JP2022029174A

JP2022029174A - Fundus imaging apparatus

Info

Publication number: JP2022029174A
Application number: JP2020132378A
Authority: JP
Inventors: 真也岩田; Shinya Iwata; 潤平西山; Junpei Nishiyama
Original assignee: Nidek Co Ltd
Current assignee: Nidek Co Ltd
Priority date: 2020-08-04
Filing date: 2020-08-04
Publication date: 2022-02-17

Abstract

To satisfactorily image a fundus by stabilizing the fixation of a subject eye.SOLUTION: A fundus imaging apparatus comprises; an OCT optical system for acquiring OCT data based on measurement light applied on the fundus of a subject eye and reference light; and a front face imaging optical system for taking a fundus front face image by scanning light on the fundus of the subject eye. Light scanned on the fundus of the subject eye by the front face imaging optical system has a waveform longer than λ=850nm which is a waveform region where the subject eye has difficulty in viewing the scanned light.SELECTED DRAWING: Figure 1

Description

本開示は、被検眼の眼底を撮影する眼底撮影装置に関する。 The present disclosure relates to a fundus photography apparatus that photographs the fundus of an eye to be inspected.

眼底撮影装置としては、眼底の断層画像を撮影するＯＣＴ装置の他、被検眼の眼底の正面画像を撮影する装置が知られている。被検眼眼底の正面画像を撮影する眼底撮影装置としては、眼底カメラが一般的であるが、近年では、眼底上で光を走査する走査型眼底撮影装置が臨床現場でも使用されつつある。走査型眼底撮影装置は、可視光を走査してカラーの眼底正面像を撮影する単体の装置として用いられる場合の他、ＯＣＴや視野計等の眼底観察系として用いられる場合もある（例えば、特許文献１参照）。 As a fundus imaging device, in addition to an OCT device that captures a tomographic image of the fundus, a device that captures a frontal image of the fundus of the eye to be inspected is known. A fundus camera is generally used as a fundus camera for capturing a frontal image of the fundus to be inspected, but in recent years, a scanning fundus camera that scans light on the fundus is being used in clinical practice. The scanning fundus photography device may be used as a single device that scans visible light to capture a color frontal image of the fundus, or may be used as a fundus observation system such as an OCT or a perimeter (for example, a patent). See Document 1).

なお、従前の走査型眼底撮影装置においては、可視光に比較的近い波長特性の光（例えば、λ＝７８０ｎｍ）が眼底観察用として用いられている。 In the conventional scanning fundus photography apparatus, light having a wavelength characteristic relatively close to visible light (for example, λ = 780 nm) is used for fundus observation.

特開２０１６－１０４１０５号公報Japanese Unexamined Patent Publication No. 2016-104105

ところで、人眼の視感度は、８５０ｎｍぐらいまで感度を持つと言われている。そこで、ＯＣＴ装置においては、ＯＣＴデータの取得時の被検眼の追従を避けるため、λ＝１０００ｎｍ～１１００ｎｍの間に中心波長を持つＳＳ－ＯＣＴが知られている。 By the way, the visual sensitivity of the human eye is said to have a sensitivity of up to about 850 nm. Therefore, in the OCT apparatus, SS-OCT having a center wavelength between λ = 1000 nm and 1100 nm is known in order to avoid tracking of the eye to be inspected when acquiring OCT data.

しかしながら、上記のＳＳ－ＯＣＴにおいても、眼底観察用の光に関しては、可視光に比較的近い波長特性の光が用いられているのが現状である。本発明者等は、眼底観察光による走査光を被検眼が追従することによって、固視が安定せず、ＯＣＴデータの取得、カラーの眼底正面像の撮影等に悪影響を及ぼすことを見出した。 However, even in the above SS-OCT, as for the light for observing the fundus, the light having a wavelength characteristic relatively close to that of visible light is currently used. The present inventors have found that the eye to be inspected follows the scanning light from the fundus observation light, so that the fixation is not stable, which adversely affects the acquisition of OCT data, the acquisition of a color frontal image of the fundus, and the like.

本開示は、上記問題点を鑑み、被検眼の固視を安定させ、眼底を好適に撮影できる眼底撮影装置を提供することを技術課題とする。 In view of the above problems, it is a technical subject of the present disclosure to provide a fundus photography apparatus capable of stabilizing the fixation of the eye to be inspected and appropriately photographing the fundus.

上記課題を解決するために、本発明は以下のような構成を備えることを特徴とする。 In order to solve the above problems, the present invention is characterized by having the following configurations.

（１）
被検眼眼底に照射された測定光と参照光によるＯＣＴデータを取得するためのＯＣＴ光学系と、被検眼眼底上で光を走査することにより眼底正面画像を撮像するための正面撮像光学系と、を備える眼底撮影装置において、
前記正面撮像光学系によって被検眼眼底上で走査される走査光は、被検眼にとって走査光を視認しづらい波長領域であるλ＝８５０ｎｍよりも長波長であることを特徴とする。
（２）
可視光により被検眼眼底に刺激点を投影して視野測定を行うための測定光学系と、被検眼眼底上で光を走査することにより眼底正面画像を撮像するための正面撮像光学系と、を備える眼底撮影装置において、
前記正面撮像光学系によって被検眼眼底上で走査される走査光は、被検眼にとって走査光を視認しづらい波長領域であるλ＝８５０ｎｍよりも長波長であることを特徴とする。
（３）
可視光により被検眼眼底を撮影するための可視撮影光学系と、被検眼眼底上で光を走査することにより眼底正面画像を撮像するための正面撮像光学系と、を備える眼底撮影装置において、
前記正面撮像光学系によって被検眼眼底上で走査される走査光は、被検眼にとって走査光を視認しづらい波長領域であるλ＝８５０ｎｍよりも長波長であることを特徴とする。 (1)
An OCT optical system for acquiring OCT data from the measurement light and reference light applied to the fundus of the eye to be inspected, and a frontal image pickup optical system for capturing a frontal image of the fundus by scanning the light on the fundus of the eye to be inspected. In a fundus photography device equipped with
The scanning light scanned on the fundus of the eye to be inspected by the frontal imaging optical system is characterized by having a wavelength longer than λ = 850 nm, which is a wavelength region in which it is difficult for the eye to be inspected to visually recognize the scanned light.
(2)
A measurement optical system for projecting a stimulus point on the fundus of the eye to be inspected with visible light to measure the field of view, and a frontal imaging optical system for capturing a frontal image of the fundus by scanning light on the fundus of the eye to be inspected. In the fundus photography device provided
The scanning light scanned on the fundus of the eye to be inspected by the frontal imaging optical system is characterized by having a wavelength longer than λ = 850 nm, which is a wavelength region in which it is difficult for the eye to be inspected to visually recognize the scanned light.
(3)
In a fundus photography apparatus including a visible photographing optical system for photographing the fundus of the eye to be inspected with visible light and a frontal imaging optical system for capturing an image of the front of the fundus by scanning light on the fundus of the eye to be inspected.
The scanning light scanned on the fundus of the eye to be inspected by the frontal imaging optical system is characterized by having a wavelength longer than λ = 850 nm, which is a wavelength region in which it is difficult for the eye to be inspected to visually recognize the scanned light.

本開示によれば、被検眼の固視を安定させ、眼底を好適に撮影できる。 According to the present disclosure, it is possible to stabilize the fixation of the eye to be inspected and to appropriately image the fundus.

以下、本実施形態に係る眼底撮影装置について説明する。眼底撮影装置は、ＯＣＴ光学系と、正面撮像光学系と、を備えてもよい。 Hereinafter, the fundus photography apparatus according to this embodiment will be described. The fundus photography apparatus may include an OCT optical system and a frontal imaging optical system.

＜ＯＣＴ光学系＞
ＯＣＴ光学系は、例えば、被検眼眼底に照射された測定光と参照光によるＯＣＴデータを取得するためのＯＣＴ光学系であってもよく、さらに、測定光を被検眼眼底上で走査させるための走査部を備えてもよい。 <OCT optical system>
The OCT optical system may be, for example, an OCT optical system for acquiring OCT data of the measurement light and the reference light applied to the fundus of the eye to be inspected, and further, for scanning the measurement light on the fundus of the eye to be inspected. It may be provided with a scanning unit.

＜正面撮像光学系＞
正面撮像光学系は、例えば、被検眼眼底上で光を走査することにより眼底正面画像を撮像するための正面撮像光学系であってもよく、さらに、光を眼底上で走査させるための走査部（光スキャナ）備えてもよい。 <Front image pickup optical system>
The frontal imaging optical system may be, for example, a frontal imaging optical system for capturing a frontal image of the fundus by scanning light on the fundus of the eye to be inspected, and further, a scanning unit for scanning light on the fundus. (Optical scanner) may be provided.

正面撮像光学系としては、例えば、眼底上でスポット光を二次元的に走査する構成であってもよいし、スリット光を一次元的に走査する構成であってもよい。また、走査部としては、例えば、走査ミラー（例えば、ガルバノミラー、レゾナントスキャナ）であってもよいし、スリットが形成されたチョッパーを回転駆動させる構成であってもよい。 The front image pickup optical system may be configured to scan the spot light two-dimensionally on the fundus of the eye, or may scan the slit light one-dimensionally, for example. Further, the scanning unit may be, for example, a scanning mirror (for example, a galvano mirror or a resonant scanner), or may be configured to rotationally drive a chopper having a slit formed therein.

正面撮像光学系は、例えば、走査型レーザ検眼鏡（ＳＬＯ：Scanning Laser Ophthalmoscope）に基づくＳＬＯ光学系であってもよく、ポイントセンサ又はラインセンサが受光素子として用いられてもよい。正面撮像光学系は、スリットスキャンタイプの眼底カメラであってもよく、二次元撮像素子が受光素子として用いられてもよい。 The frontal imaging optical system may be, for example, an SLO optical system based on a scanning laser ophthalmoscope (SLO), and a point sensor or a line sensor may be used as a light receiving element. The front image pickup optical system may be a slit scan type fundus camera, or a two-dimensional image pickup element may be used as a light receiving element.

正面撮像光学系によって眼底上で走査される走査光は、被検眼にとって走査光を視認しづらい波長領域であるλ＝８５０ｎｍよりも長波長であってもよい。これにより、例えば、正面撮像光学系２００の光走査を被検眼が追従しづらくなる。結果として、被検眼の固視が安定した状態でのＯＣＴデータを取得できるので、良好なＯＣＴデータを取得できる。 The scanning light scanned on the fundus by the frontal imaging optical system may have a wavelength longer than λ = 850 nm, which is a wavelength region in which it is difficult for the eye to be inspected to see the scanned light. This makes it difficult for the eye to be inspected to follow the optical scan of the front image pickup optical system 200, for example. As a result, it is possible to acquire OCT data in a state where the fixation of the eye to be inspected is stable, so that good OCT data can be acquired.

より好ましくは、正面撮像光学系によって被検眼眼底上で走査される走査光は、被検眼にとって不可視領域であるλ＝９００ｎｍよりも長波長であってもよい。これによって、例えば、正面撮像系の光走査を被検眼が追従してしまうことを防止できるので、良好なＯＣＴデータを取得することができる。結果として、被検眼の固視がより安定した状態でのＯＣＴデータを取得できるので、より良好なＯＣＴデータを取得できる。 More preferably, the scanning light scanned on the fundus of the eye to be inspected by the frontal imaging optical system may have a wavelength longer than λ = 900 nm, which is an invisible region for the eye to be inspected. As a result, for example, it is possible to prevent the eye to be inspected from following the optical scan of the front image pickup system, so that good OCT data can be acquired. As a result, it is possible to acquire OCT data in a state where the fixation of the eye to be inspected is more stable, so that better OCT data can be acquired.

例えば、走査光は、ＯＣＴ光学系によるＯＣＴデータの取得中に並行して、眼底上で照射されてもよい。これによって、例えば、ＯＣＴデータの取得中に、正面撮像光学系の光走査による被検眼の追従を回避でき、良好なＯＣＴデータを取得できる。また、走査光は、ＯＣＴ光学系によるＯＣＴデータの取得以外のタイミングにおいて、眼底上で照射されてもよい。これによって、例えば、正面撮像光学系による被検眼の追従を回避でき、被検眼の固視が安定した状態でＯＣＴデータの取得を開始できる。 For example, the scanning light may be emitted on the fundus in parallel during the acquisition of OCT data by the OCT optical system. Thereby, for example, it is possible to avoid tracking of the eye to be inspected by optical scanning of the front image pickup optical system during acquisition of OCT data, and good OCT data can be acquired. Further, the scanning light may be irradiated on the fundus at a timing other than the acquisition of OCT data by the OCT optical system. Thereby, for example, it is possible to avoid the tracking of the eye to be inspected by the frontal imaging optical system, and it is possible to start the acquisition of OCT data in a state where the fixation of the eye to be inspected is stable.

上記において、走査光を視認しづらい波長領域（好ましくは不可視領域）とする場合、正面撮像光学系に用いられる光源として、λ＝８５０ｎｍ（好ましくは、λ＝９００ｎｍ）よりも長い波長帯域に中心波長を持つ光を出射する光源が用いられてもよい。これによって、走査光により正面画像を得る際、波長効率が高い中心波長を活用できるので、走査光を被検眼が追従する可能性を低減しつつ、効率的なイメージングが可能となる。この場合、さらに、光源からの出射光の波長帯域の下限が、８５０ｎｍよりも長い波長であってもよいし、８５０ｎｍよりも短波長の光が光路中でカットされてもよい。これによって、中心波長以外の光によって走査光を追従してしまう可能性も低減できる。なお、正面撮像光学系の光源の波長帯域は、例えば、半値幅に基づいて規定できる。 In the above, when the scanning light is in a wavelength region (preferably invisible region) where it is difficult to see, the center wavelength is in a wavelength band longer than λ = 850 nm (preferably λ = 900 nm) as a light source used in the front imaging optical system. A light source that emits light having a wavelength may be used. As a result, when the front image is obtained by the scanning light, the central wavelength having high wavelength efficiency can be utilized, so that efficient imaging becomes possible while reducing the possibility that the eye to be inspected follows the scanning light. In this case, the lower limit of the wavelength band of the light emitted from the light source may be a wavelength longer than 850 nm, or light having a wavelength shorter than 850 nm may be cut in the optical path. This also reduces the possibility that the scanning light will be followed by light other than the center wavelength. The wavelength band of the light source of the front image pickup optical system can be defined, for example, based on the half width.

走査光を視認しづらい波長領域（好ましくは不可視領域）とする構成としては、上記構成に限定されず、例えば、中心波長がλ＝８５０ｎｍ（好ましくは、λ＝９００ｎｍ）よりも短波長であって、出射波長の上限としてλ＝８５０ｎｍよりも長波長の波長領域を含む光を出射する光源が用いられ、λ＝８５０ｎｍよりも短波長の光が、カットフィルタ等によって光路中でカットされることで、λ＝８５０ｎｍよりも長波長の光が眼底に走査される構成であってもよい。 The configuration in which the scanning light is hard to see (preferably invisible region) is not limited to the above configuration, and for example, the center wavelength is shorter than λ = 850 nm (preferably λ = 900 nm). As the upper limit of the emission wavelength, a light source that emits light having a wavelength region longer than λ = 850 nm is used, and light having a wavelength shorter than λ = 850 nm is cut in the optical path by a cut filter or the like. , Λ = Light having a wavelength longer than 850 nm may be scanned on the fundus.

上記のようなＯＣＴ光学系と正面撮像光学系を備える眼底撮影装置において、さらに、ＯＣＴ光学系に用いられる光源は、λ＝１０００ｎｍ～１１００ｎｍの間に中心波長を持つ測定光を出射する光源であってもよい。これにより、例えば、眼底上での走査光が上記波長特性であることに加え、眼底に照射される測定光が不可視領域であるので、ＯＣＴデータを得る際の被検眼の追従をより適切に回避することができる。 In the fundus photography apparatus provided with the OCT optical system and the frontal imaging optical system as described above, the light source used for the OCT optical system is a light source that emits measurement light having a center wavelength between λ = 1000 nm and 1100 nm. You may. As a result, for example, in addition to the above-mentioned wavelength characteristics of the scanning light on the fundus, the measurement light applied to the fundus is in the invisible region, so that the tracking of the eye to be inspected when obtaining OCT data is more appropriately avoided. can do.

＜実施例＞
以下、本実施形態に係る実施例について図面に基づいて説明する。 <Example>
Hereinafter, examples according to this embodiment will be described with reference to the drawings.

図１、図２は、それぞれ本実施例に係る光学系を示す図である。本実施例に係る眼底撮影装置は、対物レンズ２５と、ＯＣＴ光学系１００と、正面撮像光学系２００と、を主に備える。なお、眼底撮影装置は、さらに、被検眼を固視させるための固視標を呈示する固視光学系を備える構成であってもよい。固視光学系は、正面撮像光学系２００の一部として設けられてもよいし、別途設けられてもよい。 1 and 2 are diagrams showing an optical system according to this embodiment, respectively. The fundus photography apparatus according to this embodiment mainly includes an objective lens 25, an OCT optical system 100, and a frontal imaging optical system 200. The fundus photography device may further include a fixation optical system that presents a fixation target for fixing the eye to be inspected. The optometry optical system may be provided as a part of the frontal imaging optical system 200, or may be provided separately.

対物レンズ２５は、例えば、被検眼の眼前に配置されてもよく、一枚又は複数枚のレンズによって構成されてもよい。この場合、対物レンズ２５は、ＯＣＴ光学系１００と正面撮像光学系２００との間で共用されてもよい。 The objective lens 25 may be arranged in front of the eye to be inspected, for example, or may be composed of one or a plurality of lenses. In this case, the objective lens 25 may be shared between the OCT optical system 100 and the frontal imaging optical system 200.

＜ＯＣＴ光学系＞
ＯＣＴ光学系１００は、例えば、対物レンズ２５を介して被検眼眼底のＯＣＴデータを光干渉の技術を用いて取得するために設けられてもよい。 <OCT optical system>
The OCT optical system 100 may be provided, for example, to acquire the OCT data of the fundus of the eye to be inspected through the objective lens 25 by using the technique of optical interference.

より詳細には、ＯＣＴ光学系１００は、光源１０２と、検出器１２０と、走査部１０８と、を主に備える。光源１０２から出射された光は、分割器によって測定光と参照光に分割される。測定光は、測定光路を通って眼底Ｅｆに導かれた後、測定光路を介して検出器１２０に導かれる。参照光は、参照光路を通って検出器１２０に導かれる。検出器１２０は、被検眼眼底に照射された測定光と、参照光との干渉状態を検出する。 More specifically, the OCT optical system 100 mainly includes a light source 102, a detector 120, and a scanning unit 108. The light emitted from the light source 102 is divided into measurement light and reference light by a divider. The measurement light is guided to the fundus Ef through the measurement optical path, and then guided to the detector 120 via the measurement optical path. The reference light is guided to the detector 120 through the reference optical path. The detector 120 detects an interference state between the measurement light applied to the fundus of the eye to be inspected and the reference light.

ＯＣＴ光学系は、例えば、Spectral-domain OCT（ＳＤ－ＯＣＴ）、Swept-source OCT（ＳＳ－ＯＣＴ）などのフーリエドメインＯＣＴであってもよいし、Time-domain OCT（ＴＤ－ＯＣＴ）であってもよい。 The OCT optical system may be, for example, a Fourier domain OCT such as Spectral-domain OCT (SD-OCT) or Swept-source OCT (SS-OCT), or a Time-domain OCT (TD-OCT). May be good.

走査部（光スキャナ）１０８は、測定光路に配置され、測定光を被検眼眼底上で走査する。走査部１０８は、測定光を被検眼Ｅ上で繰り返し走査してもよい。 The scanning unit (optical scanner) 108 is arranged in the measurement optical path and scans the measurement light on the fundus of the eye to be inspected. The scanning unit 108 may repeatedly scan the measurement light on the eye E to be inspected.

眼底撮影装置は、走査部１０８の各走査位置での検出器１２０からの検出信号に基づいてＯＣＴデータを得ることができる。 The fundus photography apparatus can obtain OCT data based on the detection signal from the detector 120 at each scanning position of the scanning unit 108.

本実施例において、ＯＣＴ光学系１００の光源１０２（測定光源）としては、λ＝１０００ｎｍ～１１００ｎｍの間に中心波長を持つ光を出射する光源が用いられてもよい。この場合、例えば、光源１０２は、波長掃引光源（ＳＳ－ＯＣＴ光源）であってもよい。なお、中心波長に対するバンド幅としては、中心波長に対して±３０～６０ｎｍの波長帯域を持つ光源が用いられてもよく、例えば、光源１０２から発せられる光の波長帯域の下限は、λ＝１０００ｎｍよりも短くてもよい。 In this embodiment, as the light source 102 (measurement light source) of the OCT optical system 100, a light source that emits light having a central wavelength between λ = 1000 nm and 1100 nm may be used. In this case, for example, the light source 102 may be a wavelength sweep light source (SS-OCT light source). As the bandwidth with respect to the center wavelength, a light source having a wavelength band of ± 30 to 60 nm with respect to the center wavelength may be used. For example, the lower limit of the wavelength band of the light emitted from the light source 102 is λ = 1000 nm. May be shorter than.

この場合、ＯＣＴ光学系１００によって眼底上で走査される光は、被検眼にとって不可視領域となる、ＯＣＴ光学系１００の光走査を被検眼が追従しづらくなる。したがって、被検眼の固視を安定した状態でのＯＣＴデータを取得できるので、結果として、良好なＯＣＴデータを取得できる。 In this case, the light scanned on the fundus by the OCT optical system 100 makes it difficult for the subject to follow the optical scan of the OCT optical system 100, which is an invisible region for the eye to be inspected. Therefore, it is possible to acquire OCT data in a state where the fixation of the eye to be inspected is stable, and as a result, good OCT data can be acquired.

＜正面撮像光学系＞
正面撮像光学系２００は、例えば、対物レンズ２５を介して被検眼眼底の正面画像を得るために設けられてもよい。この場合、正面撮像光学系２００は、被検眼眼底上で光を走査することにより眼底正面画像を撮像する走査型撮像光学系（例えば、ＳＬＯ光学系）であってもよい。 <Front image pickup optical system>
The frontal imaging optical system 200 may be provided, for example, to obtain a frontal image of the fundus of the eye to be inspected via the objective lens 25. In this case, the frontal imaging optical system 200 may be a scanning type imaging optical system (for example, an SLO optical system) that captures an image of the front of the fundus by scanning light on the fundus of the eye to be inspected.

正面撮像光学系２００は、光源（例えば、レーザ光源）２０２と、受光素子２２０と、走査部２０８と、を主に備える。この場合、正面撮像光学系２００は、光源２０２からの光を眼底に投光し、光源２０２からの光による眼底反射光を受光素子２２０により受光する。 The front image pickup optical system 200 mainly includes a light source (for example, a laser light source) 202, a light receiving element 220, and a scanning unit 208. In this case, the front image pickup optical system 200 projects the light from the light source 202 onto the fundus, and receives the light reflected from the fundus by the light from the light source 202 by the light receiving element 220.

走査部２０８は、正面撮像光学系２００の光路中（例えば、瞳孔共役位置）に配置され、光源２０２からの光を眼底上で二次元的に走査するために用いられる。走査部２０８は、例えば、２つの光スキャナの組合せからなり、一方の光スキャナによって主走査方向での光走査が行われ、他方の光スキャナによって副走査方向での光走査が行われる。 The scanning unit 208 is arranged in the optical path of the front image pickup optical system 200 (for example, the pupil conjugate position), and is used to scan the light from the light source 202 two-dimensionally on the fundus. The scanning unit 208 is composed of, for example, a combination of two optical scanners, one optical scanner performs optical scanning in the main scanning direction, and the other optical scanner performs optical scanning in the sub-scanning direction.

眼底撮影装置は、走査部２０８の各走査位置での受光素子２２０からの検出信号に基づいて眼底正面画像を得ることができる。 The fundus photography apparatus can obtain a fundus front image based on the detection signal from the light receiving element 220 at each scanning position of the scanning unit 208.

正面撮像光学系２００は、例えば、被検眼の眼底を正面方向から観察するための眼底観察光学系として用いられてもよい。検者は、眼底正面画像を見ながら、眼底上のＯＣＴデータの取得位置を設定できる。また、眼底正面画像に基づいて眼底の位置ずれを検出し、検出結果に基づいてＯＣＴ光学系１００を制御することにより、眼底上のＯＣＴデータの取得位置を補正するようにしてもよい（いわゆるトラッキング）。 The frontal imaging optical system 200 may be used, for example, as a fundus observation optical system for observing the fundus of the eye to be inspected from the front direction. The examiner can set the acquisition position of the OCT data on the fundus while looking at the front image of the fundus. Further, the position deviation of the fundus may be detected based on the front image of the fundus, and the OCT optical system 100 may be controlled based on the detection result to correct the acquisition position of the OCT data on the fundus (so-called tracking). ).

本実施例において、正面撮像光学系２００の光源２０２としては、λ＝８５０ｎｍよりも長く、ＯＣＴ光学系１００の測定光（例えば、λ＝９９０ｎｍ～１１００ｎｍ）よりも短い波長帯域に中心波長を持つ光を出射する光源が用いられてもよい。なお、中心波長に対するバンド幅としては、レーザー特性を持つように、中心波長に対して±１０ｎｍの波長帯域を持つ光源が用いられてもよい。もちろん、さらに広帯域の光源が用いられてもよい。 In this embodiment, the light source 202 of the front image pickup optical system 200 is light having a center wavelength in a wavelength band longer than λ = 850 nm and shorter than the measurement light of the OCT optical system 100 (for example, λ = 990 nm to 1100 nm). A light source that emits light may be used. As the bandwidth with respect to the center wavelength, a light source having a wavelength band of ± 10 nm with respect to the center wavelength may be used so as to have laser characteristics. Of course, a light source having a wider band may be used.

この場合、正面撮像光学系２００によって眼底上で走査される走査光は、被検眼にとって走査光を視認しづらい波長領域であるλ＝８５０ｎｍよりも長波長となるので、正面撮像光学系２００の光走査を被検眼が追従しづらくなる。したがって、被検眼の固視が安定した状態でのＯＣＴデータを取得できるので、結果として、良好なＯＣＴデータを取得できる。 In this case, the scanning light scanned on the fundus by the frontal imaging optical system 200 has a longer wavelength than λ = 850 nm, which is a wavelength region in which it is difficult for the eye to be inspected to see the scanned light. It becomes difficult for the subject to follow the scan. Therefore, it is possible to acquire OCT data in a state where the fixation of the eye to be inspected is stable, and as a result, good OCT data can be acquired.

＜第１の波長分離部材＞
なお、ＯＣＴ光学系１００における測定光の光路と、正面撮像光学系２００における走査光の光路とを分割するために波長分離を行う第１の波長分離部材３００（例えば、ダイクロイックミラー）が設けられてもよい。例えば、第１の波長分離部材３００は、ＯＣＴ光学系１００に用いられる測定光を反射し、正面撮像光学系２００に用いられる走査光を透過してもよい（図１参照）。また、これに限定されず、第１の波長分離部材３００は、ＯＣＴ光学系１００に用いられる測定光を透過し、正面撮像光学系２００に用いられる走査光を反射してもよい（図２参照）。 <First wavelength separation member>
A first wavelength separation member 300 (for example, a dichroic mirror) for performing wavelength separation is provided to separate the optical path of the measurement light in the OCT optical system 100 and the optical path of the scanning light in the front image pickup optical system 200. It is also good. For example, the first wavelength separation member 300 may reflect the measurement light used in the OCT optical system 100 and transmit the scanning light used in the front image pickup optical system 200 (see FIG. 1). Further, the first wavelength separation member 300 may transmit the measurement light used in the OCT optical system 100 and reflect the scanning light used in the front image pickup optical system 200 (see FIG. 2). ).

本実施例において、第１の波長分離部材３００は、例えば、被検眼にとって走査光を視認しづらい波長領域であって、正面撮像光学系２００による走査光の波長帯域よりも長く、ＯＣＴ光学系１００の測定光の波長帯域よりも短い波長帯域にカットオン波長が設定され、正面撮像光学系２００によって走査される走査光であってλ＝８５０ｎｍよりも長い波長帯域の光と、ＯＣＴ光学系１００の測定光とを分割する波長選択特性を有してもよい。 In the present embodiment, the first wavelength separation member 300 is, for example, a wavelength region in which it is difficult for the subject to visually recognize the scanning light, which is longer than the wavelength band of the scanning light by the front image pickup optical system 200, and is longer than the wavelength band of the scanning light by the front image pickup optical system 200. The cut-on wavelength is set to a wavelength band shorter than the wavelength band of the measurement light of the above, and the scanning light scanned by the front image pickup optical system 200 and having a wavelength band longer than λ = 850 nm and the OCT optical system 100. It may have a wavelength selection characteristic that separates the measurement light.

なお、上記構成において、より好ましくは、光源２０２としては、λ＝９００ｎｍよりも長く、ＯＣＴ光学系１００の測定光（例えば、λ＝９９０ｎｍ～１１００ｎｍ）よりも短い波長帯域に中心波長を持つ光を出射する光源が用いられてもよい。 In the above configuration, more preferably, the light source 202 is light having a center wavelength in a wavelength band longer than λ = 900 nm and shorter than the measurement light of the OCT optical system 100 (for example, λ = 990 nm to 1100 nm). An emitting light source may be used.

この場合、正面撮像光学系２００によって眼底上で走査される走査光は、被検眼にとって不可視領域であるλ＝９００ｎｍよりも長波長となるので、正面撮像光学系２００の光走査を被検眼が追従してしまうことを防止できる。したがって、正面撮像光学系２００による眼底観察に並行してＯＣＴデータが取得される場合（例えば、トラッキング制御）、又は、ＯＣＴデータの取得前の段階での正面撮像光学系２００を用いた測定光の位置決め又は撮影タイミングの決定の際、被検眼の固視がより安定した状態となり、結果として、より良好なＯＣＴデータを取得できる。なお、前述したように、ＯＣＴ光学系１００によって眼底上で走査される走査光も含めて不可視領域の光が用いられることで、ＯＣＴデータを得る際の固視をより安定させることできる。 In this case, the scanning light scanned on the fundus by the frontal imaging optical system 200 has a longer wavelength than λ = 900 nm, which is an invisible region for the eye to be inspected, and therefore the eye to be inspected follows the optical scanning of the frontal imaging optical system 200. It is possible to prevent it from happening. Therefore, when the OCT data is acquired in parallel with the observation of the fundus by the frontal imaging optical system 200 (for example, tracking control), or the measurement light using the frontal imaging optical system 200 at the stage before the acquisition of the OCT data. When positioning or determining the imaging timing, the fixation of the eye to be inspected becomes more stable, and as a result, better OCT data can be acquired. As described above, by using the light in the invisible region including the scanning light scanned on the fundus by the OCT optical system 100, it is possible to further stabilize the fixation when obtaining the OCT data.

この場合、第１の波長分離部材３００は、例えば、被検眼にとって不可視領域である波長領域であって、正面撮像光学系２００による走査光の波長帯域よりも長く、ＯＣＴ光学系１００の測定光の波長帯域よりも短い波長帯域にカットオン波長が設定され、正面撮像光学系２００によって走査される走査光であってλ＝９００ｎｍよりも長い波長帯域の光と、ＯＣＴ光学系１００の測定光とを分割する波長選択特性を有してもよい。 In this case, the first wavelength separation member 300 is, for example, a wavelength region invisible to the eye to be inspected, which is longer than the wavelength band of the scanning light by the front image pickup optical system 200, and is the measurement light of the OCT optical system 100. The cut-on wavelength is set in a wavelength band shorter than the wavelength band, and the scanning light scanned by the front image pickup optical system 200 and having a wavelength band longer than λ = 900 nm and the measurement light of the OCT optical system 100 are combined. It may have a wavelength selection characteristic to be divided.

＜前眼部観察光学系＞
追加的には、本実施例に係る眼底撮影装置において、例えば、被検眼の前眼部を観察するための前眼部観察光学系４００が設けられてもよい。この場合、前眼部観察光学系４００は、前眼部正面光源４０２と、撮像素子４０４とを主に備えてもよい。前眼部観察光学系４００は、対物レンズ２５を介して、前眼部照明光源４０２によって照明された被検眼前眼部の反射光を撮像素子４０４（例えば、二次元撮像素子）に導く。撮像素子４０４は、例えば、前眼部と共役な位置に配置されてもよい。 <Optical eye observation optical system>
In addition, in the fundus photography apparatus according to the present embodiment, for example, an anterior segment observation optical system 400 for observing the anterior segment of the eye to be inspected may be provided. In this case, the anterior eye portion observation optical system 400 may mainly include an anterior eye portion front light source 402 and an image pickup element 404. The anterior segment observation optical system 400 guides the reflected light of the anterior segment of the eye to be inspected illuminated by the anterior segment illumination light source 402 to the image pickup element 404 (for example, a two-dimensional image pickup element) via the objective lens 25. The image pickup device 404 may be arranged at a position conjugate with the anterior eye portion, for example.

眼底撮影装置は、撮像素子４０４からの撮像信号に基づいて前眼部正面画像を得ることができる。前眼部照明光源４０２としては、例えば、λ＝９３０ｎｍ～９５０ｎｍの波長帯域に中心波長を持つ光源が用いられてもよい。また、これに限定されず、前眼部照明光源４０２としては、λ＝９３０ｎｍ～９５０ｎｍから外れた波長帯域に中心波長を持つ光源であって、λ＝９３０ｎｍ～９５０ｎｍの波長帯域を少なくとも含む光を発する光源が用いられてもよい。なお、本実施例では、前眼部観察光学系４００は、λ＝９３０ｎｍ～９５０ｎｍの波長帯域を少なくとも含む反射光を撮像素子４０４に導く。 The fundus photography device can obtain a frontal image of the anterior segment of the eye based on an image pickup signal from the image pickup element 404. As the front eye illumination light source 402, for example, a light source having a central wavelength in the wavelength band of λ = 930 nm to 950 nm may be used. Further, the front eye illumination light source 402 is not limited to this, and is a light source having a central wavelength in a wavelength band deviating from λ = 930 nm to 950 nm, and includes light having at least a wavelength band of λ = 930 nm to 950 nm. A light source that emits light may be used. In this embodiment, the anterior eye observation optical system 400 guides reflected light including at least a wavelength band of λ = 930 nm to 950 nm to the image pickup element 404.

＜第１の波長分離部材＞
眼底撮影装置において、前眼部観察光学系４００が設けられた場合、例えば、第１の波長分離部材３００は、ＯＣＴ光学系１００における測定光の光路と、正面撮像光学系２００における走査光の光路とを分割すると共に、ＯＣＴ光学系１００と正面撮像光学系２００のいずれかの光路に対して前眼部観察光学系４００の光路を分割するために波長分離を行ってもよい。 <First wavelength separation member>
When the anterior segment observation optical system 400 is provided in the fundus imaging apparatus, for example, the first wavelength separation member 300 includes an optical path of measurement light in the OCT optical system 100 and an optical path of scanning light in the front image pickup optical system 200. In addition to dividing the optical path, wavelength separation may be performed to divide the optical path of the anterior segment observation optical system 400 with respect to the optical path of either the OCT optical system 100 or the frontal imaging optical system 200.

第１の波長分離部材３００は、ＯＣＴ光学系１００に用いられる測定光と前眼部照明光源４０２による前眼部反射光を反射し、正面撮像光学系２００に用いられる走査光を透過してもよい（図１参照）。この場合、第１の波長分離部材３００は、例えば、被検眼にとって走査光を視認しづらい波長領域であって、正面撮像光学系２００による走査光の波長帯域よりも長く、ＯＣＴ光学系１００の測定光の波長帯域と前眼部照明光源４０２による前眼部反射光の波長帯域（λ＝９３０ｎｍ～９５０ｎｍの波長帯域）よりも短い波長帯域にカットオン波長が設定され、正面撮像光学系２００によって走査される走査光であってλ＝８５０ｎｍ（好ましくは、λ＝９００ｎｍ）よりも長い波長帯域の光と、ＯＣＴ光学系１００の測定光及び前眼部照明光源４０２による前眼部反射光を分割する波長選択特性を有してもよい。 Even if the first wavelength separation member 300 reflects the measurement light used in the OCT optical system 100 and the anterior segment reflected light by the anterior segment illumination light source 402 and transmits the scanning light used in the front image pickup optical system 200. Good (see Figure 1). In this case, the first wavelength separating member 300 is, for example, a wavelength region in which it is difficult for the subject to visually recognize the scanning light, which is longer than the wavelength band of the scanning light by the front image pickup optical system 200, and is measured by the OCT optical system 100. The cut-on wavelength is set to a wavelength band shorter than the light wavelength band and the wavelength band of the front eye reflected light by the front eye illumination light source 402 (λ = 930 nm to 950 nm wavelength band), and is scanned by the front image pickup optical system 200. The scanning light to be scanned is separated from the light having a wavelength band longer than λ = 850 nm (preferably λ = 900 nm), the measurement light of the OCT optical system 100, and the anterior segment reflected light by the anterior segment illumination light source 402. It may have a wavelength selection characteristic.

また、これに限定されず、第１の波長分離部材３００は、ＯＣＴ光学系１００に用いられる測定光を透過し、正面撮像光学系２００に用いられる走査光と前眼部照明光源４０２による前眼部反射光を反射してもよい（図２参照）。この場合、第１の波長分離部材３００は、例えば、被検眼にとって走査光を視認しづらい波長領域であって、正面撮像光学系２００による走査光の波長帯域と前眼部照明光源４０２による前眼部反射光の波長帯域（λ＝９３０ｎｍ～９５０ｎｍの波長帯域）よりも長く、ＯＣＴ光学系１００の測定光の波長帯域よりも短い波長帯域にカットオン波長が設定され、正面撮像光学系２００によって走査される走査光であってλ＝８５０ｎｍ（好ましくは、λ＝９００ｎｍ）よりも長い波長帯域の光及び前眼部照明光源４０２による前眼部反射光と、ＯＣＴ光学系１００の測定光を分割する波長選択特性を有してもよい。 Further, the first wavelength separating member 300 is not limited to this, and the first wavelength separating member 300 transmits the measurement light used in the OCT optical system 100, and the scanning light used in the front image pickup optical system 200 and the anterior eye by the anterior segment illumination light source 402. Partially reflected light may be reflected (see FIG. 2). In this case, the first wavelength separating member 300 is, for example, a wavelength region in which it is difficult for the subject to visually recognize the scanning light, and is the wavelength band of the scanning light by the front image pickup optical system 200 and the front eye by the front eye illumination light source 402. The cut-on wavelength is set to a wavelength band longer than the wavelength band of the partially reflected light (λ = 930 nm to 950 nm) and shorter than the wavelength band of the measurement light of the OCT optical system 100, and scanned by the front image pickup optical system 200. The scanning light to be scanned is divided into light having a wavelength band longer than λ = 850 nm (preferably λ = 900 nm), reflected light from the anterior segment of the eye by the anterior segment illumination light source 402, and measurement light of the OCT optical system 100. It may have a wavelength selection characteristic.

＜第２の波長分離部材＞
眼底撮影装置において、前眼部観察光学系４００が設けられた場合、第１の波長分離部材によって分割されたＯＣＴ光学系１００と正面撮像光学系２００のいずれかの光路に対し、前眼部観察光学系４００の光路を分割するために波長分離を行う第２の波長分離部材３５０が設けられてもよい。この場合、例えば、第２の波長分離部材３５０は、ＯＣＴ光学系１００の光路と、前眼部観察光学系４００の光路とを分割するために波長分離を行ってもよい（図１参照）。もしくは、第２の波長分離部材３５０は、正面撮像光学系２００の光路と、前眼部観察光学系４００の光路とを分割するために波長分離を行ってもよい。 <Second wavelength separation member>
When the anterior segment observation optical system 400 is provided in the fundus photography apparatus, the anterior segment observation is performed with respect to either the optical path of the OCT optical system 100 or the frontal imaging optical system 200 divided by the first wavelength separation member. A second wavelength separation member 350 that performs wavelength separation may be provided in order to divide the optical path of the optical system 400. In this case, for example, the second wavelength separation member 350 may perform wavelength separation in order to divide the optical path of the OCT optical system 100 and the optical path of the anterior segment observation optical system 400 (see FIG. 1). Alternatively, the second wavelength separation member 350 may perform wavelength separation in order to divide the optical path of the frontal imaging optical system 200 and the optical path of the anterior segment observation optical system 400.

例えば、第２の波長分離部材３００は、第１の波長分離部材によって分割されたＯＣＴ光学系１００と正面撮像光学系２００のいずれか一方に用いられる光を透過し、前眼部照明光源４０２による前眼部反射光を反射する波長特性を有してもよい。例えば、第２の波長分離部材３００は、第１の波長分離部材によって分割されたＯＣＴ光学系１００と正面撮像光学系２００のいずれか一方に用いられる光を反射し、前眼部照明光源４０２による前眼部反射光を透過する波長特性を有してもよい。 For example, the second wavelength separation member 300 transmits the light used for either the OCT optical system 100 or the front image pickup optical system 200 divided by the first wavelength separation member, and is transmitted by the anterior segment illumination light source 402. It may have a wavelength characteristic that reflects the light reflected from the anterior segment of the eye. For example, the second wavelength separation member 300 reflects the light used for either the OCT optical system 100 or the front image pickup optical system 200 divided by the first wavelength separation member, and is driven by the anterior segment illumination light source 402. It may have a wavelength characteristic that transmits the reflected light in the anterior segment of the eye.

ＯＣＴ光学系１００に対して前眼部観察光学系４００の光路を分割する場合（図１参照）、第２の波長分離部材３５０は、例えば、前眼部照明光源４０２による前眼部反射光の波長帯域（λ＝９３０ｎｍ～９５０ｎｍの波長帯域）よりも長く、ＯＣＴ光学系１００の測定光の波長帯域よりも短い波長帯域にカットオン波長が設定され、前眼部照明光源４０２による前眼部反射光の波長帯域の光と、ＯＣＴ光学系１００の測定光とを分割する波長選択特性を有してもよい。 When the optical path of the anterior segment observation optical system 400 is divided with respect to the OCT optical system 100 (see FIG. 1), the second wavelength separation member 350 is, for example, of the anterior segment reflected light by the anterior segment illumination light source 402. The cut-on wavelength is set in a wavelength band longer than the wavelength band (λ = 930 nm to 950 nm wavelength band) and shorter than the wavelength band of the measurement light of the OCT optical system 100, and the anterior segment reflection by the anterior segment illumination light source 402 is set. It may have a wavelength selection characteristic that divides the light in the wavelength band of the light and the measurement light of the OCT optical system 100.

正面撮像光学系２００に対して前眼部観察光学系４００の光路を分割する場合（図２参照）、第２の波長分離部材３５０は、例えば、前眼部照明光源４０２による前眼部反射光の波長帯域（λ＝９３０ｎｍ～９５０ｎｍの波長帯域）よりも短く、正面撮像光学系２００の走査光の波長帯域よりも長い波長帯域にカットオン波長が設定され、前眼部照明光源４０２による前眼部反射光の波長帯域の光と、正面撮像光学系４００の走査光とを分割する波長選択特性を有してもよい。 When the optical path of the anterior segment observation optical system 400 is divided with respect to the frontal image pickup optical system 200 (see FIG. 2), the second wavelength separation member 350 is, for example, the anterior segment reflected light by the anterior segment illumination light source 402. The cut-on wavelength is set to a wavelength band shorter than the wavelength band (λ = 930 nm to 950 nm wavelength band) and longer than the wavelength band of the scanning light of the front image pickup optical system 200, and the front eye is set by the front eye illumination light source 402. It may have a wavelength selection characteristic that separates the light in the wavelength band of the partially reflected light and the scanning light of the front image pickup optical system 400.

＜広角化対応＞
なお、正面撮像光学系２００の光源２０２として、λ＝９００ｎｍよりも長く、ＯＣＴ光学系１００の測定光（例えば、λ＝９９０ｎｍ～１１００ｎｍ）よりも短い波長帯域に中心波長を持つ光を出射する光源が用いられる場合、９００ｎｍ～１０００ｎｍの間において、正面撮像光学系２００の走査光と、前眼部反射光と、ＯＣＴ光学系１００の測定光とを分離できるように、第１の波長分離部材３００と第２の波長分離部材３５０のカットオン波長を設定する必要がある。 <Wide-angle support>
As the light source 202 of the front image pickup optical system 200, a light source that emits light having a center wavelength in a wavelength band longer than λ = 900 nm and shorter than the measurement light of the OCT optical system 100 (for example, λ = 990 nm to 1100 nm). When is used, the first wavelength separation member 300 is capable of separating the scanning light of the front image pickup optical system 200, the reflected light of the anterior segment of the eye, and the measurement light of the OCT optical system 100 between 900 nm and 1000 nm. And it is necessary to set the cut-on wavelength of the second wavelength separation member 350.

近年、ＯＣＴ光学系１００及び正面撮像光学系２００においては、撮影画角（走査画角）の広角化が進んでいる。撮影画角が広角化される場合、第１の波長分離部材３００と第２の波長分離部材３５０に対するＯＣＴ光学系１００（又は正面撮像光学系２００）の入射角範囲が拡大する。この場合、波長分離部材に対する入射角が大きくなると、ＯＣＴ光学系１００（又は正面撮像光学系２００）に用いられる光は、第１の波長分離部材３００と第２の波長分離部材３５０によって光路が分割される際、透過率・反射率特性が短波長側にスライドしていく。すなわち、ＯＣＴ光学系１００の測定光と前眼部反射光とを分離するためのカットオン波長、又は、ＳＬＯ光学系２００の走査光と前眼部反射光とを分離するためのカットオン波長が短波長側にシフトしていく。また、波長分離部材に対する入射角が小さくなると、透過率・反射率特性は、長波長側にシフトしていく。 In recent years, in the OCT optical system 100 and the front image pickup optical system 200, the shooting angle of view (scanning angle of view) has been widened. When the shooting angle of view is widened, the incident angle range of the OCT optical system 100 (or the front image pickup optical system 200) with respect to the first wavelength separation member 300 and the second wavelength separation member 350 is expanded. In this case, when the incident angle with respect to the wavelength separation member becomes large, the light used in the OCT optical system 100 (or the front image pickup optical system 200) is divided into an optical path by the first wavelength separation member 300 and the second wavelength separation member 350. At that time, the transmittance / reflectance characteristics slide toward the short wavelength side. That is, the cut-on wavelength for separating the measurement light of the OCT optical system 100 and the reflected light of the anterior segment of the eye, or the cut-on wavelength for separating the scanning light of the SLO optical system 200 and the reflected light of the anterior segment of the eye. It shifts to the short wavelength side. Further, as the angle of incidence on the wavelength separation member becomes smaller, the transmittance / reflectance characteristics shift to the long wavelength side.

この場合、カットオン波長の短波長側、長波長側へのスライドを考慮して、正面撮像光学系２００の光源２０２として、λ＝９００ｎｍよりも長く、かつ、λ＝９１０ｎｍよりも短い波長帯域（不可視領域における短波長領域）に中心波長を持つ光を出射する光源とすることで、前眼部観察光学系４００とのカットオン波長が短波長側にシフトしても、正面撮像光学系２００の走査光の光量損失を抑制しやすくなる。これによって、例えば、広画角の眼底正面画像を確実に得ることができ、また前眼部反射光に基づいて生成される前眼部画像内での光量ムラが低減される。 In this case, in consideration of sliding the cut-on wavelength to the short wavelength side and the long wavelength side, the light source 202 of the frontal imaging optical system 200 has a wavelength band longer than λ = 900 nm and shorter than λ = 910 nm. By using a light source that emits light having a central wavelength in the short wavelength region in the invisible region), even if the cut-on wavelength with the anterior segment observation optical system 400 shifts to the short wavelength side, the front image pickup optical system 200 It becomes easy to suppress the light amount loss of the scanning light. As a result, for example, a wide-angle frontal image of the fundus can be reliably obtained, and unevenness in the amount of light in the image of the anterior segment of the eye generated based on the reflected light of the anterior segment of the eye can be reduced.

また、前眼部観察光学系４００において、被検眼前眼部の反射光として、λ＝９３０ｎｍ～９５０ｎｍの波長帯域を少なくとも含む反射光を用いることで、ＯＣＴ光学系１００とのカットオン波長が短波長側にシフトしても、ＯＣＴ光学系１００の測定光の光量損失を抑制しやすくなる。これによって、例えば、広帯域の測定光を用いて解像度の高い広画角のＯＣＴデータを得ることができ、また前眼部反射光に基づいて生成される前眼部画像内での光量ムラが低減される。 Further, in the anterior segment observation optical system 400, the cut-on wavelength with the OCT optical system 100 is shortened by using the reflected light including at least the wavelength band of λ = 930 nm to 950 nm as the reflected light of the anterior segment of the eye to be inspected. Even if the wavelength is shifted to the wavelength side, it becomes easy to suppress the light amount loss of the measured light of the OCT optical system 100. This makes it possible to obtain high-resolution wide-angle OCT data using, for example, wide-band measurement light, and reduce unevenness in the amount of light in the front-eye image generated based on the front-eye reflected light. Will be done.

この場合、第１の波長分離部材３００及び第２の波長分離部材３５０は、被検眼前眼部の反射光として、λ＝９３０ｎｍ～９５０ｎｍの波長帯域を少なくとも含む反射光を撮像素子４０４に導くように波長特性が設定されてもよい。 In this case, the first wavelength separating member 300 and the second wavelength separating member 350 guide the reflected light including at least the wavelength band of λ = 930 nm to 950 nm to the image pickup element 404 as the reflected light of the anterior segment of the eye to be inspected. The wavelength characteristic may be set to.

図１の光学配置の場合、例えば、第２の波長分離部材３５０において、λ＝９５０ｎｍよりも長い波長帯域（例えば、λ＝９６０ｎｍをカットオン波長として設定する）であって、ＯＣＴ光学系１００の測定光の波長帯域よりも短い波長帯域をカットオン波長に設定（図３参照）することによって、前眼部観察光学系４００を設けつつ、ＯＣＴ光学系１００の広角化に対応できる。さらに、光路分割に伴う正面撮像光学系２００に用いられる光の光量損失を補うために、第１の波長分離部材３００において、λ＝９３０ｎｍよりも短い波長帯域（例えば、λ＝９２５ｎｍをカットオン波長として設定する）であって、正面撮像光学系２００の走査光の波長帯域よりも長い波長帯域をカットオン波長に設定する（図４参照）ことによって、前眼部観察光学系４００を設けつつ、正面撮像光学系２００の広角化に対応できる（例えば、画角５０度以上の撮影画角を確保できる）。 In the case of the optical arrangement of FIG. 1, for example, in the second wavelength separation member 350, the wavelength band longer than λ = 950 nm (for example, λ = 960 nm is set as the cut-on wavelength), and the OCT optical system 100 is used. By setting a wavelength band shorter than the wavelength band of the measurement light as the cut-on wavelength (see FIG. 3), it is possible to widen the angle of the OCT optical system 100 while providing the anterior segment observation optical system 400. Further, in order to compensate for the light amount loss of the light used in the front image pickup optical system 200 due to the optical path division, the wavelength band shorter than λ = 930 nm (for example, λ = 925 nm is the cut-on wavelength) in the first wavelength separation member 300. By setting the cut-on wavelength to a wavelength band longer than the wavelength band of the scanning light of the front image pickup optical system 200 (see FIG. 4), the front eye portion observation optical system 400 is provided. It is possible to cope with widening of the front image pickup optical system 200 (for example, it is possible to secure a shooting angle of 50 degrees or more).

また、図２の光学配置の場合、例えば、第１の波長分離部材３００において、λ＝９５０ｎｍよりも長い波長帯域であって、ＯＣＴ光学系１００の測定光の波長帯域よりも短い波長帯域をカットオン波長に設定することによって、前眼部観察光学系４００を設けつつ、ＯＣＴ光学系１００の広角化に対応できる。さらに、第２の波長分離部材３５０において、λ＝９３０ｎｍよりも短い波長帯域であって、正面撮像光学系２００の走査光の波長帯域よりも長い波長帯域をカットオン波長に設定することによって、前眼部観察光学系４００を設けつつ、正面撮像光学系２００の広角化に対応できる。 Further, in the case of the optical arrangement of FIG. 2, for example, in the first wavelength separation member 300, a wavelength band longer than λ = 950 nm and shorter than the wavelength band of the measurement light of the OCT optical system 100 is cut. By setting the wavelength to on, it is possible to widen the angle of the OCT optical system 100 while providing the anterior segment observation optical system 400. Further, in the second wavelength separating member 350, a wavelength band shorter than λ = 930 nm and longer than the wavelength band of the scanning light of the front image pickup optical system 200 is set as the cut-on wavelength. It is possible to widen the angle of the front image pickup optical system 200 while providing the eye observation optical system 400.

＜可視光を用いた光学系の追加＞
なお、眼底撮影装置において、正面撮像光学系２００として、被検眼にとって走査光を視認しづらい波長帯域の光を用いたことによって、可視光の波長領域が広帯域に確保できる）。 <Addition of optical system using visible light>
In the fundus photography apparatus, the frontal imaging optical system 200 uses light in a wavelength band in which it is difficult for the eye to be inspected to visually recognize the scanning light, so that the wavelength region of visible light can be secured in a wide band).

そこで、本実施例に係る眼底撮影装置としては、例えば、可視光により眼底の撮影又は眼底の測定を行う可視光学系５００が追加的に設けられてもよい（例えば、図５、図６参照。この場合、可視光学系５００は、正面撮像光学系２００に用いられる光よりも短波長側に中心波長を持つ可視光を発する可視光源を備えてもよい。この場合、可視光学系５００は、例えば、眼底撮影又は眼底刺激を行うために用いられてもよい。また、可視光学系５００として、例えば、被検眼を固視させるための固視標（固視灯を含む）を呈示する固光学系が設けられてもよい。 Therefore, as the fundus imaging device according to the present embodiment, for example, a visible optical system 500 for photographing or measuring the fundus with visible light may be additionally provided (see, for example, FIGS. 5 and 6). In this case, the visible optical system 500 may include a visible light source that emits visible light having a central wavelength on the shorter wavelength side than the light used for the frontal imaging optical system 200. In this case, the visible optical system 500 may be provided, for example. It may be used for fundus photography or fundus stimulation. Further, as the visible optical system 500, for example, a solid optical system presenting a fixation target (including a fixation lamp) for fixing the eye to be inspected. May be provided.

可視光学系５００としては、例えば、可視光にて眼底を撮影するための撮影光学系であってもよい。撮影光学系としては、例えば、眼底カメラ方式の光学系であってもよいし、ＳＬＯ方式の光学系であってもよい。このような可視光学系を備える眼底撮影装置において、正面撮像光学系２００は、例えば、正面撮像光学系２００によって撮像された眼底正面画像（眼底観察画像）による撮影位置、撮影タイミングの設定等に用いることができる。この場合、例えば、正面撮像光学系の走査光が、走査光を視認しづらい波長領域（好ましくは不可視領域）であることによって、例えば、走査光によって被検眼が追従しづらくなり、良好な可視眼底画像を取得できる。より詳細には、走査型の正面撮像光学系２００によって得られた鮮明な正面画像を用いて眼底を観察できるため、撮影タイミング、撮影位置の確認等を正確に行うことができると共に、走査型の正面撮像光学系２００の走査光が視認しづらく、被検眼が走査光を追従しづらくなり、可視光による眼底撮影を確実に行うことが可能となる。 The visible optical system 500 may be, for example, a photographing optical system for photographing the fundus with visible light. The photographing optical system may be, for example, a fundus camera type optical system or an SLO type optical system. In the fundus photography apparatus provided with such a visible optical system, the frontal imaging optical system 200 is used, for example, for setting the imaging position and imaging timing of the fundus frontal image (fundus observation image) captured by the frontal imaging optical system 200. be able to. In this case, for example, the scanning light of the front image pickup optical system is in a wavelength region (preferably an invisible region) in which the scanning light is difficult to see, so that the scanning light makes it difficult for the eye to be inspected to follow, and a good visible fundus. You can get the image. More specifically, since the fundus can be observed using the clear front image obtained by the scanning type frontal imaging optical system 200, it is possible to accurately confirm the shooting timing, the shooting position, and the like, and the scanning type. The scanning light of the front image pickup optical system 200 is difficult to visually recognize, and it is difficult for the eye to be inspected to follow the scanning light, so that it is possible to reliably perform fundus photography with visible light.

可視光学系５００としては、可視光により眼底に刺激点を投影して視野測定を行うための測定光学系であってもよい。このような可視光学系を備える眼底撮影装置において、正面撮像光学系は、例えば、正面撮像光学系によって撮像された眼底正面画像上での刺激位置の設定、正面撮像光学系によって撮像された眼底正面画像に基づく刺激点の位置補正（トラッキング）等に用いることができる。この場合、正面撮像光学系の走査光が、走査光を視認しづらい波長領域（好ましくは不可視領域）であることによって、例えば、走査光によって被検眼が追従しづらくなり、良好な視野データを取得できる。より詳細には、走査型の正面撮像光学系２００によって得られた鮮明な正面画像を用いて視野の測定点を設定できるため、測定点の設定を正確に行うことができると共に、走査光が視認しづらく、被検眼が走査光を追従しづらくなり、視野測定を確実に行うことが可能となる。 The visible optical system 500 may be a measurement optical system for projecting a stimulus point on the fundus of the eye with visible light to perform visual field measurement. In the fundus photography apparatus provided with such a visible optical system, the frontal imaging optical system is, for example, setting a stimulation position on the fundus frontal image captured by the frontal imaging optical system, and the frontal fundus imaged by the frontal imaging optical system. It can be used for position correction (tracking) of a stimulus point based on an image. In this case, since the scanning light of the front image pickup optical system is in a wavelength region (preferably invisible region) in which the scanning light is difficult to see, for example, the scanning light makes it difficult for the eye to be inspected to follow, and good visual field data is acquired. can. More specifically, since the measurement point of the visual field can be set using the clear front image obtained by the scanning type frontal imaging optical system 200, the measurement point can be set accurately and the scanning light can be visually recognized. It is difficult for the eye to be inspected to follow the scanning light, and it becomes possible to reliably perform visual field measurement.

眼底撮影装置において、可視光学系５００が設けられた場合、正面撮像光学系２００に設けられた走査部２０８と被検眼との間に設けられ、正面撮像光学系２００及び可視光学系５００の光路と、ＯＣＴ光学系１００の光路とを分割するための波長分離を行う第３の波長分離部材３８０が設けられてもよい。 When the visible optical system 500 is provided in the fundus imaging device, it is provided between the scanning unit 208 provided in the front image pickup optical system 200 and the eye to be inspected, and is provided with the optical path of the front image pickup optical system 200 and the visible optical system 500. , A third wavelength separation member 380 that performs wavelength separation for dividing the optical path of the OCT optical system 100 may be provided.

図５は、図１の光学配置の眼底撮影装置において可視光学系５００を設けた場合の一例であり、第３の波長分離部材３８０は、第１の波長分離部材３００の透過方向であって、第１の波長分離部材３００よりも上流（光源側）に配置され、可視光学系５００の光路と、正面撮像光学系２００の光路とを分割するようにしてもよい。 FIG. 5 is an example of the case where the visible optical system 500 is provided in the fundus imaging apparatus having the optical arrangement of FIG. 1, and the third wavelength separation member 380 is the transmission direction of the first wavelength separation member 300. It may be arranged upstream (on the light source side) from the first wavelength separation member 300 to divide the optical path of the visible optical system 500 and the optical path of the frontal imaging optical system 200.

図６は、図２の光学配置の眼底撮影装置において可視光学系５００を設けた場合の一例であり、第３の波長分離部材３８０は、第２の波長分離部材３５０の透過方向であって、第２の波長分離部材３５０よりも上流（光源側）に配置され、可視光学系５０の光路と、正面撮像光学系２００の光路とを分割するようにしてもよい。 FIG. 6 is an example of the case where the visible optical system 500 is provided in the fundus imaging apparatus having the optical arrangement of FIG. 2, and the third wavelength separation member 380 is the transmission direction of the second wavelength separation member 350. It may be arranged upstream (on the light source side) of the second wavelength separation member 350 to divide the optical path of the visible optical system 50 and the optical path of the frontal imaging optical system 200.

図５、図６に示すような光学配置によれば、各波長分離部材３００、３５０、３８０は、バンドバスとならずに対応できるため、効率的な製造が可能となる。 According to the optical arrangement as shown in FIGS. 5 and 6, the wavelength separating members 300, 350, and 380 can be used without forming a band bus, so that efficient manufacturing is possible.

＜変容例＞
なお、上記実施例においては、ＯＣＴ光学系１００と、正面撮像光学系２００と、を備える眼底撮影装置において、正面撮像光学系２００の走査光として被検眼に視認しづらい波長領域（好ましくは不可視領域）を用いる場合を示したが、これに限定されない。 <Example of transformation>
In the above embodiment, in the fundus photography apparatus including the OCT optical system 100 and the frontal imaging optical system 200, the wavelength region (preferably invisible region) that is difficult for the eye to be visually recognized as the scanning light of the frontal imaging optical system 200. ) Is used, but the present invention is not limited to this.

例えば、可視光学系５００と、正面撮像光学系２００と、を備える眼底撮影装置において、正面撮像光学系２００の走査光として被検眼に視認しづらい波長領域（好ましくは不可視領域）を用いるようにしてもよい。これによって、例えば、走査光によって被検眼が追従しづらくなり、可視光による撮影又は測定等を確実に行うことができる。 For example, in a fundus photography apparatus including a visible optical system 500 and a frontal imaging optical system 200, a wavelength region (preferably an invisible region) that is difficult to see by the eye to be inspected is used as scanning light of the frontal imaging optical system 200. It is also good. As a result, for example, it becomes difficult for the eye to be inspected to follow due to the scanning light, and it is possible to reliably perform imaging or measurement with visible light.

第１の実施例に係る眼底撮影装置の光学系を示す図である。It is a figure which shows the optical system of the fundus photography apparatus which concerns on 1st Embodiment. 第２の実施例に係る眼底撮影装置の光学系を示す図である。It is a figure which shows the optical system of the fundus photography apparatus which concerns on 2nd Embodiment. 本実施例に係る第２の波長分離部材のカットオン波長の一例を示す図である。It is a figure which shows an example of the cut-on wavelength of the 2nd wavelength separation member which concerns on this Example. 本実施例に係る第１の波長分離部材のカットオン波長の一例を示す図である。It is a figure which shows an example of the cut-on wavelength of the 1st wavelength separation member which concerns on this Example. 第３の実施例に係る眼底撮影装置の光学系を示す図である。It is a figure which shows the optical system of the fundus photography apparatus which concerns on 3rd Example. 第４の実施例に係る眼底撮影装置の光学系を示す図である。It is a figure which shows the optical system of the fundus photography apparatus which concerns on 4th Embodiment.

１００ＯＣＴ光学系
２００正面撮像光学系
３００第１の波長分離部材
３５０第２の波長分離部材
３８０第３の波長分離部材
４００前眼部観察光学系
５００可視光学系

100 OCT optical system 200 Frontal imaging optical system 300 First wavelength separation member 350 Second wavelength separation member 380 Third wavelength separation member 400 Front eye observation optical system 500 Visible optical system

Claims

被検眼眼底に照射された測定光と参照光によるＯＣＴデータを取得するためのＯＣＴ光学系と、被検眼眼底上で光を走査することにより眼底正面画像を撮像するための正面撮像光学系と、を備える眼底撮影装置において、
前記正面撮像光学系によって被検眼眼底上で走査される走査光は、被検眼にとって走査光を視認しづらい波長領域であるλ＝８５０ｎｍよりも長波長であることを特徴とする眼底撮影装置。 An OCT optical system for acquiring OCT data from the measurement light and reference light applied to the fundus of the eye to be inspected, and a frontal image pickup optical system for capturing a frontal image of the fundus by scanning the light on the fundus of the eye to be inspected. In a fundus photography device equipped with
A fundus photography apparatus characterized in that the scanning light scanned on the fundus of the eye to be inspected by the frontal imaging optical system has a wavelength longer than λ = 850 nm, which is a wavelength region in which it is difficult for the eye to be inspected to visually recognize the scanned light.

前記正面撮像光学系によって被検眼眼底上で走査される走査光は、
被検眼にとって不可視領域であるλ＝９００ｎｍよりも長波長であることを特徴とする請求項１の眼底撮影装置。 The scanning light scanned on the fundus of the eye to be inspected by the frontal imaging optical system is
The fundus photography apparatus according to claim 1, wherein the wavelength is longer than λ = 900 nm, which is an invisible region for the eye to be inspected.

ＯＣＴ光学系に用いられる光源は、λ＝１０００ｎｍ～１１００ｎｍの間に中心波長を持つ測定光を出射する光源であることを特徴とする請求項１～２のいずれかの眼底撮影装置。 The fundus photography apparatus according to any one of claims 1 and 2, wherein the light source used in the OCT optical system is a light source that emits measurement light having a center wavelength between λ = 1000 nm and 1100 nm.

前眼部照明光源によって照明された被検眼前眼部の反射光を撮像素子に導くための前眼部観察光学系と、
前記ＯＣＴ光学系における測定光の光路と、前記正面撮像光学系における走査光の光路とを分割すると共に、前記ＯＣＴ光学系と前記正面撮像光学系のいずれかの光路に対して前記前眼部観察光学系の光路を分割するために波長分離を行う第１の波長分離部材と、
前記第１の波長分離部材によって分割された前記ＯＣＴ光学系と前記正面撮像光学系のいずれかの光路に対し、前記前眼部観察光学系の光路を分割するために波長分離を行う第２の波長分離部材と、
を備えることを特徴とする請求項２～３のいずれかの眼底撮影装置。 Anterior segment observation optical system for guiding the reflected light of the anterior segment of the eye to be inspected illuminated by the anterior segment illumination light source to the image pickup element, and the anterior segment observation optical system.
The optical path of the measurement light in the OCT optical system and the optical path of the scanning light in the front image pickup optical system are divided, and the front eye portion is observed with respect to the optical path of either the OCT optical system or the front image pickup optical system. A first wavelength separation member that performs wavelength separation to divide the optical path of the optical system,
A second wavelength separation is performed in order to divide the optical path of the anterior segment observation optical system into the optical path of either the OCT optical system or the frontal imaging optical system divided by the first wavelength separation member. Wavelength separator and
The fundus photography apparatus according to any one of claims 2 to 3, further comprising.

前記第１の波長分離部材及び前記第２の波長分離部材は、前記被検眼前眼部の反射光として、λ＝９３０ｎｍ～９５０ｎｍの波長帯域を少なくとも含む反射光を前記撮像素子に導くように波長特性が設定されていることを特徴とする請求項４の眼底撮影装置。 The first wavelength separating member and the second wavelength separating member have wavelengths such that the reflected light including at least the wavelength band of λ = 930 nm to 950 nm is guided to the image pickup element as the reflected light of the anterior segment of the eye to be inspected. The fundus photography apparatus according to claim 4, wherein the characteristics are set.

前記正面撮像光学系に用いられる光よりも短波長側に中心波長を持つ可視光を発する可視光源を備える可視光学系と、
前記正面撮像光学系に設けられた走査部と被検眼との間に設けられ、前記正面撮像光学系及び前記可視光学系の光路と、前記ＯＣＴ光学系の光路とを分割するための波長分離を行う第３の波長分離部材と、
を備えることを特徴とする請求項１～５のいずれかの眼底撮影装置。 A visible optical system including a visible light source that emits visible light having a central wavelength on the shorter wavelength side than the light used for the frontal imaging optical system, and a visible optical system.
A wavelength separation is provided between the scanning unit provided in the front image pickup optical system and the eye to be inspected to divide the optical path of the front image pickup optical system and the visible optical system and the optical path of the OCT optical system. With the third wavelength separation member to be performed,
The fundus photography apparatus according to any one of claims 1 to 5.

可視光により被検眼眼底に刺激点を投影して視野測定を行うための測定光学系と、被検眼眼底上で光を走査することにより眼底正面画像を撮像するための正面撮像光学系と、を備える眼底撮影装置において、
前記正面撮像光学系によって被検眼眼底上で走査される走査光は、被検眼にとって走査光を視認しづらい波長領域であるλ＝８５０ｎｍよりも長波長であることを特徴とする眼底撮影装置。 A measurement optical system for projecting a stimulus point on the fundus of the eye to be inspected with visible light to measure the field of view, and a frontal imaging optical system for capturing a frontal image of the fundus by scanning light on the fundus of the eye to be inspected. In the fundus photography device provided
A fundus photography apparatus characterized in that the scanning light scanned on the fundus of the eye to be inspected by the frontal imaging optical system has a wavelength longer than λ = 850 nm, which is a wavelength region in which it is difficult for the eye to be inspected to visually recognize the scanned light.

可視光により被検眼眼底を撮影するための可視撮影光学系と、被検眼眼底上で光を走査することにより眼底正面画像を撮像するための正面撮像光学系と、を備える眼底撮影装置において、
前記正面撮像光学系によって被検眼眼底上で走査される走査光は、被検眼にとって走査光を視認しづらい波長領域であるλ＝８５０ｎｍよりも長波長であることを特徴とする眼底撮影装置。 In a fundus photography apparatus including a visible photographing optical system for photographing the fundus of the eye to be inspected with visible light and a frontal imaging optical system for capturing an image of the front of the fundus by scanning light on the fundus of the eye to be inspected.
A fundus photography apparatus characterized in that the scanning light scanned on the fundus of the eye to be inspected by the frontal imaging optical system has a wavelength longer than λ = 850 nm, which is a wavelength region in which it is difficult for the eye to be inspected to visually recognize the scanned light.

前記正面撮像光学系によって被検眼眼底上で走査される走査光は、
被検眼にとって不可視領域であるλ＝９００ｎｍよりも長波長であることを特徴とする請求項７～８のいずれかの眼底撮影装置。 The scanning light scanned on the fundus of the eye to be inspected by the frontal imaging optical system is
The fundus photography apparatus according to any one of claims 7 to 8, wherein the wavelength is longer than λ = 900 nm, which is an invisible region for the eye to be inspected.