JP3577107B2 - Stereo microscope - Google Patents

Description

図５は本発明の第３の実施例を示す図で、接眼レンズの目側に左右の接眼レンズを覆う程度の直径の凹レンズＬ_ｎを配置して本発明の目的を達成するようにした実施例である。したがって、左右の接眼レンズは、その光軸が像の中心を通り互いに平行に配置されている。この実施例では、前記の凹レンズを配置することによって観察者の視野中心に向かう視線に輻輳をつけている。これにより観察者にとって融像し立体観察することが容易となる。また左右の接眼レンズの光軸が平行に配置されるため、接眼レンズどうしの干渉がなく、小型に出来る。
【００５７】
又、この実施例は光学像を直接観察するもので、図５に示すように実体顕微鏡で得られる像位置に拡散板１をおき、像より射出する光束の出射ＮＡを大にして射出瞳を大きくしている。
【００５８】
更にこの実施例では、接眼レンズの上部にのせる凹レンズの焦点距離が−６００ｍｍで、接眼レンズの視度調節範囲が−６〜２ディオプトリーの時に条件（５）を満足する。
【００５９】
この実施例も視野中心から射出する光線のうち、射出瞳内を通る光線は、観察者の眼に輻輳を持った傾きで入射し、観察者の瞳孔が接眼レンズの射出瞳内のどこにあっても観察者の視野中心に向かう視線が互いに輻輳の付く向きになっている。そのため観察者は眼幅調節にかかわらず容易に融像し立体視観察が出来る。
【００６０】
次に、この実施例で用いる凹レンズの詳細な説明を行なう。
【００６１】
下記は凹レンズＬ_ｎのデーターである。

ただし、上記データーでｒ_１，ｒ_２は夫々瞳５の側および接眼レンズ４の側の面の曲率半径、ｄ_１はレンズの肉厚、ｎ_１，ν_１は夫々レンズの屈折率およびアッベ数である。
この実施例において、接眼レンズの視度を−１ディオプトリーに固定し、凹レンズの焦点距離を−６００ｍｍとしたものは条件（６）を満足する。
【００６２】
この実施例によれば、観察者の眼が接眼レンズの射出瞳内のどこにあっても、観察者の視野中心に向かう視線は、必ず輻輳の付いた向きになる。したがって、通常の眼幅を持つすべての観察者に対して、眼幅調節，視度調節にかかわらず容易に融像出来、観察時の疲労感の少ない立体視観察が可能である。
【００６３】
図６は本発明の第４の実施例で、左右の接眼レンズの眼側に楔状部材（楔型プリズム）Ｐを配置し、接眼レンズからの射出光を左右外側へ屈折させるものである。接眼レンズは実施例１で用いたと同じであるが、左右の光軸は平行である。この実施例は、実体顕微鏡で得られた像の上に夫々拡散板１を設け、像よりの射出ＮＡを大にし、射出瞳を大きくする。
【００６４】
この実施例は、楔状部材の鋭角部の角度が１０°であり接眼レンズの視度範囲が−６〜＋２ディオプトリーのとき、条件（７）を満足する。これにより、視野中心から射出する光線のうち射出瞳内を通る光線が観察者の眼に輻輳を持つ傾きで入射し観察者の瞳孔が接眼レンズの射出瞳内のどこにあっても観察者の眼幅調節にかかわらず、容易に融像し、立体観察が可能である。
【００６５】
又上記実施例で、楔状部材の鋭角部の角度を２°として、接眼レンズの視度を−１ディオプトリーに固定したもので条件（８）を満足し得る。ここで楔状部材の材料は屈折率ｎ＝１．５１６３３でアッベ数ν＝６４．１である。これにより観察者の眼が接眼レンズの射出瞳内のどこにあっても観察者の視野中心へ向かう視線が必ず輻輳の付いた向きになる。そのため、通常の分布内の眼幅を持つすべての観察者に対して眼幅調節、視度調節にかかわらず容易に融像でき、観察時の疲労感の少ない立体視観察が可能である。
【００６６】
本発明の実体顕微鏡は、以上説明した通りで、特許請求の範囲の各請求項に記載されたもののほか、次の各項に記載したものも含まれる。
（１） 特許請求の範囲の請求項１に記載されているもので、接眼レンズの射出瞳の径が１２ｍｍ以上であることを特徴とする実体顕微鏡。
（２） 特許請求の範囲の請求項２に記載されているもので、接眼レンズの視度が−６ｍ^−１（ディオプトリー）から０ｍ^−１（ディオプトリー）のいずれかに固定されていて、この固定された視度で、下記の条件（２）を満足する実体顕微鏡。
【００６７】
２．１°＜θ’＜８．２°
ただしθ’は接眼レンズの光軸上に像の中心を配置し、左右の接眼レンズを外側に傾斜させた時の傾斜角である。
（３） 特許請求の範囲の請求項３に記載されているもので、接眼レンズの視度が−６ｍ^−１（ディオプトリー）から０ｍ^−１（ディオプトリー）のいずれかに固定され、この固定された視度において下記の条件（４）を満足することを特徴とする実体顕微鏡。
【００６８】
（４） ０．０３＜Δ’＜０．１４ｆ
ただしΔ’は接眼レンズの光軸の相対的な偏位量、ｆは接眼レンズの焦点距離である。
（４） 特許請求の範囲の請求項１に記載されているもので二つの接眼レンズの光軸が互いに平行であり、二つの接眼レンズの射出側に二つの接眼レンズを覆う凹レンズ或いは二つの接眼レンズの各々に光路を互いに鋭角部を向い合わせた模型プリズムを配置した実体顕微鏡。
【００６９】
（５） 前記（４）に記載されているもので、接眼レンズの視度が−６ｍディオプトリーから１ディオプトリーの間の値に固定され、以下の条件（６）を満足する実体顕微鏡。
（６） −７９０ｍｍ＜ｆ_ｎ ＜−２５０ｍｍ
ただし、ｆ_ｎ は前記凹レンズの焦点距離である。
【００７０】
（６） 前記（４）に記載されているもので、接眼レンズの視度が−６ｍディオプトリーから０ディオプトリーの間のいずれかの値に固定され、以下の条件（８）を満足する実体顕微鏡。
（８） ４°＜δ’＜１５°
ただし、δ’は楔状部材の鋭角部の角度である。
【００７１】
【発明の効果】
本発明の実体顕微鏡は、接眼レンズの視出射瞳径が８ｍｍ以上で二つの像の中心から発して接眼レンズを射出する二つの光束が互いに離れる方向に向かうように夫々傾斜させるようにしたもので、眼幅調節にかかわらず又観察者の僅かな頭の動きによる像のけられのない立体視観察を可能にしたものである。
【図面の簡単な説明】
【図１】本発明の実体顕微鏡の基本構成を示す図
【図２】本発明の第１の実施例の構成を示す図
【図３】本発明を用いたテレビカメラの構成を示す図
【図４】本発明の第２の実施例の構成を示す図
【図５】本発明の第３の実施例の構成を示す図
【図６】本発明の第４の実施例の構成を示す図
【図７】従来の方法による眼幅視度に対する観察者の視野中心に向かう視線との関係を示す図
【図８】上記従来の方法における左右像の融像を示す図[0001]
[Industrial applications]
The present invention relates to a stereoscopic microscope that allows an observer to perform stereoscopic observation with both eyes.
[0002]
[Prior art]
When observing an object with a stereoscopic microscope such as an operating microscope, the observer adjusts the interpupillary distance (the distance between the centers of the exit pupils of the left and right eyepieces of the microscope to the distance between the optical axes of the right and left eyes) in order to perform normal stereoscopic observation. Two operations of adjusting the diopter (operation of adjusting the diopter of the eyepiece to the eyesight of the observer) must be performed independently of each other.
[0003]
In conventional stereomicroscopes, since the exit pupil diameter of the eyepiece is very small, if the observer's head moves during observation, the image is blurred, so that the observer always keeps his head constant while performing work. It has to be placed in a position, and there is a drawback that it gives a strong fatigue to the observer, especially when the observation is for a long time.
[0004]
In order to eliminate this drawback, a diffuser is placed on the image plane viewed through the eyepiece to increase the emission NA from the image, or to increase the emission NA by using a TV monitor with a large emission NA as an image. A way to do that has been developed. If the observation is performed with a stereoscopic microscope in which the exit pupil is enlarged by such a method, the blurring of the image accompanying the movement of the head is reduced by the increase in the exit pupil, and the fatigue of the observer is reduced. .
[0005]
[Problems to be solved by the invention]
As described above, even when stereoscopic observation is performed using a stereoscopic microscope having a large exit pupil, adjustment of the interpupillary distance and diopter must still be performed.
[0006]
Also, by setting the diameter of the exit pupil to a size (8 mm or more in diameter) capable of covering variations in the human interpupillary distance (59 mm to 72 mm centering on 65 mm), even an observer having an interpupillary distance within a normal distribution. There is a method that allows any observer to observe the image without blurring. However, in this method, as shown in FIG. 7A, the eyepieces 4 and 4 are adjusted to a dioptric power to the minus side so that the observer 8 with a narrow pupil observes, or as shown in FIG. In the case where the eyepieces 4, 4 are adjusted to a positive diopter in the plus direction, and an observer with a wide interpupillary distance observes the center distance between the exit pupils of the left and right eyepieces 4, 4, all head toward the observer's visual field center The lines of sight 9, 9 are directed to the left and right outer sides. For this reason, as shown in FIG. 8, a state where the left and right visual fields of the observer do not completely match occurs, and it becomes difficult to fuse the left and right images. In FIG. 7, W indicates the interpupillary distance, Wmin indicates the case where the interpupillary distance is the smallest, and Wmax indicates the case where the interpupillary distance is the largest.
[0007]
As described above, simply enlarging the pupil cannot easily perform stereoscopic observation by fusing left and right images in all diopter adjustment ranges for all observers.
[0008]
SUMMARY OF THE INVENTION The present invention provides a stereoscopic microscope having a large exit pupil and capable of easily performing fusion and performing stereoscopic observation even when an eye is placed at any position within the range of the exit pupil.
[0009]
[Means for Solving the Problems]
The stereomicroscope according to the present invention includes an image forming means for forming two images having parallax, and an eyepiece optical system including two eyepieces for guiding light from the two images to an observer's eye. The eyepiece optical system has an exit pupil with a diameter of 8 mm or more. In the diopter range where the eyepiece is used, two light beams emitted from the respective centers of the two images and emitted through the eyepiece are observed. On the user side in a direction away from each other.
[0010]
In the stereomicroscope of the present invention, as shown in FIG. 1, light rays 3, 3 emitted from the centers 2, 2 of the left and right images 1, 1 pass through the left and right eyepieces 4, 4 and are within the exit pupils 5, 5. When the light enters the pupils of the left and right eyes 6 and 6 of the observer, the left and right rays 3 and 3 are configured to tilt each of the rays 3 and 3 so that they intersect 7 in front of the observer's eyes. is there. That is, when the observer observes the object using the stereoscopic microscope of the present invention, convergence is given to the left and right sight lines toward the center of the visual field of the observer. Here, the images 1 and 1 may be images displayed on a display surface of a monitor such as a CRT at this position in addition to the image formed by the imaging optical system.
[0011]
If the stereomicroscope is configured as described above, even in a stereomicroscope whose exit pupil diameter is larger than the variation of the human interpupillary distance, the fusion of the left and right images as described with reference to FIG. The drawbacks such as difficulty of the method can be largely eliminated. As described above, according to the stereoscopic microscope of the present invention, if the person has an interpupillary distance within a normal distribution, the left and right images are easily fused to all observers regardless of the interpupillary adjustment, and the observation is performed. Stereoscopic observation with less feeling of fatigue at the time can be performed.
[0012]
In the stereomicroscope of the present invention described above, if the diameter of the exit pupil is set to 12 mm or more, it is possible to perform an observation without adjusting the interpupillary distance and without blurring the image, and also accompanying the movement of the head during the observation. This is desirable because the image is less likely to be shaken.
[0013]
Further, in the stereomicroscope according to the present invention, the left and right eyes can be converged by tilting the optical axes of the left and right eyepieces. In this case, it is desirable to satisfy the following condition (1).
[0014]
(1) θ> tan^-1  ・ D × | a | / 2000
Where θ is the inclination angle of the left and right eyepieces to the outside of the optical axis, and D and a are the exit pupil diameter and diopter of the eyepieces, respectively.
[0015]
In the condition (1), the left side and the right side are equal to each other in the state shown in FIG. 7A in which the pupil of the observer is the innermost in the left and right exit pupils or in FIG. 7B. This is a case where the left and right sight lines toward the center of the visual field of the observer are parallel to each other, with the pupil of the observer being on the outermost side of the exit pupil. Therefore, by making the above-mentioned inclination angle θ larger than the value on the right side, the left and right sight lines toward the center of the visual field of the observer become inward, and the sight line toward the left and right visual field centers becomes congested. .
[0016]
If the above condition (1) is satisfied, the left and right images can be easily fused to all observers having the interpupillary distance within the normal distribution, regardless of the interpupillary adjustment, and even if the observer's head moves slightly. The image is not blurred, and stereoscopic observation with less feeling of fatigue during observation can be performed.
[0017]
The stereomicroscope of the present invention can be applied to a device in which the exit pupil is enlarged by using a monitor or a device in which a diffusion plate is provided at an image position to enlarge the exit pupil.
[0018]
When an observer with poor eyesight uses eyeglasses or contact lenses, the eyesight of the observer in the state corrected by the eyeglasses or contact lenses has substantially the same value regardless of the original eyesight. For this reason, there is often no problem even if the eyepiece does not have a diopter adjusting function. In consideration of this point, no problem occurs even if the diopter adjustment function is omitted from the eyepiece and the diopter of the eyepiece is fixed to an appropriate value between -6 diopters and 0 diopters. Generally, a value in the range of -2 diopters to 0 diopters is preferable, but a value in the range of -6 diopters to 0 diopters may be used. For that purpose, it is preferable to satisfy the following condition (2).
[0019]
(2) 2.1 ° <θ ′ <8.2 °
Where θ ′ is the angle of inclination of the optical axes of the left and right eyepieces outward.
[0020]
The present invention ensures that the line of sight does not point outward when looking at the center of the image, that is, the light rays emitted from the center of the image and passing through the left and right eyepieces toward the observer's eye are directed outward. To achieve that purpose. Therefore, for example, when the diopter of the eyepiece is fixed to 0 diopters, θ ′ may be slightly larger than 0 °. However, even when the diopter is 0 diopters, it is easier to observe when the line of sight is slightly inward (light rays directed toward the observer's eyes are slightly outward). Therefore, it is desirable that? 'Is actually larger than the lower limit of the above condition.
[0021]
Here, if the diopter and the pupil diameter are determined, the minimum value of the inclination angle θ can be obtained from the condition (1). Accordingly, when the minimum value of θ obtained from the condition (1) is smaller than the lower limit value of θ ′ of 2.1 ° in the condition (2), 2.1 ° which is within the range of the condition (2). If the minimum value of θ obtained by the condition (1) is larger than 2.1 °, the minimum value of θ and the condition may be selected. It is sufficient to select an appropriate value between 8.2 ° which is the upper limit of θ ′ in (2).
[0022]
If the lower limit of the condition (2) is exceeded, the drawback shown in FIG. 7 cannot be sufficiently solved for the above-mentioned reason. If the upper limit of the condition (2) is exceeded, the intersection of the line of sight toward the center of the left and right visual fields is closer to the near point 250 mm of the eye, and the difference from the focus position of the eye becomes large, making observation difficult.
[0023]
Further, in the stereomicroscope of the present invention, the left and right lines of sight can be converged by moving the optical axis of the eyepiece relative to the center of the image relatively to the left and right as shown in FIG. .
[0024]
As described above, when the optical axis of the eyepiece is moved in parallel, it is desirable that the amount of movement (the amount of eccentricity) Δ satisfies the following condition (3).
[0025]
(3) Δ> f × D × | a | / 2000
Here, f is the focal length of the eyepiece.
[0026]
The above condition (3) is a condition for increasing the amount of eccentricity so that the line of sight converging to the center of the left and right visual fields is made. By satisfying this condition (3), fusion can be easily performed for all observers having the interpupillary distance within the normal distribution irrespective of the interpupillary adjustment, and the image can be removed even if the head moves slightly. This makes it possible to perform three-dimensional observation with little fatigue at the time of observation.
[0027]
Also in this case, the present invention can be applied to a device in which the exit pupil is enlarged by using a monitor or a device in which a diffusion plate is arranged at an image position to increase the exit pupil diameter.
[0028]
In the case of the stereomicroscope of the present invention in which the optical axis of the eyepiece is moved in parallel as described above, the diopter of the eyepiece is fixed to any value between -6 diopters and 0 diopters as described above. When the operation of diopter adjustment is omitted, it is desirable to set the eccentricity Δ ′ within the range of the following condition (4).
[0029]
(4) 0.03f <Δ ′ <0.14f
If the lower limit of the condition (4) is exceeded, it will be difficult to obtain the effect for solving the problem based on FIG. 7 described above. If the upper limit is exceeded, the intersection of the line of sight toward the center of the left and right visual fields will be closer to the near point of the eye than 250 mm. And the difference between the image and the focus position of the eye becomes too large, making it difficult to see the image. Note that the same concept as the condition (2) can be applied to the lower limit. That is, when the lower limit obtained from the right side of the condition (3) is smaller than 0.03f, an appropriate value between 0.03f and 0.14f is set.Eccentric amountWhen the lower limit obtained from the condition (3) is larger than 0.03f, the value is set between 0.14f.Eccentric amountIs determined. Such a concept can be similarly applied to the upper limit of the condition (5) and the condition (6) and the lower limit of the condition (7) and the condition (8) described later.
[0030]
in this way,Eccentric amountIf Δ ′ satisfies the condition (4), all observers having the interpupillary distance within the normal distribution can be easily fused regardless of the interpupillary distance adjustment and the diopter adjustment. Even if the head moves slightly, the image is not blurred, and stereoscopic observation with less fatigue during observation is possible.
The same applies to the lower limit of the condition (8).
[0031]
The stereomicroscope of the present invention can also achieve the object by arranging a concave lens on the eye side of the eyepiece as shown in FIG. That is, by arranging a pair of right and left eyepieces with their optical axes parallel and arranging a concave lens covering them on the eye side of these eyepieces, the light rays emitted from the center of the image are refracted left and right by the concave lens, Convergence can be imparted to the line of sight of the observer toward the center of the visual field, and fusion occurs to facilitate stereoscopic observation. In this case, since the optical axes of the left and right eyepieces are parallel to each other, the eyepieces can be made compact without interference. In this stereomicroscope, it is preferable to reduce the size of the concave lens by forming the concave lens into a horizontally long shape in which a portion through which a light beam does not pass is cut.
[0032]
This stereo microscope has a focal length f of a concave lens arranged on the eye side of the eyepiece._n  Thus, the directions of refraction of the light emitted from the left and right eyepieces to the left and right sides are determined, and it is desirable to set the range of the following condition (5).
[0033]
(5) f_n  <{1000 × (D-65)} / [D × | a |]
The condition (5) is similar to the condition (1), in that the convergence is always applied to the left and right lines of sight toward the center of the visual field of the observer, regardless of where the observer's pupil is located in the enlarged exit pupil. This defines the focal length. If this condition (5) is satisfied, as in the case of condition (1), all observers having a pupil distance within a normal distribution can be easily fused regardless of pupil distance adjustment, and Even if the head moves a little, the image is not blurred, and stereoscopic observation with less fatigue at the time of observation can be performed.
[0034]
Here, when the diopter is fixed to any one of -6 diopters and 0 diopters and the diopter adjustment is omitted as described above, it is desirable that the following condition (6) is satisfied.
[0035]
(6) −790 mm <f_n  ’<-180mm
In other words, when the above condition (6) is satisfied, an appropriate convergence always occurs in the left and right eyes directed toward the center of the visual field of the observer, regardless of where the observer's pupil comes in the enlarged exit pupil.
[0036]
If the lower limit of the condition (6) is exceeded, the disadvantage described with reference to FIG. 7 will occur. If the upper limit of the condition (6) is exceeded, the intersection of the line of sight toward the center of the visual field will be closer than the near point 250 mm of the eye. The difference from the position is large, making it difficult to see.
[0037]
In addition, as shown in FIG.prismThe same effect can be obtained by arranging. In this case, it is desirable that the angle δ of the acute angle portion of the prism satisfies the following condition (7).
[0038]
(7) δ> tan^-1  [Sin ｛tan^-1(D × | a | / 2000)｝ / ｛n-cos (tan^-1  (D × | a | / 2000))｝]
Here, n is the refractive index of a wedge-shaped portion such as a prism.
[0039]
Similarly to the condition (1), the condition (7) is a condition for causing convergence in a line of sight toward the center of the visual field of the observer anywhere in the exit pupil where the pupil of the observer is enlarged. That is, when the above condition (7) is satisfied, as described above, for all observers having the interpupillary distance within the normal distribution, the image can be easily fused irrespective of the interpupillary adjustment, and the image can be moved even if the head slightly moves. It is possible to perform stereoscopic observation without shaking and with less feeling of fatigue during observation. When the wedge-shaped member (prism) is placed on the eyepiece, it is preferable that the incident surface of the prism be orthogonal to the light beam emitted from the eyepiece, since the deflection angle can be maximized. However, when the angle of the acute angle portion of the prism is small, any arrangement may be used.
[0040]
When the effects of the present invention are obtained by disposing the wedge-shaped members in this manner, the diopter of the eyepiece is set to −6 m as described above.^-10m from (-6 diopters)^-1(0 diopters), when the diopter adjustment operation is omitted, the angle δ 'of the acute angle portion of the wedge-shaped member desirably satisfies the following condition (8).
[0041]
(8) 4 ° <δ ′ <15 °
If the lower limit of the condition (8) is exceeded, the problem shown in FIG. 7 will occur. If the upper limit is exceeded, the intersection of the line of sight toward the center of the left and right visual fields will be closer than the near point 250 mm of the eye. Is too large to make it difficult to see.
[0042]
【Example】
Next, an embodiment of the stereo microscope of the present invention will be described. FIGS. 2 and 3 show the configuration of the first embodiment of the present invention. The configuration is in accordance with the basic configuration of the stereomicroscope of the present invention shown in FIG. 1 and can be easily fused.
[0043]
FIG. 3 is a diagram showing the overall configuration of the surgical microscope. This microscope includes a main body 20, two TV cameras 12, 12 mounted on the left and right sides of the microscope main body 20 via TV adapters 13, 13, and lens barrels 11, 11 mounted on an upper part of the main body. .
[0044]
In the figure, reference numeral 19 denotes an observed object. The main body 20 has a built-in objective lens 18 and left and right beam splitters disposed above the objective lens 18. Light from the object 19 is an objective lens18, A part of the beam is split by the beam splitter and enters the television adapters 13. Each of the television adapters 13, 13 has a built-in imaging lens, and receives light from a beam splitter to form two object images having parallax in the television cameras 12, 12. This image is received on a solid-state imaging device such as a CCD image sensor provided in the television cameras 12 and 12, and an output signal representing each image is obtained from each CCD. This output signal is supplied to camera control units (CCU) 15, 15 via signal lines 14, 14. The image signals that have been subjected to predetermined processing by the CCU are supplied to converters 16 and 16, converted into triple-speed RGB serial signals, and furthermore, image display devices built in the lens barrels 11 and 11 via signal lines 17 and 17. Supplied to In the figure, the image display surfaces of the display device are indicated as 1, 1 and the center positions of the respective image display surfaces are indicated by reference numerals 2, 2. This surface is the observed object image. On the image display surfaces of the lens barrels 11, 11, eyepieces 4, 4 held by vertically movable holding parts 10, 10 are arranged to form a lens barrel having an exit pupil diameter of 14 mm. Symbols 5 and 5 indicate the exit pupil position. The main body incorporates a variable-magnification optical system similar to that of an ordinary stereomicroscope, and an object image having two parallaxes is formed inside the main body by light not split by the beam splitter. Therefore, it is possible to observe an optical three-dimensional image by removing the lens barrels 11 and 11 incorporating the image display device and mounting a binocular lens barrel used for a normal stereomicroscope.
[0045]
In this example, the image display device employs a liquid crystal color filter disposed above a 1.5-inch triple-speed monochrome CRT monitor. The monitors are supplied with triple-speed RGB serial signals from the converters 16 and 16, and monochrome images corresponding to the R, G, and B signals are sequentially displayed. The liquid crystal filter operates in synchronization with the triple speed signal, and converts each monochrome image into color. In this way, by displaying RGB color images sequentially, an image with very high resolution can be obtained even though the display device is small. The horizontal size of the image display surface is 24 mm. A color liquid crystal panel or the like may be used to reduce the size of the image display device.
[0046]
FIG. 2 is a diagram showing the relationship between the display surface of the image display device and the eyepiece. In this embodiment, the optical axes of the right and left eyepieces are inclined outward by an angle θ symmetrically with respect to a parallel line formed on the two image display surfaces 1 and 1.
[0047]
In FIG. 2, when the diopter adjustment range is −6 to −4 to −2 to +2 (diopters), the inclination angle θ to the outside of the left and right eyepieces is set to 3 ° to 2 ° to 1 ° to 1 °. In this case, the value satisfies the condition (1). With this configuration, of the light rays emitted from the center of the image, the light rays that pass through the exit pupil enter the observer's eye with a convergence inclination, and where the observer's pupil is located within the exit pupil of the eyepiece. Even if there is, the line of sight toward the center of the visual field of the observer is in a direction with convergence, and the observer can easily fuse and perform stereoscopic observation regardless of diopter adjustment. In the configuration shown in FIG. 2, the diopter of the eyepiece is fixed to -1 diopter, and the optical axis of the eyepiece that intersects perpendicularly with the image center is inclined left and right outward by 2.5 °, and the condition (2) is satisfied. To be satisfied. Thus, no matter where the eye of the observer is located at the exit pupil of the eyepiece, the lines of sight toward the center of the visual field of the observer are convergent. Therefore, for all observers having the interpupillary distance within the normal distribution, fusion can be easily performed regardless of the interpupillary distance adjustment and diopter adjustment, and stereoscopic observation with less fatigue during observation can be performed. .
[0048]
FIG. 4 shows a second embodiment of the present invention in which the right and left eyepieces are decentered to obtain the effect of the present invention, and both eyepieces are moved outward by Δ as shown in the figure. In this embodiment, when the diopter adjustment range is −6 to −4 to −2 to +2 (diopters), the value of Δ is 2 mm to 1.5 mm to 1 mm to 1 mm, which satisfies the condition (3). According to this embodiment, of the rays emitted from the center of the image, rays passing through the exit pupil enter the observer's eyes with a convergence inclination, and the pupil of the observer falls within the exit pupil of the eyepiece. Regardless of where it is, the line of sight of the observer toward the center of the visual field is in a direction with convergence. Therefore, the image can be easily fused regardless of the adjustment of the eye width of the observer, and stereoscopic observation is possible.
[0049]
In this embodiment, when the diopter of the eyepiece is fixed at -1 diopter, the optical axis of the eyepiece is moved parallel to the center of the image by 1.5 mm (Δ = 1.5 mm) relatively to the left and right sides. Just do it. At this time, the value of Δ satisfies the condition (4). By doing so, the eyes directed toward the center of the visual field of the observer are in directions converging with each other, regardless of the position of the observer's eye within the exit pupil of the eyepiece. Therefore, fusion can be easily performed for all observers having the interpupillary distance within the normal distribution irrespective of the interpupillary distance adjustment and diopter adjustment, and stereoscopic observation with less fatigue during observation can be performed.
[0050]
In each of the above embodiments, the shorter the distance between the center of the image and the center of the exit pupil, the smaller the inclination of the optical axis and the amount of parallel movement of the eyepiece. As shown in FIG. 3, when a monitor image is used as an image, the smaller the inclination of the optical axis of the eyepiece and the smaller the amount of parallel movement, the more advantageous the size and simplification of the device. Therefore, it is most desirable to use a direct-view loupe type in which the center of the image and the center of the exit pupil are the shortest (observe with an eyepiece just above the monitor). It is desirable to satisfy
[0051]
(9) 20 ° ≦ ω ≦ 43.5 °
(10) 21.8 mm ≦ L_m  ≤57mm
(11) 12 mm ≦ D ≦ 31.3 mm
(12) 2.5 ≦ F_no≤6.53
(13) 3.19 ≦ β_oc≤21.8
Where ω is the viewing angle on one side of the eyepiece, L_m  Is the horizontal length of the monitor, D is the exit pupil diameter of the eyepiece, and F is_noIs the F-number of the eyepiece, β_ocIs the magnification of the eyepiece.
The lower limit of the condition (9) is an angle of view for obtaining the minimum realistic sensation necessary for the operation. If the angle is less than 20 °, the required real sensation cannot be obtained.
[0052]
The upper limit of the condition (10) is to limit the size of the monitor for arranging the monitors on the left and right while keeping the center interval of the monitors at 65 mm in consideration of the monitor frame and the like.
[0053]
The lower limit of the condition (11) is set so that the head can be moved to some extent because the distance between the human pupils is more than the variation (59 mm to 72 mm centering on 65 mm).
[0054]
In the condition (12), when the eyepiece lens has an F-number smaller than the lower limit of 2.5, it becomes difficult to perform aberration correction in design, and in order to correct aberration well, the number of lenses must be increased to increase the size. Become.
[0055]
The upper limit of the condition (9), the lower limit of the condition (10), the upper limit of the condition (11), the upper limit of the condition (12), and the condition (13) are as follows._noAnd the boundary value described above are combined.
[0056]
β_oc= (500 × tanω) / L_m
F_no= L_m/ (2 × D × tan ω)
The eyepiece data used in each of the above embodiments is as follows.

FIG. 5 shows a third embodiment of the present invention, in which a concave lens L having a diameter enough to cover the left and right eyepieces on the eye side of the eyepiece._nThis is an embodiment in which the object of the present invention is achieved by arranging. Therefore, the left and right eyepieces are arranged so that their optical axes pass through the center of the image and are parallel to each other. In this embodiment, convergence is given to the line of sight of the observer toward the center of the visual field by disposing the concave lens. Thereby, it becomes easy for the observer to perform the fusion and the three-dimensional observation. Also, since the optical axes of the left and right eyepieces are arranged in parallel, there is no interference between the eyepieces and the size can be reduced.
[0057]
In this embodiment, an optical image is directly observed. As shown in FIG. 5, the diffusion plate 1 is placed at an image position obtained by a stereo microscope, and the exit pupil is increased by increasing the exit NA of a light beam exiting from the image. I'm making it big.
[0058]
Further, in this embodiment, the condition (5) is satisfied when the focal length of the concave lens placed above the eyepiece is -600 mm and the diopter adjustment range of the eyepiece is -6 to 2 diopters.
[0059]
In this embodiment, among the rays emitted from the center of the visual field, rays passing through the exit pupil enter the observer's eyes with a convergence inclination, and the observer's pupil is located anywhere in the exit pupil of the eyepiece. Also, the line of sight toward the center of the visual field of the observer is in a direction in which convergence occurs. Therefore, the observer can easily fuse the image regardless of the interpupillary adjustment and perform stereoscopic observation.
[0060]
Next, the concave lens used in this embodiment will be described in detail.
[0061]
Below is concave lens L_nIt is the data of.

However, r₁, R₂Are the radii of curvature of the surfaces on the pupil 5 side and the eyepiece lens 4 side, respectively.₁Is the thickness of the lens, n₁, Ν₁Is the refractive index and Abbe number of the lens, respectively.
In this embodiment, the condition that the diopter of the eyepiece is fixed to -1 diopter and the focal length of the concave lens is -600 mm satisfies the condition (6).
[0062]
According to this embodiment, no matter where the observer's eye is located within the exit pupil of the eyepiece, the line of sight of the observer toward the center of the visual field is always in a direction with convergence. Therefore, for all observers having a normal interpupillary distance, fusion can be easily performed regardless of the interpupillary distance adjustment and diopter adjustment, and stereoscopic observation with less feeling of fatigue during observation is possible.
[0063]
FIG. 6 shows a fourth embodiment of the present invention, in which a wedge-shaped member (wedge-shaped prism) P is arranged on the eye side of the left and right eyepieces, and the light emitted from the eyepiece is refracted to the left and right outside. The eyepiece is the same as that used in Example 1, but the left and right optical axes are parallel. In this embodiment, a diffusion plate 1 is provided on each of the images obtained by the stereomicroscope to increase the exit NA from the image and enlarge the exit pupil.
[0064]
This embodiment satisfies the condition (7) when the angle of the acute angle portion of the wedge-shaped member is 10 ° and the diopter range of the eyepiece is −6 to +2 diopters. Thus, among rays emitted from the center of the visual field, rays passing through the exit pupil enter the observer's eye with an inclination having convergence, and the observer's pupil is located anywhere in the exit pupil of the eyepiece lens. Regardless of the width adjustment, the image can be easily fused and stereoscopic observation is possible.
[0065]
In the above embodiment, the condition (8) can be satisfied by setting the angle of the acute angle portion of the wedge-shaped member to 2 ° and fixing the diopter of the eyepiece to −1 diopter. Here, the material of the wedge-shaped member has a refractive index n = 1.51633 and an Abbe number ν = 64.1. This ensures that the line of sight toward the center of the field of view of the observer is always converged no matter where the observer's eye is within the exit pupil of the eyepiece. Therefore, fusion can be easily performed for all observers having the interpupillary distance within the normal distribution, regardless of the interpupillary distance adjustment and diopter adjustment, and stereoscopic observation with less fatigue during observation is possible.
[0066]
As described above, the stereoscopic microscope of the present invention includes not only those described in the claims but also those described in the following claims.
(1) A stereoscopic microscope according to claim 1, wherein the diameter of the exit pupil of the eyepiece is 12 mm or more.
(2) According to the second aspect of the present invention, the eyepiece has a diopter of -6 m.^-10m from (Dioptry)^-1(Diopter), and a stereomicroscope that satisfies the following condition (2) with the fixed diopter.
[0067]
2.1 ° <θ ′ <8.2 °
Here, θ ′ is the inclination angle when the center of the image is arranged on the optical axis of the eyepiece and the left and right eyepieces are inclined outward.
(3) According to claim 3 of the claims, the eyepiece has a diopter of -6 m.^-10m from (Dioptry)^-1(Diopter), wherein the fixed diopter satisfies the following condition (4).
[0068]
(4) 0.03 <Δ ′ <0.14f
Where? 'Is the relative displacement of the optical axis of the eyepiece, and f is the focal length of the eyepiece.
(4) The concave lens or the two eyepieces according to claim 1, wherein the optical axes of the two eyepieces are parallel to each other, and the two eyepieces cover the two eyepieces on the exit side of the two eyepieces. A stereomicroscope in which a model prism having an optical path facing each other at an acute angle is disposed on each of the lenses.
[0069]
(5) A stereomicroscope according to (4), wherein the diopter of the eyepiece is fixed to a value between -6 m diopters and 1 diopter, and satisfies the following condition (6).
(6) −790 mm <f_n  <-250mm
Where f_n  Is the focal length of the concave lens.
[0070]
(6) A stereomicroscope according to (4), wherein the diopter of the eyepiece is fixed to any value between -6 m diopter and 0 diopter, and satisfies the following condition (8).
(8) 4 ° <δ ′ <15 °
Here, δ 'is the angle of the acute angle portion of the wedge-shaped member.
[0071]
【The invention's effect】
In the stereomicroscope of the present invention, the eyepiece lens has a visual exit pupil diameter of 8 mm or more, and the two light beams emitted from the centers of the two images and emitted from the eyepiece lens are each inclined so as to be directed away from each other. This makes it possible to perform stereoscopic observation in which an image is not blurred due to slight head movement of the observer regardless of the interpupillary adjustment.
[Brief description of the drawings]
FIG. 1 is a diagram showing a basic configuration of a stereo microscope according to the present invention.
FIG. 2 is a diagram showing a configuration of a first exemplary embodiment of the present invention.
FIG. 3 is a diagram showing a configuration of a television camera using the present invention.
FIG. 4 is a diagram showing a configuration of a second embodiment of the present invention.
FIG. 5 is a diagram showing a configuration of a third embodiment of the present invention.
FIG. 6 is a diagram showing a configuration of a fourth embodiment of the present invention.
FIG. 7 is a diagram showing the relationship between the interpupillary diopter and the line of sight toward the center of the visual field of an observer according to a conventional method.
FIG. 8 is a diagram showing a fusion of left and right images in the conventional method.

Claims (2)

A stereomicroscope comprising: image forming means for forming two images having parallax; and an eyepiece optical system including two eyepieces for guiding light from the two images to an observer's eye, respectively. An optical system having an exit pupil having a diameter of 8 mm or more, in a diopter range in which the eyepiece is used, a direction in which two light beams emitted from the respective centers of the two images and emitted through the eyepiece are separated from each other; And the optical axes of the two eyepieces are decentered parallel to the centers of the two images, and satisfy the following condition (3).
(3) Δ> f × D × | a | / 2000
Where Δ (mm) is the amount of eccentricity of the eyepiece, f (mm) is the focal length of the eyepiece, D (mm) is the exit pupil diameter of the eyepiece, and a (1 / m) is the diopter of the eyepiece. . The diopter of the eyepiece is fixed to a value between -6 m ^-1 (diopter) and 0 m ^-1 (diopter), and the fixed diopter satisfies the following condition (4). The stereomicroscope according to claim 1, wherein:
(4) 0.03 <Δ '<0.14f
Where Δ ′ is the relative eccentricity of the optical axis of the eyepiece, and f is the focal length of the eyepiece.

Images