JP2612853B2 - Progressive multifocal lenses for eyeglasses - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial application field> The present invention relates to a spectacle lens, and in particular, a refractive power gradually changes from above to below (continuously) substantially near the center in the horizontal direction of the lens. The present invention relates to a progressive multifocal lens group for spectacles having an increasing section.

<Related Art> A progressive multifocal lens is a type of spectacle lens for presbyopia, and the line of sight passes over the spectacle lens in response to the line of sight moving downward from far vision to near vision. It is a spectacle lens having a section in which the refractive power along the path (main gazing line) is gradually changed (continuously increased).

The position of the main gaze in this progressive multifocal lens should be arranged at a position where the line of sight passes most frequently, and usually, near the center of the spectacle lens in the horizontal direction, from above. It is generally arranged downward, and is disclosed in JP-B-49-3595 or JP-B-52-20271.

Therefore, as described above, the progressive multifocal lens has a section in which the refractive power is continuously changing. Therefore, the refractive surface portion having astigmatism, which can also be called "twist" of the refractive surface, is formed. Coexist.

Although the existence of this astigmatism is a fatal drawback for a progressive multifocal lens, at least it makes the astigmatism along the main line of sight substantially harmless (within about 1/8 diopter). It is possible, and most of the progressive multifocal lenses currently on the market employ such a primary gaze (sometimes called a navel meridian or navel curve).

<Problems to be Solved by the Invention> On the other hand, a progressive multifocal lens is a kind of spectacle lens for presbyopia, and presbyopia is roughly classified into hyperopia and myopia. However, the contents of the inconvenience in the naked eye state are completely different.

That is, aside from extremely intense hyperopia, myopia and astigmatism, many people with hyperopic presbyopia are people who can see distant but hardly near, and conversely, many myopic presbyopia. The person who sees is "a person who can see near but hard to see far away".

Therefore, people with hyperopic presbyopia tend to be dissatisfied with the far vision, and those with myopic presbyopia tend to be dissatisfied with the near vision, and progressive multifocal glasses, which should originally be "bifocal glasses". This is why some people wear their glasses and take off their glasses to avoid eye fatigue when looking away or near.

That is, a person who wants to take off glasses when looking at a distance is a person who can see the distance well without glasses (hyperopia presbyopia). A person who can see the vicinity well (myopic presbyopia).

These people were dissatisfied with the far or near vision (or near vision + intermediate vision) of the progressive multifocal glasses they wore.

Thus, a person with hyperopic presbyopia gives better far vision, while a person with myopic presbyopia gives better near vision (or near vision + intermediate vision). It has been desired to provide a progressive multifocal lens having a simple design configuration.

However, there was no prior art corresponding to these findings. That is, in the conventional progressive design, there was no concept of distinguishing between hyperopia and myopia and differentiating the progressive aberration distribution.

Therefore, an object of the present invention is to change the aberration distribution design between the first lens group for hyperopic presbyopia and the second lens group for myopic presbyopia, so that It is an object of the present invention to provide a progressive multifocal lens group for spectacles capable of obtaining a wider far vision and a wider near vision for myopic presbyopia.

<Means for Solving the Problems> The present invention has been made to achieve the above object, and the refractive power gradually increases from above to below in the vicinity of the center of the lens in the horizontal direction. A progressive multifocal lens group for spectacles, including a first lens group for hyperopic presbyopia and a second lens group for myopic presbyopia, wherein the astigmatism is 0.5 diopter The area S of the following area is set to the area A above the distance eye point of each progressive multifocal lens.
And a partial area B from the distance eye point to the near power measurement point and a lower area C from the near power measurement point.
In the case of a hyperopic presbyopia lens in which the average power of distance power is +1.00 diopter or more, the respective areas of the above A, B, and C regions are Ap, Bp, Cp, In addition, the average frequency of far vision is -1.
When the respective areas of the above A, B, and C regions in the case of the myopic presbyopia lens of 00 diopters or less are Am, Bm, and Cm, respectively, Sp = Ap + Bp + Cp and Sm = Am + Bm + Cm, and the hyperopic presbyopia When the addition power of the ophthalmic lens and that of the myopic presbyopia lens are equal, the first lens group and the second lens group satisfy Ap> Am for all addition power ranges.
By providing an astigmatism distribution that satisfies the relationship of Cp <Cm or Bp + Cp <Bm + Cm, a wider distance vision is provided to the hyperopic presbyopia, and the myopic presbyopia is also provided. Provision of a progressive multifocal lens that provides a wider near field for the ophthalmic lens and is tailored to both the hyperopic and myopic presbyopia. It is another object of the present invention to provide a progressive multifocal lens group for spectacles, characterized in that:

More specifically, a positive distance power is generally prescribed for hyperopic presbyopia, and a negative distance power is prescribed for myopic presbyopia. Strictly speaking, the distinction should be made based on the sign of the average power of the distance power (spherical power + 1/2 astigmatism power). However, the effect of the present invention is not necessarily limited to this, and the average power of the distance power is used. The effect of the present invention can be sufficiently obtained only by distinguishing the design between the case where is more than +1.00 diopter and the case where is less than -1.00 diopter.

Therefore, at least when the average power of the distance power is +1.00 diopter or more, a design focusing on the far vision is performed.
In the case of -1.00 diopter or less, the near field or near field + intermediate field is emphasized. Various methods can be used as a design method emphasizing each visual field here, but the most effective method is to increase the area of each effective visual field.

The area of the effective visual field referred to here is the area of the area where the astigmatism (excluding astigmatism due to the prescribed power of astigmatism) is 0.50 diopters or less on the refracting surface of the progressive multifocal lens. .

However, progressive multifocal lenses, unlike other multifocal lenses, do not have a distinct field of view.

Conversely, it is a feature of the progressive multifocal lens that the boundary between the visual fields such as the far visual field, the intermediate visual field, and the near visual field is not clearly defined. Nevertheless, since the progressive multifocal lens is a spectacle lens for presbyopia, an area for viewing a distant area, an area for viewing a near area, and an intermediate position between the two are provided. There is an area to see.

Therefore, it is possible to design such that only one of the visual field areas (one or two) of these visual field areas is emphasized, and the area of the corresponding effective visual field is widened.
Therefore, in the present invention, a boundary line is set for each field of view that does not originally have a clear boundary line,
The area of each effective field of view was specified. That is, in the progressive multifocal lens, the astigmatism has an area S of a region of 0.5 diopter or less, a portion above the distance eye point position of the lens, and a portion from the distance eye point position to the near power measurement point. Divide into three areas below the near power measurement point,
Let A, B, and C be respectively corresponding to the areas of the effective visual fields of the far field, the intermediate field, and the near field.

That is, S = A + B + C. Further, when the average power of the distance power of the lens is 1.00 diopter or more, p is added, and when the average power is -1.00 diopter or less, the suffix m is added. That is, Sp = Ap + Bp + Cp Sm = Am + Bm + Cm At this time, as described above, a design that emphasizes the far vision for hyperopic presbyopia is performed, that is, Ap> Am, and as described above, near vision or intermediate vision + near vision for myopic presbyopia. The design is made with emphasis on the visual field, that is, Cp <Cm or Bp + Cp <Bm + Cm.

<Effects> By implementing the present invention, a progressive multifocal lens that is comfortable and easy to use, adapted to each characteristic, for people with hyperopic presbyopia and also for people with myopic presbyopia. Can be provided.

<Embodiment (1)> FIG. 1 shows a progressive multifocal lens according to an embodiment of the present invention.
Reference numeral 1 denotes a lens for the right eye which has a distance power of S + 2.00 and is used for a person with hyperopic presbyopia.
1.50 is a right-eye lens used for people with myopic presbyopia.

The shaded areas in Examples 1 and 2 have astigmatism of 0.50.
The area beyond the diopter, and the + and ○ marks indicate the distance eye point position and the near power measurement position, respectively. The effective horizontal viewing area of 1 and 2 is indicated by two horizontal lines passing through each point. (Areas without hatching) are three areas It is divided into

Here, Ap> Am and Cp <Cm, providing a wider (up and down) far vision for people with hyperopic presbyopia, and also for people with myopic presbyopia. It provides a wider (horizontally) near field of view and a design tailored to each characteristic.

The addition power in 1 and 2 is 1.00 diopter.

<Embodiment (2)> FIG. 2 shows a progressive multifocal lens according to an embodiment of the present invention.
Reference numeral 1 denotes a right-eye lens having a distance power of S + 1.25 and used for a person with hyperopic presbyopia, and 2 has a distance power of S-4.
It is a right-eye lens 00 for myopic presbyopia.

The meaning of each symbol, mark, hatching, etc. is the same as in FIG.

Here, Ap> Am and Bp + Cp <Bm + Cp, providing a wider (horizontally) far vision for people with hyperopic presbyopia, and also for people with myopic presbyopia. Wider intermediate vision +
It can be seen that the design is tailored to each characteristic by providing a near vision.

The addition power in 1 and 2 is 2.50 diopters.

<Embodiment (3)> FIG. 3 shows an embodiment in which the present invention is applied to a left-right symmetric progressive multifocal lens. 2 is a right-eye lens which has a distance power of S-3.00 and is used for people with myopic presbyopia.

In 1 and 2, a slightly inclined vertical dotted line indicates the axis of symmetry of each lens.

In addition, the meanings of other symbols, marks, and oblique lines are the first.
It is the same as the figure.

Here, Ap> Am and Cp <Cm, providing a wider distance vision for people with hyperopic presbyopia, and a wider near field for people with myopic presbyopia. It can be seen that the design is provided according to each characteristic by providing a view.

The add power in 1 and 2 is 3.00 diopters.

<Effects of the Invention> As described above, according to the present invention, a plurality of design configurations can be combined into one progressive multifocal lens product according to the distance power of a presbyopic patient wearing the progressive multifocal lens. It can be included in the item, even for hyperopic presbyopia patients,
In addition, a progressive multifocal lens that is comfortable and easy to use and can be provided to myopic presbyopia patients according to their characteristics.

[Brief description of the drawings]

FIGS. 1 to 3 are explanatory views showing first to third embodiments of the present invention, respectively. 1 ... Progressive multifocal lens whose average power of distance power is +1.00 diopter or more, 2 ... Progressive multifocal lens whose average power of distance power is -1.00 diopter or less, + mark ... Point position ○ mark: near dioptric power measurement position Shaded area: area where astigmatism exceeds 0.50 diopters Ap, Bp, Dp and Am, Bm, Cm: area other than the shaded area is near the distance eye point position Name of the area divided by the horizontal line passing through the utility frequency measurement position.

Claims (1)

(57) [Claims] 1. A first lens group for hyperopic presbyopia and a myopic presbyopia, comprising a section near the center of the lens in the horizontal direction where the refractive power gradually changes from above to below. A progressive multifocal lens group for spectacles including a second lens group for the eye, wherein the astigmatism has an area S of an area of 0.5 diopter or less, an area A above the distance eye point of each progressive multifocal lens,
Partial area B from the distance eye point to the near power measurement point
A, B in the case of a hyperopic presbyopia lens in which the average power of the distance power is +1.00 diopter or more, which is divided into three regions, that is, a lower region C from the near power measurement point. , C areas are Ap, Bp, Cp, respectively, and the average power of distance power is -1.
When the respective areas of the A, B, and C regions in the case of a myopic presbyopia lens of 00 diopters or less are Am, Bm, and Cm, Sp = Ap + Bp + Cp and Sm = Am + Bm + Cm, and the hyperopic presbyopia is obtained. When the addition power of the ophthalmic lens is equal to that of the myopic presbyopia lens, the first lens group and the second lens group satisfy the relationship of Ap> Am for all addition power ranges. Having a distribution of astigmatism satisfying the relationship of Cp <Cm or Bp + Cp <Bm + Cm, thereby providing a wider far vision for the hyperopic presbyopia,
It also provides a wider near vision for the myopic presbyopia lens, tailored to each of the characteristics for both the hyperopic and presbyopia. A progressive multifocal lens group for spectacles, wherein a progressive multifocal lens can be worn.