【発明の詳細な説明】
【０００１】
【産業上の利用分野】本発明は、眼科医院等において眼
の屈折度を測定するための眼屈折測定装置に関するもの
である。
【０００２】
【従来の技術】従来、一般的な他覚屈折装置において
は、前眼部を照明する照明光源と前眼部を撮像する撮像
手段とは、共に一体に摺動台で移動可能な構成とされ、
被検眼に対してアライメント可能とされている。
【０００３】
【発明が解決しようとする課題】本発明の目的は、筐体
に対して可動の他覚屈折計を有し、可動部を少なくした
眼屈折測定装置を提供することにある。
【０００４】
【課題を解決するための手段】上記目的を達成すための
本発明に係る眼屈折測定装置は、被検眼に対向する検眼
開口に設けた光学系部材とその周囲に設けた前眼部撮像
用の前眼部照明光源とを備えた筐体に対して、前眼部を
撮像する近赤外テレビカメラを含む他覚屈折測定計を可
動に構成し、測定の際に前記他覚屈折測定計の移動によ
り位置合わせを行うことを特徴とする。
【０００５】
【作用】上述の構成を有する眼屈折測定装置は、被検眼
の前眼部像の映像を基にして、光学部材と照明光源を備
える筐体を固定した状態で他覚眼屈折計とカメラを移動
させ、被検眼に対するアライメントを行う。
【０００６】
【実施例】本発明を図示の実施例に基づいて詳細に説明
する。図１は本発明に係る眼屈折測定装置の一実施例を
示し、被検眼Ｅに対向して可変焦点光学部材１が配置さ
れ、その後方の光軸O1上に光分割部材２、自覚検出用の
視標３が配置され、可変焦点光学部材１、光分割部材２
は筐体４に支持されている。光分割部材２の反射方向に
は、測定部５及び観察用近赤外テレビカメラ６を内蔵す
る他覚屈折計７が配置され、この他覚屈折計７は筐体４
上に移動機構８を介して載置されている。可変焦点光学
部材１は例えばシリコン等の透明な弾性物質で造られ、
その周縁を金属リング１ａで押えると曲率半径が変っ
て、焦点距離を変化できるようにされ、光分割部材２は
例えば近赤外光を反射し、可視光を透過するダイクロイ
ックミラーが用いられている。
【０００７】他覚屈折計７は移動機構８により筐体４上
を動かすことにより、アライメントを行うことができ、
かつ距離を不変に保つことができる。被検眼Ｅは可変焦
点光学部材１及び光分割部材２を通して前方の視標３を
見るようになっている。この場合に、光分割部材２及び
可変焦点光学部材１は、筐体４と一体になっていること
が必要であるが、視標３は必ずしも装置内に設置する必
要はない。更に、被検眼Ｅと可変焦点光学部材１との間
の適当な個所、例えば図示のように可変焦点光学部材１
の金属リング１ａに、テレビカメラ６用の例えば発光タ
イオード等から成る近赤外照明光源９が設けられてい
る。図２はテレビカメラ６の出力によるモニタ画面Ｓを
示し、１ｂは可変焦点光学部材１の縁部、Epは被検眼Ｅ
の瞳孔である。
【０００８】自覚検査の場合には、可変焦点光学部材１
の縁部１ｂに対して瞳孔Epがほぼ中心にくるようにアラ
イメントすればよい。このとき、図１の紙面に垂直の横
方向は可変焦点光学部材１を筐体４に対して動かし、上
下方向は筐体４自体を動かせばよい。なお、このアライ
メント精度は他覚測定と異なって光束が大きいために、
少々雑であっても実用上支障はない。
【０００９】双眼で自覚検査を行う装置では、可変焦点
光学部材１は左右にそれぞれ１個ずつ配備され、瞳孔距
離に合わせるために可変焦点光学部材１を横方向に動か
す構造となっている。自覚屈折測定は可変焦点光学部材
１の焦点距離を変えて行われ、被検眼Ｅと可変焦点光学
部材１との距離の調節は、従来のように横方向から隙間
を見てもよいが、テレビカメラ６によるモニタ画面Ｓを
見ながら額当ての位置を調節すればよい。
【００１０】他覚検査の場合の位置合わせは、テレビカ
メラ６によるモニタ画面Ｓを見ながら、他覚屈折計７を
移動機構８により筐体４上で動かし、画面Ｓ中の光軸中
心にあるマークＭが瞳孔Epの中心に至るように合わせ
る。他覚測定は小さな光束径で被検眼Ｅに投影されるた
めに、アライメント精度を高くする必要がある。このた
め、移動機構８としてはガイドレール上を動くような摺
動機構を採用すれば、アライメントを相当に精度良く行
うことができる。
【００１１】光軸O1方向の位置合わせは、自覚検査の場
合と同様に額当てを調整して顔を装置に対して動かし、
モニタ画面Ｓで瞳孔Epがぼけない位置に合わせるように
すればよい。測定部５からの近赤外光は光分割部材２、
可変焦点光学部材１を経て被検眼Ｅの眼底Erに投影さ
れ、その反射光は他覚屈折計７において光電的に処理さ
れ他覚的屈折値が得られる。
【００１２】図１の場合に、他覚測定の場合の測定部５
から光分割部材２に至る光軸O2は可変焦点光学部材１に
よる反射光を除去するために、光軸O1に対して若干傾け
てあるが、これらを合致させ、その代りに可変焦点光学
部材１を傾けるようにしても可変焦点光学部材１の反射
光を除去することができる。
【００１３】近赤外照明光源９を被検眼Ｅと可変焦点光
学部材１との間に設けると、可変焦点光学部材１の反射
がないので好都合であり、また近赤外光なので被検眼Ｅ
にとって眩しくはない。
【００１４】従来の場合は、検者は光軸O1の方向から覗
いて被検眼Ｅの中心を確認しているため、測定中は確認
できないということになるが、本実施例の場合は測定中
においても、例えば被検者が眼を細めていないかなどを
テレビカメラ６によるモニタ画面Ｓにおいて監視をする
ことができる。
【００１５】なお、可変焦点光学部材１は一例を示した
ものであり、その他に通常のように焦点距離の異なるレ
ンズを入れ換えるような構造のものを用いてもよい。
【００１６】
【発明の効果】以上説明したように本発明に係る眼屈折
測定装置は、下記に列挙する効果を有する。
（１）筐体の固定な検眼開口の位置に、検者自身が被検
眼を持ってこられるので他覚屈折計の位置合わせが容易
となる。
（２）他覚屈折計が位置合わせ時に動いても、被検眼と
の間に光学系部材があるので被検者に不安を与えず、か
つ被検眼に当接することがないので安全である。
（３）また、他覚屈折測定の位置合わせ時に他覚屈折計
が移動しても、前眼部照明光源は検眼開口の周囲に設け
られているので、その光束は検眼開口の縁により遮光さ
れることなく前眼部を照明でき、かつ光学系部材による
反射が他覚屈折計の測定を妨げることもない。Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an eye refraction measuring apparatus for measuring the refraction of an eye in an ophthalmic clinic or the like. 2. Description of the Related Art Conventionally, in a general objective refraction apparatus, an illumination light source for illuminating an anterior segment and an imaging unit for imaging the anterior segment are both movable integrally with a slide table. Configuration
Alignment is possible for the eye to be examined. SUMMARY OF THE INVENTION An object of the present invention is to provide an eye refraction measuring apparatus having an objective refractometer movable with respect to a housing and having a reduced number of movable parts. [0004] To achieve the above object, an eye refraction measuring apparatus according to the present invention comprises an optical system member provided at an optometric opening facing an eye to be examined and an anterior eye provided around the optical system member. An objective refractometer including a near-infrared television camera for imaging the anterior segment is configured to be movable with respect to a housing provided with an anterior segment illumination light source for imaging the unit, and the objective refractometer is used during measurement. The alignment is performed by moving the refractometer. The eye refraction measuring apparatus having the above-mentioned configuration is based on an image of an anterior segment of an eye to be examined, and an objective refractometer in which a housing provided with an optical member and an illumination light source is fixed. And the camera are moved to perform alignment with the eye to be examined. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail with reference to the illustrated embodiments. FIG. 1 shows an embodiment of an eye refraction measuring apparatus according to the present invention, in which a variable focus optical member 1 is disposed so as to face an eye E to be inspected, and a light splitting member 2 on an optical axis O1 behind the variable focus optical member 1. The variable target optical member 1, the light splitting member 2
Are supported by the housing 4. In the reflection direction of the light splitting member 2, an objective refractometer 7 having a built-in measuring unit 5 and an observation near-infrared television camera 6 is arranged.
It is mounted on a moving mechanism 8 above. The variable focus optical member 1 is made of a transparent elastic material such as silicon, for example.
When the peripheral edge is pressed by the metal ring 1a, the radius of curvature changes, so that the focal length can be changed. As the light splitting member 2, for example, a dichroic mirror that reflects near-infrared light and transmits visible light is used. . The objective refractometer 7 can be aligned by moving the moving mechanism 8 on the housing 4.
And the distance can be kept constant. The subject's eye E looks at the front target 3 through the variable focus optical member 1 and the light splitting member 2. In this case, the light splitting member 2 and the variable focus optical member 1 need to be integrated with the housing 4, but the optotype 3 does not necessarily need to be installed in the apparatus. Further, an appropriate portion between the eye E to be inspected and the variable focus optical member 1, for example, as shown in FIG.
The metal ring 1a is provided with a near-infrared illuminating light source 9 for the TV camera 6, which is composed of, for example, a light emitting diode. FIG. 2 shows a monitor screen S based on the output of the television camera 6, 1b is an edge of the variable focus optical member 1, and Ep is an eye E to be inspected.
Pupil. In the case of a subjective test, the variable focus optical member 1
May be aligned so that the pupil Ep is substantially at the center with respect to the edge portion 1b. At this time, the variable focus optical member 1 may be moved with respect to the housing 4 in the horizontal direction perpendicular to the paper surface of FIG. 1, and the housing 4 itself may be moved in the vertical direction. In addition, this alignment accuracy differs from objective measurement because the luminous flux is large.
There is no practical problem even if it is a little rough. In an apparatus for performing a subjective test with a binocular, one variable focus optical member 1 is provided on each of the left and right sides, and the variable focus optical member 1 is configured to move in the horizontal direction in order to match the pupil distance. The subjective refraction measurement is performed by changing the focal length of the varifocal optical member 1, and the distance between the subject's eye E and the varifocal optical member 1 can be adjusted by observing the gap from the lateral direction as in the related art. The position of the forehead contact may be adjusted while viewing the monitor screen S of the camera 6. The alignment in the case of the objective inspection is performed by moving the objective refractometer 7 on the housing 4 by the moving mechanism 8 while watching the monitor screen S by the television camera 6, and is located at the center of the optical axis in the screen S. The mark M is adjusted to reach the center of the pupil Ep. Since the objective measurement is projected onto the eye E with a small light beam diameter, it is necessary to increase the alignment accuracy. Therefore, if a sliding mechanism that moves on a guide rail is adopted as the moving mechanism 8, alignment can be performed with considerably high accuracy. The alignment in the direction of the optical axis O1 is performed by adjusting the forehead rest and moving the face relative to the apparatus in the same manner as in the subjective test.
The pupil Ep may be adjusted to a position where the pupil Ep is not blurred on the monitor screen S. The near-infrared light from the measuring unit 5 is split into the light splitting member 2,
The reflected light is projected onto the fundus Er of the eye E via the variable focus optical member 1, and the reflected light is photoelectrically processed in the objective refractometer 7 to obtain an objective refraction value. In the case of FIG. 1, a measuring unit 5 for objective measurement
The optical axis O2 extending from the optical splitting member 2 to the light splitting member 2 is slightly inclined with respect to the optical axis O1 in order to remove the reflected light from the variable focus optical member 1, but these are matched, and instead, the variable focus optical member 1 is replaced. The reflected light of the varifocal optical member 1 can be removed even if the angle is inclined. When the near-infrared illumination light source 9 is provided between the eye E to be inspected and the variable focus optical member 1, it is convenient because there is no reflection of the variable focus optical member 1, and because the near infrared light is used, the eye E
Not dazzling to. In the conventional case, since the examiner is looking in the direction of the optical axis O1 to confirm the center of the eye E, it cannot be confirmed during the measurement. In, for example, it is possible to monitor on the monitor screen S by the television camera 6 whether or not the subject has narrowed his eyes. The variable focal length optical member 1 is an example, and a variable focal length optical member having a structure in which lenses having different focal lengths are exchanged as usual may be used. As described above, the eye refraction measuring apparatus according to the present invention has the following effects. (1) Since the examiner can bring his / her eye to be examined to the position of the fixed optometry opening of the housing, the alignment of the objective refractometer becomes easy. (2) Even if the objective refractometer moves at the time of positioning, the optical system member is provided between the objective refractometer and the subject, so that the subject is not anxious and does not come into contact with the subject's eye, which is safe. (3) Even if the objective refractometer moves during the alignment of the objective refraction measurement, since the anterior segment illumination light source is provided around the optometry opening, its light beam is blocked by the edge of the optometry opening. The anterior ocular segment can be illuminated without any trouble, and the reflection by the optical system member does not disturb the measurement by the objective refractometer.
【図面の簡単な説明】
【図１】光学的構成図である。
【図２】テレビカメラの出力によるモニタ画面の正面図
である。
【符号の説明】
１ 可変焦点光学部材
１ａ 金属リング
１ｂ 縁部
２ 光分割部材
３ 視標
４ 筐体
５ 測定部
６ テレビカメラ
７ 他覚屈折計
８ 移動機構
９ 照明光源BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an optical configuration diagram. FIG. 2 is a front view of a monitor screen output from a television camera. [Description of Signs] 1 Variable focus optical member 1a Metal ring 1b Edge 2 Light splitting member 3 Optotype 4 Housing 5 Measurement unit 6 TV camera 7 Objective refractometer 8 Moving mechanism 9 Illumination light source