Abstract: A progressive power lens that prevents degradation in optical characteristics invited by deviation of a pantoscopic angle from the standard value. The lens includes an outer refractive surface and an inner refractive surface, at least one of which is a progressive surface. Because the amount and direction of aberrations generated in distance and near portions are different, correction is given to either or both of the surface powers of the outer and inner surfaces of the lens such that the distance and near portions are differently corrected.

Abstract: A progressive power lens that prevents degradation in optical characteristics invited by deviation of a pantoscopic angle from the standard value. The lens includes an outer refractive surface and an inner refractive surface, at least one of which is a progressive surface. Because the amount and direction of aberrations generated in distance and near portions are different, correction is given to either or both of the surface powers of the outer and inner surfaces of the lens such that the distance and near portions are differently corrected.

Abstract: A spectacle lens having an aspherical surface on its one of front and back surfaces is provided. An outward normal line normal to the front surface at a centration point inclines with respect to an axis passing through the centration point and a center of rotation of an eye. A cross section of the aspherical surface defined by a plane including the outward normal line and the axis is asymmetrical.

Abstract: A progressive power lens having a positive vertex power in a distance portion is provided. At least a back surface of the progressive power lens is configured as a progressive surface. The progressive power lens satisfies a condition: Pf + ADD 3 < D ? ? 1 < Pf + ADD ( 1 ) where Pf represents a vertex power in the distance portion along a vertical cross-section, ADD represents an addition power, and D1 represents a surface power of a front surface.

Abstract: A spectacle lens having an asphecrical surface on its one of front and back surfaces is provided. An outward normal line normal to the front surface at a centration point inclines with respect to an axis passing through the centration point and a center of rotation of an eye. A cross section of the aspherical surface defined by a plane including the outward normal line and the axis is asymmetrical.

Abstract: A method of designing a spectacle lens having a front surface and a back surface is provided. At least one of the front and back surfaces is formed as a rotationally asymmetrical aspherical surface.

Abstract: There is provided a multifocal spectacle lens having a front surface and a back surface each of the front surface and the back surface is formed as a multifocal surface or a progressive-power surface, distributions of surface power of the front surface and the back surface being different from each other.

Abstract: There is provided a spectacle lens having an outer surface and an inner surface, one of the outer and inner surfaces being configured to be a rotationally-asymmetrical aspherical surface. When a curvature at a coordinate (h,?) of the outer surface is represented by C1(h,?), a curvature at a coordinate (h,?) of the inner surface is represented by C2(h,?), and a difference between curvatures of the outer surface and the inner surface at the coordinate (h,?) is represented by C2-1(h,?)=C2(h,?)?C1(h,?), if C2-1(0,?)>0, within the ranges of 10 mm?h[mm]?20 mm and 30°??[°]?150° the spectacle lens satisfying a condition (1): C2-1(h,?+180)?C2-1(h,?)>0,??(1) and if C2-1(0,?)<0, the spectacle lens satisfying a condition (2): C2-1(h,?+180)?C2-1(h,?)<0.

Abstract: A method of designing a spectacle lens having a front surface and a back surface is provided. At least one of the front and back surfaces is formed as a rotationally asymmetrical aspherical surface.

Abstract: A progressive power lens having a positive vertex power in a distance portion is provided. At least a back surface of the progressive power lens is configured as a progressive surface. The progressive power lens satisfies a condition: Pf + ADD 3 < D ? ? ? 1 < Pf + ADD ( 1 ) where Pf represents a vertex power in the distance portion along a vertical cross-section, ADD represents an addition power, and D1 represents a surface power of a front surface.

Abstract: A progressive power lens belonging to a series of lenses according to the present invention is provided. If a first lens and a second lens randomly chosen from the series of progressive power lenses have a common spherical refractive power Sph [diopter] in the distance portions thereof, the Sph is greater than or equal to +1, and a base curve BC1 of the first lens is smaller than a base curve BC2 of the second lens, the first and second lenses satisfy a condition: Wds ? ( BC 1 , Sph ) Wns ? ( BC 1 , Sph ) Wdt ? ( BC 1 , Sph ) Wnt ? ( BC 1 , Sph ) < Wds ? ( BC 2 , Sph ) Wns ? ( BC 2 , Sph ) Wdt ? ( BC 2 , Sph ) Wnt ? ( BC 2 , Sph ) .

Abstract: According to a method of manufacturing a progressive power spectacle lens, available vertex powers are divided into a plurality of vertex power groups, one surface of a spectacle lens has been formed as a common surface for the vertex powers within each of the plurality of vertex power groups, and an opposite surface of the spectacle lens is formed as a progressive power surface in accordance with a desired vertex power.

Abstract: Disclosed is a manufacturing method of a spectacle lens. The entire range of available vertex power of a spectacle lens is divided into a plurality of sections, and a plurality of types of semifinished lens blanks that are different in base curve are prepared for each of the sections. On the basis of required vertex power, choices of lens blanks are narrowed down. The plurality of types of the semifinished lens blanks can be selected for a specific vertex power. A customer selects one type of the semifinished lens blank based on weightings of optical performance and outward appearance. Further, a back surface of the selected semifinished lens blank is processed to form a finished lens according to a required specification for the spectacle lens.

Abstract: Disclosed are a single-vision aspherical spectacle lens to correct eyesight and a processing method thereof. The spectacle lens has front and back surfaces, one of which is an aspherical surface. A framing reference point that is coincident with a pupil position of a user when the lens is installed on a frame is decentered from a geometrical center of an uncut circular lens (a semifinished lens blank or an uncut finished lens). Further, the symmetric axis of the aspherical surface passes the framing reference point. With this construction, a lens blank of small-size can be employed for manufacturing a spectacle lens for a large-size frame, and the optical performance can be kept high.

Abstract: Disclosed is an aspherical spectacle lens having a prismatic power to correct hereophoria of an eye. The spectacle lens has front and back surfaces, one of which is a rotationally-asymmetrical aspherical surface. When the back surface is rotationally-asymmetrical, curvature of an intersection line of a plane containing the normal to the rotationally-asymmetrical surface at a framing reference point and the rotationally-asymmetrical surface at the prism base side is larger than that at the apex side. The framing reference point is coincident with a pupil position of a user when the spectacle lens is installed on a frame. On the other hand, when the front surface is rotationally-asymmetrical, the curvature of the intersection line at the prism base side is smaller than that at the apex side.

Abstract: There is provided a spectacle lens having an outer surface and an inner surface, one of the outer and inner surfaces being configured to be a rotationally-asymmetrical aspherical surface.

Abstract: A progressive power lens belonging to a series of lenses according to the present invention is provided. If a first lens and a second lens randomly chosen from the series of progressive power lenses have a common spherical refractive power Sph [diopter] in the distance portions thereof, the Sph is greater than or equal to +1, and a base curve BC1 of the first lens is smaller than a base curve BC2 of the second lens, the first and second lenses satisfy a condition: 1 Wds ⁡ ( BC 1 , Sph ) Wns ⁡ ( BC 1 , Sph ) Wdt ⁡ ( BC 1 , Sph ) Wnt ⁡ ( BC 1 , Sph ) < Wds ⁡ ( BC 2 , Sph ) Wns ⁡ ( BC 2 , Sph ) Wdt ⁡ ( BC 2 , Sph ) Wnt ⁡ ( BC 2 , Sph ) .

Abstract: There is provided a multifocal spectacle lens having a front surface and a back surface each of the front surface and the back surface is formed as a multifocal surface or a progressive-power surface, distributions of surface power of the front surface and the back surface being different from each other.

Abstract: A progressive-power spectacle lens includes a distance portion having a dioptric power for distance vision, a near portion having a dioptric power for near vision, and an intermediate portion having a progressive dioptric power between the distance portion and the near portion. At least one of front and back surfaces is formed as a progressive-power surface whose dioptric power varies depending upon a position thereon. The spectacle lens has a prismatic effect including a prescribed prismatic effect and unprescribed prismatic effect. A shape of the progressive-power surface of the spectacle lens is different from a shape of a progressive-power surface of a reference lens that is defined as a lens identical to the spectacle lens except that the prescribed prismatic effect is eliminated. The progressive surface of the spectacle lens is configured to compensate for aberration that is caused if the prescribed prismatic effect is added in the reference lens.

Abstract: Disclosed is a manufacturing method of a spectacle lens. The entire range of available vertex power of a spectacle lens is divided into a plurality of sections, and at least one type of semifinished lens blank whose front surface is finished is prepared for each of the sections. On the basis of required specification, one type of the semifinished lens blank is selected. Further, an aspherical shape design for processing the back surface of the selected semifinished lens blank is determined according to the required specification. The aspherical shape of the back surface is optimized such that average power errors or astigmatisms of the finished lenses having different vertex powers within the same section are approximately balanced. Finally the back surface is processed based on the determined aspherical shape.