Abstract: A spectacle lens for at least one eye of a user, a method for producing a spectacle lens, and a computer program product having executable instructions for performing the method for producing the spectacle lens are disclosed. The spectacle lens has a permanent marking which is or contains a diffractive structure, wherein a diffractive pattern generated by illumination of the diffractive structure is configured to be invisible upon a first kind of illumination and configured to be visible only upon a second kind of illumination. The permanent markings on the spectacle lens are, on one hand, invisible to the user or to a spectator looking at the user wearing the spectacle lens without utilizing specially selected optical aids but, on the other hand, enables continued control of the spectacle lens in front of the eye of the user by an optician or a specifically designated optical sensor.

Abstract: A spectacle lens for at least one eye of a user, a method for producing a spectacle lens, and a computer program product having executable instructions for performing the method for producing the spectacle lens are disclosed. The spectacle lens has a permanent marking which is or contains a diffractive structure, wherein a diffractive pattern generated by illumination of the diffractive structure is configured to be invisible upon a first kind of illumination and configured to be visible only upon a second kind of illumination. The permanent markings on the spectacle lens are, on one hand, invisible to the user or to a spectator looking at the user wearing the spectacle lens without utilizing specially selected optical aids but, on the other hand, enables continued control of the spectacle lens in front of the eye of the user by an optician or a specifically designated optical sensor.

Abstract: Method implemented by computer for optimizing a set of optical lens blanks used to manufacture a set of optical lenses, each optical lens comprising first and second optical surfaces, the first and second optical surfaces being connected by a external periphery surface, the method comprising: a data providing step during which a set of data for every optical lens of the set of optical lenses is provided, the data comprising at least contour data representative of an external periphery surface of the optical lens, a first dataset representative of the first optical surface of the optical lens and a second dataset representative of the second optical surface of the optical lens; a supply cost function providing step during which a supply cost function is provided, the supply cost function being a function of the number of different optical lens blank comprised in the set of optical lens blanks.

Abstract: A computer-implemented method for calculating or assessing a spectacles lens for an eye of a spectacles wearer. The method includes (a) providing an association of at least one imaging property or aberration of a spectacle lens system with the vision of the spectacles wearer, or of an average spectacles wearer, when observing an object through the spectacles lens system; (b) determining or prescribing a target function for the spectacles lens to be calculated or assessed, in which the association from step (a) is to be evaluated; and (c) calculating or assessing the spectacles lens to be calculated or assessed by evaluating the target function, wherein the target function is evaluated at least once.

Abstract: A method for determining an ophthalmic lens adapted to a wearer, the method including: receiving wearer data including at least the ophthalmic prescription of the wearer; receiving a set of object points associated with target optical performances based on the wearer data; determining an ophthalmic lens adapted to the wearer, the ophthalmic lens providing optical performances, for light rays propagating from the set of object points to the center of rotation of the eye of the wearer passing through the ophthalmic lens, the closest to the target optical performances.

Abstract: The supply systems for providing spectacle ophthalmic lenses have improved efficacy, in particular with respect to lens blank picking performance and/or lens manufacturing performance.

Abstract: Method implemented by computer means for optimizing a measured contour of an opening of a spectacle frame, the method comprising: a contour data providing step, a working contour defining step, during which a working contour of the spectacle frame is defined, a first contour cost function providing step, during which a first contour cost function function of the mth derivative of the curve of the contour is provided, a set of contour cost functions providing step, during which a set of contour cost functions is provided, a global contour cost function evaluation step during which a global contour cost function is evaluated, a contour modifying step, during which the working contour is modified, wherein the global contour cost function evaluation and contour modifying steps are repeated so as to minimize the global contour cost function.

Abstract: Method for assessing an optical property of kth order of an optical element at an evaluation point. The optical element has a boundary surface formed of a refractive base surface and a phase-modifying optical element. The method includes determining the properties of a wavefront in the local surrounding of the evaluation point by means of a local wavefront tracing, and determining the optical property at the evaluation point based on the properties of the wavefront in the local surrounding of the evaluation point, wherein the local wavefront tracing has a local wavefront tracing upon passage through the boundary surface, and the local wavefront tracing upon passage through the boundary surface is performed according to the equation for the local wavefront tracing through the refractive base surface, the equation being supplemented by an additive additional term PK(k).

Abstract: A method for providing a personalized optical system for a wearer wherein the optical system characterizes a spectacle ophthalmic lens comprising the following steps: a) providing a visual performance level (VPL) value of at least one eye of the wearer; b) providing a set of rules linking at least the visual performance level of step a) with at least one optical criterion chosen among one or both of the two following optical criteria groups consisting of central vision optical criterion (CVOC) group and peripheral vision optical criterion (PVOC) group; c) calculating the physical and geometrical parameters of the personalized optical system or selecting the personalized optical system in an optical systems data base comprising a plurality of optical systems, so that to meet the set of rules of step b) according to the visual performance level data provided in step a).

Abstract: A method for producing a series of base lenses, which cover a predetermined power range, wherein each base lens of the series has a base power different from the base powers of the other base lenses of the series, and has at least one diffractive base grating, the method comprising: specifying the base powers of each base lens of the series and calculating the base grating of each base lens of the series so as to minimize the color fringe of the respective base lens with the specified base power in a predetermined region of the spectacle lens.

Abstract: A progressive-lens designing system includes a manufacturer-side terminal installed in a lens manufacturer connected to a shop-side terminal installed in a spectacle shop or any other location via a network. The manufacturer-side terminal includes an optimization coefficient setting section that uses a variety of data received from the shop-side terminal to set an optimization coefficient for each target object in specific work, a dioptric power computing section that computes target dioptric power for each target object, a lens designing section that performs lens design, and an order processing section that performs order processing when receiving an order placed from the shop-side terminal.

Abstract: Method for optimization of a progressive spectacle lens, which method comprises: defining a starting nominal astigmatism distribution for the spectacle lens; determining a transformed nominal astigmatism distribution and optimizing the spectacle lens on the basis of the transformed nominal astigmatism distribution, wherein the determination of a transformed nominal astigmatism distribution comprises multiplication of the maximum temporal nominal astigmatism of the starting nominal astigmatism distribution by a factor k as a result of which a modified maximum temporal astigmatism is obtained, wherein k is a function of a prescription value, and/or at least of one parameter of the spectacle lens or of the arrangement thereof in front of the eyes, and transformation of the starting nominal astigmatism distribution on the basis of the modified maximum temporal astigmatism.

Abstract: Optimization and production of a spectacle lens for a specific wearing situation for correcting at least one astigmatic refraction of an eye of a spectacles wearer, which in a reference viewing direction of the eye has a cylinder reference value and a cylinder reference axis, comprising: specifying an object distance for at least one evaluation point of the spectacle lens; determining a transformed astigmatic refraction for the at least one evaluation point of the spectacle lens from the cylinder reference value and the cylinder reference axis depending on the specified object distance; and optimizing the spectacle lens such that for the at least one evaluation point a correction of the transformed astigmatic refraction by the spectacle lens in the specific wearing situation is taken into consideration, wherein determining the transformed astigmatic refraction comprises determining a transformed cylinder value and/or a transformed cylinder axis depending on the specified object distance.

Abstract: An optical system is configured using a coordinate system such that an origin 1 is placed at a middle point of centers of rotations 1L and 1R of both eyeballs 10L and 10R, and an object is specified in a viewing direction from the origin 1. A reference value of an angle of convergence ?CH0 is calculated with lines of fixations 13L0 and 13R0, a viewing direction of the lines of fixation being an object 12 which is placed at an intersection point at which the lines of fixations 13L0 and 13R0 cross after passing through design reference points 11PL and 11PR of eyeglass lenses 11L, 11R. The angle of convergence is calculated with the lines of fixations which extend to an object evaluation point in an arbitrary viewing direction and pass the eyeglass lenses, and a convergence aberration is calculated from a difference between the angle of convergence and the reference value of the angle of convergence ?CHO.

Abstract: A method and apparatus for producing a first spectacle lens of a pair of spectacle lenses to be used with a second spectacle lens for a specific situation of wear, in which optical parameters for the spectacle lens are calculated to minimize the value of a target function that corresponds to the pair of spectacle lenses. The target function is the sum of a first monocular function, with a weighting factor, that depends on the values of a first monocular optical property at a plurality of monocular evaluation points, a the binocular function, with a weighting factor, that depends on the values of a second monocular optical property at the plurality of pairs of binocular evaluation points, and a remainder term.

Abstract: A computer-implemented method for calculating or optimizing a spectacle lens for at least one eye of a spectacle wearer. Refraction data of the at least one eye of the spectacle wearer is collected. An individual eye model is defined, wherein the eye model defines at least the topography of a corneal front surface of the at least one eye, position and power of a lens of the eye, and a retina position of the eye such that the eye exhibits the collected refraction data. A first surface and a second surface for the spectacle lens to be calculated or optimized is specified. The path of a main ray through at least one visual point of at least one spectacle lens surface to be calculated or optimized is determined. A spherical wavefront incident on the first surface of the spectacle lens along the main ray is specified.

Abstract: Adjustment of an eyeglass lens or a pair of eyeglasses by means of an individual brightness-dependent centering of an eyeglass lens. In particular, a method for adjusting an individual eyeglass lens for at least one eye of an eyeglass wearer. The method includes defining an individual usage situation which includes at least one target brightness value for the light to be captured by the at least one eye; determining a position of the pupil in at least one direction of view of the at least one eye which occurs or is expected at the at least one target brightness value; determining a reference point of the eyeglass lens, in which the eyeglass lens effects a required correction of individual refraction data for the at least one direction of view; on the basis of the determined individual value of the pupil position, providing and arranging the eyeglass lens in such a manner that the at least one reference point of the eyeglass lens is arranged in front of the at least one eye of the eyeglass wearer.

Abstract: A method, a system and a computer program product are provide for optimizing a spectacle lens for a wearer with a selectable quality grade. In particular, a set of individual parameters is determined for the wearer and a desired quality grade is identified. Depending the identified quality grade, the set of individual parameters is adapted and a surface of the spectacle lens is calculated based on the adapted set of individual parameters.

Abstract: The invention relates to a finished or semi-finished lens which comprises: a disc containing all the points of the lens that have the same abscissa and the same ordinate as points located within a circle in the reference plane having a diameter of 30 millimeters and centered on the prism reference point; a progression length of less than 14.5 millimeters; a first specific point having a cylinder value equal to the maximum cylinder value of all the points of the lens located in the nasal area and in the disc; and a second specific point having a cylinder value equal to the maximum cylinder value of all the points of the lens located in the temporal area and in the disc; a first ratio between: the maximum gradient of the cylinder for the points of the lens that have the same abscissa and the same ordinate as the points located on segments connecting the mounting cross to the first and second specific points, and surface addition of less than 0.

Abstract: A method for calculating or optimizing an ophthalmic lens design comprising the steps of providing a given ophthalmic lens design and assessing the given design by a computer comprising a media suitable for storing electronic instructions.

Abstract: Method for determining the edge contour of an uncut spectacle lens comprises: a spectacle frame data providing step, a minimum edge thickness providing step, an initial contour providing step, a thickness determining step, an optimized point selecting step, a repeating step, and a edge contour determining step.

Abstract: An individual spectacle lens design for a progressive spectacle lens exhibiting an individual vertical position of the distance and/or the near reference points, which can be variably adjusted, is calculated. A starting design exhibiting a predefined vertical position of the distance and/or the near reference points is determined; the individual spectacle lens design is calculated having the desired, individual vertical position of the distance and/or near reference points. The calculation of the individual spectacle lens design includes calculating the target value for the spatial distribution of at least one optical property of the individual spectacle lens by a mapping and a transform, where the starting design has a corresponding target value.

Abstract: Eyewear can include lenses having perimeters that are customized for an intended wearer. The perimeter of the lenses can be determined based on anatomical features of the wearer's face, the wearer's field of vision, or other parameters specific to that individual. Determination of the lens perimeters can involve developing a three-dimensional model of a wearer's face and/or head, demarcating a lens perimeter over an obtained image of a user's face, or delineating the boundary of a wearer's peripheral vision. A provisional lens perimeter obtained by any of these methods may be modified in curvature and/or size to arrive at a desired final lens perimeter. Customized lenses can be fabricated based on the determined lens perimeters. The customized lenses can be assembled into completed eyewear that is customized for a wearer, for example having shapes, sizes, and designs not otherwise possible.

Abstract: A process for designing an ophthalmic progressive eyeglass comprises providing an initial front surface and an initial back surface. Respective addition values of front and back surfaces of the eyeglass are varied based on said initial front and back surfaces using a surface derivation tool. These surface addition values are selected so that the eyeglass exhibits an eyeglass addition value which matches a wearer's prescription and a value for a design feature which matches a target value. Said target value may be used for customizing the ophthalmic progressive eyeglass. The process does not require point-to-point surface optimization.

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: The invention relates to a method for calculation of the local magnification and/or the local distortion of a spectacle lens in at least one predetermined or predeterminable viewing direction, with the spectacle lens being designed to correct a refraction deficit of an eye, and having at least one object-side surface and one second eye-side surface, comprising the following steps: Calculation for the predetermined or predeterminable viewing direction of the profile of a main beam which originates from a predetermined or predeterminable infinitesimally small object and, after refraction by the spectacle lens, passes through the rotation point of the eye, through the entrance pupil of the eye or through the principal plane of the eye; determination of the main curvatures and directions of a local wavefront associated with the main beam on refraction by the spectacle lens; calculation of the local magnification and/or the local distortion of the spectacle lens from the determined main curvatures and directions o

Abstract: The invention relates to a method, a computer program product and a system for designing or producing a spectacle lens for a spectacle wearer. Said method consists of the following steps: individual user data or application data of the spectacle wearer is obtained; the design concept for the spectacle lens having a plurality of evaluation points is determined; a main beam path through the plurality of evaluation points is determined; a local wavefront is specified for each of the main beams in the surroundings of the respective main beam; optical properties of the spectacle lens are determined on the evaluation points by determining an influence of the spectacle lens on the local wavefronts in the surroundings of the respective evaluation point; and the design concept is evaluated in accordance with the determined optical properties and the individual user data.

Abstract: A method for determining by optimization a set of progressive ophthalmic lenses for a given user for whom a near vision power addition (Addn) has been prescribed includes the following steps: measuring the user's near vision individual physiological parameters; determining an ergorama associating, on each lens, a target point in each look direction in worn conditions; determining a target power defect and a resulting target astigmatism for each direction of look under worn conditions, the target power defect and the resulting target astigmatism being determined from the user's measured physiological parameters; computing the power required for each lens for said ergorama by successive iterations to reach the target power defect and the target astigmatism for each look direction.

Abstract: A process for controlling a lens manufacturing process comprising the steps of: a) manufacturing a master lens according to a manufacturing process using a manufacturing device, b) measuring by using at least a measuring device at least one parameter of the master lens of step a), c) recording the value of the parameter, d) repeating regularly step a) to c) and checking the evolution of the parameter over time, wherein the evolution of at least one parameter of the manufacturing device used during the lens manufacturing process is checked over time and the evolution over time of at least one parameter of the master lens is related with the evolution over time of the at least one parameter of the manufacturing device.

Abstract: The invention relates in particular to a computer-implemented method for calculating or optimizing a spectacle lens, comprising the steps of: specifying at least one surface for the spectacle lens to be calculated or optimized; determining the course of a main ray (10) through at least one visual point (i) of the at least one surface; determining a first primary set (sio) and a second primary set (eiok) of coefficients of the local aberration of a local wavefront (18) going out from the at least one visual point (i) in a surrounding of the main ray (10), wherein the first primary set of coefficients (sio) defines the spherical and astigmatic aberration of the outgoing local wavefront and the second primary set of coefficients (eiok) defines at least one further higher-order aberration (k>2) of the outgoing local wavefront; specifying at least one function epk=ƒ(eok) which assigns a second secondary set of coefficients (epk) to a second primary set of coefficients (eok), said second secondary set of coef

Abstract: Method for optimization of a progressive spectacle lens, which method comprises: defining a starting nominal astigmatism distribution for the spectacle lens; determining a transformed nominal astigmatism distribution and optimizing the spectacle lens on the basis of the transformed nominal astigmatism distribution, wherein the determination of a transformed nominal astigmatism distribution comprises multiplication of the maximum temporal nominal astigmatism of the starting nominal astigmatism distribution by a factor k as a result of which a modified maximum temporal astigmatism is obtained, wherein k is a function of a prescription value, and/or at least of one parameter of the spectacle lens or of the arrangement thereof in front of the eyes, and transformation of the starting nominal astigmatism distribution on the basis of the modified maximum temporal astigmatism.

Abstract: A method of customizing vision correction including measuring optical aberration data of a patient's eye and calculating a lens definition based on the optical aberration data, wherein calculating the lens definition comprises calculating a correction of at least one low order aberration and at least one high order aberration and is based at least partly on the patient's pupil size.

Abstract: A method of making a spectacle lens providing at least an astigmatic correction includes measuring a direction of an axis of an astigmatism of an eye for each of three different directions of gaze of the eye. Thereafter, a position of the spectacle lens is determined relative to the eye. A shape of a surface of the spectacle lens is computed based on the determined position of the spectacle lens relative to the eye and the at least three measured directions of the axis of the astigmatism. A primary orientation of the eye is determined based on the three measured directions of the axis of the astigmatism. The shape of the surface of the spectacle lens is calculated based on the determined position of the spectacle lens relative to the eye and by applying Listing's Law based on the determined primary orientation of the eye.

Abstract: A method of designing and evaluating a progressive power lens where the intersection of the wearer's line of sight, and the refractive surface of the lens is the primary line of fixation (L), the positions upon the primary line of fixation corresponding to far-field vision and near-field vision are the points (F) and (ON), respectively, and the distance of the displacement of (ON) toward the nose in the horizontal direction relative to (F) is the inward shift (OI). Upon the principal meridian curve (M) passing through (F), the point at which the profile curve (H) passing through (ON) in the horizontal direction and (M) is (DN), the displacement of (DN) towards the nose in the horizontal direction relative to (F) is the inward shift (DH), and OI<DH.

Abstract: A method for producing a series of base lenses, which cover a predetermined power range, wherein each base lens of the series has a base power different from the base powers of the other base lenses of the series, and has at least one diffractive base grating, the method comprising: specifying the base powers of each base lens of the series; and calculating the base grating of each base lens of the series so as to minimize the color fringe of the respective base lens with the specified base power in a predetermined region of the spectacle lens.

Abstract: For evaluating custom made eyeglass lenses using a visual fatigue function, the visual fatigue function includes at least one of or both of a positive relative convergence and a negative relative convergence of the positive relative convergence, the negative relative convergence, a positive relative accommodation, a negative relative accommodation and a vertical fusional vergence.

Abstract: More appropriate evaluation, design, and manufacture are made feasible by taking visual functions into consideration more appropriately. In order to achieve this object, in the present invention, provided is a spectacle lens evaluation method for evaluating spectacle lenses using a visual acuity function, characterized in that the visual acuity function includes relative accommodation power as a factor, the relative accommodation power referring to the range expressed in terms of diopter in which distinct vision is achieved while maintaining convergence of a gaze point.

Abstract: A method of calculating an optical system (OS) of an ophthalmic lens according to a given spectacle frame comprising the steps of: providing geometrical data of the spectacle frame, providing wearer data, and optimization of the optical system (OS) according to at least the criteria consisting of the geometrical data of the spectacle frame, the wearer data and at least one positioning data, so as to generate at least two optical surfaces (S1, S2).

Abstract: In one aspect of the present invention, a method for manufacturing a prescription lens includes obtaining information of a prescription lens and a frame to accommodate the prescription lens, the information of the prescription lens comprising a lens power, an optical zone and a spherical front base curve, and the information of the frame comprises a frame curve; calculating the maximum lens thickness of the prescription lens at the optical zone according to the information of the prescription lens; selecting a lens according to the calculated maximum lens thickness at the optical zone, the information of the prescription lens and the frame; and processing the selected lens so as to obtain the prescription lens having an intermediate zone surrounding the optical zone and an edge zone surrounding the intermediate zone such that the thickness of the edge zone is substantially thinner than the maximum lens thickness of the optical zone.

Abstract: Method for determining the edge contour of an uncut spectacle lens comprises: a spectacle frame data providing step, a minimum edge thickness providing step, an initial contour providing step, a thickness determining step, an optimized point selecting step, a repeating step, and a edge contour determining step.

Abstract: A method of making a pair of spectacle lenses which may reduce induced binocular vision distortions where wearer and frame metrics and a lens class are inputted into a computer program, and the computer program determines the left and right lens front curve radius in which there is a substantially linear relationship between the rate of change of lateral vergence and degree of ocular rotation and then adjusts the left and right lens front curve radius and the left and right lens centre thickness such that the lateral inter-ocular static magnification target value is between about ?3% and about +3% in the lateral plane and the stimulus to near vergence is within the wearer's vergence limits. The computer program then determines a left and right lens index of refraction and a left and right lens material and the generated lens parameters are then used to machine the spectacle lenses.

Abstract: A process for designing an ophthalmic progressive eyeglass comprises providing an initial front surface and an initial back surface. Respective addition values of front and back surfaces of the eyeglass are varied based on said initial front and back surfaces using a surface derivation tool. These surface addition values are selected so that the eyeglass exhibits an eyeglass addition value which matches a wearer's prescription and a value for a design feature which matches a target value. Said target value may be used for customizing the ophthalmic progressive eyeglass. The process does not require point-to-point surface optimization.

Abstract: A method of determining binocular performance of a pair of spectacle lenses comprises: a eyes characteristics providing step, a pair of spectacle lenses providing step, a environment providing step, a binocular performance criteria selecting step, and a binocular performance criteria determining step, wherein the at least one binocular performance criterion is selected among one or a combination of the following criteria groups consisting of central vision criteria group and/or peripheral vision criteria group.

Abstract: A method of calculating an optical system (OS) of an ophthalmic lens according to a given spectacle frame comprising the steps of: providing geometrical data of the spectacle frame, providing deformability data of the spectacle frame, providing wearer data, providing a surface curvature of a front face of the ophthalmic lens, and optimization of both the optical system (OS) and the edging parameter according to the list of the optimization criteria consisting of the geometrical and deformability data of the spectacle frame and the wearer data, so as to generate at least one optical surface different from the front surface of the lens.

Abstract: Methods of eye gaze tracking are provided using magnetized contact lenses tracked by magnetic sensors and/or reflecting contact lenses tracked by video-based sensors. Tracking information of contact lenses from magnetic sensors and video-based sensors may be used to improve eye tracking and/or combined with other sensor data to improve accuracy. Furthermore, reflective contact lenses improve blink detection while eye gaze tracking is otherwise unimpeded by magnetized contact lenses. Additionally, contact lenses may be adapted for viewing 3D information.

Abstract: The invention relates to a method for producing a progressive spectacle lens and to a corresponding apparatus, a computer program product, a storage medium and to the use of a progressive spectacle lens. The invention also relates to a method for producing a progressive spectacle lens for correcting defective vision of a spectacle wearer, comprising the following steps: the vertical and/or the horizontal spatial position of a distance reference point and/or a near reference point is specified or determined in accordance with individual data of the spectacle wearer; the spectacle lens is optimized or calculated such that the required dioptric effect of the spectacle lens is obtained in the individually determined distance reference point and/or the near reference point.

Abstract: More appropriate evaluation, design, and manufacture are made feasible by taking visual functions into consideration more appropriately. In order to achieve this object, in the present invention, provided is a spectacle lens evaluation method for evaluating spectacle lenses using a visual acuity function, characterized in that the visual acuity function includes relative accommodation power as a factor, the relative accommodation power referring to the range expressed in terms of diopter in which distinct vision is achieved while maintaining convergence of a gaze point.

Abstract: A method, a system and a computer program product are provide for optimizing a spectacle lens for a wearer with a selectable quality grade. In particular, a set of individual parameters is determined for the wearer and a desired quality grade is identified. Depending the identified quality grade, the set of individual parameters is adapted and a surface of the spectacle lens is calculated based on the adapted set of individual parameters.

Abstract: More appropriate evaluation, design, and manufacture are made feasible by taking visual functions into consideration more appropriately. In order to achieve this object, in the present invention, provided is a spectacle lens evaluation method for evaluating spectacle lenses using a visual acuity function, characterized in that the visual acuity function includes relative accommodation power as a factor, the relative accommodation power referring to the range expressed in terms of diopter in which distinct vision is achieved while maintaining convergence of a gaze point.

Abstract: A design method of a spectacle lens, includes: measuring an angle formed by a direction of a head of a person seeing the front without lens and a direction of the head of the person seeing an object located in a direction angled to the front direction of the person without lens to calculate a visual action index Mn according to the following equation (1) as an initial value; temporarily designing a spectacle lens based on the visual action index; and simulating visual action of the person wearing the temporarily designed spectacle lens and correcting the visual action index based on the simulation result M n = ? n ? n ( 1 ) wherein ?n is an angle formed by the front direction of the person and a direction in which the object actually exists, ?n is a rotation angle of the head of the person seeing the object without lens, and n represents the object.