of the first ellipsoidal mirror 40 held by the first holding member 41 when viewed from the opposite side of the reflective surface.

As shown in FIGS. 2A to 2C, a flange (first flange) is formed at the peripheral edge of the first ellipsoidal mirror 40 (reflection surface). At least one protrusion is formed on the flange. The protrusion is an example of a protrusion. In this embodiment, protrusions 40A and 40B are formed on the flange at positions facing each other with a reflective surface interposed therebetween. For example, the protrusions 40A and 40B are formed at positions that are symmetrical with respect to a projection line obtained by projecting the long axis of the reflecting surface (an axis connecting the two focal points of the ellipsoid) onto the surface of the flange. That is, the protrusions 40A, 40B are formed at positions where the straight line connecting the protrusions 40A, 40B is perpendicular to the projection line. In the first holding member 41, the reflective surface of the first ellipsoidal mirror 40 held on the holding surface is exposed on the surface opposite to the holding surface, and the light incident from the surface opposite to the holding surface is directed to the reflective surface. The aperture is formed so that the light is reflected by the beam and exits from the surface opposite to the holding surface.

Further, the first holding member 41 is formed with holes 41A and 41B into which the protrusions 40A and 40B of the first ellipsoidal mirror 40 are inserted. Holes 41A and 41B are examples of recesses. The position of the first ellipsoidal mirror 40 with respect to the first holding member 41 is determined by inserting the projections 40A and 40B into the holes 41A and 41B.

FIG. 2D represents a schematic plan view of the first holding member 41 that holds the first ellipsoidal mirror 40 when viewed from the reflective surface side.

When the protrusion 40A is inserted into the hole 41A, the lower side (second focal point side) side surface 40Aa of the protrusion 40A abuts the lower side surface 41Aa of the hole 41A, and the protrusion intersects with the side surface 40Aa. A side surface 40Ab of the portion 40A on the reflective surface side contacts a side surface 41Ab on the opening side of the hole portion 41A. At the same time, the lower side surface 40Ba of the protrusion 40B abuts the lower side surface 41Ba of the hole 41B, and the reflective surface side side surface 40Bb of the protrusion 40B, which intersects with the side surface 40Ba, contacts the opening side of the hole 41B. It comes into contact with the side surface 41Bb.

Thereby, the position of the first ellipsoidal mirror 40 in the major axis direction and the minor axis direction can be easily and uniquely determined with respect to the first holding member 41.

In some embodiments, the upper side surface 40Ac of the protrusion 40A (first focal point side) is in contact with the upper side surface 41Ac of the hole 41A, and the upper side surface 40Bc of the protrusion 40B is in contact with the hole 41A. It is configured to abut on the upper side surface 41Bc of 41B.

The first holding member 41 holds the flange in a state where the protrusions 40A, 40B are inserted into the holes 41A, 41B and positioned, and the protrusions 40A, 40B are fixed by the holes 41A, 41B. configured to do so. For example, with the projections 40A and 40B fixed by being inserted into the holes 41A and 41B, the flange is fixed to the first holding member 41 by screwing, pinning, crimping, welding, caulking, etc. be done.

FIG. 2E shows a schematic plan view and side view of the first ellipsoidal mirror 40. Note that in FIG. 2E, for convenience of explanation, the plan view represents a view seen from the reflective surface side.

Both the first focal point F1 and the second focal point F2 of the first ellipsoidal mirror 40 are arranged at positions farther from the concave reflecting surface than the flange surface. In FIG. 2E, both the short-axis distance between the reflective surface and the first focal point F1 and the short-axis distance between the reflective surface and the second focal point F2 are the same as the distance between the reflective surface and the flange surface. longer than the distance in the minor axis direction between

The protrusions 40A and 40B are arranged near the second focal point F2 of the two focal points of the first ellipsoidal mirror 40. Specifically, as shown in FIG. 2E, on the surface of the flange formed on the first ellipsoidal mirror 40, the first projection point of the second focal point F2 of the first ellipsoidal mirror 40 (the second point on the surface of the flange) The straight line connecting the projection point of the focal point F2) and the second projection point of the first focal point F1 (the projection point of the first focal point F1 on the flange surface) is orthogonal to the straight line connecting the first projection point and the protrusion 40A. A protrusion 40A is formed at the position. Similarly, on the surface of the flange formed on the first ellipsoidal mirror 40, a straight line connecting the first projection point of the second focal point F2 of the first ellipsoidal mirror 40 and the second projection point of the first focal point F1; The protrusion 40B is formed at a position where the straight line connecting the first projection point and the protrusion 40B intersects at right angles.

Thereby, the position of the second focal point F2 of the first ellipsoidal mirror 40 held by the first holding member 41 (which is also the position of the first focal point F3 of the second ellipsoidal mirror 50) can be easily and highly accurately determined. Can be set.

FIGS. 3A to 3E schematically show an example of a holding structure for the second ellipsoidal mirror 50. In FIGS. 3A to 3E, parts similar to those in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted as appropriate.

The second ellipsoidal mirror 50 is formed, for example, by electroforming, similar to the first ellipsoidal mirror 40. This makes it possible to form the second ellipsoidal mirror 50 having a very precise shape.

Both ends of the second ellipsoidal mirror 50 in the long axis direction (predetermined first direction) have a shape cut by a plane intersecting the long axis direction. This makes it possible to reduce the weight and size of the second ellipsoidal mirror 50 while ensuring the size of the reflecting surface of the second ellipsoidal mirror 50 necessary for wide-angle fundus observation. In particular, by cutting the lower side, it is possible to avoid interference between the second ellipsoidal mirror 50 and the mouth or jaw of the subject to be observed.

3A to 3C represent schematic perspective views of the second holding member 51 that holds the second ellipsoidal mirror 50. FIG. 3A shows an example of how the second ellipsoidal mirror 50 is attached to the second holding member 51. FIG. 3B represents an example of the second ellipsoidal mirror 50 held by the second holding member 51 when viewed from the reflective surface side. FIG. 3C represents an example of the second ellipsoidal mirror 50 held by the second holding member 51 when viewed from the opposite side of the reflective surface.

As shown in FIGS. 3A to 3C, a flange (second flange) is formed at the peripheral edge of the second ellipsoidal mirror 50 (reflecting surface). At least one protrusion is formed on the flange. The protrusion is an example of a protrusion. In this embodiment, protrusions 50A and 50B are formed on the flange at positions facing each other with a reflective surface interposed therebetween. For example, the protrusions 50A and 50B are formed at positions that are symmetrical with respect to a projection line obtained by projecting the long axis of the reflecting surface (the axis connecting the two focal points of the ellipsoid) onto the surface of the flange. That is, the protrusions 50A, 50B are formed at positions where a straight line connecting the protrusions 50A, 50B is perpendicular to the projection line. In the second holding member 51, the reflective surface of the second ellipsoidal mirror 50 held on the holding surface is exposed on the surface opposite to the holding surface, and the light incident from the surface opposite to the holding surface is directed to the reflective surface. The aperture is formed so that the light is reflected by the beam and exits from the surface opposite to the holding surface.

Further, the second holding member 51 is formed with holes 51A and 51B into which the protrusions 50A and 50B of the second ellipsoidal mirror 50 are inserted. Holes 51A and 51B are examples of recesses. By inserting the projections 50A and 50B into the holes 51A and 51B, the position of the second ellipsoidal mirror 50 with respect to the second holding member 51 is determined.

FIG. 3D represents a schematic plan view of the second holding member 51 that holds the second ellipsoidal mirror 50 when viewed from the reflective surface side.

When the protrusion 50A is inserted into the hole 51A, the lower side (second focal point side) side surface 50Aa of the protrusion 50A abuts the lower side surface 51Aa of the hole 51A, and the protrusion intersects with the side surface 50Aa. A side surface 50Ab of the portion 50A on the reflective surface side abuts a side surface 51Ab on the opening side of the hole portion 51A. At the same time, the lower side surface 50Ba of the protrusion 50B abuts the lower side surface 51Ba of the hole 51B, and the reflective surface side side surface 50Bb of the protrusion 50B, which intersects with the side surface 50Ba, contacts the opening side of the hole 51B. It comes into contact with the side surface 51Bb.

Thereby, the position of the second ellipsoidal mirror 50 in the major axis direction and the minor axis direction can be easily and uniquely determined with respect to the second holding member 51.

In some embodiments, the upper side (first focal point side) of the protrusion 50A is in contact with the upper side of the hole 51A, and the upper side of the protrusion 50B is in contact with the upper side of the hole 51B. It is configured to abut against the side surface.

The second holding member 51 holds the flange in a state where the protrusions 50A, 50B are inserted into the holes 51A, 51B and positioned, and the protrusions 50A, 50B are fixed by the holes 51A, 51B. configured to do so. For example, with the projections 50A and 50B fixed by being inserted into the holes 51A and 51B, the flange is fixed to the second holding member 51 by screwing, pinning, crimping, welding, caulking, etc. be done.

FIG. 3E shows a schematic plan view and side view of the second ellipsoidal mirror 50. Note that in FIG. 3E, for convenience of explanation, the plan view represents a view seen from the reflective surface side.

Both the first focal point F3 and the second focal point F4 of the second ellipsoidal mirror 50 are arranged at positions farther from the concave reflecting surface than the flange surface. In FIG. 3E, both the short-axis distance between the reflective surface and the first focal point F3 and the short-axis distance between the reflective surface and the second focal point F4 are the same as the distance between the reflective surface and the flange surface. longer than the distance in the minor axis direction between Note that the flange (surface) formed on the second ellipsoidal mirror 50 is approximately parallel to the long axis connecting the first focal point F3 and the second focal point F4.

The protrusions 50A and 50B are arranged near the first focal point F3 of the two focal points of the second ellipsoidal mirror 50. Specifically, as shown in FIG. 3E, on the surface of the flange formed on the second ellipsoidal mirror 50, the first projection point of the first focal point F3 of the second ellipsoidal mirror 50 (the first projection point relative to the surface of the flange) The straight line connecting the projection point of the focal point F3) and the second projection point of the second focal point F4 (the projection point of the second focal point F4 on the flange surface) is orthogonal to the straight line connecting the first projection point and the protrusion 50A. A protrusion 50A is formed at the position. Similarly, on the surface of the flange formed on the second ellipsoidal mirror 50, a straight line connecting the first projection point of the first focal point F3 of the second ellipsoidal mirror 50 and the second projection point of the second focal point F4; The protrusion 50B is formed at a position where the straight line connecting the first projection point and the protrusion 50B intersects at right angles.

Thereby, the positioning of the first focal point F3 of the second ellipsoidal mirror 50 held by the second holding member 51 can be easily and highly accurately achieved.

As shown in FIGS. 2E and 3E, when the second focal point F2 of the first ellipsoidal mirror 40 and the first focal point F3 of the second ellipsoidal mirror 50 are arranged at substantially the same position, the first elliptical The surface mirror 40 is held by the first holding member 41 by projections 40A and 40B formed near the second focal point F2, and the second ellipsoidal mirror 50 has a projection formed near the first focal point F3. It is held by the second holding member 51 by 50A and 50B.

As described above, the first holding member 41 that holds the first ellipsoidal mirror 40 is fixed (joined) to the second holding member 51 that holds the second ellipsoidal mirror 50 in a predetermined positional relationship. Ru.

FIGS. 4A and 4B show schematic side views of the first holding member 41 fixed to the second holding member 51. In FIGS. 4A and 4B, parts similar to those in FIGS. 2A to 2E and 3A to 3E are denoted by the same reference numerals, and description thereof will be omitted as appropriate.

The first holding member 41 and the second holding member 51 each have a second focal point F2 of the first ellipsoidal mirror 40 and a first focal point of the second ellipsoidal mirror 50 when both members are fixed in a predetermined positional relationship. It is designed to match F3. Therefore, by fixing the first holding member 41 at a predetermined holding position on the second holding member 51, the second focal point F2 of the first ellipsoidal mirror 40 and the first focal point F3 of the second ellipsoidal mirror 50 are approximately In agreement (Fig. 4A, Fig. 4B).

In some embodiments, the relative position of the first holding member 41 in the x and y directions with respect to the second holding member 51 can be changed. For example, as shown in FIG. 4A, with the first holding member 41 held by the second holding member 51, the first ellipsoidal mirror 40 is placed at the first focal point F1 or at a position optically substantially conjugate thereof. The light from the light source is received at the second focal point F4 of the second ellipsoidal mirror 50 or at a position that is optically approximately conjugate thereto. At this time, the second holding member 51 is fixed so that the light from the light source is focused at the second focal point F2 of the first ellipsoidal mirror 40, the first focal point F3 of the second ellipsoidal mirror 50, and the second focal point F4. The relative position of the No. 1 holding member 41 in the x and y directions is determined (FIG. 4B).

5A and 5B show schematic perspective views of the first holding member 41 fixed to the second holding member 51. In FIGS. 5A and 5B, parts similar to those in FIGS. 2A to 2E, 3A to 3E, 4A, and 4B are denoted by the same reference numerals, and description thereof will be omitted as appropriate.

As described above, when the first holding member 41 is held at a predetermined holding position with respect to the second holding member 51, a hole for fixing the pin is formed in the first holding member 41, A hole for inserting a pin is formed in the second holding member 51, and the first holding member 41 is fixed to the second holding member 51 by pinning using pins 55 and 56.

Alternatively, as described above, when the relative position of the first holding member 41 with respect to the second holding member 51 is determined and held at that position, the relative position of the first holding member 41 with respect to the second holding member 51 is determined and held with respect to the second holding member 51 by pinning using the pins 55 and 56. The first holding member 41 is fixed.

Note that in FIGS. 2A to 5B, the case where the holding member according to the embodiment is configured by joining the first holding member 41 and the second holding member 51 has been described, but the configuration according to the embodiment is different from this. It is not limited to. For example, the holding member according to the embodiment may be one in which the first holding member 41 and the second holding member 51 are fixed in advance and integrated.

FIG. 6 schematically shows a side view of the first ellipsoidal mirror 40 and the second ellipsoidal mirror 50 held by the first holding member 41 and the second holding member 51. In FIG. 6, parts similar to those in FIGS. 1 to 5B are designated by the same reference numerals, and description thereof will be omitted as appropriate.

As described above, the first holding member 41 is configured to hold the flange of the first ellipsoidal mirror 40, and the second holding member 51 is configured to hold the flange of the second ellipsoidal mirror 50. Here, as shown in FIG. 5B, the first holding member 41 and the second holding member 51 (that is, the holding member according to the embodiment) that are fixed to each other are connected to the flange (surface) of the first ellipsoidal mirror 40 and the second holding member 51, which are fixed to each other. It is held so that the flange (surface) of the ellipsoidal mirror 50 is substantially parallel (FIG. 6).

As a result, one or more protrusions and one or more The holes allow highly accurate positioning in the x and y directions. As a result, the first ellipsoidal mirror 40 and the second ellipsoidal mirror 50 can be easily aligned with high accuracy at low cost.

Furthermore, both ends of the second ellipsoidal mirror 50 according to the embodiment have a shape cut by a plane that intersects with the long axis direction of the reflecting surface that is a part of the ellipsoidal surface, as described above. By cutting both ends, it is possible to reduce the weight and size, and in particular, by cutting the lower end, it is possible to reduce the burden on the subject to be observed.

7A and 7B schematically show the positional relationship between the first ellipsoidal mirror and the second ellipsoidal mirror and the subject to be observed according to a comparative example of the embodiment. FIG. 7A is a top view schematically showing the positional relationship between a first ellipsoidal mirror and a second ellipsoidal mirror and a subject to be observed according to a comparative example of the embodiment. FIG. 7B is a side view schematically showing the positional relationship between the first ellipsoidal mirror and the second ellipsoidal mirror and the subject to be observed according to a comparative example of the embodiment.

A fundus observation device according to a comparative example of the embodiment includes a first ellipsoidal mirror 40' and a second ellipsoidal mirror 50'. The first ellipsoidal mirror 40' may be similar to the first ellipsoidal mirror 40 according to the embodiment. In contrast, both ends of the second ellipsoidal mirror 50' are not cut along a plane that intersects the long axis of the reflecting surface, which is an ellipsoid (see FIG. 7B).

In this case, when the subject SU brings the second ellipsoidal mirror 50' closer to the face in order to place the subject's eye at the subject's eye position (the position of the second focal point F4 of the second ellipsoidal mirror 50'), the image shown in FIG. 7B As shown, a part of the face (mouth, chin) interferes with the lower part of the second ellipsoidal mirror 50'. Therefore, as shown in FIG. 7A, it becomes necessary for the subject SU to place the subject's eye at the subject's eye position with the face obliquely facing the reflective surface of the second ellipsoidal mirror 50'. This may make it difficult to fixate the subject's eye or may put a strain on the posture of the subject SU during observation.

FIGS. 8A and 8B schematically show the positional relationship between the first ellipsoidal mirror 40 and the second ellipsoidal mirror 50 according to the embodiment and the subject to be observed. FIG. 8A is a top view schematically showing the positional relationship between the first ellipsoidal mirror 40 and the second ellipsoidal mirror 50 and the subject to be observed according to the embodiment. FIG. 8B is a side view schematically showing the positional relationship between the first ellipsoidal mirror 40 and the second ellipsoidal mirror 50 and the subject to be observed according to the embodiment.

As described above, both ends of the second ellipsoidal mirror 50 are cut along a plane that intersects the long axis of the reflecting surface, which is an ellipsoid (see FIG. 8B). In this case, even if the subject SU approaches the second ellipsoidal mirror 50 in order to place the subject's eye at the subject's eye position (the position of the second focal point F4 of the second ellipsoidal mirror 50), as shown in FIG. 8B, Thus, it is possible to prevent the face (mouth, chin) from interfering with the lower part of the second ellipsoidal mirror 50. Therefore, as shown in FIG. 8A, the subject SU can place the eye to be examined at the position of the eye to be examined, facing in front of the reflective surface of the second ellipsoidal mirror 50. This facilitates fixation of the subject's eye and does not place any strain on the posture of the subject SU during observation.

Note that, as shown in FIG. 1, the second ellipsoidal mirror 50 connects a straight line connecting the first focal point F1 and the second focal point F2 of the first ellipsoidal mirror 40 with the first focal point F3 of the second ellipsoidal mirror 50. It is arranged so that the angle it makes with the straight line connecting it to the second focal point F4 is angle α. For example, angle α is 30 degrees. In some embodiments, the second ellipsoidal mirror 50 is configured to be movable relative to the first ellipsoidal mirror 40 to change the angle α.

In such a configuration, the illumination light deflected by the hole mirror 30 placed at the first focal point F1 is reflected by the reflective surface of the first ellipsoidal mirror 40, and is reflected at the second focal point F2 of the first ellipsoidal mirror 40. be guided. The illumination light guided to the second focal point F2 is guided to the reflective surface of the second ellipsoidal mirror 50, is reflected by this reflective surface, and is placed at the second focal point F4 of the second ellipsoidal mirror 50. guided by.

The illumination light guided to the eye E enters the eye through the pupil and is irradiated onto the fundus Ef. The return light of the illumination light reflected on the fundus Ef is emitted to the outside of the eye E through the pupil, travels in the opposite direction along the same path as the outward path, and is guided to the first focal point F1 of the first ellipsoidal mirror 40. . As described above, the return light of the illumination light guided to the first focal point F1 passes through the hole formed in the hole mirror 30 (or passes through the hole mirror 30) and is guided to the slit light receiving optical system 20. .

In some embodiments, at least one of the first ellipsoidal mirror 40 and the second ellipsoidal mirror 50 is a concave mirror with a concave reflecting surface. In some embodiments, the reflective surface of the concave mirror is formed to be a free-form surface.

In addition to the configuration shown in FIG. 1, the fundus observation device 1 may be provided with an alignment optical system for aligning the eye E and the optical system. Further, the fundus observation device 1 may be provided with a focusing mechanism by moving the lens or moving the slit light receiving optical system 20.

Additionally, the fundus observation device 1 may include a configuration for providing functions associated with the examination. For example, the fundus observation device 1 may be provided with a fixation optical system for projecting an optotype (fixation target) onto the fundus Ef of the eye E to be examined. Furthermore, the fundus observation device 1 may be provided with arbitrary elements or units such as members (chin rest, forehead rest, etc.) for supporting the subject's face.

FIG. 9 shows a configuration example of a processing system of the fundus observation device 1 according to the first embodiment. In FIG. 9, parts similar to those in FIG. 1 are designated by the same reference numerals, and description thereof will be omitted as appropriate.

The processing system of the fundus observation device 1 is configured around the control section 60. The control unit 60 controls each part of the fundus observation device 1 .

The control section 60 includes a main control section 61 and a storage section 62. The functions of the main control unit 61 are realized by, for example, a processor. A computer program for controlling the fundus observation device 1 is stored in the storage unit 62 in advance. This computer program includes an illumination light source control program, an image sensor control program, a hole mirror control program, an image formation program, a user interface program, and the like. By operating the main control section 61 according to such a computer program, the control section 60 executes control processing.

(Main control unit 61)
The main control section 61 controls each section of the slit projection optical system 10, the slit light receiving optical system 20, the hole mirror 30, the image forming section 70, and the user interface (UI) section 80.

Control of the slit projection optical system 10 includes control of the illumination light source 11, etc. Controls for the illumination light source 11 include turning on and off the light source, adjusting the amount of light, and adjusting the aperture.

Control of the slit light receiving optical system 20 includes control of the image sensor 21, etc. The image sensor 21 is controlled by setting a movable light-receiving range (virtual aperture range, focal plane) at the fundus conjugate position P, and by controlling the reading of light-receiving results using a rolling shutter method (for example, controlling the illumination pattern). (setting of light reception size corresponding to the size, etc.). Furthermore, control of the image sensor 21 includes reset control, exposure control, charge transfer control, output control, and the like.

Control over the hole mirror 30 includes controlling the angle of the deflection surface that deflects the illumination light. By controlling the angle of the deflection surface, it is possible to control the deflection direction of the illumination light. By controlling the angular range of the deflection surface, it is possible to control the scan range (scan start position and scan end position). The scan speed can be controlled by controlling the speed at which the angle of the deflection surface changes.

The control for the image forming unit 70 includes image forming control that forms an image of the eye E from the light reception result obtained by the image sensor 21.

Control over the UI unit 80 includes control over a display device, control over an operation device (input device), and the like.

(Storage unit 62)
The storage unit 62 stores various data. The data stored in the storage unit 62 includes, for example, light reception results obtained by the image sensor 21, image data of an image formed by the image forming unit 70, information on the eye to be examined, and the like. The eye information to be examined includes information regarding the examinee such as a patient ID and name, and information regarding the eye to be examined such as left eye/right eye identification information.

Furthermore, the storage unit 62 stores various programs and data for operating the fundus observation device 1.

(Image forming section 70)
The image forming unit 70 forms a received light image (fundus image) corresponding to an arbitrary light receiving possible range (virtual aperture range, focal plane) based on the received light results read out from the image sensor 21 using a rolling shutter method. It is possible to do so. The image forming unit 70 is capable of sequentially forming received light images corresponding to the light receiving possible range (aperture range), and forming an image of the eye E from the plurality of formed received light images. Various images (image data) formed by the image forming section 70 are stored in the storage section 62, for example.

For example, the image forming unit 70 includes a processor and implements the above functions by performing processing according to a program stored in a storage unit or the like.

(UI section 80)
The UI unit 80 has a function for exchanging information between the user and the fundus observation device 1. The UI section 80 includes a display device and an operation device. The display device may include a display section, or may include other display devices. The display device displays various information. The display device includes, for example, a liquid crystal display, and displays the above information under control from the main control unit 61. The information displayed on the display device includes information corresponding to the control result by the control unit 60, information (image) corresponding to the calculation result by the image forming unit 70, and the like. The operating device includes various hardware keys and/or software keys. The main control section 61 is capable of receiving operation details on the operating device and outputting control signals corresponding to the operation details to each section. It is possible to integrally configure at least part of the operating device and at least part of the display device. A touch panel display is one example.

The first ellipsoidal mirror 40 is an example of the "first concave mirror" according to the embodiment. The second ellipsoidal mirror 50 is an example of a "second concave mirror" according to the embodiment. The first holding member 41 and the second holding member 51 are examples of "holding members" according to the embodiment. The protrusions 40A, 40B, 50A, and 50B are examples of "fixed parts" according to the embodiment. The holes 41A, 41B, 51A, and 51B are examples of "fixing parts" according to the embodiment. The slit projection optical system 10 and the slit light receiving optical system 20 are an example of an "optical system" according to the embodiment. The hole mirror 30 is an example of a "deflection member" according to the embodiment.

<Operation>
Next, an example of the operation of the fundus observation device 1 according to the first embodiment will be described.

FIG. 10 shows an example of the operation of the fundus observation device 1 according to the first embodiment. FIG. 10 shows a flowchart of an example of the operation of the fundus observation device 1 according to the first embodiment. The storage unit 62 stores a computer program for implementing the processing shown in FIG. The main control unit 61 executes the processing shown in FIG. 10 by operating according to this computer program.

In FIG. 10, it is assumed that the eye E to be examined is placed at a predetermined eye position (second focal point F4 of the second ellipsoidal mirror 50 in FIG. 1).

(S1: Turn on the illumination light source)
The main control unit 61 controls the illumination light source 11 to turn on the illumination light source 11 .

The light output from the illumination light source 11 passes through the opening formed in the iris diaphragm 12, passes through the opening formed in the slit 13, and passes through the projection lens 14, and is transmitted through the hole mirror as slit-shaped illumination light. Guided by 30.

(S2: Deflection control of illumination light, setting the aperture range of the light receiving surface)
Next, by controlling the hole mirror 30, the main controller 61 sets the orientation of the deflection surface in a predetermined deflection direction in order to illuminate a predetermined irradiation range, and changes the orientation of the deflection surface within a predetermined deflection angle range. The deflection control of the illumination light is started by sequentially changing the illumination light. That is, the main control unit 61 starts scanning the fundus Ef with the illumination light.

In some embodiments, the main control unit 61 controls the hole mirror 30 to deflect the illumination light in synchronization with the movement of a virtual aperture range (light receiving range) that can be arbitrarily set in the image sensor 21. Take control.

In some embodiments, the main control unit 61 controls the image sensor 21 to create a virtual aperture range (light-receivable range) that includes the return light reception range on the light-receiving surface corresponding to the illumination light irradiation area on the fundus Ef. Set the target. For example, the irradiation range of the illumination light on the fundus Ef can be specified based on the deflection angle of the deflection surface of the hole mirror 30. The main control unit 61 can virtually set the aperture range on the light receiving surface of the image sensor 21 in accordance with the deflection direction of the deflection surface of the hole mirror 30 that is sequentially changed.

The illumination light guided to the hole mirror 30 is deflected by a deflection surface whose polarization direction has been changed, and is guided to the reflection surface of the first ellipsoidal mirror 40, and is reflected by this reflection surface. The light is guided to the reflecting surface of the second ellipsoidal mirror 50 via the second focal point F2. The illumination light guided to the reflective surface of the second ellipsoidal mirror 50 is reflected by this reflective surface, enters the eye of the eye E to be examined, which is placed at the second focal point F4 of the second ellipsoidal mirror 50, and enters the fundus of the eye. Irradiated to Ef. The return light of the illumination light from the fundus Ef travels in the opposite direction along the same path as the outward path, passes through the hole formed in the hole mirror 30, or is transmitted through the hole mirror 30, and passes through the imaging lens 22. The light is received by the light receiving surface of the image sensor 21. On the light-receiving surface of the image sensor 21, a virtual aperture range (light-receiving range) is set to include the return light reception range corresponding to the illumination light irradiation range on the fundus Ef, so unnecessary scattered light is Only the return light from the fundus Ef is received while suppressing the influence.

(S3: Finished?)
Next, the main control unit 61 determines whether or not to finish scanning the fundus Ef with the illumination light. For example, the main control unit 61 finishes scanning the illumination light on the fundus Ef by determining whether the deflection angle of the deflection surface of the hole mirror 30, which is sequentially changed, is within a predetermined deflection angle range. It can be determined whether or not.

When it is determined that scanning of the fundus Ef with the illumination light is to be completed (S3: Y), the operation of the fundus observation device 1 moves to step S4. When it is determined that scanning of the fundus Ef with the illumination light is not completed (S3: N), the operation of the fundus oculi observation device 1 moves to step S2.

(S4: Acquire image)
In step S3, when it is determined to end the scanning of the illumination light on the fundus Ef (S3: Y), the main control unit 61 controls the image forming unit 70 to control the light reception results read out from the image sensor 21. An image of the eye E to be examined is formed based on. In some embodiments, the image forming unit 70 sequentially forms received light images based on the received light results read from the image sensor 21 in step S2, and determines the image of the eye E from the plurality of formed received light images. form.

This is the end of the operation of the fundus observation device 1 (end).

As described above, according to the first embodiment, the first ellipsoidal mirror 40 and the second ellipsoidal mirror 50 can be easily aligned with high accuracy at low cost. Furthermore, in the fundus observation device 1 equipped with such a first ellipsoidal mirror 40 and a second ellipsoidal mirror 50, the optical path of the slit projection optical system 10 and the optical path of the slit light receiving optical system 20 are connected using the hole mirror 30. At the same time, the illumination light is deflected using the hole mirror 30 and guided to the reflecting surface of the first ellipsoidal mirror 40. As a result, with a low cost and compact configuration, it is possible to secure a photographing angle of view of over 80 degrees using only the optical system that scans in the slit width direction (line width direction) perpendicular to the slit direction of the illumination light, while providing a wide-angle It becomes possible to easily arrange a shared optical system for the optical path of the illumination light and the optical path of the return light. Furthermore, since the optical system can be placed on the passage (transmission) side of the hole portion of the hole mirror 30, the configuration does not require a pupil relay system, and the degree of freedom in the arrangement of the optical system can be improved.

Furthermore, by using a hole mirror 30 instead of a polygon mirror or the like, it is possible to widen the deflection angle range while reducing noise. Furthermore, by making the length in the slit direction or the length in the scanning direction variable, the scanning range of the illumination light can be set arbitrarily.

<Second embodiment>
The configuration of the fundus observation apparatus according to the embodiment is not limited to the configuration of the fundus observation apparatus 1 according to the first embodiment. For example, the fundus observation device 1 according to the first embodiment may further include an OCT optical system.

Hereinafter, in the embodiment, a case in which a swept source type OCT technique is used in measurement or imaging using OCT will be particularly described. However, it is also possible to apply the configuration according to the embodiment to a fundus observation apparatus that uses other types (for example, spectral domain type) of OCT.

Hereinafter, the fundus observation device according to the second embodiment will be described, focusing on the differences from the fundus observation device 1 according to the first embodiment.

<Configuration>
FIG. 11 shows an example of the configuration of the optical system of the fundus observation device according to the second embodiment. In FIG. 11, parts similar to those in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted as appropriate.

The configuration of the optical system of the fundus observation device 1a according to the second embodiment is different from the configuration of the optical system of the fundus observation device 1 according to the first embodiment. This is the point where system 100 has been added. The optical path of the OCT optical system 100 is coupled to the optical path of the slit light receiving optical system 20 through an optical path between the slit light receiving optical system 20 and the hole mirror 30.

Specifically, a relay lens optical system including relay lenses 71 and 72 is arranged on the optical path between the slit light receiving optical system 20 and the hole mirror 30. The optical path between the relay lens 71 and the relay lens 72 is converted into an optical path of a telecentric optical system, and a dichroic mirror 90 is arranged in the optical path of the telecentric optical system. That is, the relay lens optical system converts at least a portion of the optical path in which the dichroic mirror 90 is arranged into the optical path of the telecentric optical system.

The dichroic mirror 90 is an optical path coupling/separation member that separates the optical path of the OCT optical system 100 from the optical path of the slit light receiving optical system 20 (combines the optical path of the slit light receiving optical system 20 and the optical path of the OCT optical system 100). The dichroic mirror 90 reflects the measurement light from the OCT optical system 100 and guides it to the relay lens 71, and also reflects the return light of the measurement light from the eye E to be examined and guides it to the OCT optical system 100. Furthermore, the dichroic mirror 90 transmits the return light of the illumination light from the eye E that has been guided through the relay lens 71 and guides it to the relay lens 72 .

(OCT optical system 100)
FIG. 12 shows a configuration example of the OCT optical system 100 of FIG. 11. In FIG. 12, parts similar to those in FIG. 11 are designated by the same reference numerals, and description thereof will be omitted as appropriate.

The OCT optical system 100 is provided with an optical system for performing OCT measurement (or OCT imaging) on the eye E to be examined. This optical system splits light from a wavelength swept type (wavelength scanning type) light source into measurement light and reference light, and causes interference between the return light of the measurement light from the eye E and the reference light that has passed through the reference optical path. This is an interference optical system that generates interference light and detects this interference light. The detection result (detection signal) of the interference light by the interference optical system is an interference signal indicating the spectrum of the interference light, and is sent to an image forming section 70a, a data processing section 75a, etc., which will be described later.

The OCT light source 101 is configured to include a wavelength sweep type (wavelength scanning type) light source that can sweep (scan) the wavelength of emitted light, similar to a general swept source type fundus observation device. The wavelength swept light source includes, for example, a laser light source that includes a resonator and emits light with a center wavelength of 1050 nm. The OCT light source 101 temporally changes the output wavelength in a near-infrared wavelength band that is invisible to the human eye.

The light L0 output from the OCT light source 101 is guided to the polarization controller 103 through the optical fiber 102, and its polarization state is adjusted. The polarization controller 103 adjusts the polarization state of the light L0 guided within the optical fiber 102, for example, by applying external stress to the looped optical fiber 102.

The light L0 whose polarization state has been adjusted by the polarization controller 103 is guided to the fiber coupler 105 through the optical fiber 104 and split into the measurement light LS and the reference light LR.

The reference light LR is guided to a collimator 111 by an optical fiber 110, converted into a parallel light beam, and guided to an optical path length changing unit 114 via an optical path length correction member 112 and a dispersion compensation member 113. The optical path length correction member 112 acts to match the optical path length of the reference light LR and the optical path length of the measurement light LS. The dispersion compensation member 113 acts to match the dispersion characteristics between the reference light LR and the measurement light LS.

The optical path length changing unit 114 is movable in the direction of the arrow shown in FIG. 12, and changes the optical path length of the reference light LR. This movement changes the length of the optical path of the reference light LR. This change in the optical path length is used for correcting the optical path length according to the axial length of the eye E to be examined, adjusting the interference state, and the like. The optical path length changing unit 114 includes, for example, a corner cube and a moving mechanism that moves the corner cube. In this case, the corner cube of the optical path length changing unit 114 turns back the traveling direction of the reference light LR, which has been made into a parallel light beam by the collimator 111, in the opposite direction. The optical path of the reference light LR entering the corner cube and the optical path of the reference light LR exiting from the corner cube are parallel.

The reference light LR that has passed through the optical path length changing unit 114 passes through the dispersion compensating member 113 and the optical path length correcting member 112, is converted from a parallel beam into a convergent beam by the collimator 116, and enters the optical fiber 117. The reference light LR incident on the optical fiber 117 is guided to a polarization controller 118 to have its polarization state adjusted, guided to an attenuator 120 by an optical fiber 119 to have its light amount adjusted, and then sent to a fiber coupler 122 by an optical fiber 121. be guided.

On the other hand, the measurement light LS generated by the fiber coupler 105 is guided by the optical fiber 127 and made into a parallel light beam by the collimator lens unit 140. The parallel light beam LS is deflected one-dimensionally or two-dimensionally by the optical scanner 150.

The collimator lens unit 140 includes a collimator lens arranged on the optical axis of the interference optical system included in the OCT optical system 100. The collimator lens converts the light flux of the measurement light emitted from the end of the optical fiber connected to the OCT optical system 100 and guiding the measurement light LS into a parallel light flux. The end of the optical fiber is placed, for example, at a fundus conjugate position P.

The optical scanner 150 (deflection surface) can be placed at the pupil conjugate position Q. When deflecting the illumination light one-dimensionally, the optical scanner 150 includes a galvano scanner that deflects the measurement light LS within a predetermined deflection angle range based on a predetermined deflection direction. When deflecting the illumination light two-dimensionally, the optical scanner 150 includes a first galvano scanner and a second galvano scanner. The first galvano scanner deflects the measurement light LS so as to move the irradiation position in a horizontal direction (for example, the x direction) perpendicular to the optical axis of the OCT optical system 100. The second galvano scanner deflects the measurement light LS deflected by the first galvano scanner so as to move the irradiation position in a vertical direction (for example, the y direction) perpendicular to the optical axis of the OCT optical system 100. Examples of scanning modes for moving the irradiation position of the measurement light LS by the optical scanner 150 include horizontal scanning, vertical scanning, cross scanning, radial scanning, circular scanning, concentric scanning, and spiral scanning.

The measurement light LS deflected by the optical scanner 150 passes through the focusing lens 151, is reflected by the dichroic mirror 90, passes through the hole of the hole mirror 30, is guided to the reflective surface of the first ellipsoidal mirror 40, The illumination light from the slit projection optical system 10 is guided to the eye E through the same path. The focusing lens 151 is movable along the optical path of the measurement light LS (optical axis of the OCT optical system 100). The focusing lens 151 is moved along the optical path of the measurement light LS by a moving mechanism (not shown) under the control of a control section that will be described later.

The measurement light LS reflected by the reflective surface of the second ellipsoidal mirror 50 enters the eye through the pupil of the eye E at the second focal point F4 (position of the eye to be examined). The measurement light LS is scattered (including reflection) at various depth positions of the eye E to be examined. The return light of the measurement light LS including such backscattered light travels in the opposite direction along the same path as the forward path, is guided to the fiber coupler 105, and reaches the fiber coupler 122 via the optical fiber 128.

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

The detector 125 is, for example, a balanced photodiode that has a pair of photodetectors that respectively detect a pair of interference lights LC, and outputs a difference between the detection results obtained by these photodetectors. The detector 125 sends the detection result (interference signal) to a DAQ (Data Acquisition System) 130. A clock KC is supplied to the DAQ 130 from the OCT light source 101. The clock KC is generated in the OCT light source 101 in synchronization with the output timing of each wavelength swept (scanned) within a predetermined wavelength range by the wavelength sweep type light source. For example, the OCT light source 101 optically delays one of the two branched lights obtained by branching the light L0 of each output wavelength, and then outputs the clock KC based on the result of detecting these combined lights. generate. The DAQ 130 samples the detection result of the detector 125 based on the clock KC. The DAQ 130 sends the sampled detection results of the detector 125 to the image forming section 70a, the data processing section 75a, and the like. The image forming unit 70a (or the data processing unit 75a) performs Fourier transform or the like on the spectral distribution based on the detection results obtained by the detector 125, for example, for each series of wavelength scans (for each A line). A reflection intensity profile at each A-line is formed. Further, the image forming unit 70a forms image data by converting the reflection intensity profile of each A line into an image.

Note that in FIG. 12, the optical path length difference between the measurement light and the reference light is changed by changing the optical path length of the reference light, but the configuration according to the embodiment is not limited to this. For example, the optical path length difference between the measurement light and the reference light may be changed by changing the optical path length of the measurement light.

FIG. 13 shows a configuration example of a processing system of the fundus observation apparatus 1a according to the second embodiment. In FIG. 13, parts similar to those in FIG. 9, FIG. 11, or FIG. 12 are denoted by the same reference numerals, and description thereof will be omitted as appropriate.

The configuration of the processing system of the fundus observation device 1a differs from that of the fundus observation device 1 in that a control unit 60a is provided in place of the control unit 60, and an image forming unit is provided in place of the image forming unit 70. 70a is provided, and a data processing section 75a and an OCT optical system 100 are added.

The control unit 60a includes a main control unit 61a and a storage unit 62a, and in addition to the control executable by the control unit 60, controls the image forming unit 70a, the data processing unit 75a, and the OCT optical system 100. . The functions of the main control section 61a, like the main control section 61, are realized by, for example, a processor. Similar to the storage unit 62, the storage unit 62a stores in advance a computer program for controlling the fundus observation device 1a. This computer program includes an illumination light source control program, an image sensor control program, a hole mirror control program, an image formation program, a data processing program, an OCT optical system control program, a user interface program, etc. . By operating the main control section 61a according to such a computer program, the control section 60a executes control processing.

The main control section 61a controls each section of the slit projection optical system 10, the slit light receiving optical system 20, the hole mirror 30, the image forming section 70a, the data processing section 75a, the OCT optical system 100, and the UI section 80.

Control of the OCT optical system 100 includes control of the OCT light source 101, operation control of the polarization controllers 103 and 118, movement control of the optical path length changing unit 114, operation control of the attenuator 120, control of the detector 125, control of the DAQ 130, There are controls for the optical scanner 150, controls for the moving mechanism 151D, and the like.

Controls for the OCT light source 101 include turning on and off the light source, adjusting the light amount, and adjusting the aperture. Control of the detector 125 includes exposure adjustment, gain adjustment, detection rate adjustment, etc. of the detection element. Control of the optical scanner 150 includes control of the scan position, scan range, and scan speed by the optical scanner 150.

The moving mechanism 151D moves the focusing lens 151 in the optical axis direction of the OCT optical system 100. By controlling the moving mechanism 151D, the main control unit 61a can move the focusing lens 151 in the optical axis direction of the OCT optical system 100 and change the focusing position of the measurement light. The focal position of the measurement light LS corresponds to the depth position (z position) of the beam waist of the measurement light LS.

The image forming unit 70a is controlled by OCT based on the interference light detection result obtained by the OCT optical system 100, in addition to image formation control for forming an image of the eye E from the light reception result obtained by the image sensor 21. This includes image formation control, etc.

The control for the data processing section 75a includes control of image processing for the image formed by the image forming section 70a, control of image analysis processing, etc.

Similar to the image forming section 70, the image forming section 70a creates a received light image (fundus of the eye) corresponding to a virtually set arbitrary aperture range (light receiving possible range) based on the light receiving results read out from the image sensor 21. image). The image forming unit 70a can sequentially form received light images corresponding to the virtual aperture range, and form an image of the eye E from the plurality of formed received light images.

Further, the image forming unit 70a forms image data of an OCT image (tomographic image) based on a detection signal input from the DAQ 130 (detector 125) and a pixel position signal input from the control unit 60a. OCT images formed by the image forming section 70a include A-scan images, B-scan images, and the like. A B-scan image is formed, for example, by arranging A-scan images in the B-scan direction. Similar to conventional swept source type OCT, this processing includes processing such as noise removal (noise reduction), filter processing, dispersion compensation, and FFT (Fast Fourier Transform). In the case of other types of OCT apparatuses, the image forming section 70a executes known processing depending on the type. Various images (image data) formed by the image forming section 70a are stored, for example, in the storage section 62a.

The data processing unit 75a processes an image formed based on the light reception result obtained by the slit light reception optical system 20 or data acquired by OCT measurement of the eye E to be examined. The data processing section 75a can perform various image processing and analysis processing on the image formed by the image forming section 70a. For example, the data processing unit 75a executes various correction processes such as image brightness correction.

The data processing unit 75a executes known image processing such as interpolation processing for interpolating pixels between OCT images to form image data of a three-dimensional image of the fundus Ef. Note that the image data of a three-dimensional image means image data in which pixel positions are defined by a three-dimensional coordinate system. Image data of a three-dimensional image includes image data consisting of voxels arranged three-dimensionally. This image data is called volume data or voxel data. When displaying an image based on volume data, the data processing unit 75a performs rendering processing (volume rendering, MIP (Maximum Intensity Projection: maximum intensity projection), etc.) on this volume data to display an image that is viewed from a specific viewing direction. image data of a pseudo three-dimensional image is created. This pseudo three-dimensional image is displayed on the display device included in the UI section 80.

It is also possible to form stack data of multiple tomographic images as image data of a three-dimensional image. Stack data is image data obtained by three-dimensionally arranging a plurality of tomographic images obtained along a plurality of scan lines based on the positional relationship of the scan lines. In other words, stack data is image data obtained by expressing multiple tomographic images, which were originally defined by individual two-dimensional coordinate systems, using one three-dimensional coordinate system (that is, embedding them in one three-dimensional space). be.

The data processing unit 75a performs various types of rendering on the acquired three-dimensional data set (volume data, stack data, etc.) to create a B-mode image (longitudinal image, axial cross-sectional image) in an arbitrary cross section, It is possible to form C-mode images (cross-sectional images, horizontal sectional images), projection images, shadowgrams, and the like. An image of an arbitrary cross section, such as a B-mode image or a C-mode image, is formed by selecting pixels (pixels, voxels) on a specified cross-section from a three-dimensional data set. A projection image is formed by projecting a three-dimensional data set in a predetermined direction (z direction, depth direction, axial direction). A shadowgram is formed by projecting a part of a three-dimensional data set (for example, partial data corresponding to a specific layer) in a predetermined direction. An image, such as a C-mode image, a projection image, or a shadowgram, whose viewpoint is the front side of the subject's eye is called an en-face image.

The data processing unit 75a generates a B-mode image or a frontal image (vessel-enhanced image, angiogram) in which retinal blood vessels and choroidal blood vessels are emphasized based on data (for example, B-scan image data) collected in time series by OCT. can be constructed. For example, time-series OCT data can be collected by repeatedly scanning substantially the same region of the eye E to be examined.

In some embodiments, the data processing unit 75a compares time-series B-scan images obtained by B-scans of substantially the same region, and converts the pixel value of the portion where the signal intensity changes into a pixel value corresponding to the change. By performing the conversion, an enhanced image is constructed in which the changed portion is emphasized. Furthermore, the data processing unit 75a forms an OCTA image by extracting information for a predetermined thickness at a desired site from the constructed plurality of emphasized images and constructing it as an en-face image.

Images generated by the data processing unit 75a (for example, three-dimensional images, B-mode images, C-mode images, projection images, shadowgrams, and OCTA images) are also included in OCT images.

Furthermore, the data processing unit 75a generates an image formed based on the light reception result obtained by the slit light reception optical system 20, an interference light detection result obtained by OCT measurement, or an OCT image formed based on the detection result. A predetermined analysis process is performed on the image. The predetermined analysis process includes identifying a predetermined region (tissue, lesion) in the eye E; calculating the distance (interlayer distance), area, angle, ratio, and density between the specified regions; and using a specified calculation formula. identification of the shape of a predetermined part; calculation of these statistical values; calculation of the distribution of measured values and statistical values; and image processing based on the results of these analysis processes. Predetermined tissues include blood vessels, optic disc, fovea, macula, and the like. Predetermined lesions include vitiligo, hemorrhage, and the like.

The fundus observation device 1a may include a movement mechanism that moves the OCT optical system 100 in a one-dimensional direction or two-dimensional direction intersecting the optical axis of the OCT optical system 100. In this case, the main controller 61a moves the OCT optical system 100 relative to the dichroic mirror 90 in a one-dimensional direction or two-dimensional direction intersecting the optical axis of the OCT optical system 100 by controlling this moving mechanism. Thereby, by moving the scan range using the optical scanner 150 of the OCT optical system 100, it becomes possible to scan a wide-angle scan range (for example, the SLO imaging range) in the fundus Ef.

The OCT optical system 100 is an example of a "projection optical system" and a "light receiving optical system" according to the embodiment.

<Operation>
Next, an example of the operation of the fundus observation device 1a according to the second embodiment will be described.

The fundus observation device 1a is capable of performing OCT measurement using the OCT optical system 100 in parallel with scanning control of the fundus Ef using illumination light shown in FIG. The OCT measurement control that can be executed in parallel with the control shown in FIG. 10 will be described below.

FIG. 14 shows an example of the operation of the fundus observation device 1a according to the second embodiment. FIG. 14 shows a flowchart of an example of the operation of the fundus observation device 1a according to the second embodiment. A computer program for implementing the process shown in FIG. 14 is stored in the storage unit 62a. The main control unit 61a executes the processing shown in FIG. 14 by operating according to this computer program.

In FIG. 14, it is assumed that the eye E to be examined is placed at a predetermined eye position (second focal point F4 of the second ellipsoidal mirror 50 in FIG. 1).

(S11: Set scan range)
First, the main controller 61a sets the scan range of the optical scanner 150. The main control unit 61a can set the scan range, the scan start position, scan end position, scan speed (scan frequency), etc. of the optical scanner 150.

In some embodiments, the user can specify the scan mode or operation mode by operating the operating device on the UI unit 80. When a scan mode (for example, horizontal scan, vertical scan) is specified by the user through an operation on the operation device, the main control unit 61a analyzes the operation information from the operation device and identifies the specified scan mode. When the user specifies an operation mode by operating the operation device, the main control unit 61a analyzes the operation information and selects a prespecified scan mode (for example, horizontal scan mode) in the specified operation mode (OCT measurement mode). , vertical scan).

(S12: Turn on the OCT light source)
Next, the main control unit 61a controls the OCT light source 101 to turn on the OCT light source 101. In some embodiments, the main control unit 61a executes step S12 in synchronization with the lighting control of the illumination light source 11 in step S1 shown in FIG.

In some embodiments, the main control unit 61a executes focus adjustment control and polarization adjustment control. For example, the main controller 61a controls the moving mechanism 151D to move the focusing lens by a predetermined distance, and then controls the OCT optical system 100 to perform OCT measurement. The main control unit 61a causes the data processing unit 75a to determine the focus state of the measurement light LS based on the detection result of the interference light obtained by OCT measurement. For example, the data processing unit 75a calculates a predetermined evaluation value regarding the image quality of the OCT image by analyzing the detection result of interference light obtained by OCT measurement, and determines the focus state based on the calculated evaluation value. do. When it is determined that the focus state of the measurement light LS is not appropriate based on the determination result by the data processing unit 75a, the main control unit 61a controls the moving mechanism 151D again, and it is determined that the focus state is appropriate. Repeat until

For example, the main controller 61a controls at least one of the polarization controllers 103 and 118 to change the polarization state of at least one of the light L0 and the measurement light LS by a predetermined amount, and then changes the OCT optical system 100. The image forming section 70a controls and executes OCT measurement, and causes the image forming section 70a to form an OCT image based on the detection result of the acquired interference light. The main control unit 61a causes the data processing unit 75a to determine the image quality of the OCT image obtained by OCT measurement. When it is determined that the polarization state of the measurement light LS is not appropriate based on the determination result by the data processing unit 75a, the main control unit 61a controls the polarization controllers 103 and 118 again to ensure that the polarization state is appropriate. Repeat until it is determined that

(S13: Execute OCT scan)
Next, the main controller 61a deflects the measurement light LS generated based on the light L0 emitted from the OCT light source 101 by controlling the optical scanner 150, and uses the deflected measurement light LS to illuminate the eye E. A predetermined part of the fundus Ef is scanned. The detection result of the interference light obtained by the OCT measurement is sampled in the DAQ 130 and stored as an interference signal in the storage unit 62a or the like.

(S14: Ended?)
Next, the main control unit 61a determines whether to end the OCT scan of the fundus Ef. For example, the main control unit 61a determines whether or not the deflection angle of the deflection surface of the optical scanner 150, which is sequentially changed, is within a predetermined deflection angle range, thereby determining whether or not to end the OCT scan of the fundus Ef. It is possible to determine whether

When it is determined that the OCT scan of the fundus Ef is to be completed (S14: Y), the operation of the fundus observation device 1a moves to step S15. When it is determined that the OCT scan of the fundus Ef is not completed (S14: N), the operation of the fundus observation device 1a moves to step S13.

(S15: Form OCT image)
In step S14, when it is determined to end the OCT scan on the fundus Ef (S14: Y), the main control unit 61a scans the fundus Ef along the B-scan direction based on the interference signal acquired in step S14. The image forming section 70a forms an A-scan image. In some embodiments, the main control unit 61a controls the data processing unit 75a to form OCT images such as three-dimensional OCT images, B-mode images, C-mode images, projection images, shadowgrams, and OCTA images. let

This is the end of the operation of the fundus observation device 1a.

FIG. 15 shows an explanatory diagram of the operation of the fundus observation device 1a according to the second embodiment.

As shown in FIG. 15, the scan of the illumination light on the fundus Ef is realized by deflecting the illumination light using the hole mirror 30, and the fundus is realized by deflecting the measurement light LS using the optical scanner 150. The OCT scan in Ef is performed in parallel. As a result, when illumination light scanning is being performed in the scan range SC1 (horizontal direction H0 x vertical direction V0) in the fundus Ef, an OCT scan is performed for the scan range SC0 at an arbitrary position within the scan range SC1. can do.

As a result, it becomes possible to perform OCT measurement (OCT photography) on any position of the fundus observed at a large wide angle by scanning the illumination light in the scan range SC1.

As explained above, according to the second embodiment, in addition to the effects obtained by the first embodiment, the OCT optical system 100 is By symmetrical coupling, the optical path of wide-angle illumination light and the optical path of its return light can be separated at low cost. In addition, it is possible to perform OCT measurement (OCT photography) at any position on the fundus observed at a large wide angle without having to share the optical scanner for OCT scanning and the optical scanner for deflecting illumination light. become.

<Third embodiment>
In the first embodiment and the second embodiment, the second ellipsoidal mirror 50 connects the straight line connecting the first focal point F1 and the second focal point F2 of the first ellipsoidal mirror 40 with the first focal point F1 of the second ellipsoidal mirror 50. A case has been described in which the focal point F3 and the second focal point F4 are arranged so that the angle α between the focal point F3 and the straight line connecting the second focal point F4 is 30 degrees. However, the configuration according to the embodiment is not limited to this. For example, the angle between the straight line connecting the first focal point F1 and the second focal point F2 of the first ellipsoidal mirror 40 and the straight line connecting the first focal point F3 and the second focal point F4 of the second ellipsoidal mirror 50. α may be approximately 0 degrees.

FIG. 16 shows an example of the configuration of the optical system of the fundus observation device according to the third embodiment. In FIG. 16, parts similar to those in FIG. 11 are denoted by the same reference numerals, and description thereof will be omitted as appropriate.

The configuration of the optical system of the fundus observation device 1b according to the third embodiment is different from the configuration of the optical system of the fundus observation device 1a according to the second embodiment. It is the arrangement. In the fundus observation device 1b, the second ellipsoidal mirror 50 connects a straight line connecting the first focal point F1 and the second focal point F2 of the first ellipsoidal mirror 40, and the first focal point F3 and the second focal point F3 of the second ellipsoidal mirror 50. It is arranged so that the angle α between it and the straight line connecting it to the focal point F4 is 0.2 degrees (approximately 0 degrees).

Note that in FIG. 16, the fundus observation device 1b is provided with the OCT optical system 100, but the fundus observation device 1b has a configuration in which the OCT optical system 100 is omitted, as in FIG. Good too.

Depending on the above-mentioned angle α, the wide-angle range and the symmetry of the observation range with respect to the eye E to be examined change. According to the third embodiment, compared to the second embodiment, it becomes possible to observe the fundus Ef in a wide-angle range that is symmetrical with respect to the eye E to be examined.

<Fourth embodiment>
In the first embodiment, a case has been described in which the illumination light is deflected using the hole mirror 30, but the configuration according to the embodiment is not limited to this. In the first embodiment, for example, a reflecting mirror may be placed at the first focal point F1 of the first ellipsoidal mirror 40, and a hole mirror may be placed at a position that is optically approximately conjugate with the pupil of the eye E. .

FIG. 17 shows an example of the configuration of the optical system of the fundus observation device according to the fourth embodiment. In FIG. 17, the same parts as in FIG. 1 are denoted by the same reference numerals, and descriptions thereof will be omitted as appropriate.

The configuration of the optical system of the fundus observation device 1c according to the fourth embodiment is different from the configuration of the optical system of the fundus observation device 1 according to the first embodiment. A reflection mirror 31 is placed in place of the mirror 30, a hole mirror 32 is placed at the pupil conjugate position Q away from the first focal point F1, and light is transmitted between the hole mirror 32 and the slit projection optical system 10. The scanner 17 is arranged, and the relay lenses 33, 15, and 16 for relaying the pupil conjugate position Q are added.

The direction of the deflection surface of the reflection mirror 31 is fixed. The relay lens 33 is arranged between the reflecting mirror 31 and the hole mirror 32. The hole mirror 32 separates or combines the optical path of the slit projection optical system 10 and the optical path of the slit light receiving optical system 20. The direction of the deflection surface of the hole mirror 32 is fixed. A relay lens 16, an optical scanner 17, and a relay lens 15 are arranged between the hole mirror 32 and the slit projection optical system 10. The optical scanner 17 is a uniaxial optical scanner that performs the same deflection operation of illumination light as the hole mirror 30.

In this case, the illumination light from the slit projection optical system 10 passes through the relay lens 15 and is deflected by the optical scanner 17. The illumination light deflected by the optical scanner 17 passes through the relay lens 16 , is deflected in the peripheral area of the hole formed in the hole mirror 32 , and is guided to the relay lens 33 . The illumination light guided to the relay lens 33 is reflected by the reflecting mirror 31 and guided to the reflecting surface of the first ellipsoidal mirror 40. The return light of the illumination light from the fundus Ef of the eye E to be examined is deflected by the reflection mirror 31, passes through the relay lens 33, passes through the hole of the hole mirror 32, and is guided to the slit light receiving optical system 20.

According to the fourth embodiment, compared to the first embodiment, the pupil conjugate position Q can be relayed even if there is not enough space to arrange the optical system near the first focal point F1 of the first ellipsoidal mirror 40. By doing so, the degree of freedom in arranging the slit projection optical system 10 and the slit light receiving optical system 20 can be improved.

<Fifth embodiment>
In the second embodiment, a case has been described in which the illumination light is deflected using the hole mirror 30, but the configuration according to the embodiment is not limited to this. In the second embodiment, similarly to the fourth embodiment, for example, a reflecting mirror of the first focal point F1 of the first ellipsoidal mirror 40 is arranged, and a hole mirror is placed at a position optically substantially conjugate with the pupil of the eye E. You may also place .

FIG. 18 shows an example of the configuration of the optical system of the fundus observation device according to the fifth embodiment. In FIG. 18, parts similar to those in FIG. 11 or FIG. 17 are designated by the same reference numerals, and description thereof will be omitted as appropriate.

The configuration of the optical system of the fundus observation device 1d according to the fifth embodiment is different from the configuration of the optical system of the fundus observation device 1a according to the second embodiment. A reflection mirror 31 is placed in place of the mirror 30, a hole mirror 32 is placed at the pupil conjugate position Q away from the first focal point F1, and light is transmitted between the hole mirror 32 and the slit projection optical system 10. The scanner 17 is arranged, and the relay lenses 15 and 16 for relaying the pupil conjugate position Q are added.

Similarly to the fourth embodiment, the directions of the deflection surfaces of the reflecting mirror 31 and the hole mirror 32 are fixed. The pupil conjugate position Q is relayed by relay lenses 71 and 72. The hole mirror 32 separates or combines the optical path of the slit projection optical system 10 and the optical path of the slit light receiving optical system 20. A relay lens 16, an optical scanner 17, and a relay lens 15 are arranged between the hole mirror 32 and the slit projection optical system 10. The optical scanner 17 is a uniaxial optical scanner that performs the same deflection operation of illumination light as the hole mirror 30.

In this case, the illumination light from the slit projection optical system 10 passes through the relay lens 15 and is deflected by the optical scanner 17. The illumination light deflected by the optical scanner 17 passes through the relay lens 16, is deflected in the peripheral area of the hole formed in the hole mirror 32, passes through the relay lens 72, the dichroic mirror 90, and the relay lens 71, It is reflected by the reflecting mirror 31 and guided to the reflecting surface of the first ellipsoidal mirror 40 . The return light of the illumination light from the fundus Ef of the eye E to be examined is deflected by the reflection mirror 31, passes through the relay lens 71, dichroic mirror 90, and relay lens 72, passes through the hole of the hole mirror 32, and is received by the slit. It is guided to an optical system 20.

According to the fifth embodiment, compared to the second embodiment, the pupil conjugate position Q can be relayed even if there is not enough space to arrange the optical system near the first focal point F1 of the first ellipsoidal mirror 40. By doing so, the degree of freedom in arranging the slit projection optical system 10 and the slit light receiving optical system 20 can be improved.

[Effect]
A fundus observation device according to an embodiment will be described.

A first aspect of the embodiment is an optical system (slit projection optical system) that projects light from a light source (illumination light source 11, OCT light source 101) onto the fundus (Ef) of the eye (E) to be examined, and receives return light from the fundus. system 10, slit light-receiving optical system 20, OCT optical system 100), and two concave mirrors (first A fundus observation device (1, 1a, 1b, 1c, 1d). At least one of the two concave mirrors has a flange in which one of a fixed part and a fixed part is formed. The other of the fixing part and the fixed part is formed in the holding member. The fundus observation device is configured such that the flange is held by the holding member while the part to be fixed is fixed by the fixing part.

According to this aspect, one of the fixed part and the fixed part is formed on the flange of at least one of the two concave mirrors, the other of the fixed part and the fixed part is formed in the holding member, and the fixed part is fixed. Since the holding member is configured to hold the flange in a state where it is fixed by the flange, it is possible to easily and accurately adjust the position of the concave mirror as an optical member with respect to the holding member. become.

In a second aspect of the embodiment, in the first aspect, the two concave mirrors include a first concave mirror (a first ellipsoidal mirror) having a first flange formed on the peripheral edge and a concave first reflective surface that reflects light. 40); and a second concave mirror (second ellipsoidal mirror 50) having a second flange formed on its peripheral edge and having a concave second reflecting surface that guides the light reflected by the first concave mirror to the fundus. . The holding member holds the first flange and the second flange.

According to this aspect, the holding member holds the flange formed on the peripheral edge of the concave mirror while fixing the concave mirror by the fixing part and the fixed part, so that the holding member can be easily and accurately positioned. It becomes possible to securely hold the matched concave mirror.

In the third aspect of the embodiment, in the second aspect, the holding member holds the first flange and the second flange so that they are substantially parallel.

According to this aspect, the positional relationship between the concave mirror and the holding member can be adjusted while the positional relationship in the predetermined direction is uniquely determined by the holding member, so that the concave mirror relative to the holding member can be easily and It becomes possible to perform positioning with high precision.

In a fourth aspect of the embodiment, in any of the first to third aspects, both ends of at least one of the two concave mirrors in the predetermined first direction (long axis direction of the ellipsoidal mirror) are arranged in the first direction. It has a shape cut by intersecting planes.

According to this aspect, it is possible to reduce the weight and size of the fundus observation device while ensuring the size of the reflective surface necessary for wide-angle fundus observation. In particular, it is possible to avoid situations where the patient's mouth and jaw interfere with the concave mirror, and the patient can observe the patient's eye while facing the reflective surface. .

In a fifth aspect of the embodiment, in any of the first to fourth aspects, at least one of the two concave mirrors is an ellipsoidal mirror (first ellipsoidal mirror 40, second ellipsoidal mirror 50). .

According to such an aspect, it is possible to provide a fundus observation device that can easily and accurately align the ellipsoidal mirror.

In a sixth aspect of the embodiment, in the fifth aspect, the ellipsoidal mirror has a flange in which one of the fixed part and the fixed part is formed, and in the plane of the flange, the first of the two focal points of the ellipsoidal mirror A straight line connecting the projection point and the second projection point is perpendicular to a straight line connecting the first projection point and one of the fixed part and the fixed part.

According to this aspect, the vicinity of the focal point of the ellipsoidal mirror can be fixed to the holding member by the fixing part and the fixed part, so that highly accurate positioning of the ellipsoidal mirror is possible.

In the seventh aspect of the embodiment, in any of the first to sixth aspects, the fixed part is a convex part ( projections 40A, 40B, 50A, 50B), and the fixed part is a concave part or a hole part ( 41A, 41B, 51A, 51B).

According to this aspect, the holding member holds the concave mirror by fitting the convex portion and the concave portion or inserting the convex portion into the hole, which is simple and inexpensive. It becomes possible to align the concave mirror with high precision.

In an eighth aspect of the embodiment, in any of the fifth to seventh aspects, the two concave mirrors include a first ellipsoidal mirror (40) and a second ellipsoidal mirror (50), and the first ellipsoidal mirror One of the two focal points of the surface mirror (second focal point F2) is placed at one of the two focal points (first focal point F3) of the second ellipsoidal mirror, and the light from the optical system is directed to the second focal point of the second ellipsoidal mirror. to the other of the two focal points (second focal point F4).

According to this aspect, in a fundus observation device using two ellipsoidal mirrors, it becomes possible to align the concave mirrors with high precision easily and at low cost.

In the ninth aspect of the embodiment, in the eighth aspect, the optical system includes a projection optical system (slit projection optical system 10, OCT optical system 100) that projects light from the light source, and a light receiving optical system (that receives the returned light). It is arranged at the other of the two focal points (first focus F1) of the slit light receiving optical system 20, OCT optical system 100) and the first ellipsoidal mirror, deflects the light from the light source, and guides the returned light to the light receiving optical system. A deflection member (hole mirror 30) is included.

According to this aspect, with a low cost and compact configuration, it is possible to secure a photographing angle of view exceeding 80 degrees with the optical system alone, and to use a shared optical system for the wide-angle optical path of the light and the optical path of the return light. It becomes possible to arrange it easily.

In a tenth aspect of the embodiment, in the eighth aspect, the optical system includes a deflection member (optical scanner 17), a projection optical system (slit projection optical system 10) that deflects and projects the light from the light source, and a return beam. A light receiving optical system (slit light receiving optical system 20) that receives light, an optical path coupling member (hole mirror 32) that optically couples the optical path of the projection optical system and the light path of the light receiving optical system, and a first ellipsoidal mirror. a reflecting member (reflecting mirror 31) disposed at the other of the two focal points (first focal point F1) and guiding light from a light source guided through an optical path combined by an optical path coupling member to a first ellipsoidal mirror; include.

According to this aspect, when there is not enough space to arrange an optical system near the second focal point of the first ellipsoidal mirror, it is possible to improve the degree of freedom in the arrangement of the projection optical system and the light receiving optical system. can.

<Others>
The embodiment shown above is only an example for implementing this invention. Those who wish to implement this invention can make arbitrary modifications, omissions, additions, etc. within the scope of the gist of this invention.

In some embodiments, a program is provided for causing a processor (computer) to execute each step of the method for controlling a fundus observation device described above. Such a program can be stored in any computer-readable non-transitory storage medium. Examples of this recording medium include semiconductor memory, optical disk, magneto-optical disk (CD-ROM/DVD-RAM/DVD-ROM/MO, etc.), magnetic storage medium (hard disk/floppy (registered trademark) disk/ZIP, etc.), etc. It is possible to use It is also possible to send and receive this program via a network such as the Internet or LAN.

1, 1a, 1b, 1c, 1d Fundus observation device 10 Slit projection optical system 17, 150 Optical scanner 20 Slit reception optical system 30, 32 Hole mirror 31 Reflection mirror 40 First ellipsoidal mirror 40A, 40B, 50A, 50B Protrusion 41 First holding member 41A, 41B, 51A, 51B Hole portion 50 Second ellipsoidal mirror 51 Second holding member 100 OCT optical system E Eye to be examined F1, F3 First focal point F2, F4 Second focal point P Fundus conjugate position Q Pupil conjugate position

Claims (10)

1. an optical system that projects light from a light source onto the fundus of the eye to be examined and receives return light from the fundus;
   two concave mirrors, each having a concave reflective surface, which guides the light from the optical system to the fundus and guides the returned light to the optical system;
   a holding member that holds the two concave mirrors;
   including;
   At least one of the two concave mirrors has a flange in which one of a fixed part and a fixed part is formed,
   The other of the fixing part and the fixed part is formed on the holding member,
   A fundus observation device, wherein the flange is held by the holding member while the fixed part is fixed by the fixing part.
2. The two concave mirrors are
   a first concave mirror having a first flange formed on a peripheral edge and having a concave first reflecting surface that reflects the light;
   a second concave mirror having a second flange formed on a peripheral edge thereof and having a concave second reflecting surface that guides the light reflected by the first concave mirror to the fundus;
   including;
   The fundus observation device according to claim 1, wherein the holding member holds the first flange and the second flange.
3. The fundus observation device according to claim 2, wherein the holding member holds the first flange and the second flange so that they are substantially parallel.
4. Any one of claims 1 to 3, wherein both ends of at least one of the two concave mirrors in the predetermined first direction have a shape cut by a plane intersecting the first direction. The fundus observation device described in .
5. The fundus observation device according to any one of claims 1 to 4, wherein at least one of the two concave mirrors is an ellipsoidal mirror.
6. The ellipsoidal mirror has a flange in which one of the fixed part and the fixed part is formed,
   On the surface of the flange, a straight line connecting a first projection point and a second projection point of the two focal points of the ellipsoidal mirror, and a straight line connecting the first projection point and one of the fixed part and the fixed part. The fundus observation device according to claim 5, wherein the oculi are orthogonal to each other.
7. The fixed part is a convex part,
   The fundus observation device according to any one of claims 1 to 6, wherein the fixing part is a recess or a hole.
8. The two concave mirrors include a first ellipsoidal mirror and a second ellipsoidal mirror,
   one of the two focal points of the first ellipsoidal mirror is located at one of the two focal points of the second ellipsoidal mirror,
   The fundus observation device according to any one of claims 5 to 7, wherein the light from the optical system is guided to the other of two focal points of the second ellipsoidal mirror.
9. The optical system is
   a projection optical system that projects light from the light source;
   a light receiving optical system that receives the returned light;
   a deflection member disposed at the other of the two focal points of the first ellipsoidal mirror, deflecting the light from the light source and guiding the returned light to the light receiving optical system;
   The fundus observation device according to claim 8, characterized in that it includes:
10. The optical system is
    a projection optical system that includes a deflection member and deflects and projects the light from the light source;
    a light receiving optical system that receives the returned light;
    an optical path coupling member that optically couples the optical path of the projection optical system and the optical path of the light receiving optical system;
    a reflecting member that is disposed at the other of the two focal points of the first ellipsoidal mirror and guides the light from the light source that has been guided through the optical path combined by the optical path coupling member to the first ellipsoidal mirror;
    The fundus observation device according to claim 8, characterized in that it includes:

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