JP2012203189A - Method for designing progressive refractive power lens - Google Patents

Abstract

The present invention provides a progressive-power lens in which a clear vision width at an intermediate portion and a near portion is sufficiently wide and lateral performance is also good.
A method for designing a progressive-power lens for spectacles having a distance portion 11, a near portion 12 and an intermediate portion 13, which is suitable for distance vision, intermediate vision and near vision of a wearer. A step 100 for obtaining a wearer's clear vision width specification W including a clear vision width w1 of the portion 11, a clear vision width w2 of the intermediate portion 13, and a clear vision width w3 of the near portion 12, and a clear vision width specification W And a step 300 of designing a progressive-power lens based on spectacles specifications including: When obtaining the clear vision width specification W, the distribution of the side view and the front view is obtained for the distant vision distribution, and the distribution of only the front view is obtained for the intermediate vision and the near vision.
[Selection] Figure 3

Description

  The present invention relates to a method for designing a progressive-power lens for spectacles.

  Patent Document 1 describes that a spectacle lens design method with a thin edge thickness is provided in consideration of the wearer's characteristics relating to the use situation of the spectacle lens. According to the spectacle lens design method disclosed in Patent Document 1, the curvature radius on the object side and the curvature radius on the eyeball side of the spectacle lens are determined based on prescription data of the spectacle wearer. A first region where the wearer's use frequency is high and a second region where the spectacle wearer's use frequency is low are determined based on the rotation angle of the spectacle wearer's eyeball. Further, in this design method, the radius of curvature in the second region is continuously changed toward the peripheral portion in the direction in which the lens edge thickness becomes thinner than the radius of curvature determined based on the prescription data. It is characterized by correction.

  Patent Document 2 describes providing a lens that gives the wearer more satisfaction. The invention of Patent Document 2 relates to a method of determining a pair of spectacle lenses, by measuring the sagittal plane displacement for near vision with respect to the wearer's standard sagittal plane. An optimization target is then selected as a function of the measured deviation. The lens is determined by optimization with the selected target. In this way, a lens is obtained in which the near field perceived by the wearer is symmetric with respect to the midline. Thus, it is described that a wearer having a displaced sagittal plane obtains a larger near field of vision, and as a result, binocular vision is facilitated and visual acuity is improved.

  Patent Document 3 discloses a system and method for prescribing and / or preparing an ophthalmic lens to a wearer. The method of Patent Document 3 determines at least a wearer's individual visual movement pattern from the viewpoint of head movement and / or eye movement, and uses these patterns as known head movement and / or eye movement. Process with respect to the predetermined relationship between the characteristics of movement and the available ophthalmic lenses, and this process will result in a category of head movement or eye movement that can be used to recommend the ophthalmic lens to the wearer. Categorizing the wearer. The system includes a transmitter unit and a wearer-worn receiver that provides data to the interface. During testing, a standard set of frames is used and proximal and medium distance reading surfaces are used.

  Patent Document 4 describes that a spectacle lens design method and a manufacturing method thereof that can be worn more comfortably by an individual corresponding to the visual movement of the individual are described. In the design method of the patent document, the rotation angle of the head that is moved when the subject with the naked eye sees the object is measured, and the visual action index with the naked eye is calculated. Next, a lens is provisionally designed based on the obtained visual action index, and a direction in which an object can be seen through the provisionally designed lens is simulated. Then, the visual action index is corrected based on the obtained angle. This correction is performed until the visual motion index converges.

JP 2008-249828 A Special table 2008-511033 gazette Special table 2003-523244 gazette JP 2010-197484 A

  The progressive power lens is a distance portion that provides distance vision for viewing a distant image, a near portion that provides near vision for viewing a near image, and a distance image between distance vision and near vision. And an intermediate part for providing intermediate vision. The progressive-power lens is wide enough so that the distance portion, the intermediate portion, and the near portion do not interfere with the eye movement of the wearer (wearer, user) in the distance vision, intermediate vision, and near vision. It is desirable that the lens performance is not extremely deteriorated in a region other than the clear viewing width, for example, in the side of the intermediate portion and the near portion. In this specification, the clear vision width means a horizontal width (distance) on the lens at which unnecessary astigmatism is less than or equal to a specified value.

  However, Minkwitz's law is well known in the design of progressive power lenses. According to this law, when a progressive zone is provided in the Y-axis direction (vertical axis direction) of the lens, the progressive zone in the X-axis direction (horizontal direction). Astigmatism occurs at a rate twice the refractive power gradient. Therefore, if the clear vision width of the distance portion and the near portion is widened, the clear vision width of the intermediate portion is narrowed, and if the clear vision width of the near portion and the intermediate portion is widened, lateral astigmatism increases, The lens performance of the direction is reduced. The above-mentioned patent document describes a progressive refractive power that ensures a clear vision width that is wide enough for the line-of-sight movement of the wearer's distance vision, intermediate vision, and near vision, and that does not unnecessarily degrade the lens performance. A lens design method is not disclosed.

One aspect of the present invention is a method for designing a progressive-power lens for spectacles having a distance portion and a near portion having different visual powers, and an intermediate portion located between the distance portion and the near portion. Has the following steps.
1. Acquire specifications of wearer's clear vision width including distance vision clear vision width, intermediate vision clear vision width and near vision clear vision width suitable for wearer's distance vision, intermediate vision and near vision thing.
2. Design progressive-power lenses based on spectacles specifications including clear vision width specifications.

  Further, the step of obtaining the clear vision width specification is based on the direction of the wearer's line of sight and / or movement of the head, from the clear vision width of the distance portion, the clear vision width of the intermediate portion, and the clear vision width of the near portion. Determining each distribution of far vision, intermediate vision, and near vision, and determining each distribution is to obtain a distribution including lateral vision and front vision for the distance vision distribution; For near vision, it includes obtaining the distribution of only front vision.

  In intermediate vision and near vision, the intermediate and near vision parts are rarely used for side vision, and the wearing feeling is improved by securing a clear vision width for side vision in the intermediate and near vision areas. Can not expect so much. Therefore, in intermediate vision and near vision, the distribution of only the front vision is obtained, and converted to the clear vision width of the intermediate portion and the clear vision width of the near portion, so that the intermediate portion and near vision included in the clear vision width specification are converted. It is possible to prevent the clear vision width of the portion from becoming wider than necessary. As a result, in the step of designing individual progressive-power lenses, there is little deterioration in the lens performance in the side of the intermediate part and the near part, the side view in the intermediate part and the near part is comfortable, and the wearing feeling is excellent. A progressive power lens can be provided.

  A typical method for obtaining the distribution of only the front view is to obtain the distribution when the lines of sight of the left and right eyes are on the nose side of the vertical reference line passing through the fitting point.

  In addition, the step of obtaining the clear vision width specifications statistically processes each distribution to determine the clear vision width of the distance portion, the clear vision width of the intermediate portion, and the clear vision width of the near portion of the clear vision width specification. It is desirable to include seeking.

  In addition, designing a progressive power lens has a common basic specification including addition, and a plurality of specifications including a plurality of designed specifications of a progressive power lens designed based on spectacles specifications with different clear vision width specifications. Among the candidate specifications, the candidate specification that is closest to the clear vision width specification in the search space that includes the clear vision width of the distance portion, the clear vision width of the intermediate portion, and the clear vision width of the near portion as coordinate axes. It is desirable to include searching. Even in the case where a progressive power lens satisfying the basic specifications cannot be designed with the clear vision width of the distance view, intermediate portion and near view portion included in the clear view width specification, the distance view portion, intermediate portion and near view portion It is possible to provide a progressive-power lens in which the clear visual range of the wearer is ensured to the maximum and the wearer's line-of-sight movement is ensured to the maximum.

  The step of searching for candidate specifications includes generating a plurality of candidate specifications including a designable specification interpolated from at least a part of the plurality of designed specifications, and converting the plurality of candidate specifications into a clear vision width specification. Including determining the closest candidate specification and designing a progressive addition lens based on the determined candidate specification. Candidate specifications interpolated from designed specifications (design data) can be included in the candidate specifications as designable specifications, and candidate specifications closer to the clear vision width specifications can be obtained. Therefore, it is possible to design and provide a progressive-power lens that is more difficult to prevent the wearer from moving the line of sight.

  In this design method, a candidate specification to be searched includes a designable specification in addition to a designed specification. Therefore, it is desirable to actually design the progressive-power lens with the candidate specification obtained by the search and confirm the performance.

  One method for generating a plurality of candidate specifications including a designable specification is to place a specification selectable surface including at least a part of the plurality of designed specifications in the search space. In the step of obtaining the candidate specification, the point on the specification selectable surface that is closest to the clear vision width specification can be selected as the obtained candidate specification. By forming a selectable surface in the search space, it is possible to provide candidate specifications that are closer to the clear vision width specifications.

  Another different aspect of the present invention is a method for manufacturing a progressive-power lens, which includes manufacturing a progressive-power lens designed by the above-described design method.

  Another aspect of the present invention is a progressive-power lens for spectacles having a distance portion and a near portion having different visual powers, and an intermediate portion located between the distance portion and the near portion. It is an apparatus including a unit for designing. The designed unit is the clear vision width of the wearer including the clear vision width of the distance portion, the clear vision width of the intermediate portion, and the clear vision width of the near portion, suitable for the wearer's distance vision, intermediate vision and near vision. A function or means for acquiring the specifications (clear vision width specification acquisition unit) and a function or means for designing individual progressive-power lenses (individual design unit) based on spectacles specifications including the clear vision width specifications . Furthermore, the function of obtaining the clear vision width specification is based on the direction of the wearer's line of sight and / or movement of the head, from the clear vision width of the distance portion, the clear vision width of the intermediate portion, and the clear vision width of the near portion When obtaining the corresponding far vision, intermediate vision, and near vision distributions, the distribution of far vision, including side vision and front vision, is obtained, and for intermediate vision and near vision, only the front vision distribution is obtained. Including a function for obtaining (distribution acquisition unit).

  As for the function for obtaining the distribution, it is desirable to obtain the distribution when the line of sight of both the left and right eyes is on the nose side with respect to the vertical reference line passing through the fitting point when obtaining the distribution of only the front view. In addition, the function for obtaining the clear vision width specification statistically processes each distribution to obtain the clear vision width of the distance portion, the clear vision width of the intermediate portion, and the clear vision width of the near portion of the clear vision width specification. It is desirable.

  In addition, the function to design each progressive power lens includes a plurality of pre-designed specifications of progressive power lenses designed based on spectacles specifications based on common specs including add power and different clear vision width specifications. Among the multiple candidate specifications, the distance from the clear vision width specification is the shortest in the search space including the clear vision width of the distance portion, the clear vision width of the intermediate portion, and the clear vision width of the near portion as coordinate axes. It is effective to include a function (search unit) for searching for candidate specifications.

  With this device, it is possible to design a progressive-power lens that satisfies the basic specification with the specification closest to the clear vision width specification. Therefore, it is a progressive-power lens that satisfies the basic specifications, and has a clear vision width that is wide enough so that it does not obstruct the gaze movement of the wearer (user) in far vision, intermediate vision, and near vision. It is possible to design and provide a progressive power lens provided in the use part, the intermediate part, and the near use part.

  Moreover, it is desirable that the apparatus has a unit for simulating the state viewed through the progressive-power lens designed by the design unit. Sales can be promoted by showing the wearer an image seen through the progressive-power lens designed by the above method.

The perspective view which shows an example of spectacles. FIG. 2A is a plan view schematically showing one of the progressive-power lenses, and FIG. 2B is a cross-sectional view thereof. The flowchart which shows the design and manufacturing method of the progressive-power lens which concerns on this invention. FIG. 4A is a diagram showing a distance vision distribution, FIG. 4B is a diagram showing an intermediate vision distribution, and FIG. 4C is a diagram showing a near vision distribution. The figure which shows the distribution of the far vision of the left eye. The figure which shows distribution of intermediate vision of the left eye. The figure which shows distribution of the near vision of the left eye. The figure which shows distribution of far vision of the right eye. The figure which shows distribution of intermediate vision of the right eye. The figure which shows distribution of the near vision of the right eye. The figure which shows a mode that the clear vision width of a distance part is calculated | required from distribution of a far vision. The figure which shows the relationship of both eyes of distance vision. The figure which shows the relationship of both eyes of intermediate vision. The figure which shows the relationship of both eyes of near vision. The figure which shows distribution of the front view in the intermediate vision of the left eye. The figure which shows distribution of the front view in the near vision of the left eye. The figure which shows distribution of the front view in the intermediate vision of the right eye. The figure which shows distribution of the front view in the near vision of the right eye. The flowchart which shows the method of designing a progressive-power lens individually. The figure which shows a mode that the clear vision width of a distance part, the clear vision width of an intermediate part, and the clear vision width of a near part are set. The figure which shows the state which connected the distance part and the near part smoothly. 6 is a flowchart illustrating different methods of designing a progressive power lens. The figure which shows the state which has arrange | positioned the candidate specification in search space. The figure which shows the state which has arrange | positioned the specification selection possible surface in search space. The block diagram which shows schematic structure of a design apparatus.

  FIG. 1 is a perspective view showing an example of eyeglasses. FIG. 2A schematically shows one lens of one progressive-power lens according to the embodiment of the present invention in a plan view. FIG. 2B schematically shows one of the progressive-power lenses in a cross-sectional view.

  In this example, as viewed from the user side (wearer side, wearer side, eyeball side), the left side is described as left and the right side is described as right. The spectacles 1 includes a pair of left and right spectacle lenses 10L and 10R for the left eye and right eye, and a spectacle frame 20 on which the lenses 10L and 10R are respectively mounted. The spectacle lenses 10L and 10R are progressive multifocal lenses (progressive power lenses), respectively. The basic shape of the lenses 10L and 10R is a meniscus lens convex on the object side. Therefore, each of the lenses 10L and 10R includes an object-side surface (hereinafter also referred to as an outer surface) 19A and an eyeball-side surface (hereinafter also referred to as an inner surface) 19B.

  FIG. 2A shows the right-eye lens 10R. This lens 10R includes a distance portion 11 that is a visual field portion for viewing an object at a long distance upward (for far vision), and a short distance with a different power (visual power, refractive power) from the distance portion 11 below. The near vision part 12 which is a visual field part for seeing the object (near vision) is included. Furthermore, the lens 10R includes an intermediate portion (a portion for intermediate vision, a progressive portion, a progressive zone) 13 that connects the distance portion 11 and the near portion 12 so that the visual power (refractive power) changes. . The lens 10 </ b> R includes a main gaze line 14 that connects a position on the lens that is the center of the field of view when performing far vision, intermediate vision, and near vision. In the spectacle lens 10 </ b> R, the fitting point FP, which is a reference point on the lens when the outer periphery is shaped and framed in accordance with the frame, is located substantially at the lower end of the distance portion 11.

  Hereinafter, the fitting point FP is set as the coordinate origin of the lens, the horizontal coordinate of the horizontal reference line X passing through the fitting point FP is set as the x coordinate, and the coordinate on the main gazing line 14 is set as the y coordinate. The main gaze line 14 bends to the nose side after passing the fitting point FP with respect to the vertical reference line (main meridian) Y passing through the fitting point FP. An interval between the main gaze line 14 and the vertical reference line Y is referred to as an inward amount. However, in the progressive-power lens of the present invention, for the intermediate vision and the near vision, the inward amount is defined by setting the position of the clear vision width from the vertical reference line y to the nose side from the distribution of only the front vision. Can be omitted. In the following description, the right-eye and left-eye spectacle lenses 10R and 10L are commonly referred to as spectacle lenses (or lenses) 10.

  FIG. 3 is a flowchart showing a process of designing and manufacturing a progressive power lens. The design of the progressive-power lens of this example is such that the clear vision width w1 of the distance portion 11, the clear vision width w2 of the intermediate portion 13 and the brightness of the near portion suitable for the wearer's distance vision, intermediate vision, and near vision. A step 100 for obtaining a spectacle width specification (clear vision width specification) W (w1, w2, w3) of the wearer including the viewing width w3, and a spectacle including the basic specification including the addition Add and the clear vision width specification W. Designing 300 an individual progressive power lens based on the specification.

  The step 100 for obtaining the clear vision width specification W includes a step 101 for obtaining a distant vision distribution, an intermediate vision distribution, and a near vision distribution from the wearer's gaze direction and / or head movement, and a far vision distribution. Then, the distribution of the intermediate vision and the distribution of the near vision are statistically processed to obtain the clear vision width w1 of the distance portion of the clear vision width specification W, the clear vision width w2 of the intermediate portion, and the clear vision width w3 of the near vision portion. Step 102 is included.

  The step 101 for obtaining the distribution of far vision, intermediate vision, and near vision further includes the step 105 for obtaining the distribution of side vision and front vision for the distribution of far vision, and the distribution of only the front vision for intermediate vision. Step 106 for obtaining, and Step 107 for obtaining the distribution of only the front view for near vision are also included.

  FIG. 4 shows an example of obtaining the distance vision distribution, the intermediate vision distribution, and the near vision distribution in step 101. FIG. 4A shows a method for measuring the distribution of far vision. In this method, a single-focus lens 31 having a refractive power for distance is prepared, and the wearer (wearer, user) performs far vision in a state where the lower side from the fitting point FP is covered with a shield 39, and the line-of-sight direction is determined. Measure multiple times. Gaze direction can be measured with an eye mark recorder. In addition, when the movement of the head is accompanied, the line-of-sight direction can be measured by measuring the rotation angle of the head.

  FIG. 4B shows a method for measuring the distribution of intermediate vision. In this method, a single focus lens 32 having a refractive power obtained by adding ½ of the addition power to the distance power is prepared, and the upper half of the fitting point FP and the lower side of the progressive zone length from the fitting point FP. The wearer (wearer, user) performs intermediate vision in a state of being covered with the shield 39 so as not to be seen, and the line-of-sight direction is measured a plurality of times.

  FIG. 4C shows a method of measuring the near vision distribution. In this method, a single focus lens 33 having a refractive power for near use is prepared, and the wearer is subjected to near vision while being covered with a shield 39 so as to be visible from the fitting point FP except for the portion below the progressive zone length. And measure the gaze direction multiple times.

  The line-of-sight direction includes the one that measures the average of both eyes with a measuring device and the one that measures the left and right directions. In addition, when it is difficult to shield the lens due to the arrangement of the measuring device, the lens may not be shielded, and data of the gaze direction corresponding to far vision, intermediate vision, and near vision may be acquired from the vertical direction of the gaze. In addition, a progressive power lens may be used in place of the single focus lens, and the distance in the line of sight may be determined from the direction of the line of sight of both eyes. May be limited.

  The degree to which the head or eyes are rotated when looking at an object varies depending on the wearer. In addition, since the lens has a prism action, the object can be seen in a direction different from the actual direction of the object. Therefore, there is a difference between the visual action with the naked eye and the visual action when the lens is worn, but with the above method, the gaze direction distribution according to the visual action when the wearer (subject) wears the lens Is obtained.

  FIG. 5 shows an example of the distribution of the line-of-sight direction for far vision of the left eye. FIG. 6 shows an example of the gaze direction distribution of the intermediate vision of the left eye. FIG. 7 shows an example of the distribution of the gaze direction of the near vision of the left eye. FIG. 8 shows an example of the distribution of the line-of-sight direction for far vision of the right eye. FIG. 9 shows an example of the distribution in the line-of-sight direction for intermediate vision of the right eye. FIG. 10 shows an example of the distribution of the gaze direction in the near vision of the right eye. In these drawings, the vertical axis represents frequency, and the horizontal axis represents the horizontal angle from the vertical reference line y.

In step 102, the far vision distribution, the intermediate vision distribution, and the near vision distribution are statistically processed to perform the clear vision width w1, the clear vision width w2 of the intermediate portion, and the near vision portion of the provisional specification W. The clear vision width w3 is obtained. As shown in FIG. 11, taking distance vision as an example, if distances l1 and l2 between eyeball 2 and lens 31 are known, horizontal clear vision widths wf1 and wf2 from vertical reference line Y are calculated as follows. it can.
wf1 = l1 tan (wfa1) (1)
wf2 = l2tan (wfa2) (2)
w1 = wf1 + wf2 (3)

  Specifically, the measurement result of the distribution of the line-of-sight direction for far vision of the left eye shown in FIG. 5 has an average of −0.476 degrees and a standard deviation σ of 13.0. Using this average value and standard deviation σ, the distribution in the line-of-sight direction for distance vision is approximated to a normal distribution, and angles wfa1 and wfa2 at which the frequency ρ is 0.05 are obtained. In this example, the angles wfa1 and wfa2 are -21.9 degrees and 21.0 degrees, and the clear vision widths wf1 and wf2 for far vision are 10.0 mm and 9.6 mm. Therefore, both ends of the clear vision width for far vision are (-10.0, 9.6) if defined by the coordinates in the horizontal direction (x direction), and the clear vision width w1 is 19.7 mm. However, the distances l1 and l2 are 25 mm, and the same applies to the following.

  The measurement result of the distribution of the gaze direction of the intermediate vision of the left eye shown in FIG. 6 has an average of 3.83 degrees and a standard deviation σ of 7.62. Using the average value and the standard deviation σ, the distribution in the line-of-sight direction of intermediate vision is approximated to a normal distribution, and angles wma1 and wma2 at which the frequency ρ is 0.05 are obtained. In this example, the angles wma1 and wma2 are −8.70 degrees and 16.4 degrees, and the clear vision widths wm1 and wm2 for intermediate vision are 3.8 mm and 7.3 mm. Accordingly, both ends of the clear vision width of the intermediate vision are (−3.8, 7.3) if defined by the coordinates in the horizontal direction (x direction), and the clear vision width w2 is 11.1 mm.

  The measurement results of the distribution of the gaze direction of the near vision of the left eye shown in FIG. 7 are 7.07 degrees on the average and 7.06 on the standard deviation σ. Using this average value and standard deviation σ, the near-sight line-of-sight direction distribution is approximated to a normal distribution, and angles wna1 and wna2 at which the frequency ρ is 0.05 are obtained. In this example, the angles wna1 and wna2 are -4.54 degrees and 18.7 degrees, and the near vision clear vision widths wn1 and wn2 are 2.0 mm and 8.5 mm. Therefore, both ends of the clear vision width for near vision are (−2.0, 8.5) if defined by the coordinates in the horizontal direction (x direction), and the clear vision width w3 is 10.5 mm.

  Similarly, the measurement result of the distribution in the gaze direction of the right eye far vision shown in FIG. 8 has an average of −1.47 degrees and a standard deviation σ of 14.9. Using this average value and standard deviation σ, the distribution in the line-of-sight direction for distance vision is approximated to a normal distribution, and angles wfa1 and wfa2 at which the frequency ρ is 0.05 are obtained. In this example, the angles wfa1 and wfa2 are −26.1 degrees and 23.1 degrees, and the clear vision widths wf1 and wf2 for far vision are 12.2 mm and 10.7 mm. Therefore, both ends of the clear vision width for far vision are (−12.2, 10.7) if defined by the coordinates in the horizontal direction (x direction), and the clear vision width w1 is 22.9 mm.

  The measurement results of the gaze direction distribution of the intermediate vision of the right eye shown in FIG. 9 have an average of −1.94 degrees and a standard deviation σ of 7.69. Using the average value and the standard deviation σ, the distribution in the line-of-sight direction of intermediate vision is approximated to a normal distribution, and angles wma1 and wma2 at which the frequency ρ is 0.05 are obtained. In this example, the angles wma1 and wma2 are -14.6 degrees and 10.7 degrees, and the clear vision widths wm1 and wm2 for intermediate vision are 6.5 mm and 4.7 mm. Therefore, both ends of the clear vision width of the intermediate vision are (−6.5, 4.7) if defined by the coordinates in the horizontal direction (x direction), and the clear vision width w2 is 12.2 mm.

  In the measurement result of the gaze direction distribution of the near vision of the right eye shown in FIG. 10, the average is −2.51 degrees and the standard deviation σ is 7.25. Using this average value and standard deviation σ, the near-sight line-of-sight direction distribution is approximated to a normal distribution, and angles wna1 and wna2 at which the frequency ρ is 0.05 are obtained. In this example, the angles wna1 and wna2 are -14.4 degrees and 9.41 degrees, and the clear vision widths wn1 and wn2 for near vision are 6.4 mm and 4.1 mm. Therefore, both ends of the near vision clear vision width are (−6.4, 4.1) if defined in the horizontal direction (x direction) coordinates, and the clear vision width w3 is 10.5 mm.

  From the above, the clear vision width specification Wl (19.7, 11.1, 10.5) of the left-eye lens and the clear vision width specification Wr (22.9, 12.2, 10.5) of the right-eye lens. ) Is obtained.

  Therefore, it is conceivable to provide and design the progressive power lens 10 that satisfies these clear vision width specifications Wl and Wr individually. However, according to Minkwitz's law, astigmatism 0.50 (D) in a progressive power lens including an addition power of 2.00 and a progressive length of 16 mm (power gradient 0.125 (D / mm)) as basic specifications The clear vision width of the following intermediate portion 13 is about 4 mm, and it is difficult to design a progressive power lens that satisfies the clear vision width specifications Wl and Wr. In addition, even if the design can be made, the side view of the intermediate portion and the side view of the near portion are reflected in the clear vision width specifications Wl and Wr. Deterioration of the lens performance on the side of the portion and the near portion becomes large.

  FIG. 12 plots the line-of-sight directions of the left eye and the right eye measured in far vision. FIG. 13 plots the gaze directions of the left eye and the right eye measured in the intermediate vision. FIG. 14 plots the line-of-sight directions of the left eye and the right eye measured in near vision. Assuming that the right and left eyes are on the nose side of the vertical reference line y passing through the fitting point, the right side view is plotted in the first quadrant and the left side view in the third quadrant. Is plotted, and it is considered that the front view is plotted in the fourth quadrant. Usually, it is not plotted in the second quadrant. The intermediate portion 13 and the near portion 12 of the progressive-power lens 10 are basically used for obtaining a comfortable front view.

  Therefore, in step 101 for obtaining the clear vision width specification shown in FIG. 3, in step 105, the clear vision width including the front view and the side view is assigned as the clear vision width w1 of the distance portion 11, and step 106 is performed. In Step 107, the clear vision width of only the front view is assigned as the clear vision width w2 of the intermediate portion 13. In Step 107, the clear vision width of only the front view is assigned as the clear vision width w3 of the near vision portion 12. Therefore, in the following, in order to obtain the clear vision width w2 of the intermediate portion 13 and the clear vision width w3 of the near portion 12, only the distribution of the measurement data in the fourth quadrant of FIGS. 13 and 14 is acquired. That is, the distribution when the line of sight of the left and right eyes is on the nose side with respect to the vertical reference line y passing through the fitting point FP is obtained.

  FIG. 15 shows a front view distribution in the intermediate vision of the left eye. FIG. 16 shows a front view distribution in the near vision of the left eye. FIG. 17 shows a distribution of front view in intermediate vision of the right eye. FIG. 18 shows the distribution of front view in the near vision of the right eye.

  The measurement result of the gaze direction distribution in front of the intermediate vision of the left eye shown in FIG. 15 has an average of 3.31 degrees and a standard deviation σ of 2.18. Using the average value and the standard deviation σ, the distribution in the line-of-sight direction of intermediate vision is approximated to a normal distribution, and angles wma1 and wma2 at which the frequency ρ is 0.05 are obtained. In this example, the angles wma1 and wma2 are −0.28 degrees and 6.90 degrees, and the clear vision widths wm1 and wm2 for intermediate vision are 0.1 mm and 3.0 mm. Therefore, both ends of the clear vision width of the intermediate vision are (−0.1, 3.0) if defined by the coordinates in the horizontal direction (x direction), and the clear vision width w2 is 3.5 mm. In addition, the position of 1.4 mm at the average value of 3.31 degrees corresponds to the inset amount d of the left-eye middle portion 13.

  The measurement result of the gaze direction distribution of the near vision of the left eye shown in FIG. 16 has an average of 5.44 degrees and a standard deviation σ of 3.23. Using this average value and standard deviation σ, the near-sight line-of-sight direction distribution is approximated to a normal distribution, and angles wna1 and wna2 at which the frequency ρ is 0.05 are obtained. In this example, the angles wna1 and wna2 are 0.12 degrees and 10.8 degrees, and the near vision clear vision widths wn1 and wn2 are 0.1 mm and 4.8 mm. Therefore, both ends of the clear vision width for near vision are (0.1, 4.8) if defined by the coordinates in the horizontal direction (x direction), and the clear vision width w3 is 4.7 mm. Note that the position of 2.4 mm at an average value of 5.44 degrees corresponds to the inward amount d of the near-eye portion 12 of the left eye.

  The measurement result of the gaze direction distribution in front of the right-eye intermediate vision shown in FIG. 17 has an average of −3.16 degrees and a standard deviation σ of 2.54. Using the average value and the standard deviation σ, the distribution in the line-of-sight direction of intermediate vision is approximated to a normal distribution, and angles wma1 and wma2 at which the frequency ρ is 0.05 are obtained. In this example, the angles wma1 and wma2 are −7.34 degrees and 1.02 degrees, and the clear vision widths wm1 and wm2 for intermediate vision are 3.2 mm and 0.4 mm. Accordingly, both ends of the clear vision width of the intermediate vision are (−3.2, 0.4) if defined by the coordinates in the horizontal direction (x direction), and the clear vision width w2 is 3.6 mm. Note that an average value of −3.16 degrees at a position of −1.4 mm corresponds to the inward amount d of the middle portion 13 of the right eye.

  The measurement result of the gaze direction distribution in front of the near vision of the right eye shown in FIG. 18 has an average of −4.53 degrees and a standard deviation σ of 2.97. Using this average value and standard deviation σ, the near-sight line-of-sight direction distribution is approximated to a normal distribution, and angles wna1 and wna2 at which the frequency ρ is 0.05 are obtained. In this example, the angles wna1 and wna2 are −9.42 degrees and 0.36 degrees, and the near vision clear vision widths wn1 and wn2 are 4.1 mm and 0.2 mm. Therefore, both ends of the clear vision width for near vision are (−4.1, 0.2) if defined by the coordinates in the horizontal direction (x direction), and the clear vision width w3 is 4.3 mm. The average value −4.53 ° position −2.0 mm corresponds to the inward amount d of the near-eye portion 12 of the right eye including side view.

  As described above, in step 102, the left eye clear vision width specification W1 (19.7, 3.5, 4.7) and the right eye clear vision width specification Wr (22.9, 3.6, 4.3). ) Is obtained. Also, a specification dl (1.4, 2.4) for the left eye inset amount and a specification dr (-1.4, -2.0) for the right eye inset amount are obtained. These clear vision width specifications Wl and Wr are values with which a progressive-power lens can be sufficiently designed even in consideration of Minkwitz's law.

  Accordingly, in step 300, left and right individual progressive addition lenses are designed. FIG. 19 shows an example of a design procedure for a progressive-power lens that can be employed in step 300. In step 304, basic specifications are set. The basic specifications include a progressive power lens substrate, outer surface progression or inner surface progression, prescription power (distance power (Sph), addition power (Add), astigmatism power (C), astigmatism axis (Ax))), progressive zone Length, position of progressive zone length, position of clear vision width of distance portion 11, position of clear vision width of intermediate portion 13, position of clear vision width of near portion 12, astigmatism of clear vision width, side The maximum astigmatism of.

In the following, the basic specifications are set as follows.
1) A progressive power lens “Seiko Super P-1” A type (refractive index of 1.67) manufactured by Seiko Epson Corporation is used as the base material.
2) The inner surface refractive power lens has a spherical outer surface 19A and a progressive surface on the inner surface 19B.
3) The distance power (Sph) of the prescription power (visual power) is 0.00 (D), the addition power (Add) is 1.50 (D), the astigmatism power (C) is 0.00 (D), The astigmatic axis (Ax) is not provided.
4) The progressive zone length is 16 mm, and the position of the progressive zone length starts from the fitting point FP.
5) The position of the clear vision width of the distance portion 11 is 3 mm above the fitting point FP, and the clear vision width position of the intermediate portion 13 is 7 mm below the fitting point FP (that is, the center of the progressive zone). The position of the clear vision width is 17 mm below the fitting point FP (that is, 3 mm below the end point of the progressive zone).
6) The maximum astigmatism of clear vision width is 0.50 (D) at the maximum, and the lateral maximum astigmatism is 1.50 (D).

  After setting the basic specifications, in step 305, the clear vision width w1 of the distance portion 11, the clear vision width w2 of the intermediate portion 13, and the clear vision width w3 of the near portion 12 are set. In this design method, since the clear vision widths w2 and w3 are obtained as a front view, the amount of inset is defined by setting the positions of the clear vision widths w2 and w3 from the vertical reference line y to the nose side. Can be omitted. The clear vision widths w2 and w3 of the intermediate portion 13 and the near portion 12 may be set by length or may be set by coordinates. The same applies to the clear vision width w1 of the distance portion 11.

  In this example, as shown in FIG. 20, the spherical surface of the distance power is set in an arc shape in a range 41 corresponding to the clear vision width w1 of the distance portion 11, and corresponds to the clear vision width w3 of the near vision portion 12. A spherical surface having a near power is set in an arc shape in a range 42 to be used. Note that the method of setting the spherical surface range is not limited to the arc shape, and it suffices that the entire range set for the clear viewing width is included in the spherical surface range.

  Next, in step 306, the distance spherical range 41 and the near spherical range 42 are smoothly connected. In step 307, as shown in FIG. 21, the width of the isoline 45 of astigmatism 0.50D is compared with the clear vision widths w1, w2, and w3, and the clear vision width as intended is obtained. Confirm whether or not. In FIG. 21, the clear vision width w2 of the intermediate portion 13 cannot be secured. In such a case, the process returns to step 305, and after slightly reducing the arc angles of the range 41 of the distance portion 11 and the range 42 of the near portion 12, step 306 is repeated again. When the design satisfying the set clear vision widths w1, w2, and w3 is completed in this way, in step 308, the designed specifications that satisfy the clear vision widths w1, w2, and w3 are output.

  If an appropriate progressive-power lens can be designed in step 300 by these steps, as shown in the flowchart of FIG. 3, then in step 500, the progressive-power lens 10 for spectacles having the designed inner and outer surfaces is used. Manufacturing.

  As described above, the progressive addition lens can be designed and manufactured so that a comfortable front view can be obtained in the clear viewing width of the intermediate portion 13 and the near portion 12. By limiting the clear vision widths w2 and w3 of the intermediate portion 13 and the near vision portion 12 to the range of the front view, the clear vision widths w2 and w3 included in the clear vision width specification W when the progressive power lens 10 is designed. Can be reduced. As a result, it is possible to obtain a clear vision width specification W having clear vision widths w1 to w3 that can sufficiently design a progressive-power lens even in consideration of the Minkwitz law, and the intermediate portion 13 and the near portion 12 side. On the other hand, it is possible to provide the progressive-power lens 10 in which the lens performance is not extremely deteriorated, that is, the spherical aberration is relatively small. Therefore, the clear vision width w2 of the intermediate portion 13 and the clear vision width w3 of the near vision portion 12 included in the clear vision width specification W of the design are values considering only the front view, but based on the clear vision width specification W. In the progressive-power lens 10 designed and manufactured in this way, the progressive-power lens 10 having a relatively small image distortion in a side view as well as a front view can be provided.

  FIG. 22 is a flowchart showing a different method for designing and manufacturing the progressive-power lens 10. This progressive-power lens design method is also suitable for the wearer's distance vision, intermediate vision, and near vision, the clear vision width w1 of the distance portion 11, the clear vision width w2 of the intermediate portion 13, and the clear vision of the near portion. A step 100 for obtaining a clear vision width specification (clear vision width specification) W (w1, w2, w3) of the wearer including the width w3, and a spectacle specification including the basic specification including the addition degree Add and the clear vision width specification W. And designing an individual progressive power lens based on Further, the step 100 for obtaining the clear vision width specification W is common to the design method shown in FIG.

  Step 300 for designing individual progressive-power lenses of this design method uses a search space having the clear vision width specification W obtained in step 100 as a provisional specification and the clear vision widths w1, w2 and w3 as coordinate axes, respectively. A progressive-power lens that is suitable for the wearer's clear vision width specification W and that prevents the movement of the line of sight as much as possible is designed. That is, the step 300 for designing a progressive power lens includes a plurality of designed specifications of a progressive power lens designed based on spectacles specifications that are common in basic specifications including addition Add and that have different clear vision width specifications. Among the plurality of candidate specifications Si (s1i, s2i, s3i), the clear vision width of the distance portion 11, the clear vision width of the intermediate portion 13, and the clear vision width of the near portion 12 are included as coordinate axes X, Y, and Z. In the search space, a step 200 for searching for candidate specifications Si (s1i, s2i, s3i) having the shortest distance D from the provisional specifications using the clear vision width specifications W (w1, w2, w3) as the temporary specifications is included. . However, i is an integer from 1 to n, and the i-th candidate specification Si includes the clear vision width s1i of the distance portion 11, the clear vision width s2i of the intermediate portion 13, and the clear vision width s3i of the near portion.

  In step 300 of designing the progressive-power lens, candidate specifications Si to be searched are acquired simultaneously with or before or after step 100 of acquiring the clear vision width specification W. First, in step 301, it is determined whether or not it is necessary to newly design a progressive power lens to be searched. If it is necessary to newly design, a progressive power lens having appropriate clear vision widths s1, s2, and s3 is designed based on the spectacle specifications having the same basic specifications in Step 302, and the designed specifications are generated as candidate specifications S. To do. If the existing design can be used, the specification of the existing progressive-power lens is selected as the candidate specification S in step 303. It is also possible to include the existing design specification and the newly designed specification in the candidate specification S. In step 302 of newly designing the progressive-power lens, the design method described with reference to FIG. 19 can be employed. For example, in step 308 of the design method of FIG. 19, the design specification FSi that satisfies the clear vision widths s1, s2, and s3 is output. The existing design of step 303 shown in the flowchart of FIG. 22 is also a designed specification FSi that satisfies the clear vision widths s1i, s2i, and s3i.

  The step 200 for searching for candidate specifications Si includes a step 201 for arranging (mapping) a plurality of candidate specifications Si in the search space, and a candidate specification Si closest to the clear vision width specification W among the mapped candidate specifications Si. And step 202 of searching.

  The step 201 for arranging candidate specifications Si in the search space further includes a step 203 for determining whether or not to increase the number of candidate specifications Si by interpolation from the designed specifications FSi and a candidate by interpolation from the designed specifications FSi. Generating a specification Si. The specification generated by interpolation from the designed specification FSi is a specification ASi that is assumed to be designable. However, even if it is a designable specification ASi, the progressive surface is not actually designed with the designable specification ASi. Therefore, as will be described later, when searching including candidate specifications Si including designable specifications ASi, it is necessary to actually design a progressive surface using the searched candidate specifications Si. Examples of the interpolation method for obtaining the design ASi that can be designed from the designed specification FSi include the least square method and the bicubic spline method.

  When a plurality of candidate specifications Si to be searched are selected or generated, in step 205, the candidate specifications Si are mapped to the search space. One of the methods for mapping the shortest candidate specification Si to the specification W is to obtain a surface (specification selectable surface) Q in the search space including the specification FSi designed in step 204 by the least square method or the like. The specification selectable surface Q is set (mapped) in the search space.

FIG. 23 shows several candidate specifications S1 in a search space 50 including the clear vision width of the distance portion 11 as the X axis, the clear vision width of the intermediate portion 13 as the Y axis, and the clear vision width of the near portion 12 as the Z axis. This shows the mapping of ~ S5. In the search space 50, candidate specifications Si having the clear vision widths s1i, s2i, and s3i of the distance portion 11, the intermediate portion 13, and the near portion 12, and the distance portion 11, the intermediate portion 13, and the near portion 12 The distance D from the specification W having the respective clear vision widths w1, w2, and w3 is obtained by the following expression (4).
D = √ ((w1−s1i) ² + (w2−s2i) ² + (w3−s3i) ² ) (4)

  Therefore, in FIG. 23, candidate specification S5 is searched in step 202 for searching for candidate specification Si closest to provisional specification W. If the candidate specification S5 is a designed specification FS, the progressive addition lens 10 having the clear vision widths s15, s25 and s35 of the distance portion 11, the intermediate portion 13 and the near portion 12 of the candidate specification S5 is The progressive power lens 10 that can be manufactured and has a clear vision width closest to the specification W can be provided.

  FIG. 24 shows a state in which the surface Q whose specifications can be selected is mapped to the search space 50. The surface Q may be a flat surface or a curved surface. In this example, the progressive addition lens 10 has the same basic specifications 1) to 6) described above, and the clear vision widths s1i, s2i, and s3i of the distance portion 11, the intermediate portion 13, and the near portion 12, respectively. A plurality of designed candidate specifications Si, each of which is different from each other, are generated and interpolated by the least square method to obtain a point at each coordinate of the surface Q whose specifications can be selected.

  In FIG. 24, the candidate specification whose point SP on the specification selectable surface Q closest to the specification W is closest to the specification W is obtained in step 206 for obtaining the distance from the specification selectable surface Q in step 202 for searching for the candidate specification Si. Selected as Si. When the candidate specification Si closest to the specification W (the shortest distance) is obtained in the search space 50 in step 202, it is determined in step 401 whether or not the progressive power lens 10 is designed based on the obtained candidate specification Si. to decide. If the candidate specification Si arranged in the search space 50 is a designed specification FSi, the progressive addition lens 10 can be manufactured with the obtained candidate specification Si because it has already been designed.

  On the other hand, if the candidate specification Si arranged in the search space 50 includes the designable specification ASi interpolated, the progression that includes the clear vision widths s1i, s2i, and s3i included in the candidate specification Si and satisfies the basic specification There is a possibility that the refractive power lens 10 cannot be designed. Therefore, in step 402, the progressive-power lens 10 is designed based on the obtained candidate specification Si. As a method of designing the progressive-power lens 10 in Step 402, the method described based on FIG. 19, that is, the same method as Step 302 can be employed.

  Next, in step 500, the progressive-power lens 10 for spectacles having the inner and outer surfaces designed as described above is manufactured.

  In the design and manufacturing method described above, in step 100, the distribution of far vision, intermediate vision, and near vision is obtained for each wearer, and clear vision of the distance portion 11, the intermediate portion 13, and the near vision portion 12 is obtained. A clear vision width specification W including the widths w1, w2, and w3 is acquired. In particular, in the clear vision widths w2 and w3 of the intermediate portion 13 and the near vision portion 12, clear vision widths w2 and w3 corresponding only to the front view are acquired. In step 200, a candidate specification Wi closest to the clear vision width specification W is searched, and an individual progressive power lens is designed based on the candidate specification Wi. Therefore, even if a combination of clear vision widths w1, w2, and w3 that cannot be provided as a progressive-power lens is included in the clear vision width specification W, it is as close as possible to the original clear vision width w1, w2, and w3. A progressive-power lens having a clear viewing width can be provided. Further, even if the clear vision widths w1, w2 and w3 included in the clear vision width specification W, especially the clear vision widths w2 and w3 are too limited, the original clear vision widths w1, w2 and w3 It is possible to provide a progressive addition lens having a maximum clear vision width close to the distance portion 11, the intermediate portion 13, and the near portion 12, which does not obstruct the natural line-of-sight movement of the wearer (wearer) as much as possible. A progressive power lens 10 with a clear viewing width can be designed and manufactured and provided to the wearer.

  FIG. 25 shows a schematic configuration of an example of a spectacle lens design apparatus 70. The design apparatus 70 is realized by a personal computer or other information processing apparatus having hardware resources normally included as a computer such as a CPU and a memory. The design device 70 includes a design unit 71 that designs a progressive-power lens 10 for spectacles having a distance portion 11, an intermediate portion 13, and a near-use portion 12, and a progressive-power lens for glasses that is designed by the design unit 71. 10L and 10R are units including a unit 80 that simulates the appearance of a wearer (user) looking through.

  The design unit 71 includes an acquisition unit (clear vision width specification acquisition unit) 72 having the function of performing the processing of step 100 for obtaining the above-described clear vision width specification W, and a candidate specification closest to the clear vision width specification W. A search unit 73 having a function of performing the process of step 200 for searching for Si, and an individual design unit 74 for specifically designing the progressive-power lens 10 based on spectacles specifications including basic specifications and clear vision width specifications W; A specification library 75 that stores individually designed specifications FSi and designable specifications ASi interpolated from the designed specifications FSi.

  The clear vision width specification acquisition unit 72 further corresponds to the clear vision width of the distance portion, the clear vision width of the intermediate portion, and the clear vision width of the near portion based on the direction of the line of sight of the wearer and / or movement of the head. Distribution of distance vision, intermediate vision, and near vision distribution for distance vision, lateral vision and front vision distribution, and intermediate vision and near vision distribution for front vision only It includes an acquisition unit 72a and a statistical processing unit 72b that statistically processes the obtained distribution to acquire the clear vision widths w1, w2, and w3 of the distance portion, the intermediate portion, and the near portion. In the distribution acquisition unit 72a, the process of step 101 described above is executed, and in the statistical processing unit 72b, the process of step 102 described above is executed.

  The search unit 73 further includes a candidate specification generating unit 76 for generating a plurality of candidate specifications Si including a designable specification ASi interpolated from at least a part of the plurality of designed specifications FSi, And a specification acquisition unit 77 for obtaining a candidate specification Si closest to the temporary specification W. Further, the candidate specification generation unit 76 includes a mapping unit 78 that maps the candidate specification Si to the search space 50. The mapping unit 78 arranges a plurality of generated candidate specifications Si as points in the search space 50, and maps a specification selectable surface Q including the plurality of candidate specifications Si to the search space 50 (specification selectable surfaces). The function to arrange) is also provided.

  In addition to the function of selecting the candidate specification Si closest to the temporary specification W from the candidate specifications Si mapped in the search space 50, the specification acquisition unit 77 can select the specification selectable surface Q closest to the temporary specification W. A specification selection unit 79 for selecting the upper point as the obtained candidate specification is included.

  In this design apparatus (design system) 70, each progressive power lens may be designed by the individual design unit 74 based on the clear vision width specification W obtained by the clear vision width specification acquisition unit 72. 73 may be used to design a progressive power lens.

  In the design device (design system) 70, the wearer (user) sees the designed spectacle lenses 10L and 10R through the simulation unit 80, and can be provided to the wearer. An example of the simulation unit 80 is an image display device, which allows a wearer to virtually experience a corrected visual acuity in which left and right clear vision widths are secured using a head mounted display or the like.

  By using this design device 70, the user has a sufficiently wide apparent width of the intermediate portion 13 and the near portion 12 at a spectacle store, and further, there is little deterioration in the performance of the side of the clear vision width, You can virtually experience a comfortable field of view that will not interfere with the movement of the wearer's line of sight.

  In the design method and the design apparatus 70 for the progressive-power lens 10 described above, as the search space 50, the clear vision width of the distance portion 11, the clear vision width of the intermediate portion 13, and the clear vision width of the near portion 12 are set. Although a three-dimensional space provided as coordinate axes has been described as an example, a four-dimensional or more space in which other elements are added as axes may be used.

  For example, in the above description, the clear vision widths w2 and w3 of the intermediate portion 13 and the near portion 12 are given by the width (distance) with respect to the vertical reference line y. There is no need to consider. On the other hand, as described above, when the clear vision widths w2 and w3 of the intermediate portion 13 and the near portion 12 are statistically processed, the left and right inward specifications dl and dr are obtained. Accordingly, the clear vision width of the distance portion 11 and the clear vision width of the intermediate portion 13 are determined using the four-dimensional search space 50 in which the insight specification d is included in the clear vision width specification W for each wearer and the inset amount is added to the coordinate axes. It is also possible to design, manufacture, and provide a progressive power lens in which the clear vision width, the clear vision width of the near portion 12 and the amount of inward alignment are suitable for the wearer.

  The specifications such as the basic specifications and the design data described above are merely examples for explaining the present invention, and the present invention is not limited to the above specifications and design data.

DESCRIPTION OF SYMBOLS 1 Glasses, 10, 10L, 10R Glasses lens 11 Distance part, 12 Near part, 13 Middle part (progressive part)
19A Object side surface, 19B Eyeball side surface 20 Frame

Claims (11)

A design method of a progressive-power lens for spectacles having a distance portion and a near portion having different visual powers, and an intermediate portion located between the distance portion and the near portion,
Specifications of the clear vision width of the wearer including the clear vision width of the distance portion, the clear vision width of the intermediate portion, and the clear vision width of the near portion suitable for the far vision, intermediate vision and near vision of the wearer And getting
Designing a progressive power lens based on spectacles specifications including the clear vision width specification,
Acquiring the specification of the clear vision width is based on the direction of the line of sight of the wearer and / or the movement of the head, from the clear vision width of the distance portion, the clear vision width of the intermediate portion, and the clearness of the near portion. Determining each distribution of distance vision, intermediate vision, and near vision corresponding to the visual range,
Obtaining each of the distributions is to obtain a distribution including a side view and a front view for the far vision distribution;
A method for designing a progressive-power lens, including obtaining a distribution of only a front view for the intermediate vision and the near vision. In claim 1,
The method for designing a progressive power lens, wherein obtaining the distribution of only the front view includes obtaining a distribution when the line of sight of both the left and right eyes is on the nose side of the vertical reference line passing through the fitting point. In claim 1 or 2,
The specification of the clear vision width is obtained by statistically processing each of the distributions so that the clear vision width of the distance portion, the clear vision width of the intermediate portion, and the near vision light of the clear vision width specification are obtained. A method for designing a progressive-power lens, including determining a viewing width. In any of claims 1 to 4,
Designing the progressive power lens includes a plurality of specifications including a plurality of designed specifications of a progressive power lens designed based on the spectacles specifications based on the spectacle specs having different basic vision specifications including the addition power. In the search space including the clear vision width of the distance portion, the clear vision width of the intermediate portion, and the clear vision width of the near portion as coordinate axes, the distance from the clear vision width specification A method for designing a progressive-power lens, including searching for the closest candidate specification. In claim 4,
Determining the distribution of only the front view includes determining the amount of inset,
The searching includes searching for a candidate specification that is closest in distance to the clear vision width specification further including the internalization amount in the search space further including the internalization amount as a coordinate axis. A method for designing a power lens.   A method for manufacturing a progressive-power lens, comprising manufacturing a progressive-power lens designed by the design method according to claim 1. An apparatus including a unit for designing a progressive-power lens for spectacles having a distance portion and a near portion having different visual powers, and an intermediate portion located between the distance portion and the near portion,
The unit to be designed includes the clear vision width of the distance portion, the clear vision width of the intermediate portion, and the clear vision width of the near portion, which are suitable for the far vision, intermediate vision, and near vision of the wearer. With the ability to get clear vision width specifications
A function of designing individual progressive-power lenses based on spectacles specifications including the clear vision width specifications,
The function of obtaining the specification of the clear vision width is based on the direction of the line of sight of the wearer and / or the movement of the head, from the clear vision width of the distance portion, the clear vision width of the intermediate portion, and the clearness of the near portion. When obtaining each distribution of far vision, intermediate vision, and near vision corresponding to the visual range, the distribution including far vision and front vision is obtained for the far vision distribution, and the intermediate vision and the near vision are obtained. Is a device that includes the function to obtain the distribution of only the front view. In claim 7,
The function for obtaining the distribution is an apparatus for obtaining a distribution when the line of sight of both the left and right eyes is located on the nasal side with respect to a vertical reference line passing through the fitting point when obtaining the distribution of only the front view. In claim 7 or 8,
The function of obtaining the clear vision width specification is a statistical process on the respective distributions, and the clear vision width of the distance portion, the clear vision width of the intermediate portion, and the near vision light of the clear vision width specification. A device that determines the visual range. In any of claims 7 to 9,
The function of designing the individual progressive-power lenses has a plurality of pre-designed specifications of the progressive-power lenses designed based on the spectacles specifications that are based on the spectacle specs that have the same basic specifications including the addition power and that have different clear vision width specifications. Among the plurality of candidate specifications including, in the search space including the clear vision width of the distance portion, the clear vision width of the intermediate portion, and the clear vision width of the near portion as coordinate axes, the clear vision width specification and A device including a function of searching for candidate specifications with the closest distance.   11. The apparatus according to claim 7, further comprising a unit that simulates a state viewed through a progressive-power lens designed by the unit to be designed.

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