JPH11242191A - Bifocal contact iris - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a contact lens which can be easily produced at a low cost, which has a large visibility depth, and which gives bright view of a const. level continuously from near distance to far distance, by forming a diaphragm comprising a light-shielding thin film in the center part of a soft contact lens and forming an optical pupil of <= a specified diameter in the center. SOLUTION: A light-shielding thin film is formed on the surface center of a soft contact lens 1 with no degree by using an opaque dye which can be used for a soft contact lens 1 in such a manner that the thin film is in almost same size as the diameter of iris and that a transparent part is left in the center. Thus, a diaphragm 3 and optical iris 2 having <=1.8 mm diameter, namely, an optical pinhole is formed. Any color can be used for the diaphragm as far as it is opaque. This contact iris for both of hyperopia and myopia can be used fitted to an eye almost same as a normal contact soft lens. The proper diameter of the center optical pupil 2 differs depending on the degree of myopia and presbyopia, and the diameter is decreased smaller with the higher degree of myopia or presbyopia. However, an iris having >=0.5 mm diameter is easy for use.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a contact lens. In particular, if a soft contact lens called a colorless contact lens having no power is diverted, the embodiment of the present invention can be manufactured in almost the same process.
However, strictly speaking, the present invention is not a lens but an aperture (iris), and does not necessarily need to be made of a lens or serve as a lens.

[0002]

2. Description of the Related Art A conventional bifocal contact lens uses a soft contact lens with different refractive indices at a central portion and a peripheral portion thereof and uses them for near and far vision.

[0003]

However, the method of giving different refractive indexes to one soft contact lens as described above is based on the fact that the combination of the refractive indexes differs for each wearer and that the degree of the distance is increased. Most of them were made to order because they had to be rebuilt and the price was high. In addition, not only light passing through an appropriate refractive index portion but also light passing through an inappropriate refractive index portion is guided into the pupil without being blocked, so that there is considerable individual difference in the visibility. Further, as the presbyopia progresses, the depth of view that can be clearly seen by the near refractive index portion becomes extremely limited as in general reading glasses.

The present invention does not have a double refractive index, is easier and cheaper to manufacture than conventional products, has a large depth of field, and has a constant level of brightness over a very short to long distance. It is an object of the present invention to provide a bifocal vision correction tool that allows vision.

[0005]

In order to achieve the above object,
The present invention focuses on the iris or iris rather than the lens. The present invention allows a stop to be made on a contact lens so that it can be worn on the eyeball, with a diameter of 1.8 at the center.
An optical pupil of mm or less is formed by making the part transparent or making a hole. This is, in principle, the same as the fact that if you look at the outside world through a sufficiently small hole, you can clearly see from extreme distant views to extreme near views without distinguishing between hyperopia, myopia and presbyopia. However, there is a prejudice that the outside world usually seen through a small hole has a narrow view, but it is hard to notice that this phenomenon is continuously established up to the surface of the eyeball. It was found that by actually making the contact, the narrow field of view was almost eliminated, and there was a possibility of practical use.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described based on embodiments with reference to the drawings. The embodiment in FIG.
Soft contact lens with no degree using opaque dye that can be used for soft contact lens (1)
By forming a light-shielding thin film in the center of the surface of the iris, leaving a transparent portion having a size of about the diameter of the iris and a diameter of 0.5 mm to 1.2 mm at the center thereof, the stop (3) and the optical pupil ( 2),
That is, an optical pinhole is formed. Of course, the color of the aperture (3) may be anything as long as it is opaque, but here the whole is simply black. FIG. 3 is a reference external view of this embodiment. In the case of actual wearing, the large iris in which the iris cannot be seen is thus eerie, so a more realistic embodiment will be described below.

[0007]

In the embodiment shown in FIG. 2, the stop (3) is divided into an inner side and an outer side in consideration of the appearance of a light-shielding thin film forming the stop (3). On the outside, the iris picture (5) is drawn using a plurality of opaque pigments similar to the preceding paragraph. FIG. 4 is a reference external view of this embodiment. Since the central optical pupil actually overlaps with the wearer's pupil and cannot be distinguished, the sense of incongruity is almost eliminated.

[0008]

The bifocal contact iris of the present invention can be worn almost in the same manner as a normal soft contact lens. The appropriate diameter of the central optical pupil (2) depends on the degree of myopia and presbyopia, but as the degree increases, the appropriate diameter decreases. However, the smaller the diameter of the optical pupil (2), the darker the field of view when wearing it. If the degree is not advanced, the diameter can be clearly seen even if it is large, but the effect is extremely limited if it exceeds one boundary line around 1.8 mm. More realistically, it would be appropriate to commercialize the product in the range of 0.5 to 1.2 mm. When worn, it is surprising that the optical pupil (2) is not so narrow, even though it is exactly the size of a pinhole. If the diameter is in the range of 0.5 to 1.2 mm, the field of view is slightly dark,
Except immediately after wearing, I am not worried much. It is like wearing pale sunglasses. Instead, anything from near to far, regardless of myopia, hyperopia, or presbyopia, looks good. Even if you look close and suddenly look far, the appearance is almost the same. What is particularly important is that you are looking at the same central part of the eye both near and far.
Objects at all distances can be continuously tracked at the center of the eye without being switched, without any switching.

[Brief description of the drawings]

FIG. 1 is a plan view showing the simplest embodiment of a bifocal contact iris.

FIG. 2 is a plan view showing an embodiment in which a pupil and an iris are drawn on the surface of the stop.

FIG. 3 is a reference external view of the simplest embodiment of a bifocal contact iris.

FIG. 4 is a reference external view of an embodiment in which a pupil and an iris are drawn on the surface of the stop.

[Explanation of symbols]

 Reference Signs List 1 soft contact lens 2 optical pupil 3 aperture 4 pupil picture 5 iris picture

Claims (1)

[Claims] An optical pupil (2) having a diameter of 1.8 mm or less is provided at the center of the soft contact lens (1) by providing an aperture (3) made of a light-shielding thin film at the center of the soft contact lens (1). A bifocal contact iris characterized by being formed.