JP5346503B2 - Progressive power lens and manufacturing method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a progressive-power lens capable of obtaining a proper corrective add diopter corresponding to an apparent adjustment power generated by refractive correction of a wearer, and also to provide the method of manufacturing the same. <P>SOLUTION: This invention relates to a progressive-power lens 100 comprising a farsight portion 101 with a farsight diopter, a nearsight portion 102 with a nearsight diopter, and an intermediate portion 103 in which a refractive power progressively varies in accordance with an add diopter between the farsight portion 101 and the nearsight portion 102. The add diopter is adjustable in accordance with the correction degree of a wearer. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a progressive power lens and a manufacturing method thereof.

  Examples of the spectacle lens having a vision correction function such as presbyopia include a single focus lens, a multifocal lens, and a progressive power lens. Among these lenses, progressive-power lenses not only provide different power fields with a single lens, but they do not have the same boundaries as multifocal lenses. Yes.

  Conventional spectacle lenses are generally made to order because the shape of the refracting surface varies depending on lens data prescribed for each wearer (for example, spherical power, astigmatism power, addition power, etc.). For this reason, when manufacturing a progressive power lens, a semi-finished lens with different addition powers at a predetermined pitch (generally in increments of 0.25D) due to the necessity of simplifying the manufacturing process and reducing costs. (Hereinafter referred to as a semi-finished lens) is prepared in advance, a semi-finished lens having an addition power prescribed to the wearer is selected from these, and any refractive surface (process) of the selected semi-finished lens is selected. Are processed according to the prescription of the wearer to obtain a finished spectacle lens. (For example, refer to Patent Documents 1 to 3.)

A semi-finished lens is obtained by processing one refracting surface (usually the outer surface) of a lens into an aspherical surface (referred to as a progressive surface) according to the addition, and the addition is fixed at this stage. . In the semi-finished lens, the prescription surface (usually the inner surface) opposite to the processed progressive surface is processed into a spherical surface or a toric surface. As described above, the semi-finished lens shares the same lens within a certain power range, and thus plays a major role in cost reduction such as heating cost and inventory reduction.
Japanese Patent Laid-Open No. 10-175149 JP 2004-133024 A Japanese Patent No. 3845251

  By the way, in the case of a person who has performed refractive correction for myopia or hyperopia by wearing glasses, etc., there is a difference between the apparent adjustment power caused by refractive correction and the actual eye adjustment power depending on the correction power. I know it will happen.

  However, the conventional progressive-power lens has a problem that even if a semi-finished lens having a prescription addition is used for a person who has performed such refractive correction, an appropriate correction addition power cannot be obtained. .

  Therefore, the present invention has been proposed in view of such conventional circumstances, and progressive refraction capable of obtaining an appropriate correction addition power according to the apparent adjustment force generated by the refractive correction of the wearer. An object of the present invention is to provide a force lens and a method for manufacturing the same.

In order to achieve the above object, a progressive-power lens according to the present invention includes a distance portion containing a distance power, a near portion containing a near power, and a distance portion and a near portion. A progressive power lens having an intermediate portion in which the refractive power changes progressively according to the addition power, and the actual adjustment power of the wearer 's eyes and the apparent adjustment power generated by the refractive correction of the wearer Based on the difference , the addition power is adjusted according to the correction power of the wearer.

Further, the method of manufacturing a progressive-power lens according to the present invention includes a distance part containing a distance power, a near part containing a near power, and an addition power between the distance part and the near part. A progressive power lens manufacturing method comprising an intermediate portion in which the refractive power changes progressively according to a semi-finished lens having different addition powers at a predetermined pitch. And select the addition power on either or both sides of the semi-finished lens based on the difference between the wearer's actual eye adjustment and the apparent adjustment of the wearer's refractive correction. It is characterized by performing a process of adjusting according to the correction power of the wearer.

  As described above, according to the present invention, it is possible to give the progressive addition lens an appropriate correction addition power according to the apparent adjustment force generated by the refractive correction of the wearer. The lens can be manufactured at low cost while simplifying the manufacturing process.

Hereinafter, a progressive-power lens to which the present invention is applied and a manufacturing method thereof will be described in detail with reference to the drawings.
In addition, in the drawings used in the following description, in order to make the features easy to understand, there are cases where the portions that become the features are enlarged for the sake of convenience, and the dimensional ratios of the respective components are not always the same as the actual ones. Absent. In addition, numerical values and the like exemplified in the following description are examples, and the present invention is not necessarily limited to them, and can be appropriately changed and implemented without changing the gist thereof.

  Also, in the following description, “upward”, “downward”, “vertical direction”, “horizontal direction”, etc. of the lens are based on the positional relationship of the lens when wearing spectacles. The positional relationship (up / down / left / right) of FIG. Of the two refracting surfaces constituting the lens, the object side surface is referred to as an “outer surface” and the eyeball side surface is referred to as an “inner surface”.

  In the progressive-power lens 100 to which the present invention is applied, for example, as shown in FIG. 1, a distance portion 101 containing a power for viewing a distance (referred to as a distance power) is disposed on the upper side, and the vicinity is viewed. The near portion 102 containing the power of the hour (referred to as the near power) is disposed below, and the intermediate portion 103 in which the refractive power gradually changes between the distance portion 101 and the near portion 102 is disposed. Has a structured. In addition, before this progressive focus lens 100 is processed into a spectacle lens 100a (shown by a solid line in the figure) (a state before the lashing process), it has a circular shape in plan view as shown by a two-dot chain line in the figure. doing.

  When manufacturing the progressive-power lens 100, semi-finished lenses with different additions are prepared in advance at a predetermined pitch (generally in increments of 0.25D) in order to simplify the manufacturing process and reduce costs. One semi-finished lens having an addition power prescribed to the wearer is selected from these, and any refractive surface (referred to as a prescription surface) of the selected one semi-finished lens is used. The spectacle lens 100a is finally obtained.

  The semi-finished lens is obtained by processing one refracting surface (usually the outer surface) of a lens into an aspherical surface (referred to as a progressive surface) according to the addition, and the addition is fixed at this stage. In the semi-finished lens, the prescription surface (usually the inner surface) opposite to the processed progressive surface is processed into a spherical surface or a toric surface.

Here, the addition power is the power that has joined the near portion with respect to the distance power, and is a value represented by the difference between the distance power and the near power. In addition, the addition power of the semi-finished lens is expressed as “lowest addition to maximum addition” (for example, 0.50D to 4.00D), and the semifinishing in which the addition power is varied in steps of 0.25D within this range. A lens is prepared in advance.
Further, as the addition, a value defined by the surface refractive power can be used. Or the value defined by the refractive power in the state which the wearer wore can be used.

  In the progressive-power lens 100 to which the present invention is applied, after selecting one semi-finished lens from a plurality of semi-finished lenses having different addition powers at a predetermined pitch, the selected semi-finished lens is selected. One or both surfaces of the lens are processed to adjust the addition according to the correction power of the wearer.

  Specifically, the progressive addition lens 100 in which the addition power is adjusted according to the correction power of the wearer is subjected to processing for adjusting the addition power based on the apparent adjustment force generated by the wearer's refractive correction. Has been.

  As described above, in the case of a person who has performed refractive correction for myopia or hyperopia by wearing glasses, etc., the apparent adjustment force caused by the refractive correction and the actual eye adjustment force depend on the correction power. It is known that there will be a difference in

Here, the apparent adjustment force (Acc) [D] generated by the wearer's refraction correction is the actual eye adjustment force Ac [D], the distance between the eyes and the lens L [m], and the wearer Is the value obtained by the following formula (1) or (2), where R [D] is the correction frequency.
Acc = Ac (1-LR) ² (1)
Acc = Ac (1-2L ・ R) ... (2)

In the progressive-power lens 100 to which the present invention is applied, the addition power is adjusted as shown in [1] and [2] below based on the apparent adjustment force Acc generated by this refractive correction. That is,
[1] When the corrective power of the wearer is plus (+) in the distance portion 101, the apparent adjustment force is smaller than the actual adjustment force (Acc <Ac), so that the addition increases. Adjust to.
[2] When the corrective power of the wearer is negative (−) in the distance portion, the apparent adjustment force becomes larger than the actual adjustment force (Acc> Ac), so that the addition decreases. adjust.
Alternatively, the addition is adjusted as shown in [3] and [4] below.
[3] When the corrective power of the wearer is plus (+) in the near portion, the apparent adjustment force is smaller than the actual adjustment force (Acc <Ac). adjust.
[4] When the corrective power of the wearer is minus (−) in the near portion, the apparent adjustment force (Acc> Ac) is larger than the actual adjustment force, so that the degree of addition decreases. adjust.

  In this way, if the correction power is minus power (myopic eye), the apparent adjustment force becomes larger than the actual adjustment force, so that the addition power is adjusted in a direction that decreases. Thereby, it is possible to reduce the shake and distortion peculiar to the progressive refraction lens. On the other hand, if the correction power is a positive power (hyperopic eye), the apparent adjustment force is smaller than the actual adjustment force, so that the addition is adjusted in consideration of this. Thereby, it is possible to correct the near-use power correctly and to prevent the vicinity from being difficult to see due to insufficient correction.

  Further, the addition pitch adjusted in accordance with the correction power of the wearer is preferably smaller than the addition pitch (in 0.25 D increments) of the semi-finished lens described above, specifically, in 0.01 D increments. It is preferable that Thereby, it is possible to obtain an appropriate correction addition power according to the apparent adjustment force Acc generated by the refractive correction of the wearer.

  In addition, for one semi-finished lens that performs such processing, it is based on the case of selecting a semi-finished lens having the addition prescribed to the wearer and the apparent adjustment force generated by the refractive correction of the wearer. There is a case where a semi-finished lens having the addition closest to the addition is selected.

  In the case of the former, since the addition prescribed to the wearer and the addition entered on the semi-finished lens match, the addition is adjusted according to the correction power of the wearer, and then the prescribed addition Does not give prescribers or wearers the misunderstanding that

  On the other hand, in the latter case, the adjustment amount with respect to the prescription surface of the semi-finished lens described later can be reduced. In this case, use a semi-finished lens without engraving addition, adjust the addition according to the correction power of the wearer, and then engrave the prescribed addition on the lens. The occurrence of the misunderstanding described above can be prevented in advance.

  NC processing can be used for the processing for adjusting the addition to the progressive power lens described above. Specifically, by using an NC processing device controlled by numerical control, processing for adjusting (increasing / decreasing) the addition power according to the correction power of the wearer can be accurately performed on the progressive addition lens. Is possible.

  As described above, according to the present invention, it is possible to give the progressive addition lens an appropriate correction addition power corresponding to the apparent adjustment force generated by the refractive correction of the wearer. Further, according to the present invention, it is possible to manufacture such a progressive power lens at a low cost while simplifying the manufacturing process.

  The present invention is not limited to an outer surface progressive addition lens with an outer surface as a progressive surface and an inner surface as a prescription surface, but an inner surface with a progressive surface and a prescription surface as a composite surface. The present invention can also be applied to lenses having a prescription surface on the surface and outer surface. Moreover, it is also possible to perform the process for adjusting the addition mentioned above on the progressive surface side of these lenses.

  Furthermore, the present invention can also be applied to a double-sided progressive-power lens having both surfaces as progressive surfaces. The double-sided progressive addition lens gives addition power by combining the longitudinal / lateral refractive power applied to the outer surface and the vertical / lateral refractive power applied to the inner surface. Also in this case, it is possible to perform the process for adjusting the addition mentioned above.

  Hereinafter, the effects of the present invention will be made clearer by examples. In addition, this invention is not limited to a following example, In the range which does not change the summary, it can change suitably and can implement.

Example 1
In Example 1, a progressive-power lens to which the present invention is applied when the wearer receives a prescription with a correction power of S-6.00D and an addition power of 2.00D will be described.
In Example 1, first, a semi-finished lens having an addition of 2.00D was selected from semi-finished lenses having different additions in units of 0.25D. As shown in FIG. 2A, the semi-finished lens has a progressive surface (aspheric surface) on the outer surface and a prescription surface (spherical surface) on the inner surface. And specific refractive powers (distance power and near power) in the near portion.

Next, the apparent adjustment force produced by the wearer's refraction correction was determined by the above formula (1).
That is, if the near working distance is 0.25 m, for example, the necessary adjustment force is 4.00D and the prescribed addition power is 2.00D, so the wearer's eye adjustment force is 2.00D ( = 4.00D-2.00D). In this way, the wearer obtains an adjustment power of 4.00D for viewing the near 0.25 m by combining the eye adjustment power of 2.00D and the lens addition power of 2.00D.

In this case, when the distance L between the eyes and the lens is, for example, 0.012 m, the actual eye adjustment force Ac is 2.00 D, and the wearer's correction power R is −6.00 D. The apparent adjustment force Acc caused by the correction is obtained by the above equation (1).
Acc = 2.00 (1-0.012 × −6.00) ² = 2.30D
It has become.

  Here, since the adjustment force necessary for viewing the near 0.25 m is 4.00D, the shortage is 1.70D (= 4.00D-2.30D), and the addition power of the lens is 1.70D. Is an appropriate value. Therefore, since the addition of 2.00 D is given to the semi-finished lens, it is necessary to adjust the addition in a direction to reduce the addition by 0.30 D (= 2.00 D-1.70 D).

Therefore, by performing NC processing for reducing the addition power by 0.30D on the prefinished surface of the semi-finished lens, a progressive power lens having both aspheric surfaces as shown in FIG. 2B was obtained.
As described above, according to the present invention, it is possible to obtain a progressive addition lens having an appropriate correction addition power corresponding to an apparent adjustment force generated by the refractive correction of the wearer.

(Example 2)
In Example 2, a progressive-power lens to which the present invention is applied when the wearer receives a prescription with a correction power of S + 6.00D and an addition power of 2.00D will be described.
In Example 2, first, a semi-finished lens suitable for the correction power S + 6.00D and the addition power 2.00D was selected from the semi-finished lenses having different outer surface base curves. As shown in FIG. 3 (a), this lens has a spherical outer surface and an inner surface (aspherical surface) in which a progressive surface and a prescription surface are combined. In FIG. The specific refractive power (distance power and near power) in the distance part and near part is illustrated.

Next, the apparent adjustment force produced by the wearer's refraction correction was determined by the above formula (1).
That is, if the near working distance is 0.25 m, for example, the necessary adjustment force is 4.00D and the prescribed addition power is 2.00D, so the wearer's eye adjustment force is 2.00D ( = 4.00D-2.00D). In this way, the wearer obtains an adjustment power of 4.00D for viewing the near 0.25 m by combining the eye adjustment power of 2.00D and the lens addition power of 2.00D.

In this case, if the distance L between the eyes and the lens is, for example, 0.012 m, the actual eye adjustment force Ac is 2.00 D, and the wearer's correction power R is +6.00 D. The apparent adjustment force Acc generated by the following equation (1)
Acc = 2.00 (1-0.012 × 6.00) ² = 1.72D
It has become.

  Here, since the adjusting force necessary for viewing the near 0.25 m is 4.00D, the shortage is 2.28D (= 4.00D-1.72D), and the addition power of the lens is 2.28D. Is an appropriate value. Therefore, it is necessary to give an adjusted addition 2.28D on the inner surface.

Therefore, a progressive power lens as shown in FIG. 3B was obtained by subjecting the prefinished surface (inner surface) of the semi-finished lens to NC processing for giving an addition of 2.28D.
As described above, according to the present invention, it is possible to obtain a progressive addition lens having an appropriate correction addition power corresponding to an apparent adjustment force generated by the refractive correction of the wearer.

(Example 3)
In Example 3, as in Example 1, the wearer received a prescription with a correction power of S-6.00D and an addition power of 2.00D, but apparently caused by the above-mentioned refractive correction of the wearer. Considering that the adjusting force is 2.30D, a semi-finished lens having an addition of 1.75D was selected as shown in FIG.
In this case, since the addition of the lens is 1.70D, which is an appropriate value, the addition may be adjusted in a direction to reduce the addition by 0.05D (= 1.75D-1.70D).

Therefore, by applying NC processing for reducing the addition power by 0.05D to the prefinished surface of the semi-finished lens, a progressive power lens having both aspheric surfaces as shown in FIG. 4B was obtained.
As described above, according to the present invention, it is possible to obtain a progressive addition lens having an appropriate correction addition power corresponding to an apparent adjustment force generated by the refractive correction of the wearer.

Example 4
In the fourth embodiment, as in the second embodiment, the wearer receives a prescription with the correction power S + 6.00D and the addition power 2.00D, but the apparent adjustment force generated by the above-described refractive correction of the wearer. Is 1.72D, and an addition of 2.25D is given to the inner surface as shown in FIG. 5 (a).
In this case, since the addition power of the lens is an appropriate value of 2.28D, it is only necessary to adjust the addition power by 0.03D (= 2.28D-2.25D) on the outer surface.

Therefore, by performing NC processing for increasing the addition by 0.03D on the outer surface of the lens having the addition power of 2.25D on the inner surface, the progression that both surfaces become aspherical as shown in FIG. A refractive lens was obtained.
As described above, according to the present invention, it is possible to obtain a progressive addition lens having an appropriate correction addition power corresponding to an apparent adjustment force generated by the refractive correction of the wearer.

(Example 5)
In Example 5, as in Example 1, the wearer received a prescription with a correction power of S-6.00D and an addition power of 2.00D. As a double-sided progressive power lens, FIG. As shown in FIG. 4, the lens gives the addition power by the combination of the longitudinal / lateral refractive power applied to the outer surface and the vertical / lateral refractive power applied to the inner surface. In this lens, as shown in FIG. 6A, the outer surface and the inner surface are progressive surfaces (aspherical surfaces), and in FIG. Refractive power (longitudinal component / lateral component) is illustrated.

  In this case, since the apparent adjusting force generated by the above-mentioned refractive correction of the wearer is 2.30D in the vertical and horizontal directions, 1.70D is an appropriate value for the addition of the lens in the vertical and horizontal directions. Therefore, it is only necessary to adjust the addition in the vertical and horizontal directions so as to reduce the addition by 0.30D (= 2.00D-1.70D).

Therefore, by performing NC processing for reducing the addition power by 0.30D in the vertical and horizontal directions on the inner surface of the semi-finished lens whose outer surface is completed, the progressive power on both sides as shown in FIG. I got a lens.
As described above, according to the present invention, it is possible to obtain a progressive addition lens having an appropriate correction addition power corresponding to an apparent adjustment force generated by the refractive correction of the wearer.

  In Examples 1 to 5 above, the standard working value is 0.25 m for the near working distance and 0.012 m for the distance between the eyes and the lens. Changes. For this reason, it is possible to adjust the addition power more strictly by using values according to the actual wearer for these numerical values. In Examples 1 to 5, the apparent adjustment force caused by the refractive correction of the wearer is obtained by the above equation (1), but can also be obtained by the above equation (2).

FIG. 1 is a plan view showing an example of a progressive power lens to which the present invention is applied. FIG. 2 shows a case of Example 1, where (a) is a conventional lens, and (b) is a sectional view showing a progressive-power lens to which the present invention is applied. FIG. 3 shows a case of Example 2, where (a) is a conventional lens, and (b) is a cross-sectional view showing a progressive-power lens to which the present invention is applied. FIG. 4 is a case of Example 3, where (a) is a conventional lens, and (b) is a cross-sectional view showing a progressive power lens to which the present invention is applied. FIG. 5 shows a case of Example 4, wherein (a) is a conventional lens, and (b) is a sectional view showing a progressive-power lens to which the present invention is applied. FIG. 6 shows a case of Example 5, where (a) is a conventional lens, and (b) is a sectional view showing a progressive-power lens to which the present invention is applied.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 100 ... Progressive-power lens 100a ... Lens for spectacles 101 ... Distance part 102 ... Near part 103 ... Middle part

Claims (15)

A distance part containing a distance power, a near part containing a near power, and an intermediate part where the refractive power gradually changes according to the addition power between the distance part and the near part. A progressive-power lens comprising
The addition power is adjusted according to the correction power of the wearer based on the difference between the actual adjustment power of the wearer 's eyes and the apparent adjustment power generated by the refractive correction of the wearer. Progressive power lens. The apparent adjustment force (Acc) [D] generated by the refractive correction of the wearer is Ac [D] as the actual eye adjustment force and L [m] as the distance between the eyes and the lens. When the frequency is R [D],
Acc = Ac (1-LR) ²
Or Acc = Ac (1-2L · R)
The progressive-power lens according to claim 1, wherein the progressive power lens is a value obtained by:   The progressive-power lens according to claim 1 or 2, wherein any one or both surfaces of the lens is processed to adjust the addition according to the correction power of the wearer.   4. The progressive-power lens according to claim 3, wherein any one or both surfaces of the lens constitute a progressive surface that gives the addition power prescribed to the wearer.   5. The addition pitch adjusted according to the correction power of the wearer is smaller than the addition pitch of a semi-finished lens obtained by changing the addition at a predetermined pitch. A progressive-power lens according to any one of the above.   The progressive addition lens according to claim 1, wherein the addition is a value defined by a surface refractive power.   The progressive addition lens according to any one of claims 1 to 5, wherein the addition power is a value defined by a refractive power in a state worn by the wearer. A distance part containing a distance power, a near part containing a near power, and an intermediate part where the refractive power gradually changes according to the addition power between the distance part and the near part. A method of manufacturing a progressive power lens comprising:
Select one semi-finished lens from semi-finished lenses with different addition powers at a predetermined pitch, and adjust the actual eye's eye adjustment power on either or both sides of the semi-finished lens. A process for producing a progressive-power lens, characterized in that, based on a difference from an apparent adjustment force caused by a wearer's refractive correction, a process of adjusting the addition power according to the correction power of the wearer is performed. As the apparent accommodation force (Acc) [D] generated by the wearer's refraction correction, the actual eye accommodation force is Ac [D], and the distance between the eyes and the lens is L [m]. When the frequency is R [D],
Acc = Ac (1-LR) ²
Or Acc = Ac (1-2L · R)
The method according to claim 8, wherein a value obtained by: is used. When performing the processing,
If the corrective power of the wearer is positive in the distance portion, adjust in the direction that the addition increases,
10. The method of manufacturing a progressive-power lens according to claim 8, wherein when the wearer's correction power is negative in the distance portion, the addition power is adjusted in a decreasing direction. When performing the processing,
If the corrective power of the wearer is positive in the near-use part, adjust in the direction to increase the addition,
10. The method of manufacturing a progressive-power lens according to claim 8, wherein when the wearer's correction power is negative in the near portion, the addition power is adjusted in a decreasing direction.   The amount of addition to be adjusted is determined based on information on at least one of a near distance assumed at the time of wearing or a distance between an eye and a lens. A manufacturing method of the progressive-power lens as described in 2.   The progressive pitch according to any one of claims 8 to 12, wherein an addition pitch adjusted according to a correction power of the wearer is made smaller than an addition pitch of the semi-finished lens. A manufacturing method of a refractive power lens.   The method for producing a progressive power lens according to any one of claims 8 to 13, wherein a semi-finish lens having an addition power prescribed to the wearer is selected as the one semi-finish lens. .   The semi-finished lens having an addition power closest to the addition power based on an apparent adjustment force generated by the refractive correction of the wearer is selected as the one semi-finishing lens. The manufacturing method of the progressive-power lens as described in any one.

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