JP7124270B2 - ophthalmic imaging equipment - Google Patents

Description

The present disclosure relates to an ophthalmologic imaging apparatus that captures a tomographic image of an eye to be examined.

An optical coherence tomography (OCT) using low-coherent light is known as an ophthalmologic imaging apparatus that captures a tomographic image of an eye to be examined (see Patent Document 1).

JP 2008-29467 A

An optical tomography interferometer (OCT device) divides light emitted from a light source into measurement light and reference light, and irradiates the divided measurement light onto an eye to be examined (for example, fundus). However, there have been cases where the measurement light irradiated to the eye to be inspected is obstructed by the eyelid of the eye to be inspected, opacity or edema caused by a disease such as cataract, and a good tomographic image cannot be obtained.

A technical problem of the present disclosure is to provide an ophthalmologic imaging apparatus capable of acquiring a satisfactory tomographic image of the fundus of an eye to be examined in view of the above-described conventional technology.

In order to solve the above problems, the present disclosure is characterized by having the following configurations.

(1) An ophthalmologic imaging apparatus according to a first aspect of the present disclosure has an OCT optical system that detects an OCT signal from measurement light and reference light irradiated to the fundus of an eye to be examined, and processes the OCT signal to An ophthalmologic imaging apparatus for acquiring OCT data for optometry, which is a profile showing the distribution of the measurement light in the OCT optical system, the profile showing the distribution of the measurement light in the OCT optical system , the anterior segment of the measurement light irradiated toward the fundus of the eye to be examined. changing means for changing the profile indicating the distribution of the measurement light on the route from the to the fundus, and the plurality of temporary imaging firsts having different distributions of the measurement light on the route from the anterior segment to the fundus by the changing means obtaining means for obtaining first OCT data for each of the plurality of first profiles by irradiating the measurement light to the irradiation position set on the fundus of the eye to be examined in a state where the profile has been changed, and means acquires a transmittance distribution of return light with respect to the fundus of the subject eye from the plurality of first OCT data acquired by the acquisition means; to the fundus oculi, the distribution of the measurement light on the path from the to the fundus is changed to a new second profile different from the first profile. It is characterized by irradiating the irradiation position with the measurement light and acquiring the second OCT data.
(2) An ophthalmologic imaging method according to a second aspect of the present disclosure includes an OCT optical system that detects an OCT signal from measurement light and reference light irradiated to the fundus of a subject's eye, and processes the OCT signal to An ophthalmologic imaging method for acquiring OCT data for optometry, wherein a profile showing the distribution of the measurement light in the OCT optical system , the anterior ocular segment of the measurement light irradiated toward the fundus of the eye to be examined The distribution of the measurement light in the path from the anterior segment to the fundus is changed to a plurality of first profiles for provisional imaging, which are different from each other, by the changing means for changing the profile indicating the distribution of the measurement light in the path from the to the fundus. a first obtaining step of obtaining first OCT data of each of the plurality of first profiles by irradiating the measurement light onto an irradiation position set on the eye to be inspected, and a first obtaining step obtained by the first obtaining step A transmittance distribution of return light to the fundus of the subject's eye is obtained from a plurality of the first OCT data, and based on the transmittance distribution, a profile for main imaging is obtained as a profile for the measurement light on the path from the anterior segment to the fundus . a changing step of changing the distribution to a new second profile different from the first profile; and in the state changed to the second profile by the changing step, directing the measurement light to the irradiation position of the fundus of the subject's eye. and a second acquisition step of irradiating and acquiring second OCT data.

1 is an external configuration diagram of an ophthalmologic imaging apparatus according to an embodiment; FIG. 1 is a schematic configuration diagram showing an optical system and a control system of an ophthalmologic imaging apparatus according to the present embodiment, showing an optical arrangement during fundus imaging; FIG. FIG. 2 is a schematic configuration diagram showing the optical system and control system of the ophthalmologic imaging apparatus according to the present embodiment, showing the optical arrangement during imaging of the anterior segment. It is a figure which expands and shows a scanning part. 4 is a flowchart for explaining control operations; It is a figure which shows the anterior-segment observation image of a to-be-tested eye. It is a figure explaining DMD. FIG. 4 is a diagram showing the relationship between DMD and first profile; It is a figure explaining transmittance|permeability distribution. It is a figure explaining a 2nd profile. It is a figure which shows the modification example in the optical system of an ophthalmologic imaging device.

<Overview>
One exemplary embodiment will now be described with reference to the drawings. 1 to 10 are diagrams for explaining an ophthalmologic imaging apparatus according to this embodiment. In this embodiment, the horizontal direction of the eye to be examined is the X direction, the vertical direction is the Y direction, and the axial direction is the Z direction. The surface direction of the fundus may be considered as the XY direction. The items classified by <> below can be used independently or in association with each other.

It should be noted that the present disclosure is not limited to the apparatus described in this example. For example, terminal control software (program) that performs the functions of the following embodiments is supplied to a system or device via a network or various storage media, and a control device (eg, CPU, etc.) of the system or device reads the program. It is also possible to execute

For example, the ophthalmologic imaging apparatus (e.g., ophthalmic imaging apparatus 1) in the present embodiment has an OCT optical system (e.g., OCT optical system 2), and obtains OCT data of the subject's eye by processing OCT signals. For example, the OCT optical system (OCT device) may be based on Fourier domain optical coherence tomography (FD-OCT). For example, spectral domain OCT (SD-OCT) and wavelength sweeping OCT (SS-OCT) may be used as FD-OCT. Also, for example, the OCT device may be based on time domain OCT (TD-OCT). Note that, for example, the technology of the present disclosure includes standard OCT for detecting the reflection intensity of the subject, OCT angiography (for example, Doppler OCT) for detecting motion contrast data of the subject, polarization-sensitive OCT ( It may be applied in PS-OCT: Polarization Sensitive OCT) and the like. It may also be applied in multi-function OCT in which standard OCT and PS-OCT are combined.

<OCT optical system>
For example, the OCT optical system detects OCT signals from measurement light and reference light that are applied to the subject's eye. For example, the OCT optical system may have a configuration relating to an interferometer for obtaining a tomographic image of the subject using the OCT principle. For example, the OCT optical system includes a light source (e.g., light source 11), a splitter (e.g., coupler 15), a combiner (e.g., coupler 15), a detector (e.g., detector 40), a reference optical system ( For example, a reference optical system 30) may be provided.

For example, a splitter may split the light from the light source into measurement light and reference light. For example, the combiner may combine (interfere) the measurement light and the reference light. For example, the divider and combiner may be combined. Also, for example, the divider and combiner may be provided separately. For example, the splitter and combiner may be beam splitters, half mirrors, fiber couplers, circulators, or the like. For example, the detector may receive interference signal light caused by interference between the measurement light and the reference light. For example, the reference optics may have a configuration for causing the reference light to travel within the device and interfere with the measurement light.

For example, the OCT optical system acquires OCT data of the subject's eye by processing the OCT signal. In addition, the OCT optical system switches the depth zone of the eye to be imaged, and the first position corresponding to the first depth zone of the eye to be inspected (for example, the anterior segment of the eye to be inspected) and the second depth zone of the eye to be inspected (For example, the second position corresponding to the fundus of the eye to be examined, etc.) may be configured to acquire OCT data.

<Measurement optical system>
For example, the measurement optical system (for example, the measurement optical system 20) may be configured to guide measurement light to the subject's eye. For example, the measurement optical system may include a scanning section (optical scanner) (for example, scanning section 24). For example, the scanning unit scans the measurement light over a first position corresponding to a first depth zone of the subject's eye. Also, for example, the scanning unit scans the measurement light at a second position corresponding to a second depth zone of the subject's eye. For example, the scanning unit may include two optical scanners (eg, galvanomirror 241 and galvanomirror 242) that deflect measurement light in different directions. For example, the optical scanner included in the scanning unit may be a MEMS scanner, a resonant scanner, a reflective scanner such as a polygon mirror, or an acoustooptic device. That is, the optical scanner included in the scanning section may be any scanner capable of deflecting the measurement light.

<OCT data>
For example, the OCT data includes tomographic image data indicating reflection intensity characteristics of the eye to be examined, OCT angio image data of the eye to be examined (for example, OCT motion contrast image data), Doppler OCT image data indicating Doppler characteristics of the eye to be examined, It may be at least one of polarization characteristic image data indicating polarization characteristics, and the like. Each data may be data of a generated image, or may be signal data before the image is generated.

For example, the tomographic image data may be A-scan tomographic image data. Further, for example, the tomographic image data may be B-scan tomographic image data. Note that, for example, the B-scan tomographic image data is tomographic image data acquired by scanning the measurement light along a scanning line (transverse position) in one of the XY directions (for example, the X direction). good too. Further, for example, the tomographic image data may be three-dimensional tomographic image data. Note that, for example, the three-dimensional tomographic image data may be tomographic image data acquired by two-dimensional scanning with measurement light. For example, OCT data is OCT enface image data acquired from three-dimensional tomographic image data (for example, an integrated image integrated in the depth direction, an integrated value of spectral data at each XY position, a certain depth luminance data at each XY position in the vertical direction, a retinal surface layer image, etc.).

For example, the OCT angio image data may be two-dimensional OCT angio image data. Note that, for example, the two-dimensional OCT angio image data is OCT angio image data obtained by scanning the measurement light along the scanning line (transverse position) in one of the XY directions (for example, the X direction). There may be. Also, for example, the OCT angio image data may be three-dimensional OCT angio image data. Note that, for example, the three-dimensional OCT angio image data may be OCT angio image data acquired by two-dimensionally scanning measurement light. Also, for example, the OCT angio image data may be En face motion contrast data obtained from 3D motion contrast data.

For example, the ophthalmologic imaging apparatus of this embodiment includes a changing means (for example, DMD 28) that changes the profile of measurement light in the OCT optical system. For example, the changing means can change the profile of the measurement light to a plurality of mutually different first profiles (for example, the first profile 100). For example, the profile of the measurement light may be changed to at least two or more first profiles.

For example, the first profile changes the distribution of the measurement light. For example, as the distribution of the measurement light, of the measurement light irradiated toward the fundus of the eye to be inspected, the part of the eye to be inspected (for example, the pupil plane of the eye to be inspected (pupil plane ), vitreous body, etc.). Moreover, the distribution of the measurement light may be one in which the measurement light is changed into a regular pattern shape. In this case, the first profile may have a lattice pattern, striped pattern, or the like, a ring shape, or a shape obtained by enlarging or reducing the measurement light. Moreover, the distribution of the measurement light may be one in which the measurement light is changed into an irregular pattern shape. For example, the first profile may have a predetermined pattern shape in which -1 of the Walsh-Hadamard basis is an area where the eye is irradiated with the measurement light and +1 is an area where the eye is not irradiated with the measurement light, It may be a random pattern shape.

Further, for example, the ophthalmologic imaging apparatus according to the present embodiment irradiates the subject's eye with the measurement light in a state in which the profile of the measurement light is changed to a plurality of mutually different first profiles by the changing means, and obtains the respective first OCT data. An acquisition means (for example, the control unit 70) is provided. With such a configuration, the examiner tries a plurality of first profiles, and the return light of the measurement light irradiated to the eye to be examined reaches the fundus and is collected again by the OCT optical system. , it is possible to obtain information on the path along which the measurement light propagates.

For example, the changing means in this embodiment is a DMD (Digital Micromirror Device). This makes it possible to easily change the profile of the measurement light into various shapes. It should be noted that the changing means only needs to have a configuration capable of changing the profile of the measurement light. For example, in this case, in addition to the DMD, at least one of a transmissive LCD (Liquid Crystal Display), a reflective LCD, a wavefront modulation element, and the like may be used as the changing means. For example, when a DMD is used as a changing means, only discrete binary values of irradiation and non-irradiation can be taken in the profile of the measurement light, but continuous values can be taken when an LCD or wavefront modulation element is used. It is possible. Thereby, for example, the first profile can also be changed into a pattern shape such as a (discrete) cosine basis.

<Change profile of measurement light>
For example, based on the plurality of OCT data acquired by the acquiring means, the changing means changes the profile of the measurement light to a new second profile different from the first profile (for example, the second profile 200 ). The second profile has a measurement light distribution different from the measurement light distribution in the first profile. That is, the second profile is changed by the changing means into a pattern shape completely different from that of the first profile.

For example, the acquisition means acquires the second OCT data by irradiating the subject's eye with the measurement light while changing the profile of the measurement light to the second profile. At this time, the changing unit may change the profile of the measurement light to a second profile that allows more return light of the measurement light irradiated to the subject's eye to be collected (received). For example, such a second profile may be changed to a profile in which the return light of the measurement light is equal to or higher than a predetermined threshold (for example, 80%, 90%, etc.). Note that the predetermined threshold may be obtained in advance through experiments or simulations. Of course, the predetermined threshold value may be set to any value. Thereby, the examiner can refer to the first profile to change the second profile to the optimum profile for the eye to be examined, and can obtain highly accurate OCT data.

For example, the changing means changes the second profile by creating a transmittance distribution (e.g., transmittance distribution 85) of the return light of the measurement light with respect to the eye E from the plurality of OCT data acquired by the acquiring means. You may For example, the transmittance distribution may indicate the ease with which the return light of the measurement light passes through the pupil of the subject's eye. The transmittance distribution may be signal data or image data obtained by imaging the signal data. For example, as such a transmittance distribution, the ease of transmission of the return light of the measurement light may be displayed as a map.

For example, the transmittance distribution may be created based on predetermined signal intensities of the first OCT data. For example, as the signal intensity, the total amount of OCT signals may be detected. In this case, a value obtained by integrating the envelope of the OCT signal may be detected as the total amount. Further, for example, the predetermined signal intensity may be obtained by integrating absolute values in a partial wavelength region or a partial frequency region of the first OCT data. Alternatively, the predetermined signal intensity may be a feature amount such as a peak, contrast, histogram, or the like. This makes it easier to detect the difference for each first profile even when the signal saturates, for example. Alternatively, considering that the subject's eye moves, it is possible to obtain proof that the reflections are from the same location by a known segmentation process.

Note that, for example, the transmittance distribution may be created based on the luminance values in the OCT image. In this case, the rise or fall of luminance in one of the XYZ directions may be detected. Also, in this case, the luminance value may be detected for each pixel of the OCT image.

In addition, the changing means may be configured to determine strength at a predetermined signal intensity of the plurality of OCT data acquired by the acquiring means. For example, the changing means determines whether or not the detected predetermined signal strength exceeds a predetermined threshold, thereby determining whether the signal strength is strong or weak. Note that, for example, the predetermined threshold value used in the determination process may be obtained in advance through experiments or simulations.

For example, the ophthalmologic imaging apparatus according to the present embodiment, in a state where the first profile is changed to a plurality of mutually different first profiles, is one of the paths from the anterior segment to the fundus of the measurement light irradiated toward the fundus of the subject's eye. A light quantity adjusting means (for example, the control unit 70) may be provided for making the light quantity of the measuring light at the eye portion to be examined the same. For example, the ophthalmologic imaging apparatus may have a configuration in which only the first profile in which the light amount of the measurement light is the same is stored in the storage unit (for example, the memory 72). In this case, the light amount adjusting means may sequentially set the stored first profiles so that the light amount of the measurement light applied to the eye to be examined is the same. Further, for example, the ophthalmologic imaging apparatus may have a configuration in which a first profile with the same amount of measurement light and a first profile with a different amount of measurement light are mixed and stored in the storage unit. . In this case, the light amount adjusting means may select the first profiles in which the light amount of the measurement light is the same from the first profiles and set them in order.

It should be noted that, for example, when adjusting the light amount of the measurement light to be the same, the light amount adjusting means may make the sum of the light amounts of the measurement light at any part of the eye to be examined on the path from the anterior segment to the fundus equal. good. For example, the light amount adjusting means may be configured to adjust the light amount of the measuring light to be the same by controlling the changing means so that the irradiation area of the measuring light to the subject's eye becomes the same. Further, for example, the light amount adjusting means may be configured to adjust the light amount of the measurement light to be the same by controlling the output of the light source. Further, for example, the light quantity adjusting means may be configured to adjust the light quantity of the measuring light to be the same by controlling a member arranged in the optical path of the measuring light, or a member may be inserted into or removed from the optical path of the measuring light. By doing so, the light amount of the measurement light may be adjusted to be the same. For example, such a member may be a density filter, a polarizing filter, a neutral density filter, or the like. That is, the ophthalmologic imaging apparatus according to the present embodiment may have a configuration capable of matching the light amount of the measurement light irradiating the eye to be inspected in any state in which the first profile is changed. This makes it possible to easily compare the light amount of the return light of the measurement light irradiated to the subject's eye between a plurality of mutually different first profiles.

For example, the ophthalmologic imaging apparatus of this embodiment includes an illumination optical system that emits irradiation light toward the eye to illuminate the eye, and a light receiving optical system that receives the reflected light from the eye. Alternatively, an observation optical system that acquires a front image of the subject's eye based on a light receiving signal from the light receiving optical system may be provided, which is different from the OCT optical system. That is, the ophthalmologic imaging apparatus may have a configuration including a configuration of an SLO (Scanning Laser Ophthalmoscope) or a fundus camera. Of course, the configuration may be such that an SLO or a fundus camera is provided separately from the ophthalmologic imaging apparatus in this embodiment. For example, in this case, the ophthalmologic imaging apparatus may be connected to the SLO or fundus camera, and the ophthalmologic imaging apparatus may receive the front image of the subject's eye obtained by the SLO or fundus camera. In these ophthalmologic imaging apparatuses, the second changing means (for example, the control unit 70) changes the profile of the irradiation light in the illumination optical system to change the profile of the irradiation light to the same profile as the second profile. As a result, the examiner can refer to the profile of the measurement light acquired in the apparatus provided with the OCT optical system, and efficiently obtain the profile of the irradiation light in the apparatus provided with the observation optical system different from the OCT optical system. Can be the same as profile. In addition, an apparatus having an observation optical system different from the OCT optical system can accurately photograph the subject's eye.

<Example>
Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. FIG. 1 is an external configuration diagram of an ophthalmologic photographing apparatus 1 according to this embodiment. For example, the ophthalmologic imaging apparatus 1 includes a base 101 , a moving table 102 , a measuring section 103 , an operating member 104 , a face support unit 105 , a driving section 106 and a monitor 75 . For example, the movable table 102 can move in the left-right direction (X direction) and in the front-rear direction (Z direction) with respect to the base 101 . For example, the measurement unit 103 houses an optical system, which will be described later. For example, the face support unit 105 is fixed to the base 101 to support the subject's face. For example, the driving unit 106 can move in the vertical direction (Y direction) with respect to the moving table 102 . For example, the monitor 75 displays OCT data (for example, first OCT data and second OCT data), etc., which will be described later.

For example, the operation member (joystick) 104 is provided with a moving mechanism for moving the measurement unit 103 relative to the eye E to be examined. More specifically, for example, the joystick 104 has a sliding mechanism (not shown) that slides the moving table 102 on the base 101 in the XZ directions. For example, when the joystick 104 is operated, the movable table 102 slides on the base 101 in the XZ directions. Also, the joystick 104 is provided with a rotary knob. For example, when the joystick 104 is rotated, the driving section 106 drives in the Y direction, and the measuring section 103 moves in the Y direction. For example, this allows the measurement unit 103 to be moved with respect to the eye E to be examined.

In this embodiment, the configuration in which the driving unit 106 moves the measuring unit 103 in the Y direction has been described as an example, but the present invention is not limited to this. For example, the measuring section 103 may be provided with a moving mechanism that allows the measuring section 103 to move in the XYZ directions. In this case, for example, a mechanism for moving the measuring unit 103 in the XYZ directions with respect to the eye E is used to finely move the measuring unit 103, and a sliding mechanism for the moving table 102 coarsely moves the measuring unit 103. It may be used when

For example, the ophthalmologic imaging apparatus 1 in this embodiment is an optical tomography interferometer (hereinafter referred to as an OCT device 1) that acquires depth information of the eye E to be examined. For example, the OCT device 1 may be Fourier Domain Optical Coherence Tomography (FD-OCT) or Time Domain OCT (TD-OCT). Spectral domain OCT (SD-OCT: Spectral Domain OCT) and wavelength sweeping OCT (SS-OCT: Swept Source OCT) are representative of FD-OCT, and of course, the present disclosure is applied to those devices. can be

2A and 2B are schematic configuration diagrams showing the optical system and control system of the ophthalmologic imaging apparatus 1 according to this embodiment. FIG. 2A shows the optical arrangement for photographing the fundus, and FIG. 2B shows the optical arrangement for photographing the anterior segment. The OCT device 1 shown in FIGS. 2A and 2B mainly includes an interference optical system (OCT optical system) 2, a measurement optical system (light guide optical system) 20, and a controller . The OCT device 1 in this embodiment further includes a fixation target projection unit 90 (second optical system), a storage section (memory) 72 , an operation section 74 and a monitor 75 . For example, the OCT optical system 2, the measurement optical system 20, and the fixation target projection unit 90 are accommodated in the measurement unit 103 described above. Further, for example, the control unit 70 and the storage unit 72 are housed in the moving table 102 described above.

First, the OCT optical system 2 will be described. The OCT optical system 2 splits the light flux emitted from the light source 11 into measurement light and reference light. The OCT optical system 2 guides measurement light to the subject's eye E and guides reference light to the reference optical system 30 . Then, the OCT optical system 2 detects interference between the measurement light and the reference light with which the eye E to be examined is irradiated by the detector (photodetector) 40 . More specifically, in this embodiment, the detector 40 detects interference light resulting from synthesis of the measurement light reflected (or backscattered) by the subject's eye E and the reference light, and an interference signal is obtained.

For example, in the case of SD-OCT, a low coherent light source (broadband light source) is used as the light source 11, and the detector 40 is provided with a spectral optical system (spectrum meter) that disperses interference light into frequency components. For example, a spectrometer consists of a diffraction grating and a line sensor.

Further, for example, in the case of SS-OCT, a wavelength scanning light source (wavelength tunable light source) is used as the light source 11 that changes the emission wavelength at high speed, and the detector 40 includes, for example, a single light receiving element. be provided. The light source 11 is composed of, for example, a light source, a fiber ring resonator, and a wavelength selective filter. Wavelength selection filters include, for example, a combination of a diffraction grating and a polygon mirror, and a filter using a Fabry-Perot etalon.

In the OCT device 1, the optical arrangement of the measurement optical system 20 is switched. As an example, the optical arrangement shown in FIG. 2A and the optical arrangement shown in FIG. 2B may be switched. In the optical arrangements of FIGS. 2A and 2B, depth zones of regions where tomographic images are captured by the OCT device 1 are different from each other. In this embodiment, the case where SD-OCT is applied to the OCT device 1 will be described below as an example.

The OCT optical system 2 illustrated in FIGS. 2A and 2B includes a light source 11, optical fibers 15a, 15b, 15c and 15d, a splitter 15, a reference optical system 30, and a detector 40.

The light source 11 emits low coherence light used as measurement light and reference light for the OCT optical system 2 . As the light source 11, for example, an SLD light source or the like may be used. More specifically, for example, the light source 11 may emit light having a center wavelength between λ=800 nm and 1100 nm. Light from light source 11 is guided to splitter 15 via optical fiber 15a.

The optical fibers 15a, 15b, 15c, and 15d connect the splitter 15, the light source 11, the measurement optical system 20, the reference optical system 30, the detector 40, and the like by allowing light to pass through them.

Splitter 15 splits the light directed from light source 11 (via optical fiber 15a) into measurement light and reference light. The measuring light is guided to the measuring optical system 20 through the optical fiber 15b. On the other hand, the reference light is guided to the reference optical system 30 via the optical fiber 15c and the polarizer 31. FIG.

In the example of FIGS. 2A and 2B, the splitter 15 also serves as a combiner that combines the return light of the measurement light guided to the eye to be inspected E and the light guide path of the reference light (details will be described later). do). Such splitters 15 may be, for example, fiber couplers. The splitter 15 is hereinafter referred to as the coupler 15 .

For convenience, the measurement optical system 20 will now be described. The measurement optical system 20 guides measurement light to the subject's eye E, for example. As an example, the measuring optical system 20 shown in FIGS. 2A and 2B includes a collimator lens 21, a changing member 28, a mirror 29, a beam diameter adjusting section 22, a variable focusing position optical system (variable focusing position lens system) 23, a scanning It has a section (optical scanner) 24 , a mirror 25 , a dichroic mirror 26 and an objective optical system 27 .

The collimator lens 21 collimates the measurement light emitted from the end 16b of the optical fiber 15b.

The changing member 28 changes the profile of the measuring light with which the subject's eye E is irradiated by locally changing the reflected light of the measuring light incident on the changing member 28 . For example, as the changing member 28, a DMD, an LCD (for example, a reflective LCD, a transmissive LCD, etc.), a wavefront modulation element, or the like can be used. In this embodiment, a case where a DMD is used as the change member 28 will be described as an example. For this reason, the modification member 28 will be referred to as DMD 28 below.

For example, the DMD 28 has a large number of two-dimensionally arranged minute mirrors P (see FIG. 6A) that can change the angle of reflection. For example, the DMD 28 can locally change the reflection direction of the measurement light incident on the DMD 28 by controlling the reflection angle of each minute mirror P. FIG. Therefore, the profile of the measurement light irradiated to the subject's eye E is changed via the DMD 28 . In other words, the profile of the measurement light reflected by the DMD 28 is different from the profile of the measurement light incident on the DMD 28, and the eye E to be examined is irradiated with the measurement light.

The DMD 28 may change the profile of the measurement light by switching each minute mirror P between two states. In this case, the DMD 28 changes the reflection angle of the minute mirror P to ON (eg +12 degrees) or OFF (eg −12 degrees). For example, the DMD 28 may reflect the measurement light in the direction of the mirror 29 and guide the measurement light to the eye E to be examined by turning on the minute mirror P. FIG. Further, for example, the DMD 28 may reflect the measurement light in the direction of an absorption member (not shown) by turning off the minute mirror P so as not to guide the light to the eye E to be examined.

For example, DMD 28 is placed between collimator lens 21 and mirror 29 . Note that the DMD 28 is not limited to this embodiment as long as it is arranged at any position between the collimator lens 21 and the scanning unit 24 .

The beam diameter adjustment unit 22 is arranged in the optical path between the OCT optical system 2 and the scanning unit 24 (that is, the optical scanner), and is used to change the beam diameter of the measurement light in that optical path. In the examples of FIGS. 2A and 2B , the beam diameter adjustment section 22 is provided in the optical path between the coupler 15 and the scanning section 24 in the measurement optical system 20 . The beam diameter adjustment unit 22 may be, for example, at least one of an aperture that can be inserted/removed from the optical path by an insertion/removal mechanism, a variable beam expander, and a variable aperture that can adjust the diameter of the opening. For example, the beam diameter adjusting section 22 shown in FIGS. 2A and 2B in this embodiment is a variable beam expander. As shown in FIGS. 2A and 2B, the variable beam expander may include, for example, two lenses 22a and 22b and a driver 22c. The drive unit 22c changes the positional relationship between the lenses 22a and 22b in the optical axis direction based on a control signal from the control unit 70. FIG. This changes the luminous flux diameter (and numerical aperture NA) of the measurement light.

The condensing position variable optical system 23 is used to change the condensing position of the measurement light in the direction of the optical axis L1. The variable focusing position optical system 23 has at least one lens 23a, and uses the lens 23a to adjust the focusing position of the measurement light with respect to the optical axis L1 direction. In the examples of FIGS. 2A and 2B , the variable focusing position optical system 23 is provided in the optical path between the coupler 15 and the scanning section 24 . Incidentally, in this embodiment, the focusing position variable optical system 23 is arranged between the beam diameter adjusting section 22 and the scanning section 24 . However, the arrangement of the beam diameter adjusting section 22 and the focusing position variable optical system 23 is not necessarily limited to this. For example, they may be replaced with each other. Also, a relay optical system or the like may be interposed between the two. The lens 23a constitutes a focus optical system that determines the condensing position of the measurement light with respect to the direction of the optical axis L1. The variable focusing position optical system 23 may be configured with the lens 23a alone, or may be configured with the lens 23a and other optical elements. The condensing position variable optical system 23 is realized, for example, by adjusting either the refractive power of the lens 23a or the positional relationship between the objective optical system 27 and the lens 23a in the direction of the optical axis L1. The adjustment of the positional relationship between the objective optical system 27 and the lens 23a includes, for example, the position of the lens 23a with respect to the optical axis L1 direction, the optical path length between the lens 23a and the objective optical system 27a, and the lens position relative to the measurement optical path. It may be realized by either insertion or removal. In this case, the control unit 70 controls a drive unit (actuator) that moves the lens 23a in the desired direction.

In the example of FIGS. 2A and 2B, lens 23a is a variable focus lens. The lens 23a can change the focal position while it is stationary with respect to the optical axis L1. The lens 23 a changes its refractive power according to the magnitude of the applied voltage set by the control section 70 . A liquid crystal lens or the like is known as a typical variable focus lens. The lens with variable refractive power is not limited to a liquid crystal lens, and may be, for example, a liquid lens, a nonlinear optical member, a molecular member, a rotationally asymmetric optical member, or the like.

The scanning unit 24 has an optical scanner that deflects the measurement light from the OCT optical system in order to scan the measurement light. The scanning unit 24 may have, for example, two galvanomirrors 241 and 242 (an example of an optical scanner). In the example of FIG. 3, 241 is an X-scanning galvanomirror, and 242 is a Y-scanning galvanomirror. Each galvanomirror 241, 242 may include a mirror portion 241a, 242a and a drive portion 241b, 242b (for example, a motor) that rotates the respective 241a, 242a. The control unit 70 changes the traveling direction of the measurement light by independently controlling the directions of the galvano mirrors 241 and 242 . As a result, the subject's eye E can be scanned vertically and horizontally with the measurement light. Note that the scanning unit 24 can use an optical scanner other than the galvanomirrors 241b and 242b. For example, a reflective scanner (for example, a MEMS scanner, a resonant scanner, a polygon mirror, etc.) may be used, or an acoustooptic device, etc. may be used.

In the examples of FIGS. 2A and 2B, the measurement light whose traveling direction has been changed by the scanning unit 24 is reflected by the mirror 25 and the dichroic mirror 26, the mirror surfaces of which are arranged at right angles. As a result, the measurement light is folded back in the direction opposite to when it is emitted from the scanning section 24 . As a result, the measurement light is guided to the objective optical system 27 .

In this embodiment, the objective optical system 27 is fixedly arranged. More specifically, the objective optical system 27 is arranged between the scanning section 24 and the subject's eye E in the measurement optical system 20 . The objective optical system 27 guides the measurement light deflected by the optical scanner (galvanomirrors 241 and 242 in this embodiment) to the eye E to be examined. In this embodiment, the objective optical system 27 is formed as a lens system (objective lens system) having positive power. Therefore, the measurement light from the scanning unit 24 passes through the objective optical system 27 and is bent toward the optical axis L1. In FIGS. 2A and 2B, the objective optical system 27 is shown as an optical system consisting of two lenses 27a and 27b for convenience, but the number of lenses constituting the objective optical system 27 is not limited to this. . The objective optical system 27 may be replaced with one lens, or may be replaced with three or more lenses. Further, the objective optical system 27 is not limited to a lens system, and may be, for example, a mirror system, an optical system formed by combining a lens and a mirror, or an optical system other than a lens and a mirror. It may be an optical system including members.

In such a measurement optical system 20 , when measurement light is emitted from the end portion 16 b of the optical fiber 15 b , the measurement light is collimated by the collimator lens 21 . Also, the DMD 28 changes the profile of the measurement light. After that, the measuring light is reflected by the mirror 29 , passes through the beam diameter adjusting section 22 and the focusing position variable optical system 23 , and reaches the scanning section 24 . The measurement light is reflected by the two galvanomirrors provided in the scanning unit 24 and then further reflected by the mirror 25 and the dichroic mirror 26 . As a result, the measurement light enters the objective optical system 27 . Then, the measurement light passes through the objective optical system 27 and is guided to the eye E to be examined. After that, the measurement light is reflected or scattered by the subject's eye E, and as a result, traces back through the measurement optical system 20 and enters the end portion 16b of the optical fiber 15b. The measurement light incident on the end portion 16b enters the coupler 15 via the optical fiber 15b.

The OCT device 1 includes a drive section (actuator). The driving unit displaces the relative position of the scanning unit 24 (that is, the galvanometer mirrors 241 and 242, which are optical scanners) with respect to the objective optical system 27, that is, the relative position of the measuring optical system 20 in the direction of the optical axis L1. More specifically, by driving the driving section, the relative position of the scanning section 24 with respect to the back focal position of the objective optical system 27 (or its conjugate position) is changed. This displacement of the relative position changes the turning position of the measurement light with respect to the direction of the optical axis L1. The driving unit moves at least one of the scanning unit 24 and an optical member arranged between the objective optical system 27 and the scanning unit 24, thereby displacing the relative distance of the scanning unit 24 with respect to the objective optical system 27. You may let In the example of FIGS. 2A and 2B, the OCT device 1 has a driver 50. FIG. The distance (optical path length) between the objective optical system 27 and the scanning unit 24 is changed by driving the driving unit 50, thereby displacing the relative position of the scanning unit 24 with respect to the objective optical system 27. FIG. This relative position is changed according to the depth band of the subject's eye E in which the tomographic image is captured.

In the example of FIGS. 2A and 2B, the drive unit 50 integrally moves two mirrors (mirror 25 and dichroic mirror 26) whose mirror surfaces are arranged at right angles to each other in a predetermined direction. In this embodiment, it is moved in the optical axis direction of the objective optical system 27 . As a result, the optical path length from the scanning unit 24 to the objective optical system 27 is changed (for example, FIG. 2A→FIG. 2B, FIG. 2B→FIG. 2A). For example, when switching the depth band for obtaining a tomographic image between the anterior segment Ec and the fundus Er, it is necessary to change the optical path length from the scanning unit 24 to the objective optical system 27 relatively large. On the other hand, in the example of FIG. 2A, the measurement light emitted from the scanning unit 24 is reflected by the two mirrors. (in other words, the amount of displacement of the scanning unit 24 relative to the objective optical system 27 in the direction of the optical axis L1) can be doubled as the amount of movement of the two mirrors 25 and 26 . Therefore, the space required for displacing the position of the scanning unit 24 with respect to the objective optical system 27 in the direction of the optical axis L1 of the measurement optical system 20 can be suppressed.

2A and 2B, the OCT device 1 may also include a sensor 51 for detecting the position of the scanning section 24 with respect to the objective optical system 27. FIG. Various devices can be used as the sensor 51 . For example, a linear displacement sensor such as a potentiometer may be applied as sensor 51 .

Here, the explanation of the OCT optical system 2 is returned to. A reference optical system 30 generates reference light. The reference light is light combined with the reflected light of the measurement light reflected by the fundus Er. The reference optical system 30 may be of the Michelson type or of the Mach-Zehnder type. The reference optical system 30 illustrated in FIGS. 2A and 2B is formed by a reflective optical system (for example, the reference mirror 34). In the example of FIGS. 2A and 2B, the light from the coupler 15 is returned to the coupler 15 by being reflected by the reflective optical system, and as a result is guided to the detector 40 . Note that the reference optical system 30 is not necessarily limited to this, and may be formed by a transmissive optical system (for example, an optical fiber). In this case, the reference optical system 30 guides the reference light split by the coupler 15 to the detector 40 by transmitting the reference light without returning it to the coupler 15 .

2A and 2B, the reference optical system 30 has an optical fiber 15c, an end 16c of the optical fiber 15c, a collimator lens 33, and a reference mirror 34 on the optical path from the splitter 15 to the reference mirror 34. is doing. The optical fiber 15c is rotationally moved by the driver 32 to change the polarization direction of the reference light. That is, the optical fiber 15c and the driving section 32 are used as a polarizer 31 for adjusting the polarization direction. The polarizer is not limited to the above configuration, and may be any device that substantially matches the polarization states of the measurement light and the reference light by driving the polarizer arranged in the optical path of the measurement light or the optical path of the reference light. . For example, it is possible to change the polarization state by using a half-wave plate or a quarter-wave plate, or applying pressure to the optical fiber to deform it.

The polarizer 31 (polarization controller) may be configured to adjust the polarization direction of at least one of the measurement light and the reference light in order to match the polarization directions of the measurement light and the reference light. For example, the polarizer 31 may be arranged in the optical path of the measurement light.

Further, the reference mirror 34 is displaced in the optical axis direction L2 by the reference mirror drive section 34a. The optical path length of the reference light is adjusted by displacing the reference mirror 34 .

The reference light emitted from the end 16c of the optical fiber 15c is collimated by the collimator lens 33 and reflected by the reference mirror . After that, the reference light is condensed by the collimator lens 33 and enters the end portion 16c of the optical fiber 15c. The reference light incident on the end portion 16c reaches the coupler 15 via the optical fiber 15c and the optical fiber 31 (polarizer 31).

In the examples of FIGS. 2A and 2B, the reference light reflected by the reference mirror 34 and the return light of the measurement light guided to the subject's eye E (that is, the measurement light reflected or scattered by the subject's eye E) are , are combined by a coupler 15 to form interference light. This interference light is emitted from the end portion 16d via the optical fiber 15d. As a result, interfering light is directed to detector 40 .

In order to obtain an interference signal for each frequency (wavelength), the detector (here, spectrometer section) 40 splits the interference light between the reference light and the measurement light for each frequency (wavelength), and divides the split interference light. receive light.

The detector 40 shown in FIGS. 2A and 2B may include, for example, an optical system such as a collimator lens, grating mirror (diffraction grating), condenser lens, etc. (all not shown). A one-dimensional light receiving element (line sensor), for example, may be applied to the main body (light receiving element portion) of the detector 40 . Detector 40 is sensitive to the wavelength of light emitted from light source 11 . As described above, if the light source 11 emits light in the infrared region, a detector 40 sensitive to the infrared region may be used.

The interference light emitted from the end portion 16b is collimated by the collimator lens 21 and then split into frequency components by a grating mirror (not shown). Then, the interference light split into frequency components is condensed on the light receiving surface of the detector 40 via a condensing lens (not shown). Thereby, spectral information (spectral signal) of the interference fringes on the detector 40 is obtained. The spectrum information is input to the control section 70 and analyzed by the control section 70 using Fourier transform. Then, a tomographic image of the subject's eye E is formed as an analysis result. Moreover, as an analysis result, the information in the depth direction of the eye E to be examined can be measured.

Here, the controller 70 can obtain a tomographic image by scanning the eye E to be inspected E with the measurement light in the transverse direction by the scanning unit 24 . For example, by scanning in the X direction or the Y direction, a tomographic image in the XZ plane or the YZ plane of the fundus Er of the subject's eye can be obtained (in the present embodiment, the measurement light is directed to the fundus Er in this way, A method of obtaining a tomographic image by performing an original scan is referred to as a B scan). Note that the acquired tomographic image is stored in the storage unit 72 connected to the control unit 70 . Furthermore, by controlling the driving of the scanning unit 24 and scanning the measurement light two-dimensionally in the XY directions, a two-dimensional moving image of the fundus Er of the subject's eye in the XY directions and a three-dimensional image of the fundus Er of the subject's eye are produced. can be formed based on the output signal from detector 40 .

Next, the fixation target projection unit 90 will be described. The fixation target projection unit 90 has an optical system for guiding the line-of-sight direction of the eye E to be examined. The fixation target projection unit 90 has a fixation target (fixation light source 91) to be presented to the eye E to be examined. The fixation target projection unit 90 may be configured to guide the subject's eye E in a plurality of directions. Here, the dichroic mirror 26 has a characteristic of reflecting light of wavelength components used as measurement light for the OCT optical system 2 and transmitting light of wavelength components used for the fixation target projection unit 90 . Therefore, the fixation target light flux emitted from the fixation target projection unit 90 is applied to the subject's eye E via the objective optical system 27 . This allows the subject to fixate.

<Control system>
Next, the control system of the OCT device 1 will be explained. A control unit (controller) 70 controls each unit of the OCT device 1 . For example, the control unit 70 may be configured including a CPU (processor), memory, and the like. Further, in this embodiment, the control unit 70 acquires depth information of the subject's eye E by, for example, processing the output signal (that is, the interference signal) from the detector 40 . The depth information includes image information such as a tomographic image, dimension information indicating the dimensions of each part of the eye to be examined E, information indicating the amount of movement in the irradiated portion of the measurement light, an analysis signal (complex number) including polarization characteristic information, At least one of the above may be used. In this embodiment, the controller 70 also serves as an image processor that forms a tomographic image of the subject's eye E based on the interference signal. In addition, the control unit 70 of the present embodiment performs various types of image processing in addition to tomographic image formation. Image processing may be performed by a dedicated electronic circuit (for example, an image processing IC (not shown)) provided in the control unit 70, or may be performed by a processor (for example, CPU).

A storage unit 72, an operation unit (user interface) 74, and a monitor 75 are connected to the control unit 70 (see FIGS. 2A and 2B). The storage unit 72 may include a rewritable non-transitory storage medium, such as flash memory or hard disk. Images and measurement data obtained as a result of photographing and measurement are stored in the storage unit 72 . A program and fixed data defining an imaging sequence in the OCT device 1 may be stored in the storage unit 72 or may be stored in the ROM within the control unit 70 . In addition to the light source 11, the detector 40, various driving units 22c, 23a, 241a, 242b, 32, 34a and 50, a sensor 51 and the like are connected.

<Switching operation of photographing depth band>
For example, the OCT device 1 having the above configuration may switch the depth zone of the imaging region in the eye E to be examined. In this case, the control unit 70 controls the driving unit 50 to switch the turning position of the measurement light in the eye E to be examined in the direction of the optical axis L1. The turning position is displaced according to the relative position of the scanning section 24 with respect to the objective optical system 27 . That is, in this embodiment, the control unit 70 causes the driving unit 50 to change the relative position of the scanning unit 24 with respect to the objective optical system 27. As a result, the turning position of the measurement light in the subject's eye E is changed with respect to the optical axis L1 direction. adjust. At that time, the controller 70 changes the turning position of the measurement light between at least the first position and the second position. The first position corresponds to the first depth zone of the eye to be examined E (for example, the anterior segment Ec of the eye to be examined E), and the second position corresponds to the second depth zone of the eye to be examined E different from the first depth zone ( For example, it corresponds to the fundus Er) of the eye E to be examined. Also, the second position is different from the first position with respect to the optical axis direction of the measuring optical system (the depth direction of the subject's eye E).

Further, when the turning position of the measurement light in the subject's eye E is switched with respect to the direction of the optical axis L1, the control unit 70 changes the position of the reference optical system 30 in conjunction with the change in the relative position between the objective optical system 27 and the scanning unit 24. You may adjust the optical path length in . Further, the controller 70 may control the focusing position variable optical system 23 to switch the focusing position of the measurement light. Furthermore, the controller 70 may control the beam diameter adjuster 22 to adjust the NA. Such change of the position of the scanning unit 24 (in other words, change of the imaging depth range) may be performed based on a switching signal output from the operation unit 74 to the control unit 70, for example. Alternatively, the control unit 70 may automatically switch in a series of imaging sequences.

For example, when photographing the anterior segment of the subject's eye E, as shown in FIG. 2B, the control unit 70 moves the scanning unit 24 closer to the objective optical system 27 than when photographing the fundus (see FIG. 2A). At this time, the principal ray of the measurement light becomes telecentric (or substantially telecentric) on the object side (eye to be examined side) of the objective optical system 27 . That is, in this embodiment, the optical system composed of the scanning unit 24 and the objective optical system 27 is formed as an object-side telecentric optical system. In this case, it can be considered that the turning position (the first position in the present embodiment) of the measurement light in the subject's eye E is the point at infinity on the optical axis L1. Further, in this case, the principal ray of the measurement light irradiated onto the pupil plane of the subject's eye E from the front surface of the objective optical system 27 (that is, the lens surface arranged closest to the subject's eye) is reflected by the scanning unit 24. It becomes parallel (substantially parallel) to the optical axis L1 regardless of the direction of the measurement light.

On the other hand, when photographing the fundus, as shown in FIG. 2A, the control unit 70 moves the scanning unit 24 away from the objective optical system 27 as compared to when photographing the anterior segment (see FIG. 2B). At this time, as the scanning unit 24 is driven, the measurement light emitted from the front surface of the objective optical system 27 (the lens surface closest to the subject's eye) rotates around the pupil position (rotation point). That is, in this case, the turning position (the second position in the present embodiment) of the measurement light in the subject's eye E is set to the pupil position.

For the positional relationship and details of the measurement optical system 20 when photographing the anterior segment of the subject's eye E and when photographing the fundus, please refer to Japanese Patent Application Laid-Open No. 2016-209577.

<Control action>
Hereinafter, the control operation of the OCT device 1 having the above configuration will be described in order using the flowchart shown in FIG. For example, the ophthalmologic imaging apparatus 1 has an anterior segment imaging mode for imaging the anterior segment Ec of the eye E to be examined and a fundus imaging mode for imaging the fundus Er of the eye E to be examined. A case of applying the shooting mode will be taken as an example. For example, in the fundus photographing mode, measurement light is applied to the fundus through the pupil plane of the subject's eye. In this case, the pupil plane of the eye E to be examined may be irradiated with measurement light having a certain diameter.

For example, the examiner instructs the subject to gaze at the fixation target of the fixation target projection unit 90 . Alignment index images Ma to Mh, which will be described later, are projected onto the subject's eye E by turning on the light source of the index projection optical system (not shown). The anterior segment Ec of the subject's eye E is detected by an anterior segment imaging optical system (not shown), and an anterior segment observed image 60 (see FIG. 5) is displayed on the monitor 75 .

<Alignment of eye to be examined (S1)>
For example, the control unit 70 detects the alignment state between the subject's eye E and the measurement optical system 20 using the alignment index images Ma to Mh. Further, the control unit 70 controls the moving table 102 and the driving unit 106 to move the measurement unit 103, thereby adjusting the corneal vertex position (or approximately the corneal vertex position) of the eye E to be examined and the optical axis L1 of the measurement light. , and automatic alignment is performed (S1).

FIG. 5 is a diagram showing an anterior segment observed image 60 of the eye E to be examined. For example, the alignment state of the subject's eye E in the horizontal direction (X direction) and the vertical direction (Y direction) is determined using an alignment reference position preset at a position where the corneal vertex position and the optical axis L1 are aligned. . For example, the control unit 70 detects the ring-shaped XY center coordinates (the cross mark shown in FIG. 5) in the index images Ma to Mh as the corneal vertex position. In addition, the control unit 70 obtains the amount of displacement of the detected corneal vertex position of the eye to be inspected E in the XY directions with respect to the alignment reference position. For example, the control unit 70 moves the measurement unit 103 so that the amount of displacement becomes 0, and adjusts the alignment of the eye E to be examined in the X direction and the Y direction. Note that an allowable range for judging whether or not the alignment is appropriate may be set in a predetermined area in the XY directions centering on the alignment reference position, and the measurement unit 103 may be moved so as to be within this allowable range. .

For example, the alignment state of the subject's eye E in the front-rear direction (Z direction) is determined using the alignment index images Ma to Mh. For example, index images Ma and Me are at infinity, and index images Mh and Mf are at finite distance. For example, in this embodiment, when the subject's eye E is at an appropriate position with respect to the OCT device 1 (that is, when there is no positional deviation in the Z direction), the image interval a from the index image Ma at infinity to Me is , and the image interval b from the finite index image Mh to Mf are set to have a certain constant ratio. For example, when the subject's eye E is not in an appropriate position with respect to the OCT device 1 (that is, when there is a positional shift in the Z direction), the image interval a hardly changes, but the image interval b changes. For example, the control unit 70 compares the image ratio between the image interval a and the image interval b (that is, a/b), and adjusts the alignment in the Z direction so that the ratio becomes a constant (see Japanese Laid-Open Patent Publication No. 6-1994). 46999). Of course, an allowable range for judging whether or not the alignment is appropriate may be set in a predetermined area in the Z direction centering on the alignment reference position, and the measurement unit 103 may be moved so as to be within this allowable range. .

<Implementation of optimization control (S2)>
Next, the control unit 70 starts optimizing the imaging conditions (S2). For example, by performing optimization control, the fundus region desired by the examiner can be observed with high sensitivity and high resolution. For example, optimization control includes optical path length adjustment, focus adjustment, and polarization state adjustment (polarizer adjustment).

For example, in this embodiment, optimization control is performed in the order of first automatic optical path length adjustment, focus adjustment, second automatic optical path length adjustment, and polarizer adjustment. For example, the control unit 70 sets the position of the reference mirror 34 to the initial position and sets the refractive power of the lens 23a to 0D. When the initialization is completed, the control unit 70 moves the reference mirror 34 in one direction from the initial position in predetermined steps to perform the first optical path length adjustment (first automatic optical path length adjustment). When the first optical path length adjustment is completed, the control unit 70 changes the refractive power of the lens 23a so as to focus on the anterior segment of the eye E to be examined, and performs autofocus adjustment (focus adjustment). When the autofocus adjustment is completed, the control unit 70 moves the reference mirror 34 in the direction of the optical axis L2, and performs second optical path length adjustment (second automatic optical path length adjustment) for readjusting the optical path length (fine adjustment of the optical path length). )I do. When the second optical path length adjustment is completed, the controller 70 moves the polarizer 31 to a position where the interfering light can be strongly received (that is, a position where the polarization states of the measurement light and the reference light match) to adjust the polarization state of the measurement light. do.

<Changing Measurement Light to First Profile (S3)>
For example, the controller 70 changes the profile of the measurement light in the OCT optical system 2 by controlling the DMD 28 . For example, in this embodiment, the case where the profile of the measurement light is changed by switching the state of the minute mirror P in the DMD 28 (that is, the ON state and the OFF state) will be described as an example. Thereby, the profile of the measurement light is changed to the first profile 100 (S3). Note that the profile of the measurement light may be changed to at least two or more different first profiles. As the first profile 100, the measurement light irradiated toward the fundus of the eye to be inspected is any part of the eye to be inspected (for example, the pupil plane of the eye to be inspected (pupil plane ), the vitreous body, etc.) may be used as long as the distribution of the measurement light is changed.

FIG. 6 is a diagram illustrating the DMD 28. As shown in FIG. For example, in this embodiment, each of the gratings in FIG. 6 is represented as a micromirror P (P1 to P16) that the DMD 28 has. Also, for example, the shape indicated by the dotted line in FIG. 6 represents the outer diameter 80 of the measurement light before entering the DMD 28 . That is, in this embodiment, 16 minute mirrors P are arranged at the position where the measurement light enters the DMD 28 .

FIG. 7 is a diagram showing the relationship between the DMD 28 and the first profile 100. As shown in FIG. FIG. 7(a) shows a state in which the reflection angle of the minute mirror P is switched. In FIG. 7A, the minute mirrors P whose reflection angle is ON are indicated by white areas, and the minute mirrors P whose reflection angle is OFF are indicated by hatched areas. FIG. 7(b) shows a first profile 100 (first profiles 100a to 100d) of measurement light irradiated to the subject's eye E, corresponding to the DMD 28 in the state of FIG. 7(a).

For example, when all the minute mirrors P are in the ON state (B1 in FIG. 7A), the profile of the measurement light incident on the DMD 28 is changed to the first profile 100a. That is, the measurement light is reflected toward the mirror 29 by all the minute mirrors P1 to P16 and guided to the eye E to be examined. At this time, an irradiation area 110 in which the subject's eye E is irradiated with the measurement light is created in the first profile 100a. Also, for example, when all the minute mirrors P are in the OFF state (B4 in FIG. 7A), the profile of the measurement light incident on the DMD 28 is changed to the first profile 100d. In other words, the measurement light is reflected by all the minute mirrors P1 to P16 toward the absorption member (not shown) and is not guided to the eye E to be examined. At this time, a non-irradiation region 120 in which the subject's eye E is not irradiated with the measurement light is created in the first profile 100d.

For example, when some micromirrors P are ON and other micromirrors P are OFF (B2 or B3 in FIG. 7A), the profile of the measurement light incident on the DMD 28 is It is changed to the first profile 100b or the first profile 100c. At this time, only the measurement light incident toward the minute mirror P indicated by the white area (in other words, the minute mirror P whose reflection angle is ON) is guided to the eye E to be examined. The measuring light incident on the minute mirror P indicated by the shaded area (in other words, the minute mirror P whose reflection angle is OFF) is not guided to the eye E to be examined. In other words, an illuminated area 110 and a non-illuminated area 120 are created in the first profile 100b and the first profile 100c.

For example, by changing the first profile 100, the measurement light after entering the DMD 28 can have various pattern shapes (for example, regular pattern shapes, irregular pattern shapes, random pattern shapes, etc.). ). For example, the control unit 70 in this embodiment can change the first profile 100 to a plurality of mutually different ones by controlling the DMD 28 and changing the profile of the measurement light in any number of ways.

For example, in this embodiment, in a state where the profile of the measurement light is changed to a plurality of first profiles 100 different from each other, the light amount of the measurement light with which the subject's eye E is irradiated is set to be the same. For example, in this case, the control unit 70 may equalize the total sum of the light amounts of the measurement light irradiated to the subject's eye. For example, as a configuration for setting the light amount of the measurement light to be the same, the area of the irradiation region 110 in the first profile 100 is changed according to the intensity of the measurement light from the light source 11, so that the measurement light irradiated to the eye E to be examined is The amount of light may be the same. Further, for example, as a configuration for setting the light amount of the measurement light to be the same, the light amount of the measurement light irradiated to the subject's eye E may be made to be the same by changing the output of the light source 11 . Of course, by changing the area of the irradiation region 110 in the first profile 100 and the output of the light source 11, the light amount of the measurement light irradiated to the subject's eye E may be made the same. In this embodiment, it is assumed that the intensity of the measurement light from the light source 11 is uniform everywhere, and by keeping the area of the irradiation region 110 in the first profile 100 constant, the eye E to be examined is irradiated with A case in which the same amount of measurement light is set will be taken as an example.

For example, the control unit 70 controls the minute mirror P provided in the DMD 28 so that the area of the irradiation region 110 is the same in any first profile. For example, in such a case, the memory 72 stores in advance only the first profile 100 having the same area of the irradiation region 110 (that is, the same number of minute mirrors P whose reflection angles are in the ON state). good too. In such a case, the memory 72 may store in advance a mixture of the first profile 100 with the same area of the irradiation region 110 and the first profile 100 with the different area of the irradiation region 110 . For example, the control unit 70 selects the first profile 100 having the same area of the irradiation region 110 from among the first profiles 100 stored in the memory 72, and switches the state of the minute mirror P corresponding to this.

For example, in the first profile 100b and the first profile 100c in FIG. 7B, 8 out of 16 minute mirrors P are in the OFF state, and the area of the irradiation area 110 is the same. Of course, the number of minute mirrors P to be turned off is not limited to this embodiment. As a result, when the eye to be examined E is irradiated with a constant output from the light source 11, the light amount of the measurement light can be set to be the same. It should be noted that the light amount of the measurement light irradiated to the subject's eye does not necessarily have to be the same, and the first profiles 100 having different areas of the irradiation regions 110 may be selected and set. In this case, the first OCT data may be acquired in the same manner as described below by appropriately normalizing the predetermined signal intensity obtained for each first profile.

<Acquisition of first OCT data (S4)>
For example, the control unit 70 irradiates the subject's eye E with the measurement light while changing the profile of the measurement light to a plurality of mutually different first profiles 100, and acquires the first OCT data corresponding to each of the first profiles. (S4). For example, the first OCT data may be the OCT signal itself from the detector 40, tomographic image data of the eye E to be examined, motion contrast data, or polarization characteristic data. may be For example, in this embodiment, a signal of a tomographic image of the eye E to be examined is acquired as the first OCT data. In addition, in the present embodiment, for the sake of convenience, a wide-angle fundus image will be described as an example of the first OCT data, but the present invention is not limited to this. For example, the first OCT data may be a narrow-angle fundus image. For example, in this case, it becomes easier to detect a predetermined position such as the fovea centralis. Further, for example, the first OCT data may be an image (M-scan image) obtained by continuously capturing the same position without scanning at all. Of course, the first OCT data may be obtained by obtaining data a predetermined number of times and averaging them.

For example, the control unit 70 changes the profile of the measurement light to a plurality of first profiles 100 and acquires a plurality of first OCT data corresponding to each first profile 100 . That is, in this embodiment, the profile of the measurement light is changed to a plurality of first profiles different from each other as profiles for provisional photography. Further, in the present embodiment, each first OCT data is acquired in the profile for provisional imaging.

<Analysis of first OCT data (S5)>
For example, the control unit 70 detects a predetermined signal intensity in each first profile by analyzing the acquired first OCT data (S5). Note that the OCT signal may be configured to analyze the signal before the Fourier transform, or may be configured to analyze the signal after the Fourier transform. For example, in this embodiment, the total amount of OCT signals is detected as the signal intensity by analyzing the signal before Fourier transform. For example, in this case, the control unit 70 may obtain the envelope of the OCT signal and detect the integrated value as the total amount. The predetermined signal intensity may be obtained by integrating the absolute value in a partial wavelength region or a partial frequency region of the first OCT data, or may be a feature amount such as a peak, contrast, histogram, etc. good. Further, these wavelength regions or frequency regions may be regions set in advance by experiments, simulations, or the like, or may be arbitrarily set. As a result, for example, the control unit 70 uses the relationship between the predetermined signal intensity detected for each first OCT data and the set first profile 100 to obtain information on the route through which the measurement light propagated. be able to.

<Creation of transmittance distribution (S6)>
For example, the control unit 70 may create the transmittance distribution 85 using information about the route through which the measurement light propagated (S6). For example, the transmittance distribution 85 is a distribution that can specify a position on the pupil of the eye to be inspected E, where the return light of the measurement light irradiated to the eye to be inspected E is likely to pass through or is difficult to pass through. be. The transmittance distribution may be data indicating the amount of return light of the measurement light at each position on the pupil of the eye to be examined E, or data indicating the transmittance obtained from the amount of return light of the measurement light. may be Further, the transmittance distribution may be image data obtained by visualizing (for example, mapping) data such as the amount of return light of the measurement light and the transmittance. In this embodiment, as the transmittance distribution 85, the transmittance of the return light of the measurement light is obtained, and the map is shown as an example.

FIG. 8 is a diagram for explaining the transmittance distribution 85. As shown in FIG. FIG. 8(a) shows the positions of the subject's eye E on the pupil. FIG. 8(b) shows a map of the transmittance distribution 85. FIG. For example, each grid in FIG. 8A indicates positions E1 to E16 on the pupil of the eye E to be examined. In this embodiment, the positions E1 to E16 on the pupil of the subject's eye E correspond to the positions of the minute mirrors P1 to P16 of the DMD . That is, the measurement light reflected by the minute mirror P1 of the DMD 28 passes through the position E1 on the pupil of the eye E to be examined and reaches the fundus Er. Further, the return light of the measurement light that has passed through the position E1 on the pupil of the eye to be examined E is reflected by the minute mirror P1 of the DMD 28 and reaches the coupler 15 .

Here, for example, the measurement light does not necessarily reach the fundus Er of the eye E to be examined. For example, if the eyelid of the subject's eye E, turbidity, or the like occurring in the subject's eye E exists at the position where the measurement light is incident, the measurement light may be blocked by these. Further, for example, the return light of the measurement light does not necessarily reach the coupler 15 through the same position on the optical path through which the measurement light passed. The return light of the measurement light may be scattered and reflected by the shape of the fundus Er and may pass through different positions on the optical path through which the measurement light passed. In addition, the return light of the measurement light is blocked by the eyelid of the eye to be examined E or opacity generated in the eye to be examined E, or is incident on a small mirror P or the like in the OFF state, and is reflected in the direction of the coupler 15. It may or may not.

This will be explained in more detail. For example, when only the minute mirrors P1 and P3 of the DMD 28 are in the ON state, part of the measurement light incident on the DMD 28 is reflected by the minute mirror P1 toward the eye E to be examined. At this time, the return light of the measurement light scattered and reflected by the fundus Er includes the return light that enters the DMD 28, is reflected by the minute mirror P1 and reaches the coupler 15, and the return light that is reflected by the minute mirror P3 and reaches the coupler 15. There is a return light that reaches 15 and a return light that does not reach the coupler 15 because it is reflected by the minute mirrors P (that is, minute mirrors P2, P4 to P16) in the OFF state. The return light of the measurement light reflected by the minute mirror P3 toward the subject's eye E, scattered and reflected by the fundus Er, can be explained in the same manner as described above, and therefore will be omitted.

For example, the minute mirrors P1 to P16 are set to have a specific first profile, and the measuring light beams incident on the positions E1 to E16 on the pupil of the eye to be inspected E are scattered by the fundus Er of the eye to be inspected, or After being reflected, when detected again via positions E1 to E16 on the pupil of the eye E to be inspected and minute mirrors P1 to P16, a predetermined signal intensity A is given by the following formula.

Here, x in bold is a column vector representing the ON or OFF state of the minute mirrors P1 to P16 by 1 or 0, respectively. means a row vector. Therefore, for example, when P3, P4, P7, and P9 to P16 among the minute mirrors P1 to P16 provided in the DMD 28 are in the ON state, the following equations can be used.

This means that when the minute mirror P is in the ON state, the measurement light incident on the minute mirror P is reflected in the direction of the mirror 29 without loss and guided to the eye E to be examined. Conversely, if the micromirror P is in an OFF state, the measurement light incident on the micromirror P is reflected in the direction of an absorption member (not shown) and is not guided to the subject's eye E, so that the predetermined signal strength A It means that there is no contribution to (ie the contribution is 0).

In addition, the italic T indicates that the measurement light is incident on each of positions E1 to E16 on the pupil of the eye E to be examined, and is collected again via positions E1 to E16 on the pupil of the eye to be examined E and minute mirrors P1 to P16. It is called a transfer matrix, which shows how much each path contributes to. For example, the (4, 7) component of T is the pupil of the eye to be inspected E corresponding to the minute mirror P4 when the measurement light is incident from the position E7 on the pupil of the eye to be inspected E corresponding to the minute mirror P7. It represents how much the path along which the return light of the measurement light is collected from the upper position E4 contributes to the predetermined signal intensity A. FIG.

For example, the control unit 70 substitutes the predetermined signal strength A of the first OCT data and the state x of the minute mirror P into the above equation 1, and 1 We obtain a conditional expression for the elements of the two transfer matrices T. Therefore, by acquiring a plurality of different first profiles 100 one after another, each component of the transfer matrix can be obtained from a plurality of conditional expressions by simultaneous equations. It is possible to determine how much each path contributes to the time when the measurement light is incident on each of them and collected again via positions E1 to E16 on the pupil of the eye to be examined E and minute mirrors P1 to P16. In this case, the number of variations of the first profile 100 to be acquired is generally equal to the number of variables, but the number may be reduced by making certain assumptions. For example, in this case, a technique that assumes sparsity (sparse modeling) may be used. Note that sparse modeling is widely used in CT (Computed Tomography) reconstruction, and its details are described in Quant Imaging Med Surg 2013;3(3):147-161, etc., so the description is omitted. Further, for example, when a certain assumption is made, it may be assumed that there is no sudden change, and the path of the transfer matrix T that is clearly easy to pass through is confirmed by the anterior eye observation image 60. There may be an assumption that one component is greater than the other. Also, based on an OCT image of the anterior segment captured in advance by the ophthalmologic imaging apparatus 1, it is possible to set in advance which component is large and how large. Of course, specific positions such as E1 and E2, or E3 and E4 may be grouped together to reduce variables.

For example, the control unit 70 may obtain the transmittance at the position on the pupil from the transfer matrix T described above. For example, although various methods can be considered in this case, the transmittance at the position on the pupil may be obtained by decomposing the transfer matrix T as in the following formula.

In Expression 3, Max( ) is a function that selects the maximum value among the components of T, and is used for normalization. t in bold indicates the transmittance of the measurement light incident on each of the positions E1 to E16 on the pupil of the eye E to be examined as a column vector, and the operator in the center is the column vector and the row vector for each row and This is a direct product operation that generates a matrix whose elements are the values obtained by multiplying the elements of each column. Although this is not necessarily determined uniquely, it may be obtained by using a method of reducing the error (for example, a technique such as the method of least squares).

For example, if the third component of t is calculated to be 0.5, the controller 70 may determine that the transmittance at position E3 on the pupil is 50%. For example, the control unit 70 may obtain the transmittance at each position on the pupil and map it to create a transmittance distribution 85 as shown in FIG. 8B.

For the transmittance at the position on the pupil, known weights may be set for each path from design values or the like, and the transfer matrix T may be decomposed based thereon, and the transmittance is not limited to this embodiment. When assigning such weights, the transfer matrix T may be decomposed as in the following formula. It should be noted that W is a matrix representing the weight for each route.

<Change to Second Profile of Measurement Light (S7)>
For example, the control unit 70 changes the measurement light profile to a new second profile 200 different from the first profile 100 as the profile for main imaging based on the acquired plurality of first OCT data (S7). For example, in this embodiment, the profile of the measurement light is changed to the second profile 200 based on the created transmittance distribution 85 .

FIG. 9 is a diagram for explaining the second profile 200. FIG. For example, in the transmittance distribution 85, the control unit 70 may turn off the minute mirrors P corresponding to the areas where the transmittance is equal to or less than a predetermined transmittance. For example, when the transmittance distribution 85 shown in FIG. 7B is obtained, the control unit 70 selects the minute mirrors P (that is, P8, P10 to P16) corresponding to the regions exhibiting transmittance of 50% or less. It is switched to the OFF state, and the profile of the measurement light is changed to the second profile 200 shown in FIG. For example, the predetermined transmittance may be a preset transmittance (for example, 30% or less, 50% or less, etc.), or may be configured arbitrarily set by the examiner. , the configuration may be set by the control unit 70 based on the transmittance distribution 85 .

Also, at this time, the control unit 70 controls the output of the light source 11 to adjust the light amount of the measurement light. For example, in FIG. 9, 4 minute mirrors P out of 16 minute mirrors P are in an OFF state. . In this case, for example, the control unit 70 obtains the optimum amount of light for the subject's eye E from the area of the irradiation region 110 or the non-irradiation region 120 in the second profile 200 and controls the output of the light source 11 . That is, in the case of FIG. 9, the eye E to be examined can be optimally illuminated by increasing the output of the light source four times in advance.

<Acquisition of second OCT data (S8)>
For example, the control unit 70 irradiates the subject's eye E with the measurement light while changing the profile of the measurement light to the second profile 200, and acquires second OCT data corresponding to the second profile (S8). The second OCT data may be tomographic image data of the subject's eye E, motion contrast data, or polarization characteristic data. Further, for example, the second OCT data may be configured to acquire an OCT signal (that is, a signal before being imaged) or may be configured to acquire an OCT image.

As described above, for example, the ophthalmologic imaging apparatus according to the present embodiment includes the changing means for changing the profile of the measurement light, and the first OCT in a state where the profile of the measurement light is changed to a plurality of mutually different first profiles. and acquisition means for acquiring data. Further, for example, the ophthalmologic imaging apparatus of the present embodiment changes the measurement light profile to a new second profile different from the first profile as the profile for main imaging based on a plurality of OCT data, Acquire the second OCT data with the changed profile. This allows the examiner to try a plurality of the first profiles, and the return light of the measurement light irradiated to the eye to be examined reaches the fundus of the eye and is collected again by the OCT optical system. It is possible to obtain information on whether or not has been propagated. Also, the examiner can refer to the information to change the second profile to the optimum profile for the eye to be examined. Therefore, the examiner can acquire OCT data optimized for each eye to be examined.

Further, for example, the ophthalmologic imaging apparatus of the present embodiment includes a light amount adjusting means for making the light amount of the measurement light irradiated to the subject's eye the same in a state where the first profiles are changed to a plurality of mutually different ones. This makes it possible to easily compare the light amount of the return light of the measurement light irradiated to the subject's eye between a plurality of mutually different first profiles. Therefore, the examiner can easily determine a good second profile for the subject's eye from the results of the first profile.

Also, for example, the ophthalmologic imaging apparatus in this embodiment includes a DMD as a changing unit. Therefore, the profile of the measurement light can be easily changed into various shapes.

<transformation example>
In addition, in this embodiment, when selecting a plurality of first profiles 100 different from each other, a technique of sparse modeling may be applied. In this case, all first profiles 100 stored in memory 72 are prioritized and the first profiles 100 can be selectively changed. Therefore, the control unit 70 can create the transmittance distribution 85 based on a small number of first OCT data. Note that the priority of the first profile 100 may be changed as needed during the process of creating the transmittance distribution 85 .

In this embodiment, the case where the irradiation region 110 in the second profile 200 and the irradiation region 110 in the first profile 100 have different areas has been described as an example, but the present invention is not limited to this. For example, the state of the minute mirror P of the DMD 28 may be switched so that the illuminated area 110 in the second profile 200 has the same area as the illuminated area 110 in the first profile 100 . For example, in this case, based on the acquired transmittance distribution 85, the area of the irradiation region 110 is reduced by preferentially turning off the minute mirrors P corresponding to the positions where the transmittance of the measurement light is low. The first profile 100 and the second profile 200 may be the same. Further, for example, when the area where the transmittance of the measurement light is low is wide and the number of minute mirrors P corresponding to this area exceeds the number of minute mirrors P turned off in the first profile 100. , a small mirror P that is turned off is determined in consideration of the transmittance around the area where the transmittance of the measurement light is low, and the area of the irradiation area 110 is determined by the first profile 100 and the second profile 200. may be the same.

Further, in this embodiment, the configuration in which the measurement light is locally changed by switching the state of the minute mirror P of the DMD 28 has been described as an example, but the present invention is not limited to this. For example, a member for adjusting the intensity of the measurement light may be placed in the optical path of the measurement light and moved or inserted/removed. In this case, an apodization filter may be used as a member for adjusting the intensity of the measurement light, and may be moved within a plane perpendicular to the measurement light. Also, a configuration using an LCD (for example, a transmissive LCD, a reflective LCD, or the like) may be employed. For example, in this way, the subject's eye E may be irradiated with measurement light whose intensity is partially changed.

For example, when the subject's eye E is irradiated with measurement light whose intensity is partially changed, a continuous value representing the transmittance distribution is adopted for x in bold in Equation 1. FIG. Therefore, for example, when there is strong dimming only at positions corresponding to the central vicinity (E6, E7, E10, E11) of the position on the pupil of the eye to be examined E, the following formula is obtained, and the above-described implementation You can think of it in the same way as the example. As in Equation 1, after obtaining the simultaneous equations, each component of the transfer matrix may be calculated with assumptions such as sparsity. For example, the control unit 70 may create the transmittance distribution 85 based on this and set the second profile 200 .

In this embodiment, when the first profile 100 is changed, the state of the minute mirror P is switched so that the area of the irradiation region 110 is constant, and the light amount of the measurement light is made the same. Although they have been mentioned and explained, they are not limited to these. For example, in the present embodiment, the light intensity of the measurement light may be made uniform by setting the first profiles with different areas of the irradiation regions 110 and adjusting the light intensity emitted from the light source 11 . For example, in this case, the control unit 70 changes the light amount of the measurement light according to the area of the irradiation region 110 in the set first profile 100 . For example, the control unit 70 doubles the output of the light source 11 when the area of the irradiation region 110 in the first profile 100 is half the overall area in the first profile 100 . As a result, even when the first profile 100 with different areas of the irradiation regions 110 is set, the output of the light source 11 can be changed at any time to make the light amount of the measurement light irradiated to the eye to be examined the same.

Further, for example, when the light intensity of the measurement light is made the same by adjusting the light intensity emitted from the light source 11, the light intensity of the measurement light irradiated to the subject's eye E is detected between the DMD 28 and the lens 22a. A photodetector may be provided for For example, the controller 70 may control the output of the light source 11 based on the amount of measurement light detected by the photodetector. Further, for example, the control unit 70 inserts a member for adjusting the light amount of the measurement light based on the light amount of the measurement light detected by the photodetector into the optical path until the measurement light reaches the eye E to be examined. You can take it off. For example, a filter (for example, a density filter, a polarizing filter, a neutral density filter, etc.) or the like is used as a member for adjusting the amount of light. If a density-variable filter is used, it may be fixedly arranged in the optical path until the measurement light reaches the eye to be examined E, and may be rotated or slid to obtain a desired density. For example, even with such a configuration, when the first profiles 100 with different areas of the irradiation regions 110 are set, the light amount of the measurement light irradiated to the subject's eye can be made the same.

Note that the ophthalmologic imaging apparatus 1 in this embodiment may be configured to include a photodetector 88 for detecting the return light of the measurement light. FIG. 10 is a diagram showing a modified example of the optical system of the ophthalmologic imaging apparatus 1. As shown in FIG. For example, in such a case, a beam splitter 87 is provided somewhere between the DMD 28 and the lens 22a (in this embodiment, between the mirror 29 and the lens 22a), and the beam reflected by the subject's eye E is measured. The return light of the light is reflected by the beam splitter 87 toward the photodetector 88 . For example, the detector 40 may acquire an OCT signal by synthesizing the return light of the measurement light guided to the photodetector 88 and the reference light. For example, the control unit 70 can detect a predetermined signal strength A from the acquired OCT signal in the same manner as in the present embodiment.

For example, in the case of the optical system arrangement shown in FIG. 10, the transfer matrix can be similarly obtained by the following formula. Here, a bold 1 is a row vector in which all components are 1, and corresponds to the row vector when all micromirrors P of the DMD 28 are ON in Equation 1. As in Equation 1, after obtaining the simultaneous equations, each component of the transfer matrix may be calculated with assumptions such as sparsity. For example, the control unit 70 may create the transmittance distribution 85 based on this and set the second profile 200 .

Note that, for example, the ophthalmologic imaging apparatus 1 in this embodiment may have an illumination optical system, a light receiving optical system, and an observation optical system different from the OCT optical system 2 . For example, the illumination optical system illuminates the subject's eye by emitting irradiation light toward the subject's eye. For example, the light receiving optical system receives reflected light from the subject's eye. For example, the observation optical system acquires a front image of the subject's eye based on the received light signal from the light receiving optical system. Note that the ophthalmologic imaging apparatus 1 may be configured to include an SLO or a fundus camera.

For example, in the ophthalmologic imaging apparatus 1 described above, the control unit 70 changes the profile of irradiation light in the irradiation optical system. For example, the controller 70 can change the profile of the irradiation light to the same profile as the second profile. In this case, the DMD 28 may be arranged in the optical path common to the illumination optical system and the measurement optical system 20. FIG. Also, in this case, the pattern of the second profile may be arranged on the aperture plane of the SLO or fundus camera. For example, with such a configuration, the profile of the illumination light in the illumination optical system is changed to the same profile as the second profile of the measurement light.

For example, as described above, the ophthalmologic imaging apparatus in this embodiment includes an illumination optical system that emits irradiation light toward the eye to illuminate the eye, a light receiving optical system that receives the reflected light from the eye, An observation optical system different from the OCT optical system that acquires a front image of the subject's eye based on a light receiving signal from the light receiving optical system, and a second changing means that changes the profile of the illumination light in the illumination optical system. For this reason, the examiner refers to the profile of the measurement light obtained in the apparatus provided with the OCT optical system, and efficiently obtains the profile of the irradiation light in the apparatus provided with the observation optical system different from the OCT optical system. Can be the same as profile. In addition, an apparatus having an observation optical system different from the OCT optical system can accurately photograph the subject's eye.

In this embodiment, the configuration in which the transmittance distribution 85 for the subject's eye E is created using the predetermined signal intensity A obtained by analyzing all the first OCT data has been described as an example, but the present invention is not limited to this. For example, the transmittance distribution 85 may be created based on the strength of a predetermined signal strength A determined by the first OCT data. In this case, the transmittance distribution 85 may be created using only a plurality of first OCT data judged to be "strong" or created using only a plurality of first OCT data judged to be "weak". good. For example, the magnitude of the predetermined signal strength A based on the first OCT data can be determined by comparing the obtained amplitude strength with a predetermined threshold set in advance by experiments, simulations, or the like. Of course, such a threshold may be arbitrarily set by the examiner, or may be set each time the examinee changes (each eye E to be examined changes).

In this embodiment, the case where an OCT signal is analyzed as the first OCT data and a predetermined signal strength A is detected has been described as an example, but the present invention is not limited to this. For example, an OCT signal may be analyzed as the first OCT data, and the peak of the signal value, the contrast, and the feature amount such as a histogram may be detected. In this case, for example, it may be obtained by detecting the rise or fall of the first OCT data, or may be obtained by cutting out a part of the first OCT data. Of course, an OCT image may be analyzed as the first OCT data to detect the luminance value.

In addition, in the present embodiment, by using the created transmittance distribution 85, the position of turbidity or the like occurring in the eye E to be examined may be estimated. In this case, for example, the control unit 70 may estimate a position on the pupil of the subject's eye E where the return light of the measurement light is less likely to pass through as a position of turbidity or the like.

1 ophthalmic photographing apparatus 11 light source 15 splitter 20 measuring optical system 22 beam diameter adjusting section 23 variable focusing position optical system 24 scanning section 27 objective optical system 28 changing member 30 reference optical system 40 detector 50 driving section 70 control section 100 th 1 profile 103 measuring unit 200 second profile

Claims (3)

An ophthalmic imaging apparatus having an OCT optical system for detecting OCT signals from measurement light and reference light irradiated to the fundus of a subject's eye, and acquiring OCT data of the subject's eye by processing the OCT signals,
A profile showing the distribution of the measurement light in the OCT optical system, which is a profile showing the distribution of the measurement light in the path from the anterior segment to the fundus of the measurement light irradiated toward the fundus of the eye to be examined. a means for changing;
In a state in which the distribution of the measurement light in the path from the anterior segment to the fundus is changed to a plurality of first profiles for provisional imaging, which are different from each other, by the change means, the irradiation position set on the fundus of the eye to be examined. acquisition means for irradiating the measurement light and acquiring first OCT data for each of the plurality of first profiles;
with
The changing means acquires a transmittance distribution of return light with respect to the fundus of the subject's eye from the plurality of first OCT data acquired by the acquiring means, and based on the transmittance distribution, sets a profile for main imaging as a front changing the distribution of the measurement light in the path from the eye to the fundus to a new second profile different from the first profile;
The acquisition means acquires the second OCT data by irradiating the irradiation position of the fundus of the subject eye with the measurement light in a state where the profile has been changed to the second profile. The ophthalmic imaging apparatus of claim 1,
in the path from the anterior segment to the fundus the subject eye in a state where the distribution of the measurement light is changed to a plurality of the first profiles different from each other;fundusan ophthalmologic imaging apparatus, comprising a light amount adjusting means for adjusting the light amount of the measuring light irradiated to the same. An ophthalmologic imaging method having an OCT optical system for detecting OCT signals from measurement light and reference light irradiated to the fundus of an eye to be examined, and acquiring OCT data of the eye to be examined by processing the OCT signals,
A profile showing the distribution of the measurement light in the OCT optical system, which is a profile showing the distribution of the measurement light in the path from the anterior segment to the fundus of the measurement light irradiated toward the fundus of the eye to be examined. In a state in which the distribution of the measurement light in the path from the anterior segment to the fundus is changed to a plurality of first profiles for provisional imaging by the changing means, the irradiation position set on the eye to be inspected is changed. a first acquisition step of irradiating the measurement light and acquiring first OCT data of each of the plurality of first profiles;
A transmittance distribution of return light to the fundus of the subject eye is acquired from the plurality of first OCT data acquired in the first acquisition step, and based on the transmittance distribution, a profile for main imaging is obtained from the anterior segment of the eye. a changing step of changing the distribution of the measurement light on the path to the fundus to a new second profile different from the first profile;
a second acquiring step of acquiring second OCT data by irradiating the measurement light onto the irradiation position of the fundus of the subject eye in the state changed to the second profile by the changing step;
An ophthalmologic imaging method comprising:

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