Method for inkjet printing ophthalmic lens

Abstract

A computer-implemented method for generating print instructions for inkjet printing an ophthalmic lens, the print instructions being based on a digital twin of the ophthalmic lens, the digital twin being sliced into a stack of layers, the method comprising the steps of: (i) generating print instructions for inkjet printing of the ophthalmic lens based on positioning of discrete xm, ym, zm... xn, yn, zn positions of adjacent layers of the stack of layers, positioning volume elements in discrete xm + 1, ym + 1, zm + 1,... xn + 1, yn + 1, zn + 1 positions of layers in the stack of layers; or (ii) based on the positioning of discrete xm, ym, zm... xn, yn, zn positions of the volume elements in adjacent layers in the layer stack, not positioning the volume elements in discrete xm + 1, ym + 1, zm + 1... xn + 1, yn + 1, zn + 1 positions of layers in the layer stack.

Description

[0001] The present invention relates to a computer-implemented method for calculating a digital twin of an ophthalmic lens according to the preamble of claim 1 , alternatively according to the preamble of claim 8 , further alternatively according to the preamble of claim 15 . Background Art

[0002] In order to realize a curved ophthalmic lens according to ISO 13666:2019 (E) section 3.6.2 (curved lenses), i.e. an ophthalmic lens with one surface being convex in all meridians (3.2.11) and another surface being concave in all meridians (3.5.2), a plurality of layers are, for example, inkjet printed in layers, whereby the spatial extension of the plurality of layers in the x,y direction successively increases or decreases in the z direction. The increase or decrease in the spatial extension of the plurality of layers is visible as a step both in plan view and in side view, in particular on the surface of the curved lens which is not in contact with a substrate, which is used, for example, as a removable support material. An additional processing step is usually required, such as polishing to remove the step or applying a further layer to compensate for the step. For example, if in order to realize a convex spherical surface of a spectacle lens (such as a spherical surface as defined in Section 3.4.1 of ISO 13666:2019(E), such as a spectacle lens as defined in Section 3.5.2 of ISO 13666:2019(E)), a plurality of circular layers are inkjet printed in layers, and the radius determining the circumference of each of the plurality of circular layers decreases in the z direction from one inkjet-printed circular layer to the top inkjet-printed circular layer. Considering a circular layer of the plurality of circular layers individually, the circular layer can be a continuous circular layer or a discontinuous circular layer. In the continuous circular layer, the entire circular area is inkjet printed. In the discontinuous circular layer, the area between the radius determining the circumference of the circular layer (the radius is a first radius) and a second radius smaller than the first radius is inkjet printed. Further, in the discontinuous circular layer, the area defined by the second radius is not inkjet printed. Likewise, due to the sequential reduction of the first radius in the plurality of circular layers stacked in the z-direction, the front surface and / or the back surface of the ophthalmic lens exhibits visible steps in plan view and in side view. These visible steps need to be removed in an additional processing step, for example by polishing the respective surface showing the steps, or by applying another layer to compensate for the steps. The respective surface may be a surface that is not in contact with a substrate used as, for example, a removable support material.

[0003] WO 2020 / 165439 A1 discloses a refractive optical component and an eyeglass lens made thereof. An additive manufacturing method is proposed, in which material can be applied dropwise, and the size and / or application density of individual droplets can vary within a single layer.

[0004] WO 2021 / 209551 A1 discloses a method for printing a three-dimensional optical structure built up from layers, in which the printing ink is deposited by targeted placement to match the calculated thickness and lateral dimensions of the respective layer.

[0005] Problem to be solved

[0006] Starting from the above-mentioned disadvantages (obtaining steps on the surface of the inkjet-printed lens), and in particular from WO 2021 / 209551 A1, page 3, lines 4 to 19 (which discloses the placement of droplets according to a dithering pattern during printing of a layer, thereby uniformly or non-uniformly reducing the number of droplets to be placed in a portion of the layer), the purpose of the present invention, like WO 2021 / 209551 A1, is to provide the possibility of avoiding the formation of steps on the surface of the lens, thereby avoiding additional processing steps to remove or compensate for those steps, and in particular to provide a specific dithering algorithm for droplet placement. Summary of the invention

[0007] This problem has been solved by a computer implemented method according to claim 1 , alternatively by a computer implemented method according to claim 8 , further alternatively by a computer implemented method according to claim 15 .

[0008] The dependent claims list preferred embodiments which can be implemented in isolation or in any arbitrary combination.

[0009] In the computer-implemented method, the computer-implemented method is configured for computing a digital twin of an ophthalmic lens for use in the manufacture of the ophthalmic lens, the digital twin comprising a layer stack, the method being characterized in that one of the following conditions applies:

[0010] - When the discrete x of adjacent layers in the layer stack m ,y m ,z m ……x n ,y n ,z n If 50% or less of the positions have volume elements positioned therein, no volume elements are positioned at the discrete x positions of the layers in the layer stack. m+1 ,y m+1 ,z m+1 ……x n+1 ,yn+1 ,z n+1 The position of the layer is discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The position and the corresponding discrete x of the adjacent layer m ,y m ,z m ……x n ,y n ,z n Positioned directly adjacent to and on top of;

[0011] - When the discrete x of adjacent layers in the layer stack m ,y m ,z m ……x n ,y n ,z n If more than 50% of the positions have volume elements positioned, the volume elements are positioned at at least one of the following positions:

[0012] ○ The discreteness x of the layers in the layer stack m+1a……z ,y m+1a……z ,z m+1a……z ……x n+1a……z ,y n+1a……z ,z n+1a……z The position of the layer is discrete x m+1a……z ,y m+1a……z ,z m+1a……z ……x n+1a……z ,y n+1a……z ,z n+1a……z The corresponding discrete position x is not located in the adjacent layer m ,y m ,z m ……x n ,y n ,z n On top of the location,

[0013] ○ The discreteness x of the layers in the layer stack m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The position of the layer is discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The position and the corresponding discrete x of the adjacent layerm ,y m ,z m ……x n ,y n ,z n Positioned directly adjacent to and on top of it.

[0014] Preferably, the volume elements are positioned at discrete positions such that each volume element is positioned at a respective discrete position.

[0015] The computer-implemented method is suitable for generating printing instructions for inkjet printing of an ophthalmic lens. The computer-implemented method is suitable for generating printing instructions for inkjet printing of an ophthalmic lens.

[0016] Preferably, in a computer-implemented method for generating printing instructions for inkjet printing an ophthalmic lens, the printing instructions being based on a digital twin of the ophthalmic lens, the digital twin being sliced ​​into a stack of layers, the method comprises the following steps:

[0017] (i) Based on the discrete x of the adjacent layers in the layer stack of volume elements m ,y m ,z m ……x n ,y n ,z n Positioning, positioning the volume element at the discrete x of the layer in the layer stack m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 location; or

[0018] (ii) Based on the discrete x of the adjacent layers in the layer stack of volume elements m ,y m ,z m ……x n ,y n ,z n Positioning, not positioning the volume element at the discrete x of the layer in the layer stack m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Location.

[0019] m, n are indices of corresponding x, y, z positions in a layer in the layer stack, depending on the number of x, y, z positions in the corresponding layer.

[0020] Preferably, the computer-implemented method is characterized by one of the following conditions:

[0021] -When the discrete x m ,y m ,z m ……x n ,y n ,z n If less than 50% of the positions have volume elements positioned, no volume elements are positioned at the discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Each of the positions;

[0022] -When the discrete x m ,y m ,z m ……x n ,y n ,z n If 50% or more of the positions are located with volume elements, the volume elements are partially located at the discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Location.

[0023] Preferably, in a computer-implemented method for generating printing instructions for inkjet printing an ophthalmic lens, the printing instructions being based on a digital twin of the ophthalmic lens, the digital twin being sliced ​​into a stack of layers, the method comprises the following steps:

[0024] (i) Based on the discrete x of the adjacent layers in the layer stack of volume elements m ,y m ,z m ……x n ,y n ,z n Positioning, positioning the volume element at the discrete x of the layer in the layer stack m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 position, the discrete x of the layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The position and the discrete x of the adjacent layer m ,y m,z m ……x n ,y n ,z n is located directly adjacent to and on top of it; or

[0025] (ii) Based on the discrete x of the adjacent layers in the layer stack of volume elements m ,y m ,z m ……x n ,y n ,z n Positioning, not positioning the volume element at the discrete x of the layer in the layer stack m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 position, the discrete x of the layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The position and the discrete x of the adjacent layer m ,y m ,z m ……x n ,y n ,z n Located directly adjacent to and on top of it,

[0026] Characterized in that one of the following conditions applies:

[0027] -When the discrete x in the adjacent layer m ,y m ,z m ……x n ,y n ,z n If 50% or less of the positions have volume elements positioned, no volume elements are positioned at the discrete x position of the layer. m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Location;

[0028] -When the discrete x in the adjacent layer m ,y m ,z m ……x n ,y n ,z nIf more than 50% of the positions are located with volume elements, then the volume elements are partially located at the discrete x of the layer. m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Location.

[0029] When the discrete x in the adjacent layer m ,y m ,z m ……x n ,y n ,z n If less than 50% of the positions have already been positioned with volume elements, no volume elements will be positioned at the discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Position, which means that in two adjacent layers, the volume elements are not directly adjacent and are not positioned above each other. Instead, the volume elements are positioned at discrete x m+1a ,y m+1a ,z m+1a ……x n+1a ,y n+1a ,z n+1a position, so that it is not located in the discrete x m ,y m ,z m ……x n ,y n ,z n The top of the volume element of the location.

[0030] When the discrete x in the adjacent layer m ,y m ,z m ……x n ,y n ,z n If volume elements are already located at 50% or more of the positions, the volume element is located at the discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Position or not position the volume element at discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 position, which means that when the discrete x in the adjacent layerm ,y m ,z m ……x n ,y n ,z n When a volume element is already located at the position, preferably, in the first step, the volume element is not located at the discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Instead, the volume elements are positioned at discrete x m+1a ,y m+1a ,z m+1a ……x n+1a ,y n+1a ,z n+1a position, so that it is not located at the discrete x positioned in the adjacent layer m ,y m ,z m ……x n ,y n ,z n The top of the volume element at the position. m+1a ,y m+1a ,z m+1a ……x n+1a ,y n+1a ,z n+1a If there are volume elements at all positions, then in the second step, the volume elements are located at the discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 position. It is not necessary to have m+1a ,y m+1a ,z m+1a ……x n+1a ,y n+1a ,z n+1a After all the volume elements are located, the volume elements are started in the discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Preferably, when the discrete x m+1a ,y m+1a ,z m+1a ……x n+1a ,y n+1a ,z n+1aWhen positioning the volume elements, the maximum distance between two volume elements is taken into account. The maximum distance preferably corresponds to the maximum distance between two single ink droplets, which allows the two single ink droplets to coalesce in the inkjet-printed layer, thereby ensuring a continuous inkjet-printed layer. Preferably, when (i) at discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 position or (ii) at a discrete x m+1a ,y m+1a ,z m+1a ……x n+1a ,y n+1a ,z n+1a When positioning the volume elements, the variation of the distance between two adjacent volume elements in the layer is minimized. The layered inkjet printing of the ophthalmic lens preferably enables the surface or interface of the layer to be as smooth as possible while taking into account the minimized variation of the distance between two adjacent ink droplets in the layer. Preferably, the adjacent volume elements are positioned so that the variation of the distance between adjacent volume elements is less than 50%, preferably less than 25%.

[0031] "Generating" a print instruction comprises the following steps, preferably in the order given:

[0032] a) Slicing the digital twin of the eyeglass lens into a stack of layers. Preferably, the digital twin is sliced ​​into interfaces of layers in the stack of layers or the forms of interfaces of layers in the stack of layers are each a linear combination of the surface forms of the front surface and the surface forms of the back surface of the digital twin. Preferably, for slicing, a maximum layer thickness of each layer in the stack of layers is preset, the maximum layer thickness is preferably determined by the maximum layer thickness that can be inkjet printed with a single ink drop. Further preferably, for the determination of the maximum layer thickness, the positioning of adjacent ink drops in the same layer in the stack of layers within a minimum distance from the single ink drop is taken into account. The positioning of adjacent ink drops within the minimum distance preferably prevents the single ink drop from spreading completely. Preferably, the minimum distance is preset by the printing resolution of the inkjet printer, preferably by the printing resolution of the inkjet print head of the inkjet printer. Preferably, for slicing, a minimum layer thickness of each layer in the stack of layers is preset, the minimum layer thickness is preferably determined by the minimum layer thickness that still produces a continuous layer. Further preferably, for said determination of said minimum layer thickness a maximum distance of two single ink drops inkjet printed in the same layer in said layer stack is taken into account. Said maximum distance of said two single ink drops is the maximum distance which allows said two single ink drops to coalesce. Due to said coalescence a continuous layer can be inkjet printed.

[0033] Preferably, slicing ensures knowledge of the layer thickness at each discrete x,y,z position of each layer in the layer stack. Positioning of ink drops within a minimum distance, preferably according to the printing resolution of an inkjet printer, further preferably according to the printing resolution of an inkjet print head of an inkjet printer, or positioning of ink drops within a maximum distance is a supporting tool for slicing the digital twin of the eyeglass lens into a layer stack. Preferably, the eyeglass lens is inkjet printed with the inkjet printer. Additionally or alternatively, knowledge of the thickness of the digital twin (i.e. the center thickness, the edge thickness, and the thickness between the center thickness and the edge thickness for each discrete x,y,z position, preferably the distance between the front surface and the back surface of the digital twin for each discrete x,y,z position) supports slicing the digital twin of the eyeglass lens into a layer stack. Analogously to the definition given in section 3.2.47 of ISO 13666:2019(E), the center thickness of the digital twin shall refer to the thickness of the digital twin of the ophthalmic lens at its reference point, determined normal to the front surface of the digital twin. Analogously to the definition given in section 3.2.19 of ISO 13666:2019(E), the reference point of the digital twin shall correspond to the point on the front surface of the inkjet printed finished ophthalmic lens, for which the validation power of a specific portion is applicable. Analogously to the definition given in section 3.2.48 of ISO 13666:2019(E), the edge thickness shall refer to the thickness at a point on the edge of the digital twin of the ophthalmic lens. The layer thickness at each corresponding x,y,z position of an inkjet printed layer depends on the density of ink droplets in the layer: the more ink droplets are positioned within an area element, the higher the layer thickness in the area element. The area element is preferably preset to include more than ten discrete locations for ink drops within the layer, i.e., more than ten locations where (i) ink drops are placed or (ii) ink drops can be placed but are not placed. Preferably, when projected in a plane defined by the x-direction and the y-direction, the area element may have an area of, for example, 100 discrete locations for ink drops, ten in the x-direction and ten in the y-direction. In other words, in an inkjet-printed layer, the layer thickness is defined as the number of ink drops multiplied by the volume of the ink drops divided by the area of ​​the area element:

[0034]

[0035] Preferably, the thickness of the digital twin (i.e., the center thickness, the edge thickness, and the thickness between the center thickness and the edge thickness at each discrete x,y position, preferably the distance between the front surface and the back surface of the digital twin at each discrete x,y,z position) is reflected in the thickness distribution of the layers in the layer stack, preferably in the thickness distribution of each layer in the layer stack except the base layer. Reflecting the thickness distribution should mean that the ratio of the thickness of the digital twin between two discrete x,y,z positions is the same as the ratio of the layers in the layer stack (preferably except the base layer) at two discrete x,y,z positions that have the same z position as the two discrete x,y,z positions of the digital twin.

[0036] Preferably, according to the aforementioned restrictions on minimum layer thickness or maximum layer thickness, the digital twin is sliced ​​to include the maximum number of layers in the layer stack. According to the aforementioned restrictions on minimum layer thickness or maximum layer thickness, the digital twin can also be sliced ​​to include a reasonable number of layers in the layer stack. The reasonable number of layers can be a compromise between the possible maximum number of layers and the possible minimum number of layers in the layer stack. The possible maximum number of layers mainly contributes to achieving a predefined focal length, while the possible minimum number of layers mainly contributes to avoiding appearance defects when the corresponding eyeglass lens is layered inkjet printed;

[0037] b) converting each layer in the layer stack into a spatial volume element pattern. In the spatial volume element pattern, each volume element is positioned at a discrete x, y, z position. In the spatial volume element pattern, each volume element represents an ink drop. In the spatial volume element pattern, volume elements serve as virtual placeholders for ink droplets. In the spatial volume element pattern, when the layered inkjet printing of the eyeglass lens, each volume element positioned at a discrete x, y, z position serves as a virtual placeholder for each ink droplet to be positioned at a corresponding discrete x, y, z position of the eyeglass lens. Each volume element is a computer-readable representation of the digital positioning of an ink droplet at a discrete x, y, z position in the spatial volume element pattern of the digital twin of the eyeglass lens. Preferably, in order to convert the digital twin into the spatial volume element pattern, the printing resolution of the inkjet printer, preferably the printing resolution of the inkjet print head of the inkjet printer, is taken into account;

[0038] c) converting the spatial volume element pattern into a printing instruction, when the printing instruction is executed by an inkjet printer, the printing instruction causes the inkjet printer to print the eyeglass lens in layers. Preferably, the sliced ​​spatial volume element pattern is converted into a printing instruction, when the printing instruction is executed by an inkjet printer, the printing instruction causes the inkjet print head of the inkjet printer to release a jet at a corresponding discrete x, y, z position in the layer to form ink droplets. Preferably, the printing instruction is computer-readable data, which includes an image stack (one image for each layer to be inkjet printed, such as a tiff image) and a text file in, for example, .xml format. The text file preferably includes instructions for the inkjet printing sequence of the image stack corresponding to the layer stack. The text file preferably further includes process parameters required for inkjet printing the eyeglass lens in layers, such as fixing the power of the LED-cured ink droplets (the ink droplets preferably include a UV-curable fluid) and raising the z position of the inkjet print head after the layer has been inkjet printed to avoid collision between the inkjet print head and the inkjet-printed layer.

[0039] When inkjet printing an eyeglass lens in layers, when an ink droplet is positioned according to a discrete x,y,z position of a volume element in the spatial volume element pattern of the digital twin of the eyeglass lens, the discrete x,y,z position of the volume element in the spatial volume element pattern of the digital twin of the eyeglass lens “corresponds” to the discrete x,y,z position of the ink droplet. The ink droplet is positioned at that position in the spatial volume element pattern at which its discrete positioning is intended to be achieved. Similarly, when inkjet printing an eyeglass lens in layers, when an ink droplet is positioned at that discrete x,y,z position in the spatial volume element pattern of the digital twin where a volume element has been used as a virtual representation or virtual placeholder, the discrete x,y,z position of the ink droplet “corresponds” to the discrete x,y,z position of the volume element in the spatial volume element pattern of the digital twin of the eyeglass lens.

[0040] The digital twin of the eyeglass and the “discrete x, y, z position” or “multiple discrete x, y, z positions” of the eyeglass are both included in an x, y, z coordinate system. The x, y, z coordinate system is preferably defined as follows:

[0041] The surface normal at the vertex of the front surface of the digital twin of the eyeglass or the vertex of the back surface of the digital twin of the eyeglass shall define the origin and z direction of the x,y,z coordinate system. The surface normal at the vertex of the front surface of the eyeglass or the vertex of the back surface of the eyeglass shall define the origin and z direction of the x,y,z coordinate system. The x,y directions shall lie in the tangent plane of the front surface at the corresponding vertex or the back surface at the corresponding vertex. The x direction and the y direction shall be perpendicular to each other in the corresponding tangent plane.

[0042] Instead of the surface normal at the corresponding vertex of the front surface or instead of the surface normal at the corresponding vertex of the back surface, a) the optical center of the digital twin of the lens or b) the optical center of the lens can each define the origin of the x, y, z coordinate system, and the surface normal at the corresponding optical center can define the z direction. The x, y directions are then in a tangential plane that intersects the corresponding front surface. In the corresponding tangential plane, the x direction and the z direction are perpendicular to each other. Similar to ISO 13666:2019(E) section 3.2.15, the optical center of the digital twin of the lens is defined as the intersection of the optical axis and the front surface of the digital twin. As in ISO 13666:2019(E) section 3.2.15, the optical center of the lens is defined as the intersection of the optical axis (3.1.8) and the front surface (3.2.13) of the lens (3.5.2).

[0043] If a) the front or back surface of the digital twin of the spectacle lens or b) the front or back surface of the spectacle lens is, for example, a power variation surface or another surface without a clearly definable vertex, the surface normals at a) the digital twin of the spectacle lens or b) the fitting point of the spectacle lens shall preferably each define the origin of an x, y, z coordinate system and the principal direction may define the z direction. Analogously to ISO 13666:2019(E) section 3.2.25, the principal direction of the digital twin of the spectacle lens is defined as the direction of a virtually represented line of sight (generally considered to be horizontal) to an object at infinite distance as assumed with a habitual head and body posture when looking straight ahead under unaided vision. As in ISO 13665:2019(E) section 3.2.25, the principal direction of the spectacle lens is defined as the direction of the line of sight (3.2.24) to an object at infinite distance as measured with a habitual head and body posture when looking straight ahead under unaided vision (generally considered to be horizontal). In this case, the x, y directions are in a plane perpendicular to the respective main direction. In the respective plane perpendicular to the respective main direction, the x direction and the y direction are perpendicular to each other.

[0044] "Printing instructions" are computer readable data which, when executed by an inkjet printer, cause the inkjet printer to inkjet print an eyeglass lens.

[0045] The printing instructions are preferably based on computer readable data of the sliced ​​digital twin of the ophthalmic lens.

[0046] The printing instructions are preferably in the form of computer-readable data and are based on the sliced ​​digital twin of the ophthalmic lens; when the printing instructions are executed by the inkjet printer, the printing instructions cause the inkjet printer to inkjet print the ophthalmic lens.

[0047] The printing instructions as or in the form of computer readable data are preferably (i) stored on a computer readable storage medium or (ii) transmitted via a data signal.The computer readable storage medium may be a non-transitory tangible computer readable storage medium.

[0048] The printing instructions are preferably configured to cause the inkjet printer to inkjet print the ophthalmic lens when executed by the inkjet printer. The printing instructions are preferably computer readable data, which when executed by the inkjet printer are configured to cause the inkjet printer to inkjet print the ophthalmic lens in layers, wherein, starting from a base layer directly adjacent to an optionally removable substrate, in each layer, ink drops are positioned at discrete x, y, z positions. The discrete x, y, z positions of the ink drops positioned in the layers to inkjet print the ophthalmic lens preferably correspond to discrete x, y, z positions of volume elements in a spatial volume element pattern of a digital twin of the ophthalmic lens to be inkjet printed.

[0049] The purpose of the printing instructions is for inkjet printing an eyeglass lens. The printing instructions are computer readable data, the purpose of the data is to inkjet print an eyeglass lens in layers. Inkjet printing the eyeglass lens preferably starts with inkjet printing a base layer directly in or on an optionally removable substrate, continuing with inkjet printing in layers until the eyeglass lens is finally inkjet printed. The location of the discrete x, y, z position of each ink droplet in each layer is specified by the corresponding discrete x, y, z position of the volume element in the spatial volume element pattern of the digital twin of the eyeglass lens to be inkjet printed.

[0050] Preferably, when the printing instructions are executed by an inkjet printer, the printing instructions cause a print head of the inkjet printer to release a jet at a corresponding discrete x, y, z position in the layer to form ink drops.

[0051] The substrate on or in which the base layer is inkjet printed or to which the base layer is directly adjacent may be removable from the inkjet printed ophthalmic lens or may remain on the inkjet printed ophthalmic lens.Preferably, the ophthalmic lens and the substrate are removable from each other.

[0052] Preferably, the printing instructions are in a computer readable data format, which includes an image stack (one image for each layer to be inkjet printed, such as a tiff image) and a text file in, for example, .xml format, as described above.

[0053] A "spatial volume element pattern" is a digital representation of the volume elements of each layer of a sliced ​​digital twin of an eyeglass lens or a virtual description of the volume elements. The digital representation or the virtual description is preferably computer-readable data or in the form of computer-readable data. The computer-readable data may be (i) stored on a computer-readable storage medium or (ii) transmitted via a data signal. The computer-readable storage medium may be a non-transitory tangible computer-readable storage medium. In the spatial volume element pattern, each volume element is spatially positioned at a discrete x, y, z position. In the spatial volume element pattern, each volume element at a discrete x, y, z position represents an ink droplet to be positioned at a corresponding discrete x, y, z position when inkjet printing the eyeglass lens.

[0054] Similar to ISO 13666:2019(E) Section 3.5.2 (Spectacle lenses), a "digital twin" of a spectacle lens is defined as a digital twin of an ophthalmic lens (3.5.1) that, when converted into a physical entity, is worn in front of the eyeball but not in contact with the eyeball. The digital twin of the spectacle lens may include the design of the spectacle lens, preferably based on an ordered power as defined in ISO 13666:2019(E) Section 3.10.14. The purpose of the digital twin of the spectacle lens is for manufacturing spectacle lenses, in particular for inkjet printing spectacle lenses.

[0055] In order to provide a specific jitter algorithm, the digital twin of the eyeglass is preferably a mathematical description of the lens surface of the front surface of the eyeglass, a mathematical description of the lens surface of the back surface of the eyeglass, the mathematical description optionally including (i) a refractive index for the eyeglass or (ii) a refractive index distribution n(x, y, z) for the eyeglass. The lens surface of the digital twin is defined similarly to Section 3.4 of ISO 13666:2019 (E). Similar to Section 3.2.13 of ISO 13666:2019 (E), the front surface of the digital twin of the eyeglass is defined as the surface intended to be away from the eye assembly when the digital twin is converted into a physical entity. Similar to Section 3.2.14 of ISO 13666:2019 (E), the back surface of the digital twin of the eyeglass is defined as the surface intended to be closer to the eye assembly when the digital twin is converted into a physical entity. The refractive index of the eyeglass is the refractive index that the eyeglass should have after it has been inkjet printed. The refractive index profile of the ophthalmic lens is the refractive index profile that the ophthalmic lens should have after having been inkjet printed. Preferably, the mathematical description of the lens surface of the front surface and the back surface comprises the relative orientation of the front surface and the back surface with respect to each other, e.g. in the same coordinate system, and a) one refractive index of the ophthalmic lens or b) a plurality of refractive indices of the ophthalmic lens. Instead of comprising the relative orientation of the front surface and the back surface in the same coordinate system, the mathematical description may comprise the relative orientation of the front surface and the back surface and the distance between the front surface and the back surface, preferably in an arbitrarily selected point on one of these surfaces.

[0056] The digital twin of the eyeglass lens is a mathematical description or a mathematical representation of the lens surface of the eyeglass lens, optionally including a refractive index or optionally including a refractive index distribution n(x, y, z), the mathematical description or the mathematical representation being computer readable data or in the form of computer readable data. The computer readable data may be (i) stored on a computer readable storage medium or (ii) transmitted via a data signal. The computer readable storage medium may be a non-transitory tangible computer readable storage medium. The computer readable data may additionally include printing instructions for inkjet printing the eyeglass lens. The computer readable data may additionally include printing instructions, which, when executed by an inkjet printer, cause the inkjet printer to inkjet print the eyeglass lens.

[0057] Additionally or alternatively, for the use of a digital twin for manufacturing an eyeglass lens, in particular for inkjet printing an eyeglass lens, the digital twin of the eyeglass lens may be one of the following:

[0058] - an analytical description or an analytical model describing or representing the spectacle lens. The analytical description or the analytical model is preferably a piecewise description or a piecewise representation and comprises (i) a mathematical formula describing the lens surface of the front surface of the digital twin of the spectacle lens and (ii) a mathematical formula describing the lens surface of the back surface of the digital twin of the spectacle lens and optionally (iii) a mathematical formula describing a refractive index of the spectacle lens or describing a plurality of refractive indices of the spectacle lens, the relative orientation of the front surface with respect to the back surface as described above preferably being included in the analytical description or the analytical model;

[0059] - an analytical description or an analytical model describing or representing the ophthalmic lens, the analytical description or the analytical model additionally comprising printing instructions for (i) inkjet printing the ophthalmic lens or (ii) causing an inkjet printer to inkjet print the ophthalmic lens when executed by an inkjet printer;

[0060] - in the form of an analytical description or an analytical model representing said ophthalmic lens;

[0061] - in the form of an analytical description or an analytical model representing the ophthalmic lens, the analytical description or the analytical model additionally comprising printing instructions for (i) inkjet printing the ophthalmic lens or (ii) causing an inkjet printer to inkjet print the ophthalmic lens when executed by an inkjet printer;

[0062] - the analysis description or the analysis model is (i) stored on a computer-readable storage medium or (ii) transmitted via a data signal. The computer-readable storage medium may be a non-transitory tangible computer-readable storage medium;

[0063] - numerical data describing or representing said ophthalmic lens. The numerical data preferably comprises or is a transformation of said analytical description or said analytical model. The numerical data preferably comprises a pattern comprising discrete z-values ​​of or on the front surface of said digital twin of said ophthalmic lens. 前 (x, y) position and the discrete z of the rear surface or on the rear surface of the digital twin of the eyeglass 后 (x,y) position. The discrete z 前 (x,y) position and the discrete z 后 The (x, y) position preferably takes into account the printing resolution of the inkjet printer, preferably the printing resolution of the inkjet print head of the inkjet printer. 前 (x,y) position and the discrete z 后The lens surface is described by a mathematical formula for each of the (x, y) positions. Thus, the numerical data comprises an analytical description or an evaluation of an analytical model for the lens surface in each of the discrete x, y positions, preferably meaning that the numerical data comprises the function values ​​of the analytical description or analytical model of the lens surface of at least one of the front surface and the back surface at each discrete x, y position. The function values ​​of the lens surface of the front surface and the back surface in each discrete x, y position (i.e. discrete x, y, z position) are preferably described in the same coordinate system; alternatively, the relative orientation of the front and back surfaces, e.g. of the coordinate system, and the distance between the front and back surfaces (preferably in an arbitrarily selected point on one of these surfaces) are included in the numerical data. Optionally, a refractive index or a refractive index distribution is included in the numerical data, the refractive index distribution comprising a pattern comprising (i) discrete x, y, z positions (n(x, y, z)) of or on the front surface of the digital twin of the lens, (ii) discrete x, y, z positions (n(x, y, z)) of or on the back surface of the digital twin of the lens, and (iii) discrete x, y, z positions (n(x, y, z)) between the front surface and the back surface. Preferably, the numerical data is used as a basis for slicing. When the numerical data is used as a basis for slicing, less computing power is required than when the analytical description or the analytical model is used as a basis for slicing. In other words, slicing the numerical data is computationally less expensive;

[0064] - numerical data describing or representing the ophthalmic lens, the numerical data additionally comprising printing instructions for (i) inkjet printing the ophthalmic lens or (ii) causing an inkjet printer to inkjet print the ophthalmic lens when executed by an inkjet printer;

[0065] - in the form of numerical data describing or representing said ophthalmic lens;

[0066] - in the form of numerical data describing or representing said ophthalmic lens, said numerical data additionally comprising printing instructions for (i) inkjet printing said ophthalmic lens or (ii) causing an inkjet printer to inkjet print said ophthalmic lens when executed by an inkjet printer;

[0067] - the numerical data is (i) stored on a computer-readable storage medium or (ii) transmitted via a data signal. The computer-readable storage medium may be a non-transitory tangible computer-readable storage medium;

[0068] - computer readable data describing or representing said ophthalmic lens;

[0069] - computer readable data describing or representing the ophthalmic lens, the computer readable data additionally comprising printing instructions for (i) inkjet printing the ophthalmic lens or (ii) causing an inkjet printer to inkjet print the ophthalmic lens when executed by an inkjet printer;

[0070] - in the form of computer-readable data describing or representing said ophthalmic lens;

[0071] - in the form of computer-readable data describing or representing said ophthalmic lens, said computer-readable data additionally comprising printing instructions for (i) inkjet printing said ophthalmic lens or (ii) causing an inkjet printer to inkjet print said ophthalmic lens when executed by an inkjet printer;

[0072] - The computer readable data is (i) stored on a computer readable storage medium or (ii) transmitted via a data signal. The computer readable storage medium may be a non-transitory tangible computer readable storage medium.

[0073] As defined in section 3.5.2 of ISO 13666:2019(E), a “spectacle lens” or lens is an ophthalmic lens that is worn in front of the eye but not in contact with the eye.

[0074] As defined in ISO 13666:2019(E) section 3.2.13, the front surface is the surface of the lens (3.5.2) that is intended to fit away from the eye. As defined in ISO 13666:2019(E) section 3.2.14, the back surface is the surface of the lens (3.5.2) that is intended to fit closer to the eye.

[0075] In the context of the present invention, further, the spectacle lens is a physical representation of a corresponding digital twin of the spectacle lens, and the spectacle lens is an inkjet-printed physical representation of the corresponding digital twin. The spectacle lens is produced by converting the digital twin of the spectacle lens into a physical entity.

[0076] "Slicing" is the conversion of a digital twin of an eyeglass lens into a stack of layers. Preferably, slicing is the conversion of the digital twin digitally represented by numerical data (numerical data as defined above) into a stack of layers. Slicing is the digital conversion of the digital twin into a stack of layers, wherein the layer thickness is preset for each layer. The layer thicknesses are digitally preset in the center of the layer, in the edges of the layer and between each x, y, z position of the layer. Preferably, each layer in the stack of layers has the same spatial extension in a plan view when projected in a plane determined by the x-direction and the y-direction.

[0077] "Location" is the digital placement or virtual arrangement or digital distribution of volume elements at discrete x, y, z locations for each layer in the layer stack of the sliced ​​digital twin of the ophthalmic lens. Positioning volume elements at discrete x, y, z locations preferably includes (i) digital placement or virtual arrangement within a layer and (ii) digital placement or virtual arrangement in an adjacent layer, in an alternate layer, in a layer adjacent to the alternate layer, and so on. Preferably, the positioning is digital placement of a single volume element at each discrete x, y, z location.

[0078] Discretization of volume elements in layers x +1 ,y +1 ,z +1 The positioning of the position depends on or is based on the positioning of volume elements in an adjacent layer at discrete x, y, z positions. In the adjacent layer, each volume element is positioned at a discrete x, y, z position. In the adjacent layer, preferably when projected in a plane defined by the x-direction and the y-direction, in a plan view, each volume element has a discrete x, y, z position. In the layer, preferably when projected in a plane defined by the x-direction and the y-direction, in a plan view, each volume element has a discrete x, y, z position when it is directly adjacent to and located on top of a volume element having a discrete x, y, z position in the adjacent layer. +1 ,y +1 ,z +1 The layer and the adjacent layer are stacked in the z direction. The z direction is perpendicular to the plane defined by the x direction and the y direction.

[0079] When positioning volume elements in a layer, the volume elements of a first adjacent layer are digitally placed, and further digital placement of volume elements depends on the positioning of volume elements of the first adjacent layer. After the digital placement of these volume elements, these volume elements then form the basis for the second adjacent layer, and further digital placement of further volume elements depends on the positioning of volume elements of the second adjacent layer. These digitally placed volume elements in turn form the basis for a third adjacent layer, and further digital placement of further volume elements depends on the positioning of volume elements of the third adjacent layer. The positioning in the layer is repeated until the volume elements in the final layer are digitally placed depending on the positioning of volume elements of the adjacent layer below it.

[0080] Do not position volume elements at discrete x of the layer +1 ,y +1 ,z +1 The position depends on or is based on the positioning of volume elements in adjacent layers at discrete x, y, z positions. In the adjacent layers, each volume element (i) is positioned at a discrete x, y, z position or (ii) is not positioned at a discrete x, y, z position. Regarding the non-positioning, the explanations given above for positioning also apply.

[0081] The digital twin of the ophthalmic lens is sliced ​​into a layer stack. The layer stack comprises a plurality of layers. Preferably, the layer stack comprises up to 200 stacked layers, further preferably up to 150 stacked layers. Further preferably, the layer stack comprises between 50 and 130 stacked layers, further preferably between 60 and 120 stacked layers, more preferably between 70 and 115 stacked layers, most preferably between 80 and 110 stacked layers. Preferably, for slicing the digital twin of the ophthalmic lens, the printing resolution of an inkjet printer, preferably an inkjet print head of the inkjet printer, used for inkjet printing the ophthalmic lens is taken into account.

[0082] In the layer stack, the volume element:

[0083] (i) It depends on the volume elements in the adjacent layers at discrete x m ,y m ,z m ……x n ,y n ,z n Positioning, positioning (i.e., digitally placing or virtually arranging or digitally distributing) of discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 position, when both the layer and the adjacent layer are projected in a plane defined by the x-direction and the y-direction, for example in a plan view, the discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The position and the discrete x of the adjacent layer m ,y m ,z m ……x n ,y n ,z n is located directly adjacent to and on top of it, or

[0084] (ii) It depends on the volume elements in the adjacent layers at the discrete x m ,y m ,z m ……x n ,y n ,z n Positioning, not positioning (i.e., not digitally placing or virtually arranging or digitally distributing) on ​​a discrete x m+1 ,y m+1 ,zm+1 ……x n+1 ,y n+1 ,z n+1 position, when both the layer and the adjacent layer are projected in a plane defined by the x-direction and the y-direction, for example in a plan view, the discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The position and the discrete x of the adjacent layer m ,y m ,z m ……x n ,y n ,z n Positioned directly adjacent to and on top of it.

[0085] When a slice is projected in a plane defined by the x-direction and the y-direction, preferably in a plan view, the volume element has a discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Position. In the layer with discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The volume element at the location has the same discrete x as in the adjacent layer m ,y m ,z m ……x n ,y n ,z n If two volume elements differ only in their z position, the adjacent layers are preferably also in a plan view when projected in a plane determined by the x-direction and the y-direction. In the layer stack, all layers are projected in a plane determined by the x-direction and the y-direction, preferably in a plan view, the volume elements are digitally placed above each other when they have the same x,y position but different z positions. Digitally placed above each other means that in the layer z m+1 , a layer of z m+2 , and the layer z adjacent to the next layer m+3 (and so on). The numerical placement above and below each other does not mean that m+1 , a layer of z m+2 , and the layer z adjacent to the next layer m+3A volume element is digitally placed in each of the layers (and so on), and the volume element can be placed in any layer in the layer stack at z m Positions are placed numerically above and below each other, but do not need to be placed in the z of each layer m Position. If the volume element is not digitally placed in layer z m+1 Instead, place it in a layer of m+2 or placed in the layer adjacent to the next layer. m+3 In (and so on), the volume elements and the numbers are placed at z m Volume elements of a position are above and below each other but not adjacent to each other when they have the same x,y position.

[0086] Positioning or not positioning "a" volume element at a discrete x, y, z position of the corresponding layer preferably includes positioning or not positioning multiple volume elements at different discrete x, y, z positions of the corresponding layer, preferably each discrete x, y, z position has one volume element of the multiple volume elements or no volume element positioned.

[0087] In the layer stack, the positioning of the volume elements preferably starts with the digital placement of the volume elements in a base layer. The base layer is preferably a digital representation of a layer directly adjacent to the substrate. The base layer is preferably a digital representation of a layer inkjet printed in or on the substrate. In the base layer, when projected in a plane determined by the x-direction and the y-direction, preferably in a plan view, a volume element is digitally placed at each discrete x, y, z position of the base layer. When projected in a plane determined by the x-direction and the y-direction, preferably in a plan view, the base layer has a constant thickness. In the layer stack, the positioning of the volume elements ends with the digital placement of the volume elements in a final layer. In an inkjet-printed ophthalmic lens, the base layer is or forms the front surface or the back surface of the ophthalmic lens, and the final layer is or forms the back surface or the front surface of the ophthalmic lens, respectively. Between the base layer and the final layer:

[0088] (i) Position the volume elements at discrete x in the layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Location, or

[0089] (ii) Do not position the volume elements at the discrete x of the layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Location,

[0090] Each depends on or is based on the volume elements in the adjacent layer at discrete x m ,y m ,z m ……x n ,y n ,z n Positioning of location.

[0091] Position or not position the volume element at the discrete x of the layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Position preferably means that a plurality of volume elements are located at different discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Position, a volume element is located or not located at different discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 An x in the position m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The number of volume elements preferably depends on the number of volume elements to be positioned.

[0092] In the layer stack, the:

[0093] (i) Positioning volume elements at discrete x layers adjacent to the base layer or at the first layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 position, when both the layer and the base layer are projected in a plane defined by the x-direction and the y-direction, preferably in a plan view, the discrete x-direction of the layer or the first layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The position corresponds to the base layer x m ,y m ,zm ……x n ,y n ,z n directly adjacent to and located on top of, or

[0094] (ii) not locating volume elements in a discrete x layer adjacent to the base layer or in the first layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 position, when both the layer and the base layer are projected in a plane defined by the x-direction and the y-direction, preferably in a plan view, the discrete x-direction of the layer or the first layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The position corresponds to the base layer x m ,y m ,z m ……x n ,y n ,z n directly adjacent to and located on top of,

[0095] Each depends on or is based on the volume elements in the adjacent base layer at discrete x m ,y m ,z m ……x n ,y n ,z n Positioning of location.

[0096] In the layer stack, the:

[0097] (i) Position the volume element at the next or second discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 position, when both the first layer and the base layer are projected in a plane defined by the x-direction and the y-direction, preferably in a plan view, the discrete x-direction of the first layer or the base layer m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 The corresponding x position is located in the base layer m ,y m ,z m……x n ,y n ,z n on top of, or

[0098] (ii) Do not locate volume elements at the next or second discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 position, when both the first layer and the base layer are projected in a plane defined by the x-direction and the y-direction, preferably in a plan view, the discrete x-direction of the first layer or the base layer m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 The corresponding x position is located in the base layer m ,y m ,z m ……x n ,y n ,z n On top of

[0099] Each depends on or is based on the volume elements in the layer or the first layer at discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The first or second layer is adjacent to the first layer and is one layer away from the base layer.

[0100] In the layer stack, the:

[0101] (i) Locate the volume element at the discrete x layer adjacent to the next layer or the third layer m+3 ,y m+3 ,z m+3 ……x n+3 ,y n+3 ,z n+3 position, when both the layer adjacent to the layer next to the base layer are projected in a plane defined by the x-direction and the y-direction, preferably in a plan view, the discrete x position of the layer adjacent to the layer next to the base layer m+3 ,y m+3 ,z m+3 ……x n+3 ,y n+3 ,z n+3 The position is located at the base layer x m ,y m,z m ……x n ,y n ,z n on top of, or

[0102] (ii) Do not locate volume elements on the discrete x layers adjacent to the next layer or on the third layer. m+3 ,y m+3 ,z m+3 ……x n+3 ,y n+3 ,z n+3 position, when both the layer adjacent to the layer next to the base layer are projected in a plane defined by the x-direction and the y-direction, preferably in a plan view, the discrete x-direction of the layer adjacent to the layer next to the base layer is m+3 ,y m+3 ,z m+3 ……x n+3 ,y n+3 ,z n+3 The position is located at the base layer x m ,y m ,z m ……x n ,y n ,z n On top of

[0103] Each depends on or is based on the volume elements in the first or second layer at the discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 Positioning. The layer or the third layer adjacent to the first or second layer is a layer adjacent to the first or second layer, one layer away from the layer or the first layer, and adjacent to the first layer of the base layer.

[0104] In the layer stack, the steps of (i) positioning the volume element or (ii) not positioning the volume element at discrete x are repeated. m+u ,y m+u ,z m+u ……x n+v ,y n+v ,z n+v positions until the volume elements in the final layer are either (i) positioned or (ii) not positioned.

[0105] (i) Positioning volume elements at discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1position or (ii) not locating the volume element at the discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The positions are determined by or based on the volume elements in the adjacent layers at the discrete x m ,y m ,z m ……x n ,y n ,z n Positioning of the position causes the volume element density to change. Preferably, the change in the volume element density is given in each layer in the layer stack except the base layer. The change in the volume element density in the layer in the layer stack of the sliced ​​digital twin is a digital representation of the change in the ink droplet in the layer. The printing instructions including the change in the volume element density executed by the inkjet printer cause the inkjet printer, preferably the print head of the inkjet printer, to release a jet to form ink droplets according to the change in the layer. The change in the ink droplet in the layer causes the layer thickness of the layer to change. The change in the layer thickness avoids the problem of waviness in inkjet-printed eyeglasses. In contrast to the change in the ink droplet density within a single layer disclosed in WO 2020 / 165439 A1 on page 25, lines 10 to 18 or on page 26, lines 23 to 30, the present invention not only suggests changing the ink droplet density in the layer, but also suggests changing the volume element density in the layer (digitally representing the ink droplet density) based on the positioning of the volume elements in the adjacent layers, so that the volume elements representing the ink droplets are preferably placed complementary to the adjacent layers. This has the decisive advantage that steps on the surface of the inkjet-printed ophthalmic lens, both in plan view and in side view, are avoided. Moreover, residual structures that could affect the optical quality of the ophthalmic lens are minimized in each layer.

[0106] The effect of the aforementioned variation in the density of volume elements in the layers of the digital twin of the ophthalmic lens, resulting from positioning or not positioning volume elements at discrete positions depending on the positioning or not positioning of volume elements at adjacent discrete positions below adjacent layers, is that each layer of the digital twin contributes to the focal power of the digital twin, similar to ISO 13666:2019(E) section 3.1.10, where focal power is defined as the ability of a digital twin of an ophthalmic lens or a virtual representation of an optical surface to compute the curvature or direction of a virtually represented incident wavefront by refraction. The contribution of each layer to the focal power of the digital twin depends on the number of layers into which the digital twin is sliced. Therefore, the contribution of each layer to the focal power of the digital twin is 1 / the number of layers. For example, if the digital twin of the ophthalmic lens is sliced ​​into 100 layers, then each of the 100 layers contributes 1 / 100 to the focal power of the digital twin. Accordingly, in an inkjet-printed ophthalmic lens, the effect of the change in layer thickness corresponding to the change in the density of volume elements in the corresponding layer of the digital twin is that each inkjet-printed layer contributes to the focal power of the ophthalmic lens, as defined in Section 3.1.10 of ISO13666:2019(E), where focal power is the ability of an ophthalmic lens (3.5.2) or an optical surface to change the curvature or direction of an incident wavefront by refraction. The contribution of each inkjet-printed layer to the focal power of the ophthalmic lens depends on the number of layers required for the inkjet-printed ophthalmic lens. The number of layers in turn corresponds to the number of layers of the corresponding sliced ​​digital twin. Therefore, the contribution of each layer to the focal power of the ophthalmic lens is 1 / the number of layers. In contrast to each layer contributing to the focal power of the digital twin of the ophthalmic lens and correspondingly contributing to the focal power of the ophthalmic lens, the focal power of the ophthalmic lens disclosed in WO 2021 / 209551 A1 is achieved by the form of the front surface and the form of the back surface. This in turn means that in WO 2021 / 209551 A1 Figure 2 The unavoidable overheight of the printed layer shown in and disclosed in lines 26 to 28 on page 1 (overheight occurs at the edge of the printed layer due to the superposition of the surface tension of the printing ink and causes the shape of the printed structure to be different from the expected shape) has a greater impact on the focal length of the eyeglass of WO 2021 / 209551 A1 than on the focal length of the aforementioned digital twin or the corresponding aforementioned eyeglass. Therefore, the problem with WO 2021 / 209551 A1 is that, because the focal length of the eyeglass deviates from the expected focal length due to the overheight described in WO 2021 / 209551 A1, the overheight that always exists at the edge of the layer must be controlled and minimized, for example, by the blank space, while the aforementioned digital twin and the corresponding aforementioned eyeglass do not have the problem of WO 2021 / 209551 A1 to such an extent, because here each layer contributes to the focal length of the digital twin and the corresponding eyeglass.

[0107] "Locate a volume element" shall include locating a volume element at a discrete x, y, z position or locating multiple volume elements at multiple discrete x, y, z positions. Locating multiple volume elements shall include locating a volume element of the multiple volume elements at each discrete x, y, z position, i.e., as described above, a volume element is located at a corresponding discrete x, y, z position.

[0108] "No volume element is positioned" shall mean that no volume element is positioned at a discrete x, y, z position.

[0109] "Discrete" shall mean an integer multiple of the minimum nozzle distance of an inkjet print head or an arrangement of two or more inkjet print heads.

[0110] "Inkjet print head" shall mean a single inkjet print head or an arrangement of two or more inkjet print heads.

[0111] The “layer thickness” is preferably the following shortest point-to-point distance in the z-direction in a side view of the sliced ​​digital twin of the ophthalmic lens projected in the plane defined by the x-direction and the y-direction:

[0112] - the shortest distance between a point on the outermost surface of a layer and a point on the nearest interface of said layer that is perpendicular to said point in the z direction, or

[0113] - The shortest distance between a point on the interface of one layer with another layer and a point on the nearest interface of said layers which is perpendicular to said point in the z direction.

[0114] The above-mentioned problem is completely solved by a computer-implemented method as described above. Targeted positioning of volume elements in a layer, depending on or based on the positioning of volume elements in adjacent layers, results in a change in the density of volume elements in said layer. Said change in the density of volume elements results in a change in the layer thickness when an inkjet printer, preferably a print head of an inkjet printer, releases a jet to form ink drops at a position corresponding to said targeted positioned volume elements. Thus, in turn, the formation of steps in the inkjet-printed ophthalmic lens is avoided.

[0115] In a preferred embodiment of the present invention, the computer-implemented method is characterized by one of the following conditions:

[0116] -When the discrete x m ,y m ,z m ……x n ,y n ,z n If less than 50% of the positions have volume elements positioned, no volume elements are positioned at the discrete x m+1 ,y m+1 ,z m+1……x n+1 ,y n+1 ,z n+1 Each of the positions is positioned at a discrete x position in the layer stack. m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 Each of the positions;

[0117] -When the discrete x m ,y m ,z m ……x n ,y n ,z n When 50% or more of the positions have volume elements positioned, the volume elements are partially positioned at the following positions:

[0118] ○The discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 location, and

[0119] ○ The discrete x of each layer in the layer stack m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 Location;

[0120] The discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 The position and the discrete x of the layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Positioned directly adjacent to and on top of it.

[0121] When the discrete x m ,y m ,z m ……x n ,y n ,z n If 50% or more of the positions are located with volume elements, the volume elements are partially located at the discrete xm+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 position, and partially locates the volume element at every other discrete x in the layer stack m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 Location.

[0122] When the discrete x in the adjacent layer m ,y m ,z m ……x n ,y n ,z n If less than 50% of the positions have already been positioned with volume elements, no volume elements are positioned at the discrete x position of the layer. m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 position, but when the discrete x m ,y m ,z m ……x n ,y n ,z n If less than 50% of the positions have volume elements already located, the volume elements are located at discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 Position, which means that the volume element of the alternate layer is positioned on top of the volume element of the adjacent layer, but the two volume elements are not adjacent to each other. In the layer between the adjacent layer and the alternate layer, the volume element is positioned at a discrete x m+1a ,y m+1a ,z m+1a ……x n+1a ,y n+1a ,z n+1a position, so that it is not located at the discrete x positioned in the adjacent layer m ,y m ,z m ……x n ,y n ,z n Preferably, as mentioned above, when the discrete x m+1a ,ym+1a ,z m+1a ……x n+1a ,y n+1a ,z n+1a When positioning the volume, the maximum distance between two volume elements is taken into account. Preferably, as mentioned above, in the layer, the change of the distance between two adjacent volume elements is minimized.

[0123] When the discrete x in the adjacent layer m ,y m ,z m ……x n ,y n ,z n When 50% or more of the positions have already been positioned with volume elements, the volume elements are positioned at the discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Position or not position the volume element at discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 position, and when the discrete x in the adjacent layer m ,y m ,z m ……x n ,y n ,z n When 50% or more of the positions have been positioned with volume elements, the volume elements are positioned at the discrete x positions of the adjacent layers. m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 Position or not position the volume element at discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 position, which means that, preferably in a first step, when the discrete x m ,y m ,z m ……x n ,y n ,z n If a volume element is already located at the position, the volume element is not located at the discrete x of the layer. m+1 ,ym+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 position, and when the discrete x in the adjacent layer m ,y m ,z m ……x n ,y n ,z n If a volume element is already located at the position, the volume element is not located at the discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 location. Instead, the volume elements are positioned at discrete x m+1a ,y m+1a ,z m+1a ……x n+1a ,y n+1a ,z n+1a position, and thus the discrete x positioned in the adjacent layer m ,y m ,z m ……x n ,y n ,z n The volume element of the position is not adjacent to and is not located on top of it, and instead the volume element is located at the discrete x layer of the next layer m+2b ,y m+2b ,z m+2b ……x n+2b ,y n+2b ,z n+2b position, and thus the discrete x positioned at the layer m+1a ,y m+1a ,z m+1a ……x n+1a ,y n+1a ,z n+1a The volume element of the position is not adjacent to and is not located on top of it, and is not located in the discrete x located in the adjacent layer. m ,y m ,z m ……x n ,y n ,z n The top of the volume element at the position. m+1a ,y m+1a ,z m+1a ……x n+1a ,y n+1a ,z n+1a Location and all discrete x m+2b ,ym+2b ,z m+2b ……x n+2b ,y n+2b ,z n+2b If there are volume elements at all positions, then in the second step, the volume elements are located at the discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Location and Discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 Position. At all discrete x m+1a ,y m+1a ,z m+1a ……x n+1a ,y n+1a ,z n+1a Location and all discrete x m+2b ,y m+2b ,z m+2b ……x n+2b ,y n+2b ,z n+2b Before all volume elements are located, the volume elements can be located at discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Position and / or discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 Position. Preferably, when the discrete x m+1a ,y m+1a ,z m+1a ……x n+1a ,y n+1a ,z n+1a Location or discrete x m+2b ,y m+2b ,z m+2b ……x n+2b ,y n+2b ,z n+2bWhen positioning the volume, in each of the layer and the alternate layer, a maximum distance between two volume elements is considered. The maximum distance preferably corresponds to the maximum distance between two single ink droplets, which allows the two single ink droplets to coalesce in the inkjet-printed layer, thereby ensuring a continuous inkjet-printed layer. Preferably, when (i) at discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 location, (ii) in discrete x m+1a ,y m+1a ,z m+1a ……x n+1a ,y n+1a ,z n+1a location, (iii) in discrete x m+2b ,y m+2b ,z m+2b ……x n+2b ,y n+2b ,z n+2b position, or in discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 When positioning the volume elements, the variation of the distance between two adjacent volume elements in the layer or the alternate layer is minimized. The layered inkjet printing of the ophthalmic lens preferably enables the surface or interface of the layer or the alternate layer to be as smooth as possible while taking into account the minimized variation of the distance between two adjacent ink droplets in the layer.

[0124] In a preferred embodiment of the invention, the computer-implemented method is characterized by the following conditions:

[0125] -When the discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 50% or more of the position to the discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 When the volume element is positioned at 66% or less of the position, the volume element is positioned at the following positions:

[0126] ○Discrete x m+2b ,y m+2b ,zm+2b ……x n+2b ,y n+2b ,z n+2b position, thus the discrete x of the layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The volume element of the position is not adjacent to and is not located on top of it, and is not located in the discrete x of the adjacent layer m ,y m ,z m ……x n ,y n ,z n The top of the volume element of the location, or

[0127] ○Discrete x m+2a ,y m+2a ,z m+2a ……x n+2a ,y n+2a ,z n+2a position, thus the discrete x of the layer m+1a ,y m+1a ,z m+1a ……x n+1a ,y n+1a ,z n+1a The volume element of the position is adjacent to and located on top of it, and is not located in the discrete x of the adjacent layer m ,y m ,z m ……x n ,y n ,z n The top of the volume element of the location, or

[0128] ○Discrete x m+2b ,y m+2b ,z m+2b ……x n+2b ,y n+2b ,z n+2b position, thus the discrete x of the layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The volume element of the position is not adjacent to and is not located on top of it, and is located in the discrete x of the adjacent layer mb ,y mb ,z mb ……x nb ,y nb ,z nbThe top of the volume element of the location, or

[0129] ○Discrete x m+2a ,y m+2a ,z m+2a ……x n+2a ,y n+2a ,z n+2a position, thus the discrete x of the layer m+1a ,y m+1a ,z m+1a ……x n+1a ,y n+1a ,z n+1a The volume element of the position is adjacent to and located on top of it, and the discrete x ma ,y ma ,z ma ……x na ,y na ,z na The top of the volume element of the location.

[0130] Preferably, this condition takes into account the positioning of the volume element in said alternate layer. Preferably, for positioning the volume element in said layer, one of the above conditions shall apply.

[0131] Preferably, as mentioned above, when the discrete x of the layer m+1a ,y m+1a ,z m+1a ……x n+1a ,y n+1a ,z n+1a Position or discrete x in the interval m+2b ,y m+2b ,z m+2b ……x n+2b ,y n+2b ,z n+2b When positioning the volume, the maximum distance between two volume elements is considered. Preferably, as mentioned above, in each of the aforementioned layers, the variation of the distance between two adjacent volume elements is minimized.

[0132] Preferably, when the discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 50% or more of the position to the discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2If the volume element is located at 66% or less of the position, the volume element is located at the discrete x m+2b ,y m+2b ,z m+2b ……x n+2b ,y n+2b ,z n+2b position, thus the discrete x of the layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The volume element of the position is not adjacent to and is not located on top of it, and is not located in the discrete x of the adjacent layer m ,y m ,z m ……x n ,y n ,z n The top of the volume element of the location.

[0133] If we want to discrete x in the m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 50% or more of the position to the discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 66% or less of the position of the volume element, and

[0134] (i) In the layer or one of the adjacent layers, at discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Position or in discrete x m ,y m ,z m ……x n ,y n ,z n The location already has a volume element located, or

[0135] (ii) In the layer or in both the adjacent layers, at discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1The position and the discrete x m ,y m ,z m ……x n ,y n ,z n The position has been positioned with volume elements,

[0136] Then preferably, the corresponding aforementioned positioning should apply.

[0137] In a preferred embodiment of the invention, the computer-implemented method is characterized by the following conditions:

[0138] - When the discrete x of the layer adjacent to the layer is to be m+3 ,y m+3 ,z m+3 ……x n+3 ,y n+3 ,z n+3 greater than 66% of the locations to the discrete x m+3 ,y m+3 ,z m+3 ……x n+3 ,y n+3 ,z n+3 When the volume element is positioned at 75% or less than 75% of the position, the volume element is positioned at the following positions:

[0139] ○Discrete x m+3b ,y m+3b ,z m+3b ……x n+3b ,y n+3b ,z n+3b position, thus separating the discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 The volume element of the position is not adjacent to and is not located on top of it, and is not located in the discrete x of the layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The discrete x on top of the volume element of the position and not located in the adjacent layer m ,y m ,z m ……x n ,y n ,z n The top of the volume element of the location, or

[0140] ○Discrete x m+3b ,ym+3b ,z m+3b ……x n+3b ,y n+3b ,z n+3b position, thus separating the discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 The volume element of the position is not adjacent to and is not located on top of it, and is not located in the discrete x of the layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The volume element at the top of the position and the discrete x at the adjacent layer mb ,y mb ,z mb ……x nb ,y nb ,z nb The top of the volume element of the location, or

[0141] ○Discrete x m+3b ,y m+3b ,z m+3b ……x n+3b ,y n+3b ,z n+3b position, thus separating the discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 The volume element of the position is not adjacent to and is not located on top of it and is located at the discrete x of the layer m+1b ,y m+1b ,z m+1b ……x n+1b ,y n+1b ,z n+1b The discrete x on top of the volume element of the position and not located in the adjacent layer m ,y m ,z m ……x n ,y n ,z n The top of the volume element of the location, or

[0142] ○Discrete x m+3a ,y m+3a ,z m+3a ……x n+3a ,y n+3a ,zn+3a position, thus separating the discrete x m+2a ,y m+2a ,z m+2a ……x n+2a ,y n+2a ,z n+2a The volume element of the position is adjacent to and located on top of it and is not located in the discrete x layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The discrete x on top of the volume element of the position and not located in the adjacent layer m ,y m ,z m ……x n ,y n ,z n The top of the volume element of the location, or

[0143] ○Discrete x m+3a ,y m+3a ,z m+3a ……x n+3a ,y n+3a ,z n+3a position, thus separating the discrete x m+2a ,y m+2a ,z m+2a ……x n+2a ,y n+2a ,z n+2a The volume element of the position is adjacent to and located on top of it and is not located in the discrete x layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The volume element at the top of the position and the discrete x at the adjacent layer ma ,y ma ,z ma ……x na ,y na ,z na The top of the volume element of the location, or

[0144] ○Discrete x m+3a ,y m+3a ,z m+3a ……x n+3a ,y n+3a ,z n+3a position, thus separating the discrete x m+2a ,y m+2a ,zm+2a ……x n+2a ,y n+2a ,z n+2a The volume element of the position is adjacent to and located on top of it and is located at the discrete x m+1a ,y m+1a ,z m+1a ……x n+1a ,y n+1a ,z n+1a The discrete x on top of the volume element of the position and not located in the adjacent layer ma ,y ma ,z ma ……x na ,y na ,z na The top of the volume element of the location, or

[0145] ○Discrete x m+3b ,y m+3b ,z m+3b ……x n+3b ,y n+3b ,z n+3b position, thus separating the discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 The volume element of the position is not adjacent to and is not located on top of it and is located at the discrete x of the layer m+1b ,y m+1b ,z m+1b ……x n+1b ,y n+1b ,z n+1b The volume element at the top of the position and the discrete x at the adjacent layer mb ,y mb ,z mb ……x nb ,y nb ,z nb The top of the volume element of the location, or

[0146] ○Discrete x m+3a ,y m+3a ,z m+3a ……x n+3a ,y n+3a ,z n+3a position, thus separating the discrete x m+2a ,y m+2a ,z m+2a ……x n+2a ,y n+2a ,z n+2aThe volume element of the position is adjacent to and located on top of it and is located at the discrete x m+1a ,y m+1a ,z m+1a ……x n+1a ,y n+1a ,z n+1a The volume element at the top of the position and the discrete x at the adjacent layer ma ,y ma ,z ma ……x na ,y na ,z na The top of the volume element of the location.

[0147] Preferably, this condition takes into account the positioning of the volume element in the layer adjacent to the layer next to the next layer. An overview of the possible positioning of the volume element in three layers below the layer adjacent to the layer next to the next layer is given in Table 1, summarizing the foregoing. Preferably, the above conditions shall apply for positioning the volume element in the layer and the layer next to the next layer.

[0148] Preferably, as mentioned above, when the discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Position, in discrete x m+1a ,y m+1a ,z m+1a ……x n+1a ,y n+1a ,z n+1a Position, in discrete x m+1b ,y m+1b ,z m+1b ……x n+1b ,y n+1b ,z n+1b Position, in discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 Position, in discrete x m+2a ,y m+2a ,z m+2a ……x n+2a ,y n+2a ,z n+2a Position, in discrete x m+2b ,y m+2b ,z m+2b ……x n+2b ,y n+2b ,z n+2b Position, in discrete xm+3a ,y m+3a ,z m+3a ……x n+3a ,y n+3a ,z n+3a position, or in discrete x m+3b ,y m+3b ,z m+3b ……x n+3b ,y n+3b ,z n+3b When positioning the volume elements, in each of the layers, the maximum distance between two volume elements is considered. Preferably, as mentioned above, in each of the aforementioned layers, the variation of the distance between two adjacent volume elements is minimized.

[0149] Table 1: Possible positioning of volume elements below the layer adjacent to the next layer in the layer stack

[0150] One layer <![CDATA[x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 ]]> - - - + + + - + layer <![CDATA[x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 ]]> - - + - - + + + Adjacent layers <![CDATA[x m ,y m ,z m ……x n ,y n ,z n ]]> - + - - + - + +

[0151] - indicates positioning without volume elements, + indicates positioning with volume elements

[0152] Preferably, when the discrete x of the layer adjacent to the layer is to be m+3 ,y m+3 ,z m+3 ……x n+3 ,y n+3 ,z n+3 greater than 66% of the locations to the discrete x m+3 ,y m+3 ,z m+3 ……x n+3 ,y n+3 ,z n+3 When the volume element is positioned at 75% or less than 75% of the position, the volume element is positioned at the following position: Discrete x m+3b ,y m+3b ,z m+3b ……x n+3b ,y n+3b ,z n+3b position, thus separating the discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 The volume element of the position is not adjacent to and is not located on top of it, and is not located in the discrete x of the layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1The discrete x on top of the volume element of the position and not located in the adjacent layer m ,y m ,z m ……x n ,y n ,z n The top of the volume element of the location.

[0153] If we want to use the discrete x of the layer adjacent to the layer m+3 ,y m+3 ,z m+3 ……x n+3 ,y n+3 ,z n+3 greater than 66% of the locations to the discrete x m+3 ,y m+3 ,z m+3 ……x n+3 ,y n+3 ,z n+3 75% or less of the position locates the volume element, and

[0154] (i) In the alternate layer, the layer or one of the adjacent layers, at discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 Position, in discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Position or in discrete x m ,y m ,z m ……x n ,y n ,z n The location already has a volume element located, or

[0155] (ii) in the alternate layer, the layer or two of the adjacent layers, at discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 Position, in discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Position or in discrete x m ,ym ,z m ……x n ,y n ,z n The location already has a volume element located, or

[0156] (iii) In each of the alternate layer, the layer, and the adjacent layer, at discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 Position, in discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The position and the discrete x m ,y m ,z m ……x n ,y n ,z n The position has been positioned with volume elements,

[0157] Then preferably, the corresponding aforementioned positioning should apply.

[0158] In a preferred embodiment of the invention, the computer-implemented method is characterized by the following conditions:

[0159] - When the layer is to be separated from the adjacent layer by three layers, that is, the layer separated from the adjacent layer by the layer, the layer separated by one layer, and the layer adjacent to the layer separated by one layer, the discrete x m+4 ,y m+4 ,z m+4 ……x n+4 ,y n+4 ,z n+4 greater than 75% of the locations to the discrete x m+4 ,y m+4 ,z m+4 ……x n+4 ,y n+4 ,z n+4 When the volume element is positioned at less than 80% of the position, the volume element is positioned at the following positions:

[0160] ○Discrete x m+4b ,y m+4b ,z m+4b ……x n+4b ,y n+4b ,z n+4b position, thus the discrete x of the layer adjacent to the layer m+3 ,ym+3 ,z m+3 ……x n+3 ,y n+3 ,z n+3 The volume element of the position is not adjacent to and is not located on top of it, and is not located in the discrete x layer of the next layer m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 The discrete x of the volume element of the position and not located in the layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The discrete x on top of the volume element of the position and not located in the adjacent layer m ,y m ,z m ……x n ,y n ,z n The top of the volume element of the location, or

[0161] ○Discrete x m+4b ,y m+4b ,z m+4b ……x n+4b ,y n+4b ,z n+4b position, thus the discrete x of the layer adjacent to the layer m+3 ,y m+3 ,z m+3 ……x n+3 ,y n+3 ,z n+3 The volume element of the position is not adjacent to and is not located on top of it, and is not located in the discrete x layer of the next layer m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 The discrete x of the volume element of the position and not located in the layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The volume element at the top of the position and the discrete x at the adjacent layer m ,y m ,z m ……x n ,y n ,zn The top of the volume element of the location, or

[0162] ○Discrete x m+4b ,y m+4b ,z m+4b ……x n+4b ,y n+4b ,z n+4b position, thus the discrete x of the layer adjacent to the layer m+3 ,y m+3 ,z m+3 ……x n+3 ,y n+3 ,z n+3 The volume element of the position is not adjacent to and is not located on top of it, and is not located in the discrete x layer of the next layer m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 The volume element of the position is located on top of the discrete x m+1b ,y m+1b ,z m+1b ……x n+1b ,y n+1b ,z n+1b The discrete x on top of the volume element of the position and not located in the adjacent layer m ,y m ,z m ……x n ,y n ,z n The top of the volume element of the location, or

[0163] ○Discrete x m+4b ,y m+4b ,z m+4b ……x n+4b ,y n+4b ,z n+4b position, thus the discrete x of the layer adjacent to the layer m+3 ,y m+3 ,z m+3 ……x n+3 ,y n+3 ,z n+3 The volume element of the position is not adjacent to and is not located on top of it, and is located at the discrete x m+2b ,y m+2b ,z m+2b ……x n+2b ,y n+2b ,z n+2b The discrete x of the volume element of the position and not located in the layer m+1,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The discrete x on top of the volume element of the position and not located in the adjacent layer m ,y m ,z m ……x n ,y n ,z n The top of the volume element of the location, or

[0164] ○Discrete x m+4a ,y m+4a ,z m+4a ……x n+4a ,y n+4a ,z n+4a position, thus the discrete x of the layer adjacent to the layer m+3a ,y m+3a ,z m+3a ……x n+3a ,y n+3a ,z n+3a The volume element of the position is adjacent to and located on top of it, and is not located in the discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 The discrete x of the volume element of the position and not located in the layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The discrete x on top of the volume element of the position and not located in the adjacent layer m ,y m ,z m ……x n ,y n ,z n The top of the volume element of the location, or

[0165] ○Discrete x m+4b ,y m+4b ,z m+4b ……x n+4b ,y n+4b ,z n+4b position, thus the discrete x of the layer adjacent to the layer m+3 ,y m+3 ,z m+3 ……x n+3 ,yn+3 ,z n+3 The volume element of the position is not adjacent to and is not located on top of it, and is not located in the discrete x layer of the next layer m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 The volume element of the position is located on top of the discrete x m+1b ,y m+1b ,z m+1b ……x n+1b ,y n+1b ,z n+1b The volume element at the top of the position and the discrete x at the adjacent layer mb ,y mb ,z mb ……x nb ,y nb ,z nb The top of the volume element of the location, or

[0166] ○Discrete x m+4b ,y m+4b ,z m+4b ……x n+4b ,y n+4b ,z n+4b position, thus the discrete x of the layer adjacent to the layer m+3 ,y m+3 ,z m+3 ……x n+3 ,y n+3 ,z n+3 The volume element of the position is not adjacent to and is not located on top of it, and is located at the discrete x m+2b ,y m+2b ,z m+2b ……x n+2b ,y n+2b ,z n+2b The discrete x of the volume element of the position and not located in the layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The volume element at the top of the position and the discrete x at the adjacent layer mb ,y mb ,z mb ……x nb ,y nb ,z nb The top of the volume element of the location, or

[0167] ○Discrete x m+4b ,y m+4b ,z m+4b ……x n+4b ,y n+4b ,z n+4b position, thus the discrete x of the layer adjacent to the layer m+3 ,y m+3 ,z m+3 ……x n+3 ,y n+3 ,z n+3 The volume element of the position is not adjacent to and is not located on top of it, and is located at the discrete x m+2b ,y m+2b ,z m+2b ……x n+2b ,y n+2b ,z n+2b The volume element of the position is located on top of the discrete x m+1b ,y m+1b ,z m+1b ……x n+1b ,y n+1b ,z n+1b The discrete x on top of the volume element of the position and not located in the adjacent layer m ,y m ,z m ……x n ,y n ,z n The top of the volume element of the location, or

[0168] ○Discrete x m+4a ,y m+4a ,z m+4a ……x n+4a ,y n+4a ,z n+4a position, thus the discrete x of the layer adjacent to the layer m+3a ,y m+3a ,z m+3a ……x n+3a ,y n+3a ,z n+3a The volume element of the position is adjacent to and located on top of it, and is not located in the discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 The volume element of the position is located on top of the discrete x m+1a ,y m+1a ,z m+1a ……x n+1a ,yn+1a ,z n+1a The discrete x on top of the volume element of the position and not located in the adjacent layer m ,y m ,z m ……x n ,y n ,z n The top of the volume element of the location, or

[0169] ○Discrete x m+4a ,y m+4a ,z m+4a ……x n+4a ,y n+4a ,z n+4a position, thus the discrete x of the layer adjacent to the layer m+3a ,y m+3a ,z m+3a ……x n+3a ,y n+3a ,z n+3a The volume element of the position is adjacent to and located on top of it, and is located at the discrete x m+2a ,y m+2a ,z m+2a ……x n+2a ,y n+2a ,z n+2a The discrete x of the volume element of the position and not located in the layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The discrete x on top of the volume element of the position and not located in the adjacent layer m ,y m ,z m ……x n ,y n ,z n The top of the volume element of the location, or

[0170] ○Discrete x m+4a ,y m+4a ,z m+4a ……x n+4a ,y n+4a ,z n+4a position, thus the discrete x of the layer adjacent to the layer m+3a ,y m+3a ,z m+3a ……x n+3a ,y n+3a ,z n+3aThe volume element of the position is adjacent to and located on top of it, and is not located in the discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 The volume element of the position is located on top of the discrete x m+1a ,y m+1a ,z m+1a ……x n+1a ,y n+1a ,z n+1a The discrete x on top of the volume element of the position and not located in the adjacent layer m ,y m ,z m ……x n ,y n ,z n The top of the volume element of the location, or

[0171] ○Discrete x m+4b ,y m+4b ,z m+4b ……x n+4b ,y n+4b ,z n+4b position, thus the discrete x of the layer adjacent to the layer m+3 ,y m+3 ,z m+3 ……x n+3 ,y n+3 ,z n+3 The volume element of the position is not adjacent to and is not located on top of it, and is located at the discrete x m+2b ,y m+2b ,z m+2b ……x n+2b ,y n+2b ,z n+2b The volume element of the position is located on top of the discrete x m+1b ,y m+1b ,z m+1b ……x n+1b ,y n+1b ,z n+1b The volume element at the top of the position and the discrete x at the adjacent layer mb ,y mb ,z mb ……x nb ,y nb ,z nb The top of the volume element of the location, or

[0172] ○Discrete x m+4a ,ym+4a ,z m+4a ……x n+4a ,y n+4a ,z n+4a position, thus the discrete x of the layer adjacent to the layer m+3a ,y m+3a ,z m+3a ……x n+3a ,y n+3a ,z n+3a The volume element of the position is adjacent to and located on top of it, and is not located in the discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 The discrete x of the volume element of the position and not located in the layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The volume element at the top of the position and the discrete x at the adjacent layer ma ,y ma ,z ma ……x na ,y na ,z na The top of the volume element of the location, or

[0173] ○Discrete x m+4a ,y m+4a ,z m+4a ……x n+4a ,y n+4a ,z n+4a position, thus the discrete x of the layer adjacent to the layer m+3a ,y m+3a ,z m+3a ……x n+3a ,y n+3a ,z n+3a The volume element of the position is adjacent to and located on top of it, and is located at the discrete x m+2a ,y m+2a ,z m+2a ……x n+2a ,y n+2a ,z n+2a The discrete x of the volume element of the position and not located in the layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1The volume element at the top of the position and the discrete x at the adjacent layer ma ,y ma ,z ma ……x na ,y na ,z na The top of the volume element of the location, or

[0174] ○Discrete x m+4a ,y m+4a ,z m+4a ……x n+4a ,y n+4a ,z n+4a position, thus the discrete x of the layer adjacent to the layer m+3a ,y m+3a ,z m+3a ……x n+3a ,y n+3a ,z n+3a The volume element of the position is adjacent to and located on top of it, and is located at the discrete x m+2a ,y m+2a ,z m+2a ……x n+2a ,y n+2a ,z n+2a The volume element of the position is located on top of the discrete x m+1a ,y m+1a ,z m+1a ……x n+1a ,y n+1a ,z n+1a The discrete x on top of the volume element of the position and not located in the adjacent layer m ,y m ,z m ……x n ,y n ,z n The top of the volume element of the location, or

[0175] ○Discrete x m+4a ,y m+4a ,z m+4a ……x n+4a ,y n+4a ,z n+4a position, thus the discrete x of the layer adjacent to the layer m+3a ,y m+3a ,z m+3a ……x n+3a ,y n+3a ,z n+3a The volume element of the position is adjacent to and located on top of it, and is located at the discrete x m+2a ,y m+2a,z m+2a ……x n+2a ,y n+2a ,z n+2a The volume element of the position is located on top of the discrete x m+1a ,y m+1a ,z m+1a ……x n+1a ,y n+1a ,z n+1a The volume element at the top of the position and the discrete x at the adjacent layer ma ,y ma ,z ma ……x na ,y na ,z na The top of the volume element of the location.

[0176] Preferably, this condition allows for the positioning of a volume element in the layer which is three layers away from the adjacent layer. An overview of the possible positioning of a volume element in four layers below the layer adjacent to ...

[0177] Preferably, as mentioned before, when the discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Position, at x m+1a ,y m+1a ,z m+1a ……x n+1a ,y n+1a ,z n+1a Position, at x m+1b ,y m+1b ,z m+1b ……x n+1b ,y n+1b ,z n+1b Position, in discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 Position, in discrete x m+2a ,y m+2a ,z m+2a ……x n+2a ,y n+2a ,z n+2a Position, in discrete x m+2b ,y m+2b,z m+2b ……x n+2b ,y n+2b ,z n+2b Position, in discrete x m+3 ,y m+3 ,z m+3 ……x n+3 ,y n+3 ,z n+3 Position, in discrete x m+3a ,y m+3a ,z m+3a ……x n+3a ,y n+3a ,z n+3a Position, in discrete x m+3b ,y m+3b ,z m+3b ……x n+3b ,y n+3b ,z n+3b Position, in discrete x m+4a ,y m+4a ,z m+4a ……x n+4a ,y n+4a ,z n+4a position, or in discrete x m+4b ,y m+4b ,z m+4b ……x n+4b ,y n+4b ,z n+4b When positioning the volume, in each of these layers, the maximum distance between two volume elements is considered. Preferably, as mentioned above, in each of the aforementioned layers, the variation of the distance between two adjacent volume elements is minimized.

[0178] Table 2: Possible positioning of volume elements below a layer in a layer stack that is three layers away from an adjacent layer

[0179]

[0180] - indicates positioning without volume elements, + indicates positioning with volume elements

[0181] Continuation of Table 2:

[0182]

[0183]

[0184] - indicates positioning without volume elements, + indicates positioning with volume elements

[0185] Preferably, when the discrete x of a layer is to be spaced three layers apart from the adjacent layer m+4 ,y m+4 ,zm+4 ……x n+4 ,y n+4 ,z n+4 greater than 75% of the locations to the discrete x m+4 ,y m+4 ,z m+4 ……x n+4 ,y n+4 ,z n+4 When less than 80% of the positions are used to locate the volume element, the volume element is located at the discrete x m+4b ,y m+4b ,z m+4b ……x n+4b ,y n+4b ,z n+4b position, thus the discrete x of the layer adjacent to the layer m+3 ,y m+3 ,z m+3 ……x n+3 ,y n+3 ,z n+3 The volume element of the position is not adjacent to and is not located on top of it, and is not located in the discrete x layer of the next layer m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 The discrete x of the volume element of the position and not located in the layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The discrete x on top of the volume element of the position and not located in the adjacent layer m ,y m ,z m ……x n ,y n ,z n The top of the volume element of the location.

[0186] If, when the discrete x of a layer is to be separated from the adjacent layer by three layers m+4 ,y m+4 ,z m+4 ……x n+4 ,y n+4 ,z n+4 greater than 75% of the locations to the discrete x m+4 ,y m+4 ,z m+4 ……x n+4 ,y n+4 ,z n+4less than 80% of the positions of the volume element are located, and (i) in one of the layers adjacent to the layer next to the layer next to the layer next to the layer, the layer next to the layer, the layer or the adjacent layer, in the discrete x m+3 ,y m+3 ,z m+3 ……x n+3 ,y n+3 ,z n+3 Position, in discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 Position, in discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Position or in discrete x m ,y m ,z m ……x n ,y n ,z n The location already has a volume element located, or

[0187] (ii) in the layer adjacent to the layer next to the layer next to the layer next to the layer next to the layer, the layer next to the layer, or two of the adjacent layers, at discrete x m+3 ,y m+3 ,z m+3 ……x n+3 ,y n+3 ,z n+3 Position, in discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 Position, in discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Position or in discrete x m ,y m ,z m ……x n ,y n ,z n The location already has a volume element located, or

[0188] (iii) in the layer adjacent to the layer next to the layer next to the layer next to the layer, the layer next to the layer, the layer or the three adjacent layers, in the discrete x m+3 ,ym+3 ,z m+3 ……x n+3 ,y n+3 ,z n+3 Position, in discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 Position, in discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Position or in discrete x m ,y m ,z m ……x n ,y n ,z n The location already has a volume element located, or

[0189] (iv) in each of the layer adjacent to the layer next to the layer next to the layer next to the layer, the layer next to the layer, the layer or the adjacent layer, at discrete x m+3 ,y m+3 ,z m+3 ……x n+3 ,y n+3 ,z n+3 Position, in discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 Position, in discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Position or in discrete x m ,y m ,z m ……x n ,y n ,z n The position has been located with volume elements

[0190] Then preferably, the corresponding aforementioned positioning should apply.

[0191] In a preferred embodiment of the invention, the computer-implemented method is characterized by the following additional steps:

[0192] (iii) Determine the discrete x of the adjacent layer m ,ym ,z m ……x n ,y n ,z n The actual value of the layer thickness at a position is the same as the discrete value of the adjacent layer x m ,y m ,z m ……x n ,y n ,z n The deviation of the layer thickness at a location from the default nominal value.

[0193] As described above, slicing the digital twin of the eyeglass lens into a layer stack determines the layer thickness of each layer in the layer stack at each discrete x, y, z position. The layer thickness is preset. The layer thickness has a default nominal value at each discrete x, y, z position.

[0194] As further described above, each layer in the layer stack is converted into a spatial volume element pattern in which a volume element or no volume element is positioned at a discrete x, y, z position. The volume element can be represented, for example, as a cuboid with a preset edge length, preferably, the volume element is represented as a cube with a preset edge length. Preferably, when the layer stack is projected in a plane determined by the x-direction and the y-direction, and when each layer in the layer stack is viewed as a spatial volume element pattern, for example in a side view, at each discrete x, y, z position, the actual value of the layer thickness is determined. Positioning one or more volume elements at discrete x, y, z positions of the layer (as previously described, there is one volume element at each discrete x, y, z position when the layer is viewed in a side view) causes the actual value of the layer thickness at the discrete x, y, z position.

[0195] - is greater than the default nominal value of the layer thickness at the same discrete x, y, z position of the layer, or

[0196] - is less than the default nominal value of the layer thickness at the same discrete x, y, z position of the layer, or

[0197] - a default nominal value equal to the layer thickness at the same discrete x, y, z position of the layer.

[0198] The deviation of the actual value from the default nominal value is the difference between these two values.

[0199] In a preferred embodiment of the invention, the computer-implemented method is characterized by the following additional steps:

[0200] (iv) determining the sum of the deviation and the actual value of the layer thickness.

[0201] The determination of the sum is used as the discrete x at the layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The position is used to determine whether to position the volume element to be aligned with the discrete x of the adjacent layer. m ,y m ,z m ……x n ,y n ,z n The volume element of the position is adjacent to and located on top of it.

[0202] The computer-implemented method is configured for calculating a digital twin of an ophthalmic lens for use in the manufacture of the ophthalmic lens, the digital twin comprising a layer stack, the method being characterized by the following steps:

[0203] - determining the sum of the deviation of the layer thickness and the actual value of the layer thickness,

[0204] The deviation is the discrete x of adjacent layers. m ,y m ,z m ……x n ,y n ,z n The actual value of the layer thickness at a position is the same as the discrete value of the adjacent layer x m ,y m ,z m ……x n ,y n ,z n The deviation of the layer thickness at a location from the default nominal value.

[0205] Likewise, the computer-implemented method is suitable for generating printing instructions for inkjet printing of an ophthalmic lens. The computer-implemented method is suitable for generating printing instructions for inkjet printing of an ophthalmic lens.

[0206] WO 2021 / 209551 A1 describes, for example, on page 8, lines 8 to 18, that in order to match the calculated layer thickness (i.e., the nominal thickness), during printing, the layer deposition printing ink is controlled and possible deviations of the layer thickness are compensated. WO 2021 / 209551 A1 discloses on page 6, lines 11 to 13 that the deviations are determined by confocal scanning, and further discloses on page 6, lines 30 to 33 that the deviations of all layers to be printed are determined before printing using simulations. Therefore, WO 2021 / 209551 A1 uses control of the layer thickness during printing to match the nominal layer thickness of the printed layer, or uses simulations to match the nominal layer thickness of the layer to be printed. WO 2021 / 209551 A1 does not disclose the decision to position a volume element or (when printing) position a droplet directly adjacent to and on top of the x, y, z position based on the sum of the deviation of the layer thickness at the same x, y, z position and the actual value of the layer thickness.

[0207] In a preferred embodiment of the present invention, the computer-implemented method is further characterized by one of the following conditions:

[0208] -When the discrete x m ,y m ,z m ……x n ,y n ,z n If less than 50% of the positions have volume elements positioned, no volume elements are positioned at the discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Each of the positions;

[0209] -When the discrete x m ,y m ,z m ……x n ,y n ,z n If 50% or more of the positions are located with volume elements, the volume elements are partially located at the discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Location.

[0210] Refer to the explanation provided above.

[0211] In a preferred embodiment of the present invention, the computer-implemented method is further characterized by one of the following conditions:

[0212] -When the discrete x m ,y m ,z m ……x n ,y n ,z n If less than 50% of the positions have volume elements positioned, no volume elements are positioned at the discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Each of the positions is positioned at a discrete x position in the layer stack. m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 Each of the positions;

[0213] -When the discrete x m ,y m ,z m ……x n ,y n ,z n When 50% or more of the positions have volume elements positioned, the volume elements are partially positioned at the following positions:

[0214] ○The discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 location, and

[0215] ○ The discrete x of each layer in the layer stack m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 Location;

[0216] The discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 The position and the discrete x of the layer m+1 ,y m+1 ,zm+1 ……x n+1 ,y n+1 ,z n+1 Positioned directly adjacent to and on top of it.

[0217] Refer to the description given above.

[0218] In a preferred embodiment of the invention, the computer implemented method is further characterized in that the following conditions apply:

[0219] -When the discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 50% or more of the position to the discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 When the volume element is positioned at 66% or less of the position, the volume element is positioned at the following positions:

[0220] a. Discrete x m+2b ,y m+2b ,z m+2b ……x n+2b ,y n+2b ,z n+2b position, thus the discrete x of the layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The volume element of the position is not adjacent to and is not located on top of it, and is not located in the discrete x of the adjacent layer m ,y m ,z m ……x n ,y n ,z n The top of the volume element of the location, or

[0221] b. Discrete x m+2a ,y m+2a ,z m+2a ……x n+2a ,y n+2a ,z n+2a position, thus the discrete x of the layer m+1a ,y m+1a ,z m+1a ……x n+1a ,yn+1a ,z n+1a The volume element of the position is adjacent to and located on top of it, and is not located in the discrete x of the adjacent layer m ,y m ,z m ……x n ,y n ,z n The top of the volume element of the location, or

[0222] c. Discrete x m+2b ,y m+2b ,z m+2b ……x n+2b ,y n+2b ,z n+2b position, thus the discrete x of the layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The volume element of the position is not adjacent to and is not located on top of it, and is located in the discrete x of the adjacent layer mb ,y mb ,z mb ……x nb ,y nb ,z nb The top of the volume element of the location, or

[0223] d. Discrete x m+2a ,y m+2a ,z m+2a ……x n+2a ,y n+2a ,z n+2a position, thus the discrete x of the layer m+1a ,y m+1a ,z m+1a ……x n+1a ,y n+1a ,z n+1a The volume element of the position is adjacent to and located on top of it, and the discrete x ma ,y ma ,z ma ……x na ,y na ,z na The top of the volume element of the location.

[0224] Refer to the information provided above.

[0225] In a preferred embodiment of the invention, the computer implemented method is further characterized in that the following conditions apply:

[0226] - When the discrete x of the layer adjacent to the layer is to be m+3 ,y m+3 ,z m+3 ……x n+3 ,y n+3 ,z n+3 greater than 66% of the locations to the discrete x m+3 ,y m+3 ,z m+3 ……x n+3 ,y n+3 ,z n+3 When the volume element is positioned at 75% or less than 75% of the position, the volume element is positioned at the following positions:

[0227] a. Discrete x m+3b ,y m+3b ,z m+3b ……x n+3b ,y n+3b ,z n+3b position, thus separating the discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 The volume element of the position is not adjacent to and is not located on top of it, and is not located in the discrete x of the layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The discrete x on top of the volume element of the position and not located in the adjacent layer m ,y m ,z m ……x n ,y n ,z n The top of the volume element of the location, or

[0228] b. Discrete x m+3b ,y m+3b ,z m+3b ……x n+3b ,y n+3b ,z n+3b position, thus separating the discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 The volume element of the position is not adjacent to and is not located on top of it, and is not located in the discrete x of the layer m+1 ,y m+1,z m+1 ……x n+1 ,y n+1 ,z n+1 The volume element at the top of the position and the discrete x at the adjacent layer mb ,y mb ,z mb ……x nb ,y nb ,z nb The top of the volume element of the location, or

[0229] c. Discrete x m+3b ,y m+3b ,z m+3b ……x n+3b ,y n+3b ,z n+3b position, thus separating the discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 The volume element of the position is not adjacent to and is not located on top of it and is located at the discrete x of the layer m+1b ,y m+1b ,z m+1b ……x n+1b ,y n+1b ,z n+1b The discrete x on top of the volume element of the position and not located in the adjacent layer m ,y m ,z m ……x n ,y n ,z n The top of the volume element of the location, or

[0230] d. Discrete x m+3a ,y m+3a ,z m+3a ……x n+3a ,y n+3a ,z n+3a position, thus separating the discrete x m+2a ,y m+2a ,z m+2a ……x n+2a ,y n+2a ,z n+2a The volume element of the position is adjacent to and located on top of it and is not located in the discrete x layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1The discrete x on top of the volume element of the position and not located in the adjacent layer m ,y m ,z m ……x n ,y n ,z n The top of the volume element of the location, or

[0231] e. Discrete x m+3a ,y m+3a ,z m+3a ……x n+3a ,y n+3a ,z n+3a position, thus separating the discrete x m+2a ,y m+2a ,z m+2a ……x n+2a ,y n+2a ,z n+2a The volume element of the position is adjacent to and located on top of it and is not located in the discrete x layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The volume element at the top of the position and the discrete x at the adjacent layer ma ,y ma ,z ma ……x na ,y na ,z na The top of the volume element of the location, or

[0232] f. Discrete x m+3a ,y m+3a ,z m+3a ……x n+3a ,y n+3a ,z n+3a position, thus separating the discrete x m+2a ,y m+2a ,z m+2a ……x n+2a ,y n+2a ,z n+2a The volume element of the position is adjacent to and located on top of it and is located at the discrete x m+1a ,y m+1a ,z m+1a ……x n+1a ,y n+1a ,z n+1a The discrete x on top of the volume element of the position and not located in the adjacent layer ma ,y ma ,zma ……x na ,y na ,z na The top of the volume element of the location, or

[0233] g. Discrete x m+3b ,y m+3b ,z m+3b ……x n+3b ,y n+3b ,z n+3b position, thus separating the discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 The volume element of the position is not adjacent to and is not located on top of it and is located at the discrete x of the layer m+1b ,y m+1b ,z m+1b ……x n+1b ,y n+1b ,z n+1b The volume element at the top of the position and the discrete x at the adjacent layer mb ,y mb ,z mb ……x nb ,y nb ,z nb The top of the volume element of the location, or

[0234] h. Discrete x m+3a ,y m+3a ,z m+3a ……x n+3a ,y n+3a ,z n+3a position, thus separating the discrete x m+2a ,y m+2a ,z m+2a ……x n+2a ,y n+2a ,z n+2a The volume element of the position is adjacent to and located on top of it and is located at the discrete x m+1a ,y m+1a ,z m+1a ……x n+1a ,y n+1a ,z n+1a The volume element at the top of the position and the discrete x at the adjacent layer ma ,y ma ,z ma ……x na ,y na ,z naThe top of the volume element of the location.

[0235] Refer to the previous text for further information.

[0236] In a preferred embodiment of the invention, the computer implemented method is further characterized in that the following conditions apply:

[0237] - When the layer is to be separated from the adjacent layer by three layers, that is, the layer separated from the adjacent layer by the layer, the layer separated by one layer, and the layer adjacent to the layer separated by one layer, the discrete x m+4 ,y m+4 ,z m+4 ……x n+4 ,y n+4 ,z n+4 greater than 75% of the locations to the discrete x m+4 ,y m+4 ,z m+4 ……x n+4 ,y n+4 ,z n+4 When less than 80% of the positions position the volume element, the volume element is positioned as described above.

[0238] Reference is made to the further information given above in this context.

[0239] In a preferred embodiment of the present invention, the computer-implemented method is further characterized by one of the following conditions:

[0240] - when the sum is greater than half the default nominal value of the layer thickness, then no volume element is positioned at the discrete x value of the layer in the layer stack. m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Location;

[0241] - when the sum is less than or equal to half the default nominal value of the layer thickness, then locating a volume element at a discrete x value of the layer in the layer stack m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Location.

[0242] As mentioned before, the discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1The corresponding discrete x of the position and adjacent layer m ,y m ,z m ...x,y,z positions are directly adjacent to and on top of each other.

[0243] Since the volume element can be represented as a cuboid with a preset edge length, preferably as a cube with a preset edge length, and the layer thickness at each discrete x,y position of each layer is preset by slicing the digital twin of the eyeglass lens into a layer stack, then:

[0244] (i) positioning one or more volume elements at (one or more) said discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Location, or

[0245] (ii) not locating one or more volume elements within (one or more) said discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Location,

[0246] According to the conditions, the discrete x of the adjacent layers is corrected. m ,y m ,z m ……x n ,y n ,z n The actual value of the layer thickness at a position is the same as the discrete value of the adjacent layer x m ,y m ,z m ……x n ,y n ,z n The correction for said deviation may be:

[0247] - correcting said actual value to correspond to said default nominal value, or

[0248] - undercorrecting said actual value so as not to correspond to said default nominal value, or

[0249] - Overcorrecting the actual value so as not to correspond to the default nominal value.

[0250] Preferably, said correction of said deviation corrects said actual value to correspond to said default nominal value.

[0251] If the correction of the deviation would result in an undercorrection or overcorrection of the actual value, the undercorrection or overcorrection is distributed equally. The reason for the preferred equal distribution is that when printing an ophthalmic lens in layers, the total volume of ink drops to be positioned in a layer is equal to the volume of the layer.

[0252] When (i) locating a volume element or multiple volume elements or (ii) not locating a volume element or multiple volume elements according to the condition, the following items are considered:

[0253] - the maximum distance between two adjacent volume elements in the layer, or

[0254] - the maximum distance between two adjacent volume element stacks in the layer, or

[0255] - The maximum distance between a volume element in the layer and a stack of adjacent volume elements.

[0256] The maximum distance is preferably a distance corresponding to a distance that allows ink droplets to coalesce. The ink drops that are inkjet printed a) as two adjacent ink drops or b) as two adjacent ink drop stacks or c) as ink drops adjacent to an ink drop stack preferably form a continuous layer after coalescence.

[0257] Further, when (i) locating one or more volume elements or (ii) not locating one or more volume elements according to the condition, the following items are preferably minimized:

[0258] - the change in the distance between two adjacent volume elements in the layer, or

[0259] - a change in the distance between two adjacent volume element stacks in the layer, or

[0260] - A change in the distance between a volume element in the layer and a stack of adjacent volume elements.

[0261] When inkjet printing an ophthalmic lens in layers taking into account said minimization of variation of the following distances:

[0262] - the distance between two adjacent ink droplets in a layer, or

[0263] - the distance between two adjacent droplet stacks in a layer, or

[0264] - The distance between the ink droplets in a layer and the adjacent ink droplet stack

[0265] It is preferable to make the surface of the layer as smooth as possible.

[0266] In a preferred embodiment of the present invention, the computer-implemented method is further characterized by one of the following additional steps:

[0267] - determining said discrete x of said slice after said positioning of the volume elements m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The deviation of the layer thickness at the position is calculated from the default nominal value and the deviation is distributed to the adjacent discrete x values ​​in the same layer. o+1 ,y o+1 ,z o+1 ……x p+1 ,y p+1 ,z p+1 Location;

[0268] - determining said discrete x of said slice after said positioning of the volume elements m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The deviation of the layer thickness at position 1 from the default nominal value and transfers the deviation to the discrete x value of the layer at that interval m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 Location;

[0269] - determining said discrete x of said slice after said unpositioning of volume elements m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The deviation of the layer thickness at the position is calculated from the default nominal value and the deviation is distributed to the adjacent discrete x values ​​in the same layer. o+1 ,y o+1 ,z o+1 ……x p+1 ,y p+1 ,z p+1 Location;

[0270] - determining said discrete x of said slice after said unpositioning of volume elements m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1The deviation of the layer thickness at position 1 from the default nominal value and transfers the deviation to the discrete x value of the layer at that interval m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 Location.

[0271] Discrete x o+1 ,y o+1 ,z o+1 ……x p+1 ,y p+1 ,z p+1 Position and discrete x in the same layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The positions are adjacent. The discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 Discrete x of position and layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Positioned directly adjacent to and on top of it.

[0272] If the layer is the final layer in the layer stack, the transfer of the deviation can only take place within the final layer.

[0273] As previously described, the volume elements may be represented as cuboids with preset edge lengths, preferably as cubes with preset edge lengths, and the layer thickness at each discrete x, y, z position of each layer is preset by slicing the digital twin of the lens into a layer stack.

[0274] After:

[0275] (i) Positioning one or more volume elements at (one or more) discrete x of the layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Location, or

[0276] (ii) not locating one or more volume elements at the discrete x(s) of the layer m+1 ,ym+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Location,

[0277] Determine the discrete x of the layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The actual value of the layer thickness at the position and compare it with the discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The deviation from the default nominal value is compared to the default nominal value of the layer thickness at the position.

[0278] - distributed to adjacent discrete x in the same layer o+1 ,y o+1 ,z o+1 ……x p+1 ,y p+1 ,z p+1 Location, and

[0279] -Transfer to the next discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 Location.

[0280] Distribute the deviation to a neighboring discrete x o+1 ,y o+1 ,z o+1 ……x p+1 ,y p+1 ,z p+1 Position or multiple adjacent x o1+1 ,y o1+1 ,z o1+1 ……x p1+1 ,y p1+1 ,z p1+1 The position shall mean that when determining the discrete x o+1 ,y o+1 ,z o+1 ……x p+1 ,y p+1 ,z p+1 The position or the discrete x o1+1 ,y o1+1 ,z o1+1 ……xp1+1 ,y p1+1 ,z p1+1 The actual layer thickness at the position is taken into account. If the discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The actual value of the layer thickness at a position is less than the discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The default nominal value of the layer thickness at a position is taken into account as follows, for example, at adjacent discrete x o+1 ,y o+1 ,z o+1 ……x p+1 ,y p+1 ,z p+1 position, adding the difference in layer thickness to the adjacent discrete x o+1 ,y o+1 ,z o+1 ……x p+1 ,y p+1 ,z p+1 The actual layer thickness at the position. If the discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The actual value of the layer thickness at a position is greater than the discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The default nominal value of the layer thickness at a position is taken into account as follows, for example, at adjacent discrete x o+1 ,y o+1 ,z o+1 ……x p+1 ,y p+1 ,z p+1 position, the difference in layer thickness from the adjacent discrete x o+1 ,y o+1 ,z o+1 ……x p+1 ,y p+1 ,z p+1 The actual layer thickness at the position is subtracted. If the discrete x m+1 ,ym+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The actual value of the layer thickness at position is equal to the discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The default nominal value of the layer thickness at the position does not need to be transferred.

[0281] After the aforementioned distribution of the deviations, the computer-implemented method uses the adjacent discrete x o+1 ,y o+1 ,z o+1 ……x p+1 ,y p+1 ,z p+1 The position continues and applies the steps therein, i.e., determining the discrete x of the layer o+1 ,y o+1 ,z o+1 ……x p+1 ,y p+1 ,z p+1 The actual value of the layer thickness at the position and compare it with the discrete x o+1 ,y o+1 ,z o+1 ……x p+1 ,y p+1 ,z p+1 The deviation from the default nominal value is compared to the default nominal value of the layer thickness at the position.

[0282] - distributed to adjacent discrete x in the same layer q+1 ,y q+1 ,z q+1 ……x r+1 ,y r+1 ,z r+1 Location, and

[0283] -Transfer to the next discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 Location.

[0284] The determination is continued until for each discrete x of the layer m+1 ,y m+1 ,z m+1 ……x n+1 ,yn+1 ,z n+1 The position determines the deviation of the actual value of the layer thickness from the default nominal value of the layer thickness.

[0285] The sum of said deviations and the considered deviations distributed in the layer is preferably zero, in order to ensure that in the inkjet-printed lens the total ink drop volume is equivalent to the volume of the layer to be inkjet-printed.

[0286] Transfer the deviation to the next discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 Position shall mean that the deviation is taken into account in the said interval layer so that the volume element is preferably positioned at the discrete x in the said interval layer. m+2b ,y m+2b ,z m+2b ……x n+2b ,y n+2b ,z n+2b position, so that the discrete x is not located in the layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Therefore, when the layered inkjet printed eyeglasses are placed on the top of the volume element at the discrete x m+2b ,y m+2b ,z m+2b ……x n+2b ,y n+2b ,z n+2b When the ink drop is positioned by the positioning of the position, the transfer contributes to achieving (i) the interface of the ophthalmic lens or (ii) the surface of the ophthalmic lens as smooth as possible.

[0287] The computer-implemented method is configured for calculating a digital twin of an ophthalmic lens for use in manufacturing the ophthalmic lens, the digital twin having a front surface and a back surface, the method being characterized by the following steps:

[0288] - Calculate each discrete z of the front surface 前 (x,y) position and the corresponding discrete z of the back surface 后 The total number of volume elements between (x,y) positions, which calculates the volume element density distribution of the digital twin.

[0289] In the digital twin of the eyeglass lens, the distance from each discrete z (x, y) position of the front surface to the corresponding z (x, y) position of the back surface is preferably preset. For the corresponding distance between the front surface and the back surface at each discrete z (x, y) position, the two discrete z (x, y) positions of the front surface and the back surface differ only in their corresponding z positions. In other words, the distance between the discrete z (x, y) position of the front surface and the corresponding z (x, y) position of the back surface is the distance between positions having the same discrete x and y positions on the corresponding surfaces but having different z positions on the corresponding surfaces. The total number of volume elements for each corresponding distance between the front surface and the back surface of the digital twin can be calculated by dividing the lens thickness at the (x, y) position by the corresponding thickness of the fully printed layer. Preferably, with respect to the following items:

[0290] - said predetermined distance between the front surface and the back surface at each discrete z (x, y) position, i.e., z 后 (x,y) minus z 前 The absolute value of (x,y),

[0291] - the volume of a volume element,

[0292] the area of ​​said one volume element usually depends on the printing resolution of the inkjet printer, preferably the print head of said inkjet printer,

[0293] The total number of volume elements is calculated as the product of the predetermined distance and the area of ​​the one volume element divided by the volume of the one volume element:

[0294]

[0295] Calculating the total number of volume elements for each distance between the front surface and the back surface of the digital twin will result in a volume element density distribution of the digital twin. The volume element density distribution is a basis suitable for slicing the digital twin.

[0296] The computer-implemented method is suitable for generating printing instructions for inkjet printing of an ophthalmic lens. The computer-implemented method is suitable for generating printing instructions for inkjet printing of an ophthalmic lens.

[0297] Preferably, the method is configured for calculating a digital twin of an ophthalmic lens for use in the manufacture of the ophthalmic lens, the digital twin having a front surface and a back surface, the method being characterized by the following steps:

[0298] - determining a minimum number of layers to be comprised by the layer stack based on a calculated maximum total number of volume elements between discrete x, y, z positions of the front surface and corresponding discrete x, y, z positions of the back surface.

[0299] Preferably, the digital twin is sliced ​​such that the minimum number of layers at the maximum distance between the front surface and the back surface is determined. Assuming that the volume elements have the same volume and the same area, the maximum distance between the front surface and the back surface of the digital twin corresponds to the calculated maximum total number of volume elements.

[0300] Preferably, the method is configured for calculating a digital twin of an ophthalmic lens for use in the manufacture of the ophthalmic lens, the digital twin having a front surface and a back surface, the method being characterized by the following steps:

[0301] - uniformly distribute the volume elements in the following directions based on the calculated total number of volume elements:

[0302] ○ The z direction for each corresponding x,y,z position, and

[0303] o The x,y directions of each layer in the layer stack.

[0304] Uniformly distributing the volume elements with knowledge of the calculated total number of volume elements and the minimum number of layers of the layer stack preferably comprises: in the z direction between two corresponding x,y,z positions on the front surface and the back surface, when the total number of volume elements is less than the minimum number of layers, not distributing the total number of volume elements in subsequent layers in the layer stack, but distributing the total number of volume elements throughout the minimum number of layers. The resulting spatial volume pattern is then used as a basis for inkjet printing the ophthalmic lens.

[0305] Preferably, the method is configured for calculating a digital twin of an eyeglass lens for use in the manufacture of the eyeglass lens, the digital twin having a front surface and a rear surface, the method being characterized in that each layer in the layer stack has the same spatial extension when projected in a plane determined by the x-direction and the y-direction.

[0306] Preferably, the same spatial extension of all layers of the layers of the digital twin has the decisive advantage that in the case of an inkjet-printed spectacle lens (preferably an inkjet-printed spectacle lens according to a spatial volume element pattern resulting from either of the aforementioned volume element positioning or non-positioning), the inherent superelevation described in WO 2021 / 209551 A1, for example, on page 1, lines 25 to 28, is transferred to the edge of the printed spectacle lens. If necessary, such an edge with superelevation superimposed can be directly truncated.

[0307] The computer-implemented method described above is further configured to manufacture an ophthalmic lens based on a digital twin of the ophthalmic lens.

[0308] The computer according to the present invention is configured to perform the following steps:

[0309] -Determine the volume element positioning in the layers of the layer stack of the digital twin:

[0310] (i) Based on the discrete x of the adjacent layers in the layer stack of volume elements m ,y m ,z m ……x n ,y n ,z n Positioning, positioning the volume element at the discrete x of the layer in the layer stack m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Location, or

[0311] (ii) Based on the discrete x of the adjacent layers in the layer stack of volume elements m ,y m ,z m ……x n ,y n ,z n Positioning, not positioning the volume element at the discrete x of the layer in the layer stack m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Location,

[0312] The discrete x of the layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The position and the discrete x of the adjacent layer m ,y m ,z m ……x n ,y n ,z n Located directly adjacent to and on top of it,

[0313] Subject to the following conditions:

[0314] When the discrete x m ,y m ,z m ……x n ,y n ,z n If 50% or less of the positions have volume elements positioned, no volume elements are positioned at the discrete x position of the layer. m+1 ,ym+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Location;

[0315] When the discrete x m ,y m ,z m ……x n ,y n ,z n If more than 50% of the positions are located with volume elements, then the volume elements are partially located at the discrete x of the layer. m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Location,

[0316] And the inkjet printer prints the eyeglass lens according to the conditions.

[0317] The data processing system according to the present invention comprises a processor and a storage medium coupled to the processor, wherein the processor is adapted to perform the following steps:

[0318] (i) Discrete x based on volume elements of adjacent layers in the layer stack m ,y m ,z m ……x n ,y n ,z n Positioning, positioning the volume element at the discrete x of the layer in the layer stack m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Location, or

[0319] (ii) Discrete x based on the volume elements of adjacent layers in the layer stack m ,y m ,z m ……x n ,y n ,z n Positioning, not positioning the volume element at the discrete x of the layer in the layer stack m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Location,

[0320] The data processing system is configured for its use for layered inkjet printing of ophthalmic lenses.

[0321] The processor adapted to perform the above steps may be based on a computer program stored on a storage medium. The storage medium may be a non-transitory tangible computer-readable storage medium.

[0322] In a preferred embodiment, the data processing system includes a processor and a storage medium coupled to the processor, adapted to perform the steps according to one of the following conditions:

[0323] -When the discrete x m ,y m ,z m ……x n ,y n ,z n If less than 50% of the positions have volume elements positioned, no volume elements are positioned at the discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Each of the positions;

[0324] -When the discrete x m ,y m ,z m ……x n ,y n ,z n If 50% or more of the positions are located with volume elements, the volume elements are partially located at the discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Location.

[0325] In a preferred embodiment, the data processing system includes a processor and a storage medium coupled to the processor, adapted to perform the steps according to one of the following conditions:

[0326] -When the discrete x m ,y m ,z m ……x n ,y n ,z n If less than 50% of the positions have volume elements positioned, no volume elements are positioned at the discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,yn+1 ,z n+1 Each of the positions is positioned at a discrete x position in the layer stack. m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 Each of the positions;

[0327] -When the discrete x m ,y m ,z m ……x n ,y n ,z n If 50% or more of the positions are located with volume elements, the volume elements are partially located at the discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 position, and partially locates the volume element at every other discrete x in the layer stack m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 Location.

[0328] In a preferred embodiment, the data processing system includes a processor and a storage medium coupled to the processor, adapted to perform the steps according to one of the following conditions:

[0329] -When the discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 50% or more of the position to the discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 When the volume element is positioned at 66% or less of the positions, the volume element is positioned as described above with respect to the computer-implemented method;

[0330] - When the discrete x of the layer adjacent to the layer is to be m+3 ,y m+3 ,z m+3 ……x n+3 ,yn+3 ,z n+3 greater than 66% of the locations to the discrete x m+3 ,y m+3 ,z m+3 ……x n+3 ,y n+3 ,z n+3 When 75% or less of the positions locate the volume element, the volume element is located as described above with respect to the computer-implemented method;

[0331] - When the layer is to be separated from the adjacent layer by three layers, that is, the layer separated from the adjacent layer by the layer, the layer separated by one layer, and the layer adjacent to the layer separated by one layer, the discrete x m+4 ,y m+4 ,z m+4 ……x n+4 ,y n+4 ,z n+4 greater than 75% of the locations to the discrete x m+4 ,y m+4 ,z m+4 ……x n+4 ,y n+4 ,z n+4 When less than 80% of the positions locate a volume element, the volume element is located as described above with respect to the computer-implemented method.

[0332] In a preferred embodiment, the data processing system includes a processor and a storage medium coupled to the processor, adapted to perform the additional steps of:

[0333] (iii) Determine the discrete x of the adjacent layer m ,y m ,z m ……x n ,y n ,z n The actual value of the layer thickness at a position is the same as the discrete value of the adjacent layer x m ,y m ,z m ……x n ,y n ,z n The deviation of the layer thickness at a location from the default nominal value.

[0334] In a preferred embodiment, the data processing system includes a processor and a storage medium coupled to the processor, adapted to perform the additional steps of:

[0335] (iv) determining the sum of the deviation and the actual value of the layer thickness.

[0336] In a preferred embodiment, the data processing system includes a processor and a storage medium coupled to the processor, adapted to perform the steps according to one of the following conditions:

[0337] - when the sum is greater than half the default nominal value of the layer thickness, then no volume element is positioned at the discrete x value of the layer in the layer stack. m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Location;

[0338] - when the sum is less than or equal to half the default nominal value of the layer thickness, then locating a volume element at a discrete x value of the layer in the layer stack m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Location.

[0339] In a preferred embodiment, the data processing system includes a processor and a storage medium coupled to the processor, adapted to perform one of the additional steps selected from the following:

[0340] - determining said discrete x of said slice after said positioning of the volume elements m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The deviation of the layer thickness at the position is calculated from the default nominal value and the deviation is distributed to the adjacent discrete x values ​​in the same layer. o+1 ,y o+1 ,z o+1 ……x p+1 ,y p+1 ,z p+1 Location;

[0341] - determining said discrete x of said slice after said positioning of the volume elements m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The deviation of the layer thickness at position 1 from the default nominal value and transfers the deviation to the discrete x value of the layer at that interval m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2Location;

[0342] - determining said discrete x of said slice after said unpositioning of volume elements m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The deviation of the layer thickness at the position is calculated from the default nominal value and the deviation is distributed to the adjacent discrete x values ​​in the same layer. o+1 ,y o+1 ,z o+1 ……x p+1 ,y p+1 ,z p+1 Location;

[0343] - determining said discrete x of said slice after said unpositioning of volume elements m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The deviation of the layer thickness at position 1 from the default nominal value and transfers the deviation to the discrete x value of the layer at that interval m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 Location.

[0344] With respect to the data processing system, the above definition of computer-implemented method shall apply. The data processing system may be replaced by a computer and an inkjet printer, in which case the above definition of computer-implemented method shall also apply.

[0345] In a preferred embodiment, the present invention comprises a computer program comprising instructions which, when the program is executed by a computer, cause the computer to perform the above-described computer-implemented method.

[0346] The computer program may be stored on a non-transitory tangible computer-readable storage medium, the computer program comprising instructions which, when executed by a computer, cause the computer to perform the above-described computer-implemented method.

[0347] In a preferred embodiment, the present invention comprises a computer readable storage medium having stored thereon said computer program.The computer readable storage medium may be a non-transitory tangible computer readable storage medium.

[0348] In a preferred embodiment, the invention comprises a data signal carrying said computer program.

[0349] The data set of computer readable printing instructions according to the present invention is configured for inkjet printing of an eyeglass lens, the data set being (i) stored on a computer readable storage medium or (ii) transmitted via a data signal. The use of the data set is for inkjet printing of an eyeglass lens.

[0350] The data set includes printing instructions which have been generated as described above.

[0351] The inkjet printer according to the present invention comprises a processor configured to cause the inkjet print head to:

[0352] A) Discrete x in the layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Position release jet to form ink droplets, or

[0353] B) Discrete x not in the layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Position release jet to form ink droplets

[0354] In order to inkjet print ophthalmic lenses in layers, the release or non-release is based on the discrete x of adjacent layers. m ,y m ,z m ……x n ,y n ,z n Ink droplet positioning in.

[0355] When the eyeglass lens is finally inkjet printed, the (A) releasing or (B) non-releasing is completed.

[0356] In a preferred embodiment, the inkjet printer is configured to include steps according to one of the following conditions:

[0357] -When the discrete x m ,y m ,z m ……x n ,y n ,z n When less than 50% of the positions have ink droplets positioned, the ink droplets are not positioned at the discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Each of the positions;

[0358] -When the discrete x m ,y m ,z m ……x n ,y n ,z n When 50% or more of the positions are positioned with ink droplets, the ink droplets are partially positioned at the discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Location.

[0359] In a preferred embodiment, the inkjet printer is configured to include steps according to one of the following conditions:

[0360] -When the discrete x m ,y m ,z m ……x n ,y n ,z n When less than 50% of the positions have ink droplets positioned, the ink droplets are not positioned at the discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The ink droplets are positioned at each of the discrete x positions of each layer in the layer stack. m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 Each of the positions;

[0361] -When the discrete x m ,y m ,z m ……x n ,y n ,z n When 50% or more of the positions are positioned with ink droplets, the ink droplets are partially positioned at the discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 position, and partially locates the ink droplet at discrete x positions every other layer in the layer stack m+2 ,y m+2 ,z m+2 ……xn+2 ,y n+2 ,z n+2 Location.

[0362] In a preferred embodiment, the inkjet printer is configured to include steps according to one of the following conditions:

[0363] -When the discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 50% or more of the position to the discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 When the ink droplet is positioned at 66% or less of the positions, the ink droplet is positioned as described above with respect to the computer-implemented method;

[0364] - When the discrete x of the layer adjacent to the layer is to be m+3 ,y m+3 ,z m+3 ……x n+3 ,y n+3 ,z n+3 greater than 66% of the locations to the discrete x m+3 ,y m+3 ,z m+3 ……x n+3 ,y n+3 ,z n+3 When the ink droplet is positioned at 75% or less of the positions, the ink droplet is positioned as described above with respect to the computer-implemented method;

[0365] - When the layer is to be separated from the adjacent layer by three layers, that is, the layer separated from the adjacent layer by the layer, the layer separated by one layer, and the layer adjacent to the layer separated by one layer, the discrete x m+4 ,y m+4 ,z m+4 ……x n+4 ,y n+4 ,z n+4 greater than 75% of the locations to the discrete x m+4 ,y m+4 ,z m+4 ……x n+4 ,y n+4 ,z n+4 When less than 80% of the positions position the droplet, then the droplet is positioned as described above with respect to the computer-implemented method.

[0366] In a preferred embodiment, the inkjet printer is configured to include the additional steps of:

[0367] (C) Determine the discrete x of the adjacent layer m ,y m ,z m ……x n ,y n ,z n The actual value of the layer thickness at a position is the same as the discrete value of the adjacent layer x m ,y m ,z m ……x n ,y n ,z n The deviation of the layer thickness at a location from the default nominal value.

[0368] In a preferred embodiment, the inkjet printer is configured to include the additional steps of:

[0369] (D) Determining the sum of the deviation and the actual value of the layer thickness.

[0370] In a preferred embodiment, the inkjet printer is configured to include steps according to one of the following conditions:

[0371] - when the sum is greater than half the default nominal value of the layer thickness, then no ink drop is positioned at the discrete x of the layer in the layer stack. m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Location;

[0372] - when the sum is less than or equal to half the default nominal value of the layer thickness, then positioning the ink droplet at a discrete x value of the layer in the layer stack m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Location.

[0373] In a preferred embodiment, the inkjet printer is configured to include one of the additional steps selected from:

[0374] - determining said discrete x of said layer after said positioning of the ink droplets m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1The deviation of the layer thickness at the position is calculated from the default nominal value and the deviation is distributed to the adjacent discrete x values ​​in the same layer. o+1 ,y o+1 ,z o+1 ……x p+1 ,y p+1 ,z p+1 Location;

[0375] - determining said discrete x of said layer after said positioning of the ink droplets m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The deviation of the layer thickness at position 1 from the default nominal value and transfers the deviation to the discrete x value of the layer at that interval m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 Location;

[0376] - determining said discrete x of said layer after said de-positioning of an ink drop m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The deviation of the layer thickness at the position is calculated from the default nominal value and the deviation is distributed to the adjacent discrete x values ​​in the same layer. o+1 ,y o+1 ,z o+1 ……x p+1 ,y p+1 ,z p+1 Location;

[0377] - determining said discrete x of said layer after said de-positioning of an ink drop m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The deviation of the layer thickness at position 1 from the default nominal value and transfers the deviation to the discrete x value of the layer at that interval m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 Location.

[0378] With respect to the inkjet printer, the definitions given above with respect to the computer-implemented method shall apply.

[0379] The method for layered inkjet printing of ophthalmic lenses according to the present invention comprises one of the following steps:

[0380] a) Based on the discrete x of ink droplets on adjacent layers m ,y m ,z m ……x n ,y n ,z n Positioning, positioning the ink droplets at discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Location, or

[0381] b) Based on the discrete x of ink droplets on adjacent layers m ,y m ,z m ……x n ,y n ,z n Position positioning, do not position the ink droplets at discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Location.

[0382] According to the method, when the eyeglass lens is finally inkjet printed, (a) the positioning or (b) the non-positioning is completed.

[0383] In a preferred embodiment, the method comprises the steps according to one of the following conditions:

[0384] -When the discrete x m ,y m ,z m ……x n ,y n ,z n When less than 50% of the positions have ink droplets positioned, the ink droplets are not positioned at the discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Each of the positions;

[0385] -When the discrete x m ,y m ,z m ……x n ,y n ,zn When 50% or more of the positions are positioned with ink droplets, the ink droplets are partially positioned at the discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Location.

[0386] In a preferred embodiment, the method comprises the steps according to one of the following conditions:

[0387] -When the discrete x m ,y m ,z m ……x n ,y n ,z n When less than 50% of the positions have ink droplets positioned, the ink droplets are not positioned at the discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The ink droplets are positioned at each of the discrete x positions of each layer in the layer stack. m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 Each of the positions;

[0388] -When the discrete x m ,y m ,z m ……x n ,y n ,z n When 50% or more of the positions are positioned with ink droplets, the ink droplets are partially positioned at the discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 position, and partially locates the ink droplet at discrete x positions every other layer in the layer stack m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 Location.

[0389] In a preferred embodiment, the method comprises the steps according to one of the following conditions:

[0390] -When the discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 50% or more of the position to the discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 When the ink droplet is positioned at 66% or less of the positions, the ink droplet is positioned as described above with respect to the computer-implemented method;

[0391] - When the discrete x of the layer adjacent to the layer is to be m+3 ,y m+3 ,z m+3 ……x n+3 ,y n+3 ,z n+3 greater than 66% of the locations to the discrete x m+3 ,y m+3 ,z m+3 ……x n+3 ,y n+3 ,z n+3 When the ink droplet is positioned at 75% or less of the positions, the ink droplet is positioned as described above with respect to the computer-implemented method;

[0392] - When the layer is to be separated from the adjacent layer by three layers, that is, the layer separated from the adjacent layer by the layer, the layer separated by one layer, and the layer adjacent to the layer separated by one layer, the discrete x m+4 ,y m+4 ,z m+4 ……x n+4 ,y n+4 ,z n+4 greater than 75% of the locations to the discrete x m+4 ,y m+4 ,z m+4 ……x n+4 ,y n+4 ,z n+4 When less than 80% of the positions position the droplet, then the droplet is positioned as described above with respect to the computer-implemented method.

[0393] In a preferred embodiment, the method comprises the additional steps of:

[0394] (c) Determine the discrete x of the adjacent layer m ,y m ,z m ……x n,y n ,z n The actual value of the layer thickness at a position is the same as the discrete value of the adjacent layer x m ,y m ,z m ……x n ,y n ,z n The deviation of the layer thickness at a location from the default nominal value.

[0395] In a preferred embodiment, the method comprises the additional steps of:

[0396] (d) determining the sum of the deviation and the actual value of the layer thickness.

[0397] In a preferred embodiment, the method comprises the steps according to one of the following conditions:

[0398] - when the sum is greater than half the default nominal value of the layer thickness, then no ink drop is positioned at the discrete x of the layer in the layer stack. m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Location;

[0399] - when the sum is less than or equal to half the default nominal value of the layer thickness, then positioning the ink droplet at a discrete x value of the layer in the layer stack m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Location.

[0400] In a preferred embodiment, the method comprises one of the following additional steps:

[0401] - determining said discrete x of said layer after said positioning of the ink droplets m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The deviation of the layer thickness at the position is calculated from the default nominal value and the deviation is distributed to the adjacent discrete x values ​​in the same layer. o+1 ,y o+1 ,z o+1 ……x p+1 ,y p+1 ,z p+1 Location;

[0402] - determining said discrete x of said layer after said positioning of the ink droplets m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The deviation of the layer thickness at position 1 from the default nominal value and transfers the deviation to the discrete x value of the layer at that interval m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 Location;

[0403] - determining said discrete x of said layer after said de-positioning of an ink drop m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The deviation of the layer thickness at the position is calculated from the default nominal value and the deviation is distributed to the adjacent discrete x values ​​in the same layer. o+1 ,y o+1 ,z o+1 ……x p+1 ,y p+1 ,z p+1 Location;

[0404] - determining said discrete x of said layer after said de-positioning of an ink drop m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The deviation of the layer thickness at position 1 from the default nominal value and transfers the deviation to the discrete x value of the layer at that interval m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 Location.

[0405] Concerning said method, the definitions given above with respect to computer-implemented method shall apply.

[0406] In a preferred embodiment of the invention, the spatial extension of said layer and said adjacent layer are identical.

[0407] The same spatial extension means that, in plan view, the layer and the adjacent layer have the same size when projected in the plane determined by the x-direction and the y-direction. For example, when projected in the plane determined by the x-direction and the y-direction, in plan view, each layer and the adjacent layer form a circle, and the radius of each layer forming the circle is the same. Having the same size does not necessarily mean that, in plan view, an ink drop must be placed at every point of the perimeter of the projection when projected in the plane determined by the x-direction and the y-direction. However, the perimeter is preferably the maximum spatial extension that each layer has.

[0408] The spatial extension may be the spatial extension of the following eyeglass lenses:

[0409] - a spectacle lens intended for edging, i.e. a spectacle lens corresponding to an uncut lens as defined in section 3.8.8 of ISO 13666:2019(E) (finished lens before edging), or

[0410] - Spectacle lenses not intended for edging, i.e. spectacle lenses corresponding to edged lenses as defined in ISO 13666:2019(E), section 3.8.9 (finished lenses edged to their final size and shape).

[0411] In a preferred embodiment of the present invention, the outermost of the adjacent layers is inkjet printed in or on a substrate, the substrate defining the following lens surface:

[0412] - the front surface of the ophthalmic lens, or

[0413] - the rear surface of the ophthalmic lens.

[0414] In a preferred embodiment of the present invention, the total ink drop volume in each layer is preset.

[0415] The total drop volume is preset meaning that a total ink volume is preset for each layer, i.e. the total volume is inkjet printed in one layer. No volume from the total volume is inkjet printed in another layer. The total drop volume to be positioned in a layer is equal to the volume of the layer.

[0416] Figure 1 A flow chart is shown which comprises a preferred embodiment of the computer implemented method.

[0417] Figure 2The results of positioning on a linear gradient structure are shown. In the upper part, the layer thickness is zero, so no volume elements are positioned, which represent the ink drops to be inkjet printed. In the lower part, all layers are to be inkjet printed with their maximum thickness, so all ink drops are inkjet printed, and all volume elements representing all ink drops are positioned. In the 50% area, the layer is to be inkjet printed with half of the maximum thickness, so only half of the ink drops will be inkjet printed here, and only half of the volume elements representing half of the ink drops are positioned. Here, the positioning of the volume elements in the second layer is complementary to the positioning of the volume elements in the first layer. Here, the positioning of the volume elements in the fourth layer is complementary to the positioning of the volume elements in the second layer. The positioning of the volume elements in the third layer may not be complementary to the positioning of the volume elements in the second layer. This is because at this discrete position, the deviation of the layer thickness of the first layer has been balanced by the relative volume element positioning of the second layer. This means that the volume elements in the third layer at this discrete position are mainly positioned here to minimize the distance change to the volume elements in the same layer.

[0418] In the 25% region, it can be observed that only one volume element is located at each position distributed over all four layers. In the 75% region, it can be observed that three volume elements are located at each position distributed over all four layers.

Claims

1. A computer-implemented method configured for computing a digital twin of an ophthalmic lens for use in the manufacture of the ophthalmic lens, the digital twin comprising a layer stack, wherein one of the following conditions applies: - When the discrete x of adjacent layers in the layer stack m ,y m ,z m ……x n ,y n ,z n If 50% or less of the positions have volume elements positioned therein, no volume elements are positioned at the discrete x positions of the layers in the layer stack. m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The position of the layer is discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The position and the corresponding discrete x of the adjacent layer m ,y m ,z m ……x n ,y n ,z n Positioned directly adjacent to and on top of; - When the discrete x of adjacent layers in the layer stack m ,y m ,z m ……x n ,y n ,z n If more than 50% of the positions have volume elements positioned, the volume elements are positioned at at least one of the following positions: ○ The discreteness x of the layers in the layer stack m+1a……z ,y m+1a……z ,z m+1a……z ……x n+1a……z ,y n+1a……z ,z n+1a……z The position of the layer is discrete x m+1a……z ,y m+1a……z ,z m+1a……z ……x n+1a……z ,y n+1a……z ,z n+1a……z The position and the corresponding discrete x of the adjacent layer m ,y m ,z m ……x n ,y n ,z n The position is not directly adjacent to and is not located on top of it, ○ The discreteness x of the layers in the layer stack m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The position of the layer is discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The position and the corresponding discrete x of the adjacent layer m ,y m ,z m ……x n ,y n ,z n Positioned directly adjacent to and on top of it.

2. The method according to claim 1, characterized in that One of the following conditions applies: -When the discrete x m ,y m ,z m ……x n ,y n ,z n If less than 50% of the positions have volume elements positioned, no volume elements are positioned at the discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Each of the positions is positioned at a discrete x position in the layer stack. m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 Each of the positions; -When the discrete x m ,y m ,z m ……x n ,y n ,z n When 50% or more of the positions have volume elements positioned, the volume elements are partially positioned at the following positions: ○The discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Location ○ The discrete x of each layer in the layer stack m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 Location, The discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 The position and the discrete x of the layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Positioned directly adjacent to and on top of it.

3. The method according to any one of the preceding claims, characterized in that The following conditions apply: -When the discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 50% or more of the position to the discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 When the volume element is positioned at 66% or less of the position, the volume element is positioned at the following positions: a. Discrete x m+2b ,y m+2b ,z m+2b ……x n+2b ,y n+2b ,z n+2b position, thus the discrete x of the layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The volume element of the position is not adjacent to and is not located on top of it, and is not located in the discrete x of the adjacent layer m ,y m ,z m ……x n ,y n ,z n The top of the volume element of the location, or b. Discrete x m+2a ,y m+2a ,z m+2a ……x n+2a ,y n+2a ,z n+2a position, thus the discrete x of the layer m+1a ,y m+1a ,z m+1a ……x n+1a ,y n+1a ,z n+1a The volume element of the position is adjacent to and located on top of it, and is not located in the discrete x of the adjacent layer m ,y m ,z m ……x n ,y n ,z n The top of the volume element of the location, or c. Discrete x m+2b ,y m+2b ,z m+2b ……x n+2b ,y n+2b ,z n+2b position, thus the discrete x of the layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The volume element of the position is not adjacent to and is not located on top of it, and is located in the discrete x of the adjacent layer mb ,y mb ,z mb ……x nb ,y nb ,z nb The top of the volume element of the location, or d. Discrete x m+2a ,y m+2a ,z m+2a ……x n+2a ,y n+2a ,z n+2a position, thus the discrete x of the layer m+1a ,y m+1a ,z m+1a ……x n+1a ,y n+1a ,z n+1a The volume element of the position is adjacent to and located on top of it, and the discrete x ma ,y ma ,z ma ……x na ,y na ,z na The top of the volume element of the location.

4. The method according to any one of the preceding claims, characterized in that The following conditions apply: - When the discrete x of the layer adjacent to the layer is to be m+3 ,y m+3 ,z m+3 ……x n+3 ,y n+3 ,z n+3 greater than 66% of the locations to the discrete x m+3 ,y m+3 ,z m+3 ……x n+3 ,y n+3 ,z n+3 When the volume element is positioned at 75% or less than 75% of the position, the volume element is positioned at the following positions: a. Discrete x m+3b ,y m+3b ,z m+3b ……x n+3b ,y n+3b ,z n+3b position, thus separating the discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 The volume element of the position is not adjacent to and is not located on top of it, and is not located in the discrete x of the layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The discrete x on top of the volume element of the position and not located in the adjacent layer m ,y m ,z m ……x n ,y n ,z n The top of the volume element of the location, or b. Discrete x m+3b ,y m+3b ,z m+3b ……x n+3b ,y n+3b ,z n+3b position, thus separating the discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 The volume element of the position is not adjacent to and is not located on top of it, and is not located in the discrete x of the layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The volume element at the top of the position and the discrete x at the adjacent layer mb ,y mb ,z mb ……x nb ,y nb ,z nb The top of the volume element of the location, or c. Discrete x m+3b ,y m+3b ,z m+3b ……x n+3b ,y n+3b ,z n+3b position, thus separating the discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 The volume element of the position is not adjacent to and is not located on top of it and is located at the discrete x of the layer m+1b ,y m+1b ,z m+1b ……x n+1b ,y n+1b ,z n+1b The discrete x on top of the volume element of the position and not located in the adjacent layer m ,y m ,z m ……x n ,y n ,z n The top of the volume element of the location, or d. Discrete x m+3a ,y m+3a ,z m+3a ……x n+3a ,y n+3a ,z n+3a position, thus separating the discrete x m+2a ,y m+2a ,z m+2a ……x n+2a ,y n+2a ,z n+2a The volume element of the position is adjacent to and located on top of it and is not located in the discrete x layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The discrete x on top of the volume element of the position and not located in the adjacent layer m ,y m ,z m ……x n ,y n ,z n The top of the volume element of the location, or e. Discrete x m+3a ,y m+3a ,z m+3a ……x n+3a ,y n+3a ,z n+3a position, thus separating the discrete x m+2a ,y m+2a ,z m+2a ……x n+2a ,y n+2a ,z n+2a The volume element of the position is adjacent to and located on top of it and is not located in the discrete x layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The volume element at the top of the position and the discrete x at the adjacent layer ma ,y ma ,z ma ……x na ,y na ,z na The top of the volume element of the location, or f. Discrete x m+3a ,y m+3a ,z m+3a ……x n+3a ,y n+3a ,z n+3a position, thus separating the discrete x m+2a ,y m+2a ,z m+2a ……x n+2a ,y n+2a ,z n+2a The volume element of the position is adjacent to and located on top of it and is located at the discrete x m+1a ,y m+1a ,z m+1a ……x n+1a ,y n+1a ,z n+1a The discrete x on top of the volume element of the position and not located in the adjacent layer ma ,y ma ,z ma ……x na ,y na ,z na The top of the volume element of the location, or g. Discrete x m+3b ,y m+3b ,z m+3b ……x n+3b ,y n+3b ,z n+3b position, thus separating the discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 The volume element of the position is not adjacent to and is not located on top of it and is located at the discrete x of the layer m+1b ,y m+1b ,z m+1b ……x n+1b ,y n+1b ,z n+1b The volume element at the top of the position and the discrete x at the adjacent layer mb ,y mb ,z mb ……x nb ,y nb ,z nb The top of the volume element of the location, or h. Discrete x m+3a ,y m+3a ,z m+3a ……x n+3a ,y n+3a ,z n+3a position, thus separating the discrete x m+2a ,y m+2a ,z m+2a ……x n+2a ,y n+2a ,z n+2a The volume element of the position is adjacent to and located on top of it and is located at the discrete x m+1a ,y m+1a ,z m+1a ……x n+1a ,y n+1a ,z n+1a The volume element at the top of the position and the discrete x at the adjacent layer ma ,y ma ,z ma ……x na ,y na ,z na The top of the volume element of the location.

5. The method according to any one of the preceding claims, characterized in that The following conditions apply: - When the layer is to be separated from the adjacent layer by three layers, that is, the layer separated from the adjacent layer by the layer, the layer separated by one layer, and the layer adjacent to the layer separated by one layer, the discrete x m+4 ,y m+4 ,z m+4 ……x n+4 ,y n+4 ,z n+4 greater than 75% of the locations to the discrete x m+4 ,y m+4 ,z m+4 ……x n+4 ,y n+4 ,z n+4 When the volume element is positioned at less than 80% of the position, the volume element is positioned at the following positions: a. Discrete x m+4b ,y m+4b ,z m+4b ……x n+4b ,y n+4b ,z n+4b position, thus the discrete x of the layer adjacent to the layer m+3 ,y m+3 ,z m+3 ……x n+3 ,y n+3 ,z n+3 The volume element of the position is not adjacent to and is not located on top of it, and is not located in the discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 The discrete x of the volume element of the position and not located in the layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The discrete x on top of the volume element of the position and not located in the adjacent layer m ,y m ,z m ……x n ,y n ,z n The top of the volume element of the location, or b. Discrete x m+4b ,y m+4b ,z m+4b ……x n+4b ,y n+4b ,z n+4b position, thus the discrete x of the layer adjacent to the layer m+3 ,y m+3 ,z m+3 ……x n+3 ,y n+3 ,z n+3 The volume element of the position is not adjacent to and is not located on top of it, and is not located in the discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 The discrete x of the volume element of the position and not located in the layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The volume element at the top of the position and the discrete x at the adjacent layer m ,y m ,z m ……x n ,y n ,z n The top of the volume element of the location, or c. Discrete x m+4b ,y m+4b ,z m+4b ……x n+4b ,y n+4b ,z n+4b position, thus the discrete x of the layer adjacent to the layer m+3 ,y m+3 ,z m+3 ……x n+3 ,y n+3 ,z n+3 The volume element of the position is not adjacent to and is not located on top of it, and is not located in the discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 The volume element of the position is located on top of the discrete x m+1b ,y m+1b ,z m+1b ……x n+1b ,y n+1b ,z n+1b The discrete x on top of the volume element of the position and not located in the adjacent layer m ,y m ,z m ……x n ,y n ,z n The top of the volume element of the location, or d. Discrete x m+4b ,y m+4b ,z m+4b ……x n+4b ,y n+4b ,z n+4b position, thus the discrete x of the layer adjacent to the layer m+3 ,y m+3 ,z m+3 ……x n+3 ,y n+3 ,z n+3 The volume element of the position is not adjacent to and is not located on top of it, and is located at the discrete x m+2b ,y m+2b ,z m+2b ……x n+2b ,y n+2b ,z n+2b The discrete x of the volume element of the position and not located in the layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The discrete x on top of the volume element of the position and not located in the adjacent layer m ,y m ,z m ……x n ,y n ,z n The top of the volume element of the location, or e. Discrete x m+4a ,y m+4a ,z m+4a ……x n+4a ,y n+4a ,z n+4a position, thus the discrete x of the layer adjacent to the layer m+3a ,y m+3a ,z m+3a ……x n+3a ,y n+3a ,z n+3a The volume element of the position is adjacent to and located on top of it, and is not located in the discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 The discrete x of the volume element of the position and not located in the layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The discrete x on top of the volume element of the position and not located in the adjacent layer m ,y m ,z m ……x n ,y n ,z n The top of the volume element of the location, or f. Discrete x m+4b ,y m+4b ,z m+4b ……x n+4b ,y n+4b ,z n+4b position, thus the discrete x of the layer adjacent to the layer m+3 ,y m+3 ,z m+3 ……x n+3 ,y n+3 ,z n+3 The volume element of the position is not adjacent to and is not located on top of it, and is not located in the discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 The volume element of the position is located on top of the discrete x m+1b ,y m+1b ,z m+1b ……x n+1b ,y n+1b ,z n+1b The volume element at the top of the position and the discrete x at the adjacent layer mb ,y mb ,z mb ……x nb ,y nb ,z nb The top of the volume element of the location, or g. Discrete x m+4b ,y m+4b ,z m+4b ……x n+4b ,y n+4b ,z n+4b position, thus the discrete x of the layer adjacent to the layer m+3 ,y m+3 ,z m+3 ……x n+3 ,y n+3 ,z n+3 The volume element of the position is not adjacent to and is not located on top of it, and is located at the discrete x m+2b ,y m+2b ,z m+2b ……x n+2b ,y n+2b ,z n+2b The discrete x of the volume element of the position and not located in the layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The volume element at the top of the position and the discrete x at the adjacent layer mb ,y mb ,z mb ……x nb ,y nb ,z nb The top of the volume element of the location, or h. Discrete x m+4b ,y m+4b ,z m+4b ……x n+4b ,y n+4b ,z n+4b position, thus the discrete x of the layer adjacent to the layer m+3 ,y m+3 ,z m+3 ……x n+3 ,y n+3 ,z n+3 The volume element of the position is not adjacent to and is not located on top of it, and is located at the discrete x m+2b ,y m+2b ,z m+2b ……x n+2b ,y n+2b ,z n+2b The volume element of the position is located on top of the discrete x m+1b ,y m+1b ,z m+1b ……x n+1b ,y n+1b ,z n+1b The discrete x on top of the volume element of the position and not located in the adjacent layer m ,y m ,z m ……x n ,y n ,z n The top of the volume element of the location, or i. Discrete x m+4a ,y m+4a ,z m+4a ……x n+4a ,y n+4a ,z n+4a position, thus the discrete x of the layer adjacent to the layer m+3a ,y m+3a ,z m+3a ……x n+3a ,y n+3a ,z n+3a The volume element of the position is adjacent to and located on top of it, and is not located in the discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 The volume element of the position is located on top of the discrete x m+1a ,y m+1a ,z m+1a ……x n+1a ,y n+1a ,z n+1a The discrete x on top of the volume element of the position and not located in the adjacent layer m ,y m ,z m ……x n ,y n ,z n The top of the volume element of the location, or j. Discrete x m+4a ,y m+4a ,z m+4a ……x n+4a ,y n+4a ,z n+4a position, thus the discrete x of the layer adjacent to the layer m+3a ,y m+3a ,z m+3a ……x n+3a ,y n+3a ,z n+3a The volume element of the position is adjacent to and located on top of it, and is located at the discrete x m+2a ,y m+2a ,z m+2a ……x n+2a ,y n+2a ,z n+2a The discrete x of the volume element of the position and not located in the layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The discrete x on top of the volume element of the position and not located in the adjacent layer m ,y m ,z m ……x n ,y n ,z n The top of the volume element of the location, or k. Discrete x m+4a ,y m+4a ,z m+4a ……x n+4a ,y n+4a ,z n+4a position, thus the discrete x of the layer adjacent to the layer m+3a ,y m+3a ,z m+3a ……x n+3a ,y n+3a ,z n+3a The volume element of the position is adjacent to and located on top of it, and is not located in the discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 The volume element of the position is located on top of the discrete x m+1a ,y m+1a ,z m+1a ……x n+1a ,y n+1a ,z n+1a The discrete x on top of the volume element of the position and not located in the adjacent layer m ,y m ,z m ……x n ,y n ,z n The top of the volume element of the location, or l. Discrete x m+4b ,y m+4b ,z m+4b ……x n+4b ,y n+4b ,z n+4b position, thus the discrete x of the layer adjacent to the layer m+3 ,y m+3 ,z m+3 ……x n+3 ,y n+3 ,z n+3 The volume element of the position is not adjacent to and is not located on top of it, and is located at the discrete x m+2b ,y m+2b ,z m+2b ……x n+2b ,y n+2b ,z n+2b The volume element of the position is located on top of the discrete x m+1b ,y m+1b ,z m+1b ……x n+1b ,y n+1b ,z n+1b The volume element at the top of the position and the discrete x at the adjacent layer mb ,y mb ,z mb ……x nb ,y nb ,z nb The top of the volume element of the location, or m. Discrete x m+4a ,y m+4a ,z m+4a ……x n+4a ,y n+4a ,z n+4a position, thus the discrete x of the layer adjacent to the layer m+3a ,y m+3a ,z m+3a ……x n+3a ,y n+3a ,z n+3a The volume element of the position is adjacent to and located on top of it, and is not located in the discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 The discrete x of the volume element of the position and not located in the layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The volume element at the top of the position and the discrete x at the adjacent layer ma ,y ma ,z ma ……x na ,y na ,z na The top of the volume element of the location, or discrete x m+4a ,y m+4a ,z m+4a ……x n+4a ,y n+4a ,z n+4a position, thus the discrete x of the layer adjacent to the layer m+3a ,y m+3a ,z m+3a ……x n+3a ,y n+3a ,z n+3a The volume element of the position is adjacent to and located on top of it, and is located at the discrete x m+2a ,y m+2a ,z m+2a ……x n+2a ,y n+2a ,z n+2a The discrete x of the volume element of the position and not located in the layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The volume element at the top of the position and the discrete x at the adjacent layer ma ,y ma ,z ma ……x na ,y na ,z na The top of the volume element of the location, or o. Discrete x m+4a ,y m+4a ,z m+4a ……x n+4a ,y n+4a ,z n+4a position, thus the discrete x of the layer adjacent to the layer m+3a ,y m+3a ,z m+3a ……x n+3a ,y n+3a ,z n+3a The volume element of the position is adjacent to and located on top of it, and is located at the discrete x m+2a ,y m+2a ,z m+2a ……x n+2a ,y n+2a ,z n+2a The volume element of the position is located on top of the discrete x m+1a ,y m+1a ,z m+1a ……x n+1a ,y n+1a ,z n+1a The discrete x on top of the volume element of the position and not located in the adjacent layer m ,y m ,z m ……x n ,y n ,z n The top of the volume element of the location, or p. Discrete x m+4a ,y m+4a ,z m+4a ……x n+4a ,y n+4a ,z n+4a position, thus the discrete x of the layer adjacent to the layer m+3a ,y m+3a ,z m+3a ……x n+3a ,y n+3a ,z n+3a The volume element of the position is adjacent to and located on top of it, and is located at the discrete x m+2a ,y m+2a ,z m+2a ……x n+2a ,y n+2a ,z n+2a The volume element of the position is located on top of the discrete x m+1a ,y m+1a ,z m+1a ……x n+1a ,y n+1a ,z n+1a The volume element at the top of the position and the discrete x at the adjacent layer ma ,y ma ,z ma ……x na ,y na ,z na The top of the volume element of the location.

6. A method according to any one of the preceding claims, characterised in that The following additional steps: (i) Determine the discrete x of the adjacent layer m ,y m ,z m ……x n ,y n ,z n The actual value of the layer thickness at a position is the same as the discrete value of the adjacent layer x m ,y m ,z m ……x n ,y n ,z n The deviation [102] of the default nominal value [101] of the layer thickness at the location.

7. The method according to claim 6, characterized in that The following additional steps: (ii) determining the sum of the deviation of the layer thickness and the actual value [103].

8. A computer-implemented method configured for computing a digital twin of an ophthalmic lens for use in the manufacture of the ophthalmic lens, the digital twin comprising a layer stack, the method being characterized by the following steps: - determining the sum of the deviation of the layer thickness [102] and the actual value of the layer thickness [103], The deviation [102] is the discrete x of adjacent layers. m ,y m ,z m ……x n ,y n ,z n The actual value of the layer thickness at a position is the same as the discrete value of the adjacent layer x m ,y m ,z m ……x n ,y n ,z n The deviation of the layer thickness at the location from the default nominal value [101].

9. The method according to claim 8, characterized in that One of the following conditions applies: -When the discrete x m ,y m ,z m ……x n ,y n ,z n If less than 50% of the positions have volume elements positioned, no volume elements are positioned at the discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Each of the positions; -When the discrete x m ,y m ,z m ……x n ,y n ,z n If 50% or more of the positions are located with volume elements, the volume elements are partially located at the discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Location.

10. The method according to any one of claims 8 and 9, characterized in that One of the following conditions applies: -When the discrete x m ,y m ,z m ……x n ,y n ,z n If less than 50% of the positions have volume elements positioned, no volume elements are positioned at the discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Each of the positions is positioned at a discrete x position in the layer stack. m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 Each of the positions; -When the discrete x m ,y m ,z m ……x n ,y n ,z n When 50% or more of the positions have volume elements positioned, the volume elements are partially positioned at the following positions: ○The discrete x m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Location ○ The discrete x of each layer in the layer stack m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 Location, The discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 The position and the discrete x of the layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Positioned directly adjacent to and on top of it.

11. The method according to any one of claims 8 to 10, characterized in that The following conditions apply: -When the discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 50% or more of the position to the discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 When the volume element is positioned at 66% or less of the position, the volume element is positioned at the following positions: a. Discrete x m+2b ,y m+2b ,z m+2b ……x n+2b ,y n+2b ,z n+2b position, thus the discrete x of the layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The volume element of the position is not adjacent to and is not located on top of it, and is not located in the discrete x of the adjacent layer m ,y m ,z m ……x n ,y n ,z n The top of the volume element of the location, or b. Discrete x m+2a ,y m+2a ,z m+2a ……x n+2a ,y n+2a ,z n+2a position, thus the discrete x of the layer m+1a ,y m+1a ,z m+1a ……x n+1a ,y n+1a ,z n+1a The volume element of the position is adjacent to and located on top of it, and is not located in the discrete x of the adjacent layer m ,y m ,z m ……x n ,y n ,z n The top of the volume element of the location, or c. Discrete x m+2b ,y m+2b ,z m+2b ……x n+2b ,y n+2b ,z n+2b position, thus the discrete x of the layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The volume element of the position is not adjacent to and is not located on top of it, and is located in the discrete x of the adjacent layer mb ,y mb ,z mb ……x nb ,y nb ,z nb The top of the volume element of the location, or d. Discrete x m+2a ,y m+2a ,z m+2a ……x n+2a ,y n+2a ,z n+2a position, thus the discrete x of the layer m+1a ,y m+1a ,z m+1a ……x n+1a ,y n+1a ,z n+1a The volume element of the position is adjacent to and located on top of it, and the discrete x ma ,y ma ,z ma ……x na ,y na ,z na The top of the volume element of the location.

12. The method according to any one of claims 8 to 11, characterized in that The following conditions apply: - When the discrete x of the layer adjacent to the layer is to be m+3 ,y m+3 ,z m+3 ……x n+3 ,y n+3 ,z n+3 greater than 66% of the locations to the discrete x m+3 ,y m+3 ,z m+3 ……x n+3 ,y n+3 ,z n+3 When the volume element is positioned at 75% or less than 75% of the position, the volume element is positioned at the following positions: a. Discrete x m+3b ,y m+3b ,z m+3b ……x n+3b ,y n+3b ,z n+3b position, thus separating the discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 The volume element of the position is not adjacent to and is not located on top of it, and is not located in the discrete x of the layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The discrete x on top of the volume element of the position and not located in the adjacent layer m ,y m ,z m ……x n ,y n ,z n The top of the volume element of the location, or b. Discrete x m+3b ,y m+3b ,z m+3b ……x n+3b ,y n+3b ,z n+3b position, thus separating the discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 The volume element of the position is not adjacent to and is not located on top of it, and is not located in the discrete x of the layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The volume element at the top of the position and the discrete x at the adjacent layer mb ,y mb ,z mb ……x nb ,y nb ,z nb The top of the volume element of the location, or c. Discrete x m+3b ,y m+3b ,z m+3b ……x n+3b ,y n+3b ,z n+3b position, thus separating the discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 The volume element of the position is not adjacent to and is not located on top of it and is located at the discrete x of the layer m+1b ,y m+1b ,z m+1b ……x n+1b ,y n+1b ,z n+1b The discrete x on top of the volume element of the position and not located in the adjacent layer m ,y m ,z m ……x n ,y n ,z n The top of the volume element of the location, or d. Discrete x m+3a ,y m+3a ,z m+3a ……x n+3a ,y n+3a ,z n+3a position, thus separating the discrete x m+2a ,y m+2a ,z m+2a ……x n+2a ,y n+2a ,z n+2a The volume element of the position is adjacent to and located on top of it and is not located in the discrete x layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The discrete x on top of the volume element of the position and not located in the adjacent layer m ,y m ,z m ……x n ,y n ,z n The top of the volume element of the location, or e. Discrete x m+3a ,y m+3a ,z m+3a ……x n+3a ,y n+3a ,z n+3a position, thus separating the discrete x m+2a ,y m+2a ,z m+2a ……x n+2a ,y n+2a ,z n+2a The volume element of the position is adjacent to and located on top of it and is not located in the discrete x layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The volume element at the top of the position and the discrete x at the adjacent layer ma ,y ma ,z ma ……x na ,y na ,z na The top of the volume element of the location, or f. Discrete x m+3a ,y m+3a ,z m+3a ……x n+3a ,y n+3a ,z n+3a position, thus separating the discrete x m+2a ,y m+2a ,z m+2a ……x n+2a ,y n+2a ,z n+2a The volume element of the position is adjacent to and located on top of it and is located at the discrete x m+1a ,y m+1a ,z m+1a ……x n+1a ,y n+1a ,z n+1a The discrete x on top of the volume element of the position and not located in the adjacent layer ma ,y ma ,z ma ……x na ,y na ,z na The top of the volume element of the location, or g. Discrete x m+3b ,y m+3b ,z m+3b ……x n+3b ,y n+3b ,z n+3b position, thus separating the discrete x m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 The volume element of the position is not adjacent to and is not located on top of it and is located at the discrete x of the layer m+1b ,y m+1b ,z m+1b ……x n+1b ,y n+1b ,z n+1b The volume element at the top of the position and the discrete x at the adjacent layer mb ,y mb ,z mb ……x nb ,y nb ,z nb The top of the volume element of the location, or h. Discrete x m+3a ,y m+3a ,z m+3a ……x n+3a ,y n+3a ,z n+3a position, thus separating the discrete x m+2a ,y m+2a ,z m+2a ……x n+2a ,y n+2a ,z n+2a The volume element of the position is adjacent to and located on top of it and is located at the discrete x m+1a ,y m+1a ,z m+1a ……x n+1a ,y n+1a ,z n+1a The volume element at the top of the position and the discrete x at the adjacent layer ma ,y ma ,z ma ……x na ,y na ,z na The top of the volume element of the location.

13. The method according to any one of claims 7 and 8, characterized in that One of the following conditions applies: - when the sum is greater than [104] half of the default nominal value of the layer thickness, then no volume element is positioned at the discrete x of the layer in the layer stack m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Position [106]; - when the sum is less than or equal to [105] half of the default nominal value of the layer thickness, then a volume element is positioned at a discrete x value of the layer in the layer stack m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Location[107].

14. The method according to claim 13, characterized in that Select one of the following additional steps: - determining said discrete x of said slice after said positioning of the volume elements m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The deviation [108] of the default nominal value of the layer thickness at the position and distributing [109] the deviation to adjacent discrete x in the same layer o+1 ,y o+1 ,z o+1 ……x p+1 ,y p+1 ,z p+1 Location; - determining said discrete x of said slice after said positioning of the volume elements m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The deviation of the layer thickness at the position [108] from the default nominal value and transferring [110] the deviation to the discrete x layer one layer away m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 Location; - determining said discrete x of said slice after said unpositioning of volume elements m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The deviation [108] of the default nominal value of the layer thickness at the position and distributing [109] the deviation to adjacent discrete x in the same layer o+1 ,y o+1 ,z o+1 ……x p+1 ,y p+1 ,z p+1 Location; - determining said discrete x of said slice after said unpositioning of volume elements m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The deviation of the layer thickness at the position [108] from the default nominal value and transferring [110] the deviation to the discrete x layer one layer away m+2 ,y m+2 ,z m+2 ……x n+2 ,y n+2 ,z n+2 Location.

15. A computer-implemented method configured for computing a digital twin of an ophthalmic lens for use in manufacturing the ophthalmic lens, the digital twin having a front surface and a back surface, the method being characterized by the following steps: - Calculate each discrete z of the front surface 前 The (x,y) position corresponds to the discrete z 后 The total number of volume elements between the (x, y) positions, the calculation results in the volume element density distribution of the digital twin.

16. The method according to claim 16, characterized by the following steps: - determining a minimum number of layers to be comprised by the layer stack based on a calculated maximum total number of volume elements between discrete x, y, z positions of the front surface and corresponding discrete x, y, z positions of the back surface.

17. The method according to any one of the preceding claims 16 and 17, characterized by the following steps: - uniformly distribute the volume elements in the following directions based on the calculated total number of volume elements: ○ The z direction for each corresponding x,y,z position, and o The x,y directions of each layer in the layer stack.

18. A method according to any one of the preceding claims, characterised in that Each layer in the layer stack has the same spatial extension when projected in the plane defined by the x-direction and the y-direction.

19. A computer, the computer being configured to perform the following steps: -Determine the volume element positioning in the layers of the layer stack of the digital twin: (iii) Discrete x of adjacent layers in the layer stack based on volume elements m ,y m ,z m ……x n ,y n ,z n Positioning, positioning the volume element at the discrete x of the layer in the layer stack m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Location, or (iv) discrete x of adjacent layers in the layer stack based on volume elements m ,y m ,z m ……x n ,y n ,z n Positioning, not positioning the volume element at the discrete x of the layer in the layer stack m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Location, The discrete x of the layer m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 The position and the discrete x of the adjacent layer m ,y m ,z m ……x n ,y n ,z n Located directly adjacent to and on top of it, Subject to the following conditions: When the discrete x m ,y m ,z m ……x n ,y n ,z n If 50% or less of the positions have volume elements positioned, no volume elements are positioned at the discrete x position of the layer. m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Location; When the discrete x m ,y m ,z m ……x n ,y n ,z n If more than 50% of the positions are located with volume elements, then the volume elements are partially located at the discrete x of the layer. m+1 ,y m+1 ,z m+1 ……x n+1 ,y n+1 ,z n+1 Location, And the inkjet printer prints the eyeglass lens according to the conditions.

20. A computer program comprising instructions which, when executed by a computer, cause the computer to perform the method according to any one of claims 1 to 18.

21. A computer-readable storage medium having stored thereon the computer program according to claim 20.

22. A data signal carrying a computer program according to claim 20.

23. The method according to any of the preceding claims 1 to 18, further configured to manufacture an ophthalmic lens based on the digital twin of the ophthalmic lens.

24. The method according to claim 23, characterized in that The spatial extension of the layer and the adjacent layers is the same.

25. The method according to any one of the preceding claims 23 and 24, characterized in that The outermost of the adjacent layers is inkjet printed in or on a substrate, the substrate defining a lens surface as follows: - the front surface of the ophthalmic lens, or - the rear surface of the ophthalmic lens.

26. The method according to any one of the preceding claims 23 to 25, characterized in that The total drop volume in the layer is preset.

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