JP4245738B2

JP4245738B2 - Fundus camera

Info

Publication number: JP4245738B2
Application number: JP19829499A
Authority: JP
Inventors: 孝佳鈴木; 幸治小林
Original assignee: Kowa Co Ltd
Current assignee: Kowa Co Ltd
Priority date: 1999-07-13
Filing date: 1999-07-13
Publication date: 2009-04-02
Anticipated expiration: 2019-07-13
Also published as: JP2001017394A

Description

【０００１】
【発明の属する技術分野】
本発明は、眼底カメラ、更に詳細には、被検眼の角膜反射を利用して被検眼に対してアライメントを行なうことができる眼底カメラに関する。
【０００２】
【従来の技術】
眼底カメラを使用する際、眼底の観察ないし撮影を行なうためには、眼底カメラと被検眼の相対位置を調整するアライメント作業が必要である。通常アライメントは、まず被検眼前眼部と眼底力メラの位置合わせを行ない、その後、被検眼眼底と眼底カメラの位置合わせが行なわれる。そのために、先に合わせた被検眼と眼底カメラの眼軸・光軸方向から見た位置関係を維持した状態で被検眼と眼底カメラの間の距離を縮めるために眼底カメラを被検眼の方へ動かすことになる。しかしながら眼底カメラは四方八方自由に動くようになっているので、一方向の位置関係を維持しつつ、他方向の位置を合わす作業はむずかしく眼底カメラを動かしている途中で光軸がずれてしまうことが度々発生し、アライメント作業が効率よく行なえない、という問題があった。
【０００３】
【発明が解決しようとする課題】
本発明は、このような問題点を解決するためになされたもので、簡単な方法で容易にかつ確実にアライメントを行なうことができ、効率的なアライメント作業が可能な眼底カメラを提供することをその課題とする。
【０００４】
【課題を解決するための手段】
本発明では、上記課題を解決するために、アライメント光源を用いて眼底カメラと被検眼の位置合わせを行う眼底カメラにおいて、第１と第２のアライメント光源と、第１のアライメント光源の角膜反射像を被検眼の前眼部近傍に形成する手段と、第２のアライメント光源の角膜反射像を被検眼の眼底に形成する手段と、形成された第１と第２のアライメント光源の角膜反射像を観察する手段とを設け、第１のアライメント光源の角膜反射像に基づき眼底カメラと被検眼の位置合わせを行った後、第２のアライメント光源の角膜反射像により眼底カメラと被検眼の位置合わせを行う。このような構成において、請求項１の発明では、眼底カメラと被検眼の距離に応じて第１と第２のアライメント光源の点灯並びに消灯が制御される。請求項２の発明では、第１と第２のアライメント光源が点滅制御され、請求項３の発明では、請求項２の発明における第１と第２のアライメント光源の点滅速度が異なる。請求項４の発明では、第１と第２のアライメント光源の形状、色又は配置位置が異なる。請求項５の発明では、第１のアライメント光源が、被検眼前眼部を観察又は撮影するときの光源として使用される。請求項６の発明では、第１のアライメント光源は、一対の光源からなっており、被検眼の前眼部近傍に位置合わせされたとき該一対の光源による２つの角膜反射像が前眼部の中心に対して対称に並ぶように配置される。請求項７の発明では、請求項６の発明における第１と第２のアライメント光源の一方が点灯しているときは、他方が消灯される。請求項８の発明では、請求項６又７の発明における第１と第２のアライメント光源が近赤外光を発光する光源となっている。請求項９の発明では、第２のアライメント光源は、一対の光源からなっており、被検眼の眼底に位置合わせされたとき該一対の光源による２つの角膜反射像が眼底の中心に対して対称に並ぶように配置される。
【０００５】
【発明の実施の形態】
以下、図面に示す実施の形態に基づいて本発明を詳細に説明する。
【０００６】
図１には、眼底カメラの概観が図示されており、眼底カメラ本体１０は操作レバー１１とそれに付随の操作リング１１ａの操作により架台１２上を前後左右方向並びに被検者１３に対して上下方向に移動できるように構成されている。更に眼底カメラ本体は、被検眼を中心に水平面内で回動できると共に、軸１０ａを中心に垂直面内でも回動できるようになっていて、額当て１０ｂに額を当て、顎台１０ｃに顎を当てて着座する被検者１３の被検眼１３ａに対して位置合わせ（アライメント）できるようになっている。この位置合わせは、後述するように、まずアライメント光源ＬＥＤ１、２の被検眼１３ａの角膜反射による虚像を検者が観察し、操作レバー１１を操作して眼底カメラ本体１０を被検眼１３ａに対して移動させることにより行われる。
【０００７】
図２には、眼底カメラの光学系の配置が図示されており、観察用光源であるランプＬＡがミラーＭ１の中心に配置され、このランプから発せられた光は、コンデンサーレンズＬ１、可視光をカットし赤外光ないし近赤外光のみを通過させるフィルタＦ、コンデンサーレンズＬ２を経て、全反射ミラーＭ２によって反射され、続いてリレーレンズＬ３、Ｌ４を経て、中心に穴のあいた穴あき全反射ミラーＭ３で反射されてから、対物レンズＬ５を経て被検眼Ｅの瞳Ｅｐより眼底Ｅｒに入射される。
【０００８】
眼底Ｅｒからの反射光は、再び瞳Ｅｐから対物レンズＬ５を介して受光され、穴あき全反射ミラーＭ３の穴を介して合焦レンズＬ６、結像レンズＬ７を通過し、ミラーＭ４に入射する。ミラーＭ４で反射された光は、レンズＬ８を通過してミラーＭ６で反射された後レンズＬ９を介してＣＣＤ上に結像され、その像がモニタＭで観察できるように構成されている。
【０００９】
また、フォーカス検知用の光源ＬＥＤ（発光ダイオード）が設けられ、この光源からの光は、レンズＬ１０、ミラーＭ８、レンズＬ１１を経て穴あき全反射ミラーＭ３と結像レンズＬ６間に配置されたミラーＭ９に入射され、穴あき全反射ミラーＭ３、レンズＬ５を介して眼底Ｅｒに合焦用のスポット像が形成される。
【００１０】
また、眼底像を撮影するために、フィルタＦとレンズＬ２間に撮影用光源であるストロボＳＲが配置される。このとき、３５ｍｍフィルムＦ１上に眼底像を撮影する場合は、ミラーＭ４が光路から外され、眼底像がフィルムＦ１上に導かれる。またポラロイドカメラで撮影する場合には、ミラーＭ６が光路からはずされ、眼底像がポラロイドカメラのフィルムＦ２に導かれる。
【００１１】
また、近赤外光を発生するアライメント光源ＬＥＤ３とＬＥＤ４（発光ダイオード）が設けられ、その光源の像がレンズＬ２０によりオプティカルファイバーＯＦの一端面に結像される。オプティカルファイバーＯＦの他端は、穴あき全反射ミラーＭ３の中心に配置され、その像が対物レンズＬ５を介して被検眼Ｅに投影される。その場合、オプティカルファイバーＯＦの他端の角膜反射像（虚像）が被検眼Ｅの眼底Ｅｒに形成されるような光学系になっている。なお、光源ＬＥＤ３とＬＥＤ４は、図面の紙面に垂直方向に配置されているので、図２では、重なって図示されている。
【００１２】
更に、対物レンズＬ５の外周には、同様に近赤外光を発生するアライメント用の外部照明光源ＬＥＤ１とＬＥＤ２（発光ダイオード）が配置される。これらの光源の前方には被検眼Ｅの前眼部近傍と対向するように配置された絞りＳ１とＳ２が設けられており、絞りＳ１、Ｓ２からでる光源ＬＥＤ１、ＬＥＤ２の光は被検眼の角膜により反射され、その角膜反射像（虚像）が前眼部近傍に形成されるようになっている。なお、光源ＬＥＤ１とＬＥＤ２は、図２では、紙面に平行に図示されているが、通常は、ＬＥＤ３、ＬＥＤ４と同様に紙面に垂直方向に配置され、これが図３（Ａ）に正面から見た図として図示されている。
【００１３】
上述したアライメント用の光源ＬＥＤ１からＬＥＤ４は、図１に図示したように、眼底カメラ本体１０の架台１２に対する移動に応じて点灯、消灯が制御されるようになっている。図１に示した位置では、スイッチＳＷ１がスライダ１４により閉じられ、それによりＬＥＤ１とＬＥＤ２が点灯し、一方、スイッチＳＷ２は開放してＬＥＤ３とＬＥＤ４が消灯する。眼底カメラ本体１０が更に被検眼１３ａに向かって前進すると、スライダ１４も前方に移動してスイッチＳＷ１とＳＷ２の両方が閉じるようになり、それによりＬＥＤ１からＬＥＤ４が点灯し、更に前進すると、スイッチＳＷ１が開放してＬＥＤ１とＬＥＤ２が消灯し、スイッチＳＷ２が閉じてＬＥＤ３とＬＥＤ４が点灯するようになる。しかし、すべてのＬＥＤが消灯することは構造上ないように構成されている。
【００１４】
次にこのように構成された眼底カメラの動作を説明する。
【００１５】
まず、ランプＬＡが点灯しそのランプ光源の光がミラーＭ１、レンズＬ１を介してフィルタＦを通過し、レンズＬ２〜Ｌ５を介して眼底Ｅｒに投射され、眼底Ｅｒが照明される。また、眼底カメラ本体１０は架台１２に対して図１に図示した位置にあるので、スイッチＳＷ１が閉じＬＥＤ１と２が点灯する。このＬＥＤ１と２の光源の像は、角膜反射により虚像となってモニタＭに輝点となって観察される。眼底に比べて位置合わせが容易である前眼部に位置合わせを行うと、ＬＥＤ１と２の角膜反射像が、被検眼１３ａの前眼部近傍に形成されるので、図３（Ｂ）に図示したように、ＬＥＤ１と２の光源の虚像２０ａ、２０ｂが輝点として前眼部中央付近に現れる。
【００１６】
この状態で眼底カメラ本体を更に被検眼１３ａに近づけると、輝点２０ａ、２０ｂがそれぞれ外側に寄っていく状態がモニタＭで観察される（図３（Ｃ））。眼底カメラの近づける方向が光軸と一致していると、左右均等に２つの輝点２０ａ、２０ｂが動いていくので、アライメントの途中で光軸がずれても、どの方向にずれたかが把握しやすく、アライメントの修正が容易になる。
【００１７】
このように、輝点２０ａ、２０ｂが左右均等に移動するように眼底カメラ本体１０を動かせば、対前眼部から対眼底へ正しく眼底カメラ本体を移動できる。眼底カメラ本体をさらに被検眼１３ａに近づけると、これまで見えていた輝点２０ａ、２０ｂはモニタＭの画面から外に出て消えてしまうが、図３（Ｄ）に図示したように、眼底Ｅｒに形成される光源ＬＥＤ３と４の角膜反射像（虚像）が別の輝点２１ａ、２１ｂとなって左右それぞれに現れるようになる。なお、この図３（Ｃ）から（Ｄ）の状態に移行する間、スイッチＳＷ１とＳＷ２の両方が閉じ、ＬＥＤ１から４がすべて点灯するようにしておくものとする。それに対して、図３（Ｄ）から（Ｅ）の方向に移動するときは、スイッチＳＷ２のみが閉じるようにする。
【００１８】
以降は新たに現れた輝点２１ａ、２１ｂを元に眼底カメラの位置合わせを行う。輝点２１ａ、２１ｂが、図３（Ｅ）に図示したように、最も小さくなる点が最良に位置合わせされた状態となる。このようにしてアライメントを完了すると、焦点調節を行ったあとストロボＳＲを点灯し、眼底像を３５ｍｍフィルムＦ１ないしポラロイドカメラフィルムＦ２に撮影する。このとき３５ｍｍフィルムＦ１に撮影する場合は、ミラーＭ４を光路から離脱させ、一方、ポラロイドカメラフィルムＦ２に撮影する場合は、ミラーＭ４を光路に挿入してミラーＭ６を光路から離脱させる。
【００１９】
なお、ＬＥＤ１から４を点灯するとき、これらの光源を所定の周期で点滅させるようにすると、検者が各輝点を識別しやすくなる。このときＬＥＤ１と２の点滅周期をＬＥＤ３とＬＥＤ４の点滅周期と異ならしめると、どのＬＥＤが点灯しているかが識別でき操作性のよいアライメントが可能となる。また各光源の色、形状、配置を異ならしめ、輝点２０ａ、２０ｂの色、形状、配置を輝点２１ａ、２１ｂと異なるようにすることもできる。例えば、輝点２０ａ、２０ｂを赤が多めの色に、輝点２１ａ、２１ｂを赤が少なめの色にしたり、輝点２０ａ、２０ｂの形状を丸に、また輝点２１ａ、２１ｂの形状を四角にしたり、また、輝点２０ａ、２０ｂは、図３（Ｂ）、（Ｃ）に図示した方向に現れ、輝点２１ａ、２１ｂは図３（Ｄ）、（Ｅ）と直角方向に現れたりするようにすることもできる。
【００２０】
また、光源ＬＥＤ１と２を、被検眼前眼部を観察又は撮影するときの光源として使用するようにすることもできる。
【００２１】
【発明の効果】
以上説明したように、本発明では、被検眼の前眼部近傍に形成されるアライメント光源の角膜反射像を目安に、眼底カメラと被検眼の位置合わせを行った後、被検眼の眼底に形成されるアライメント光源の角膜反射像によって、眼底カメラと被検眼の位置合わせが行なわれる。このような構成により、最初は位置合わせが容易な前眼部でアライメントが行われた後、その状態を維持しながら眼底に対して位置合わせを行なうことができるので、容易でかつ確実なアライメントが可能となる。
【図面の簡単な説明】
【図１】本発明の眼底カメラの概観を示す側面図である。
【図２】眼底カメラの光学系の配置を示した配置図である。
【図３】（Ａ）は、対物レンズとアライメント光源の配置を示した配置図、（Ｂ）〜（Ｅ）はアライメント動作中にモニタに現れる画像を示した説明図である。
【符号の説明】
１０眼底カメラ本体
１１操作レバー
１２架台
ＬＥＤ１〜ＬＥＤ４アライメント光源[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a fundus camera, and more particularly, to a fundus camera that can perform alignment on a subject's eye using corneal reflection of the subject's eye.
[0002]
[Prior art]
When using the fundus camera, in order to observe or photograph the fundus, an alignment operation for adjusting the relative position between the fundus camera and the eye to be examined is necessary. In the normal alignment, the anterior eye portion of the eye to be examined and the fundus force mela are first aligned, and then the eye fundus of the eye to be examined and the fundus camera are aligned. Therefore, in order to reduce the distance between the eye to be examined and the fundus camera while maintaining the positional relationship of the eye to be examined and the eye axis / optical axis direction of the fundus camera, the fundus camera is moved toward the eye to be examined. Will move. However, the fundus camera is designed to move freely in all directions, so it is difficult to adjust the position in the other direction while maintaining the positional relationship in one direction, and the optical axis will shift while moving the fundus camera. There was a problem that the alignment work could not be performed efficiently.
[0003]
[Problems to be solved by the invention]
The present invention has been made to solve such problems, and it is an object of the present invention to provide a fundus camera that can be easily and reliably aligned by a simple method and that can perform an efficient alignment operation. Let that be the issue.
[0004]
[Means for Solving the Problems]
In the present invention , in order to solve the above problem, in a fundus camera that aligns the fundus camera and the eye to be examined using an alignment light source, the first and second alignment light sources, and a cornea reflection image of the first alignment light source , A means for forming a corneal reflection image of the second alignment light source on the fundus of the eye to be examined, and a corneal reflection image of the formed first and second alignment light sources. Means for observing, aligning the fundus camera and the eye to be examined based on the cornea reflection image of the first alignment light source, and then aligning the fundus camera and the eye to be examined by the cornea reflection image of the second alignment light source Do. In such a configuration, in the first aspect of the invention, lighting and extinguishing of the first and second alignment light sources are controlled according to the distance between the fundus camera and the eye to be examined. In the invention of claim 2, the first and second alignment light sources are controlled to blink. In the invention of claim 3, the blinking speeds of the first and second alignment light sources in the invention of claim 2 are different. In the invention of claim 4, the shape, color or arrangement position of the first and second alignment light sources are different. In the invention of claim 5, the first alignment light source is used as a light source when observing or photographing the anterior eye portion to be examined. In the invention of claim 6, the first alignment light source is composed of a pair of light sources, and two corneal reflection images of the pair of light sources when the eye is aligned in the vicinity of the anterior eye portion of the eye to be inspected. Arranged symmetrically with respect to the center. In the invention of claim 7, when one of the first and second alignment light sources in the invention of claim 6 is turned on, the other is turned off. In the invention of claim 8, the first and second alignment light sources in the invention of claim 6 or 7 are light sources that emit near-infrared light. In the invention of claim 9, the second alignment light source is composed of a pair of light sources, and two corneal reflection images by the pair of light sources are symmetrical with respect to the center of the fundus when aligned with the fundus of the eye to be examined. It is arranged to line up.
[0005]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings.
[0006]
FIG. 1 shows an overview of the fundus camera. The fundus camera main body 10 is operated on the gantry 12 in the front-rear and left-right directions and in the vertical direction with respect to the subject 13 by operating the operation lever 11 and the operation ring 11 a attached thereto. It is configured to be able to move to. Further, the fundus camera body can be rotated in the horizontal plane around the eye to be examined, and can also be rotated in the vertical plane around the axis 10a. The forehead is placed on the forehead pad 10b, and the jaw table 10c is placed on the chin. Can be positioned (aligned) with respect to the eye 13a of the subject 13 who sits on the subject. In this alignment, as will be described later, first, the examiner observes a virtual image due to corneal reflection of the eye 13a to be examined of the alignment light sources LED1 and 2, and operates the operation lever 11 to bring the fundus camera body 10 to the eye 13a to be examined. This is done by moving it.
[0007]
FIG. 2 shows the arrangement of the optical system of the fundus camera. A lamp LA, which is an observation light source, is arranged at the center of the mirror M1, and the light emitted from this lamp is converted into a condenser lens L1 and visible light. It is reflected by the total reflection mirror M2 after passing through the filter F and condenser lens L2 that cut and pass only infrared light or near infrared light, and then through the relay lenses L3 and L4, and the total reflection with a hole in the center. After being reflected by the mirror M3, the light enters the fundus Er through the pupil Ep of the eye E through the objective lens L5.
[0008]
The reflected light from the fundus Er is received again from the pupil Ep through the objective lens L5, passes through the focusing lens L6 and the imaging lens L7 through the hole of the perforated total reflection mirror M3, and enters the mirror M4. . The light reflected by the mirror M4 passes through the lens L8, is reflected by the mirror M6, then forms an image on the CCD via the lens L9, and the image can be observed on the monitor M.
[0009]
Further, a light source LED (light emitting diode) for focus detection is provided, and light from this light source passes through the lens L10, the mirror M8, and the lens L11, and is a mirror disposed between the perforated total reflection mirror M3 and the imaging lens L6. A spot image for focusing is formed on the fundus Er through the holed total reflection mirror M3 and the lens L5.
[0010]
In addition, a strobe SR, which is a light source for photographing, is disposed between the filter F and the lens L2 in order to photograph a fundus image. At this time, when photographing a fundus image on the 35 mm film F1, the mirror M4 is removed from the optical path, and the fundus image is guided onto the film F1. When photographing with a polaroid camera, the mirror M6 is removed from the optical path, and the fundus image is guided to the film F2 of the polaroid camera.
[0011]
Further, alignment light sources LED3 and LED4 (light emitting diodes) that generate near-infrared light are provided, and an image of the light source is formed on one end face of the optical fiber OF by the lens L20. The other end of the optical fiber OF is disposed at the center of the perforated total reflection mirror M3, and an image thereof is projected onto the eye E through the objective lens L5. In this case, the optical system is such that a cornea reflection image (virtual image) at the other end of the optical fiber OF is formed on the fundus Er of the eye E. In addition, since light source LED3 and LED4 are arrange | positioned in the orthogonal | vertical direction with respect to the paper surface of drawing, they are illustrated in FIG.
[0012]
Further, on the outer periphery of the objective lens L5, alignment external illumination light sources LED1 and LED2 (light emitting diodes) that similarly generate near infrared light are arranged. In front of these light sources, diaphragms S1 and S2 are provided so as to face the vicinity of the anterior eye part of the eye E, and light from the light sources LED1 and LED2 emitted from the diaphragms S1 and S2 is cornea of the eye to be examined. The corneal reflection image (virtual image) is formed in the vicinity of the anterior ocular segment. The light sources LED1 and LED2 are shown in FIG. 2 parallel to the paper surface, but are usually arranged in the direction perpendicular to the paper surface as in the case of LED3 and LED4, and this is seen from the front in FIG. It is illustrated as a figure.
[0013]
The light sources LED1 to LED4 for alignment described above are controlled to be turned on and off according to the movement of the fundus camera body 10 relative to the gantry 12 as shown in FIG. In the position shown in FIG. 1, the switch SW1 is closed by the slider 14, whereby the LEDs 1 and 2 are turned on, while the switch SW2 is opened and the LEDs 3 and 4 are turned off. When the fundus camera main body 10 further advances toward the eye 13a to be examined, the slider 14 also moves forward, so that both the switches SW1 and SW2 are closed. Is opened, LED1 and LED2 are turned off, switch SW2 is closed, and LED3 and LED4 are turned on. However, the structure is such that all the LEDs are not turned off.
[0014]
Next, the operation of the fundus camera configured as described above will be described.
[0015]
First, the lamp LA is turned on, and the light from the lamp light source passes through the filter F via the mirror M1 and the lens L1, and is projected onto the fundus Er via the lenses L2 to L5 to illuminate the fundus Er. Further, since the fundus camera body 10 is in the position shown in FIG. 1 with respect to the gantry 12, the switch SW1 is closed and the LEDs 1 and 2 are lit. The images of the light sources of the LEDs 1 and 2 become virtual images by corneal reflection and are observed as bright spots on the monitor M. When alignment is performed on the anterior eye part, which is easier to align than the fundus, a cornea reflection image of the LEDs 1 and 2 is formed in the vicinity of the anterior eye part of the eye 13a to be examined, which is illustrated in FIG. As described above, the virtual images 20a and 20b of the light sources of the LEDs 1 and 2 appear as bright spots near the center of the anterior segment.
[0016]
In this state, when the fundus camera body is further brought closer to the eye 13a to be examined, a state in which the bright spots 20a and 20b approach each other is observed on the monitor M (FIG. 3C). If the direction in which the fundus camera approaches is coincident with the optical axis, the two bright spots 20a and 20b move evenly to the left and right, so even if the optical axis is shifted during the alignment, it is easy to grasp in which direction it has shifted. Alignment correction becomes easy.
[0017]
In this way, if the retinal camera body 10 is moved so that the bright spots 20a and 20b move evenly from side to side, the retinal camera body can be correctly moved from the anterior segment to the fundus. When the fundus camera main body is further brought closer to the eye 13a to be examined, the bright spots 20a and 20b that have been seen so far go out of the screen of the monitor M and disappear, but as shown in FIG. The corneal reflection images (virtual images) of the light sources LED3 and 4 formed on the left and right sides become separate bright spots 21a and 21b and appear on the left and right respectively. It is assumed that both the switches SW1 and SW2 are closed and the LEDs 1 to 4 are all lit during the transition from the state shown in FIG. On the other hand, when moving in the direction from (D) to (E) in FIG. 3, only the switch SW2 is closed.
[0018]
Thereafter, the fundus camera is aligned based on the newly appeared bright spots 21a and 21b. As shown in FIG. 3E, the brightest points 21a and 21b are in the state where the smallest point is best aligned. When the alignment is completed in this manner, the strobe SR is turned on after performing the focus adjustment, and the fundus image is photographed on the 35 mm film F1 or the polaroid camera film F2. At this time, when photographing on the 35 mm film F1, the mirror M4 is detached from the optical path. On the other hand, when photographing on the polaroid camera film F2, the mirror M4 is inserted into the optical path and the mirror M6 is separated from the optical path.
[0019]
When the LEDs 1 to 4 are turned on, these light sources are made to blink at a predetermined cycle, so that the examiner can easily identify each bright spot. At this time, if the blinking cycle of the LEDs 1 and 2 is made different from the blinking cycle of the LED3 and LED4, it is possible to identify which LED is lit, and alignment with good operability becomes possible. Also, the color, shape and arrangement of each light source can be made different so that the colors, shapes and arrangement of the bright spots 20a and 20b are different from those of the bright spots 21a and 21b. For example, the bright spots 20a and 20b have a red color, the bright spots 21a and 21b have a red color, the bright spots 20a and 20b have a round shape, and the bright spots 21a and 21b have a square shape. In addition, the bright spots 20a and 20b appear in the direction shown in FIGS. 3B and 3C, and the bright spots 21a and 21b appear in a direction perpendicular to FIGS. 3D and 3E. It can also be done.
[0020]
In addition, the light sources LED1 and 2 can be used as light sources when observing or photographing the anterior segment of the eye to be examined.
[0021]
【The invention's effect】
As described above, in the present invention, the fundus camera and the eye to be inspected are aligned on the basis of the cornea reflection image of the alignment light source formed in the vicinity of the anterior eye portion of the eye to be examined, and then formed on the fundus of the eye to be examined. The fundus camera and the eye to be examined are aligned by the cornea reflection image of the alignment light source. With such a configuration, the alignment can be performed with respect to the fundus while maintaining the state after the alignment is first performed with the anterior segment that is easy to align, so that easy and reliable alignment is possible. It becomes possible.
[Brief description of the drawings]
FIG. 1 is a side view showing an overview of a fundus camera of the present invention.
FIG. 2 is an arrangement diagram showing an arrangement of an optical system of a fundus camera.
3A is an arrangement diagram showing the arrangement of an objective lens and an alignment light source, and FIGS. 3B to 3E are explanatory diagrams showing images appearing on a monitor during an alignment operation. FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Fundus camera body 11 Operation lever 12 Base LED1-LED4 Alignment light

Claims

In the fundus camera that aligns the fundus camera and the eye to be examined using an alignment light source,
First and second alignment light sources;
Means for forming a cornea reflection image of the first alignment light source in the vicinity of the anterior segment of the eye to be examined;
Means for forming a cornea reflection image of the second alignment light source on the fundus of the eye to be examined;
Means for observing the corneal reflection images of the formed first and second alignment light sources;
After alignment of the fundus camera and the subject's eye based on the corneal reflection image of the first alignment light source, it aligns the fundus camera and the subject's eye by the cornea reflection image of the second alignment light source,
A fundus camera that controls turning on and off of the first and second alignment light sources in accordance with the distance between the fundus camera and the eye to be examined .

In the fundus camera that aligns the fundus camera and the eye to be examined using an alignment light source ,
First and second alignment light sources ;
Means for forming a cornea reflection image of the first alignment light source in the vicinity of the anterior segment of the eye to be examined ;
Means for forming a cornea reflection image of the second alignment light source on the fundus of the eye to be examined ;
Means for observing the corneal reflection images of the formed first and second alignment light sources ;
After aligning the fundus camera and the eye to be inspected based on the cornea reflection image of the first alignment light source, aligning the fundus camera and the eye to be inspected by the cornea reflection image of the second alignment light source,
A fundus camera, wherein the first and second alignment light sources are controlled to blink .

The fundus camera according to claim 2 , wherein the blinking speeds of the first and second alignment light sources are different.

In the fundus camera that aligns the fundus camera and the eye to be examined using an alignment light source ,
First and second alignment light sources ;
Means for forming a cornea reflection image of the first alignment light source in the vicinity of the anterior segment of the eye to be examined ;
Means for forming a cornea reflection image of the second alignment light source on the fundus of the eye to be examined ;
Means for observing the corneal reflection images of the formed first and second alignment light sources ;
After aligning the fundus camera and the eye to be inspected based on the cornea reflection image of the first alignment light source, aligning the fundus camera and the eye to be inspected by the cornea reflection image of the second alignment light source ,
A fundus camera, wherein the first, second alignment light sources have different shapes, colors, or arrangement positions .

In the fundus camera that aligns the fundus camera and the eye to be examined using an alignment light source ,
First and second alignment light sources ;
Means for forming a cornea reflection image of the first alignment light source in the vicinity of the anterior segment of the eye to be examined ;
Means for forming a cornea reflection image of the second alignment light source on the fundus of the eye to be examined ;
Means for observing the corneal reflection images of the formed first and second alignment light sources ;
After aligning the fundus camera and the eye to be inspected based on the cornea reflection image of the first alignment light source, aligning the fundus camera and the eye to be inspected by the cornea reflection image of the second alignment light source ,
A fundus camera using the first alignment light source as a light source for observing or photographing the anterior ocular segment to be examined .

In the fundus camera that aligns the fundus camera and the eye to be examined using an alignment light source ,
First and second alignment light sources ;
Means for forming a cornea reflection image of the first alignment light source in the vicinity of the anterior segment of the eye to be examined ;
Means for forming a cornea reflection image of the second alignment light source on the fundus of the eye to be examined ;
Means for observing the corneal reflection images of the formed first and second alignment light sources ;
After aligning the fundus camera and the eye to be inspected based on the cornea reflection image of the first alignment light source, aligning the fundus camera and the eye to be inspected by the cornea reflection image of the second alignment light source ,
The first alignment light source includes a pair of light sources. When the first alignment light source is aligned in the vicinity of the anterior segment of the eye to be examined, two corneal reflection images of the pair of light sources are symmetrical with respect to the center of the anterior segment. A fundus camera characterized by being arranged side by side .

The fundus camera according to claim 6 , wherein when one of the first and second alignment light sources is turned on, the other is turned off.

The fundus camera according to claim 6 or 7 , wherein the first and second alignment light sources are light sources that emit near-infrared light.

In the fundus camera that aligns the fundus camera and the eye to be examined using an alignment light source ,
First and second alignment light sources ;
Means for forming a cornea reflection image of the first alignment light source in the vicinity of the anterior segment of the eye to be examined ;
Means for forming a cornea reflection image of the second alignment light source on the fundus of the eye to be examined ;
Means for observing the corneal reflection images of the formed first and second alignment light sources ;
After aligning the fundus camera and the eye to be inspected based on the cornea reflection image of the first alignment light source, aligning the fundus camera and the eye to be inspected by the cornea reflection image of the second alignment light source ,
The second alignment light source includes a pair of light sources, and is arranged so that two cornea reflection images of the pair of light sources are aligned symmetrically with respect to the center of the fundus when aligned with the fundus of the eye to be examined. A fundus camera characterized by that .