Method and apparatus for optimizing eyeglass lenses, in particular for wearers of an implanted intraocular lens

Abstract

The invention relates to a method, a device and a corresponding computer program product for optimizing an eyeglass lens of a wearer of an implanted intraocular lens. Here, the method comprises the following steps: - providing individual refraction data of the at least one eye of an eyewear wearer; - defining an individual eye model, wherein at least the following are defined as parameters of the individual eye model: - - a shape and / or a refractive power of a cornea of a model eye (12), in particular a shape and / or a refractive power of a cornea front surface (18); - - a cornea-lens distance; - - parameters of a lens of the model eye; - - a lens-to-retina distance. Here, defining the parameters of the individual eye model is performed based on data of a vision correction of the at least one eye with the intraocular lens and further based on individual measurements and / or standard values of the eye of the eyewear wearer and / or based on the provided individual refraction data, so that the model eye (12) has the provided individual refraction data.

Description

TECHNICAL FIELD

[0001] The present invention relates to a method, a device and a corresponding computer program product for determining relevant individual parameters of at least one eye of a spectacle wearer for the calculation or optimization of a spectacle lens for the at least one eye of the spectacle wearer, and to a corresponding method, device and computer program product for calculating (optimizing) and manufacturing a spectacle lens with the help of a partial individual eye model. Here, the at least one eye of the spectacle wearer has an implanted intraocular lens (IOL). For example, instead of or in addition to a natural eye lens, an artificial lens can be implanted in the at least one eye during surgery. In other words, the spectacle wearer is a wearer of an implanted intraocular lens. Furthermore, the present invention relates to a method, a device and a corresponding computer program product for calculating (optimizing) and manufacturing a spectacle lens, in particular a spectacle lens for a wearer of an implanted intraocular lens, with the help of a partial individual eye model. BACKGROUND

[0002] For manufacturing or optimizing a spectacle lens, in particular an individual spectacle lens, each spectacle lens is manufactured such that for each desired direction of observation or each desired object point, the best possible correction of the refractive error of the respective eye of the spectacle wearer is achieved. Generally, a spectacle lens is considered to be completely corrected for a given direction of observation if the values of the wavefront's sphere, cylinder and axis at the vertex sphere coincide with the values of the sphere, cylinder and axis of the prescription of the eye in which the vision impairment exists. In determining the refractive power of the eye of the spectacle wearer, for a distance (usually infinite) and, for multifocal or progressive lenses, optionally an additional or complete near refraction (for example, according to DIN 58208) for near distances is determined (in particular sphere, cylinder, cylinder axis - i.e., in particular the spherical cylinder deviation). In the case of modern spectacle lenses, it is also possible to specify a standard deviating object distance, which is used to determine the refractive power. In this way, the prescription to be conveyed to the lens manufacturer is specified (in particular sphere, cylinder, cylinder axis and optionally additional or near refraction). Here, knowledge of the special or individual anatomy of the respective eye or of the refractive power values of the eye in which the vision impairment exists, which actually exists in individual cases, is not required.

[0003] However, it is generally not possible to completely correct all directions of observation at the same time. Therefore, spectacle lenses are manufactured such that they correct the vision impairment of the eye well and only produce small aberrations in the main area of use, in particular in the central vision area, while allowing larger aberrations in the peripheral area.

[0004] In order to be able to manufacture spectacle lenses in this way, first a spectacle lens surface or at least one spectacle lens surface is calculated, which achieves a desired distribution of unavoidable aberrations. This calculation and optimization is usually carried out by means of an iterative variation method by minimizing an objective function. As objective function, inter alia, a function F is considered which has the following functional relationship to the size of the spherical power S, the cylindrical power Z and the cylindrical axis A (also referred to as "SZA" combination) and which is minimized:

[0005]

[0006] In the objective function F, at the evaluation points i of the spectacle lens, at least the actual power difference of the spherical power S Δ,i and the cylindrical power Z Δ,i as well as the target specification of the power difference of the spherical power S Δ,i,target and the cylindrical power Z Δ,i,target are taken into account.

[0007] It is found in DE 103 13 275 that it is advantageous not to express the target specifications as absolute values of the properties to be optimized, but as their deviation from the prescription, i.e. as the required local misadjustment. The advantage is that the target specifications are independent of the prescription (Sph V , Zyl V , Axis V , Pr V , B V ) and do not have to be changed for each individual prescription. Therefore, as "actual" values of the properties to be optimized, the absolute values of these optical properties are not taken into account in the objective function, but the deviation from the prescription. This has the advantage that the target values can be specified independently of the prescription and do not have to be changed for each individual prescription.

[0008] The respective power defects at the respective evaluation points are preferably taken into account together with weighting factors g i.SΔ and g i.ZΔ . Here, the target specifications of the power defects of the spherical power S Δ,i,target and / or the cylindrical power Z Δ,i,target , in particular together with the weighting factors g i.SΔ and g i.ZΔ , form a so-called spectacle lens design. Furthermore, further residuals can be taken into account, in particular further parameters to be optimized, such as coma and / or spherical aberration and / or prisms and / or magnification and / or distortion, inter alia, which are implicitly indicated in particular by the expression "+..." in the formula of the above-mentioned objective function F.

[0009] In certain cases, not only second-order aberrations (spherical, amplitude of astigmatism and cylinder axis) but also higher-order aberrations (e.g. coma, trefoil, spherical aberration) are taken into account, which in certain cases can contribute to a significant improvement, in particular in the individual adjustment of spectacle lenses.

[0010] It is known from the prior art to determine the wavefront shape of an optical element, in particular a spectacle lens bounded by at least two refractive boundary surfaces. This can be done, for example, by means of a numerical calculation of a sufficient number of adjacent rays and subsequent fitting of the wavefront data by means of Zernike polynomials. Another method is based on local wavefront tracking in refraction (cf. WO 2008 / 089999 Al). Here, only one single ray (the chief ray) is calculated for each view point, accompanied by the derivatives of the wavefront vertex depth as a function of the lateral coordinate (perpendicular to the chief ray). These derivatives can be formed up to a certain order, wherein the second derivative describes the local curvature properties of the wavefront (such as the refractive power, the astigmatism), and the higher derivatives are related to higher-order aberrations.

[0011] In the tracking of a ray through a spectacle lens, the local derivatives of the wavefront are calculated at suitable positions in the beam path in order to compare them with the desired values obtained from the refractive power of the spectacle lens wearer. The vertex sphere or the eye in the respective line of sight direction, for example the principal plane, is generally considered as the position for evaluating the wavefront. In this respect, it is assumed that a spherical wavefront emanates from the object point and propagates to the first spectacle lens surface. There, the wavefront is refracted and subsequently propagates to the second spectacle lens surface, where it is again refracted. The last propagation takes place from the second boundary surface to the vertex sphere (or the principal plane of the eye), where the wavefront is compared with the predetermined values for correcting the refractive power of the eye of the spectacle lens wearer.

[0012] For this comparison based on the determined refractive data of the respective eye, for the evaluation of the vertex sphere wavefront, an established model of an eye with visual impairment is assumed, in which a base eye with normal vision is overlaid with a visual impairment (refractive error). This has proven to be particularly successful, since no further knowledge of the anatomy or optics of the respective eye (e.g. distribution of the refractive power, eye length, refractive diopter and / or diopter diopter) is required. This is described, for example, in "Die Optik des Auges und der Sehhilfen" by Dr. Roland Enders, Springer-Verlag, Heidelberg, 1995, pages 25 ff. and in "Optische GmbH, Heidelberg, 1995, pages 25 ff. and in "Optische A detailed description of this model of spectacle lenses and refractive errors can be found in Diepes, Blendowske, "Optik und Technik der Brille", Springer- Verlag GmbH, Heidelberg, 2002, page 47 onwards. As a well-tried model, in particular the correction model according to REINER is used.

[0013] Here, a refractive error is considered to be a lack or excess of dioptres of the optical system of an eye with visual impairment compared to an eye of the same length with normal vision (residual eye). The dioptres of the refractive defect are in particular approximately equal to the distance point dioptres with a negative sign. In order to correct visual impairment completely, a spectacle lens and a refractive error are separated from the telescope system (afocal system). The residual eye (eye with visual impairment but without additional refractive defect) is considered to have normal vision. Therefore, if the image-side focus point of the spectacle lens coincides with the distance point of the eye with visual impairment and thus also with the object-side focus point of the refractive defect, the spectacle lens is said to correct the distance completely.

[0014] The document DE 102017007975 A1 or WO 2018 / 138140 A2, explicitly cited or whose content is fully included in the present specification, describes a method and a device allowing to improve the calculation or optimization of a spectacle lens, which very effectively adapts to the individual needs of the spectacle wearer by simple measurements of personal, optical and eye anatomy data.

[0015] Spectacle lenses are currently only offered for patients with an implanted intraocular lens (IOL), i.e. patients who have undergone a cataract operation (e.g. due to cataract), which are also used for patients with a natural eye lens. Therefore, there are currently no lenses that are specifically suitable for patients with an artificial lens. This means that the properties of the implanted artificial lens cannot be taken into account, which, however, differ greatly from the properties of a natural lens. For example, an IOL has a different spherical dioptre for at least partially compensating a corneal or length refractive error and / or has a different cylindrical dioptre for at least partially compensating a corneal astigmatism or at least partially neutralizing a lens astigmatism. In the case of conventionally optimized spectacle lenses, it is assumed that the spectacle lens has model-based properties, so that the eye model used for optimization in these cases can no longer correspond to the actual structure of an eye with an IOL, for example if the IOL at least partially compensates a length refractive error due to its dioptre (mean sphere). SUMMARY

[0016] It is an object of the present invention to improve the calculation or optimization of an ophthalmic lens, preferably of a progressive ophthalmic lens. In particular, it can be possible to provide a patient after cataract surgery with an ophthalmic lens specifically designed for the patient. In particular, it can be an object to improve the calculation or optimization of an ophthalmic lens, preferably of a progressive ophthalmic lens, with respect to a patient having an implanted intraocular lens. This object is in particular achieved by the computer-implemented method, the device, the computer program product, the storage medium and the corresponding ophthalmic lens having the features specified in the independent claims. Preferred embodiments are the subject of the dependent claims.

[0017] A first aspect for solving this object relates to a computer-implemented method for identifying relevant individual parameters of at least one eye of an ophthalmic lens wearer for calculating or optimizing an ophthalmic lens for the at least one eye of the ophthalmic lens wearer, wherein an intraocular lens is implanted in the at least one eye of the ophthalmic lens wearer as part of a surgery, the method comprising the steps of:

[0018] - providing individual refractive data of the at least one eye of the ophthalmic lens wearer;

[0019] - defining an individual eye model, wherein at least

[0020] - a shape and / or a refractive power of a cornea of the model eye, in particular a shape and / or a refractive power of a cornea anterior surface;

[0021] - a cornea to lens distance;

[0022] - parameters of a lens of the model eye;

[0023] - a lens to retina distance

[0024] - are defined as parameters of the individual eye model, wherein defining the parameters of the individual eye model is based on data for the vision correction of the at least one eye having the intraocular lens and further based on individual measurements and / or standard values of the eyes of the ophthalmic lens wearer and / or based on the provided individual refractive data, such that the model eye has the provided individual refractive data.

[0025] In a preferred embodiment, the data for the vision correction of the at least one eye having the intraocular lens comprise (in particular individual) intraocular lens data. Thus, in this embodiment, the parameters of the individual eye model are based on the intraocular lens data and further based on individual measurements and / or standard values of the eyes of the ophthalmic lens wearer and / or based on the provided individual refractive data, such that the model eye has the provided individual refractive data, and the parameters of the lens of the model eye are defined based on the intraocular lens data.

[0026] In a further preferred embodiment, the lens-to-retina distance of the eye of the spectacle wearer is identified and the parameters of the individual eye model are defined based on the identified lens-to-retina distance and further based on individual measurements and / or standard values of the eye of the spectacle wearer and / or based on the provided individual refraction data, such that the model eye has the provided individual refraction data and the lens-to-retina distance of the model eye is defined by the identified lens-to-retina distance of the eye of the spectacle wearer. In other words, in this embodiment, the data for the visual correction of the at least one eye with an intraocular lens comprises the identified lens-to-retina distance.

[0027] In particular, the data for the visual correction of the at least one eye with an intraocular lens can comprise the identified lens-to-retina distance and / or the intraocular lens data.

[0028] Thus, the present application in particular provides a computer-implemented method for identifying relevant individual parameters of at least one eye of a spectacle wearer for calculating or optimizing a spectacle lens for the at least one eye of the spectacle wearer, wherein an intraocular lens is implanted in the at least one eye of the spectacle wearer as part of a surgery or the at least one eye of the spectacle wearer has an implanted intraocular lens, in particular instead of or in addition to a natural lens, the method comprising the following steps:

[0029] - providing individual refraction data of the at least one eye of the spectacle wearer;

[0030] - defining an individual eye model, wherein at least

[0031] - the shape and / or the refractive power of the cornea of the model eye, in particular the shape and / or the refractive power of the corneal front surface;

[0032] - the cornea-to-lens distance;

[0033] - parameters of the lens of the model eye;

[0034] - the lens-to-retina distance;

[0035] are defined as parameters of the individual eye model, wherein:

[0036] a) the defining of the parameters of the individual eye model is performed based on the intraocular lens data and further based on individual measurements and / or standard values of the eye of the spectacle wearer and / or based on the provided individual refraction data, such that the model eye has the provided individual refraction data, wherein the parameters of the lens of the model eye are defined based on the intraocular lens data; and / or

[0037] b) identifying a lens-to-retina distance of the eye of the spectacle wearer and performing a parameter defining an individual eye model based on the identified lens-to-retina distance and further based on individual measurements and / or standard values of the eye of the spectacle wearer and / or based on provided individual refractive data, such that the model eye has the provided individual refractive data, wherein the lens-to-retina distance of the model eye is defined by the identified lens-to-retina distance of the eye of the spectacle wearer.

[0038] Thus, the method can comprise the procedure defined at point a) and the procedure defined at point b). The procedure defined at point a) is preferably performed if (in particular individual) intraocular lens data is known. Further preferably, the procedure defined at point b) is performed if no intraocular lens data is known. In other words, the procedure defined at point a) is performed in case of known intraocular lens data, while the procedure defined at point b) is performed in case of unknown intraocular lens data. However, in case of known intraocular lens data, it is also possible to perform the procedure described at point b) (e.g. to pre-empt inconsistencies and / or to only need to keep one algorithm or order channel available). In case of unknown intraocular lens data, it is also possible to perform the procedure defined at point a) by assuming certain intraocular lens data. In particular, the procedures defined at point a) and point b) represent (mutually independent) alternative procedures of the method.

[0039] As an alternative, the method can also only comprise the procedure defined at point a) or the procedure defined at point b). In the context of the procedure defined at point a), in particular, individual intraocular lens data is provided. The intraocular lens data can comprise or be known (e.g. measured or specified by the manufacturer) intraocular lens data. As an alternative or in addition, the intraocular lens data can comprise or be assumed to be intraocular lens data. In particular, the intraocular lens data is individual intraocular lens data.

[0040] The intraocular lens can in particular be an intraocular lens without lens or an intraocular lens with lens. The intraocular lens without lens replaces the natural lens, i.e. the at least one eye of the spectacle wearer only has the intraocular lens (and no longer the natural lens) after the operation. In contrast, the intraocular lens with lens is inserted or implanted into the at least one eye of the spectacle wearer in addition to the natural eye lens, i.e. the at least one eye of the spectacle wearer has both the intraocular lens and the natural eye lens after the operation.

[0041] In the context of the present invention, the term "lens of the model eye" can refer not only to a single real lens (e.g. a natural human eye lens or an artificial lens), but also to a lens system. The lens system can comprise one or more lenses, in particular two lenses (i.e. the natural lens of the eye and an artificial lens). In other words, in the context of the present invention, the "lens of the model eye" can be a lens, in particular a model-based lens or a virtual lens, which describes a natural eye lens or an (aphakic) artificial lens. As an alternative, in the context of the present invention, the "lens of the model eye" can also be a model-based lens system or a virtual lens system, in particular, which describes a natural eye lens and an additional (phakic) artificial lens. For example, the "lens of the model eye" can be understood as a thick lens of the model eye (or the "lens of the model eye" can be a thick lens of the model eye) which combines and / or describes both the properties of a natural eye lens and the properties of an additional artificial lens. In particular, in the context of the present invention, the term "lens of the model eye" is understood to mean "lens system of the model eye". Accordingly, in the context of the present invention, the term "lens-to-retina distance" is understood to mean, in particular, "lens system-to-retina distance". However, for the sake of simplicity, the terms "lens of the model eye" and "lens-to-retina distance" will be used only in the following.

[0042] The phakic artificial lens can for example be regarded as one own / individual or additional element in the eye model. As an alternative, the refractive power of the phakic artificial lens can influence the refractive power of the cornea (or one surface or both surfaces). In this case, the artificial lens can for example be an anterior chamber lens. As a further alternative, the refractive power of the phakic artificial lens can influence the refractive power of the natural eye lens (or the refractive power in one surface or both surfaces). In this case, the artificial lens can for example be a posterior chamber lens. If the artificial lens is introduced as an additional element, its properties, in particular the refractive power, the surface and / or the thickness, can be considered in the eye model as an additional parameter of the eye model. For example, the position of the additional lens can be defined as a known position or considered as an additional parameter in the eye model (e.g. a measured parameter or a model-based parameter). The defined position can for example (in the case of an anterior chamber lens) directly behind the cornea or at a specific distance behind the cornea or for example (in the case of a posterior chamber lens) directly in front of the eye lens or at a specific distance in front of the eye lens.

[0043] In particular, within the scope of the first aspect, a computer-implemented method for identifying relevant individual parameters of at least one eye of an eyewear wearer for the calculation or optimization of an ophthalmic lens for this at least one eye of the eyewear wearer is provided, the at least one eye of the eyewear wearer having an implanted intraocular lens, the method comprising the steps of:

[0044] - providing intraocular lens data about an intraocular lens implanted in an eye of an eyewear wearer;

[0045] - providing personal refraction data of the at least one eye of the eyewear wearer;

[0046] - defining an individual eye model, wherein in particular at least

[0047] - the shape and / or the refractive power of the cornea of the model eye, in particular the shape and / or the refractive power of the cornea anterior surface;

[0048] - the cornea-lens distance;

[0049] - parameters of the lens of the model eye;

[0050] - the lens-to-retina distance;

[0051] are defined based on the provided intraocular lens data and further based on individual measurements and / or standard values of the eye of the eyewear wearer and / or based on the provided individual refraction data, such that the model eye has the provided individual refraction data, wherein the defining of the parameters of the lens of the model eye is done based on the provided intraocular lens data. Preferably, at least the lens-to-retina distance is defined by calculation.

[0052] The spectacle lens can be optimized by tracing into the eye according to one of the methods described in WO2013 / 104548A1 or DE102017007974A1. As described in DE102017007975A1 or WO2018 / 138140A2, the eye model required for this is assigned individual values with known properties of the IOL, for example information from the manufacturer contained in the lens of the eye model. The IOL data includes data on the properties of the implanted IOL. These can be specified directly at the time of ordering or taken from a database by specifying the type or individual serial number. This is helpful or advantageous since the model-based values used in DE102017007975A1 or WO2018 / 138140A2 do not necessarily coincide with the properties of the actually implanted lens. This can be the case, for example, when the length myopia is at least partially compensated by an IOL with less diopter. In this case, the method described in DE102017007975A1 or WO2018 / 138140A2 would result in an eye length that is too short.

[0053] The eye model preferably includes various components such as cornea, lens, retina, etc. and parameters or a set of parameters of these components. The parameters of the eye model are, for example, the shape of the cornea anterior surface of the model eye, the cornea-lens distance, the parameters of the lens of the model eye, the lens-to-retina distance, etc.

[0054] In a preferred embodiment, the distance lens-to-retina (hereinafter referred to as DLR or d LR ) is determined from the defocus term of the entire eye, the defocus term of the cornea surface, the cornea-lens distance (hereinafter referred to as DCL or d CL ) and with respect to an IOL having one of the forms described in DE102017007975A1 or WO2018 / 138140A2. The term defocus term will be used in the following for the value of the diopter of an optical element or the symmetric second term (c 2,0 ) of the Zernike decomposition of a surface.

[0055] In particular, any one or more of the following data can be used:

[0056] - IOL data: This can be the defocus and the propagation length (thickness of the lens, hereinafter simply DLL) of the refractive surfaces (anterior and posterior surface) or the defocus of the diopter of the IOL. While a surface- and distance-based model can provide more accurate results in the optimization process, the optimization requires more calculation steps (refraction-propagation-refraction instead of just refraction) and the corresponding detailed information about the IOL can not be available.

[0057] - Defocus term for the entire eye: Here, the results of aberration measurements or autorefraction, subjective refraction or other determinations (e.g. retinoscopy) can be used. Alternatively, a so-called "optimized refraction" can be used, i.e. a calculation result from several components (e.g. subjective refraction and aberration measurements). Examples of such optimizations are compiled in DE 10 2017 007 975 A1 or WO 2018 / 138140 A2. In particular, the individual refractive data of at least one eye of the spectacle wearer include the defocus or defocus term of the (entire) eye.

[0058] - Corneal defocus term: can be taken, for example, from topography or topography measurements, or can be based on model assumptions.

[0059] - Cornea to lens distance: can be determined by measurement (eg, Scheimpflug imaging or OCT) or based on model assumptions.

[0060] Instead of or in addition to defocus, another variable may be used, preferably a second order term, such as the diopter in the main part with the highest or lowest diopter or in a meridian with a defined position (eg horizontal or vertical).

[0061] Upon request, the eye model can be supplemented with astigmatism (magnitude and axis, or other second-order variables according to the previous paragraph) and higher-order components of the entire eye and components (see DE 10 2017 007 975 A1 or WO 2018 / 138140 A2). These can be taken from, for example, IOL data, measured values ​​(e.g., topography / morphology or aberrations / autorefraction), model assumptions, and / or calculated values ​​(e.g., optimized refraction).

[0062] Typically, an IOL is provided with information about its asphericity or higher-order aberrations, which can be used when assigning higher-order aberrations to an eye model.

[0063] First, individual refractive data of at least one eye of the eyeglass wearer are provided. The individual refractive data are determined based on the individual refraction. The refractive data include at least the spherical and astigmatic visual impairments of the eye. In a preferred embodiment, the refractive data obtained also describe higher-order aberrations (HOA). Preferably, the refractive data (also called aberration data, in particular if they include higher-order aberrations) are measured by an optician, for example using an automatic refractometer or an aberrometer (objective refractive data). Alternatively or in addition, subjectively determined refraction can also be used. Subsequently, the refractive data will preferably be communicated to the lens manufacturer and / or provided to a calculation or optimization program. Thus, for the method according to the invention, the data can be accessible, in particular read out and / or received in digital form.

[0064] Preferably, providing individual refractive data comprises providing or identifying a vergence matrix S of a visual impairment of at least one eye.M Here, the vergence matrix describes the wavefront of the light emanating from or converging on a point on the retina in front of the eye. In terms of measurement technology, such refractive data can be determined, for example, by means of a laser illuminating a point on the retina of the spectacle wearer, from which point the light propagates. While the light from the illuminated point initially diverges substantially spherically in the vitreous body of the eye, the wavefront changes as it passes through the optical boundary surfaces of the eye, for example the lens and / or the cornea of the eye. The refractive data of the eye can thus be measured by measuring the wavefront in front of the eye.

[0065] Furthermore, the method according to the first aspect of the application comprises defining an individual eye model which individually defines at least certain specifications regarding the geometrical and optical properties of the model eye. Thus, in the individual eye model according to the application at least the shape (topography) and / or the refractive power of the anterior surface of the cornea, in particular of the cornea of the model eye, the cornea-lens distance d CL (also referred to as the anterior chamber depth between the cornea and the anterior surface of the lens of the model eye), the parameters of the lens of the model eye, in particular at least partially defining the refractive power of the lens of the model eye, and the lens-to-retina distance d LR (also referred to as the vitreous length between the lens, in particular the posterior surface of the lens, and the retina of the model eye), i.e. in such a way that the model eye has the provided individual refractive data, i.e. the wavefront emanating from a point on the retina of the model eye in the model eye matches the wavefront identified (e.g. measured or otherwise identified) for the spectacle wearer (up to the required accuracy). As parameters of the lens of the model eye (lens parameters), for example, geometrical parameters (shape of the lens surface and its distance) and preferably material parameters (e.g. refractive indices of the individual components of the model eye) can be defined so that in total they at least partially define the refractive power of the lens. As an alternative or in addition, parameters directly describing the refractive power of the lens of the model eye can also be defined as lens parameters. For the cornea, typically the shape of the anterior surface of the cornea is measured, but as an alternative or in addition, the refractive power of the cornea as a whole (without distinction between anterior and posterior surface) can be specified. It is also possible to specify the posterior surface of the cornea and / or the corneal thickness.

[0066] If individual intraocular lens data are known or provided, the parameters of the lens of the model eye can be defined (uniquely) on the basis of the provided intraocular lens data. In particular, the parameters of the lens of the model eye can correspond to the provided individual intraocular lens data. In other words, the provided intraocular lens data can be defined as the parameters of the lens of the model eye.

[0067] In the simplest case of an eye model, the refraction of the eye is determined by an optical system comprising the cornea's anterior surface, the eye lens and the retina. In this simple model, the refraction of the model eye is defined by the refraction at the cornea's anterior surface and the refractive power of the eye lens, preferably including spherical aberration and astigmatic aberration and higher order aberrations, and their position relative to the retina.

[0068] Here, the individual variables (parameters) of the model eye are defined accordingly based on the provided intraocular lens data and further based on individual measurements of the spectacle wearer's eye and / or based on standard values and / or / or based on provided individual refraction data. In particular, some parameters, such as the topography of the cornea's anterior surface and / or the anterior chamber depth and / or the curvature of at least the lens surface, etc., can be provided directly as individual measurements. Other values can also be taken from values of a standard model of the human eye, especially when the parameters concerned are very complex and cannot be measured individually. However, in general, not all (geometric) parameters of the model eye have to be specified from individual measurements or standard models. Rather, in the context of the present invention, the individual adaptation for one or more (free) parameters is performed by performing a calculation that takes the predefined parameters into account, so that the subsequently resulting model eye has the provided individual refraction data. Depending on the number of parameters contained in the provided individual refraction data, a corresponding number of (free) parameters of the eye model can be individually adjusted (fitted). Deviating from the proposed model, for example in WO 2013 / 104548 A1, at least the lens-to-retina distance can be defined in the context of the present invention by calculation.

[0069] For calculating or optimizing the spectacle lens, the first and second surfaces of the spectacle lens are in particular specified as starting surfaces with a predetermined (individual) position relative to the model eye. In a preferred embodiment, only one of the two surfaces is optimized. This is preferably the back surface of the spectacle lens. Both the front and back surfaces of the spectacle lens are preferably specified with a respective starting surface. However, in a preferred embodiment, only one surface is iteratively changed or optimized during the optimization process. For example, the other surface of the spectacle lens can be a simple sphere or a rotationally symmetric asphere. However, it is also possible to optimize both surfaces.

[0070] Starting from the two predetermined surfaces, the method for calculating or optimizing comprises determining a path of a chief ray through at least one view point (i) of at least one surface of the spectacle lens to be calculated or optimized into the model eye. The chief ray describes a geometric beam path emanating from one object point, passing through the two spectacle lens surfaces, the cornea's anterior surface and the lens of the model eye, preferably to the retina of the model eye.

[0071] Moreover, the method for calculating or optimizing according to this aspect of the application comprises evaluating the aberration of the wavefront resulting from a spherical wavefront incident on the first surface of the spectacle lens along the chief ray on the evaluation surface, in particular in front of or inside the model eye, in particular compared to the wavefront converging on a point of the retina of the model eye (reference light),

[0072] In particular, for this purpose a spherical wavefront (w0) incident on the first surface (front surface) of the spectacle lens along the chief ray is specified. This spherical wavefront describes the light (object light) emanating from the object point. When incident on the first surface of the spectacle lens, the curvature of the spherical wavefront corresponds to the inverse of the object distance. Therefore, the method preferably comprises specifying an object distance model which assigns an object distance to each viewing direction or each view point of at least one surface of the spectacle lens to be optimized. This preferably describes the individual wearing situation in which the spectacle lens to be manufactured will be used.

[0073] The wavefront incident on the spectacle lens is preferably refracted for the first time on the front surface of the spectacle lens. The wavefront then propagates from the front surface to the back surface along the chief ray within the spectacle lens, where it is refracted for the second time. Preferably, the wavefront now transmitted through the spectacle lens propagates along the chief ray to the cornea front surface of the eye, where it is preferably refracted again. Preferably, after further propagation within the eye to the lens of the eye, the wavefront is also refracted there again in order to finally preferably propagate to the retina of the eye. Each refraction process also causes a wavefront deformation depending on the optical properties of the individual optical elements (spectacle lens surface, cornea front surface, lens of the eye).

[0074] For the precise mapping of the object point onto the image point on the retina, the wave front has to leave the eye lens preferably as a converging spherical wave front, whose curvature corresponds exactly to the inverse value of the distance to the retina. (In the ideal case of a perfect image) the wave front emitted from the object point is compared to the wave front converging on a point on the retina (reference light), so that a mismatch can be assessed. This comparison and thus the assessment of the wave front of the object light in the individual eye model can be made at different points along the path of the chief ray, in particular between the second surface of the spectacle lens and the retina. In particular, the assessment surface can thus be located at different positions, in particular between the second surface of the spectacle lens and the retina. The refraction and propagation of the light emitted from the object point is calculated accordingly in the individual eye model, preferably for each viewing point. The assessment surface can be related to the actual light path or a virtual light path, such as for example in the case of the construction of the out-pupil AP. In the case of a virtual beam path, the light rays have to be propagated back through the posterior surface of the eye lens after refraction to the desired level, preferably to the level of the AP, wherein the refractive index used has to correspond to the medium of the vitreous body and not to the eye lens. If the assessment surface is arranged behind the lens or after refraction at the posterior surface of the lens of the model eye, or if the assessment surface is passed by the backward propagation along the virtual beam path as in the case of the AP, the final wave front of the object light can preferably simply be compared to the spherical wave front of the reference light. For this purpose, the method thus preferably comprises specifying a spherical wave front incident on the first surface of the spectacle lens, identifying a wave front caused at least by the refractive power of the first and second surfaces of the spectacle lens, the anterior surface of the cornea and the lens in the at least one eye of the model eye and assessing the resulting wave front from the spherical wave front converging on the retina.

[0075] If, however, the assessment surface is arranged between the lens within the lens or of the model eye and the spectacle lens to be calculated or to be optimized, the assessment surface is simulated as reference light by the backward propagation from the point on the retina through the individual components of the model eye upwards in order to compare the object light to the reference light there.

[0076] However, as already mentioned at the outset, a complete correction of the refraction of the eye is usually not possible for all viewing directions of the eye, i.e. for all viewing points of the at least one spectacle lens surface to be optimized. According to the viewing direction, an intentional misadjustment of the spectacle lens is thus preferably prescribed, which is in particular small in the main area of use of the spectacle lens, for example the central viewing points, and slightly higher in the less frequently used areas, for example the peripheral viewing points, depending on the application case. In principle, this procedure is known from the conventional optimization methods.

[0077] For optimizing an eyeglass lens, at least one surface of the eyeglass lens to be calculated or to be optimized is changed iteratively until the resulting wavefront aberration corresponds to a specified target aberration, i.e. in particular a specified value of the deviation of the wavefront of the reference light (e.g. a spherical wavefront with the center of curvature on the retina). The wavefront of the reference light is also referred to herein as the reference wavefront. Preferably, the method comprises minimizing a target function F, in particular a target function similar to the one described at the outset. Further preferred target functions will be described further below, in particular when higher order aberrations are taken into account. If the propagation of the object light to the retina is calculated, the evaluation can be carried out there instead of comparing wavefront parameters, for example by means of a so-called "point spread function".

[0078] In the context of the present application, it is therefore proposed, in particular for the calculation or optimization of an eyeglass lens, to define such an individual eye model which is defined as the vitreous length of the model eye as a function of other individual identifiers, in particular as a function of measured data of the eye, is calculated individually. This parameter does not have to be defined in advance, nor does it have to be measured directly. In the context of the present application, it is found that this leads to a significant improvement in the individual adaptation with relatively little effort, since the wavefront tracking results are very sensitive to this length parameter.

[0079] The individual calculation of the eye model, in particular the lens-to-retina distance (vitreous length), can already be carried out, for example, in an aberrometer or topographer with corresponding expansion functions. Preferably, the length of the eye is identified individually. It is particularly preferred to display the measured and / or calculated vitreous length and / or the identified (measured and / or calculated) eye length to the user. For this purpose, the corresponding device, in particular the aberrometer or topographer, has a corresponding display device.

[0080] In particular, in the context of the present application, as far as possible, the known properties of the implanted IOL can be used when calculating the eyeglass lens. This advantageously results in an eyeglass lens which is better suited to the patient with the implanted IOL and optimizes the imaging on the retina and the design retention.

[0081] In a preferred embodiment, the intraocular lens data comprises at least the defocus of the anterior surface of the intraocular lens, the defocus of the posterior surface of the intraocular lens and the thickness of the intraocular lens. Alternatively or additionally, the intraocular lens data comprises at least the defocus of the diopter of the intraocular lens or the power of the intraocular lens. Thus, the intraocular lens data can be the defocus of the dioptric surfaces (anterior and posterior surface) and the propagation length (thickness of the lens, hereinafter referred to as DLL) or the defocus of the IOL diopter. While a surface and distance based model can provide more accurate results in the optimization process, the optimization requires more calculation steps (refraction-propagation-refraction instead of just refraction) and the corresponding detailed information about the IOL can not be available. Alternatively or additionally, the intraocular lens data can comprise information, in particular a value, related to the so-called A-constant. The A-constant is an individual lens constant, in particular a correction factor that can occur in different named IOL calculation formulas. It is also known as IOL constant or "surgeon factor". Each IOL of each manufacturer has a different A-constant specified for each calculation formula. This constant represents the intraocular lens in various calculation formulas. Since all IOL constants can be converted into each other, there is in principle only one constant (number) to characterize a given intraocular lens over the entire available diopter range, independent of form factor, optical material, IOL diameter, etc. By using the A- or IOL-constant, the influence of individual surgical techniques, used measurements and surgical equipment and individual physiological differences in the patient cohort receiving the surgery on the IOL calculation is minimized. The A-constant reflects in particular any adaptations of the diopter and can be part of the lens prescription or the IOL prescription.

[0082] In a further preferred embodiment, the (individual) intraocular lens data is provided based on type or serial number information, in particular by the manufacturer of the IOL. This information can be indicated, for example directly at the time of ordering or retrieved from a database.

[0083] In a further preferred embodiment, the method further comprises the steps of:

[0084] - performing a consistency check on the defined eye model,

[0085] - resolving any inconsistencies, in particular by means of analytical and / or numerical and / or probabilistic methods.

[0086] In any case, the process according to the application provides a consistent model with respect to defocus (or other variables used to calculate the eye length). However, the consistency of the model is no longer guaranteed by other second order variables (e.g. the amplitude and the direction of the astigmatism). In other words, the eye model can be over-determined and thus no longer consistent. On the one hand, this can be due to inaccuracies in the manufacture of the IOL and in the measurements, which can occur for example in the measurement of the topography or topography, of the aberrations or autorefraction and / or of the anterior chamber depth. On the other hand, when using subjective refraction, inconsistencies can in principle arise if the subjective refraction or the optimized refraction does not correspond to the objective optical power of the entire eye. In the context of the present specification, a consistent eye model is understood to mean an eye model which represents the point on the retina at which the incident wavefront corresponding to the aberrations of the entire eye converges. This is synonymous with the fact that the wavefront emanating from the point of light on the retina corresponds to the aberrations of the entire eye after passing through the entire eye.

[0087] In particular, the consistency check can be carried out using a probabilistic approach. In this case, the consistency measure can be given as a probability. Any inconsistencies can be resolved, for example by determining the maximum of the probability.

[0088] For example, if a lens artificial lens, i.e. an artificial lens in addition to the existing natural lens, is implanted in the at least one eye of the spectacle wearer, resolving any inconsistencies can in particular include adjusting one or more parameters of the eye model (or postoperative eye model) which are modified or added due to the additional lens, if this helps or is necessary to achieve consistency of the eye model (or postoperative eye model).

[0089] Carrying out the consistency check and resolving any inconsistencies improves in particular the calculation or optimization of the spectacle lens for a patient with an IOL. However, it is also advantageous to carry out the consistency check and resolve any inconsistencies in the case of a spectacle lens which is not specifically intended for a patient with an IOL. Thus, the application generally provides a computer-implemented method for identifying relevant individual parameters of at least one eye of a spectacle wearer for calculating or optimizing a spectacle lens for the at least one eye of the spectacle wearer, comprising the following steps:

[0090] - providing individual refractive data of the at least one eye of the spectacle wearer;

[0091] - defining an individual eye model, wherein in particular one or more of the following information or parameters, i.e.

[0092] - the shape and / or the refractive power of the cornea of the model eye (12), in particular of the corneal front surface (18); and / or

[0093] - the cornea to lens distance; and / or

[0094] - parameters of the lens of the model eye; and / or

[0095] - the lens-to-retina distance; and / or

[0096] - the size of the entrance pupil; and / or

[0097] - the size and / or position of the physical aperture stop (or iris opening) is defined based on individual measurements and / or standard values of the eye of the eyeglasses wearer and / or based on provided individual refractive data,

[0098] - a consistency check of the defined eye model, in particular the provided individual refractive data, and optionally

[0099] - resolving any inconsistencies, in particular by means of analytical and / or numerical methods and / or probabilistic procedures or methods.

[0100] Since the entrance pupil represents the aperture stop of the cornea imaging, the position and size of the aperture stop of the eye can be converted to the position and size of the entrance pupil and vice versa, if the eye model comprises parameters of the cornea. In particular, if the position or size of the aperture stop or of the entrance pupil is used as (possibly additional) parameter of the eye model in this case, it can thus be sufficient.

[0101] “Defining an individual eye model” can mean to define the model parameters to specific values. However, as an alternative or in addition, “defining an individual eye model” can also comprise defining at least one consistency measure (or at least one probability). In particular, there can be multiple model parameter values. A consistency measure or probability can be defined for each combination of these values. For example, such a consistency measure or probability can be defined using a Bayesian approach.

[0102] Preferably, the definition of the lens-to-retina distance is performed at least by calculation. In the context of the present invention, the term “calculation” can comprise not only a calculation using equations, but also a selection of values based on statistical considerations or probabilities, performed in a statistical method, for example. For example, using a Bayesian approach, it is possible to select or define only the possible or the most likely lens-to-retina distance (which then still has to be resolved). Thus, in the context of the present invention, in particular, the term “calculation” can also comprise the selection of the possible or most likely value of one or more parameters and / or the definition of an optimization problem. In particular, the term “calculation” also comprises a selection, determination and / or definition in the context of a statistical procedure, for example in the context of or using a Bayesian approach. The term “calculation” can in particular also comprise an optimization.

[0103] In addition to performing consistency checks on a defined eye model and resolving any inconsistencies or as an alternative, the computer-implemented method can comprise defining or building a consistent eye model, in particular using a Bayesian approach and / or a maximum likelihood approach. In other words, the individual eye model used or to be defined is a consistent eye model, wherein consistency is made possible or established by statistical or probabilistic methods, in particular using a Bayesian approach and / or a maximum likelihood approach.

[0104] In particular, in this respect, a computer-implemented method and a corresponding device are provided for performing such a method to identify relevant individual parameters of at least one eye of a spectacle wearer for the calculation or optimization of a spectacle lens for at least one eye of a spectacle wearer, comprising one or more of the following steps or functions:

[0105] - providing individual refractive data of at least one eye of a spectacle wearer; and / or

[0106] - defining an individual eye model, wherein in particular one or more of the following information or parameters, i.e.

[0107] - the shape and / or power of the cornea of the model eye, in particular the shape and / or power of the corneal front surface; and / or

[0108] - the cornea to lens distance; and / or

[0109] - parameters of the lens of the model eye; and / or

[0110] - the lens to retina distance; and / or

[0111] - the size of the entrance pupil; and / or

[0112] - the size and / or position of the physical aperture stop (or iris opening) is defined in particular based on individual measurements and / or standard values of the eye of the spectacle wearer and / or based on the provided individual refractive data,

[0113] wherein one or more of the information or parameters and / or at least partly provided individual refractive data are initially defined in the form of a probability distribution, and wherein defining the individual eye model comprises identifying the parameters within the probability distribution defined by the probability approach or by identifying values of the information.

[0114] While in some aspects the model eye is first created by limiting the parameter values, so that the model eye can then be modified based on a consistency check using a probabilistic approach, so that the eye model is consistent, in the current case, instead of possibly for the parameter values of the inconsistency, a starting probability distribution for at least one parameter is used, so that the most likely parameter values are identified using a probabilistic approach, so that the most likely model eye is identified. The parameters of the probability distribution, e.g. mean value and / or standard deviation, can be based in particular on individual measurements and / or standard values of the eye of the spectacle wearer and / or on the provided individual refraction data. Further details and specific exemplary embodiments of such a method will be described below.

[0115] In the following, several examples will be used to describe how any inconsistencies in the eye model can be eliminated by means of an analytical calculation of the adjustment parameters.

[0116] The simplest possibility is to transfer the deviations to elements or components of the eye model (e.g. cornea, front surface of the IOL, back surface of the IOL, power of the IOL). For example, the back surface of the IOL can be chosen (contrary to the manufacturer's specifications) so that the model is consistent. For this (when using a defocus term), first the astigmatism, in particular according to the magnitude and direction (e.g. according to DE 10 2017 007 975 A1 or WO 2018 / 138140 A2) can be defined so that the eye model becomes consistent in terms of astigmatism after calculating the DLR. Furthermore, the higher-order components of this surface can be defined in a subsequent step (e.g. by means of the methods described in DE 10 2017 007 975 A1 or WO 2018 / 138140 A2), for example, so that the eye model is also consistent in these components. Alternatively or additionally, the corneal surface can be adjusted accordingly. This will be particularly useful if, due to the topography measurement, only the corneal information of the model or no information on astigmatism or higher-order components is available.

[0117] In a further preferred embodiment, any inconsistencies are resolved by adjusting or redefining one or more parameters of the eye model. Preferably, several parameters of the eye model are adapted and the adaptation is distributed to several parameters of the eye model. For example, the known deviations can be divided between several elements or components of the eye model and / or several parameters, e.g. cornea, front surface of the IOL, back surface of the IOL and / or power of the IOL. In the simplest case, a fixed or predetermined factor or proportion can be assumed, e.g. 33% on the cornea, 67% on the lens. Alternatively or additionally, a physiological-based distribution can also be used.

[0118] As an alternative or in addition, further or new parameters can be added to the eye model and defined such that the eye model becomes consistent. For example, the shape of the posterior surface of the cornea of the model eye can be such a further parameter. For example, in the case of a toric spectacle lens with a fixed astigmatism, the cylinder axis and / or the lateral decentration or tilt can be chosen so that the final astigmatism of the model eye conforms to the specification (as best as possible).

[0119] As an alternative or in addition, the lengths DCL, DLL and / or DLR can be adjusted. If necessary, the power of the entire eye can also be adjusted. Here, the target refraction of the spectacle lens can be changed accordingly in order to make the eye model consistent.

[0120] In a further preferred embodiment, the parameters of the eye model are determined with the aid of a probabilistic method, i.e. using probabilistic calculations. For this purpose, in particular, Bayesian statistics and / or maximum likelihood algorithms can be used.

[0121] As an alternative or in addition to the analytical calculation of the eye length based on a set of parameters, in particular all known parameters (hereinafter referred to as input parameters) can be combined and the parameters of the eye model (hereinafter referred to as output parameters) can be determined with the aid of statistical methods such as maximum likelihood and Bayesian. Here, one or more of the following information about at least one individual input parameter can be used:

[0122] - the confidence in the correctness;

[0123] - the measurement and manufacturing accuracy;

[0124] - the range of fluctuations in the collective or ensemble;

[0125] - the influence on the spectacle lens optimization.

[0126] In the following, a description of two such methods and specific examples will be given in the detailed description.

[0127] In a further preferred embodiment, an initial distribution of the parameters of the eye model and individual data about the characteristics of at least one eye are provided, the parameters of the individual eye model being determined based on the initial distribution of the parameters of the eye model and the individual data using probabilistic calculations. In other words, an initial eye model and individual data about the characteristics of at least one eye are provided, the parameters of the individual eye model being determined based on the initial eye model and the individual data using probabilistic calculations.

[0128] In a further preferred embodiment, the eye length of the model eye is determined taking into account the measured and / or calculated lens-to-retina distance. Preferably, the identified eye length is displayed on a display device or display.

[0129] The above method according to the application particularly relates to the properties or data of the implanted intraocular lens, i.e. the intraocular lens data are known. However, if this data is not known, or if individual intraocular lens data of the intraocular lens implanted in the at least one eye of the spectacle wearer cannot be provided, it is within the scope of the application to suggest identifying the lens-to-retina distance of the eye of the spectacle wearer, wherein the parameters defining the individual eye model are performed based on the identified lens-to-retina distance and further based on individual measurements and / or standard values of the eye of the spectacle wearer and / or based on the provided individual refraction data, such that the model eye has the provided individual refraction data, wherein the lens-to-retina distance of the model eye is defined by the identified lens-to-retina distance of the eye of the spectacle wearer. The provided individual refraction data about the at least one eye of the spectacle wearer are individual post-operative refraction data of the at least one eye of the spectacle wearer. The individual eye model is thus a post-operative eye model. This additional or alternative method according to the application, i.e. when the direct knowledge of the properties of the implanted lens is missing, the conclusion about the properties of the implanted IOL is drawn by measurements on the patient.

[0130] In particular, the subject accessory or alternative method, i.e. in case the properties or data of the implanted intraocular lens are not known, relates to a method for identifying relevant individual parameters of at least one eye of a spectacle wearer for the calculation or optimization of a spectacle lens for the at least one eye of the spectacle wearer, wherein an intraocular lens has been implanted as part of a surgery in the at least one eye of the spectacle wearer, the method comprising the following steps:

[0131] - providing individual post-operative refraction data of the at least one eye of the spectacle wearer;

[0132] - identifying the lens-to-retina distance (or eye length) of the eye of the spectacle wearer;

[0133] - defining an individual post-operative eye model, wherein in particular at least

[0134] - the shape and / or the refractive power of the cornea, in particular the shape and / or the refractive power of the corneal front surface, of the model eye of the post-operative eye model;

[0135] - the cornea-to-lens distance of the model eye of the post-operative eye model;

[0136] - the parameters of the lens of the model eye of the post-operative eye model;

[0137] - the lens-to-retina distance of the model eye of the post-operative eye model;

[0138] is defined based on the determined lens-to-retina distance (or eye length) and further based on individual measurements of the spectacle wearer's eye (determined preoperatively or postoperatively) and / or standard values and / or based on provided individual postoperative refractive data, such that the model eye of the postoperative eye model has the provided individual postoperative refractive data, wherein the lens-to-retina distance of the model eye of the postoperative eye model is defined by the lens-to-retina distance of the spectacle wearer's eye that has been identified.

[0139] The term operation (German: Operation) is generally abbreviated as OP. The term "post-OP" (German: Nach-OP) refers to the situation after the operation, while the term "pre-OP" (German: Vor-OP) refers to the situation before the operation. For example, the operation is a cataract operation, in which the natural eye lens is replaced by an artificial lens. However, it can also be an operation on an aphakic eye (an eye without a lens), in which an artificial lens is inserted or implanted into the patient's eye. Thus, the artificial lens can in particular denote a replacement for the natural eye lens. In particular, the natural lens of the wearer's eye has been replaced by an artificial lens during the operation. However, in addition to the natural eye lens, a man-made artificial lens can also be placed in at least one eye of the spectacle wearer. Thus, in addition to the natural lens of the eye, the term operation also includes the insertion or implantation of an artificial lens.

[0140] The spectacle lens is preferably optimized by tracking into the eye according to one of the methods described in WO 2013 / 104548 A1 or DE 102017007974 A1. By analogy with the description in DE 102017007975 A1 or WO 2018 / 138140 A2, the eye model required for this is assigned individual values. In this case, however, no information about the IOL is available, and the model-based values do not necessarily agree with the actually implanted lens. This can be the case, for example, if the length myopia is at least partially compensated by an artificial lens with less diopters. In this case, according to the procedure described in DE 102017007975 A1 or WO 2018 / 138140 A2, it will be assumed that the eye length is too short. Thus, based on data corresponding to the situation in which the original lens is located in the eye, the eye length or the lens-to-retina distance will be calculated as described in DE 102017007975 A1 or WO 2018 / 138140 A2.

[0141] Subsequently, other parameters (i.e. parameters of the eye lens, in this case an implanted intraocular lens) will be determined based on the thus calculated eye length (or calculated lens-to-retina distance) and the post-operative values of the overall eye aberration, the surface of the cornea and the cornea-to-lens distance, such that the dioptric power of this eye model corresponds to the overall eye aberration. This differs from the essence of the procedure in DE102017007975A1 or WO2018 / 138140A2 in that all values of the lens (in this case an implanted IOL) are determined, whereas the different second order terms (e.g. defocus) in DE102017007975A1 or WO2018 / 138140A2 are known. However, after determination of this term, further terms can be determined as described in DE102017007975A1 or WO2018 / 138140A2. These can be further second order terms, but also higher order terms (e.g. in further).

[0142] For the calculation of the eye length or the lens-to-retina distance, preferably the following data are specifically used:

[0143] - defocus of the overall eye before the replacement of the lens: this can be the result of an aberration measurement or autorefraction, subjective refraction or other determination (e.g. retinoscopy) before the surgical procedure. As an alternative, a so-called "optimized refraction" can be used, i.e. a calculated result from several components (e.g. subjective refraction and aberration measurement). Examples of such optimizations are compiled in DE102017007975A1 or WO2018 / 138140A2. Furthermore, the refractive power of the old glasses worn before the surgical procedure can be used;

[0144] - model-based values of the refractive power or the structure of the eye lens;

[0145] - measured or model-based values of the cornea-to-lens distance;

[0146] - measured or model-based values of the defocus of the cornea.

[0147] The data of the last two points can come from measurements before the surgical procedure (operation) or after the surgical procedure. The use of data determined after the surgical procedure is particularly useful if no corresponding measurements were made before the surgical procedure.

[0148] By analogy, the following data are preferably used for the calculation of the properties of the lens:

[0149] - the entire eye's aberrations after the replacement of the lens: these can be the result of an aberration measurement or autorefraction, subjective refraction or other determination (e.g. retinoscopy) after surgery. As an alternative, so-called "optimized refractions" can be used, i.e. a calculation from several components (e.g. subjective refraction and aberration measurement). Examples of such optimizations are compiled in DE 102017007975 A1 or WO 2018 / 138140 A2.

[0150] - a previously determined lens-to-retina distance;

[0151] - a measured or model-based value of the cornea-to-lens distance;

[0152] - a measured or model-based value of the corneal aberrations.

[0153] The data of the last two points can come from measurements before or after the surgical procedure (surgery). The use of data determined before the surgical procedure is particularly useful if no corresponding measurements are made after the surgical procedure.

[0154] Providing individual intraocular lens data can in particular comprise the following steps:

[0155] - determining the eye length based on data corresponding to the situation when the original natural lens was still in the eye of the spectacle wearer (situation before the implantation of the intraocular lens);

[0156] - calculating the individual intraocular lens data based on the identified eye length, the provided individual refractive data, the measured or model-based value of the cornea-to-lens distance and the measured or model-based value of the corneal aberrations.

[0157] The following examples include three scenarios. However, it should be understood that other combinations are also part of the present application.

[0158]

[0159] The lens-to-retina distance or the eye length of the eye of the spectacle wearer can be determined, for example, by direct measurement.

[0160] In a preferred embodiment, the method further comprises providing individual preoperative refractive data on at least one eye of the spectacle wearer, wherein the determination of the lens-to-retina distance or the eye length of the eye of the spectacle wearer is based on a correction of the individual preoperative eye model using the provided individual preoperative refractive data.

[0161] In a preferred embodiment, in the preoperative eye model, in particular at least

[0162] - the shape and / or the refractive power of the cornea, in particular of the corneal front surface, of the model eye of the preoperative eye model;

[0163] - the cornea-lens distance of the model eye of the pre-operative eye model;

[0164] - the model lens parameters of the pre-operative eye model; and

[0165] - the lens-to-retina distance of the model eye of the pre-operative eye model

[0166] are defined based on individual measurements of the spectacle wearer's eye (determined before or after surgery) and / or standard values and / or based on provided individual pre-operative refraction data, such that the model eye has the provided individual pre-operative refraction data, wherein at least the lens-to-retina distance is defined by a calculation correction.

[0167] The cornea anterior surface is preferably measured individually and the individual pre-operative eye model's lens parameters are calculated individually in order to meet the individually determined pre-operative refraction data. Here, in a preferred embodiment, the cornea anterior surface (or its curvature) is measured individually along the main portion (topography). In another preferred embodiment, the topography of the cornea anterior surface (i.e. the complete description of the surface) is measured individually. In another preferred embodiment, the cornea-lens distance is defined based on individual measurements of the cornea-lens distance.

[0168] It is particularly preferred that the lens parameters of the pre-operative model eye comprise the definition of the following parameters:

[0169] - the shape of the lens anterior surface;

[0170] - the lens thickness; and

[0171] - the shape of the lens posterior surface.

[0172] This more precise lens model can be used to further improve the individual adaptation, even though it is not necessary for the use of the present application.

[0173] In this case, in a particularly preferred embodiment, the lens thickness and the shape of the lens posterior surface are defined based on a predetermined value (standard value, e.g. from the technical literature) correction, wherein the definition of the shape surface of the lens front face further preferably comprises:

[0174] - providing a standard value for the average curvature of the lens anterior surface; and

[0175] - calculating the shape of the lens anterior surface while taking into account the provided individual refraction data.

[0176] In a further preferred embodiment of the more detailed lens model, the definition of the shape of the lens anterior surface comprises:

[0177] - providing individual measurements of the curvature in the normal section of the lens anterior surface.

[0178] In this case, it is particularly preferred that the lens thickness and the shape of the posterior lens surface are defined based on standard values, and even more preferably that the shape of the anterior lens surface is defined including:

[0179] - calculating the shape of the anterior lens surface taking into account the provided individual refractive data and the provided individual measurement of the curvature in the anterior lens surface normal section.

[0180] As an alternative or in addition to the lens or lens surface shape, defining the lens parameters can include defining the optical power of the lens. In particular, defining at least one position and the spherical power (or at least one focal length) of at least one principal plane of the lens of the model eye. The cylindrical power (magnitude and axial position) of the lens of the model eye is also particularly preferred. In another preferred embodiment, the optical higher-order aberrations of the lens of the model eye can also be identified.

[0181] Another independent aspect for solving this objective relates to a computer-implemented method for calculating or optimizing an eyeglass lens for at least one eye of an eyeglass wearer, comprising:

[0182] - a method for identifying relevant individual parameters of at least one eye of an eyeglass wearer according to the invention;

[0183] - specifying a first surface and a second surface for the eyeglass lens to be calculated or optimized;

[0184] - identifying the chief rays of at least one viewing point entering the model eye through at least one surface of the eyeglass lens to be calculated or optimized;

[0185] - evaluating the aberration of the wavefront resulting from a spherical wavefront incident on the first surface of the eyeglass lens along the chief rays on the evaluation surface compared to the wavefront converging on a point on the retina of the eye model;

[0186] - iteratively changing at least one surface of the eyeglass lens to be calculated or optimized until the evaluated aberration corresponds to a predetermined target aberration.

[0187] Another independent aspect for solving this objective relates to a computer-implemented method for calculating or optimizing an eyeglass lens for at least one eye of an eyeglass wearer, comprising:

[0188] - a method for identifying relevant individual parameters of at least one eye of an eyeglass wearer according to the invention;

[0189] - specifying a first surface and a second surface for the eyeglass lens to be calculated or optimized;

[0190] - identifying a chief ray of a light ray entering a model eye through at least one surface of an eyeglass lens for calculation or optimization;

[0191] - evaluating an aberration of a wave front caused by a spherical wave front incident on a first surface of an eyeglass lens along a chief ray on an evaluation surface compared to a wave front converging on a point on the retina of the model eye;

[0192] - iteratively changing at least one surface of an eyeglass lens to be calculated or optimized until the evaluated aberration corresponds to a predetermined target aberration.

[0193] Preferably, the evaluation surface is located between the cornea anterior surface and the retina. In a particularly preferred embodiment, the evaluation surface is located between the lens and the retina of the model eye. In another particularly preferred embodiment, the evaluation surface is located on the exit pupil (AP) of the model eye. Here, the exit pupil can be located in front of the posterior surface of the lens of the model eye. With this positioning, a particularly precise individual adaptation of the eyeglass lens can be achieved.

[0194] Another independent aspect which solves this object relates to a method for manufacturing an eyeglass lens, comprising:

[0195] - calculating or optimizing an eyeglass lens according to the eyeglass lens calculation or optimization method of the present invention; and

[0196] - manufacturing the eyeglass lens thus calculated or optimized.

[0197] Furthermore, the present invention provides a device for identifying relevant individual parameters of at least one eye of an eyeglass wearer for calculating or optimizing an eyeglass lens for the at least one eye of the eyeglass wearer, the device comprising:

[0198] - at least one data interface for providing individual data of characteristics of the at least one eye of the eyeglass wearer; and

[0199] - a modeling module for defining an individual eye model, in particular at least

[0200] - the shape and / or the optical power of the cornea, in particular the cornea anterior surface (18), of the model eye (12); and / or

[0201] - the cornea-lens distance;

[0202] - the model eye lens parameters;

[0203] - the lens-to-retina distance

[0204] based on individual measurements and / or standard values of the eyeglass wearer's eye and / or based on provided individual refraction data, wherein at least the lens-to-retina distance is determined by calculation; wherein

[0205] The modeling module is configured to perform a consistency check of the defined eye model using the provided individual refractive data and to resolve any inconsistencies, in particular with the help of analytical and / or probabilistic methods.

[0206] Another independent aspect that solves this object relates to a device for identifying relevant individual parameters of at least one eye of a spectacle wearer for calculating or optimizing an ophthalmic lens for at least one eye of a spectacle wearer, the at least one eye of the spectacle wearer having an implanted intraocular lens, comprising:

[0207] - at least one data interface for providing individual intraocular lens data about an intraocular lens implanted in an eye of the spectacle wearer and for providing individual refractive data about at least one eye of the spectacle wearer; and

[0208] - a modeling module for defining a single eye model, in particular at least

[0209] - a shape and / or optical power of the cornea, in particular of the cornea anterior surface (18) of the model eye;

[0210] - a cornea-lens distance;

[0211] - model lens parameters; and

[0212] - a lens-retina distance

[0213] as parameters of the individual eye model, wherein the parameters of the individual eye model are defined based on the vision correction data of the at least one eye with the intraocular lens based on the provided individual intraocular lens data and further based on individual measurements and / or standard values of the eye of the spectacle wearer and / or based on the provided individual refractive data, such that the model eye has the provided individual refractive data.

[0214] In a preferred embodiment, the parameters of the individual eye model are defined based on the intraocular lens data and further based on individual measurements and / or standard values of the eye of the spectacle wearer and / or based on the provided individual refractive data, such that the model eye (12) has the provided individual refractive data, wherein the parameters of the lens of the model eye are defined based on the intraocular lens data.

[0215] In a further preferred embodiment, the modeling module is configured to identify a lens-to-retina distance of the eye of the spectacle wearer. Furthermore, the parameters of the individual eye model are defined based on the identified lens-to-retina distance and further based on individual measurements and / or standard values of the eye of the spectacle wearer and / or based on the provided individual refraction data, such that the model eye has the provided individual refraction data, the lens-to-retina distance of the model eye being defined by the identified lens-to-retina distance of the eye of the spectacle wearer.

[0216] In particular, the present application provides a device for identifying relevant individual parameters of at least one eye of a spectacle wearer for calculating or optimizing a spectacle lens for the at least one eye of the spectacle wearer, the at least one eye of the spectacle wearer having an implanted intraocular lens, the device comprising:

[0217] at least one data interface for providing individual refraction data of the at least one eye of the spectacle wearer; and

[0218] a modeling module for defining an individual post-operative eye model, in particular at least

[0219] the shape and / or the refractive power of the cornea of the model eye, in particular the shape and / or the refractive power of the cornea anterior surface;

[0220] the cornea-lens distance;

[0221] lens parameters of the model eye;

[0222] the lens-to-retina distance

[0223] as parameters of the individual eye model, wherein:

[0224] a) the defining of the parameters of the individual eye model is performed based on the intraocular lens data and further based on individual measurements and / or standard values of the eye of the spectacle wearer and / or based on the provided individual refraction data, such that the model eye has the provided individual refraction data, wherein the parameters of the lens of the model eye are defined based on the intraocular lens data; and / or

[0225] b) the lens-to-retina distance of the eye of the spectacle wearer is identified by the modeling module and the defining of the parameters of the individual eye model is performed based on the identified lens-to-retina distance and further based on individual measurements and / or standard values of the eye of the spectacle wearer and / or based on the provided individual refraction data, such that the model eye has the provided individual refraction data, wherein the lens-to-retina distance of the model eye is defined by the identified lens-to-retina distance of the eye of the spectacle wearer.

[0226] The device or the modeling module can be configured to perform both process a) and process b). However, as an alternative, the device can also be configured to perform only the process defined under point a) or the process defined under point b). In the first case a), the data interface is in particular configured to provide the intraocular lens data in addition to the individual refractive data of the at least one eye of the spectacle wearer.

[0227] In particular, another independent method for solving this object relates to a device for identifying relevant individual parameters of at least one eye of a spectacle wearer for calculating or optimizing a spectacle lens for the at least one eye of the spectacle wearer, the at least one eye of the spectacle wearer having an implanted intraocular lens instead of a natural eye lens, comprising:

[0228] - at least one data interface for providing individual intraocular lens data about an intraocular lens implanted in the eye of the spectacle wearer and for providing individual refractive data about the at least one eye of the spectacle wearer;

[0229] - a modeling module for defining individual eye model, in particular at least

[0230] - the shape and / or the refractive power of the cornea of the model eye, in particular the shape and / or the refractive power of the corneal front surface;

[0231] - the cornea-to-lens distance;

[0232] - the lens parameters of the model eye;

[0233] - the lens-to-retina distance

[0234] said defining being based on the provided intraocular lens data and further based on individual measured values and / or standard values of the eye of the spectacle wearer and / or on the provided individual refractive data, such that the model eye has the provided individual refractive data, wherein the parameters of the lens of the model eye are defined based on the provided intraocular lens data. Preferably, the parameters of the lens of the model eye are defined by measurement and / or calculation.

[0235] Preferably, the modeling module is configured to identify the eye length of the model eye taking into account the measured and / or calculated lens-to-retina distance. The device preferably further comprises a display device for displaying the measured and / or calculated lens-to-retina distance and / or the determined eye length. The device is in particular preferably designed as an aberrometer and / or a topography.

[0236] Preferably, the modeling module is configured to perform a consistency check on the identified eye model, in particular the identified preoperative eye model and / or the identified postoperative eye model. Furthermore, the modeling module is preferably configured to resolve any inconsistencies, in particular by means of an analytical method and / or a probabilistic method (probabilistic calculation, e.g. using Bayesian statistics and / or a maximum likelihood method).

[0237] In particular, within the scope of the present application, there is provided a device for identifying relevant individual parameters of at least one eye of a spectacle wearer for calculating or optimizing an ophthalmic lens for the at least one eye of the spectacle wearer, an intraocular lens being implanted in the at least one eye of the spectacle wearer during surgery, wherein the device comprises:

[0238] - at least one data interface for providing personal postoperative refraction data of the at least one eye of the spectacle wearer;

[0239] - a modeling module for identifying a lens-to-retina distance of the eye of the spectacle wearer and for defining an individual postoperative eye model, in particular at least

[0240] - a shape and / or a refractive power of a cornea of the model eye of the postoperative eye model, in particular a shape and / or a refractive power of a cornea anterior surface;

[0241] - a cornea-to-lens distance of the model eye of the postoperative eye model;

[0242] - a lens parameter of the model eye of the postoperative eye model;

[0243] - a lens-to-retina distance of the model eye of the postoperative eye model

[0244] said defining being based on the determined lens-to-retina distance and further based on individual measurements (determined preoperatively or postoperatively) and / or standard values of the eye of the spectacle wearer and / or on the provided personal postoperative refraction data, such that the model eye of the postoperative eye model has the provided personal postoperative refraction data, wherein the lens-to-retina distance of the model eye of the postoperative eye model is defined by the identified lens-to-retina distance of the eye of the spectacle wearer.

[0245] Another independent aspect for solving this object relates to a device for calculating or optimizing an ophthalmic lens for at least one eye of a spectacle wearer, comprising:

[0246] - a device for identifying relevant individual parameters of at least one eye of a spectacle wearer according to the present application;

[0247] - a surface model database for specifying a first surface and a second surface of the ophthalmic lens to be calculated or optimized;

[0248] - a chief ray identification module for identifying a path of a chief ray entering into the model eye through at least one point of view of at least one surface of the spectacle lens for the calculation or optimization;

[0249] - an evaluation module for evaluating an aberration of the wavefront resulting from the spherical wavefront incident on the first surface of the spectacle lens along the chief ray on the evaluation surface compared to the wavefront converging on a point on the retina of the eye model; and

[0250] - an optimization module for iteratively changing the at least one surface of the spectacle lens to be calculated or optimized until the evaluated aberration corresponds to a predetermined target aberration.

[0251] Another independent aspect that solves this object relates to an apparatus for producing a spectacle lens, comprising:

[0252] - a calculation or optimization apparatus configured to calculate or optimize a spectacle lens according to the inventive method for calculating or optimizing a spectacle lens; and

[0253] - a machining apparatus configured to machine the spectacle lens according to the result of the calculation or optimization.

[0254] The apparatus for producing a spectacle lens can be designed as one piece or as a stand-alone machine, i.e. all components of the apparatus, in particular the calculation or optimization apparatus and the machining apparatus, can be part of one and the same system or one and the same machine. However, in a preferred embodiment, the apparatus for producing a spectacle lens is not designed as one piece but is realized by different, in particular stand-alone, systems or machines. For example, the calculation or optimization apparatus can be realized as a first system, in particular comprising a computer, and the machining apparatus can be realized as a second system, in particular a machine comprising a machining device. Here, the different systems can be located at different places, i.e. they can be locally separated from each other. For example, one or more systems can be located at a front end, while one or more other systems can be located at a back end. The individual systems can for example be located at different company sites or be operated by different companies. The individual systems in particular have a communication device in order to exchange data with each other, for example via a data product. Preferably, the individual systems of the apparatus can directly communicate with each other, in particular via a network, for example via a local network and / or via the internet. The above statements regarding the apparatus for producing a spectacle lens apply not only to this apparatus but generally to all apparatuses described in the context of the present invention. In particular, the apparatuses described here can be designed as a system. The system in particular can comprise a plurality of apparatuses, possibly locally separated, configured to perform the individual method steps of the respective method.

[0255] Moreover, the present application provides a computer program product or computer program article, in particular in the form of a storage medium or data stream containing program code designed to perform the method according to the present application for identifying relevant individual parameters of at least one eye of a spectacle wearer and / or performing the method according to the present application for calculating or optimizing an ophthalmic lens when loaded and executed on a computer. In particular, the computer program product is to be understood as a program stored on a data product. In particular, the program code is stored on the data product. In other words, the computer program product comprises computer-readable instructions which, when loaded into the memory of a computer and executed by the computer, cause the computer to perform the method according to the present application.

[0256] Moreover, the present application provides an ophthalmic lens produced by the method according to the present application and / or using the device according to the present application.

[0257] Moreover, the present application provides the use of an ophthalmic lens manufactured by the manufacturing method according to the present application, in particular in the predetermined average or individual wearing position of the ophthalmic lens in front of the particular eye of a spectacle wearer in the preferred embodiments. The spectacle wearer for correcting a visual impairment of the spectacle wearer.

[0258] The present application can in particular comprise one or more of the following aspects:

[0259] - ophthalmic lens as a product;

[0260] - calculation and manufacturing of an ophthalmic lens;

[0261] - calculation of properties of an ophthalmic lens (in particular design and surface);

[0262] - calculation of the eye length and assignment of an eye model

[0263] (also for purposes other than lens calculation);

[0264] - methods, devices and / or systems for acquiring relevant data, for example in the form of or as part of an ordering and / or industry software, in particular for manual input and / or import from measurement devices and / or databases;

[0265] - methods, devices and / or systems for transmitting relevant data, in particular protocols;

[0266] - methods, devices and / or systems for storing relevant data, which can be different from the methods, devices and / or systems for calculating an ophthalmic lens;

[0267] - methods, devices and / or systems for providing and retrieving IOL data, in particular based on the type or serial number information of an IOL manufacturer, an ophthalmic lens calculator or a third party;

[0268] - a device and a computer program product for implementing the above-mentioned points.

[0269] In particular, the computer-implemented method according to the application can be provided in the form of an ordering and / or industrial software. In particular, data required for the calculation and / or optimization and / or manufacturing of the spectacle lens, in particular the intraocular lens data and / or the prescription data and / or the individual refraction data (pre- and / or post-operative) can be acquired and / or transmitted the surgical refraction data of at least one eye of the spectacle wearer. The intraocular lens data can be transmitted, for example, from the manufacturer of the intraocular lens data to the calculator and / or the manufacturer of the spectacle lens. The prescription data and / or the individual refraction data can be transmitted, for example, from the optician and / or ophthalmologist or surgeon to the calculator and / or the spectacle lens manufacturer. Alternatively or additionally, the data can be retrieved from a database, in particular by means of the type and / or serial number of the implanted intraocular lens or by means of a patient code (e.g. customer or patient number, name, etc.). For example, the measurement or refraction data can also be called up directly from a measuring device. The data can be transmitted using a public transmission protocol or a transmission protocol specifically developed for the method according to the application. Alternatively or additionally, the data to be transmitted can also be entered at least partially manually by means of an input unit. In this way, the ophthalmologist or surgeon can transmit, for example, the so-called A-constant or IOL-constant of the intraocular lens used. In particular, the lens or IOL prescription can also be created semi-automatically or fully automatically on the basis of the transmitted data.

[0270] The device according to the application and / or the system according to the application, for example for ordering spectacle lenses, can in particular comprise a computer and / or a data server configured to communicate via a network, for example the Internet. The computer is in particular configured to execute a computer-implemented method, for example. The ordering software for ordering at least one spectacle lens, and / or the transmission software for transmitting the relevant data, in particular the intraocular lens data and / or the prescription data and / or the refraction data, and / or the identification software for identifying the relevant individual parameters of the at least one spectacle lens, according to the application, one eye of the spectacle wearer, and / or the calculation or optimization software for calculating and / or optimizing the spectacle lens to be produced.

[0271] The statements made above or below with regard to the embodiments of the first aspect also apply to the above-mentioned further independent aspects or methods, in particular the preferred embodiments thereof. In particular, the statements made above and below with regard to the embodiments of the respective other independent aspects also apply to the independent aspects of the application and the preferred embodiments thereof. BRIEF DESCRIPTION OF DRAWINGS

[0272] Preferred embodiments and examples of the application will be explained in the following at least partially with reference to the accompanying drawings, which show:

[0273] Figure 1 is a schematic diagram of a physiological and physical model of an eyeglass lens and an eye and of a light beam path in a predetermined wearing position;

[0274] Figure 2 is a P diagram for illustrating and explaining a method for determining parameters under constraints according to a preferred embodiment of the present application mess to S IOL and L 2,IOL an exemplary dependency diagram. DETAILED DESCRIPTION

[0275] Figure 1 is a schematic diagram of a physiological and physical model of an eyeglass lens and an eye and of an exemplary light beam path in a predetermined wearing position, a single eyeglass lens calculation or optimization according to a preferred embodiment of the present application is based on said exemplary light beam path.

[0276] Here, preferably only a single light ray (chief ray 10, which preferably passes through the eye rotation center Z') is calculated for each eye point of the eyeglass lens, and furthermore the derivative transversal coordinates (perpendicular to the chief ray) of the vertex depth of the wavefront are calculated according to the following formula. These derivatives are taken into account up to the order required, the second derivative describes the local curvature properties of the wavefront, higher derivatives are related to higher order aberrations.

[0277] When the light rays are traced through the eyeglass lens to the eye 12 according to a separately provided eye model, the local derivatives of the wavefront are finally identified at suitable positions in the light beam path in order to compare them there with a reference wavefront that converges on a point on the retina of the eye 12. In particular, the two wavefronts (i.e. the wavefront from the eyeglass lens and the reference wavefront) are compared with each other in an evaluation surface.

[0278] The "position" does not only mean a specific value of the z coordinate (in the direction of the light), but this coordinate value is combined with the specification of all surfaces through which the refraction takes place before reaching the evaluation surface. In a preferred embodiment, the refraction takes place through all refractive surfaces including the posterior surface of the lens. In this case, the reference wavefront is preferably a spherical wavefront whose center of curvature is located on the retina of the eye 12.

[0279] It is particularly preferred that no further propagation takes place after the last refraction, so that the radius of curvature of this reference wavefront corresponds to the distance between the posterior surface of the lens and the retina. In a further preferred embodiment, the propagation still takes place after the last refraction, preferably up to the exit pupil AP of the eye 12. This is the case, for example, at a distance of in front of the retina and thus even in front of the posterior surface of the lens, so that the propagation in this case is a back propagation (name The reference wavefront is also a sphere with the center of curvature on the retina in this case, but with a radius of curvature 1 / d AR .

[0280] For this, a spherical wavefront w0is assumed to emanate from the object point and to propagate to the first spectacle lens surface 14. There it is refracted, then it propagates to the second lens surface 16, where it is refracted again. The wavefront w g1 then propagates in the direction of the eye 12 along the chief ray (propagating wavefront w g2 ), until it hits the cornea 18, where it is refracted again (wavefront w c ). After further propagation within the anterior chamber of the eye to the eye lens 20, the wavefront is also refracted again by the eye lens 20, whereby, for example, on the posterior surface of the eye lens 20 or on the exit pupil of the eye the wavefront w e is compared with the spherical reference wavefront w s and the deviations in the target function for all viewing points are evaluated (preferably, respective weights are used for the individual viewing points).

[0281] Thus, the vision impairment is no longer described by a thin sphero-cylindrical lens as is customary in many conventional methods, but rather the corneal topography, the eye lens, the distances in the eye and the deformation of the wavefront in the eye are taken into account directly (including the low-order aberrations, i.e. sphere, cylinder and cylinder axis, and preferably also the high-order aberrations). Here, the vitreous length d LR is calculated separately in the eye model according to the application.

[0282] The aberrometer measurement preferably provides the individual wavefront deformation of the true eye with distance and near vision defects (aberrations, no absolute refractive power) and the individual mesopic and photopic pupil diameters. From the measurement of the corneal topography (surface measurement of the corneal front surface), the individual true corneal front surface is preferably obtained, which usually constitutes almost 75% of the total refractive power of the eye. In a preferred embodiment, the corneal back surface does not need to be measured. It is preferably described by an adaptation of the refractive index of the cornea rather than by a separate refractive surface, since the refractive index difference compared to the aqueous humor is very small and since the corneal thickness is very small.

[0283] In general, in this specification, bold lowercase letters are used to denote vectors, while bold uppercase letters are used to denote matrices, e.g. a (2x2) vergence matrix or a refractive index matrix

[0284]

[0285] And, italic such as d is used to denote a scalar.

[0286] Furthermore, bold, italic capital letters are used to denote wavefronts or surfaces as a whole. For example, S is the stigmatic matrix of the wavefront S, which includes the whole of the wavefront's higher order aberrations (HOA) in addition to the second order aberrations summarized in S. From a mathematical point of view, S represents the set of all parameters needed to describe the wavefront (with sufficient accuracy) in relation to a given coordinate system. Preferably, S represents a set of Zernike coefficients with pupil radius or a set of coefficients of a Taylor series. Particularly preferably, S represents a set of stigmatic matrices S for describing the second order wavefront characteristics and a set of Zernike coefficients (with pupil radius) for describing all remaining wavefront characteristics except the second order, or a set of coefficients according to a Taylor decomposition. Instead of a wavefront, similar statements apply to a surface.

[0287] The following data can in principle be measured directly, among others:

[0288] - wavefront S M , produced by a laser point on the retina and by the passage through the eye (from aberration measurement)

[0289] - shape of the corneal front surface C (by corneal topography)

[0290] - distance d between cornea and lens front surface CL (by thickness measurement). This variable can also be determined indirectly by measuring the distance between cornea and iris; if necessary, a correction value can be applied here. This correction can be the distance between the lens front surface and the iris from a known eye model (e.g. literature values).

[0291] - curvature of the lens front surface in the direction of L 1xx (by thickness measurement). In this case, without limiting the generality, the x-plane can be defined exemplarily such that this section lies within the x-plane. If the coordinate system is defined such that this plane is tilted, the derivative must be supplemented by a function of the corresponding angle. It is not required that this is the main section. For example, it can be a cross-section in the horizontal plane.

[0292] Furthermore, depending on the embodiment, the following data can be measured or taken from the literature:

[0293] - thickness d of the lens L

[0294] - curvature of the lens rear surface in the same direction as the lens front surface L 2,xx (by thickness measurement)

[0295] The lens rear surface thus has the following options:

[0296] - measurement of L 2,xx (L 2,M ) and the rotational symmetry L2,xx = L 2,yy = L2 = L 2,M and L 2,xy = L 2,yx = 0

[0297] Take L 2,Lit from literature (L 2,xx ) and rotate symmetrically L 2,xx = L 2,yy = L2 = L 2,M and L 2,xy = L 2,yx = 0

[0298] Take the complete (asymmetric) form L2 2,Lit from literature (L

[0299] L 2,xx (L 2,M ) is measured and the assumption of a cylinder or from literature L 2,xx = L 2,M and L 2,xy = L 2,yx = f(L 2,xx , a Lit ) and L 2,yy = g(L 2,xx , a Lit ) other specified asymmetric a Lit

[0300] The following data can be found in literature:

[0301] The refractive indices n CL of the cornea and the anterior chamber of the eye and n LR of the aqueous humor and n L of the lens

[0302] This especially the distance d LR between the posterior surface of the lens and the retina and the components L 1,yy and L 1,xy = L 1,yx of the anterior surface of the lens are unknown parameters. To simplify the form, the distance d LR can also be written as the vergence matrix D LR = D LR • 1, where D LR = n LR / d LR . Furthermore, the variable τ is usually used, which is defined as τ = d / n (where for the refractive indices, the respective refractive index must always be used as n, for d and τ, for example τ LR = d LR / n LR , τ CL = dCL / n CL ).

[0303] The modeling of the passage of the wavefront through the eye model used according to the invention, i.e. after passing through the surfaces of the spectacle lens, can be described as follows in a preferred embodiment, where the lens is described via the front and back surfaces, with the vergence matrix explicitly specified by the transformation:

[0304] 1. The wavefront S with the vergence matrix S is refracted on the cornea C with the surface refractive matrix C to the wavefront S with the vergence matrix S′ C =S+C wavefront S′ C

[0305] 2. Around the depth of the anterior chamber d CL (the distance between the cornea and the anterior surface of the lens) to the vergence matrix S L1 =S′ C / (1-τ CL ·S′) of the wavefront S L1 Spread

[0306]

[0307] 3. Refracted on the front surface L1 of the lens with surface refractive power matrix L1 to the lens with vergence matrix S′ L1 =S L1 +L1 wavefront S′ L1

[0308] 4. Thickness of the lens d L To have a gathering and dispersing matrix S L2 =S′ L1 / (1-τ L ·S′ L1 ) of the wavefront S L2 Spread

[0309] 5. Refracting on the back surface L2 of the lens with the surface refractive power matrix L2 to the lens with the convergence matrix S' L2 =S L2 +L2 wavefront S′ L2

[0310] 6. The distance d between the lens and the retina LR To have a gathering and dispersing matrix S R =S′ L2 / (1-τ LR ·S′ L2 ) of the wavefront S R Spread

[0311] Propagation distance τ CL , τ CL and τCL 2. Each of the steps 4, 6 can be divided into two parts 2a,b), 4a,b) or 6a,b) according to the following schemes, where step 6a,b) is explicitly read:

[0312] 6a. Propagation around the distance between the lens and the intermediate plane to a wave front S with a vergence matrix S = S LR

[0313] 6b. Propagation around the distance between the intermediate plane and the retina to a wave front S with a vergence matrix S = S R

[0314] Here, and can be positive or negative, so that it should always hold and In any case, steps 6a and 6b can be combined again by S = S However, the division in steps 6a and 6b provides advantages and the intermediate plane can preferably be placed in the plane of the exit pupil AP, which is preferably located in front of the posterior surface of the lens. In this case, and

[0315] The division of steps 2, 4 can be similar to the division of step 6 in 6a,b).

[0316] The decisive factor for the evaluation surface of the wave front is not only the absolute position with respect to the z-coordinate (in the direction of the light) but also depends on the number of surfaces on which refraction takes place until the evaluation surface. Thus, the same level can be passed several times. For example, the plane of the AP (usually located between the anterior surface of the lens and the posterior surface of the lens) is first formally passed through by the light after the hypothetical step 4a, where the propagation length to this plane occurs from the anterior surface of the lens. This plane is passed through for the second time after step 6a, when, after refraction at the posterior surface of the lens, the propagation back to the AP plane, i.e. is synonymous with S = S In the case of a wave front S AP mentioned in the text, the wave front S AP = S LR is always meant which should preferably be the result of step 6a (unless explicitly stated otherwise).

[0317] These steps 1 to 6 will be referred to again in the further course of the description. They describe the preferred relationship between the vergence matrix S of the corneal wave front S and the vergence matrix of all intermediate wave fronts resulting therefrom at the refractive intermediate surface of the eye, in particular the wave front S'L2 the vergence matrix S' L2 ( even the wavefront S on the retina R ). These relationships can be used both to calculate a priori unknown parameters (e.g. d LR or L1), thus assigning values to the model individually or generally, and to simulate the propagation of the wavefront in the eye for the optimization of the spectacle lens with the model of the acceptance task.

[0318] In the preferred embodiment, the surfaces and wavefronts are treated to the second order, for which the representation by means of the vergence matrix is sufficient. Another preferred embodiment described later takes into account and also uses aberrations of higher order.

[0319] In the second order description, the eye model has, in the preferred embodiment, twelve parameters as degrees of freedom of the model which must be assigned values. These preferences include three degrees of freedom of the surface power matrix C of the cornea C, three degrees of freedom of the surface power matrices L1 and L2 of the front and back surfaces of the lens, and the length parameters anterior chamber depth d CL , lens thickness d L and vitreous length d LR , each corresponding to one degree of freedom, respectively.

[0320] In principle, these parameters can be assigned values in several ways:

[0321] i. directly, i.e. individual measurement of the parameters

[0322] ii. a priori given parameter values, for example as literature values or from estimates, for example due to the presence of a measured value of another variable which is related in a known manner to the parameter determined on the basis of a previous population analysis

[0323] iii. from a consistency condition, for example compatibility with a known refraction

[0324] The total number of second order degrees of freedom df2 (df stands for ‘degrees of freedom’, the index ‘2’ stands for second order) of the eye model thus consists of

[0325] df2 = df2(i) + df2(ii) + df2(iii)

[0326] For example, if there are direct measurements of all twelve model parameters, then df2(i) = 12, df2(ii) = 0 and df2(iii) = 0, which will be denoted in the following by the notation df s = 12 + 0 + 0, for simplicity. In this case, the objective refraction of the relevant eye is also defined, so that no further objective refraction determination needs to be carried out.

[0327] The central aspect of the present invention exactly relates to the purpose of not having to measure all parameters directly. In particular, measuring the refractive power of the relevant eye or determining it objectively and / or subjectively is much easier than measuring all parameters of the model eye separately. Preferably, there is thus at least one refraction, i.e. the wavefront S M of the eye, whose measurement data up to the second order correspond to the data on the vergence matrix S M . If the eye model is to be assigned according to purely objective measurement data, these values can be taken from an aberrometry measurement or an autorefractometry measurement, or are assigned according to (ii) together with other given data. The consideration of subjective methods, i.e. subjective refraction, will be described later, which can be an alternative to the objective measurement as refraction, or by combining both results. The three conditions in accordance with the three independent parameters of the vergence matrix S M thus make it possible to derive three parameters of the eye model, which correspond to df2(iii) = 3 in the above-mentioned notation.

[0328] Thus, in the case where not all model parameters can be measured directly or these measurements are very complex, the present invention makes use of the possibility of distributing the missing parameters in a useful way. For example, if direct measurement values (df2(i) < 9) are available for up to nine model parameters, the refraction condition can be used to calculate three model parameters (df2(iii) = 3). If exactly df2(i) = 9, then all twelve model parameters are uniquely determined by measurement and calculation, and remain (df2(ii) = 0). If, on the other hand, df2(i) < 9, then df2(ii) = 9 - df2(i) > 0, i.e. the model is underdetermined in the sense that the df2(ii) parameters must be defined a priori.

[0329] By providing a separate refraction, i.e. the measurement data on the wavefront S M of the eye, in particular up to the second order, the necessary data on the vergence matrix S M are accordingly available. According to the conventional method described in WO 2013 / 104548 A1, in particular, the parameters {C, d CL , S M} are measured. In contrast, the two length parameters d L and d LR (or D LR ) are usually defined a priori (for example, by literature values or estimates). In WO 2013 / 104548 A1, in particular, a distinction is made between two cases, in which L2 is defined a priori and L1 is calculated therefrom, or vice versa. The above-mentioned publication discloses equations (4) and (5) as calculation rules. For both cases, df2 = 4 + 5 + 3 remains.

[0330] Among the terms used in steps 1 to 6 above, L1 is adapted to measure, in particular by means of the matrix C calculated from the same measurements by steps 1, 2 M and propagating it to the object side of the anterior lens surface. On the other hand, by means of the reverse execution of 6, 5, 4, the spherical wave is calculated from the imaginary point-like light source on the retina front to back by means of the surface power matrix L2 defined on the posterior lens surface before and by means of the wave front obtained at that time from the posterior lens surface to the image side of the anterior lens surface. Since in the aberrometry measurement the measured wave front comes from the wave front emitted from the point pm on the retina and thus, due to the reversibility of the beam path, is identical to the incident wave front converging on this point on the retina (S = S M ), the difference of the thus determined vergence matrices S L1 and S' L1 must be obtained by means of the matrix L1. This obtains equation (4) in the mentioned publication:

[0331]

[0332] Another case in the cited publication involves the adjustment of the matrix L2 to the measured values after the matrix L1 has been defined. The only difference now is that the measured wave front S M goes through steps 1, 2, 3, 4 and the hypothetical wave front only up to step 6 from the point-like light source, and what is to be done to adapt to the lack of the posterior lens surface L2 is now 5, according to equation (5) of the above publication:

[0333]

[0334] The central idea of the present invention is to calculate at least the length parameter d LR (or D LR ) from other measurement data and prior assumptions about other degrees of freedom instead of assuming the prior itself as conventionally. In the context of the present invention, it has turned out that this leads to a significant improvement of the individual adaptation with relatively little effort since the wave front tracking results prove to be very sensitive to this length parameter. This means that it is advantageous according to the present invention if at least the length parameter d LR belongs to the calculated df2(iii) = 3 parameters. In particular, this parameter is difficult to measure directly, it varies comparatively large between different test subjects and these variations have a comparatively large influence on the imaging of the eye.

[0335] The vergence matrix S MThe data on C and particularly preferably the data on C are preferably obtainable from individual measurements. In a further preferred aspect, also preferred in the following embodiments, in the assumption regarding the data on the posterior surface of the lens, a spherical posterior surface, i.e. a posterior surface without astigmatism component, is taken as a basis.

[0336] In a preferred embodiment of the application, second-order measurement data of the cornea C are available, which correspond to the data on the surface refractive power matrix C. While these values can be obtained from topography measurements, the latter are not necessary. In contrast, topography measurements are sufficient. This case corresponds to the case df2=3+6+3, in particular the anterior chamber depth d CL is one of the six parameters to be defined a priori.

[0337] If no individual measurements are made, the case is df2=3+6+3. In order to be able to uniquely determine d LR , the six parameters from {L1, L2, d L , d CL} must be assigned by assumptions or literature values. In addition to d LR , two further calculation results. In a preferred embodiment, the parameters of the posterior surface of the lens, the mean curvature of the anterior surface of the lens and the two length parameters d L and d CL are subjected to an a priori assignment (as predetermined standard values).

[0338] In a case that is particularly important for the application, the anterior chamber depth d CL , i.e. the distance between cornea and anterior surface of the lens, is also known, for example from pachymeter or OCT measurements. The measurement parameters thus include {C, d CL , S M}. This case corresponds to the case df2=4+5+3. The problem is thus mathematically still not determined, so that five parameters from {L1, L2, d L} must be a priori eliminated by assumptions or literature values. In a preferred embodiment, these are the parameters of the posterior surface of the lens, the mean curvature of the anterior surface of the lens and the lens thickness.

[0339] In terms of the accuracy of the individual adaptation alone, it is advantageous to be able to assign individual measurements to as many parameters as possible. In a preferred embodiment, the lens curvature is additionally provided in the normal section on the basis of individual measurements. This will lead to the case df2=5+4+3, and it is sufficient to a priori define four parameters from {L 1yy , a L1 , l 2, d L}. Here, in a preferred embodiment, parameters of the posterior surface of the lens and the lens thickness are also involved. The specific calculations will be described below.

[0340] In particular, as an alternative to the normal section of the anterior surface of the lens and in addition to the anterior chamber depth, the lens thickness can also be obtained from individual measurements. This eliminates the need to allocate model data or estimate parameters for this parameter (df2 = 5 + 4 + 3). Otherwise, what has already been said above applies. This embodiment is particularly advantageous if a pachymeter is used, the measurement depth of which allows the posterior surface of the lens to be identified, but not the lens curvature to be determined sufficiently reliably.

[0341] In addition to the anterior chamber depth and the normal section of the anterior surface of the lens, one (e.g. a measurement in two normal sections) or two further parameters (measurement of the main portion and the axial position) of the anterior surface of the lens can also be obtained by individual measurements. In particular, this additional information can be utilized in two ways:

[0342] Abandoning prior assumptions: One or both of the assumptions that are otherwise made a priori can be abandoned and determined by calculation. In this case, the cases df2 = 6 + 3 + 3 and df1 = 7 + 2 + 3 arise. In the first case, the average curvature of the posterior surface can be determined (assuming a posterior surface without astigmatism), while in the second case the surface astigmatism (including the cylindrical axis) of a surface with a given average curvature can be determined. As an alternative, the lens thickness can also be determined from the measured values in both cases.

[0343] However, such a procedure generally requires a certain degree of caution, since noisy measurement data can easily cause the published parameters to "run away". The model can thus become worse rather than better overall. One possibility to prevent this is to specify anatomically reasonable limits for these parameters and to limit the variation of the parameters within this range. Of course, these limits can also be specified as a function of the measured values.

[0344] Reducing measurement uncertainty: On the other hand, if the same prior assumptions are made (preferably, {L2, d L}), the cases df2 = 6 + 4 + 3 and df2 = 7 + 4 + 3 exist, so the system is mathematically overdetermined.

[0345] Instead of determining D LR according to the following explanation, D LR is determined ("fitted") such that the distance between L1 resulting from the equation and the measured L1 (or L1 supplemented by the missing parameter) becomes minimal. Obviously, a reduction in measurement uncertainty can be achieved by this procedure.

[0346] In a further preferred embodiment, the anterior chamber depth, two or three parameters of the anterior lens surface and the lens thickness are measured separately. The calculation of the other variables is done in the same way, whereby the prior assumptions on the lens thickness can be replaced by the corresponding measured values.

[0347] In a further preferred embodiment, separate measurements of the anterior chamber depth, at least one parameter of the anterior lens surface, the lens thickness and at least one parameter of the posterior lens surface are provided. This is a supplement to the above cases. The corresponding additional measured parameters can be performed in analogy to the stepwise extension of the above sections. These cases are particularly advantageous if the above mentioned thickness measuring units, which measure in one plane, two planes or over the entire surface, are extended accordingly in the measurement depth and are precise enough to identify the curvature data sufficiently accurately.

[0348] If the above already mentioned formula (1 b) is directed to D LR is solved in order to calculate the posterior lens surface for a given eye length (where D LR = n LR / d LR is the inverse vitreous length d LR multiplied by the refractive index n LR ), i.e.

[0349]

[0350] which results in:

[0351]

[0352] for calculating D LR . Since D LR is a scalar, all quantities used for the calculation must also be considered as scalars. Preferably, S M , C, L1 and L2 are each the spherical equivalent of the visual impairment, the cornea, the anterior lens surface and the posterior lens surface, respectively. When the vitreous length d LR (therefore the eye length is d A = d C + d CL + d L + d LR ) is calculated, one of the surfaces, preferably the anterior lens surface L1, can be modified again with respect to the cylinder and the HOA in order to adapt it consistently.

[0353] For the calculation, for the lens surface diopters, the values of the so-called Bennett & Rabbetts eye can be used, which can be taken from, for example, the book "Bennett & Rabbets' Clinical Visual Optics" by Ronald B. Rabbetts, Butterworth- Heinemann, 1998, ISBN-10: 0750618175, Table 12.1 of the third edition. The results of the calculations described above are in very good agreement with population statistics, which show that myopic vision disorders tend to result in large eye lengths and vice versa (see, for example, C. W. Oyster: "The Human Eye" of 1998). However, the described calculations are even more precise, since the direct use of the correlation from the population statistics leads to non-physical values of the eye lens, which is avoided by the method according to the application. The precise knowledge of the lens parameters is more important for the method which assumes given these parameters. For example, if the consumer has a vision disorder of -10 dpt before his cataract surgery, his eye length must be between 28 mm and 30 mm. However, after the surgery, due to his emmetropia, the derived eye length is 24 mm, which does not correspond to the actual eye length.

[0354] In the following, preferred embodiments of the application will be explained.

[0355] Example of the use of Bayesian statistics

[0356] The aim of the method using Bayesian statistics is, if possible, to use all available sources of information about an eye or a pair of eyes in a consistent manner to achieve the best correction of the eye or to have a spectacle lens, for example a spectacle lens, according to these information.

[0357] Usually, this information is incomplete and / or imprecise, which has so far often led to the fact that only simplified eye models are used to calculate the lenses for the eye. Such simplified eye models are, for example, eyes characterized only in terms of diopters, since this can be determined with a certain accuracy (for example, spherical equivalent error of ± 0.75 dpt). However, if it is desired to use more complex eye models for the calculation of the eye lenses, it makes sense to include information about the eye length as well as the position and curvature of the refractive surfaces of the cornea and the eye lens in the calculation, but this should only be considered as much as possible within its range of accuracy.

[0358] In Bayesian statistics (see D S Sivia: "Data Analysis - A Bayesian Tutorial", Oxford University Press, 2006, ISBN-13: 978-0198568322 or ET Jaynes: "Probability Theory", Cambridge University Press, 2003, ISBN-13: 978-0521592710), information is always described in the form of a probability distribution (in the case of continuous parameters, it is the probability density).

[0359] In this sense, a probability or probability density can be assigned to an individual eye model with a given set of parameters. An individual eye model that is consistent with the available information (e.g. objective wavefront measurements and the eye's biometric features) has a higher probability or probability density, because, for example, the propagation and refraction of the wavefront produced by a point light source after the eye on the retina reproduces the measurement data well within the measurement accuracy of the objective wavefront measurements, likewise the parameters of the individual eye match the available information on eye biometrics from the literature within the known distribution range. Individual eye models that are not consistent with the available information are assigned a low probability or probability density accordingly. The probability or probability density of an individual eye model can be written as

[0360] prob(θ i |d i ,I)

[0361] where θ i denotes the parameters of the individual eye model i, d i is the measurement data (e.g. it can include the current refraction or the refractive power measured before the ophthalmic procedure, the measured corneal shape and / or refractive properties, the measured length of the eye on the individual eye or other variables). Using I, the current state of knowledge after evaluating the data, i.e. the existing background information (e.g. about the measurement process of the refractive power, the parameter distribution of the individual eye model or other relevant variables in the population) is summarized. The vertical line "I" indicates that the "I" variable distribution is on the left side of the "I" and the given (i.e. fixed) variable on the right side of the "I".

[0362] The information obtained during the measurement process, in which the measurement data d i , can also be understood as the data d i under the given parameters θ i of the individual eye model i.

[0363] prob(d i | θ i ,I)

[0364] The accuracy of the measurement process is reflected in the width of the distribution: an accurate measurement has a narrower distribution than an inaccurate measurement, the latter having a wider or wider data distribution d i .

[0365] Now, if one wishes to calculate the distribution of parameters of an individual eye using the given data and background information, one can use the following proportion:

[0366] prob(0 i |d i ,I)∝prob(0 i |I)prob(d i |0 i ,I)

[0367] The term prob(0 i I) describes the background knowledge about the parameters of the individual eye model. This can be information from the literature, for example, or information from past measurement data. This can be data from the same person for whom the lens is being manufactured, or data from measurements made for a large number of other people.

[0368] The probabilities here are used as a measure of consistency. In particular, in the case where both prob(0 i I) and prob(d i |0 i , I) are high, one can find parameter values for the individual eye model that are consistent with the measurement results.

[0369] The probability or probability density prob(0 i |d i , I) can also be normalized appropriately so that the proportion can be written as an equation.

[0370] The term prob(0 i |d i , I) can also include parameters of the eye lens. For example, some parameters 0 i may include the refractive power of the eye lens, its position and / or orientation in the eye, or other variables such as the refractive index and curvature or shape of the surface.

[0371] The eye lens can be a natural lens. In this case, one can use literature data about the parameters of natural human eye lenses (e.g. curvature distribution of the anterior and / or posterior surface, refractive index, etc.).

[0372] If the eye lens is an artificial lens, one must not use the parameter distribution of a natural eye lens. Instead, one should use the parameters of the artificial lens, if they are known individually. Otherwise, one can use a distribution of these parameters from literature studies of eyes that have undergone the surgery. If such information is not available, one can choose a flat distribution within a reasonable range. For parameters that are positive definite and define a length scale (e.g. radius of curvature or distance), one can also choose a distribution that is flat in the logarithm of these parameters.

[0373] Formally, the situation of "natural eye lens" or "artificial lens as eye lens" will be described by different states of background knowledge I (ie I = I NL bzw.I=I IOL ).

[0374] Probability or probability density prob(θ i |d i , I) can have one or more factors. Here, each factor represents information about one or more parameters of a single eye model. For example, different independent parameters θ from different literature sources i 1 and θ i 2 The distribution of can be expressed as a product

[0375]

[0376] By prob(θ i |I), the parameters of the eye model may be inadvertently falsified. For example, if the "true" refraction is understood as a parameter of a single eye model, the most likely value of the "true" refraction may deviate from the measured refraction. If this is undesirable, then a carefully chosen range should be chosen (e.g. between -30 dpt and +20 dpt for the spherical equivalent M, and between -30 dpt and +20 dpt for the astigmatism components J0 and J1). 45 , ±5dpt) the corresponding parameters (e.g., equivalent spherical refraction) maintain a constant distribution.

[0377] If the parameters of the individual eye model or other variables related to the parameters or measurement data are known exactly or with high accuracy, their distribution can be approximated by a Dirac delta distribution. Equations involving these parameters or variables can be integrated on both sides, which can simplify subsequent calculations.

[0378] Description of the method

[0379] Two possible approaches to calculating spectacle lenses are described below (Bayesian A and Bayesian B). In the Bayesian A approach, the available information is used to build a (single) individual eye model, with the help of which the spectacle lens that best fits this eye model is calculated. The eye model can be, for example, composed of a parameter set Given or assigned, it makes the probability or probability density prob(θ i |d i ,I) is maximized. Other parameter sets can also be selected, such as expected value <θ i > or about the distribution prob(θ i |d i ,I) parameter θ i the median of

[0380] The Bayesian B approach is more advantageous than the Bayesian A - but computationally more demanding, as a subset of individual eye models with different parameter sets can lead to very similar (or even identical) characteristics (e.g. the refraction at a reference point of the spectacle lens, or the refractive error distribution of a given area of the spectacle lens, or similar criteria used to determine the quality of the spectacle lens). Overall, the spectacle lens calculated with the most probable individual eye model can thus represent the best correction for a subset of individual eye models that overall have a higher probability than the most probable individual eye model. It is therefore advantageous to search for a spectacle lens that best corrects the distribution of eye models, rather than simply determining the most probable individual eye model and manufacturing a spectacle lens for it.

[0381] In both approaches, a spectacle lens (e.g. a spectacle lens) can be calculated that is consistent with the available information.

[0382] Bayesian A approach

[0383] In particular, one or more of the following steps can be performed:

[0384] - providing an initial distribution of the parameters of the eye model (ideally as a multivariate probability distribution of all parameters of the eye model, possibly also as marginal distributions; the probability distribution corresponds to information on the distribution of the parameters of the eye model in the population) parameters of the eye model eye model;

[0385] - providing known (in the best case measured) data on individual eye characteristics (ideally with a probability distribution or measurement error; the probability distribution corresponds to the inaccuracy of the measurement)

[0386] The known data can include: known current subjective and / or objective refraction, known previous subjective and / or objective refraction (e.g. preoperatively), the refractive power and / or shape of a determined refractive surface of the eye and / or the position (most importantly the axial position), size and / or shape of a determined refractive surface of the eye and / or the position of the entrance pupil, the refractive index of the refractive medium, the refractive index distribution in the refractive medium, the opacity; these variables can possibly be determined depending on the accommodation of the eye on a fixation object (target) at a given near distance;

[0387] - determining the parameters of the individual eye model based on the initial distribution of the parameters of the eye model and the known or measured data of the individual eye using probabilistic calculations. Ideally, a probability distribution or e.g. a parameter set characterizing the maximum of the probability distribution is determined.

[0388] In particular, calculation methods such as Markov Chain Monte Carlo theory, variational inference, maximum likelihood, maximum a posteriori or particle filters can be used;

[0389] The goal here is to select parameters of the individual eye model that are consistent with the provided initial distribution of the eye model and the known data. The product of the probability or probability density of the data for the given parameters of the eye model and the probability or probability density of the eye model parameters is used as a measure of consistency.

[0390] - Calculation / optimization / selection of eyeglass lenses using at least one parameter of an individual eye model.

[0391] The initial distribution of the eye model parameters provided in the first step can be parameterized, such as a (possibly multivariate) normal distribution, another distribution from the exponential family, a Cauchy distribution, a Dirichlet process, or a set of samples, i.e., one or more (possibly multidimensional) datasets. If the initial distribution of the eye model parameters is parameterized, the parameters of that distribution are called "hyperparameters."

[0392] The third step (i.e., determining the parameters of the individual eye models) may comprise determining a multivariate probability distribution comprising the parameters of the individual eye models and the hyperparameters of the initial distribution of the eye model parameters. In order to calculate the parameter distribution of the individual eye models from this, the distribution must be marginalized, i.e., integrated over the hyperparameters. The integral can be solved using conventional numerical methods (e.g., using Markov Chain Monte Carlo theory or Hybrid Monte Carlo theory) and / or analytical methods. In this case, the probability or probability density of the eye model parameters can be calculated using the following equation:

[0393] prob(θ i |d i ,I)∝prob(d i |θ i ,I)∫dλprob(θ i ,λ|I)

[0394] =prob(d i |θ i ,I)∫dλ prob(θ i |λ,I)prob(λ|I)

[0395] Here, prob(θ i |λ,I) represents finding an individual eye model θ in a population characterized by the hyperparameter λ i The probability or probability density of the parameter. The integration is performed over the entire defined range of all hyperparameters λ.

[0396] Bayesian B method

[0397] As an alternative or in addition to the Bayesian A method, one or more of the following steps can be performed:

[0398] providing a distribution of at least one parameter of a single eye model;

[0399] Optimizing / calculating / selecting a virtual spectacle lens by using at least one parameter of the individual eye model, calculating a probability distribution of parameters of the virtual spectacle lens or calculating a spectacle lens set;

[0400] The purpose of manufacturing the spectacle lens is to make the manufacturing parameters of the spectacle lens most likely to reach the parameters of the virtual spectacle lens.

[0401] In the first step, a distribution similar to that calculated by Bayesian A methods 1 to 3 can be provided. In the second step, the most likely parameters L of the spectacle lens are determined i , that is, according to the probability distribution or probability density

[0402] prob(L i |d i ,I)=∫dθ i prob(θ i ,L i |d i ,I)=∫dθ i prob(L i |θ i ,I)prob(θ i |d i ,I)

[0403] =∫dθ i δ(L i -L(θ i ))prob(θ i |d i ,I)

[0404] Identify eyeglass lenses Parameters that make prob(L i |d i ,I) is maximized. Here, L i Initially represents the parameters of any eyeglass lens and in L i =L(θ i ) is the case with the parameter θ i The spectacle lens parameters created when optimizing the spectacle lens are based on the individual eye model. The Dirac function distribution is represented by δ(.).

[0405] The parameters of the spectacle lens may be, for example, vertex depth, refractive power at a spectacle lens reference point, refractive power distribution over a spectacle lens area, refractive error at a spectacle lens reference point or refractive error distribution over a spectacle lens area.

[0406] What is important is the function L(θ i ) can be nonlinear, so the probability density prob(θ i |d i ,I)(about θi ) with L(0 i ) is not necessarily mapped to the maximum probability density prob(L i | d i , I).

[0407] If the function L(0 i ) can be inverted individually, the above equation can also be solved by means of a partial integral. Other methods are possible, such as numerical methods or parameter inference methods, for example particle filters, Markov chain Monte Carlo, which can calculate the parameter distribution of the spectacle lens L i .

[0408] In the Bayesian A method and the Bayesian B method, independent of the number and type of variables known by the measurement (i.e. the data d i and the form of the likelihood prob(d i | 0 i , I)) and the number and type of parameters of the eye model 0 i , a consistent eye model is always produced (Bayesian A and B methods) and it is possible to select a spectacle lens parameter that matches the set of possible consistent eye models (Bayesian B method).

[0409] Example of solving inconsistency problems based on probabilistic considerations

[0410] Context of the maximum likelihood method

[0411] Basic procedure

[0412] The initial situation is that N parameters x i , 1 < i < N of a model are to be assigned and the following information can be used:

[0413] - the mean value μ i , the standard deviation σ i and the correlation coefficients p ij (1 < i, j < N) of these N parameters in the population;

[0414] - either no measurement values (k = 0) or k measurement values of these parameters 1 < i < k (with 1 < k < N) are available. The probability distribution of the measurement value of each parameter x i is described by a random variable X i . A measure of reliability is preferably available for each measurement value, for example the standard deviation of the random variable X i , 1 < i < k.

[0415] - q = N - k of these parameters have no measurement values.

[0416] - Overall, only K of the N parameters are independent, as the model requires consistency conditions that can be expressed by Q = N - K constraints.

[0417] Examples can be:

[0418] - Example without HOA

[0419] - Parameters (N = 15): cornea (SZA), lens anterior surface (SZA), lens posterior surface (SZA), visual obstacle (SZA), eye length, lens thickness, anterior chamber depth;

[0420] - Measured data (k = 13): cornea (SZA), lens anterior surface (SZA), lens posterior surface (SZA), visual obstacle (SZA), anterior chamber depth;

[0421] - Constraints (Q = 3): visual obstacle (SZA) = theoretical visual obstacle (SZA) (calculated from the specified eye model);

[0422] - Example with HOA (maximal radial order)

[0423] - Parameters (N = 103): cornea (SZA+HOA), lens anterior surface (SZA+HOA), lens posterior surface (SZA+HOA), visual obstacle (SZA+HOA), eye length, lens thickness, anterior chamber depth;

[0424] - Measured data (k = 101): cornea (SZA+HOA), lens anterior surface (SZA+HOA), lens posterior surface (SZA+HOA), visual obstacle (SZA+HOA), anterior chamber depth;

[0425] - Constraints (Q = 25): visual obstacle (SZA+HOA) = theoretical visual obstacle (SZA+HOA) (calculated from the specified eye model).

[0426] The basic problem to be solved is that, in case of measured values deviating from the overall mean, it has to be decided whether a measured value has to be discarded (e.g. if it is not trustworthy) or has to be adopted. If all measured values are themselves reasonable, but violate one of the consistency conditions, they do not necessarily all be adopted. Rather, a balance between the various measured values has to be sought: those with a very high measurement reliability should at least be almost preserved, while uncertain measured values are more likely to be adjusted. Preferably, the best possible values for all N parameters are identified from the known information.

[0427] The idea of the present invention is based in particular on the assumption that the parameters have certain (unknown but initially fixed) values. Under this assumption, the conditional probability density

[0428] P bed (X1,...,X N |x1,...,x N ) (1)

[0429] is established for the measurement results, where X1,...,X N are random variables that vary with the fixed given true values x1,...,x N of the parameters. Subsequently, the probability of the observed measurement values P par is then quantified by evaluating the function P bed of the measurement values k and marginalizing it to the remaining q = N - k (unmeasured) parameters:

[0430]

[0431] This probability density is understood as a function of the N parameters x1,...,x N The N parameter values that assume the maximum of this function are then preferably considered to be the best possible values (maximum likelihood method):

[0432]

[0433] As an alternative to the marginalization in equation 2, the N parameter values can also be defined by setting the last parameter equal to the average value of the population,

[0434] x i = μ i ,k+1≤i≤N (4)

[0435] while the first k parameters x1,...,x k are determined such that their expected values equal the measurement values:

[0436]

[0437] As a further alternative, instead of the maximum formation according to equation (3) or the expected value formation according to equation (5), the median can also be used as a criterion.

[0438] As a further alternative, the maximum formation according to equation (3) and the expected value formation according to equation (5) and the median determination can also be combined as required in order to determine the N parameter values.

[0439] Background of the maximum late entry

[0440] Prior knowledge about the population is described by a distribution The description, which can correspond to the Bayesian description of the prior, the total probability density of the measurement values and the model parameters is thus given by the distribution function

[0441] P ges (X1,...,X k |x1,...,x N )=P mess (X1,...,X k |x1,...,x N )×P pop (x1,...,x N ) (6)

[0442] It can correspond to the Bayesian description of the posterior, except for a constant. This is why this method is also called maximum posterior.

[0443] Preferably, P pop

[0444]

[0445] where μ is a vector of mean values and C is a covariance matrix:

[0446]

[0447] The measurements are described by a distribution P mess (X1,...,X k |x1,...,x N ).

[0448] Preferably, the measurements are independent

[0449] P mess (X1,...,X k |x1,...,x N )=P1 mess (X1|x1)...P k mess (X k |x k ) (8)

[0450] The entire distribution function P ges (except for the posterior pre-factor) is given by

[0451] P ges (X1,...,X k ;x1,...,x N )=P1 mess (X1|x1)…P k mess(X k |x k )×P pop (x1,...,x N )

[0452] (8a)

[0453] Particularly preferably, each measured value has an expected value xi and a standard deviation Normal distribution

[0454]

[0455] Then by inserting the normal distribution from equation (8b) into equation (8a) we get the overall distribution function P ges .

[0456] Maximize P ges As parameters x1,...,x N The function is a creative idea. In order to apply the maximum a posteriori criterion, it is best to form the derivative of the logarithm

[0457]

[0458]

[0459] If the distribution is a multivariate normal distribution, as is particularly preferred, equation (9) or equation (10) represents an equation with N equations and N variables x1, ..., x2 for solution. N A system of linear equations.

[0460] a) No constraints

[0461] If there are no constraints and equation (9) can be solved, then the results x1,...,x N This is particularly preferred if the distribution is a multivariate normal distribution and if the measurement uncertainty is significantly smaller than the range of variation in the population. The result is

[0462]

[0463] That is, for all parameters with available measured values, people essentially believe the measured values, and for the remaining values, obtain the overall mean μ i plus the offset Δx due to the correlation with the measured value i One embodiment of the present invention is to directly use the measured values ​​1≤i≤k and ignore their slight deviation caused by the underlying population.

[0464] b) Constraints

[0465] If there are constraints between the parameters, these are also satisfied by each member of the population.

[0466] The constraints can be described as

[0467]

[0468] i.e. by the parameters x1,...,x N of Q functions f j which can be combined in a vector f and by requiring that these functions should equal 0. The functions f j are preferably linear or linear approximations of the given constraints.

[0469] In the preferred case of a multivariate distribution, this has the result that the columns of the covariance matrix are linearly dependent, i.e. the covariance matrix has a rank r < N and therefore cannot be inverted any more. In this way the distribution density P pop (x1,...,x N ) cannot be specified any more.

[0470] One possibility in practice is to move one or more of the correlations p ij or the standard deviations s i contained in it by means of e and to determine x1,...,x N so that the covariance matrix C is regularized. The solution thus obtained automatically satisfies the constraint e -> 0.

[0471] In the context of the present application, it has been found that this method has disadvantages. On the one hand, the distribution in the population must be known, on the other hand, its covariance matrix is either singular or is poorly conditioned. If the correlations p ij and the standard deviations s i are investigated, then small inaccuracies or incomplete information in the information are sufficient for the covariance matrix to be regular, but subsequently possibly to generate numerically unstable solutions for the sought parameters.

[0472] However, in the context of the present application, it has been found that this problem

[0473]

[0474] or based on the distribution (maximum a posteriori method)

[0475]

[0476] For this, the substitution method can preferably be used.

[0477] Maximum likelihood method with constraints and substitutions

[0478] Assuming the first K parameters xu :=(x K ,...,x T ) a are independent, equation (12) solves the remaining Q=N-K dependent parameters x K+1 :=(x N ,...,x T ) u which can then be understood as a function x a (x u ) of the independent parameters x u and can be substituted into f. The constraint as a function of x

[0479] f(x u ,x a (x u ))=0 (14).

[0480] In the context of the present invention, it is not necessary to know the function x a (x u ) explicitly. In the context of the present invention, it is only necessary to know its Jacobian matrix According to the theorem of implicit functions, it is given by

[0481]

[0482] where is the quadratic Jacobian matrix f with respect to x a is the general rectangular Jacobian matrix f with respect to x u . Thus, the probability density P mess (x u ,x a (x u )) has to be maximized as a function of x u , i.e.

[0483]

[0484] The system of equations (16) K is the equation that can be solved for the parameters x u independent of K. The remaining parameters x a are obtained by inserting them into the context x a (x u ).

[0485] Maximum likelihood method with constraints and Lagrange parameters

[0486] As an alternative, it is within the scope of the present invention that the whole set of parameters can be considered as independent if the Lagrangian function is maximized instead of the function P mess (x1,...,x N )​

[0487] P mess,Lagrange (x1,...,x N ,λ)=P mess ,(x1,...,x N )+λf(x1,...,x N ) (17)

[0488] where λ = (λ1,...,λ Q ) is a one-dimensional vector of Lagrange multipliers Q. Then maximize

[0489]

[0490] Solving the unknowns (x1,...,x N ) and (λ1,...,λ Q ) of equation (18) N+Q gives the solution of the parameters.

[0491] In addition to handling constraints with substitution or long-range parameters, one can also use, as an alternative (e.g. in case of local vanishing gradient maximization of a function), a damped Hamiltonian formalism with friction terms.

[0492] Similarly, the method of equations (16) to (18) can be applied to a function P ges (x1,...,x N ) instead of P mess (x1,...,x N ) then represents Maximum a posteriori method with constraints .

[0493] Embodiment with concrete exemplifying numerical values

[0494] For simplicity, an eye which is rotationally symmetric about the optical axis and which therefore has neither a cylindrical prescription, nor a cylinder cornea, nor a cylinder lens surface, is considered as a starting case. Exemplary values and parameters before IOL surgery are detailed as follows:

[0495] S = -7.0 dpt; visual impairment (measured)

[0496] C = 41.2 dpt; diopters of the cornea (measured)

[0497] L1 = 7.82 dpt; diopters of the anterior lens surface (literature)

[0498] L2 = 13.28 dpt; diopters of the posterior lens surface (literature)

[0499] d CL = 3.6 mm; depth of the anterior chamber (measured) (19)

[0500] d L = 3.7 mm; lens thickness (literature)

[0501] n CL = 1.336; anterior chamber refractive index (literature)

[0502] n L = 1.422; lens refractive index (literature)

[0503] n LR = 1.336; vitreous refractive index (literature).

[0504] After IOL surgery, for example, the following values or parameters are transmitted:

[0505] Visual impairment (measured) (20)

[0506] Posterior lens surface (manufacturer information).

[0507] For simplicity, it is assumed that all other parameters after IOL surgery remain unchanged.

[0508] With the help of or equations

[0509]

[0510] The reduced retrovitreous length (D LR = n LR / d LR , where the vitreous length is d LR ; further, τ CL = d CL / n CL , τ L = d CLL / n L ), so that the eye length d A = d CL + d L + d LR . The vitreous length and the eye length are directly related, so in the following the vitreous length can be considered instead of the eye length.

[0511] If equation (21) is applied to the pre- and post-surgery situation, formally the IOL pre-surgery

[0512] D LR = 64.69 dpt (22a)

[0513] and formally after IOL surgery

[0514]

[0515] However, since the vitreous length cannot be changed by surgery, the inconsistencies present here can be solved within the scope of the invention.

[0516] To select the simplest example, the initial situation can be considered as one in which there are no variations and correlations in the base population and the visual impairment is only measured later and the IOL itself presents uncertainty:

[0517] Visual impairment (standard deviation measurement method)

[0518] Power of the back surface of the lens (manufacturer's tolerance) (23).

[0519] Now, within the scope of the invention, it can be determined that S IOL , the true values of L 2,IOL , as expected, will all deviate from equation (20).

[0520] In the example case, P pop ≡ 1 and the probability density of the distribution of S IOL , L 2,IOL , based on the measured values, is initially assumed to be

[0521]

[0522] However, now, the constraint is that S IOL , L 2,IOL must produce the same post-operative value D LR after inserting equation (21). Thus, the equation of the constraint is

[0523]

[0524] When solving L 2,IOL as a function of S IOL :

[0525]

[0526] This constraint means that only movement on the cut surface 30 shown in Figure 2 is possible.

[0527] If L 2,IOL (S IOL ) is substituted into equation (24) and S IOL is maximized, i.e., if for S IOL , it is solved that

[0528]

[0529] which obtains

[0530]

[0531] Thus, both variables S IOL ,L 2,IOL are in the negative direction, but to different degrees. In contrast, the method seeks a balance for different standard deviations and constraints with respect to the asymmetric position of the Gaussian clock.

[0532] Inconsistencies in the eye model can not only occur in the calculated eye length (or the calculated lens-to-retina distance), but also, for example, when measuring the eye length. Such inconsistencies can be resolved analogously to the example of the calculated eye length described above. Of course, more complex examples can also be given in which the eye length itself is not fixed or the relevant circumstances can occur.

[0533] List of reference signs

[0534] 10 main ray

[0535] 12 eye

[0536] 14 first surface of the lens (front surface)

[0537] 16 second surface of the lens (back surface)

[0538] 18 cornea front surface

[0539] 20 eye lens

[0540] 30 cut surface.

Claims

1. A computer-implemented method for identifying relevant individual parameters of at least one eye of a spectacle wearer for use in calculating or optimizing a spectacle lens for the at least one eye of the spectacle wearer, wherein an intraocular lens has been implanted in the at least one eye of the spectacle wearer as part of a surgery, the computer-implemented method comprising the following steps: - providing individual refractive data of said at least one eye of said spectacles wearer; - defining an individual eye model in which at least the following are defined as parameters of the individual eye model: - the shape and / or refractive power of the cornea of ​​the model eye (12); --The distance from the cornea to the lens; -- parameters of the lens of the model eye; --the distance from the lens to the retina, wherein the parameters defining the individual eye model are performed based on data of the vision correction of the at least one eye with the intraocular lens and also based on individual measurements and / or standard values ​​for the eye of the spectacles wearer and / or based on provided individual refractive data, so that the model eye (12) has the provided individual refractive data, wherein the data of the vision correction include the identified lens-to-retina distance and / or intraocular lens data, wherein the eye model is a constant eye model, and wherein an initial distribution of parameters of the eye model and individual data about characteristics of the at least one eye are provided, and wherein parameters of the individual eye model are determined based on the initial distribution of parameters of the eye model and the individual data using a probability calculation.

2. The computer-implemented method of claim 1 , wherein: a) in case of known intraocular lens data, defining the parameters of the individual eye model is performed based on the intraocular lens data and also based on individual measurements and / or standard values ​​of the eye of the spectacle wearer and / or based on provided individual refractive data, so that the model eye (12) has the provided individual refractive data, wherein the parameters of the lens of the model eye (12) are defined based on the intraocular lens data, and or b) without knowing the intraocular lens data, the lens-to-retina distance of the eye of the spectacle wearer is identified by measurement and / or based on an individual pre-operative eye model, and defining the parameters of the individual eye model is performed based on the identified lens-to-retina distance and also based on individual measured values ​​and / or standard values ​​of the eye of the spectacle wearer and / or based on the provided individual refractive data, so that the model eye has the provided individual refractive data, wherein the lens-to-retina distance of the model eye is defined by the identified lens-to-retina distance of the eye of the spectacle wearer.

3. A computer-implemented method according to claim 1, wherein defining the parameters of the individual eye model is performed based on intraocular lens data and also based on individual measurements and / or standard values ​​of the eye of the glasses wearer and / or based on provided individual refractive data, so that the model eye (12) has the provided individual refractive data, wherein defining the parameters of the lens of the model eye is performed based on the intraocular lens data.

4. A computer-implemented method according to claim 1 or 3, wherein the lens-to-retina distance of the eye of the glasses wearer is identified, and defining the parameters of the individual eye model is performed based on the identified lens-to-retina distance and also based on individual measurements and / or standard values ​​of the eye of the glasses wearer and / or based on the provided individual refractive data, so that the model eye (12) has the provided individual refractive data, wherein the lens-to-retina distance of the model eye (12) is defined by the identified lens-retina distance of the eye of the glasses wearer.

5. The computer-implemented method of claim 1, wherein defining the lens-to-retina distance is performed by measurement and / or calculation.

6. The computer-implemented method of claim 1 , wherein the intraocular lens data at least includes the defocus of the front surface of the intraocular lens, the defocus of the back surface of the intraocular lens and the thickness of the intraocular lens; and / or The intraocular lens data at least includes the defocus of the intraocular lens's diopter, and / or The intraocular lens data includes the specification of the A constant.

7. The computer-implemented method of claim 1, wherein the intraocular lens data is provided based on type or serial number information.

8. The computer-implemented method of claim 1 , further comprising the steps of: - consistency checks on the defined eye model, and - Resolve any inconsistencies with the help of analytical and / or numerical and / or probabilistic methods.

9. The computer-implemented method of claim 8, wherein any inconsistency is resolved by: adapting one or more parameters of the eye model; and / or adding at least one new parameter to the eye model and defining the new parameter such that the eye model becomes consistent; and / or The target diopter of the spectacle lens is adapted.

10. The computer-implemented method of claim 9, wherein a plurality of parameters of the eye model are adapted and the adaptation is divided among the plurality of parameters of the eye model.

11. The computer-implemented method of claim 1 , wherein the provided individual refractive data about the at least one eye of the spectacle wearer is individual post-operative refractive data of the at least one eye of the spectacle wearer, and wherein the individual eye model is a post-operative eye model.

12. The computer-implemented method of claim 11 , further comprising: - providing individual pre-operative refractive data of said at least one eye of said spectacle wearer, wherein Determining the lens-to-retina distance of the eye of the spectacle wearer is based on an individual pre-operative eye model using the provided individual pre-operative refractive data.

13. The computer-implemented method according to claim 12 , wherein in the pre-operative eye model at least the following items are defined based on individual measurements and / or standard values ​​of the eye of the spectacle wearer and / or based on the provided individual pre-operative refractive data: - the shape and / or refractive power of the cornea of ​​the model eye (12) of the preoperative eye model; - the cornea-to-lens distance of the model eye (12) of the preoperative eye model; - parameters of the lens of the model eye (12) of the preoperative eye model; - the lens-to-retina distance of the model eye (12) of the preoperative eye model, The model eye (12) is provided with individual pre-operative refractive data, wherein at least defining the lens-to-retina distance is performed by measurement and / or calculation.

14. The computer-implemented method of claim 1 or 13, wherein the shape and / or refractive power of the cornea comprises the shape and / or refractive power of the anterior corneal surface (18).

15. A computer-implemented method for calculating or optimizing a spectacle lens for at least one eye of a spectacle wearer, the method comprising: - A computer-implemented method for identifying relevant individual parameters of the at least one eye of a spectacle wearer according to any one of the preceding claims; - specifying a first surface (14) and a second surface (16) for the spectacle lens to be calculated or to be optimized; - identifying the path of the chief ray (10) entering the model eye (12) through at least one viewpoint (i) of at least one surface (14; 16) of the spectacle lens to be calculated or optimized; - evaluating the aberration of a wavefront resulting from a spherical wavefront incident on a first surface of the spectacle lens along a principal ray on an evaluation surface, compared to a wavefront converging at a point on the retina of the eye model; - iteratively changing the at least one surface (14; 16) of the spectacle lens to be calculated or to be optimized until the aberration evaluated corresponds to a predetermined target aberration.

16. A method for manufacturing a spectacle lens, comprising: - calculating or optimizing a spectacle lens based on the computer-implemented method for calculating or optimizing a spectacle lens according to claim 15; - manufacturing said spectacle lens calculated or optimized in the above manner.

17. A device for identifying relevant individual parameters of at least one eye of a spectacle wearer for calculating or optimizing a spectacle lens for the at least one eye of the spectacle wearer, the at least one eye of the spectacle wearer having an implanted intraocular lens, comprising: - at least one data interface for providing individual refractive data of said at least one eye of said spectacles wearer; - a modeling module for defining an individual eye model, said individual eye model defining at least the following as parameters of said individual eye model: - the shape and / or refractive power of the cornea of ​​the model eye (12); --The distance from cornea to lens; --Parameters of the lens of the model eye; - lens-to-retina distance, wherein the parameters defining the individual eye model are defined based on vision correction data of the at least one eye with the intraocular lens and also based on individual measurements and / or standard values ​​of the eye of the spectacles wearer and / or based on the provided individual refractive data, so that the model eye (12) has the provided individual refractive data, wherein the vision correction data include the identified lens-to-retina distance and / or intraocular lens data, wherein the eye model is a constant eye model, and wherein an initial distribution of parameters of the eye model and individual data about characteristics of the at least one eye are provided, and wherein parameters of the individual eye model are determined based on the initial distribution of parameters of the eye model and the individual data using a probability calculation.

18. The device according to claim 17, wherein the shape and / or refractive power of the cornea comprises the shape and / or refractive power of the anterior corneal surface (18).

19. A device according to claim 17, wherein the parameters of the individual eye model are defined based on intraocular lens data and also based on individual measurements and / or standard values ​​of the eye of the glasses wearer and / or based on provided individual refractive data, so that the model eye (12) has the provided individual refractive data, wherein the parameters of the lens of the model eye are defined based on the intraocular lens data.

20. Apparatus according to any one of claims 17 to 19, wherein the lens-to-retina distance of the eye of the spectacle wearer is identified by the modelling module, and defining the parameters of the individual eye model is performed based on the identified lens-to-retina distance and also based on individual measurements and / or standard values ​​of the eye of the spectacle wearer and / or based on the provided individual refractive data, so that the model eye (12) has the provided individual refractive data, wherein the lens-to-retina distance of the model eye (12) is defined by the identified lens-to-retina distance of the spectacle wearer.

21. A device for calculating or optimizing a spectacle lens for at least one eye of a spectacle wearer, comprising: - a device for identifying relevant individual parameters of said at least one eye of a spectacle wearer according to any one of claims 17 to 20; - a surface model database for specifying a first surface (14) and a second surface (16) for a spectacle lens to be calculated or to be optimized; a chief ray identification module for identifying the path of a chief ray (10) entering the model eye (12) through at least one viewpoint (i) of at least one surface (14; 16) of the spectacle lens to be calculated or optimized; an evaluation module for evaluating the aberration of a wavefront resulting from a spherical wavefront incident on the first surface of the spectacle lens along the principal ray on the evaluation surface, compared to a wavefront converging at a point on the retina of the eye model; - an optimization module for iteratively varying said at least one surface (14; 16) of said spectacle lens to be calculated or to be optimized until said aberration evaluated corresponds to a predetermined target aberration.

22. An apparatus for producing eyeglass lenses, comprising: a calculation or optimization device configured to calculate or optimize the spectacle lens based on the computer-implemented method for calculating or optimizing a spectacle lens according to claim 15; A processing device is configured to process the spectacle lens according to the calculation or optimization result.

23. A computer program product comprising a program code configured to, when loaded and executed on a computer, perform the computer-implemented method for identifying relevant individual parameters of at least one eye of a spectacle wearer according to any one of claims 1 to 14 and / or the computer-implemented method for calculating or optimizing spectacle lenses according to claim 15.

24. A spectacle lens produced by the method for producing a spectacle lens according to claim 16 and / or using the apparatus according to claim 21.

Images