JPS63254415A - Visual acuity remedying device using two progressive multifocus lenses - Google Patents

Abstract

PURPOSE:To continue a visual field extending from a distant part to a near part, and also, to reduce the aberration by placing two progressive multifocus lenses in which codes of a joining degree are different, along the optical axis. CONSTITUTION:Main meridians M1, M2 of two progressive multifocus lenses 1, 2 are on the same plane, and allowed to cross vertically an optical axis OA. In such a case, a joining degree of the lens 1 is 2 diopters (D), and that of the lens 2 is -2D, therefore, a variation of the refracting power is offset and becomes instant by said arrangement. Accordingly, when the lenses 1, 2 are used jointly, there is the same effect as a single focus lens of 2D is installed and used, and when it is installed and used by removing the lens 2, a continuous visual field extending from a distant part to a near part is obtained. Also, when the lens 1 is made movable in the vertical direction, and the lenses 1, 2 are shifted relatively, the focus can be adjusted freely extending from a distant part to a near part.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention mainly relates to: A vision correction method 1 for visual acuity sufferers with weakened L'J nodes.

[Conventional technology]

Typical conventional eyeglass lenses for presbyopes include:
2! as shown in Figure 2! There is an n-focal lens. This lens has a part 21 for seeing far away and a part 22 for seeing near, and in theory two lenses with different refractive powers are arranged on one lens. This bifocal lens has a border between the 21 and 22 parts, giving the illusion of a pleasing appearance when used as eyeglasses, but many people still wear it today because it has little astigmatism and a wide field of view. .

Furthermore, a trifocal lens with a portion 23 for viewing intermediate distances has been developed as shown in Fig. 3, but recently, a progressive multifocal lens as shown in Figure A4 (a) has been developed. started to be used. FIG. 4(a) is a front view of a progressive multifocal lens, where M is the principal meridian passing approximately through the center of the lens. The progressive multifocal lens is roughly divided into three parts: a distance area 41, an intermediate area 42, and a near area 43, but each part is smoothly connected and the boundaries as shown in the figure are not visible. Figure 4(b) shows the main meridian fI! It shows the refractive power change on M. From the center of the distance vision part, the refractive power is enough to maintain 6 e of distance visual acuity, and on the F side from the center of the near vision part, the refractive power is enough to maintain near vision of 1 e. Between point A and point 11, the refractive power increases almost linearly,
Therefore, continuous visual acuity from far to near is ensured between the three Δ irises. As mentioned above, progressive multifocal lenses can provide continuous vision correction from far to near, and there is no boundary line like that of 2-severe point lenses.
He is also excellent in heptademia.

[Problem that the invention seeks to solve]

However, because conventional progressive multifocal lenses smoothly connect parts with different refractive powers to L&', astigmatism and distortion aberration occur, resulting in problems such as blurring, distortion, and shaking of the image. . It is impossible to completely eliminate these aberrations, so it is necessary to use a progressive multifocal lens. The biggest challenge for the first person is how to arrange these aberrations and how to create a spectacle lens that is easy to use. It is an object of the present invention to solve these problems and provide a vision correction device that has a good visual field with few aberrations.

[Means to solve the problem] Vision bridge IT using two progressive multifocal lenses of the present invention
:, 1°lr is a vision correction device using two optical lenses, both of which are:
A progressive multifocal lens in which the refractive power changes progressively in at least a portion of the principal meridian passing through approximately the center of the refractive surface, and the two progressive multifocal lenses are such that the changes in refractive power are in opposite directions. The optical system is characterized by a beam located along the optical axis.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1(a) shows a first practical example of the vision correction system of the present invention. Two progressive multifocal lenses 1 and 2 are arranged along the optical axis OA. 1 and 2 stops/l
The i glands M,,M, are in the same plane 1-, and the light ilI OA
It intersects with vertical 11°. Figure 1 (1)) and (
C) is a progressive multifocal lens and shows no change in refractive power on the principal meridian -1- of 7th lens i2. S,,S,,T,,T,do not represent the starting point or ending point of the change in refractive power. The lens l has a refractive power of 0 [diopter] (hereinafter abbreviated as [1)]. )
As you move downward, the bending force increases in a 0° [glandular manner], reaching 2[D] at TI. The increase in refractive power from point S1 to point T will hereinafter be referred to as addition power. The processing degree of lens I is 2 [1)]. Lens 2 has a refractive power of 2 [1)] at S, and then decreases to 11 [glandularly] to 0 at T.
[1)]. That is, it is a lens with an addition of 1f-2[D]. These two progressive multifocal lenses are shown in Figure 1(a).
By arranging it as shown in FIG. When used, the patient has the same effect as wearing a 2 [I)] monofocal lens. On the other hand, when the lens 2 is removed and worn, the visual acuity correction device of the present invention provides a continuous visual field from far to near, since the lens is the same as a conventional progressive multifocal lens. Furthermore, according to the research of the present inventor, by combining two progressive multifocal lenses with addition powers of different signs as in this embodiment,
It was found that the aberrations were canceled out by each other and the field of view was improved.

FIG. 5(a) shows a urethane nozzle according to a second embodiment of the present invention.
is movable in the vertical direction, and the ratio of 2/2 is fixed at 1.+1. FIGS. 5(b) and 5(C) each do not show the change in the refractive power of the lens 1.2. Lens 1 is S
1 becomes O[+)], and T becomes 3[1)]. On the other hand, Lesbian 2 is St (ON)], Tt Te 1-5 [D] There is Te. s, ~'r, the interval length is 100 [+nml, S
The distance between l and Tt is 50 [mm]. So two lenses! The increases in optical power per 116th length have different signs but are equal in magnitude. Move lens l to the fifth
As shown in the figure ((1), a point P of refractive power 1 [1)],
Assuming that the point S of lens 2 is combined, the overlapped portion of the two 1/lenses has an effect flj equivalent to that of a single focus lens of l[I)]. (Fig. 5 (C)) When lens l is further moved and point 1" of refractive power 1.5[1)] and Sl are aligned, the overlapping part of the lens is located at the center point of 1.5[1)]. t,
,! ,'-I can intercede with Reno's. , (Fig. 5 ('')) In this way, by moving the lens l, the present implementation (vision correction device of shi 1;
I can do a lot of work.

FIG. 1(a) shows a third embodiment of the present invention.

Lens 1 is fixed. The lens 2 moves together with the eyeball 1 with a slight movement. Figure (b) (
c) does not show the refractive power of lens 1.2. Lens l is a lens with an addition power of 2°5 [1)], which is -1 [+)] at Sl and 1.5 [I)] at T. Lens 2 is S, 0.5
[1)], Tt -0,5N)], addition -IN)]
The refractive power at approximately the center of the lens is 0[1)]. With lens 2 worn on cornea -1, direct your line of sight to the position where the refractive power of lens 1 is -0.5 [I)]
Then, the changes in refractive power are canceled out, and the refractive power of 10.5 [1)] is increased to 111 over the entire visual field. If you raise your line of sight and look at the position of l[+)] on lens 1, you will see I[+)]
refractive power can be obtained.

〔Effect of the invention〕

As explained in Situation 1 and 1 below, the addition power γ1 becomes 6 and 2
It is said that by arranging two point lenses along the optical axis, a continuous field of view from far to near can be obtained. A device with a visual field as wide as a single-focal lens is provided.

However, in the first embodiment, the lens 2 can be removed and the lens 1 alone can be used in the same way as a conventional progressive multifocal lens. If you spend a lot of time reading newspapers, miscellaneous papers, etc. at hand, why not use Lens 2 and 4'? You can also secure a field of vision as wide as glasses for near-term celebrations.

In addition, as explained in the second and third embodiments, by shifting the two lenses 411 pairs, it is possible to focus freely from far to near, and it is convenient for users It is as if you are using a single vision lens (a wider field of view is provided).

In the above explanation, we have described the case where the two progressive multifocal lenses completely cancel out the changes in refractive power, and the refractive power is constant over the entire visual field like a single vision lens.
The present invention is not limited to this. For example, the present invention also includes a case where the change in refractive power of lens 2 is not enough to cancel out the change in refractive power of lens 1, and in that case, a progressive lens with a very relaxed addition power is obtained, and It produces an effect as a near lens.

In addition, the numbers shown in the examples are used to make the explanation more concrete and easier to understand.In particular, the values of refractive power, etc. should be determined appropriately according to the 11 prescriptions of thinking. It is.

[Brief explanation of the drawing]

FIG. 1 shows a first embodiment of the present invention, and (a) is a layout diagram of two progressive lenses. (b) Diagram of changes in refractive power of H/Z 1. (
c) Diagram of refractive power change of lens 2. (d) Diagram of refractive power change due to two lenses. FIG. 2 is a front view of a conventional two-point lens. FIG. 3 is a front view of a secondary triple point lens. FIG. 71 shows a conventional progressive multifocal lens, (a) a front view. (b) Diagram of refractive power change along the principal meridian. FIG. 5 shows a second embodiment of the present invention, in which (a) the sh/z arrangement W
figure. (I>) Diagram of refractive power change of lens l. (C) Diagram of changes in refractive power of lens 2. ((I) A diagram showing the state in which the lens 1 is moved. (C) and (r) are diagrams of changes in refractive power due to the two lenses. Figure 0 is a third embodiment of the present invention, and (a) A diagram of the lens arrangement. (l)) Diagram of refractive power change of lens l. (c) Diagram of refractive power change of lens 2. 1...First progressive multifocal lens 2...
Second progressive multifocal lens OA... Light % I+ M,, M,... Principal meridian S,, S,... Starting point of refractive power change T,, T ,・
...From the end point of the change in refractive power" - Applicant: Seiml - Epson Corporation Fig. 2 Fig. 3 Fig. 4 (shi) o 5 CD) No. S1 sword (b) Fig. 5 (f)

Claims (1)

[Claims] A vision correction device using two optical lenses, wherein both of the two optical lenses are progressive multifocal lenses in which the refractive power changes progressively in at least a portion on the principal meridian passing approximately at the center of the refractive surface. The two progressive multifocal lenses are arranged so that the changes in refractive power are in opposite directions.
A vision correction device using two progressive multifocal lenses, which are arranged along the optical axis.