JPH08154924A - Retinal camera having measuring function - Google Patents

Abstract

PURPOSE: To provide a retinal camera having a measuring function which enables measuring of a content of oxygen of a blood stream of an artery at an arbitrary position with easier selection of the position of the artery from an retinal image taken by a TV camera to contribute to accurate diagnosis of a disease concerning a brain by a measurement of the content of oxygen in the blood stream of the artery very close to the brain. CONSTITUTION: A monochromatic TV camera 13 and a color TV camera 11 are arranged at an imaging conjugated position of a retinal photographing optical system and first and second interference filters 17 and 18 adapted to let passing light be sensitive to hemoglobin and oxidized hemoglobin respectively and an optical planar glass 19 are arranged on a disc-shaped filter frame 16. A stroboscope 14 emits light interlocking the rotation of a disc. During the emission of the stroboscope, the content of oxygen at a position indicated to a retinal image on a monitor by a mouse 38 is computed by a controller 36 from memory values of pixels of a first frame memory 31 which stores a retinal image by illumination light through the first interference filter 17 and a second frame memory 32 which stores the retinal image by illumination light through the second interference filter 18 and displayed on a monitor 37.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fundus camera having a function capable of measuring and displaying medically necessary numerical values during fundus photography, and more specifically, measuring the oxygen content rate of arterial blood flow in each part of the fundus. The present invention relates to a fundus camera having a function capable of performing.

[0002]

2. Description of the Related Art In recent years, fundus photography has become widely used in medical examinations because many useful medical findings such as arteriosclerosis and hypertension can be obtained. In this case, the main purpose is to make a qualitative judgment by looking at the condition of the blood vessels in the fundus from the photograph taken, and in order to make a more accurate diagnosis, the data obtained by analyzing the photographed fundus image should be used. I'm trying to do. For example, measuring the thickness of blood vessels in the fundus to be used as a material for diagnosing arteriosclerosis, and similarly measuring the meandering state of blood vessels in the fundus and the papilla diameter in the fundus to be used as a material for diagnosing diabetes. There is.

On the other hand, there is measurement of oxygen saturation (oxygen content) of arterial blood for diagnosis and monitoring of respiratory diseases, but it is necessary to directly measure the oxygen saturation without taking blood from a subject. The device described in Japanese Patent Application Laid-Open No. 50-128387 discloses an ear oximeter of an optical blood measuring device as a device that utilizes transmitted light passing through the auricle and transmits light through a fingertip. An example of an oximeter disclosed in Japanese Patent Application Laid-Open No. 50-143380 (see FIG. 2) that utilizes light is used, but in any case, blood that pulsates without the need for ischemia of the test area is used. This is done by detecting the transmitted light. At present, there is no one that can obtain numerical data for diagnosis directly from the fundus image.

[0004]

In the conventional measurement of the oxygen content of blood, since it is difficult to separate arterial blood, it is attempted to calculate it from the permeability of pulsating blood. In the case of, the one that uses the light transmitted through the fingertip is inaccurate as a diagnostic material because it is far from the brain, and the one transmitted by the auricle requires holding the earpiece and warming the ear. The inconvenience of such operations was unavoidable. The present invention has been made in view of the above points, from the fundus image by the television camera, it is possible to easily measure the oxygen content of blood at the position by selecting an arbitrary location of the artery, A fundus camera equipped with a measurement function that can increase the accuracy of diagnosis of a disease relating to the brain by measuring the oxygen content rate of arterial blood flow in a place extremely close to the brain and contribute to the diagnosis of the disease The purpose is to do.

[0005]

In order to achieve the above object, in a fundus camera having a measuring function of the present invention,
At least, in a fundus camera including an observation illumination unit, a photographing illumination unit, a fundus photographing optical system, and a monitor, a fundus photographing optical system includes a monochrome TV camera and a color TV camera at an image formation conjugate position where a fundus image is formed, The photographic illuminating means is provided with filters that include a pair of first and second interference filters that are responsive to passing light to hemoglobin and oxyhemoglobin, respectively, so as to be switchably inserted into the illumination optical path, and through the first interference filter. A first frame memory that stores a fundus image by illumination light, a second frame memory that also stores a fundus image by illumination light that passes through a second interference filter, and a pixel of the first and second frame memories. It is configured to have a means for calculating the oxygen content rate of each part of the fundus from the memory value.

As a means for calculating the oxygen content rate, a means such as a mouse or a touch pen for indicating an arbitrary position of the fundus image on the monitor screen is attached, and the oxygen content rate at the indicated position is calculated and displayed. Target.

The combination of wavelength bands of light rays passing through the pair of interference filters is 880 mm and 665 mm, or 90
Either 0 mm and 630 mm or 805 mm and 630 mm should be used.

The filters including the pair of interference filters are arranged in a predetermined position on the disk when they are switched and inserted in the illumination optical path to the eye to be inspected, and are interlocked with the rotation of the disk. Then, it is advantageous that the strobe light source emits light when the respective axes of the filters match the illumination optical axis of the strobe light source.

[0009]

According to the present invention, by adopting the structure described in claim 1, in photographing the fundus of the eye to be inspected, the fundus photographing optical system for observing the alignment of the fundus of the eye by the observation illumination means. When the fundus of the eye to be inspected is irradiated through the optical axis of, the reflected light from the fundus enters the monochrome television camera and the color television camera arranged at the image formation conjugate position via the optical path of the fundus photographing optical system. At this time, the fundus image formed on the light receiving surface of the monochrome TV camera is displayed on the monitor screen using infrared light that does not cause the subject to feel glare, and this image is used to perform alignment including the focusing of the fundus camera. I do. Next, a pair of first and second interference filters in which the passing light is sensitive to hemoglobin and oxyhemoglobin, respectively, and another filter (optical flat glass, etc.) that does not absorb color are inserted into the switching illumination optical path, and each filter is inserted. When illuminating the fundus with illumination light from a strobe etc. during insertion, the reflected light from the fundus sensitizes the passing light to the hemoglobin through the monochrome television camera at the imaging position of the fundus photographing optical system.
The fundus image by the illumination light that has passed through the interference filter of No. 2 is in the first frame memory, and the fundus image by the illumination light that has passed through the second interference filter in which the passing light is sensitive to oxygenated hemoglobin is the second
The image of the fundus of the eye that is stored in the frame memory of No. 2 and is transmitted through the filter that does not absorb color such as the optical flat glass is displayed on the monitor screen through the color television camera.

Then, the calculating means of the camera can calculate the ratio of the memory values of the pixels at the same position in the first and second frame memories to obtain the oxygen content rate of each part of the fundus. Display with fundus image,
It can be displayed on another display device.

When calculating the oxygen content rate in the fundus image, the means for calculating the oxygen content rate should be provided with means for indicating an arbitrary position of the fundus image on the monitor screen such as a mouse, and the oxygen content rate at the indicated position can be calculated. By calculating and displaying, it is possible to easily select an artery at an arbitrary position of the fundus image and know the oxygen content rate of the blood flow.

The wavelength band of light passing through the pair of interference filters is 880 mm and 665 mm, or 900 mm and 630 m.
By using m, or either 805 mm or 630 mm, the oxygen content can be measured efficiently.

When the filters including the pair of interference filters are inserted into the optical path of the photographing illumination, the filters are arranged at a predetermined position on the disk and each of the filters is linked with the rotation of the disk. When the axis center of the is aligned with the illumination light axis of the strobe light source, the strobe light source emits light so that the illumination light can be switched in a very short time to photograph the fundus, and the oxygen content rate can be calculated. The oxygen content rate of the arterial blood flow in each part of the fundus can be accurately calculated and calculated by almost eliminating the time difference between the fundus images stored in the first and second frame memories.

[0014]

Embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a block diagram of the above-described embodiment, and FIG. 2 is a flowchart showing a procedure for calculating and displaying the oxygen content and color data at the indicated position of the fundus image.

In FIG. 1, an observation illumination means for illuminating the position of the fundus of the eye E to be examined during observation, a photographing illumination means for illuminating the fundus during photographing, and a fundus photographing optical for photographing the fundus. System, a monitor for displaying a fundus image,
A photographic system 1 including a plurality of memories for storing a fundus image illuminated by switching and illuminating the illuminating light by the illuminating means, and an observing illuminating means, a photographic illuminating means, and a retinal photographing optical system is provided in an X.Y.
A fundus camera with a joystick for movement in the Z direction is shown.

As a light source for illuminating the fundus of the eyeball E, an illumination lamp 28 is provided for illuminating the vertical / horizontal position of the camera, the working distance, and the in-focus state when viewed on a monitor screen, which will be described later. The strobe discharge tube 14 for calculating the ratio and for illuminating when viewing the fundus color image on the monitor screen, the focusing position of the light emitted from the strobe discharge tube 14 by the condenser lenses 15 and 21 and the observation illumination lamp 28. The strobe discharge tube 14 is arranged so that the emitted light is focused at the same focusing position by the condenser lenses 29 and 21.
Light (visible light) passes through any of the filters 17, 18 and 19 and the infrared light reflecting visible light transmitting mirror 20, while the light (visible light) emitted by the observation illumination lamp 28 passes through the visible light cut filter 30. Only infrared light that passes through the mirror 20
Are arranged so as to be focused at the positions of the circular slits 22, respectively.

The light passing through the circular slit 22 is bent at the optical path reflected by the mirror 23 and focused on the illumination optical axis 24 at the position of the perforated mirror 4 through the flat glass 25, the condenser lenses 26 and 27. The image of the circular slit is formed on the perforated mirror 4, reflected by the mirror 4, passes through the objective lens 3 of the fundus photographing optical system described later, and the pupil position of the eyeball E (the position of the iris diaphragm). The light is focused on to illuminate the retina surface of the fundus E of the eyeball E. The filament of the illumination lamp 28 or the discharge part of the strobe discharge tube 14 and the positions of the circular slit 22, the perforated mirror 4 and the iris diaphragm of the eye E have a conjugate relationship. That is, the circular slit 2 is formed on the eye to be examined.
Illumination light enters only through the ring passage 2 and illuminates the fundus through the pupil. At this time, the reflected light from the center of the cornea is cut off and does not directly enter the objective lens.

Among the above three filters, the interference filter 17 has a wavelength band of 880 mm for passing light because passing light is sensitive to hemoglobin (hemoglobin) in blood (that is, it is not sensitive to oxygen saturation). Therefore, the interference filter 18 has a wavelength band of the transmitted light of 6 as the transmitted light is sensitive to oxygenated hemoglobin (strongly sensitive to oxygen saturation).
It is 65 mm. As a result, when the fundus is illuminated by the illumination light that has passed through the equal interference filter, hemoglobin (Hb) and oxyhemoglobin (HbO ₂ ) in the bloodstream flowing in the artery are
It is possible to obtain a fundus image having a difference in absorbance corresponding to The wavelength band of the interference filter corresponding to hemoglobin and oxyhemoglobin is changed to a combination of 880 mm and 665 mm, and 900 mm and 630 mm or 805 mm and 630 are used.
It can be changed to a combination of mm. In addition, the filter 19
Is an optical flat glass that allows the strobe light to pass through.

The filters 17, 18 and 19 are arranged at predetermined positions on the disc-shaped holding frame 16, and the base 40
The holding frame is rapidly rotated by operating the upper operation switch, and the axes of the filters 17, 18 and 19 are linked to the rotation of the disc-shaped holding frame 16 so that the illumination light of the strobe light source 14 is emitted. When aligned with the axis, the strobe light source 14 is adapted to intermittently emit light in a multi-strobe manner. As a result, the time difference between fundus images stored in the frame memories 31 and 32 for calculating the oxygen content rate, which will be described later, can be minimized and the oxygen content rate of the fundus image (each portion) can be accurately calculated and measured.

In the optical system for photographing the fundus, on the optical axis 2 of the fundus photographing optical system which should be located on the eye axis, a position is formed facing the eye E to form an optical pupil in the pupil portion of the eye E. The objective lens 3 is provided. Then, a perforated mirror 4, a focus lens 5, an infrared light reflecting / visible light transmitting mirror 6 are sequentially arranged at a predetermined position on the optical axis 2, and a color television camera 11 is arranged on the optical axis 2, and A monochrome television camera 13 is arranged on the optical axis 2'of the side where the optical path is bent by the infrared light reflecting / visible light transmitting mirror 6 so as to form the same screen at the image forming conjugate position. . That is, the color television camera 11 is provided with an optical path branching prism 7 on the optical axis 2 for branching the optical path in three directions including the optical axis, and the red filter 7 is provided on each of the light exit end surfaces branched in three directions.
_R , green filter 7 _G , blue filter 7 _B are attached,
Three CCD light receiving surfaces 8, 9 and 10 facing the filter
Are arranged so that each fundus image of three colors of R, G, B (red, green, blue) is formed into a husband image.

On the CCD light receiving surface 12 of the monochrome television camera 13, two frame memories for receiving the image signals from the television camera, that is, the interference filter 17 (88).
First frame memory 31 for storing a fundus image (a fundus image sensitive to hemoglobin) by illumination light through 0 mm)
And a second frame memory 32 for storing a fundus image (fundus image sensitive to oxidized hefmoglobin) by illumination light through the interference filter 18 (665 mm) are connected, while the red filter 7 _R of the color television camera 11 is connected. The third frame memory 33 is provided on the light-receiving surface 8 via the green filter 7 _G , the fourth frame memory 34 is provided on the light-receiving surface 9 via the green filter 7 _G, and the light-receiving surface 1 via the blue filter 7 _B is also provided.
A fifth frame memory 35 is connected to 0, five frame memories are connected to a control circuit 36, and a fundus image is displayed on a monitor 37 connected to the control circuit 36.

The monochrome television camera 13 is capable of capturing a fundus image by infrared light, and cuts visible light from the illumination lamp 28 at the time of alignment such as alignment of the photographing optical system, alignment of working distance, and focusing. Filter 30
A fundus image by the illumination light of the infrared light through the image is formed on the light receiving surface 12 of the monochrome television camera 13, and the fundus image signal that has passed through the frame memories 31 and 32 is monitored by the monitor 37 via the control circuit 36. It is possible to display the fundus image on the screen and to position the photographing system 1 while visually observing the image.

X, Y, and Y for the subject's eye E of the imaging system 1
The movement in the Z direction is performed by operating the joystick 39 on the base 40 on which the photographing system 1 is mounted. That is, the photographing is provided with a fundus illuminating optical system having the illumination lamp 28 which is the observing and illuminating means of the fundus and the strobe light source 14 which is the photographing illuminating means, and a retinal photographing optical system having the two TV cameras 11 and 12 in the housing. The system 1 uses the joystick 39 for manual operation to move the X, Y, and
It is provided so as to be movable in the Z direction, and the photographing system 1 is moved by operating the joystick 39 to perform alignment and working distance adjustment of the fundus photographing optical system with respect to the eye E to be inspected while checking on the monitor 37. Is able to. The focusing of the photographic optical system is performed by stopping the movement of the photographic system 1 after alignment and working distance adjustment, and then operating a push button or the like to move the focus lens 5 of the fundus photographic optical system by means not shown. The focus state can be confirmed on the screen of the monitor 37.

After the imaging system 1 is aligned with the eye E to be inspected in this manner, a color image of the fundus image and a flow through the artery of the fundus are operated by a push button or a key operation attached to the base 40. The oxygen content of the bloodstream can be calculated. That is, when the disc-shaped holding frame 16 provided with the filters is rotated by a push button or a key operation, the first frame memory 31 receives the illumination light from the strobe light source 14 that emits light in synchronization with The fundus image sensitive to hemoglobin by the illumination light passed through the interference filter 17, and the fundus image sensitive to oxygenated hemoglobin caused by the illumination light passed through the interference filter 18 are stored in the second frame memory 32. Is the red fundus image that has passed through the red filter 7 _R due to the illumination light that has passed through the filter 19 of the optical flat glass, and the fourth frame memory 34 is also the green fundus image that has similarly passed through the green filter 7 _G. In the fifth frame memory 35, the blue fundus image that has similarly passed through the blue filter 7 _B is stored.

The control circuit 36 is provided with means for obtaining the ratio of the memory values of the pixels at the same position of the fundus image in the first frame memory 31 and the second frame memory 32 and calculating the oxygen content rate at that position. In this embodiment, the mouse 38 connected to the control circuit 36 is operated to move the cursor on the monitor screen to select and instruct an artery at an arbitrary position in the fundus image, which will be described later. Is determined as a specific pixel in the first and second frame memories 31 and 32, and is calculated as the oxygen content rate of the arterial blood flow at that pixel.

Further, in the control circuit 36, R (red) and G stored in the third frame memory 33, the fourth frame memory 34, and the fifth frame memory 35, respectively.
The signals of the fundus image of the three primary colors of (green) and B (blue) are taken in, combined into a color image, and the fundus image in color is displayed on the screen of the monitor 37. And the color information at the position can be calculated from the memory value of the pixel at the same position in the third, fourth, and fifth frame memories 33, 34, and 35. . The calculation of this color information is
In the control circuit 36, by substituting the values of R, G, and B at the same position in the third to fifth frame memories into the following equation, Y, R− as the “Y.
Y, BY are set. Y = 0.3R + 0.59G + 0.11B R−Y = 0.7R−0.59G−0.11B B−Y = −0.3R−0.59G + 0.89B In this way, R, which is the basis of the color video signal. , G, B
"Y. color difference signal" obtained by using the signals, that is, Y and R
By using the three signals of -Y and BY, there is an advantage that RY and BY are 0 when there is no color or there is a place without color, and the number of signals decreases.

For the oxygen content and color information, a specific pixel of each frame memory is determined by operating the mouse 38 to move the cursor on the monitor screen to indicate an arbitrary position of the fundus image. It is possible to calculate the oxygen content and color information at the pixel, that is, at the position, and display the information on the monitor screen. The display of the oxygen content and the color information at the arbitrary position of the fundus image calculated by the arithmetic circuit 36 may be performed not by the monitor 37 but by a printer or the like. Also,
A touch pen may be used instead of the cursor to indicate the arbitrary position.

Next, the operation procedure of the fundus camera having the measuring function according to the present invention will be described with reference to the flowchart shown in FIG. First, the power is turned on, and the operation button on the base 40 of the fundus camera in the standby state is operated to turn on the illumination lamp 28 to irradiate the fundus of the eye E with infrared rays, and the fundus image by the reflected light. While looking at the screen of the monitor 37, the joystick 39 is operated to move the imaging system 1 in the X, Y, and Z directions with respect to the eye E to be aligned so that the papilla or the like of the fundus of the eye comes to a predetermined position. After adjusting the working distance between the photographic optical system and the pupil so that the brightness becomes uniform and stopping the movement of the photographic system 1, the focusing knob or the like is operated to move the focus lens 5 onto the optical axis 2 thereof. Then, the focus of the fundus is confirmed on the monitor 37, and the alignment of the photographing system 1 of the fundus camera with respect to the eye E is completed.

Next, by pressing the photographing button on the base 40, the illumination lamp 28 is turned off, the disc-shaped film holding frame 16 is rapidly rotated, and the axial centers of the filters 17, 18 and 19 are the strobe light source 14. The strobe light source 14 emits light in a matting strobe shape in accordance with the illumination optical axis of
The hemoglobin-sensitive fundus image of the fundus blood flow of the eye E to be inspected is in the first frame memory 31, the fundus image also sensitive to oxygenated hemoglobin is in the second frame memory 32, and the red fundus image of the eye E is in the third. The frame memory 33 stores the green fundus image in the fourth frame memory 34, and the blue fundus image stores in the fifth frame memory 35. The photographic data stored in the memory is taken into the control circuit 36.

In the control circuit 36, the fetched R
The signals of the (red), G (green), and B (blue) fundus images are combined to display a color fundus image on the monitor 37. Next, the mouse 38 instructs the contents of the plan such as the oxygen content rate or the color information, and the mouse is moved to move the cursor to the measurement position of the fundus image on the monitor screen to instruct the measurement position.

As a result, the control circuit 36 calculates the oxygen content at the indicated position, that is, the oxygen content of the arterial blood flow at the selected indicated position and the color data, and the measured value is displayed on the monitor 37. Next, by sequentially converting and instructing the required pointing position, the oxygen content and color information of each part of the fundus can be measured and displayed on the monitor. The oxygen content,
Depending on the circuit configuration of the control circuit 36, the display mode of each measured value of the color information is such that, in the case of an oxygen content rate, in addition to the oxygen content rate at an arbitrarily designated position, the average oxygen content of blood flow in the entire artery of the fundus image is included. It is also possible to display the rate, and further to display the same oxygen content portion in a contour line, and the display mode of the color information can be arbitrarily selected such as numerical value or graph display. Also,
In the above embodiment, when the color signal is obtained from the color television camera, the signals of R, G, B are obtained and processed, but it goes without saying that a signal system other than R, G, B may be used. It is possible and various modifications can be made without departing from the gist of the present invention.

[0032]

According to the fundus camera having the measuring function of the present invention as set forth in claim 1, the fundus camera having the monitor is provided with a means for calculating the oxygen content rate of each part of the fundus of the eye to be inspected. The oxygen content of the selected artery in each part of the fundus can be measured, and the oxygen content can be displayed on the monitor together with the fundus image or can be displayed on another display device. Therefore, the state of the oxygen content rate of the arterial blood flow very close to the brain can be easily known, the accuracy of the diagnosis of diseases relating to the brain can be increased, and the fundus camera that can contribute to the diagnosis of the diseases can be improved. Can be provided.

According to the second aspect of the present invention, it is possible to easily calculate and display the oxygen content at the indicated position by using the means for indicating an arbitrary position on the monitor screen of the fundus camera.

According to the third aspect of the present invention, when the oxygen content of each part of the fundus of the eye is calculated and measured by the fundus camera, hemoglobin can be efficiently and efficiently specified by specifying the wavelength band of the light beam passing through the pair of interference filters. By obtaining a fundus image sensitive to and a fundus image sensitive to oxygenated hemoglobin, the oxygen content in each part of the fundus can be easily calculated and measured.

According to the fourth aspect of the invention, in the fundus camera, the switching insertion of the filters into the illumination optical path of the strobe light source is interlocked with the rotation of the disk in which the filters are arranged, and each axis of the filters is switched. When the heart matches the illumination optical axis of the strobe light source, the strobe light source is made to emit light, so the time difference between the fundus image data stored in the frame memory for calculating the oxygen content rate is minimized as accurately as possible. The oxygen content in each part can be calculated and measured.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an embodiment of the present invention,

FIG. 2 is a flowchart showing a procedure for measuring and displaying oxygen content and color data at an arbitrary position on the fundus.

[Explanation of symbols]

1 ... Imaging system, 2 ... Fundus imaging optical system optical axis, 3 ... Objective lens, 4 ... Perforated mirror, 5 ... Focus lens,
6 ... Infrared light reflecting visible light transmitting mirror, 7 ... Optical path branching prism, 8 ... CCD light receiving surface (for red image), 9 ... C
CD light receiving surface (for green image), 10 ... CCD light receiving surface (for blue image), 11 ... Color television camera, 12 ... C
CD light receiving surface, 13 ... Monochrome TV camera, 14 ...
Strobe discharge tube, 17 ... Interference filter (880mm),
18 ... Interference filter (665 mm), 19 ... Optical flat glass, 22 ... Circular slit, 28 ... Illumination lamp,
30 ... Visible light cut filter, 31 ... First frame memory, 32 ... Second frame memory, 33 ... Third frame memory, 34 ... Fourth frame memory, 35 ... Fifth
Frame memory, 36 ... Control circuit, 37 ... Monitor,
38 ... Mouse, 39 ... Joystick, E ... Eye to be examined.

Claims (4)

[Claims] 1. A fundus camera including at least observation illumination means, photographing illumination means, a fundus photographing optical system, and a monitor,
The fundus photographing optical system is provided with a monochrome television camera and a color television camera at the image forming conjugate position, and the photographing illumination means is sensitive to the passing light to hemoglobin and oxyhemoglobin, respectively.
A first frame memory for storing a filter including a second pair of interference filters so as to be switchably inserted in an illumination optical path, for storing a fundus image by the illumination light through the first interference filter, and a second interference likewise. A second frame memory for storing a fundus image by the illumination light through the filter;
A fundus camera having a measuring function, comprising means for calculating an oxygen content rate of each part of the fundus from a memory value of a pixel of the second frame memory. 2. The means for calculating the oxygen content is provided with means for designating an arbitrary position of the fundus image on the monitor screen, and the oxygen content at the designated position is calculated and displayed. A fundus camera having the measurement function according to claim 1. 3. A fundus camera having a measuring function according to claim 1, wherein the wavelength band of light passing through the pair of interference filters is either 880 nm and 665 nm, 900 nm and 630 nm, or 805 nm and 630 nm. 4. A filter including a pair of interference filters,
The strobe light source is arranged at a predetermined position on the disc, and the strobe light source emits light when the axes of the filters are aligned with the illumination optical axis of the strobe light source in association with the rotation of the disc. A fundus camera having the measuring function according to claim 1, 2 or 3.