JP3447764B2 - Disc type intraocular lens - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an intraocular lens which is implanted in the eye instead of a crystalline lens whose function is impaired due to a cataract or the like. The present invention relates to a disc type intraocular lens which is integrally formed of the same material and has a closed curve portion surrounding the lens portion on the support portion.

[0002]

2. Description of the Related Art An intraocular lens to be implanted in an eye instead of a crystalline lens whose function is impaired by a cataract or the like is composed of a substantially circular lens portion and a support portion for supporting the lens portion in the eye. However, in general, a one-piece intraocular lens is one in which the support portion and the lens portion are integrally formed of the same material,
This is distinguished from a two-piece or three-piece intraocular lens in which the support portion is formed separately from the lens portion and is fixed to the lens portion.

In this case, since the supporting portion of the two-piece or three-piece intraocular lens is made of a material different from that of the lens portion, the supporting portion is made of a material having sufficient elasticity and flexibility, and at the same time, having sufficient elasticity. It is possible to relatively freely select a material having various strengths. On the other hand, since it is necessary to provide a mounting hole or the like for fixing the support portion to the lens portion, the effective area of the lens portion is limited, and the manufacturing process is relatively complicated.

In this respect, the one-piece intraocular lens does not need to be provided with a mounting hole or the like in the lens portion, so that a large effective area of the lens portion can be secured and the manufacturing process can be relatively simplified. It has become possible to be. However, in the one-piece intraocular lens, since the supporting portion must be made of the same material as the lens portion, the degree of freedom in selecting the material is limited, and a material that has sufficient elasticity and flexibility and strength is not necessarily required. Can't choose. For this reason, conventionally, attempts have been made to provide elasticity, flexibility and strength by forming the support portion into an appropriate shape.

By the way, there is a type of one-piece intraocular lens in which a circular or polygonal closed curve portion surrounding the lens portion is provided in the support portion (for example, International Publication No. 91).
/ 15166 pamphlet (1991)), which is generally called a disc type intraocular lens. This disc type intraocular lens has an advantage that it is firmly fixed in the eye by the closed curve portion after being inserted into the eye.

[0006]

However, the above-mentioned conventional disc type intraocular lens is of a type which is not provided with a closed curve portion in the support portion but only includes a support arm portion along an open curve (for example, a special table). Compared with Japanese Patent Laid-Open No. 3-503253), there is a drawback that the insertion cannot be done unless the incision is large when inserting it into the eye. That is, if the closed curve portion is a perfect circle, the size of the incision needs to be substantially equal to the diameter of the perfect circle, and the incision needs to be much larger than the size of the lens part. Also, if the closed curve portion is made polygonal or elliptical, the incision can be made smaller than in the case of making it a perfect circle, but it will be much larger than that of the support curve portion having the above open curve. There is a need. Moreover, if you make it polygonal or elliptical,
After insertion into the eye, the shape of the lens capsule, which should be a perfect circle, becomes a shape similar to a polygon or an ellipse, causing distortion, and the corners of the closed curve part locally cover a part of the lens capsule. There is also a problem that it is not preferable because it is strongly pressed.

The present invention has been made to solve the above-mentioned problems, and an object thereof is to make it possible to make the incision portion at the time of intraocular insertion relatively small and to keep it well in the eye after insertion. As described above, it is an object of the present invention to provide a disc type intraocular lens having a support portion having a sufficient mechanical strength while having an appropriate elasticity and excellent flexibility.

[0008]

DISCLOSURE OF THE INVENTION In order to solve the above problems, a disk type intraocular lens according to the present invention comprises (1)
A lens part, a closed curve part formed along a closed curve surrounding the lens part and a supporting member for holding the lens part in the eye, and the lens part for fixing the closed curve part to the lens part. In a disk type intraocular lens having a support portion having a support arm portion continuously extended and integrally connected to the closed curve portion by extending a part of the outer peripheral portion of the lens portion, A midline connecting the widthwise midpoints of the first root portions rising from the outer peripheral portion toward the closed curve portion is a curve that curves to one side with respect to the diametrical direction passing through the center point of the lens portion. And a middle line connecting the midpoints of the width direction of the second root portion rising from the closed curve portion toward the lens portion is the other with respect to the diameter direction passing through the center point of the lens portion. Formed to be a curve that curves to the side Further, the width of each of the root portions is formed so as to become gradually smaller toward the middle of the lens portion and the closed curve portion, and as a mode of this constitution 1, (2) In the disc type intraocular lens having the configuration 1, the first root portion and the second
Among the contour shapes on both sides in the width direction of at least one root portion of the root portion, the contour shape on one side is a convex curved shape toward the midline, and the contour shape on the other side is the root The base end portion of the portion has a curved shape that is convex toward the middle line, and is formed into a concave curve shape toward the middle line from the base end portion toward the intermediate portion. As a configuration of these configurations 1 and 2, (3) In the disc type intraocular lens of configuration 1 or 2, the closed curve portion is formed along a perfect circle. As a characteristic configuration and as one of the configurations 1 to 3, (4) Configurations 1 to 3
In any one of the configurations 1 to 4, the contour shape of the support arm portion is a combination of a plurality of curved lines having different curvatures. As an aspect, (5) In the disc type intraocular lens according to any one of configurations 1 to 4, three support arm portions are provided symmetrically with respect to a center of the lens portion as a center of symmetry. It was done.

[0009]

According to the above configuration 1, the shape of the support arm portion connecting the closed curve portion and the lens portion is formed in the width direction of the first root portion rising from the outer peripheral portion of the lens portion toward the closed curve portion. The second root that is formed so that the center line connecting the points is a curve that curves to one side with respect to the diametrical direction that passes through the center point of the lens part, and that rises from the closed curve part toward the lens part The center line connecting the middle points of the width direction of the portion is formed to be a curve that curves to the other side with respect to the diametric direction passing through the center point of the lens portion, and the width of each root portion is the same as the above. By forming the support arm so as to become gradually smaller toward the middle of the lens part and the closed curve part, the supporting arm part has appropriate elasticity and extremely excellent flexibility, and at the same time has sufficient mechanical strength. Became. For this reason, when inserting this disc type intraocular lens into the eye, it is possible to very easily press and close the closed curve portion to the extent of contacting the outer peripheral portion of the lens portion with tweezers or a dedicated tool, etc. In this way, there is no risk of damage or deformation even when compressed, and the original shape can be completely restored. Therefore, it becomes possible to reduce the size of the incision portion to about the outer diameter of the lens portion.

Further, according to the configuration 2, among the contour shapes on both sides in the width direction of at least one of the first root portion and the second root portion, the contour shape on one side is defined by the center line. To a convex curve shape, and the contour shape on the other side is a convex curve shape toward the midline at the base end portion of the root portion, and the midline extends from the base end portion toward the middle portion. By forming a concave curved shape toward the eye, it can be made more flexible while maintaining strength, which makes it easier to insert into the eye.

Further, according to the constitution 3, by making the closed curved portion a perfect circle, the fixation after the insertion can be made sufficient, and at the same time, the possibility of adversely affecting the lens capsule after the insertion can be more completely eliminated. It will be possible.

Further, according to the structure 4, the curved shape of the support arm can be made more flexible by combining a plurality of curved lines having different curvatures. Further, as in the structure 5, Moreover, by providing three support arm portions symmetrically with the center of the lens portion as the center of symmetry, the advantages of the configurations 1 to 4 can be more effectively brought out.

[0013]

EXAMPLES plan view of the disk-type intraocular lens according to a first embodiment of the first embodiment Figure 1 the present invention, FIG 2 is a side view of the first embodiment, FIG. 3 is a partially enlarged view of FIG. 1 is there. The first embodiment will be described below with reference to these drawings.

In FIG. 1, reference numeral 1 is a lens portion, reference numeral 2
Is a support. The disc type intraocular lens is a support member for holding the lens portion 1 in the eye around the lens portion 1, and includes a closed curve portion 21 formed along a circular curve surrounding the lens portion 1. , A support consisting of three support arm portions 22 which extend part of the outer peripheral portion of the lens portion 1 to fix the closed curved portion 21 to the lens portion 1 and are continuously and integrally coupled to the closed curved portion 21. The part 2 is formed. Three support arms 22 are symmetrically provided with the same shape with the center O of the lens unit 1 as the center of symmetry.

Both the lens portion 1 and the support portion 2 are made of polymethylmethacrylate (PMMA). Here, the lens portion 1 is a convex lens having a substantially circular shape in a plan view, and the diameter of the lens is about 5 mm. The lens unit 1 is not limited to the convex lens, and a concave lens, a plano-convex lens, a plano-concave lens, a meniscus lens, an aspherical lens, or the like can be used as necessary.

The closed curve portion 21 has a circular shape with a diameter of about 11 mm centered on the center O of the lens portion 1. The support arm portion 22 includes a first root portion 22a that rises from the outer peripheral portion of the lens portion 1 toward the closed curve portion 21, and a second root portion 22b that rises from the closed curve portion 21 toward the lens portion 1, and these. It has an intermediate part 22c in which the extension parts from each of the root parts 22a and 22b become one. In addition, the center line 22 connecting the midpoints in the width direction of the root portions 22a and 22b
The starting point of d is formed to be a curve that curves in mutually opposite sides with respect to the diametrical direction passing through the center point O of the lens portion 1, and the width of each root portion 22a, 22b is the middle portion 2
2c, it becomes gradually smaller, and the middle part 2
2c is formed to have a substantially constant width (thickness).

The shape of the support arm portion 22 will be described more specifically below.

Now, the first root portion 22a of the support arm portion 22
In the vicinity of, the curve connecting the midpoints in the width direction of the support arm portion 22 is a midline 22d, and the rising points on both sides of the first root portion 22a from the outer periphery of the lens portion 1 are P1 and P2, respectively.
, P0 is the midpoint between P1 and P2, and the diameter direction of the lens portion 1 passing through the midpoint P0 is the diameter direction LD1. Similarly, in the vicinity of the second root portion 22b, the rising points on both sides of the second root portion 22b from the inner circumference of the closed curve portion 21 are P4 and P5, and the midpoints of P4 and P5 are P6 and the middle point, respectively. A diametrical direction of the lens portion 1 passing through the point P6 is defined as a diametrical direction LD2. The change points of the curves representing the contour lines on both sides of the support arm portion 22 in the width direction are defined as P3, P7, and P8, respectively.

Then, the median line 22d extends in the diametrical direction L from one start point P0 toward the closed curve portion 21.
It becomes a curve that curves counterclockwise in the figure of D1, and its end point is the middle point P6 of the second root portion. In this case, the angle θ1 made by the tangent to the median line 22d at the point P0 with respect to the diametrical direction LD1 is about 40 °, while the angle θ2 made by the tangent to the median line 22d at the point P6 with respect to the diametrical direction LD2 is about 40 °. It is 30 °. Note that θ1 and θ2 are 0 to 45
It may be in the range of °.

Here, the curves representing the contour of the support arm 22 on one side in the width direction, that is, the curves rising from the point P1 and ending at the point P6, are the curves P1 P3 and P3.
P4, curve P4 P5, curve P5 P9, curve P9 P6
It is a curve that connects and. A curve representing the contour of the other side of the support arm portion 22 in the width direction, that is, a curve rising from the point P2 and ending at the point P7 is a curve P2 P10.
And a curve P10P7 are connected.

Next, the shape of the support arm portion 22 is changed to the lens portion 1
This is specifically shown by the coordinate value of each point and the value of the radius of curvature of each curve in the XY coordinates with the center O of the as the origin. Each of these values is as follows.

XY coordinates P0; X = 1.7960, Y = -1.7390 P1; X = 2.2152, Y = -1.1588 P2; X = 1.2296, Y = -2.1767 P3; X = 2.5283, Y = -1.5802 P4; X = 2.6914, Y = -1.5411 P5; X = 3.2547, Y = -1.2699 P6; X = 5.0613, Y = 0.7733 P7; X = 5.1016, Y = -0.4332 P8; X = 5.1171, Y = 0.1715 P9; X = 4.9594 , Y = 0.3382 P10; X = 0.6647, Y = -0.2468 Curve curve P1 P3 rising from the radius P1 of curvature P1 P3; 0.30 Curve P3 P4; Linear curve P4 P5; 3.0 Curve P5 P9; 5.809 Curve P9 P6; 0.60 Rise from point P2 Curve Curve P2 P10; 5.939 Curve P10 P7; 0.50 As shown in FIG. 2, the support arm portion 2 forms an angle α with the plane orthogonal to the optical axis of the lens portion 1 depending on the purpose.
(Α = 0 to 15 °).

Although not shown, the disc type intraocular lens described above is grasped by a grasping tool such as tweezers or a dedicated tool, and is inserted into the eye through an incision formed by incising a part of the cornea of the eyeball. , For example, fixed within the lens capsule.

In this case, since the supporting arm portion 22 has the above-described shape, the supporting arm portion 22 has appropriate elasticity and extremely excellent flexibility, and at the same time has sufficient mechanical strength. became. Therefore, when the disc type intraocular lens is inserted into the eye, the closed curve portion 21 can be compressed very easily by tweezers or a dedicated tool to the extent that the closed curved portion 21 contacts the outer peripheral portion of the lens portion 1. Further, there is no danger of being damaged or deformed even when compressed in this way, and the original shape can be completely restored. Therefore, it becomes possible to insert the cut portion easily even if the cut portion is pressed down to the outer diameter of the lens portion 1. Moreover, the closed curve portion 22 has a circular shape, and the support arm portion 22
Since three are provided in a symmetrical positional relationship, after insertion, the closed curve portion 21 returns to a nearly perfect circle, distorting the crystalline lens, or applying a large local pressing force. It can be firmly fixed in the eye with moderate elasticity. Furthermore, since it has sufficient strength, there is no risk of damage during handling.

Second Embodiment FIG. 4 is a plan view of a disk type intraocular lens according to a second embodiment of the present invention, and FIG. 5 is a partially enlarged view of FIG. The second embodiment will be described below with reference to these drawings. In addition, since the basic configuration of this embodiment is similar to that of the above-described first embodiment, the corresponding portions are denoted by the same reference numerals, and in the following description, only points characteristic of the second embodiment will be mainly described. explain.

The features of the second embodiment are as follows.

(1) First root portion 2 of the supporting arm portion 22
2a and the second root portion 22b of the widthwise both sides of the contour shape, the contour shape on one side is a convex curve shape toward the median line 22d, the contour shape on the other side is the first root Part 2
2a and the second root portion 22b at the base end portion, the center line 2
A point that is formed in a curved shape that is convex toward 2d, and that is formed in a curved shape that is concave toward the midline 22d from the base end portion toward the intermediate portion 22c.

(2) First root portion 22a to intermediate portion 22c
The point that the degree of curvature at the portion transitioning to is increased so that a part of the intermediate portion 22c continuing from this transition portion is substantially parallel to the shape of the outer peripheral portion of the lens portion 1.

Hereinafter, these characteristic points will be described more specifically.

Now, the first root portion 22a of the support arm portion 22
In the vicinity of, the rising points on both sides of the first root portion 22a from the outer circumference of the lens unit 1 are P1 and P2, respectively,
The lens portion 1 passing through the middle point P0 and the middle point P0 of P1 and P2
The diametrical direction is defined as the diametrical direction LD1. Similarly, in the vicinity of the second root portion 22b, the rising points on both sides of the second root portion 22b from the inner circumference of the closed curve portion 21 are respectively set to P1.
The midpoints of 3, P14 and P13, P14 are designated as P15, and the diameter direction of the lens portion 1 passing through the midpoint P15 is designated as the diameter direction LD2. The change points of the curves representing the contour lines on both sides of the support arm portion 22 in the width direction are respectively P3, P4, P5, P6, P7 and P8.
, P9, P10, P11, P12.

Then, in the first root portion 22a, of the contour shapes on both sides in the width direction of the first root portion 22a, the contour shape on one side, that is, the contour shape on the side rising from the point P1 is The contour shape is along a curve P1 P5 having a large curvature and convex toward the midline 22d, and a subsequent curve P5 P6 having a relatively small curvature. Further, the contour shape on the other side, that is, the contour shape on the side rising from the point P2 is a curve P2 having a convex shape toward the midline 22d and a relatively small curvature.
The contour shape is along P3 and a curve following the curve, which is a curve in which a curve P3 P4 which is concave toward the midline 22d and has a relatively large curvature is connected. Therefore, the first root portion 22
The degree of bending increases in the portion that transitions from a to the intermediate portion 22c, and a portion of the intermediate portion 22c that continues from this transition portion becomes substantially parallel to the shape of the outer peripheral portion of the lens unit 1.

In the second root portion 22b, of the contour shapes on both sides in the width direction of the second root portion 22b,
The contour shape on one side, that is, the contour shape on the side rising from the point P13 is a contour shape along a curve P13P11 that is convex toward the midline 22d. Further, the contour shape on the other side, that is, the contour shape on the side rising from the point P14 is the center line 22d.
The contour shape is along a curve P14P12 that is convex toward and a curve that follows the curve P12P10 that is concave toward the median line 22d.

Here, the angle .theta.1 formed by the tangent to the median line 22d at the point P0 with respect to the diametrical direction LD1 is about 20.degree.
On the other hand, the angle θ2 formed by the tangent to the median line 22d at the point P15 with respect to the diametrical direction LD2 is about 40 °. Note that θ1 and θ2 may be in the range of 0 to 45 °.

A curve representing the contour of the support arm portion 22 on one side in the width direction, that is, a curve rising from the point P1 and ending at the point P14 is a curve P1 P5 and a curve P5 P.
6, curve P6 P7, curve P7 P8, curve P8 P10
And a curve P10P12 and a curve P12P14 are connected. Further, a curve representing the contour on the other side in the width direction of the support arm portion 22, that is, a curve rising from the point P2 and ending at the point P13 is a curve P2 P3 and a curve P3 P4,
It is a curve obtained by connecting the curves P4 P9, P9 P11 and P11 P13.

Next, the shape of the support arm portion 22 is changed to the lens portion 1
This is specifically shown by the coordinate value of each point and the value of the radius of curvature of each curve in the XY coordinates with the center O of the as the origin. Each of these values is as follows.

XY coordinates P0; X = -0.9109, Y = -2.3038 P1; X = -0.3859, Y = -2.47 P2; X = -1.49841, Y = -2.0012 P3; X = -1.100, Y =- 2.7357 P4; X = -0.7262, Y = -3.1338 P5; X = -0.465, Y = -3.0042 P6; X = -0.33, Y = -3.0311 P7; X = 0.3487, Y = -3.0875 P8; X = 2.0017, Y = -2.7437 P9; X = 2.0522, Y = -2.8632 P10; X = 4.5045, Y = 0.0838 P11; X = 4.6295, Y = 0.0481 P12; X = 4.6412, Y = 0.2829 P13; X = 5.12, Y =- 0.0215 P14; X = 4.9737, Y = 1.2152 P15; X = 5.0846, Y = 0.6014 Curve curve P1 P5; 0.27 curve P5 P6; Straight curve P6 P7; 3.00 Curve P7 P8; 4.87 Curve P8 P10; 4.37 Curve P10P12; 0.38 Curve P12P14; 0.90 Curve rising from the point P2 Curve P2 P3; 1.00 Curve P3 P4; 0.43 Curve P4 P9; 5.00 Curve P9 P11; 4.50 Curve P11P13; 0.25 Although not shown, the support arms 2, depending on the purpose, the angle with respect to a plane perpendicular to the optical axis of the lens unit 1 α (α = 0
It is similar to the first embodiment in that it is formed so as to form about 15 °.

According to this second embodiment, the first root portion 2
2a and the second root portion 22b on both sides in the width direction, the contour shape on one side is a convex curve shape toward the midline 22d, and the contour shape on the other side is the base end of the root portion. In the part, the curved shape is convex toward the midline 22d, and
By forming a curved shape that is concave toward the midline from the base end toward the intermediate portion 22c, it is possible to make it more flexible while maintaining strength, thereby inserting into the eye. It has become possible to make the work easier.

In the second embodiment, the case where both the first root portion and the second root portion are provided with the above-mentioned characteristic point (1) is mentioned, but this is one of the root portions. Part is the characteristic point
You may make it provide (1).

Further, in each of the above-mentioned embodiments, the supporting arm portion 22
Although the example in which three are provided is given, the number of supporting arms may be one or three or more. Further, the material forming the lens portion 1 and the supporting portion 2 may be any material that can be used as a lens material and at the same time has appropriate elasticity.
Besides, for example, hydroxyethyl methacrylate, silicone, polysulfone, fluorine-based polymer, polycarbonate and the like can be used.

[0040]

As described in detail above, in the disk type intraocular lens of the present invention, the shape of the supporting arm portion connecting the closed curve portion and the lens portion is raised from the outer peripheral portion of the lens portion toward the closed curve portion. The center line connecting the widthwise middle points of the first root portion is formed so as to be a curve that curves to one side with respect to the diametrical direction passing through the center point of the lens portion. The center line connecting the widthwise midpoints of the second root portion rising toward the lens portion is formed so as to be a curve that curves to the other side with respect to the diameter direction passing through the center point of the lens portion. Further, since the width of each root portion is formed so as to gradually decrease toward the middle of the lens portion and the closed curve portion, this support arm portion has appropriate elasticity and extremely excellent flexibility. At the same time, have sufficient mechanical strength It could be. Therefore, when inserting this disc type intraocular lens into the eye, it is possible to extremely easily press the closed curved portion to the extent of contacting the outer peripheral portion of the lens portion with tweezers or a dedicated tool, and In this way, there is no risk of damage or deformation even when compressed, and the original shape can be completely restored. Therefore, it becomes possible to reduce the size of the incision to about the outer diameter of the lens.

Further, of the contour shapes on both sides in the width direction of at least one of the first root portion and the second root portion, one of the contour shapes is convex toward the midline. It has a curved shape, and the contour shape on the other side has a curved shape that is convex toward the midline at the base end portion of the root portion, and is concave toward the midline from the base end portion toward the intermediate portion. By forming the curved shape, it is possible to make it more flexible while maintaining the strength, which makes it easier to insert into the eye.

Furthermore, by making the closed curve portion a perfect circle, it is possible to sufficiently fix the lens after insertion and to completely eliminate the possibility of adversely affecting the lens capsule after insertion.

Further, the curved shape of the support arm is formed by combining a plurality of curves having different curvatures,
The support arm can be made more flexible, and the support arm can be symmetrically arranged with the center of the lens part as the center of symmetry.
By providing one, it is possible to more effectively bring out the advantages of the present invention.

[Brief description of drawings]

FIG. 1 is a plan view of a disk type intraocular lens according to a first embodiment of the present invention.

FIG. 2 is a side view of the first embodiment.

3 is a partially enlarged view of FIG.

FIG. 4 is a plan view of a disk type intraocular lens according to a second example.

FIG. 5 is a partially enlarged view of FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Lens part, 2 ... Support part, 21 ... Closed curve part, 22 ... Support arm part, 22a ... 1st root part, 22b ... 2nd root part, 22c ... Intermediate part, 22d ... Midline, LD1, LD2 ... diametrical.

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-1-285258 (JP, A) JP-A-3-503253 (JP, A) US Patent 4863463 (US, A) International Publication 91/015166 (WO, A1) (58) Fields surveyed (Int.Cl. ⁷ , DB name) A61F 2/16 A61F 2/14 WPI (DIALOG)

Claims (5)

(57) [Claims] 1. A lens part, a support member for holding the lens part in the eye, and a closed curve part formed along a closed curve surrounding the lens part, and the closed curve part is fixed to the lens part. In order to extend a part of the outer peripheral portion of the lens portion and a support portion having a support arm portion that is continuously and integrally coupled to the closed curve portion, in a disc type intraocular lens, the support arm portion is , A middle line connecting the midpoints in the width direction of the first root portion rising from the outer peripheral portion of the lens portion toward the closed curved portion is curved to one side with respect to the diameter direction passing through the center point of the lens portion. A center line connecting the midpoints of the width direction of the second root portion rising from the closed curve portion toward the lens portion passes through the center point of the lens portion in the diametrical direction. To the other side It is formed as, and the disk-type intraocular lens characterized in that it is formed so as gradually decreases as the width of each root portion toward the middle between the lens portion and the closed curve portion. 2. The disc type intraocular lens according to claim 1, wherein one of the contour shapes on both sides in the width direction of at least one of the first root portion and the second root portion. The contour shape on the side of is a curved shape that is convex toward the midline,
The contour shape on the other side has a convex curved shape toward the center line at the base end portion of the root portion, and a concave curve toward the center line from the base end portion toward the middle portion. A disk-type intraocular lens characterized by being formed in a shape. 3. The disc type intraocular lens according to claim 1 or 2, wherein the closed curve portion is formed along a perfect circle. 4. The disk-type intraocular lens according to claim 1, wherein the contour shape of the support arm portion is formed by combining a plurality of curved lines having different curvatures. Disc type intraocular lens. 5. The disk type intraocular lens according to any one of claims 1 to 4, wherein three supporting arm portions are provided symmetrically with a center of the lens portion being a symmetrical center. Disc type intraocular lens.