Abstract: A reference lens common to left and right and reference object surface common to left and right including a plurality of object surfaces; calculating a ratio between distance from an intersection between a visual line in a front view and the reference lens to chief ray passing position on the reference lens and distance from an intersection between the visual line in the front view and the pseudo prescribed lens to the chief ray passing position on the pseudo prescribed lens; correcting, for each of the left and the right, a curvature distribution of pseudo prescribed lens' by correcting curvature at the chief ray passing position on the pseudo prescribed lens corresponding to each point on each of the plurality of object surfaces; and correcting, for each of the left and the right, curvature distribution of the prescribed lens based on the corrected curvature distribution of the pseudo prescribed lens.

Abstract: A pair of spectacle lenses includes: a first refractive portion; a second refractive portion whose refractive power is stronger than the first's; and a progressive power portion in which a refractive power changes progressively from the first to the second refractive portion, first refractive powers of a left and right of the lenses being different, progressive power portions lengths of the left and right of the lenses are different and changing rates of additions of the left and right of the lenses are different in accordance with a shift between left and right visual lines so that a difference between addition effects acting on the wearer's eyes is reduced when the left and right visual lines shift with respect to each other depending on the first refractive powers of the left and the right of the lenses being different where the wearer views an object through the lenses.

Abstract: An eyeglass lens, comprising: a hidden mark defining a predetermined reference point; and refractive portions arranged along a meridian extending substantially in a vertical direction via the predetermined reference point, and wherein the refractive portions comprises: a first refractive portion located on a lower side of the predetermined reference point and having a first refractive power; a second refractive portion located on an upper side of the predetermined reference point and having a second refractive power smaller than the first refractive power; and an intermediate refractive portion in which refractive power continuously decreases, and an aberration distribution in the first refractive portion is substantially symmetrical in a left and right direction with respect to the meridian extending in the vertical direction, and an aberration distribution in the second refractive portion is asymmetrical in the left and right direction with respect to the meridian shifted to an ear side.

Abstract: There is provided a spectacle lens, including: specific first and second reference points, and eye point between the first and second reference points on a meridian, with each point defined on a meridian; and a power variation portion where power is continuously varied from the first reference point to the second reference point, wherein a variation rate of an addition power is substantially zero in a circle of radius 4 mm with the first reference point as a center, and/or in a circle of radius 4 mm with the eye point as a center.

Abstract: A spectacle lens capable of obtaining a good vision without feeling of discomfort, even being fitted into a frame having a large front angle, and a method of creating the shape data of the spectacle lens having dioptric power to be fitted into a frame having a lens front angle. The method corrects the shape data of a lens back surface so that the prismatic effect undergone via the lens of initial lens shape by a plurality of rays passing through a rotation center of the eye in a case where a lens front angle is provided is identical or close to the prismatic effect undergone via the lens of initial lens shape by the plurality of rays passing through the rotation center of the eye in a case where no lens front angle is provided.

Abstract: A spectacle lens capable of obtaining a good vision without feeling of discomfort, even being fitted into a frame having a large front angle, and a method of creating the shape data of the spectacle lens having dioptric power to be fitted into a frame having a lens front angle. The method corrects the shape data of a lens back surface so that the prismatic effect undergone via the lens of initial lens shape by a plurality of rays passing through a rotation center of the eye in a case where a lens front angle is provided is identical or close to the prismatic effect undergone via the lens of initial lens shape by the plurality of rays passing through the rotation center of the eye in a case where no lens front angle is provided.

Abstract: An eyeglass lens, comprising: a hidden mark defining a predetermined reference point; and refractive portions arranged along a meridian extending substantially in a vertical direction via the predetermined reference point, and wherein the refractive portions comprises: a first refractive portion located on a lower side of the predetermined reference point and having a first refractive power; a second refractive portion located on an upper side of the predetermined reference point and having a second refractive power smaller than the first refractive power; and an intermediate refractive portion in which refractive power continuously decreases, and an aberration distribution in the first refractive portion is substantially symmetrical in a left and right direction with respect to the meridian extending in the vertical direction, and an aberration distribution in the second refractive portion is asymmetrical in the left and right direction with respect to the meridian shifted to an ear side.

Abstract: An evaluation method of a progressive-addition lens is provided. First, powers of the progressive-addition lens at a plurality of measurement points are measured to obtain an actually measured power distribution. Next, a comparison power distribution created based on the actually measured power distribution and a defective power distribution prepared in advance are compared with each other to perform similarity search between the both. Thereafter, whether or not the comparison power distribution and the defective power distribution are similar to each other is determined based on the result of the similarity search step, and if it is determined that the comparison power distribution and the defective power distribution are similar to each other, then the progressive-addition lens is evaluated as defective.

Abstract: In a progressive-addition lens having a progressive surface on one side and an aspherical or atoroidal surface on the other side, the lens shape is designed so that a high degree of aberration correction can be carried out on the periphery of the lens and the distance power and addition power of the lens acting on the eye of a wearer substantially correspond to the distance power and addition power measured by a lens meter. A progressive-addition lens includes a progressive surface and an aspherically designed surface formed of an aspherical or atoroidal surface, and the reference point of the aspherically designed surface is located in the vertical direction of the lens below a prism reference point of the progressive surface and above a near design reference point.

Abstract: The present invention is to provide a lens evaluation method capable of easily evaluating whether there is a difference which greatly changes locally in a lens, and evaluating the degree of the difference. According to the lens evaluation method of the present invention, first, power a distribution of a plurality of measurement point in an arbitrary direction. Next, a calculation power distribution (a design power distribution) is created. Further, a difference distribution between an actually measured power distribution, which indicates an actual power distribution, and a calculation power distribution is obtained. Further, the difference distribution is differentiated to obtain a difference index, and an evaluation is performed based on the difference index to evaluate whether there is a difference which greatly changes locally in a lens, and evaluate the degree of the difference.

Abstract: In a progressive-addition lens having a progressive surface on one side and an aspherical or atoroidal surface on the other side, the lens shape is designed so that a high degree of aberration correction can be carried out on the periphery of the lens and the distance power and addition power of the lens acting on the eye of a wearer substantially correspond to the distance power and addition power measured by a lens meter. A progressive-addition lens includes a progressive surface and an aspherically designed surface formed of an aspherical or atoroidal surface, and the reference point of the aspherically designed surface is located in the vertical direction of the lens below a prism reference point of the progressive surface and above a near design reference point.

Abstract: A spectacle lens capable of obtaining a good vision without feeling of discomfort, even being fitted into a frame having a large front angle, and a method of creating the shape data of the spectacle lens having dioptric power to be fitted into a frame having a lens front angle. The method corrects the shape data of a lens back surface so that the prismatic effect undergone via the lens of initial lens shape by a plurality of rays passing through a rotation center of the eye in a case where a lens front angle is provided is identical or close to the prismatic effect undergone via the lens of initial lens shape by the plurality of rays passing through the rotation center of the eye in a case where no lens front angle is provided.

Abstract: In a progressive-addition lens having a progressive surface on one side and an aspherical or atoroidal surface on the other side, the lens shape is designed so that a high degree of aberration correction can be carried out on the periphery of the lens and the distance power and addition power of the lens acting on the eye of a wearer substantially correspond to the distance power and addition power measured by a lens meter. A progressive-addition lens includes a progressive surface and an aspherically designed surface formed of an aspherical or atoroidal surface, and the reference point of the aspherically designed surface is located in the vertical direction of the lens below a prism reference point of the progressive surface and above a near design reference point.

Abstract: The present invention is to provide a lens evaluation method capable of easily evaluating whether there is a difference which greatly changes locally in a lens, and evaluating the degree of the difference. According to the lens evaluation method of the present invention, first, power a distribution of a plurality of measurement point in an arbitrary direction. Next, a calculation power distribution (a design power distribution) is created. Further, a difference distribution between an actually measured power distribution, which indicates an actual power distribution, and a calculation power distribution is obtained. Further, the difference distribution is differentiated to obtain a difference index, and an evaluation is performed based on the difference index to evaluate whether there is a difference which greatly changes locally in a lens, and evaluate the degree of the difference.

Abstract: The present invention is to provide a method for easily evaluating whether or not a relative positional shift generated between both surfaces of a bi-aspherical type lens is within an allowance during the manufacturing process of the bi-aspherical type lens. According to the evaluation method of the progressive-addition lens of the present invention, first, powers of the progressive-addition lens at a plurality of are measured to obtain an actually measured power distribution. Next, a comparison power distribution created based on the actually measured power distribution and a defective power distribution prepared in advance are compared with each other to perform similarity search between the both.

Abstract: In a progressive-addition lens having a progressive surface on one side and an aspherical or atoroidal surface on the other side, the lens shape is designed so that a high degree of aberration correction can be carried out on the periphery of the lens and the distance power and addition power of the lens acting on the eye of a wearer substantially correspond to the distance power and addition power measured by a lens meter. A progressive-addition lens includes a progressive surface and an aspherically designed surface formed of an aspherical or atoroidal surface, and the reference point of the aspherically designed surface is located in the vertical direction of the lens below a prism reference point of the progressive surface and above a near design reference point.