JP2019092725A - Front-end lens device and ophthalmic microscope - Google Patents

Abstract

An object of the present invention is to develop a front lens device in which at least two front lenses can be interchanged. The present invention relates to an engagement portion (8) that can be attached to the periphery of a lens barrel (14) of an ophthalmic microscope, and to the engagement portion (8) so as to be rotatable, and independently. A plurality of movable front lens support units; and a plurality of front lens units (601, 602, 603) held by the front lens support unit, wherein the front lens support unit includes the engagement unit. And arm portions (911, 921, 912, 922, 913, and 923) that are pivotably connected to each other, and a front lens support frame (931, 932, 933) that is connected to the arms. A front lens device (1) is provided. [Selection] Figure 1

Description

The present invention relates to an ophthalmic microscope for magnifying and observing an eye to be examined, and a pre-lens apparatus for inserting and removing a pre-lens between an objective lens of the ophthalmic microscope and the eye to be examined.
The invention relates in particular to a front lens arrangement with a mechanism by which two or more front lenses can be interchanged, and to an ophthalmic microscope having such a front lens arrangement.

An ophthalmologic microscope is a medical or examination instrument capable of magnifying and observing a subject's eye to be examined by an observation optical system including a lens or the like.
Some ophthalmologic microscopes have a function of observing an anterior segment (for example, cornea, anterior capsule, sclera etc.) and a function for observing a posterior segment (for example, retina). In this type of ophthalmic microscope, the anterior lens can be inserted into and removed from the optical path of the observation optical system between the objective lens and the subject's eye to switch between anterior segment observation and posterior segment observation.

In the anterior segment observation, as shown in FIG. 10A, the anterior segment of the subject eye 11 is positioned at the focal point position (front focal point position) U0 closer to the subject eye 11 than the objective lens 13 of the observation optical system. Thus, the distance H2 between the objective lens 13 and the eye 11 to be examined is set. Assuming that the focal distance from the objective lens 13 of the observation optical system is F1, H2 = F1.
On the other hand, when observing the back eye part, as shown in FIG. 10B, the distance H2 'between the objective lens 13 and the eye 11 to be examined is set longer, and between the front focal position U0 and the eye 11 to be examined. The front lens 6 is placed. The front lens 6 guides the light of the observation optical system as parallel light to the lens 11b of the eye to be examined, and is arranged to focus on the retina 11a through the lens 11b. Assuming that the focal length of the front lens 6 is F2, typically, H2 '≒ F1 + 2 × F2.

Various types of pre-lens devices have been developed as pre-lens devices that support the pre-lens in the optical path in a removable manner.
For example, there is provided a pre-lens system capable of inserting and removing the pre-lens in the light path of the observation optical system by holding the pre-lens by the holding arm and pivoting the holding arm about the pivot axis. It is developed (patent documents 1 [0027]-[0032]). The holding arm can further be provided with a loupe holding mechanism, and the loupe can be inserted into and removed from the optical path of the observation optical system to adjust the focal position in the eye to be examined (Patent Documents 1 [0071] to [0077] ).
In addition, a head of a revolver system in which two head lenses are attached via a lens holder bent to a lens receiving portion that rotates about a rotation axis tilted with respect to the optical axis of the observation optical system of the ophthalmic microscope Lens devices have been developed. This front lens device can switch two front lenses on the light path of the observation optical system (Patent Document 2 [0120]).

  Thus, in the conventional pre-lens apparatus, the number of pre-lenses held is usually one, at most two, and in order to use pre-lenses having different refractive powers, the pre-lenses are manually operated. It was something that needed to be replaced.

Japanese Patent Application Laid-Open No. 2003-062003 JP, 2009-205156, A

When using an ophthalmic microscope for surgery, it is common to use at least two types of front lenses. Conventionally, two types of front lenses are complicated because they require manual replacement by an assistant or the like, and development of a front lens device that can easily replace front lenses has been desired.
However, when using an ophthalmologic microscope for surgery, not only the surgeon but also the assistant etc. jointly perform the surgery on the patient's eye, the doctor and the assistant working in the vicinity of the eye contact the hands of the assistant etc. There is a problem that two types of front lenses have to be arranged so that they do not enter and do not enter the viewing field of the ophthalmic microscope.

  Therefore, in the present invention, in view of the above-mentioned conventional situation, at least two types of front lenses can be interchanged, and the operator does not come in the field of vision of the ophthalmologic microscope without the hands of the surgeon, assistant and the like coming in contact. And aims to develop a pre-lens device.

  In order to solve the above-mentioned problems, the inventors of the present application have intensively studied, and as a result, by using a front lens apparatus having at least two front lens supports having specific structures movable independently of each other. However, the inventors have found that it is possible to replace the pre-lens while preventing contact with the hands of a surgeon, an assistant, etc. or from entering the field of view of the ophthalmic microscope, and the present invention has been completed.

That is, the present invention provides the following first invention regarding the pre-lens apparatus and the following second invention regarding the ophthalmic microscope.
(1) A first aspect of the present invention relates to a front end lens apparatus for use in an ophthalmic microscope having an observation optical system for observing an eye to be examined.
An engagement portion that can be mounted around the barrel of the ophthalmic microscope;
At least two front lens supports pivotally connected to the engagement portion and movable independently;
And a front lens held on each of the front lens supports;
The front lens support portion includes an arm portion rotatably connected to the engagement portion, and a front lens support frame connected to the arm portion,
The front lens is held by the front lens support frame,
The present invention relates to a front lens apparatus characterized in that the front lens support is pivoted to insert and remove the front lens into the optical path of the observation optical system.
(2) In the front lens apparatus according to the first aspect of the invention, the arm unit is rotatably connected to the first arm, which is rotatably connected to the engagement portion, and to the first arm. It has 2 arms and
Preferably, the front lens support frame is rotatably connected to the second arm.
(3) In any one of the front lens apparatuses, it is preferable that the length of the arm portion differs depending on the focal length of the front lens.
(4) A second invention relates to an ophthalmic microscope having an observation optical system for observing an eye to be examined, the ophthalmic microscope having any of the above-mentioned front lens devices.
(5) In the ophthalmic microscope according to the second aspect of the present invention, the microscope can be inserted into and removed from the optical axis of the observation optical system, and is used to adjust the focal position closer to the eye to be examined than the objective lens of the observation optical system. It is preferable to have an objective auxiliary lens.
(6) In the ophthalmic microscope of (5), the objective auxiliary lens is preferably a lens having a negative power.
(7) In the ophthalmic microscope of (5) or (6), it is preferable to have a switching mechanism for inserting or removing the objective auxiliary lens in conjunction with insertion or removal of the front lens.
(8) In the ophthalmic microscope of (5) to (7), it is preferable to have at least n objective auxiliary lenses when the number of the front lenses is n (n 2 2) .

  According to the present invention, at least two front lens supports that are independently movable hold the front lens respectively, and the front lens support can be pivoted to the engaging portion attached to the lens barrel. And the front lens support frame connected to the arm portion, so that the front lens support is pivoted to insert and remove the front lens on the optical path of the observation optical system. Can. This makes it possible to retract the front lens to a position away from the optical path of the subject's eye and the observation optical system, and for ophthalmic use without touching hands such as a surgeon and assistant working near the subject's eye At least two types of front lenses can be arranged interchangeably so that they do not fall within the viewing field of the microscope.

It is drawing which shows typically the front lens apparatus and ophthalmic microscope of 1st Embodiment of this invention. It is a schematic diagram which shows the relationship of the distance of an objective lens and a to-be-tested eye when inserting and removing a front lens and switching an anterior ocular segment observation and a posterior ocular segment observation. FIG. 2 (A) shows the positional relationship when performing anterior segment observation, FIG. 2 (B) shows the positional relationship when performing posterior segment observation, and FIG. 2 (C) is the objective auxiliary lens Show the positional relationship when performing anterior segment observation using. It is a schematic diagram which shows the relationship of the distance of an objective lens and a to-be-tested eye in, when the refractive power of a front lens differs. FIG. 3 (A) shows the positional relationship in the case of using a front lens having a refractive power of D, and FIG. 3 (B) shows the positional relationship in the case of using a front lens having a refractive power of D ′ ′. FIG. 3C shows the positional relationship in the case of using a front lens with an optical power of D ′ ′ and an objective auxiliary lens. The ophthalmic microscope of the 2nd Embodiment of this invention WHEREIN: It is a side view which shows typically the structure of the optical system at the time of observing an anterior segment. The ophthalmic microscope of the 2nd Embodiment of this invention WHEREIN: It is a front view which shows typically the structure of the optical system at the time of observing an anterior segment. It is a perspective view which shows typically arrangement | positioning of the objective auxiliary lens at the time of observing an anterior segment. FIG. 6 (A) shows the arrangement of the objective auxiliary lens in the ophthalmic microscope of the second embodiment of the present invention, and FIG. 6 (B) shows the objective auxiliary lens on the opposite side to the eye side of the objective lens. It shows the arrangement when it is provided. The ophthalmic microscope of the 2nd Embodiment of this invention WHEREIN: It is a side view which shows typically the structure of the optical system at the time of observing a back eye part. The ophthalmic microscope of the 2nd Embodiment of this invention WHEREIN: It is a front view which shows typically the structure of the optical system at the time of observing a back eye part. It is a perspective view which shows typically arrangement | positioning of the objective auxiliary lens at the time of observing a back eye part. FIG. 9 (A) shows the arrangement of the objective auxiliary lens in the ophthalmic microscope of the second embodiment of the present invention, and FIG. 9 (B) shows the objective auxiliary lens on the opposite side of the objective eye to the eye It shows the arrangement when it is provided. It is a schematic diagram which shows the relationship of the distance of an objective lens and a to-be-tested eye when inserting and removing a front lens and switching an anterior ocular segment observation and a posterior ocular segment observation.

1. Pre-lens apparatus The pre-lens apparatus of the present invention relates to a pre-lens apparatus used in an ophthalmic microscope for observing an eye to be examined.
An engagement portion that can be mounted around the barrel of the ophthalmic microscope;
At least two front lens supports pivotally connected to the engagement portion and movable independently;
And a front lens held by the front lens support;
The front lens support portion includes an arm portion rotatably connected to the engagement portion, and a front lens support frame connected to the arm portion,
The front lens is held by the front lens support frame,
The front lens support may be pivoted to insert and remove the front lens into the light path of the observation optical system.

The front lens apparatus of the present invention has an engagement portion that can be mounted around the barrel of the ophthalmic microscope, so that it can be easily mounted on the ophthalmic microscope.
The engaging portion is connected to at least two front lens supports that are independently movable, and the front lens support can hold at least two front lenses for holding the front lens. .
And since the front lens support has the arm portion rotatably connected with the engaging portion and the front lens support frame connected with the arm, the front lens support is pivoted. , Can move the front lens. By means of such a mechanism of the front lens support, the front lens can be inserted into the optical path of the observation optical system and can be released.

The "engagement part" used in the front lens apparatus of the present invention may be of any structure as long as it has a structure that can be attached around the lens barrel of an ophthalmic microscope, for example, limited thereto Although not necessarily, it can be a ring-shaped engaging portion that can be fitted around the barrel, and if the barrel is cylindrical, it fits around the barrel Alternatively, the engaging portion may have a curved shape whose cross section is a circular arc.
In the present invention, the “lens barrel” of the ophthalmologic microscope refers to a housing having the optical element of the observation optical system inside.

One or more engaging portions may be attached around the barrel of the ophthalmic microscope. Also, although two or more front lens supports can be connected to one engaging part, one front lens support may be connected to two or more engaging parts.
The number of front lens supports is preferably 2 to 9, and more preferably 3 to 6.

In the present invention, the “arm portion” is present between the engaging portion and the front lens support frame, and has a length and a structure that allows the front lens to be inserted into the optical path of the observation optical system. Anything may be used. The arm portion may be composed of a plurality of parts and may have one or more joint portions.
The arm portion has a first arm pivotally coupled to the engaging portion, and a second arm pivotally coupled to the first arm, and the front lens support frame It is preferable that the two arms are rotatably connected. With such a structure, the arm portion can be compactly compacted when the front lens is retracted, and when the front lens is inserted into the light path of the observation optical system, the front lens The position of can be adjusted.

In the front lens device of the present invention, it is preferable that the lengths of the arm portions be different depending on the focal length of the front lens.
Thus, when the front lens is inserted into the light path of the observation optical system, the distance between the front lens and the objective lens can be made optically appropriate according to the focal length of the front lens.
Hereinafter, an example of an embodiment of the present invention will be described in detail with reference to the drawings.

First Embodiment
FIG. 1 is a view schematically showing a front lens apparatus and an ophthalmic microscope in the case of three front lenses of a first embodiment of the present invention.
As shown in FIG. 1, the front lens device 1 has an engaging portion 8 that can be attached to the lens barrel 14 of the ophthalmic microscope 2. Three front lens support portions are rotatably connected to the engagement portion 8 and each hold the front lens. The front lens 601 is held by a front lens support (911, 921, 931). The front lens support portion includes a first arm 911 pivotally connected to the engaging portion 8, a second arm 921 pivotally connected to the first arm 911, and a second arm. It has a front lens support frame 931 rotatably connected. The front lens 601 is fitted in the front lens support frame 931.
The first arm 911, the second arm 921, and the front lens support frame 931 can be rotated in the diameter direction of the lens barrel 14, so that by rotating the front lens support, the front lens 601 can be mirrored. It can be moved in the diameter direction of the cylinder 14 and inserted into the light path of the observation optical system.

The lengths of the first arm 911 and the second arm 921 are such that when the front lens 601 is inserted in the optical path of the observation optical system, the distance to the objective lens 13 becomes an optically suitable distance. It is set.
However, since the front lens support (911, 921 and 931) is rotatably connected to the engagement portion 8 and has two rotatable connection portions also in the front lens support, the front lens The stationary lens 601 can be moved up and down in the direction of the optical axis O-300 of the observation optical system, and the distance between the head lens 601 and the eye 11 can be adjusted.

  The front lens 602 is held by a front lens support (912, 922, 932). As shown in FIG. 1, by folding the first arm 912 and the second arm 922, the unused front lens 602 can be retracted around the lens barrel 14.

The front lens 603 is also held by the front lens support (913, 923, 933), and the front lens 603 is mounted on the lens barrel 14 by folding the first arm 913 and the second arm 923. Are evacuated around the
As described above, according to the front lens apparatus of the first embodiment, the front lens not in use can be retracted to a position completely away from the optical path of the eye or observation optical system. It is also possible to completely eliminate the possibility of the stationary lens coming in contact with the hands of a surgeon and an assistant working near the eye to be examined and from entering into the observation field of view of the ophthalmic microscope.

  Although the front lens support can be pivoted manually, an actuator (not shown) pivots the engagement portion and the first arm, pivots the first arm and the second arm, and It is also possible to pivot by automatically controlling the pivoting of the two arms and the front lens support frame.

The front lens 601 is a convex lens having a refractive power of 40 D, the front lens 602 is a convex lens having a refractive power of 80 D, and the front lens 603 is a convex lens having a refractive power of 120 D.
For example, if the surgeon observes the inside of the subject's eye with the ophthalmic microscope 2 using the front lens 601 having a refractive power of 40 D, and the image inside the subject's inside of the subject becomes blurred due to infocus. The stationary lens can be replaced. The surgeon uses a foot switch (not shown) to drive the actuator to pivot the front lens support, thereby inserting the front lens inserted into the optical path of the observation optical system into a front lens 602 having a refractive power of 80D. Alternatively, it can be replaced by a pre-lens 603 whose refractive power is 120D. Thus, the surgeon can easily and quickly replace the front lens without using the power of an assistant or the like, and the operability of the operation can be improved.

In the pre-lens apparatus of the present invention, the lengths of the arms may be different for at least three pre-lens supports. Thereby, when the front lens is inserted into the light path of the observation optical system, the distances between the objective lens and the front lens can be made different from each other.
As described above, since the front lenses have different refractive powers, their focal lengths are also different. The focal length can be determined as the reciprocal of the refractive power (diopter). For example, the refractive power of a 40 D front lens is 1/40 = 0.025 m and the 80 D refractive power of the front lens The refractive power is 1/80 = 0.0125 m, and the larger the refractive power, the shorter the focal length.
Therefore, it is preferable to set the length of the arm so that the distance to the objective lens when inserted into the light path of the observation optical system differs according to the focal length of the front lens.
In particular, for at least three front lenses, the length of the arm portion is set so that the position in the optical axis direction of the observation optical system is shifted by the difference in the focal length of the front lenses and inserted. Is preferred.

  According to the pre-lens apparatus of the first embodiment, the objective lens and the at least three pre-lens supports are made different by making the lengths of the first arm and / or the second arm different from each other. The distances between the front lenses can be different. Also, even if the lengths of the first arm and / or the second arm are respectively made the same, the engaging portion and the first arm when the front lens is inserted on the optical axis of the observation optical system The objective lens by making the angle with the first arm, the angle between the first arm and the second arm, and the angle between the second arm with the front lens support frame different for each front lens support. It is also possible to make the distances between the lens and the front lens different.

  In the front lens apparatus of the first embodiment, among the front lenses 601, 602, and 603, since the front lens 601 has the smallest refractive power, the focal length is the longest. Therefore, in the front lens 601, the first arm 911 and the second arm 921 are short so that the distance to the subject eye 11 is close to the focal length of the front lens 601. On the other hand, the front lens 603 has the shortest focal length because it has the largest refractive power. Therefore, in the front lens 603, the first arm 913 and the second arm 923 are long so that the distance to the subject eye 11 is close to the focal length of the front lens 603. The length of the first arm 912 and the second arm 922 is set so that the front lens 602 is intermediate between the two.

For this reason, even when the respective front lens supports are moved and the front lenses are replaced, the distance between the front lens and the eye to be examined can be maintained close to the focal length of the front lens. The position adjustment of the front lens only requires fine adjustment.
The fine adjustment of the position of the front lens is performed by the angle between the engaging portion and the first arm, the angle between the first arm and the second arm, and the angle between the second arm and the front lens support frame. It can be done by controlling.

2. Ophthalmic Microscope The ophthalmic microscope of the present invention is an ophthalmic microscope having an observation optical system for observing an eye to be examined, and in addition to the ophthalmic microscope main body, the above-mentioned 1. It has the pre-lens apparatus described in these.
In the present invention, the term "ophthalmic microscope" refers to a medical or examination instrument having an observation optical system including an optical element capable of magnifying and observing an eye to be examined, not only for humans but also for animals. Including the The “ophthalmic microscope” includes, but is not limited to, for example, a fundus camera, a slit lamp, a microscope for ophthalmologic surgery, and the like.

The ophthalmic microscope preferably further includes an illumination optical system, and the return light reflected / scattered from the eye illuminated by the illumination optical system can be magnified and observed by the observation optical system. The illumination optical system is configured to include an optical element for illuminating the subject's eye. The illumination optical system may further include a light source, but may also guide natural light to the eye to be examined.
The “observation optical system” in the present invention can be configured to be divided into a left-eye observation optical system and a right-eye observation optical system, and when parallax is generated in the images obtained by the left and right observation optical systems. Can also be observed stereoscopically by binocular vision.
The “observation optical system” in the present invention may be one in which the observer can directly observe the eye to be examined through an eyepiece lens or the like, or can be observed by receiving light with an imaging device or the like to form an image Alternatively, it may have both functions.

An objective lens is provided on the most eye side of the observation optical system. And, the pre-lens apparatus of the present invention is an apparatus capable of interchangeably inserting and removing at least two pre-lenses between an objective lens and an eye to be examined.
The pre-lens arrangement can be attached to the barrel of the ophthalmic microscope body by means of an engagement part.

As described above, the ophthalmic microscope inserts the front lens into the light path of the observation optical system between the objective lens and the eye to be examined and observes the anterior segment (eg, cornea, anterior capsule, sclera, etc.); It is possible to switch between observation of the posterior segment (for example, the retina).
FIG. 2 is a schematic view showing the relationship between the distance between the objective lens and the eye to be examined when the anterior segment observation and the posterior segment observation are switched by inserting and removing the front lens.
In the anterior segment observation, as shown in FIG. 2A, the anterior segment of the subject eye 11 is located at the focal position (front focal point position) U0 that is closer to the subject eye 11 than the objective lens 13 of the observation optical system. The distance H2 between the objective lens 13 and the eye 11 to be examined is set so as to be positioned. Assuming that the focal distance from the objective lens 13 of the observation optical system is F1, H2 = F1.
On the other hand, at the time of the posterior eye observation, as shown in FIG. 2B, the distance H2 'between the objective lens 13 and the eye 11 to be examined is set longer, and between the front focal position U0 and the eye 11 to be examined. The front lens 6 is placed. The front lens 6 guides the light of the observation optical system as parallel light to the lens 11b of the eye to be examined, and is arranged to focus on the retina 11a through the lens 11b. Assuming that the focal length of the front lens 6 is F2, typically, H2 '≒ F1 + 2 × F2.

As apparent from comparison between the distance H2 between the objective lens 13 and the eye 11 in FIG. 2A and the distance H2 ′ between the objective lens 13 and the eye 11 in FIG. 2B, In the case of inserting 6, it is necessary to increase the distance between the objective lens 13 and the eye 11 to be examined, and the ophthalmic microscope main body is moved up and down along the optical axis each time the front lens is inserted and removed. You need to Although the vertical movement of the ophthalmic microscope body can be performed manually or automatically, it is complicated to perform the movement every time the front lens is inserted and removed.
Therefore, when performing anterior segment observation, as shown in FIG. 2C, the focal length is obtained by separating the front lens from the optical path and inserting the objective auxiliary lens 17 formed of a concave lens in the optical path. To match H2 '. Then, when performing the posterior eye observation, as shown in FIG. 2B, the objective auxiliary lens 17 is separated from the light path, and the front lens 6 is inserted into the light path. By using the objective auxiliary lens 17 in this manner, the distance between the objective lens 13 and the eye 11 to be examined becomes H2 'in any of the anterior eye observation and the posterior eye observation, and the ophthalmic microscope main body is vertically There is no need to move to

Therefore, in the ophthalmic microscope of the present invention, it is preferable to have an objective auxiliary lens used to adjust the focal position on the side of the eye to be examined rather than the objective lens of the observation optical system.
Here, the objective auxiliary lens is preferably a lens having negative power capable of increasing the focal length. A lens having negative power is usually a lens also called a concave lens.
Moreover, in the ophthalmic microscope of the present invention, it is preferable to have a switching mechanism capable of automatically inserting or removing the objective auxiliary lens in conjunction with insertion or removal of the front lens.

FIG. 3 is a schematic view showing the relationship between the distance between the objective lens and the eye to be examined when the refractive powers of the front lens are different.
FIG. 3A is a view showing a state in which the front lens 6 is inserted in the optical path for the rear eye observation, and has the same positional relationship as FIG. 2B. In FIG. 3A, the distance between the objective lens 13 and the front lens 6 is indicated by H1 '. The refractive power of the front lens 6 is D.
On the other hand, FIG. 3B shows a state in which the front lens 6 is replaced with a front lens 6 ′ ′ having a larger refractive power in the same rear eye observation. The refractive power of the front lens 6 '' is D ''.

Since the focal length of the front lens 6, 6 ′ ′ is a length that can be obtained from the reciprocal of the refractive power of the lens, the focal length F2 of the front lens 6 in FIG. The focal length F2 ′ ′ of the front lens 6 ′ ′ in B) is shorter. As is clear from a comparison between FIG. 3A and FIG. 3B, the distances H1 ′ and H1 ′ ′ between the objective lens 13 and the front lenses 6 and 6 ′ ′ have short focal lengths (refractive In the case of FIG. 3 (B) using the front lens 6 '' having a large power, it is necessary to make the length shorter than the case of FIG. 3 (A). Further, the distances H2 'and H2''between the objective lens 13 and the eye 11 to be examined are also better in the case of FIG. 3 (B) using a front lens 6''having a short focal length (large refractive power) It is necessary to make it shorter than the case of FIG. 3 (A).
Therefore, when replacing the front lens, it is necessary to adjust the distance between the objective lens and the front lens, and at the same time, move the ophthalmic microscope body up and down to move between the objective lens and the eye to be examined. You also need to adjust the distance of

Therefore, when the front lens is replaced, as shown in FIG. 3C, the focal length is increased by inserting the objective auxiliary lens 17 consisting of a concave lens into the light path, and F1 ′ ′ ′ = It is made to be H2'-2 * F2 ''. Then, the distance between the objective lens 13 and the eye 11 to be examined matches H2 '. As a result, even when the front lens is replaced, the distance between the objective lens 13 and the eye 11 to be examined may be kept at H2 ', and it is not necessary to move the microscope body up and down.
However, the distance between the objective lens 13 and the front lens is adjusted to be H1 ′ when the front lens 6 is used, and to be H1 ′ ′ ′ when the front lens 6 ′ ′ is used. There is a need.
Here, the above-mentioned 1. As described in the above, even if the length of the arm is set according to the focal length of the front lens and the front lens is replaced, the distance between the front lens and the eye to be examined is the focal length of the front lens By maintaining the near state, adjustment of the distance between the objective lens 13 and the front lens can be fine adjustment only.

Furthermore, when the pre-lens is replaced with a third pre-lens with higher refractive power, the distance between the objective lens and the eye to be examined can be made constant by using the corresponding third objective auxiliary lens. can do.
Therefore, in the ophthalmic microscope of the present invention, it is preferable to have at least two objective auxiliary lenses for adjusting the focal length when replacing at least two front lenses. That is, in the case of having n front lenses (n 前置 2), it is preferable to have at least n objective auxiliary lenses.
And, in the pre-lens apparatus, it is preferable to arrange each pre-lens by shifting the position of the observation optical system in the optical axis direction by the difference in the focal length of the pre-lens. This eliminates the need for adjusting the distance between the objective lens 13 and the front lens.
In the following, an example of an embodiment of the inventive ophthalmic microscope using a front lens arrangement and an objective auxiliary lens will be described in detail with reference to the drawings.

Second Embodiment
FIGS. 4-9 are drawings which show typically the 2nd Embodiment of this invention.
FIG. 4 is a side view of the ophthalmic microscope 2 and FIG. 5 is a front view of the same, showing the observation of the anterior segment (eg, cornea, anterior capsule, sclera etc.) of the eye 11 to be examined. ing. Further, FIG. 6A is a schematic view of an observation optical system 300 (an observation optical system in which an objective auxiliary lens is provided on the side of an eye to be examined of an objective lens) of the ophthalmic microscope of FIGS. 4 and 5.
As shown in FIG. 4, the ophthalmologic microscope 2 includes an illumination optical system 1800 (not shown in FIG. 5) in addition to the observation optical system 300.
The observation optical system 300 can observe an observation target (the eye 11 in FIGS. 4 and 5). As shown in FIG. 4, the illumination optical system 1800 can illuminate a portion to be observed of the eye 11 to be examined.
In FIG. 4 and FIG. 5, the observation optical system has the front focal position U0 in front of the subject eye 11.

As clearly shown in FIG. 5, the observation optical system 300 has a right-eye observation optical system 300R and a left-eye observation optical system 300L. In FIG. 4, the entire configuration is shown for the right-eye observation optical system 300R, and only the objective lens 13 shared with the right-eye observation optical system 300R is shown for the left-eye observation optical system 300L. .
Although only one front lens 6 is shown in FIG. 5, in practice, at least two front lenses are held exchangeably by the front lens device.
Further, as clearly shown in FIG. 5, the optical axis O-300R of the right-eye observation optical system 300R and the optical axis O-300L of the left-eye observation optical system 300L pass through the objective lens 13, respectively.
In the present embodiment, the illumination optical system 1800 and the observation optical system 300 are housed in the ophthalmic microscope main body 12. In FIG. 4 and FIG. 5, the ophthalmic microscope main body 12 is shown by a dashed dotted line.

The illumination optical system 1800 shown in FIG. 4 includes an illumination light source 19, an optical fiber 1801, an output light aperture 1802, a condenser lens 1803, an illumination field aperture 1804, a collimator lens 1805 and a reflection mirror 1806. The optical axis of the illumination optical system 1800 is indicated by O-1800.
As shown in FIG. 4, the illumination light source 19 is provided outside the ophthalmic microscope main body 12 in the present embodiment. One end of an optical fiber 1801 is connected to the illumination light source 19. The other end of the optical fiber 1801 is disposed at a position facing the outgoing light stop 1802 of the ophthalmic microscope main body 12. The illumination light emitted from the illumination light source 19 is guided by the optical fiber 1801 and enters the condenser lens 1803 through the exit light diaphragm 1802.
The exit light stop 1802 acts to block a partial area of the exit of the optical fiber 1801. When the blocking area by the outgoing light diaphragm 1802 is changed, the outgoing area of the illumination light is changed. Thus, it is possible to change the irradiation angle by the illumination light, that is, the angle between the incident direction of the illumination light to the eye 11 to be examined and the optical axis of the objective lens 13.

The illumination field stop 1804 is provided at a position (position of x) optically conjugate with the front focal position U 0 of the objective lens 13. The collimator lens 1805 converts the illumination light having passed through the illumination field stop 1804 into a parallel light flux. The reflection mirror 1806 reflects the illumination light collimated by the collimator lens 1805 toward the objective lens 13. The light reflected by the reflection mirror 1806 is transmitted through the objective lens 13 and irradiated to the eye 11 to be examined.
The illumination light emitted to the subject eye 11 is reflected and scattered by the tissue of the retina. The reflected and scattered return light (also referred to as “observation light”) passes through the objective lens 13 and is incident on the observation optical system 300.

The observation optical system 300 is used to observe the subject eye 11 illuminated by the illumination optical system 1800 through the objective lens 13.
As shown in FIGS. 4 and 5, a variable magnification lens system 301 (lenses 301a, 301b, and 301c), a beam splitter 302 (a beam splitter for acquiring image information for displaying a television camera), an imaging lens 303, An image erecting prism 304, an eye width adjusting prism 305, a field stop 306, and an eyepiece lens 307 are included. The optical axis of the observation optical system 300 is indicated by O-300.

  As shown in FIG. 5, the beam splitter 302 of the right-eye observation optical system 300R separates a part of the observation light guided from the subject eye 11 along the right-eye observation optical system and takes a photographing optical system. Lead to 2000. The imaging optical system 2000 includes an imaging lens 2001, a reflection mirror 2002, and a television camera 2003. The image information acquired by the television camera 2003 is sent to a monitor (not shown) and displayed.

As shown in FIGS. 4 and 5, the image erecting prism 304 converts the inverted image into an erected image. The eye width adjusting prism 305 is an optical element for adjusting the distance between the left and right observation light paths according to the eye width (the distance between the left eye and the right eye) of the observer. The field stop 306 blocks the peripheral region in the cross section of the observation light to limit the observer's field of view. The field stop 306 is provided at a position (x position) conjugate with the front focal position U0 of the objective lens 13.
The right-eye observation optical system 300R and the left-eye observation optical system 300L may be configured to include a stereo variator configured to be insertable into and removable from the light path. The stereo variator is an optical axis position change element for changing the relative position of the optical axes O-300L and O-300R of the left and right observation optical systems guided by the left and right variable magnification lens systems 301, respectively. The stereo variator, for example, is retracted to a retraction position provided on the observer side with respect to the observation light path.

In the ophthalmologic microscope 2 shown in FIGS. 4 and 5, the observation optical system has a front focal position (indicated by U0 in front of the eye 11 when no lens is present between the objective lens 13 and the eye 11). )have. In the ophthalmic microscope 2, an objective auxiliary lens 17 is provided on the eye 11 side of the objective lens 13.
The objective auxiliary lens 17 can be set at a position closer to the objective lens 13 between the front focal position U0 and the objective lens 13, or released from that position. The objective auxiliary lens 17 is selected such that the in-focus point when it is set is the first focal point (U1) which is the anterior eye position of the eye to be examined.
6A shows the case where the objective auxiliary lens 17 is provided on the side of the eye 11 of the objective lens 13 in the observation optical system when observing the anterior segment of the eye 11 to be examined. In the present invention, as shown in FIG. 6 (B), the objective auxiliary lens 17 can be provided on the opposite side of the objective lens 13 to the eye 11 side to observe the anterior segment of the eye 11 to be examined.

FIG. 7 is a side view corresponding to FIG. 4 showing how the posterior eye portion (eg, retina) of the eye 11 to be examined is observed in the apparatus described in FIGS. 4 and 5. 8 is a front view corresponding to FIG. 5, and FIG. 9 (A) is a schematic view corresponding to FIG. 6 (A).
In FIGS. 7 and 8, the objective auxiliary lens 17 is released from the optical path of the observation optical system. The front lens 6 is set at a position closer to the subject eye 11 than the front focal position U0, and the focal point (second focus U2) of the subject eye 11 through the lens when it is set is the subject The position of the retina of the optometry 11 (posterior eye position) is set.
Even when the objective auxiliary lens 17 is provided on the opposite side of the objective lens 13 to the subject's eye 11 (see FIG. 6B), when observing the back-eye part of the subject's eye 11, FIG. It is necessary to release the objective auxiliary lens 17 as shown in FIG.

1: Pre-lens device 2: Ophthalmic microscope 300: Observation optical system 300R: Right-eye observation optical system 300L: Left-eye observation optical system 301: Variable-magnification lens system 302: Beam splitter 303: Imaging lens system 304: Image erecting prism 305: Eye width adjusting prism 306: Field stop 307: Eyepiece lenses 6, 6 ′ ′, 601 to 603: Front lens 8: Engaging portions 911, 912, 913: First arms 921, 922, 923: Second arm 931, 932, 933: Lens support frame 11: Eye to be examined 11a: Retina 11b: Lens 12: Ophthalmic microscope main body 13: Objective lens 14: Lens barrel 17, 17 ′ ′ ′: Objective assist Lens 1800: illumination optical system 1801: optical fiber 1802: outgoing light aperture 1803: condenser lens 1804: illumination field aperture 1805: collimation Lens 1806: Reflecting mirror 19: Illumination light source 2000: Photographing optical system 2001: Imaging lens 2002: Reflecting mirror 2003: Television camera F1, F1 ′, F1 ′ ′: Focal distance F2 from the objective lens, F2 ′ ′: front Focal length H1 ′, H1 ′ ′, H1 ′ ′ ′ of the stationary lens: distance H2, H2 ′, H2 ′ ′ between the objective lens and the front lens: distance between the objective lens and the eye to be examined O-300: observation optical system Optical axis O-300R: Optical axis O-300L of right-eye observation optical system: Optical axis O-1800 of left-eye observation optical system O-1: Optical axis U0 of illumination optical system: Front focal position U1: First focal point U2: The second focus

Claims (8)

In a front lens device used in an ophthalmic microscope having an observation optical system for observing an eye to be examined,
An engagement portion that can be mounted around the barrel of the ophthalmic microscope;
At least two front lens supports pivotally connected to the engagement portion and movable independently;
And a front lens held on each of the front lens supports;
The front lens support portion includes an arm portion rotatably connected to the engagement portion, and a front lens support frame connected to the arm portion,
The front lens is held by the front lens support frame,
A front lens apparatus characterized in that the front lens support is pivoted to make it possible to insert and remove the front lens into the light path of the observation optical system. The arm portion has a first arm rotatably coupled to the engagement portion, and a second arm pivotally connected to the first arm.
A front lens device, wherein the front lens support frame is pivotally connected to the second arm. The length of the said arm part differs according to the focal distance of the said front lens, The front lens apparatus of Claim 1 or 2 characterized by the above-mentioned. In an ophthalmic microscope having an observation optical system for observing an eye to be examined,
An ophthalmic microscope comprising the front lens device according to any one of claims 1 to 3.   An objective auxiliary lens that is insertable into and removable from the optical axis of the observation optical system and used to adjust the focal position closer to the eye to be examined than the objective lens of the observation optical system is provided. The ophthalmic microscope according to 4.   The ophthalmic microscope according to claim 5, wherein the objective auxiliary lens is a lens having a negative power.   The ophthalmic microscope according to claim 5, further comprising a switching mechanism that inserts or removes the objective auxiliary lens in conjunction with insertion or removal of the front lens. The ophthalmic microscope according to any one of claims 5 to 7, comprising at least n said objective auxiliary lenses when the number of said front lenses is n (n 2 2).