Abstract: With respect to the evaluation of custom-made eyeglass lenses using a binocular visual acuity function, a measurement value including essentially at least one of or both of a positive relative convergence or 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 is provided as a factor.

Abstract: The present invention relates to a method of manufacturing a formed article comprising forming an upper surface of a glass material that has been positioned on a forming surface of a mold to obtain the formed article by heating the glass material to a temperature permitting deformation to bring a lower surface of the glass material into tight contact with the forming surface. Glass having upper and lower surfaces being spherical in shape is employed as the glass material, a mold having a forming surface being a free-form surface other than a spherical surface is employed as the mold, the upper surface of the glass material is formed into a roughly offset surface relative to the forming surface of the mold. The present invention permits the manufacturing of formed articles of desired shape with high precision by hot sag molding method. The present invention also permits the easy and simple determination of the surface shapes of molds and glass materials employed in hot sag molding method.

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: 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: More appropriate evaluation, design, and manufacture are made feasible by taking visual performances into consideration more appropriately. In order to achieve this object, in the present invention, spectacle lenses are evaluated using a visual acuity function including a factor representing physiological astigma. The physiological astigma herein means astigma in the phenomenon that an improved visual acuity is yielded when slight astigma is present in the region where the accommodation power is lower than the region indicating the range of positive relative accommodation power in which the accommodation power increases among the relative accommodation power as adaptable accommodation power in a state that convergence does not change.

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: 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: 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 11 PR 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: With respect to the evaluation of custom-made eyeglass lenses using a binocular visual acuity function, a measumrnet value including essentially at least one of or both of a positive relative convergence or 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 is provided as a factor.

Abstract: More appropriate evaluation, design, and manufacture are made feasible by taking visual performances into consideration more appropriately. In order to achieve this object, in the present invention, spectacle lenses are evaluated using a visual acuity function including a factor representing physiological astigma. The physiological astigma herein means astigma in the phenomenon that an improved visual acuity is yielded when slight astigma is present in the region where the accommodation power is lower than the region indicating the range of positive relative accommodation power in which the accommodation power increases among the relative accommodation power as adaptable accommodation power in a state that convergence does not change.

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 performance of the optical system is evaluated based on a correlation between a visual acuity when looking through the optical system and the chromatic aberration of magnification of the optical system, the correlation being a proportional relation such that, when the visual acuity is expressed by a logarithmic visual acuity, the logarithmic visual acuity deteriorates substantially in proportion to the chromatic aberration of magnification, or on a correlation between the visual acuity and an optical value regarding the chromatic aberration of magnification which is substantially equivalent to the correlation.

Abstract: The present invention relates to a method of manufacturing a formed article comprising forming an upper surface of a glass material that has been positioned on a forming surface of a mold to obtain the formed article by heating the glass material to a temperature permitting deformation to bring a lower surface of the glass material into tight contact with the forming surface. Glass having upper and lower surfaces being spherical in shape is employed as the glass material, a mold having a forming surface being a free-form surface other than a spherical surface is employed as the mold, the upper surface of the glass material is formed into a roughly offset surface relative to the forming surface of the mold. The present invention permits the manufacturing of formed articles of desired shape with high precision by hot sag molding method. The present invention also permits the easy and simple determination of the surface shapes of molds and glass materials employed in hot sag molding method.

Abstract: An evaluation of an optical system with respect to visual acuity is appropriately performed, with a chromatic aberration of magnification of the optical system being taken into consideration. A performance of the optical system is evaluated based on a correlation between a visual acuity when looking through the optical system and the chromatic aberration of magnification of the optical system, the correlation being a proportional relation such that, when the visual acuity is expressed by a logarithmic visual acuity, the logarithmic visual acuity deteriorates substantially in proportion to the chromatic aberration of magnification, or on a correlation between the visual acuity and an optical value regarding the chromatic aberration of magnification which is substantially equivalent to the correlation.

Abstract: A performance of the optical system is evaluated based on a correlation between a visual acuity when looking through the optical system and the chromatic aberration of magnification of the optical system, the correlation being a proportional relation such that, when the visual acuity is expressed by a logarithmic visual acuity, the logarithmic visual acuity deteriorates substantially in proportion to the chromatic aberration of magnification, or on a correlation between the visual acuity and an optical value regarding the chromatic aberration of magnification which is substantially equivalent to the correlation.

Abstract: A method for displaying an optical performance preferably applicable to also an axially asymmetric spectacle lens is provided. First, a clear visual region of the spectacle lens is determined using an evaluation function which evaluates the optical performance of the spectacle lens. Next, a clear visual angle which depends on a size of the clear visual region corresponding to a vertex angle of a spherical cone is calculated when the spherical cone which has an equal solid angle with a solid angle including the determined clear visual region from a center of rotation of an eye and which is symmetrical to an optical axis of the spectacle lens is assumed. Next, the calculated clear visual angle is expressed by a unit of degree.

Abstract: It is made possible to easily obtain a spectacle lens with higher performance in a spectacle lens designing method in which an eyeball motion (Listing's Law) is taken into consideration. A spectacle lens designing method in which an eye motion (Listing's Law) is taken into consideration, and which uses, as an evaluation function regarding visual acuity constituting a merit function which is used in optimization calculation, a visual acuity evaluation function (logMAR) derived in an ordinary manner from a visual acuity measured value V which is actually measured. Note that the visual acuity evaluation function (logMAR) is represented by the following equation (1), letting a curvature of field be an ordinary aberration of a spectacle lens, and a residual astigmatism be an astigmatism extendedly defined from the spectacle lens designing in which the Listing's Law is taken into consideration the visual acuity evaluation function (logMAR)=log10(1/V(curvature of field, residual astigmatism)).

Abstract: A spectacle lens is designed by using a value determined by either measuring or specifying for an individual spectacles wearer the value of the distance VR from a reference point on the back surface of a spectacle lens to the center of rotation of the eye, which adds together the value of the distance VC from a reference point of the back surface of a spectacle lens to the vertex of the cornea of the eye of the spectacles wearer at spectacle lenses wearing time, which is one of the required data in spectacle lens design, and the distance CR from the above-mentioned vertex of the cornea to the center of rotation of the eye, and manufacturing a spectacle lens based on this design specification.

Abstract: It is made possible to easily obtain a spectacle lens with higher performance in a spectacle lens designing method in which an eyeball motion (Listing's Law) is taken into consideration. A spectacle lens designing method in which an eye motion (Listing's Law) is taken into consideration, and which uses, as an evaluation function regarding visual acuity constituting a merit function which is used in optimization calculation, a visual acuity evaluation function (logMAR) derived in an ordinary manner from a visual acuity measured value V which is actually measured. Note that the visual acuity evaluation function (logMAR) is represented by the following equation (1), letting a curvature of field be an ordinary aberration of a spectacle lens, and a residual astigmatism be an astigmatism extendedly defined from the spectacle lens designing in which the Listing's Law is taken into consideration the visual acuity evaluation function (logMAR)=log10(1/V(curvature of field, residual astigmatism))??(1).

Abstract: A method for displaying an optical performance preferably applicable to also an axially asymmetric spectacle lens is provided. First, a clear visual region of the spectacle lens is determined using an evaluation function which evaluates the optical performance of the spectacle lens. Next, a clear visual angle which depends on a size of the clear visual region corresponding to a vertex angle of a spherical cone is calculated when the spherical cone which has an equal solid angle with a solid angle including the determined clear visual region from a center of rotation of an eye and which is symmetrical to an optical axis of the spectacle lens is assumed. Next, the calculated clear visual angle is expressed by a unit of degree.