JP5654271B2 - Ophthalmic equipment - Google Patents

Description

  The present invention relates to an ophthalmologic apparatus including a measurement optical system that measures wavefront aberration of an eye to be examined.

  2. Description of the Related Art Conventionally, an ophthalmometer is known in which measurement light is projected toward the fundus and the reflected light is received by a wavefront sensor to detect eye wavefront aberration. Furthermore, a fundus imaging apparatus is disclosed that controls a wavefront compensation device based on a detection result of a wavefront sensor and photographs a fundus image after wavefront compensation at a cell level. (For example, refer to Patent Document 1).

JP-T-2001-507258

  By the way, conventionally known ophthalmometers measure aberrations with the eye to be examined fixed in the front direction. Then, the present inventor tried to measure the aberration of the peripheral portion of the eye and to photograph the fundus in the above-mentioned eye fundus photographing apparatus with wavefront compensation by fixing the eye in the peripheral direction. However, the measurement light reaches a portion with high reflectance on the fundus (for example, the nipple), and the amount of light incident on the wavefront sensor becomes excessive, so that accurate aberration measurement cannot be performed. For this reason, a clear fundus image could not be obtained for peripheral photography.

  In view of the above problems, an object of the present invention is to provide an ophthalmologic apparatus that can suitably perform aberration measurement in the peripheral portion of the eye.

  In order to solve the above problems, the present invention is characterized by having the following configuration.

(1) A wavefront aberration detection optical system that projects measurement light toward the fundus of the subject's eye and receives the reflected light by a wavefront sensor, and a wavefront compensation device that is controlled based on a detection signal from the wavefront sensor An imaging optical system for capturing a fundus image of the eye to be examined in a state in which the wavefront aberration of the eye to be compensated is compensated, a setting unit that presets a luminance level according to the part to be imaged, and the setting unit Control means for controlling the wavefront aberration detection optical system so as to achieve the brightness level, and for controlling the brightness level of reflected light in the detection signal output from the wavefront sensor.
(2) In the ophthalmologic apparatus according to (1), the setting unit presets the luminance level according to a fixation lamp position.

  Aberration measurement at the periphery of the eye can be suitably performed.

  Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic diagram showing an optical system of the fundus imaging apparatus of the present embodiment. The fundus imaging apparatus of the present embodiment is broadly divided into a first fundus imaging optical system (hereinafter referred to as fundus imaging optical system) 100 that images the fundus of the subject's eye based on the reflected light from the fundus of the subject's eye. A wavefront aberration detection optical system having a wavefront sensor 73 for detecting the wavefront aberration of the eye to be examined, projecting measurement light onto the fundus of the eye to be examined, and receiving the reflected light as an index pattern image by the wavefront sensor 73 ( Hereinafter, it will be referred to as an aberration detection optical system.) 110, aberration correction units 10 and 72 arranged in the fundus imaging optical system 100 for correcting the aberration of the eye to be examined, and a fundus image obtained by the fundus imaging optical system 100 The second imaging unit 200 for obtaining an observation image of the fundus for designating the imaging position (hereinafter referred to as the first fundus image) (hereinafter referred to as the second fundus image), and the fixation of the eye E to be imaged. Misalignment due to visual movement Detecting a change over time, and a tracking unit (position detection unit) 300, to obtain the transfer position data. Here, the fundus imaging optical system 100 captures the fundus of the eye E with high resolution (high resolution) and high magnification. The aberration correction unit includes a diopter correction unit 10 for correcting low-order aberrations (diopter: for example, spherical power) of the eye to be examined, and a high-order aberration correction unit for correcting high-order aberrations of the eye to be examined. (Wavefront compensation device) 72 and fixation target presenting optical system 40 are roughly classified.

  The fundus imaging optical system 100 includes a first illumination optical system 100a that irradiates the eye E with illumination light (illumination light beam) to illuminate the fundus two-dimensionally, and reflected light (reflected light beam) of the illumination light irradiated on the fundus. And a first correction optical system 100b for obtaining a first fundus image and an aberration correction unit 72. The fundus imaging optical system 100 has, for example, a scanning laser ophthalmoscope configuration using a confocal optical system.

  The first illumination optical system 100a includes a light source 1 (first light source) that emits illumination light for illuminating the fundus and a scanning unit 20 that two-dimensionally scans the illumination light (spot light) on the fundus. The light source 1 emits near-infrared illumination light that is hardly visible to the eye to be examined. In the present embodiment, the light source 1 is an SLD (Super Luminescent Diode) light source having a wavelength of 840 nm. The light source may be any light source that emits spot light having a high convergence property, and may be, for example, a semiconductor laser.

  First, the first illumination optical system 100a will be described. In the optical path from the light source 1 to the fundus, a lens 2, a beam splitter 3, a polarizing plate 4, a lens 5, a beam splitter 71, a lens 6, a wavefront compensation device 72, a lens 7, and a beam splitter 75 are arranged. Further, the lens 8, the scanning unit 20, the dichroic mirror 46, the lens 9, a deflection unit 400 for correcting the scanning position of illumination light scanned two-dimensionally, a diopter correction unit 10 composed of two prisms, A beam splitter 90 that makes the optical path of the lens 11, the second photographing unit 200, etc. substantially coaxial with the first illumination optical system is disposed. The beam splitter 3 is a half mirror in this embodiment.

  Illumination light emitted from the light source 1 is converted into parallel light by the lens 2 and then converted into a light beam of only the S-polarized component by the polarizing plate 4 in this embodiment via the beam splitter 3. The illumination light that has passed through the polarizing plate 4 is once condensed by the lens 5, converted into a parallel light beam by the lens 6 through the beam splitter 71, and enters the wavefront compensation device 72. The illumination light reflected by the wavefront compensation device 72 is relayed by the lenses 7 and 8 and travels toward the scanning unit 20.

  The scanning unit 20 is configured to scan illumination light two-dimensionally on the fundus. Here, as illustrated, the illumination unit scans illumination light in the XY directions on the fundus. In the present embodiment, a resonant mirror serving as a deflecting member for deflecting and scanning illumination light in the horizontal direction (X direction) on the fundus, and scanning by deflecting the illumination light in a direction perpendicular to the horizontal scanning direction (Y direction). A galvanometer mirror serving as a deflection member and a drive unit for driving each mirror. The illumination light that has passed through the scanning unit 20 is condensed again by the lens 9 via the dichroic mirror 46. The deflecting unit 400 has a function of further deflecting the illumination light that has passed through the scanning unit 20 by a predetermined amount with respect to the horizontal direction and the vertical direction, and is configured by two galvanometer mirrors in the present embodiment. The illumination light that has passed through the deflection unit 400 is condensed on the fundus of the eye E through the diopter correction unit 10, the lens 11, and the beam splitter 90, and is scanned two-dimensionally on the fundus by the scanning unit 20. The diopter correction unit 10 includes a drive unit 10a, and one prism moves in the direction of the arrow shown in the figure, so that the optical path length can be changed and plays a role in diopter correction. The diopter correction unit 10 may be configured by a driving unit and a lens that can move in the optical axis direction by driving the driving unit. In addition, the beam splitter 90 is a dichroic mirror in the present embodiment, and reflects the light beam from the second imaging unit 200 and tracking unit 300 described later, and transmits the light beam from the light source 1 and the light source 76 described later. have. Note that the emission ends of the light source 1 and the light source 76 and the eye E to be examined are conjugate. In this way, the first illumination optical system that irradiates the fundus with illumination light two-dimensionally is formed.

  Next, the first photographing optical system 100b will be described. The first photographing optical system 100 has a common optical path from the beam splitter 90 to the beam splitter 3 described in the first illumination optical system 100a, and further includes a lens 51, a pinhole plate 52 placed at a position conjugate with the fundus, and a light collecting unit. An optical lens 53 and a light receiving element 54 are included. In this embodiment, the light receiving element 54 is an APD (avalanche photodiode).

  The reflected light from the fundus of the illumination light emitted from the light source 1 traces the first illumination optical system 100a in the reverse direction and is transmitted by the polarizing plate 4 only for S-polarized light, and then partially reflected by the beam splitter 3. Is reflected. This reflected light is focused on the pinhole of the pinhole plate 52 through the lens 51. The reflected light focused at the pinhole is received by the light receiving element 54 through the lens 53.

  In this way, the first photographing optical system 100b is formed. The processed image received by the first imaging optical system 100b becomes the first fundus image. The mirror swing angle (swing angle) in the scanning unit 20 is determined so that the angle of view of the fundus image (fundus image) acquired by the fundus imaging optical system 100 is a predetermined angle. Here, in order to observe and photograph a predetermined range of the fundus at a high magnification (here, observation at a cell level or the like), the angle of view is set to about 1 to 5 degrees. In this embodiment, the angle is 1.5 degrees. Although depending on the diopter of the eye to be examined, the imaging range of the first fundus image is about 500 μm square.

  Next, the second photographing unit 200 will be described. The second photographing unit 200 includes an illumination optical system that emits an illumination light beam from the light source 210 toward the fundus and a light receiving optical system that receives light reflected from the fundus by the light receiving element 251, and serves as a second fundus imaging optical system. Used. The second photographing unit 200 is used to acquire a fundus image (second fundus image) having a wider angle of view than the imaging optical system 100. Then, the fundus imaging optical system 100 emits an illumination light beam toward a certain range of the fundus image captured by the second fundus imaging optical system. The second fundus image is used as an image for position designation and position confirmation for obtaining the first fundus image having the narrow angle of view described above.

  The second imaging unit 200 for acquiring such a second fundus image only needs to be able to acquire the fundus image of the eye E to be examined in real time with a wide angle of view (for example, about 20 to 60 degrees). Therefore, the second imaging unit 200 can use an observation / imaging optical system of an existing fundus camera, an optical system of a scanning laser ophthalmoscope (SLO), and a control system.

  Next, the aberration detection optical system 110 will be described. As described above, the aberration detection optical system 110 has some optical elements on the optical path of the first illumination optical system 100a, and shares a part of the optical path with the first illumination optical system 100a. The aberration detection optical system 110 includes a wavefront sensor 73, a polarizing plate 74, a light source 76, a lens 77, a polarizing plate 78, and a lens 79. From the beam splitter 71 to the beam splitter 90 placed on the optical path of the first illumination optical system. These optical members are shared. The wavefront sensor 73 includes, for example, a microlens array composed of a number of microlenses and a two-dimensional imaging element 73a (two-dimensional light receiving element) for receiving a light beam that has passed through the microlens array. A light source 76 that is an aberration detection light source (third light source) is a light source that emits light in an infrared region different from that of the light source 1. In the present embodiment, the light source 76 uses a laser diode that emits laser light having a wavelength of 780 nm. The laser light emitted from the light source 76 is converted into a parallel light beam by the lens 77, and the polarization direction (P-polarized light) is orthogonal to the illumination light from the light source 1 by the polarizing plate 78, and the optical path of the first illumination optical system by the beam splitter 75. Led to. Note that there is a fundus conjugate position between the lenses 7 and 8, and the emission end of the light source 76 has a conjugate relationship with this fundus conjugate position. The beam splitter 75 is a half mirror in this embodiment. The polarizing plate 78 has a role of making the light of the third light source irradiated to the fundus a predetermined polarization direction, and has a role of a first polarizing means provided in the wavefront compensation unit.

  In this case, the measurement light of the aberration detection optical system 110 is irradiated to the fundus through a common optical path with the first illumination optical system 100a. Then, the measurement light irradiation position is changed in synchronization with the change of the irradiation position of the fundus illumination light beam.

  The laser beam reflected by the beam splitter 75 is condensed on the fundus of the eye E through the optical path of the first illumination optical system 100a. The laser beam reflected from the fundus is reflected by the wavefront compensation device 72 through each optical member of the first illumination optical system 100a, deviated from the optical path of the first illumination optical system 100a by the beam splitter 71, the lens 79, and S-polarized light. The light is guided to the wavefront sensor 73 through the polarizing plate 74 through which only the component passes. The polarizing plate 74 is a second polarization unit provided in the wavefront compensation unit, and blocks the polarization direction (P-polarized light) of the light of the third light source irradiated to the fundus and is polarized perpendicular to the polarization direction. It plays the role of transmitting the direction (S-polarized light) and guiding it to the wavefront sensor 73. Note that the beam splitter 71 transmits light (840 nm) having the wavelength of the light source 1 and reflects light (780 nm) having the wavelength of the light source 76 for detecting aberration. Accordingly, the wavefront sensor 73 detects light having an S-polarized component from the scattered light on the fundus of the irradiated laser light. In this way, light reflected by the cornea and the optical element is suppressed from being detected by the wavefront sensor 73. The scanning unit 20, the reflection surface of the wavefront compensation device 72, and the microlens array of the wavefront sensor 73 are substantially conjugate with the pupil of the eye to be examined. The light receiving surface of the wavefront sensor 73 is substantially conjugate with the fundus of the eye E. As the wavefront sensor 73, an element capable of detecting wavefront aberration including low-order aberration and high-order aberration, for example, a Hartmann Shack detector, a wavefront curvature sensor that detects a change in light intensity, or the like is used.

  The wavefront compensation device 72 is, for example, a liquid crystal spatial light modulator and uses a reflective LCOS (Liquid Crystal On Silicon) or the like. The wavefront compensation device 72 is disposed in the optical path of the fundus imaging optical system 100 and controls the wavefront of incident light to compensate for the wavefront aberration of the eye to be examined.

  In this embodiment, the wavefront compensation device 72 is a liquid crystal modulation element and uses a reflective LCOS (Liquid Crystal On Silicon) or the like, but is not limited thereto. Any reflective wavefront compensation device may be used. For example, a deformable mirror that is a form of MEMS (Micro Electro Mechanical Systems) may be used. Further, instead of a reflection type wavefront compensation device, a transmission type wavefront compensation device that transmits reflected light from the fundus and compensates for wavefront aberration can also be used.

  In the above description, a light source that emits illumination light having a wavelength different from that of the first light source is used as the aberration detection light source. However, the first light source may be used as the aberration detection light source.

  Note that the measurement light of the aberration detection optical system 100 is projected to the eye E via the scanning unit 20 and the deflection unit 400. For this reason, the irradiation position of the measurement light on the fundus is the same position as the high-magnification fundus observation light.

  In the present embodiment described above, the wavefront sensor and the wavefront compensation device are the pupil conjugate of the eye to be examined. However, the position may be a position that is substantially conjugate with a predetermined part of the anterior eye portion of the eye to be examined. There may be.

  The fixation target presenting optical system 40 includes a red light source 41 composed of seven LEDs and a relay lens 42, is reflected by the dichroic mirror 46, and is split from the lens 9 described in the first illumination optical system 100 a to the beam splitter 90. Share the optical path to The light beam from the light source 41 is collected on the fundus of the eye to be examined.

  The fixation target presentation optical system 40 is configured to be able to change the fixation target presentation position to a standard position for photographing the fundus central part and a peripheral position for photographing the fundus peripheral part. That is, as shown in FIG. 2, the light source 41a corresponding to the fixation target position 43a among the light sources 41 composed of seven LEDs is used when photographing the vicinity of the posterior pole portion of the fundus. This fixation target position 43a is set as a standard position. Then, fixation target positions 43b to 43g corresponding to the other light sources 41b to 41g are set as positions for peripheral photographing. The fixation position can be switched by a fixation position changeover switch (not shown), and the light source corresponding to the fixation position selected by the examiner is turned on.

  Next, a control system of the fundus imaging apparatus will be described. FIG. 3 is a block diagram showing a control system of the fundus imaging apparatus of the present embodiment. The control unit 80 that controls the entire apparatus includes a light source 1, a scanning unit 20, a fixation light source 41, a light receiving element 51, a wavefront compensation device 72, a wavefront sensor 73, a light source 76, a second photographing unit 200, a light source 210, and a light receiving unit. The element 251, the tracking unit 300, the deflection unit 400, the deflection unit 410, and the diopter correction unit 10 are connected. In addition, a memory 81, a control unit 82, an image processing unit 83, and a monitor 85 are connected. The image processing unit 83 forms, on the monitor 85, images of the fundus oculi having different angles of view, that is, a first fundus image and a second fundus image, based on signals received by the light receiving element 51 and the second imaging unit 200. The memory 81 stores various setting information and captured images. As the monitor 85, for example, a monitor of an external personal computer or a monitor provided in an apparatus can be considered. The fundus images (first fundus image and second fundus image) updated at a predetermined frame rate are displayed on the monitor 85. The frame rate is, for example, 10 to 100 Hz. In this way, the fundus image is displayed as a moving image. In the present embodiment, the control unit 80 also functions as a display control unit 80 of the monitor 85, a drive control unit of the deflection units 400 and 410, and an emission control unit such as the light sources 1, 41, and 76.

  The operation of the fundus imaging apparatus having the above configuration will be described. The examiner fixes the eye E using the fixation target, and aligns the apparatus with respect to the eye E using a joystick (not shown) or the like. At this time, the diopter correction unit 10 is driven by the operation of the control unit 82, and the diopter correction of the eye E is performed. In the alignment, the second fundus image by the second imaging unit 200 is displayed in a predetermined area of the monitor 85, and the examiner looks at the observation image (second fundus image) displayed on the observation screen frame of the monitor 85, Complete the alignment. After the alignment is completed, the examiner inputs a command signal for operating the tracking unit 300 using the control unit 82.

  Upon receiving the tracking start command signal, the control unit 80 drives the tracking unit 300 and the deflection units 400 and 410 to start tracking the eye E.

  When alignment is completed and a predetermined trigger signal is output by the examiner, diopter correction is performed by the control unit 80 using the diopter correction unit 10, and then wavefront detection (aberration detection necessary for aberration correction) is performed. )I do.

  Aberration detection is performed based on the detection result of the Hartmann image. When the measurement light from the light source 76 is projected onto the fundus and the reflected light passes through the lens array of the wavefront sensor 73 and is received by the two-dimensional image sensor 73a, a Hartmann image consisting of a set of a plurality of points is obtained. An image is taken on 73a. An aberration is detected based on the position of the point image of the Hartmann image and the interval between the point images. The initial setting of the amount of light emitted from the light source 76 and the sensitivity of the image sensor 73a is determined in advance by experiments or the like so that a good Hartmann image can be obtained in front fixation.

  4A is an example showing a low-magnification fundus image, and FIG. 4B is a diagram showing a luminance distribution (0 to 255 gradations) on the line R in FIG. 4A. That is, the nipple periphery has a higher reflectance than other fundus sites.

  FIGS. 5A and 5B are diagrams showing luminance distributions of the low-magnification fundus image, the Hartmann image, and the Hartmann image. FIG. 5A shows the fundus center photographing and FIG. 5B shows the teat photographing. A frame F represents a photographing region of a high-magnification fundus image.

  As shown in FIG. 5A, when the central part is photographed, the light source 41a is turned on and set to the fixation target position 43a. Then, the line of sight of the eye E is guided in the front direction. At this time, a Hartmann image 37 having a luminance suitable for aberration measurement is obtained. For example, the luminance peak 35 in the Hartmann image 37 is not saturated. It should be noted that almost the same Hartmann image can be obtained in photographing other than the nipple.

  As shown in FIG. 5B, when the nipple is photographed, the light source 43f is turned on for the right eye, and the light source 43c is turned on for the left eye. At this time, since the measurement light is projected onto the nipple with high reflectivity, the amount of the reflected light becomes excessive, and a Hartmann image 38 with saturated luminance is obtained. For example, the luminance peak 36 in the Hartmann image 38 is saturated. In this case, since the position of the Hartmann image 38 cannot be accurately detected, the measurement accuracy of the aberration is lowered.

  That is, when the irradiation position of the measurement light beam on the fundus is changed by the fixation target presenting optical system 40, the control unit 80 controls the aberration detection optical system 110 and outputs it from the wavefront sensor 73 in order to cope with this. The brightness level of reflected light in the detected signal is controlled.

<Oversaturation determination and light amount (gain) adjustment>
Hereinafter, the control of the luminance level of the reflected light will be specifically described. FIG. 6 is a flowchart showing an example of oversaturation determination and light amount (gain) adjustment. The control unit 80 detects luminance distribution information in the Hartmann image received by the image sensor 73a, and based on the detection result, whether or not the luminance level of the reflected light received by the wavefront sensor 73 exceeds a certain allowable level. Determine whether. Then, the control unit 80 controls the aberration detection optical system 110 based on the determination result, and adjusts the light projection amount of the light source 76 or the sensitivity (gain) of the image sensor 73 a of the wavefront sensor 73.

  I will explain more specifically. The controller 80 scans the Hartmann image acquired by the wavefront sensor 73 in a two-dimensional manner to measure the luminance value for each pixel in the Hartmann image, and based on the measurement result, determines the luminance distribution of the entire Hartmann image. To detect.

  Next, the control unit 80 detects a value having the highest luminance value in the luminance distribution of the entire Hartmann image as a peak value, and determines whether the peak value exceeds the threshold value S. Then, the light amount is adjusted based on the determination result.

  In the present embodiment, a threshold value S (in this embodiment, 80% brightness value at 255 gradations) is set as a brightness value that does not reach 100% brightness value and does not affect the aberration measurement. did. In this embodiment, the luminance value is set to 80% as the threshold value S. However, the present invention is not limited to this as long as the Hartmann image can be detected with high accuracy. For example, a luminance value of 100% may be set as the threshold value. In addition, a threshold value S is set in the vicinity of an intermediate value between the luminance value of the part having the lowest reflectance (luminance value at the macula) and the luminance value of the part having the highest reflectance (luminance value at the nipple). May be.

  Here, as illustrated in FIG. 5B, when the peak value 36 exceeds the threshold value S, the control unit 80 indicates that the brightness of the Hartmann image (reflected light) exceeds the allowable level (saturates. The aberration detection optical system 110 is controlled so that the brightness level of the reflected light is lowered. That is, the light amount of the light source 76 is decreased by a predetermined amount. Then, after reducing the amount of light, it is determined again whether the peak value 36 exceeds the threshold value S. As described above, the control unit 80 repeats the above control until the peak value 36 becomes equal to or less than the threshold value S.

  By such control, as shown in FIG. 7, the peak value 36 is below the threshold value S, and a Hartmann image 39 with appropriate luminance is acquired. Therefore, when the peak value 36 is equal to or less than the threshold value S, the control unit 80 determines that the brightness of the Hartmann image is at an allowable level and stops adjusting the light amount of the light source 76. Then, the control unit 80 detects the image position of the Hartmann image 39 and measures the wavefront aberration of the eye E.

  In addition, when the peak value 35 is equal to or less than the threshold value S from the beginning, the control unit 80 directly shifts to aberration measurement. In other words, if the reflectance is not high, the light amount adjustment corresponding to the supersaturation is not performed and the aberration is measured as usual.

<Aberration measurement>
The control unit 80 detects the wavefront aberration of the eye E based on the detection signal (detection result) of the Hartmann image in the wavefront sensor 73 and controls the wavefront compensation device 72. When wavefront aberration is compensated as described above and a predetermined trigger signal is output, a cell image of the fundus is captured as a moving image or a still image.

  With the configuration as described above, it is possible to change the light amount according to the imaging region on the fundus, so that accurate aberration measurement is possible even when imaging a portion with high reflectivity (for example, the nipple) on the fundus. It can be performed. As a result, a clear fundus image can be obtained for peripheral photographing.

  In addition, when determining whether the light quantity of the light source 76 is adjusted, it is not restricted to the said method. For example, it may be determined whether or not an integrated value obtained by integrating the luminance values for each pixel (the sum of the luminance values for each pixel) is within an allowable range. It may be determined whether the average value (weighted average of all luminances) when the sum is divided by the number of pixels is within an allowable range. That is, any criteria may be used as long as it is possible to determine whether or not the reflected light is an incident light quantity that affects the aberration measurement based on the secondary luminance distribution in the Hartmann image.

  In the present embodiment, the light amount is adjusted by adjusting the light source 76, but the present invention is not limited to this. For example, a light amount adjustment filter or an optical attenuator may be provided in the optical path from the light source 76 to the eye E. Further, the control unit 80 may control the wavefront sensor 73. For example, the sensitivity (gain) of the imaging signal output from the imaging element 73a of the wavefront sensor 73 may be adjusted. Further, the exposure time in the image sensor 73a, the number of Hartmann image additions, and the like may be controlled. The control unit 80 may combine the control of the light projecting system and the light receiving system.

  In addition to the above method, the amount of light emitted from the light source 76 or the gain of the wavefront sensor 73 is set in advance for each imaging region (measurement region), and the control unit 80 changes the setting according to the imaging region. May be. For example, a mode corresponding to each imaging region for imaging the fundus center and imaging the nipple periphery is provided. Then, the light amount and the fixation lamp position for each mode are preset.

  In this embodiment, the fixation direction is changed by changing the fixation target position to be lit, and the imaging region is changed. However, the present invention is not limited to this. For example, the present invention can be applied even when the irradiation position of the photographing light beam and the measurement light beam on the fundus is moved by the scanning unit 20. Further, the imaging region may be changed by using a tilt mechanism for moving the imaging apparatus main body with respect to the center of the pupil of the eye to be examined or a moving mechanism for the face support unit for driving the chin rest. When such a configuration is used, the changeable area when changing the shooting area becomes wider than when the shooting area is changed by changing the fixation target position.

  In the present invention, the amount of light is adjusted at the time of photographing a highly reflective part such as the nipple. However, the present invention is not limited to this. For example, the present invention can also be applied to photographing a part with little reflected light such as macula. In this case, a lower limit threshold value may be provided, and the projected light amount may be increased when the peak value of the light amount is equal to or less than the threshold value. In the determination of the luminance level, a lower limit threshold value corresponding to the macular region and an upper limit threshold value corresponding to the nipple may be set, and the light amount may be controlled when the allowable range is exceeded.

  In the above description, the fundus imaging optical system 100 receives the light beam reflected from the fundus of the eye to be examined through the confocal aperture disposed at a position substantially conjugate to the fundus of the eye to be examined, and confocals the fundus of the eye to be examined. Although a confocal optical system (SLO optical system) that captures a front image is used, the present invention is not limited to this (see, for example, JP 2001-507258 A).

  For example, a fundus camera optical system that captures a frontal image of the fundus of the subject's eye by receiving a light beam reflected from the fundus of the subject's eye with a two-dimensional image sensor. Further, it may be an optical interference optical system (OCT optical system) that captures a tomographic image of the eye to be inspected by receiving the light beam reflected from the fundus of the eye to be examined and the interference light by the reference light.

  In the above description, the fundus imaging apparatus has been described as an example. However, the present invention can be applied to any apparatus that measures the wavefront aberration of the eye E by changing the irradiation position of the measurement light beam on the fundus. is there. Thereby, the wavefront aberration of the eye E at the time of peripheral fixation can be suitably photographed.

  In addition, the measurement light is projected toward the fundus and the reflected light is received by the light receiving element to detect the eye state (for example, wavefront aberration, eye refractive power, diopter, axial length, focus state with respect to the fundus). The present invention can be applied to any ophthalmologic apparatus having a detection optical system. In such an apparatus, when the irradiation position of the measurement light beam on the fundus is changed, the detection optical system may be controlled to control the brightness level of the reflected light in the detection signal output from the light receiving element. In this way, regardless of the irradiation position on the fundus, it is possible to measure the eye characteristics and to measure the peripheral part of the eye. Of course, it may be a combined device of the above-described detection optical system and the fundus imaging optical system.

It is the schematic diagram which showed the optical system of the fundus imaging apparatus of this embodiment. It is the figure which showed the fixation target in this embodiment. It is the block diagram which showed the control system of the fundus imaging apparatus of this embodiment. It is a figure which shows the luminance distribution in a low-magnification fundus image and a fundus image. It is a figure which shows the luminance distribution of a low-magnification fundus image, a Hartmann image, and a Hartmann image. It is a flowchart which shows supersaturation determination and light quantity adjustment. It is a figure which shows the Hartmann image after light quantity adjustment, and its luminance distribution.

20 Scanning Unit 40 Fixation Target Presenting Optical System 72 Wavefront Compensation Device 73 Wavefront Sensor 80 Control Unit 85 Monitor 100 First Fundus Imaging Optical System 110 Wavefront Aberration Detection Optical System 200 Second Imaging Unit 300 Tracking Unit 400, 410 Deflection Unit

Claims (2)

A wavefront aberration detection optical system that projects measurement light toward the fundus of the subject's eye and receives the reflected light by a wavefront sensor;
An imaging optical system having a wavefront compensation device controlled based on a detection signal from the wavefront sensor and imaging a fundus image of the eye to be examined in a state in which the wavefront aberration of the eye to be examined is compensated;
Setting means for presetting the luminance level according to the part to be imaged ;
Control means for controlling the wavefront aberration detection optical system so as to be the brightness level preset by the setting means, and for controlling the brightness level of reflected light in the detection signal output from the wavefront sensor;
An ophthalmologic apparatus comprising: The ophthalmic device according to claim 1.
The ophthalmologic apparatus, wherein the setting means sets the luminance level in advance according to a fixation lamp position.

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