Progressive spectacle lens having a variable refractive index and method for the design and production thereof

A product comprising:

• (i) a progressive power spectacle lens or (ii) a representation of the progressive power spectacle lens having instructions for the production thereof using an additive method, the representation being stored on a non-transitory data medium as computer-readable data, or (iii) a non-transitory data medium with a virtual representation of the progressive power spectacle lens as computer-readable data having instructions for the production thereof using an additive method, wherein the progressive power spectacle lens includes:
• a uniform substrate having a spatially varying refractive index, a front surface, and a back surface,
• wherein, during use as intended, the front surface and the back surface either jointly form outer surfaces of the progressive power spectacle lens or at least one of the front surface or the back surface is exclusively provided with one or more functional coatings which do not contribute or at each point contribute less than 0.004 dpt to a spherical equivalent of a dioptric power of the progressive power spectacle lens,
• wherein at least one of the front surface or the back surface is configured as a freeform surface, wherein
• (c) the refractive index varies in a first spatial dimension and in a second spatial dimension and in a third spatial dimension, wherein a distribution of the refractive index has no point symmetry and no axial symmetry at all.

A product comprising:

• (i) a progressive power spectacle lens or (ii) a representation of the progressive power spectacle lens having instructions for the production thereof using an additive method, the representation being stored on a non-transitory data medium as computer-readable data, or (iii) the non-transitory data medium having a virtual representation of the progressive power spectacle lens as computer-readable data and having instructions for the production thereof using an additive method, wherein the progressive power spectacle lens has:
• a front surface;
• a back surface;
• and
• a spatially varying refractive index,
• wherein at least one of the front surface or the back surface is configured as a freeform surface, the freeform surface being configured as a progressive surface,
• wherein the progressive power spectacle lens is made of a substrate having no individual layers and having the front surface, the back surface, and the spatially varying refractive index,
• wherein the substrate has at least one of a front surface coating including one or more individual layers or a back surface coating including one or more individual layers,
• wherein a difference between the spherical equivalent measured at each point on the front surface of the progressive power spectacle lens with the at least one of the front surface coating or the back surface coating and the spherical equivalent measured at each corresponding point on the front surface of a comparison progressive power spectacle lens without the front surface coating and without the back surface coating but with an identical substrate is less than a value from the group specified below:
• (a) the difference value is less than 0.001 dpt
• (b) the difference value is less than 0.002 dpt
• (c) the difference value is less than 0.003 dpt
• (d) the difference value is less than 0.004 dpt
• and wherein
• (b) the refractive index varies in a first spatial dimension and in a second spatial dimension and in a third spatial dimension, wherein the distribution of the refractive index in the first spatial dimension and the second spatial dimension in all planes perpendicular to the third spatial dimension has neither point symmetry nor axial symmetry.

A product comprising:

• (i) a progressive power spectacle lens or (ii) a representation of the progressive power spectacle lens having instructions for the production thereof using an additive method, the representation being stored on a data medium as computer-readable data, or (iii) the non-transitory data medium having a virtual representation of the progressive power spectacle lens as the computer-readable data and having instructions for the production thereof using an additive method, wherein the progressive power spectacle lens has:
• a front surface;
• a back surface;
• and
• a spatially varying refractive index,
• wherein at least one of the front surface or the back surface is configured as a freeform surface, wherein the freeform surface is configured as a progressive surface,
• wherein the progressive power spectacle lens is made of a substrate having no individual layers and having the front surface, the back surface, and the spatially varying refractive index,
• wherein the substrate has at least one of a front surface coating including one or more individual layers or a back surface coating including one or more individual layers,
• wherein a difference between a spherical equivalent measured at each point on the front surface of the progressive power spectacle lens with the at least one of the front surface coating or the back surface coating and the spherical equivalent measured at each corresponding point on the front surface of a comparison progressive power spectacle lens without the front surface coating and without the back surface coating but with an identical substrate is less than a value from the group specified below:
• (a) the difference value is less than 0.001 dpt
• (b) the difference value is less than 0.002 dpt
• (c) the difference value is less than 0.003 dpt
• (d) the difference value is less than 0.004 dpt
• and wherein
• (c) the refractive index varies in a first spatial dimension and in a second spatial dimension and in a third spatial dimension, wherein a distribution of the refractive index has no point symmetry and no axial symmetry at all.

A computer-implemented method for designing a progressive power spectacle lens having a front surface, a back surface, and a spatially varying refractive index, wherein at least one of the front surface or the back surface is configured as a progressive surface, the method comprising:

• calculating optical properties of the progressive power spectacle lens with a ray tracing method at a plurality of evaluation points, at which visual rays pass through the progressive power spectacle lens;
• setting at least one intended optical property for the progressive power spectacle lens at the respective evaluation point;
• setting a design for the progressive power spectacle lens, wherein the design includes a representation of a local surface geometry of the progressive surface and a local refractive index of the progressive power spectacle lens in the respective visual beam path through the evaluation points;
• modifying the design of the progressive power spectacle lens in view of an approximation of the at least one intended optical property of the progressive power spectacle lens, wherein the modifying includes modifying the representation of the local surface geometry of the progressive surface and the local refractive index of the progressive power spectacle lens in the respective visual beam path through the evaluation points, wherein the at least one intended optical property includes an intended residual astigmatism of the progressive power spectacle lens, wherein the progressive surface and the local refractive index are modified according to at least one of the specifications from the following group of specifications:
• (i) the progressive surface is modified freely in two spatial dimensions and the local refractive index is modified freely in at least two spatial dimensions,
• (ii) the progressive surface is modified freely in one or in two spatial dimensions and the local refractive index is modified freely in three spatial dimensions,
• (iii) the progressive surface is modified freely in two spatial dimensions and the local refractive index is modified freely in two spatial dimensions, and
• (iv) the progressive surface is modified freely in two spatial dimensions and the local refractive index is modified freely in three spatial dimensions.