FR3102845A1 - Determination of at least one optical parameter of an optical lens - Google Patents

Abstract

Title: Determination of at least one optical parameter of an optical lens The present invention relates to a method (210), a computer program and a device (110) for determining at least one optical parameter (220, 220',... ) of an optical lens (112) as well as a method for determining at least one optical parameter (220, 220', ...) of a pair of glasses (118), using the method for determining the optical parameters (220, 220', …) of the optical lens (112). The method (210) in this case comprises the following steps: a) capturing at least one image (234) of a pattern (124) through an optical lens (112), and b) determining at least an optical parameter (220, 220, 220') of the optical lens (112) from the at least one image (234) of the pattern (124), or from the at least one image (234) of the pattern (124) exhibiting an optically observable variation, at least two sets of data (242, 244, 246) with different characteristic values of the variation are extracted, and at least one optical parameter (220, 220', ... ) of the optical lens (112) from the at least two sets of data (242, 244, 246). The present invention makes it possible to determine with greater precision at least one optical parameter (220, 220′, …) of the optical lens (112). Furthermore, at least two optical parameters (220, 220', ...) of the optical lens (112) can be determined as simultaneously as possible, so that changes which may occur between two individual measurements are not taken into account when evaluation of the measurement results, thereby accelerating the evaluation of the measurement results and achieving higher accuracy of the measurement results. Figure 1

Description

Determination of at least one optical parameter of an optical lens

Field of the invention

The present invention relates to a method, a computer program and a device for determining at least one optical parameter of an optical lens as well as a method for determining at least one optical parameter of at least one spectacle lens. at least one pair of glasses, using the method for determining at least one optical parameter of at least one optical lens.

State of the art

Are known, in the state of the art, methods and devices for determining optical parameters of an optical lens, which will simply be briefly designated hereafter by "lens", in particular lenses which are used as spectacle lenses in a pair of glasses correcting refractive errors of a user's eye. The concept of "refraction" here refers to a light refraction in the user's eye, which an incident light ray undergoes which passes through the pupil inside the user's eye. For this purpose, a refractive index is usually indicated to measure the refraction of light. Due to refractive errors of the user's eye, defocusing may occur here which will be compensated to a great extent by, for example, the sphero-cylindrical design of the lens used as a spectacle lens, in order to thus allow a image quality as optimal as possible for the user.

There are different representation modes to describe the parameters of a sphero-cylindrical lens. In the case of spectacle lenses, the DIN EN ISO 13666:2013-10 standard, which will be referred to simply as "the standard", stipulates in paragraph 11.2 a "spherical refractive index", which is defined as the value maximum of a refractive index of a spectacle lens with spherical action or as the maximum value of a respective refractive index in one of the two main planes (meridians) of the spectacle lens with astigmatic effect. According to the standard, § 9.7.1 and 9.7.2, the "maximum refractive index value" is defined as the inverse of a paraxial focal distance of an image focal point, each time measured in meters. The sphero-cylindrical spectacle lens with astigmatic effect unites, according to the standard, § 12, a parallel paraxial light beam into two separate focal lines perpendicular to each other, and therefore has a maximum spherical refractive index in the two main planes. The "astigmatic effect" is defined here by the thickness of the cylinder and the position of the axis. "Cylinder thickness" according to standard § 12.5, here represents the value of an "astigmatic difference" which indicates the difference between the maximum spherical refractive indices in the two principal planes. The "position of the axis" represents according to the standard § 12.6 a direction of the main plane whose maximum refractive index is taken as reference value. Finally, according to standard § 12.8, the "power" of the spectacle lens with an astigmatic effect is indicated by three values comprising the maximum refractive indices of each of the two principal planes and the thickness of the cylinder. According to L. N. Thibos, W. Wheeler and D. Horner (1997), Power Vectors: An Application of Fourier Analysis to the Description and Statistical Analysis of Refractive Error, Optometry and Vision Science 74 (6), p. 367-375, any sphero-cylindrical lens can be described by the indication of a "refraction vector" (power vector), which can be precisely described by a point in a three-dimensional dioptric space. Three-dimensional dioptric space can be described by coordinates that correspond or are correlated to mean spherical refraction and cylinder thickness, as well as the corresponding axial position.

A measurement operation to determine the refractive index of a sphero-cylindrical lens can be based on a technical measurement of a magnification of a pattern operated by the lens. For this purpose, the refractive index, and with it the corresponding magnification, is determined for at least three main sections in order to be able to determine the spherical refractive index and the cylindrical refractive index. If one specifically determines an axial position of the cylindrical effect of the lens, in particular by determining the direction of a distortion of the pattern, one only needs to determine the magnification along two main sections. Until now, the methods are based on the sequential realization of the measurement method, where a different or identical pattern is used each time in different orientations to determine the desired magnification and to deduce the refractive index therefrom.

WO 2016/181310 A1 discloses various methods and devices which are designed to process the image of an object which has been captured by means of a lens of which at least one optical parameter is to be evaluated, and to determine the optical parameter of the lens based on the image of the object. The optical parameter is chosen between the spherical refractive index, the cylindrical refractive index and/or the axial position. To do this, each time an image of different patterns is captured through an optical lens, then at least one optical parameter of the optical lens is determined from the images of the pattern, the lens or the camera being moved between the captures of the different patterns. In particular, to determine the magnification produced by the lens, one can preferably use calibration objects placed outside the field of vision that the lens can observe, on a screen on which the object is located, and which are identified, for example, their color and/or their shape.

Object of the invention

In particular, starting from the publication of WO 2016/181310 A1, the object of the present invention consists in providing a method, a computer program and a device for determining at least one optical parameter of at least one optical lens as well as a method for determining at least one optical parameter of at least one spectacle lens of at least one pair of spectacles, which at least partly overcome the drawbacks and limitations mentioned in the state of the art .

In particular, the method, the computer program and the device must make it possible to determine at least one optical parameter with greater precision. Furthermore, at least two optical parameters of at least one optical lens can be determined as simultaneously as possible, so that changes which may occur between two individual measurements are not taken into account when evaluating the measurement results , thereby accelerating the evaluation of the measurement results and achieving higher accuracy of the measurement results.

Disclosure of Invention

This object is obtained by a method, a computer program and a device for determining at least one optical parameter of at least one optical lens as well as by a method for determining at least one optical parameter of at least one lens glasses at least one pair of glasses, with the characteristics set out below.

Thereafter, the verbs "to have", "to present", "to understand" or "to include" or any grammatical variation of these will be used in a non-exclusive way. Consequently, these terms can refer both to situations in which, in addition to the characteristic introduced by these terms, no other characteristic is present or to situations in which one or more other characteristics are present.

In a first aspect, the present invention relates to a method for determining at least one optical parameter of at least one optical lens. The method comprises the following steps a) and b), preferably in this order. Another order is also basically possible. In particular, a totally or partially simultaneous performance of the steps is also possible. Furthermore, one, several or all of the process steps can be repeated, in particular can be carried out more than once. The method can, in addition to the steps indicated, also comprise other method steps.

The method for determining at least one optical parameter of at least one optical lens comprises the following steps:

a) capture of at least one image of at least one pattern through at least one optical lens, and

b) determination of at least one optical parameter of the at least one optical lens from the at least one image of the at least one pattern,

where from the at least one image of the at least one pattern having an optically observable variation, at least two data sets of characteristic values different from each other of the variation are extracted, and at least one optical parameter of the at least one optical lens from the at least two data sets.

According to step a) of the present method, a capture of at least one image of at least one pattern is performed through at least one optical lens. In addition, it is possible to preferentially perform a representation of the at least one pattern on a screen. The term "screen" here refers to an electronically controlled display device which has a two-dimensional extension, where the desired at least one motif can be represented in a basically freely selectable representation, at any location in this expansion. The screen can here be chosen preferentially from a monitor, a screen and a display. Furthermore, the screen here can be included in a mobile communication device. The term "mobile communication device" includes here, in particular, a mobile telephone, a smartphone or a tablet. But one can nevertheless think of other types of mobile communication devices. In this way, the present method can, in practice, be carried out anywhere. Other types of screens are also possible.

The term "pattern" means any graphic structure preferably having at least one spatially oriented period, within which the structure of the pattern is repeatedly represented, dots or similar areas being able to form on the motif by the repetition of the structure. Preferred embodiments of dots or similar areas can preferentially be present in the form of periodic maxima or minima, in particular in the form of patterns in bands, circles or dots. Further, the pattern may otherwise include defined noise, e.g. white noise or pink noise, shades of gray, in which several periods are contained. The distribution of the possible shades of gray of each pixel of the screen being defined by mathematical random distributions. Other types of patterns are nevertheless possible.

Thus, the period of the at least one pattern can preferentially relate to a dimension of a periodic function, in particular a spatial frequency. The term "spatial frequency" here refers to the inverse of a spatial interval, which can be expressed in units 1/m or else or in addition, especially when the distance from the screen is known, as a number without dimension, for example by degree or by cycle, between two neighboring similar points, preferably between neighboring maxima or minima, in particular between two neighboring bands, circles or points, in a spatial periodic modification of the at least one pattern.

According to the invention, the at least one pattern has an optically observable variation. The term “variation” designates here a modification of at least one characteristic value of the at least one pattern. In a particularly preferred embodiment, the variation of the at least one pattern may relate to a modification of at least one parameter of the at least one pattern, in particular a dimension of the spatial frequency and/or of the spatial orientation of the at least one pattern, preferably in at least a stripe, circle, dot, noise pattern or a combination thereof. But one can nevertheless think of other types of variation. The term "characteristic value" designates here a numerical or alphanumerical value or a quantity which can be uniquely assigned to a numerical or alphanumeric value, by which the chosen variation can be defined unequivocally. The term "optically observable" designates a property of the variation of the at least one pattern which makes it possible to grasp the modification made of the at least one pattern in the form of at least one image, to recognize it in the at least one pattern. at least one image of the at least one pattern, and thus to highlight it optically. Preferably, the possibility of optical detection is identified using an optical sensor or an optical detector, e.g. a camera or a CCD sensor. Thanks to an electronic control, the variation of the at least one pattern can be done easily and on a large scale, with at least two characteristic values different from each other. Preferably, each of the characteristic values of the variation of the at least one pattern can be correlated to a modulation of the at least one pattern, the modulation preferably being able to be chosen from at least one chromatic, spatial or temporal modulation of the at least one pattern. The term "modulation" designates here a modification of at least one parameter of the at least one pattern, which is correlated to a corresponding characteristic value of the variation of the at least one pattern, in order to be able to highlights the variation of the at least one pattern in the at least one image, as explained in more detail below. Here, we prefer the choice of a single type of modulation, but a combination of at least two types of modulation is also possible, for example the association of a spatial modulation and a chromatic modulation. It is nevertheless possible to think of other types of modulation, for example a modulation from the point of view of the polarization of the at least one pattern.

In a preferred embodiment, the characteristic values of the variation of the at least one pattern can be correlated with a chromatic modulation. Here, the at least one pattern can constitute a superposition of at least two partial patterns, preferably two, three or four partial patterns, each having a characteristic value different from the others, in particular a respective spatial frequency and/or orientation different from the at least one pattern, and a color which is respectively correlated thereto, which are represented on the screen in superimposed form. To do this, it is possible to choose in a colorimetric space at least two, preferably two, three or four colors as magnitude correlated to the respective characteristic value of the variation of the at least one pattern. The term "color space" here means a set of colors that can be provided by means of a color model. Here, the at least one pattern can be represented in the respective different color depending on the corresponding characteristic value of the at least one pattern, preferably in the different color channels of the screen. For example, one can choose as characteristic values the colors for each of three partial patterns in the RGB color space based on the three fundamental colors red, green and blue. A first partial pattern can here be assigned as corresponding characteristic value red, a second partial pattern can be assigned as corresponding characteristic value green and a third partial pattern can be assigned as corresponding characteristic value blue. Instead of the red, green and blue characteristic values, a wavelength of the color in the electromagnetic spectrum or a code in the corresponding color space can be indicated as characteristic values. Another way of selecting colors and indicating their corresponding characteristic value is nevertheless possible, in particular the CMYK color space, which includes the following three fundamental colors: cyan, magenta and yellow, as well as a proportion of black designated by "key" ("Key"), or for example the CIELab colorimetric space.

In an alternative embodiment, the characteristic values of the variation of the at least one pattern can be correlated with a spatial modulation of the at least one pattern. Here, the at least one pattern can admit, in at least two, preferably two, three or four partial zones of the at least one pattern delimited in space with respect to each other, respectively another characteristic value for the variation, in particular a different respective spatial frequency and/or orientation for the at least one pattern. The term “partial zone” here relates to a section of the at least one pattern, comprising a locally limited surface. Here, the representation of the at least one pattern on the screen can be modified by selecting the corresponding values in the different partial areas, so that a spatially different representation of the at least one pattern in the partial areas different from the at least one pattern can be performed on the screen. For example, the intervals between two neighboring bands, circles or points can be indicated in a unit, for example in mm, in pixels or in degrees, respectively as characteristic value of the variation. For example, a first partial area can be assigned as corresponding characteristic value 4 mm, a second partial area can be assigned as corresponding characteristic value 5 mm and a third partial area can be assigned as corresponding characteristic value 6 mm. Another way of selecting the spatial variation and the indication of its respectively corresponding characteristic value is nevertheless possible, for example a variation of the orientation of a striped pattern, for example a direction of 0°, 120° and 240° relative to a chosen direction. However, other examples are possible. This configuration of the variation of the at least one pattern can be suitable preferentially when determining at least two optical parameters of at least one multifocal lens, which can be used in particular as a progressive spectacle lens. In this way, the magnification in different partial spatial regions of the at least one multifocal lens can be determined by measuring techniques and the corresponding refraction can be deduced therefrom.

In a further alternative embodiment, the characteristic values of the variation of the at least one pattern can be correlated with a temporal modulation of the at least one pattern, which can also be designated by “frequency modulation”. Here, in a given time interval, at least two, preferably two, three or four different characteristic values from each other of at least one pattern, in particular a different respective spatial frequency and/or orientation for the au least one pattern, according to a defined temporal succession, can be represented on the screen and captured by the camera. The term “frequency” designates here the inverse of a time value between two images represented consecutively with characteristic values different from each other. Preferably, the frequency of the representation of the different characteristic values can be synchronized with the image capture frequency of the camera, so that an unambiguous temporal assignment of the characteristic values is possible. In addition to a temporal variation of different characteristic values of the at least one pattern, it is also possible to use alternatively or additionally different patterns in a temporal variation. This may be particularly preferred if different lens optical parameters can be preferentially determined with different patterns. The frequency can preferably correspond here to what is called an "image frequency" or a "frame frequency" of the screen and/or of the camera. We are thus talking about a frequency at which we can represent images, that is to say here the images of at least one pattern of at least one image, on a screen or capture them with a camera, the frequency which can range from 1 Hz to 250 Hz, preferably from 20 Hz to 50 Hz. This is why the "time interval" mentioned above can preferably be a maximum of 1 s, particularly preferably a maximum of 0.05 s, in particular of maximum 0.004 s. However, other frequency or time interval values can be envisaged. The words "simultaneously" and "simultaneously" used in this document relate to the capture of the at least one image of the at least one pattern according to step a) in this time interval. In particular, contrary to patent WO 2016/181310 Al, both the representation on the screen, according to a defined temporal succession, of the at least one pattern preferentially presenting simultaneous characteristic values by a chromatic, spatial and temporal association mentioned more top, that the capture, preferably synchronized, of the at least one pattern by means of the camera, takes place here without the screen, the at least one optical lens or the camera being moved in the meantime .

According to step b), the determination of at least one optical parameter of the at least one optical lens is made from the at least one image of the at least one pattern. The word “image” designates a two-dimensional representation of the at least one pattern, created by a camera. This may be a single representation of the at least one pattern or a temporal succession of representations of the at least one pattern. We will also call the sequence "video". The term "camera" here designates an image pickup device which is designed to capture at least one image of the at least one pattern and which, therefore, is aligned with the at least one pattern. To do this, the at least one optical lens, for which at least one optical parameter is to be determined, can be installed at a location located in the space between the screen and the camera so that the camera can capture at least an image of the at least one pattern which is modified by the presence of the at least one optical lens at this location. Contrary to the state of the art, as described in particular in WO 2016/181310 Al, it is here possible to dispense with a repetition of steps a) and b), because a single image may be sufficient to be able to carry out the desired determination of the at least one optical parameter of the at least one optical lens.

The term "optical parameter" designates a quantity characteristic of the optical lens, in particular of a sphero-cylindrical lens. As mentioned at the start, there are different modes of representation for this purpose. In particular, for spectacle lenses, standard § 11.2 stipulates a "spherical refractive index", which is defined as the maximum value of the refractive index of a spectacle lens with spherical action or as the maximum value of the respective refractive index in one of the two main planes (meridians) of the spectacle lens with astigmatic effect. According to the standard, § 9.7.1 and 9.7.2, "the maximum refractive index" is defined as the inverse of a paraxial focal distance of an image focal point, each time measured in meters. For the sphero-cylindrical spectacle lens with astigmatic effect, the thickness of the cylinder and the axial position are indicated. "Cylinder thickness" according to standard § 12.5, here represents the value of an "astigmatic difference" which indicates the difference between the maximum refractive indices in the two main planes. The "position of the axis" designates according to the standard § 12.6 a direction of the main plane whose maximum refractive index is taken as reference value. Finally, according to standard § 12.8, the "thickness" of the spectacle lens with an astigmatic effect is indicated by three values comprising the maximum refractive indices of each of the two main planes and the thickness of the cylinder. An alternative mode of representation can be found in L. N. Thibos, W. Wheeler & D. Horner (1997), Power Vectors: An Application of Fourier Analysis to the Description and Statistical Analysis of Refractive Error, Optometry and Vision Science 74 (6), p . 367-375, which proposes the indication of a "refraction vector" (power vector) to describe any sphero-cylindrical lens, which can be described by precisely a point in a three-dimensional dioptric space. The three-dimensional diopter space can be defined by coordinates that correspond or are correlated to the spherical mean refraction and to the cylindrical thickness as well as to the corresponding axis position.

As mentioned at the start, the presence of the at least one optical lens in a place located in the space between the screen and the camera, can generate a magnification of the at least one pattern that the camera can capture. The term “magnification” designates here a factor ≥ 1 of difference between an interval or a distance in at least one image of the at least one pattern and the same interval or the same distance in the representation of the at least one pattern at the screen, and can therefore also, depending on the type of the at least one optical lens chosen, include shrinkage, insofar as the term "shrinkage" designates a factor < 1. To determine the magnification from the at least one image of the at least one pattern, known methods can be implemented, in particular a 1D Fourier transform of a profile along a given direction in at least one image, a 2D Fourier transform of a partial zone of the at least one image or an adaptation (fitting) of geometric shapes. The magnification can further be decomposed into vector components and thus be used to determine the properties of the sphero-cylindrical optical lenses. To determine the at least one optical parameter of the at least one optical lens, in particular the refractive index of a sphero-cylindrical lens, those skilled in the art can evaluate by measurement techniques the magnification determined from the at least one pattern by the at least one optical lens by methods known to those skilled in the art. Preferably, an evaluation unit can be used which performs the desired determination of the at least one optical parameter of the at least one optical lens from the at least one image of the at least one pattern. Preferably, the at least one optical lens is placed between at least one pattern and at least one optical detector, eg. a camera. By having knowledge of the distances between the at least one pattern, the at least one optical lens and the at least one optical detector, the magnification of the at least one pattern can be determined by measurement techniques. The magnification is then calculated by comparing at least one image with at least one optical lens and at least one image without an optical lens. Magnification can be indicated here as a ratio between an angle of view of the image and an angle of view of the object. By angle is meant the ratio, calculated from the height and distance of the object from a lens, as well as calculated from an image height and width, these values being determined by the refractive index of the lens. For other properties, one can for example refer to Hering, E., & Martin, R. (2017). Optik für Ingenieure und Naturwissenschaftler: Grundlagen und Anwendungen. Carl Hanser Verlag GmbH Co KG. p. 107-136. However, other methods of determining the magnification are possible, for example image analysis algorithms for different image statistics parameters, such as e.g. edge orientation, distortion, direction and trace optical flow, gray value distribution, local and global motion. Thanks to a previously trained neural network, such as support vector machines (SVM – Support Vector Machines), convolutional neural networks (CNN – Convolutional Neuronal Networks) or non-linear regression modeling using Bayesian optimization of hyperparameters, we classify these different statistical image parameters from the point of view of the lens parameter, e.g. of its refractive index.

As already mentioned above, the at least one pattern chosen according to the invention has an optically observable variation, the effect of which on the optical parameters of the at least one optical lens is determined by measurement techniques. To determine at least one optical parameter of the at least one lens, the invention extracts from the at least one image of the at least one pattern at least two, preferably two, three or four sets of data from respective different characteristic values of the variation. The term "extract" here designates the extraction of information from the at least one image, which are assigned respectively to the corresponding characteristic value of the variation. The term "data set" here designates a plurality of data values extracted from the information included in the at least one image. Preferably, the data set can here comprise at least one partial pattern, which is assigned to a value characteristic of the variation of the at least one pattern. In a preferred embodiment, in which the characteristic values of the variation of the at least one pattern are correlated to a chromatic modulation of the at least one pattern, each of the at least two data sets can comprise values from a respectively associated color channel of the camera. In another preferred embodiment, in which the characteristic values of the variation of the at least one pattern are correlated to a spatial modulation of the at least one pattern, each of the at least two data sets can comprise values resulting from a respective partial zone of the at least one image of the at least one pattern. In another preferred embodiment, in which the characteristic values of the variation of the at least one pattern are correlated with a temporal modulation of the at least one pattern, each of the at least two sets of data can comprise values from each times of one of the consecutively captured images of the at least one pattern. Additionally, datasets are possible, which may include a combination of the aforementioned values and/or additional information. The additional information can here be collected in the form of at least one additional data value in the indicated data set. Otherwise or in addition, the additional information can be taken into account in at least one data value already present in the data set.

In the preferred embodiment in which the characteristic values of the variation of the at least one pattern are correlated with a chromatic modulation, it is possible to extract from the pattern at least two, preferably two, three or four partial patterns contained in the at least a pattern in the form of an overlay, each of which exhibits a different color from the others, depending on the color as the respective characteristic value. Here, as already mentioned above, the at least one pattern can be represented in the respective color as a function of the corresponding characteristic value, preferably in the different color channels of the screen. Once the at least one image has been captured with a camera, the image captures can be worked on independently of each other in each color channel of the camera, so as to be able to analyze the images independently of each other. modified partial patterns represented in each color channel as datasets. Alternatively or additionally, recognition of each partial pattern can be carried out during the analysis, in particular by recognition of the at least one pattern itself, for example by its orientation, or by means of corresponding markings on the screen out of the at least one pattern which can serve as a calibration object. Preferably, the analysis of the individual partial patterns can here take place by parallel processing, which makes it possible to significantly reduce the processing time - contrary to the state of the art.

Similarly, in the alternative embodiment in which the characteristic values of the variation of the at least one pattern are correlated with a spatial modulation, it is possible to extract from the at least one captured image the at least two, preferably two, three or four partial zones of the at least one pattern delimited in space with respect to each other, which each correspond to a respective characteristic value of the variation, by image processing. Alternatively or in addition, recognition of each partial pattern can also be carried out here during the analysis, in particular by recognition of the at least one pattern itself, for example by its orientation, or by means of markings corresponding to the at least one pattern that can serve as a calibration object. Here too, the analysis of each partial zone can preferably be done by processing in parallel to significantly reduce the processing time.

Similarly, in the alternative embodiment in which the characteristic values of the variation of the pattern are correlated with a temporal modulation, it is possible to evaluate the at least two, preferably two, three or four successive image captures different from each other with respect to the respective characteristic value of the variation. The separate analysis of each partial pattern can be made possible here by time synchronization of the screen and the camera already during the performance of the measurement. Alternatively or in addition, recognition of each partial pattern can also be carried out here during the analysis, in particular by recognition of the at least one pattern itself, for example by its orientation, or by means of markings corresponding to the at least one pattern that can serve as a calibration object.

In a particular embodiment, relative differences between each data set, in particular between image captures in each color channel or between time-varying frames, can be compared with each other, preferably with respect to relative magnification or a relative orientation of at least two variations of the at least one pattern and integrating them into the evaluation. Assuming that different color channels are used for the analysis along different meridians, the following comparisons can be preferentially made here:

- comparison of the magnification, the magnification being able to be chosen according to the image captures in the various color channels, in particular to determine a maximum or a common minimum;

- comparison of a ratio of the magnification in the different color channels, in particular as a function of the magnification along different meridians;

- comparison of a change in the orientation of the at least one pattern in different color channels, in particular to determine the axial position and/or the orientation of the at least one optical lens with respect to the au less a pattern itself;

- detection of a temporal variation of the at least one pattern;

- detection of the at least one pattern represented according to a temporal succession.

Compared to known methods in the state of the art, the parallel method presented here is significantly less error-prone and more time-efficient, because such a comparison of the relative differences in the sequential measures used according to the state of art, with modified patterns, is only possible if all measurement parameters have been fixed, in particular a screen-optical lens interval, an optical lens-camera interval, or the orientation of the screen, of the optical lens and the camera.

Since, as mentioned above, the capture of the at least one image of the at least one pattern according to step a) is done through the at least one optical lens, the at least one optical lens which is must determine the at least one optical parameter which can modify by its presence the at least one image of the at least one pattern, it is possible to fundamentally determine at least one optical parameter of the at least one optical lens from the at least one captured image. Since according to the invention, in addition, at least two sets of data of characteristic values different from each other are extracted from the variation of the at least one pattern, it is possible in this way to determine at least one optical parameter of the at least an optical lens from the at least two sets of data. The determination of the magnification can here be carried out independently, in particular for the at least two image captures, and thus preferably in parallel for different partial areas or partial patterns. In a particular embodiment, in particular in case of corresponding synchronization, it is also possible to capture the respective at least one pattern once more without using the at least one optical lens. This can be advantageous, in particular if the at least one pattern or its values are not known.

The variation of the at least one pattern, which takes place during the sequential succession of the individual measurements according to the state of the art, can be done in parallel with the method described here, which makes it possible in particular to reduce the time required. Moreover, a simultaneous determination of at least two sets of data makes it possible to exclude undesirable modifications of parameters, for example a change of position and/or orientation of the screen and/or of the optical lens and/or of the camera. The determination of at least two sets of data, respectively with different variations of the at least one pattern, can lead to an increase in the accuracy of the measurement results in a time interval corresponding to a sequential measurement, because in this interval of time, an increased number of variations of the at least one pattern are available for analysis. The determination of at least two data sets, respectively with different variations of the at least one pattern, can also lead to an increase in the accuracy of the measurement results in a time interval smaller than the time interval of a sequential measurement, insofar as in this shorter time interval, a higher number of variations of the at least one pattern are available for the analysis than in the sequential measurement.

In a particular embodiment, it is also possible to determine by image processing, from the at least one image captured by the camera, also preferably in the evaluation unit, geometric data of the at least one optical lens and/or a frame comprising the at least one optical lens as a spectacle lens. Preferably, one can here set aside one of the color channels during the display of the at least one partial pattern, to use it later to recognize the at least one optical lens, of the at least one eyeglass lens and/or frame. Without disturbing partial pattern in the background, which can have a disturbing effect in particular when highlighting the edges of the frame, detection of the zone occupied by the at least one optical lens can therefore be done with more precision in the at least one captured image, whereby for example a subdivision of the at least one optical lens into different partial areas is facilitated, for example for the analysis of multifocal lenses. The geometric data of the two spectacle lenses of at least one frame can advantageously be determined simultaneously.

In a preferred embodiment, each step of the method mentioned above for determining at least one optical parameter of at least one optical lens is carried out using at least one mobile terminal. By at least one “mobile terminal”, it is preferably meant a device which comprises at least one programmable processor as well as at least one camera. In the at least one mobile terminal, other components may be present, such as for example at least one screen, at least one light source, for example of visible light in a wavelength range from 380 nm to 780 nm . Typical examples of this type of mobile terminal are smartphones or tablet PCs which may have at least one screen, for example a touchscreen (Touchscreen), at least one camera, and other components, such as at least one light source, wireless interfaces for mobile telephony or WLAN (wireless LAN). The representation of the at least one pattern can be done, for example, by means of the at least one screen of the at least one mobile terminal. The screen does not have to be part of the mobile terminal but can be a separate screen. The capture of at least one image of at least one pattern through at least one optical lens according to step a) of the method according to the invention can be done, for example, by means of the at least one camera or by means of the at least one light source and by means of the at least one camera or of the at least one light sensor, respectively of the at least one mobile terminal. The determination of the at least one optical parameter of the at least one optical lens on the basis of the at least one image of the at least one pattern, or from the at least one image of the at least one at least one pattern having an optically observable variation, at least two data sets of characteristic values different from each other of the variation are extracted, and where the at least one optical parameter of the at least one optical lens is determined from the at least one least two sets of data, can, for example, be done by means of the at least one programmable processor of the at least one mobile terminal.

In another aspect, the present invention relates to a computer program for determining at least one optical parameter of at least one optical lens, the computer program being designed to implement the determination of the at least one optical parameter of the at least one optical lens according to the method described herein for determining at least one optical parameter of at least one optical lens.

The method proposed here for determining at least one optical parameter of at least one optical lens is particularly suitable for use in a method for determining at least one optical parameter of at least one spectacle lens of at least a pair of glasses or a contact lens. The term “pair of spectacles” designates here any element which comprises two individual spectacle lenses and a frame, the spectacle lens being designed to be introduced into a frame which is chosen by a user of the pair of spectacles. Instead of the term “user” used here, the words “subject”, “carrier”, “user” or “participant” can also be used in the same sense. According to the standard, § 8.1.1 and 8.1.2, "spectacle lens" means an optical lens intended to be used to correct a vision defect in the eye, the optical lens being worn in front of the wearer's eye but not – unlike a contact lens – in contact with the eye.

In another aspect, the present invention thus relates to a method for determining at least one optical parameter of at least one spectacle lens of at least one pair of spectacles, the determination of the at least one optical parameter of the at least one eyeglass lens of at least one pair of eyeglasses being made according to the method described herein for determining at least one optical parameter of at least one optical lens. At least one optical parameter of the two spectacle lenses of at least one pair of spectacles can advantageously be determined simultaneously.

In particular, it is possible to determine from the determination of the optical parameter or parameters of the at least one optical lens a sphero-cylindrical lens which can be used as a spectacle lens to compensate for a refractive error manifesting itself as a defocusing of the eye, so that the best possible image quality can be obtained for the user. In a particular embodiment, the at least one pattern can be represented first in a first direction, then in a second direction which differs from the first direction and can here preferably be perpendicular to the first direction. The word "perpendicular" designates here an angle of 90° ± 30°, preferably of 90° ± 15°, particularly preferably of 90° ± 5°, in particular of 90° ± 1°. Other angles between the first and the second direction are nevertheless possible. It is thus possible to determine consecutively for the sphero-cylindrical eyeglass lens with astigmatic effect the maximum refractive indices of each of the two main planes orthogonal to each other.

In another aspect, the present invention relates to a device for determining at least one optical parameter of at least one optical lens. According to the invention, the device comprises:

- a camera designed to capture at least one image of at least one pattern through at least one optical lens, and

- an evaluation unit designed to determine at least one optical parameter of the at least one optical lens from the at least one image of the at least one pattern,

wherein the evaluation unit is further designed to extract from the at least one image of the at least one pattern exhibiting an optically observable variation at least two data sets of characteristic values different from each other of the variation, and for determining at least one optical parameter of the at least one optical lens from the at least two sets of data.

In a particularly preferred embodiment, the evaluation unit can here be designed to extract at least two image captures from respectively one color channel of the camera distinct from the other, which can be used as a data set. In an alternative embodiment, the evaluation unit can be designed to extract the at least two image captures of respectively a partial area of the image, which can here be used respectively as a data set. In an alternative embodiment, the evaluation unit can be designed to extract the at least two image captures for respectively a modulation frequency and use them respectively as a data set. Other embodiments for creating the at least two data sets are possible.

In a particularly preferred embodiment, the device may further comprise a screen designed to represent the at least one pattern and to introduce the optically observable variation in the at least one pattern. As already mentioned, the screen can here be chosen preferentially from a monitor, a screen and a display. Other types of screens are nevertheless possible.

In a particular embodiment, the device can also have a lighting device, in particular in order to be able to detect the modification of the at least one pattern through the at least one optical lens in high resolution thanks to the camera. Alternatively or additionally, use may be made of natural light or lighting produced in particular by the screen.

In a preferred embodiment, the device can be arranged in the form of at least one mobile terminal. For optional definitions and embodiments of the device in the form of at least one mobile terminal, including the characteristics it contains, reference will be made to the description of the method for determining at least one optical parameter of at least an optical lens in this document by means of at least one mobile terminal.

For other optional definitions and embodiments of the computer program and of the device for determining at least one optical parameter of at least one optical lens as well as of the method for determining at least one optical parameter of at least one eyeglasses of at least one pair of eyeglasses, including the characteristics they contain, reference is made to the description above or below of the method for determining at least one optical parameter of at least one optical lens .

In summary, within the scope of the present invention, the following embodiments are particularly preferred:

Embodiment 1. Method for determining at least one optical parameter of at least one optical lens, the method comprising the following steps:

a) capture of at least one image of at least one pattern through at least one optical lens; And

b) determination of at least one optical parameter of the at least one optical lens from the at least one image of the at least one pattern,

where, from the at least one image of the at least one pattern exhibiting an optically observable variation, at least two data sets of characteristic values different from one another of the variation are extracted, and at least one optical parameter of the at least one is determined at least one optical lens from the at least two data sets.

Embodiment 2. Method according to the previous embodiment, the at least two sets of data being extracted simultaneously from the at least one image of the at least one pattern.

Embodiment 3. Method according to one of the preceding embodiments, in which the at least two sets of data are extracted from the at least one image of the at least one pattern in a time interval, the interval time being a maximum of 1 s, preferably a maximum of 0.05 s, in particular a maximum of 0.004 s.

Embodiment 4. Method according to one of the preceding embodiments, in which each characteristic value of the variation of the at least one pattern is correlated with a modulation of the at least one pattern.

Embodiment 5. Method according to one of the preceding embodiments, in which the modulation is chosen from among a chromatic, spatial or temporal modulation of the at least one pattern.

Embodiment 6. Method according to the previous embodiment, in which the chromatic modulation of the at least one pattern is carried out by superimposing the at least one pattern from at least two partial patterns each having a distinct color.

Embodiment 7. A method according to the previous embodiment, wherein the at least two partial patterns are extracted from the at least one image as the at least two data sets.

Embodiment 8. Method according to one of the four preceding embodiments, in which the spatial modulation of the at least one pattern takes place by at least one difference of the at least one pattern in at least two partial regions different from each other of the at least one pattern.

Embodiment 9. Method according to the previous embodiment, wherein the at least two partial areas of the at least one pattern are extracted from the at least one image as the at least two data sets.

Embodiment 10. Method according to one of the six preceding embodiments, in which the temporal modulation of the at least one pattern is carried out by at least two patterns represented in temporal succession.

Embodiment 11. Method according to the previous embodiment, in which the at least two patterns represented according to a temporal succession are distinguished by at least one characteristic value of the variation of the pattern.

Embodiment 12. Method according to one of the two preceding embodiments, in which the at least two sets of data are extracted from the at least two images of the patterns represented consecutively according to a temporal succession.

Embodiment 13. Method according to one of the three preceding embodiments, wherein the at least one pattern is represented at a frequency of 1 Hz to 250 Hz, preferably 20 Hz to 50 Hz.

Embodiment 14. Method according to one of the four preceding embodiments, in which the at least one pattern is represented on the screen without any relative movement of the at least one pattern with respect to the at least one optical lens or to a camera.

Embodiment 15. Method according to one of the preceding embodiments, in which account is taken of the relative differences between the at least two sets of data of the characteristic values which differ between them of the variation.

Embodiment 16. A method according to one of the preceding embodiments, wherein the at least one pattern is displayed on a screen.

Embodiment 17. A method according to the previous embodiment, wherein the screen is selected from a monitor, a screen, and a display.

Embodiment 18. A method according to one of the preceding embodiments, wherein the at least one pattern has a graphic structure which has at least one spatially oriented period.

Embodiment 19. A method according to the previous embodiment, wherein the structure of the at least one pattern is repeatedly represented over the spatially oriented period.

Embodiment 20. A method according to the previous embodiment, wherein dots or similar areas are formed on the at least one pattern by repeating the structure.

Embodiment 21. A method according to the previous embodiment, wherein the points or similar areas are in the form of periodic maxima or minima.

Embodiment 22. A method according to one of the preceding embodiments, wherein the at least one pattern is selected from a stripe, circle or dot pattern.

Embodiment 23. Method according to one of the preceding embodiments, wherein the at least one pattern is first represented in a first direction, then in a second direction different from the first direction.

Embodiment 24. A method according to the previous embodiment, wherein the second direction is perpendicular to the first direction.

Embodiment 25. Method according to the previous embodiment, in which the maximum refractive indices of each of the two principal planes orthogonal to each other for a sphero-cylindrical spectacle lens with an astigmatic effect are determined consecutively.

Embodiment 26. A method according to one of the preceding embodiments, wherein the at least one pattern is known.

Embodiment 27. A method according to one of the preceding embodiments, the method being performed at least twice.

Embodiment 28. Process according to the previous embodiment, the process being carried out at least twice with the same at least one pattern.

Embodiment 29. Computer program for determining at least one optical parameter of at least one optical lens, the computer program being designed to carry out the steps according to one of the preceding embodiments.

Embodiment 30. Method for determining at least one optical parameter of at least one spectacle lens of at least one pair of spectacles, the determination of the optical parameters of the at least one spectacle lens being carried out according to the method according to one of the preceding embodiments.

Embodiment 31. Device for determining at least one optical parameter of at least one optical lens, the device comprising:

- a camera designed to capture at least one image of at least one pattern through at least one optical lens, and

- an evaluation unit designed to determine at least one optical parameter of the at least one optical lens from the at least one image of the at least one pattern,

wherein the evaluation unit is further designed to extract from the at least one image of the at least one pattern exhibiting an optically observable variation at least two data sets of characteristic values different from each other of the variation, and for determining at least one optical parameter of the at least one optical lens from the at least two sets of data.

Embodiment 32. Device according to the previous embodiment, where the evaluation unit is designed to extract the at least two sets of data from image captures of a color channel distinct from the others of the camera .

Embodiment 33. Device according to one of the two previous embodiments, where the evaluation unit is designed to extract the at least two sets of data from image captures of at least one respective partial area of at least one image.

Embodiment 34. Device according to one of the three preceding embodiments, in which the evaluation unit is adapted to extract the at least two sets of data from the at least two images of the at least one pattern represented consecutively in a temporal sequence.

Embodiment 35. A device according to one of the four preceding embodiments, the device further comprising a display configured to represent the at least one pattern by introducing the optically observable variation into the at least one pattern.

Embodiment 36. Apparatus according to the preceding embodiment, wherein the screen is selected from a monitor, a screen, and a display.

According to an advantageous characteristic, geometric parameters of the at least one optical lens are also extracted from the at least one image of the at least one pattern.

According to an advantageous development, the invention relates to a computer program for determining at least one optical parameter of at least one optical lens, the computer program being designed to carry out the following steps:

a) capture of at least one image of at least one pattern through at least one optical lens, and

b) determination of at least one optical parameter of the at least one optical lens from the at least one image of the at least one pattern,

according to this program from the at least one image of the at least one pattern having an optically observable variation, at least two data sets of characteristic values different from each other of the variation are extracted, and in that one determines at least one optical parameter of the at least one optical lens from the at least two sets of data.

According to an advantageous development, the invention relates to a method for determining at least one optical parameter of at least one spectacle lens of a pair of spectacles, the method comprising the following steps:

a) capture of at least one image of at least one pattern through one or both spectacle lenses of a pair of spectacles, and

b) determination of at least one optical parameter of one or both spectacle lenses of the pair of spectacles from the at least one image of the at least one pattern, and

from the at least one image of the at least one pattern having an optically observable variation, at least two data sets of characteristic values different from one another of the variation are extracted, and in that at least one optical parameter of the at least one eyeglass lens of the pair of eyeglasses from the at least two sets of data.

Brief description of figures

The invention is not limited to the embodiment examples. The exemplary embodiments are shown schematically in the figures. Identical reference numerals in each figure refer herein to elements which are identical or functionally identical or which correspond to each other from the point of view of their function. In detail :

illustrates a preferred embodiment of a device for determining at least one optical parameter of an optical lens,

the figure illustrates a provisional diagram of a preferred embodiment of a method according to the invention for determining at least one optical parameter of an optical lens,

illustrates a particularly preferred embodiment of the method for determining at least one optical parameter of an optical lens, and

illustrates another preferred embodiment of the method for determining at least one optical parameter of an optical lens with additional detection of the optical lens.

Examples of achievements

There schematically shows an example of a preferred embodiment of a device 110 for determining at least one optical parameter of an optical lens 112. It is possible here to determine an optical axis 114 with respect to the optical lens 112. The optical parameters determined by the device 110 respectively designate a characteristic quantity defined in more detail above of the optical lens 112, preferably of a sphero-cylindrical lens, in particular the maximum refractive index of each of the two main planes (meridians) and the cylinder thickness. The device 110 can be used here in particular to determine the optical parameters of one or both spectacle lenses 116 of a pair of spectacles 118. Other applications are nevertheless possible.

The example device 110 according to comprises a screen 120 arranged here preferentially as a monitor 122. The screen 120 is designed to represent a pattern 124 having a graphic structure having at least one spatially oriented period in which the structure of the pattern 124 is represented in a repetitive manner . As shown by way of example on the monitor 122 in the , the pattern 124 can comprise a pattern in strips 126 comprising a plurality of strips arranged parallel to one another on the monitor 122. Other types of patterns 124 are nevertheless possible, in particular a superposition of several patterns in strips 126 (cf. 3 and 4), circle patterns or dot patterns.

The screen 120 is further designed to represent an optically observable variation of the pattern 124, the pattern 124 being able to admit at least two different characteristic values from each other for the variation. With the pattern 124 present here, there is for example such a spatial modulation of the pattern 124, following which the pattern in bands 126 in a first partial zone 128 presents as corresponding characteristic value a first interval between bands 130, in a second partial zone 132 has as corresponding characteristic value a second interval between bands 134 and in a third partial zone 136 has as corresponding characteristic value a third interval between bands 138. As mentioned above, other types of variation of pattern 124 are nevertheless possible alternatively or in addition, in particular a chromatic modulation evoked in more detail in figures 3 and 4 below, as well as a temporal modulation which can also be designated by "frequency modulation".

Device 110 further includes camera 140, which is adapted to capture one or more images (not shown) of pattern 124 and, accordingly, is correspondingly aligned to pattern 124. Camera 140 may preferably be a video 142 which allows the capture of successions of images. Other embodiments of the camera 140 are nevertheless possible.

As further shown in the , the optical lens 112 is spatially disposed for the purpose of determining the optical parameter, in a location 144 located between the screen 120 and the camera 140. The location 144, as shown in , can be located as precisely as possible in the middle between the screen 120 and the camera 140; another arrangement of the optical lens 112 relative to the screen 120 and to the camera 140 is nevertheless possible, in particular at a location 144 closer to the screen 120 than to the camera 140. In particular, for maximum magnification or minimal, or minimal shrinkage, placing the optical lens 112 as precisely as possible in the middle between the screen 120 and the camera 140 can be advantageous; however, changing the arrangement of the optical lens 112 during the measurement may have an advantage in finding this minimum or maximum by comparing the magnification or shrinkage in each image.

Due to the presence of optical lens 112 at location 144 between screen 120 and camera 140, camera 140 captures an image of pattern 124, in which pattern 124 is captured in a modified manner depending on the layout. of the optical lens 112 between the screen 120 and the camera 140 and according to the optical parameters of the optical lens 112. As already shown above, this modification manifests itself in particular by a magnification of the pattern 124 on the image compared to the representation of pattern 124 on screen 120.

As further shown by the , both the screen 120 and the camera 140 can be connected respectively by a wired or wireless link 146 to an evaluation unit 150, preferably inserted in a housing 148. Otherwise, the evaluation unit 150 can nevertheless also be introduced into a common casing with the screen 120 or the camera 140. Other types of embodiment are nevertheless possible. The evaluation unit 150 is designed to perform the desired determination of the optical parameter of the optical lens 112 on the basis of the image of the pattern 124. of images that the camera 140 has captured and transmitted to the evaluation unit 150 to determine one or more optical parameters of the optical lens 112. In addition, results of the determination of the optical parameters of the optical lens 112 can be made available to the user or a third party, in particular an optician or an oculist, for example by means of a monitor 152, which can also be connected to the evaluation unit 150 at the means of a wired or wireless link 146. In addition, a keyboard 154 can be provided, in particular to control both the screen 120 and the camera 140. Other embodiments of the evaluation unit 150 are nevertheless possible.

According to the invention, the evaluation unit 150 is designed to extract from the image of the pattern 124 exhibiting, as described above in more detail, an optically observable variation, at least two data sets of different characteristic values between them of the variation. In the realization according to , which shows by way of example a spatial modulation of the pattern 124, it is possible to extract from the captured image the three partial zones 128, 132, 136 of the pattern 124 delimited with respect to each other and which are represented there by means of an image processing in the form of three sets of data, the corresponding characteristic value of the variation, influenced by the optical lens 112 being respectively able to be determined. Here, the analysis of each partial zone 128, 132, 136 of the pattern 124 can preferably be done by processing in parallel, which makes it possible to significantly reduce the processing time.

According to the invention, the evaluation unit 150 is also designed to determine at least one optical parameter of the optical lens 112 from the at least two sets of data. As specified in more detail above, the presence of the optical lens 112 at the location 144 between the screen 120 and the camera 140, results for this purpose in a magnification of the pattern 124 which the camera can capture. To determine the magnification from the image of the pattern 124, one can undertake known methods, in particular a 1D Fourier transform of a profile along a direction in the image, a 2D Fourier transform of a partial area of the image or an adaptation (fitting) of geometric shapes. To determine the at least one optical parameter of the optical lens 112, in particular the refractive index of a sphero-cylindrical lens, those skilled in the art can evaluate the magnification of the pattern detected by measurement techniques by the optical lens 112 by methods known to those skilled in the art by means of the evaluation unit 150.

Contrary to the state of the art, as described in particular in WO 2016/181310 Al, to determine the at least one optical parameter of the optical lens 112, it is possible to dispense with a displacement of the screen 120 and/or of the camera 140, since a single image is already sufficient to be able to perform the desired determination of the at least one optical parameter of the optical lens 112 from the at least two sets of data which are extracted therefrom.

There schematically shows a provisional diagram of a preferred embodiment of a method according to the invention 210 for determining at least one optical parameter of an optical lens.

In a representation step 212, before or during step a), the representation of the pattern 124 on the screen 120 is carried out for this purpose, the pattern 124 having an optically observable variation defined by at least two different characteristic values the one from the other.

In an image capture step 214 takes place according to step a) the capture of an image of the pattern 124 created during the representation step 212 presenting the optically observable variation, through an optical lens 112.

In an extraction step 216 takes place according to step b) the extraction, from the image of the pattern 124 created during the image capture step 214, of at least two sets of data values characteristics different from each other, which are assigned to the optically observable variation of the pattern 124 in the image.

In a determination step 218 takes place, also according to step b), the determination of the at least one optical parameter of the optical lens 112 from the image of the pattern 124, the at least one optical parameter of the optical lens 112 being determined from the at least two sets of data created during the extraction step 216.

In this way, it is possible to determine at least two optical parameters 220, 220',... different from each other of the optical lens 112, preferably simultaneously, preferably in a time interval of maximum 1 s, particularly preferentially of maximum 0.05 s, in particular of maximum 0.004 s, which makes it possible to particularly reduce the time required for this. In addition, a simultaneous determination of at least two sets of data excludes undesirable modifications of parameters, for example a change in position and/or orientation of the optical lens 112 and/or of the screen 120 and/or of the camera 140. The determination of at least two data sets, respectively with different variations of the pattern 124, can additionally lead to an increase in the accuracy of the measurement results.

There shows a particularly preferred embodiment of the method for determining at least one optical parameter of an optical lens 112.

According to , three partial patterns 222, 224, 226, different from each other, each representing a pattern in bands 126 of different orientations, are represented respectively in another color channel of the screen 120 for precisely a characteristic value in the color respective color channel. In doing so, each partial pattern 222, 224, 226 is correlated to exactly one color. In addition to the striped pattern 126, each of the partial patterns 222, 224, 226 has several markings 228, 230, 232. According to markings 228, 230, 232, the partial patterns 222, 224, 226, as shown in , are layered together to give pattern 124.

There shows the image 234 of the pattern 124 captured with the camera 140, the presence represented schematically in the of the optical lens 112 at the location 144 between the screen 120 and the camera 140 has the effect that the camera 140 captures an image 234 of the pattern 124 modified with respect to the representation of the pattern 124 on the screen 120. As already represented above, this modification manifests itself in particular by an enlargement of the pattern 124 on the image 234 compared to the representation of the pattern 124 on the screen 120.

As depicted in the , after the capture of the image 234 with the camera 140, it is possible to extract from the image 234 modified partial patterns 236, 238, 240 respectively in the form of data sets 242, 244, 246 by means of corresponding color channels of the camera 140, then they can be processed independently of each other. Because each partial pattern 222, 224, 226 is precisely correlated to a characteristic value of pattern 124 and furthermore each partial pattern 222, 224, 226 is precisely correlated to a color, each data set extracted from the image 234 in the respective color channel is also correlated to the characteristic value of the pattern 124. By this, the modified partial patterns 236, 238, 240 represented in each color channel are analyzed independently of each other.

There shows another preferred embodiment of the method for determining at least one optical parameter of an optical lens 112 with additional detection of the optical lens 112. To do this, as shown in the , one can extract from the image 234 captured by the camera 140 represented in the according to the realization of the the two modified partial patterns 236, 240 respectively as individual data sets 242, 246 of the corresponding color channels of the camera 140 from the image 234, then they can be processed independently of each other.

Additionally, another screen 120 color channel is saved when displaying the partial pattern, so that no partial pattern is produced on that other screen 120 color channel. of the image 234 by the camera 140, a corresponding color channel of the camera 140 has no partial pattern or at most only one partial pattern of substantially reduced intensity due to interference between different color channels of the camera 140 Thanks to this, it is possible to use the data set 244 extracted from this color channel of the camera 140 in a particularly preferential way to determine, by image processing, geometric data of the optical lens 112 or of a mount 248 glasses containing the glasses lens 116, without this determination being hampered by a disturbing partial pattern in the background, which can have a disturbing effect, in particular in the event of highlighting the edges of the frame 248 of glasses are. In the captured image 234, a detection of the area occupied by the optical lens 112 is thus carried out more precisely, whereby, for example, a subdivision of the optical lens 112 into different partial areas is facilitated, for example for the analysis multifocal lenses.

NOMENCLATURE OF THE MAIN ELEMENTS

110 Device for determining at least one optical parameter of an optical lens

112 Optical lens

114 Optical axis

116 Spectacle lens

118 Pair of glasses

120 Screen

122 Monitor

124 Pattern

126 Banded pattern

128 First partial area

130 First interval between bands

132 Second partial zone

134 Second gap between bands

136 Partial Third Zone

138 Third interval between bands

140 Camera

142 Video camera

144 Place

146 Binding

148 Carter

150 Assessment unit

152 Monitor

154 Keyboard

210 Method for determining at least one optical parameter of an optical lens

212 Representation step

214 Image capture step

216 Extraction step

218 Determination step

220, 220’, … Optical parameter

222 Partial pattern

224 Partial pattern

226 Partial pattern

228 Marking

230 Marking

232 Marking

234 Picture

236 Partial Pattern

238 Partial Pattern

240 Partial pattern

242 Dataset

244 Dataset

246 Dataset

248 Glasses frame

Claims (15)

Method (210) for determining at least one optical parameter (220, 220', …) of at least one optical lens (112), the method (210) comprising the following steps:
a) capturing at least one image (234) of at least one pattern (124) through at least one optical lens (112), and
b) determination of at least one optical parameter (220, 220, 220') of the at least one optical lens (112) from the at least one image (234) of the at least one pattern (124 ),
characterized in that from the at least one image (234) of the at least one pattern (124) exhibiting an optically observable variation, at least two sets of data (242, 244, 246) of values mutually different characteristics of the variation, and in that at least one optical parameter (220, 220', ...) of the at least one optical lens (112) is determined from the at least two sets of data (242 , 244, 246). Method (210) according to the preceding claim, characterized in that the at least two sets of data (242, 244, 246) are extracted simultaneously from the at least one image (234) of the at least one pattern (124) . Method (210) according to one of the preceding claims, characterized in that each characteristic value of the variation of the at least one pattern (124) is correlated with a modulation of the at least one pattern (124), the variation being selected from a chromatic, spatial or temporal modulation of the at least one pattern (124). Method (210) according to the preceding claim, characterized in that the chromatic modulation of the at least one pattern (124) is carried out by superimposing the at least one pattern (124) from at least two patterns partials (228, 230, 232) each having a distinct color, and in that the at least two partial patterns (236, 238, 240) are extracted from the at least one image (234). Method (210) according to one of the two preceding claims, characterized in that the spatial modulation of the at least one pattern (124) is carried out by at least one difference of the at least one pattern (124) in at at least two partial areas (128, 132, 136) different from each other of the at least one pattern (124) and in that the at least two partial areas (128, 132, 136) of the at at least one pattern (124) are extracted from the at least one image (234). Method (210) according to one of the three preceding claims, characterized in that the temporal modulation of the at least one pattern (124) is carried out by at least two patterns (124) represented according to a temporal succession, the at least two sets of data being extracted from the at least two images (234) of the patterns (124) represented consecutively according to a temporal succession. Method (210) according to one of the preceding claims, characterized in that the at least one pattern (124) is represented without any relative movement of the at least one pattern with respect to the at least one optical lens (112) or a camera (140). Method (210) according to one of the preceding claims, characterized in that the relative differences between the at least two sets of data (242, 244, 246) of the mutually different characteristic values of the variation are taken into account. Method (210) according to one of the preceding claims, characterized in that the at least one pattern (124) is known, or in that the method (210) is carried out at least twice with the same pattern (124) or another pattern (124). Method (210) according to the preceding claim, characterized in that the geometric parameters of the at least one optical lens (112) are also extracted from the at least one image (234) of the at least one pattern (114). Computer program for determining at least one optical parameter (220, 220', ...) of at least one optical lens (112), the computer program being designed to carry out the following steps:
a) capturing at least one image (234) of at least one pattern (124) through at least one optical lens (112), and
b) determination of at least one optical parameter (220, 220', ...) of the at least one optical lens (112) from the at least one image (234) of the at least one pattern (124 ),
characterized in that from the at least one image (234) of the at least one pattern (124) exhibiting an optically observable variation, at least two sets of data (242, 244, 246) of values mutually different characteristics of the variation, and in that at least one optical parameter (220, 220', ...) of the at least one optical lens (112) is determined from the at least two sets of data (242 , 244, 246). Method for determining at least one optical parameter (220, 220', ...) of at least one spectacle lens of a pair of glasses (118), the method comprising the following steps:
a) capturing at least one image (234) of at least one pattern (124) through one or both spectacle lenses (116) of a pair of spectacles (118), and
b) determination of at least one optical parameter (220, 220', ...) of one or both spectacle lenses (116) of the pair of spectacles (118) from the at least one image (234 ) of the at least one pattern (124),
characterized in that from the at least one image (234) of the at least one pattern (124) exhibiting an optically observable variation, at least two sets of data (242, 244, 246) of values mutually different characteristics of the variation, and in that at least one optical parameter (220, 220', ...) of the at least one spectacle lens (116) of the pair of spectacles (118) is determined from the at least two data sets (242, 244, 246). Device (110) for determining at least one optical parameter (220, 220', ...) of at least one optical lens (112), the device (110) comprising:
- a camera (140) designed to capture at least one image (234) of at least one pattern (124) through at least one optical lens (112), and
- an evaluation unit (150) designed to determine at least one optical parameter (220, 220', …) of the at least one optical lens (112) from the at least one image (234) of the 'at least one pattern (124),
characterized in that the evaluation unit (150) is further adapted to extract from the at least one image (234) of the at least one pattern (124) having an optically observable variation, at least two sets of data (242, 244, 246) of mutually different characteristic values of the variation, and to determine at least one optical parameter (220, 220', ...) of the at least one optical lens (112) from the at least two data sets (242, 244, 246). Device (110) according to the preceding claim, characterized in that the evaluation unit (150) is designed to extract the at least two sets of data (242, 244, 246),
- of respectively a respectively different color channel of the camera (140),
- of respectively a partial area (128, 132, 136) of the at least one image (234), or
- at least two images (234) of the at least one pattern (124) prepared consecutively according to a temporal succession. Device (110) according to one of the two preceding claims, characterized in that the device (110) further comprises:
- a screen (120) designed to represent the at least one pattern (124) by introducing the optically observable variation in the at least one pattern (124).