Treatment device for eye treatment, procedure, computer program and computer-readable medium

Abstract

Treatment device (1) for an eye treatment, comprising at least: - at least one laser beam source (2), designed to emit laser pulses (3), - at least one beam emission device (4) which is configured to direct the respective laser pulses (3) with a predetermined laser pulse cross-sectional profile (5) to respective impact positions (6) in a treatment area (7) of a predetermined treatment volume (8) of an eye (9) to be treated, - a control device (10) configured to determine coordinates (13) of the respective impact positions (6) in the treatment area (7) according to at least two predetermined coordinate determination methods for the predetermined treatment volume (8) and the predetermined laser pulse cross-sectional profile (5), wherein the at least two predetermined coordinate determination methods describe respective patterns and / or algorithms which specify a determination of the coordinates (13) of the respective impact positions (6) for the predetermined treatment volume (8), - to determine, according to a predetermined roughness determination method, the respective treatment roughnesses of the treatment volume (8) to be expected for the given treatment volume (8), which depend on the coordinate determination method, for the at least two predetermined coordinate determination methods, - to determine the predetermined coordinate determination method of a smallest expected treatment roughness dependent on the coordinate determination method as the coordinate determination method to be set, and - to set the coordinates (13) of the respective impact positions (6) according to the coordinate determination method to be set in the at least one radiation exit device (4).

Description

[0001] The present invention relates to a treatment device for eye treatment according to the features of the preamble of claim 1. The invention also relates to a method for controlling the treatment device according to the features of the preamble of claim 12, a computer program according to the features of the preamble of claim 14, and a computer-readable medium according to the features of the preamble of claim 15.

[0002] Treatment devices and methods for controlling ophthalmic lasers to correct optical refractive errors and / or pathologically or abnormally altered areas of the cornea are known in the prior art. For example, a pulsed laser and a beam focusing device can be configured such that laser pulses in a focus located within the organic tissue cause photodisruption and / or photoablation to remove tissue, in particular a tissue lenticle, from the cornea.

[0003] When performing ablation procedures, it is desirable to minimize the surface roughness of the areas of a volume ablated from the tissue. The surface roughness of a treatment volume ablated using laser pulses is influenced by several parameters of the laser treatment. The surface roughness depends, for example, on a laser pulse cross-sectional profile of the laser pulses used to ablate the treatment volume. The laser pulse cross-sectional profile describes a radial intensity distribution of the laser pulse irradiation, emanating from a center. Furthermore, the surface roughness depends on a pattern that forms the coordinates of the impact points of the laser pulses in an ablation area of ​​the ablation volume.

[0004] CN 1528256 A discloses a method and device for laser pulse ablation of corneal tissue using layer scanning. In the method, the device generates laser pulses, and the corneal tissue is scanned at high speed with the laser pulses in two directions to reach specific points on the corneal tissue within a preset action area according to an algorithm set by a program.

[0005] In the publication Verma, S., Hesser, J., & Arba-Mosquera, S. (2017). Optimum laser beam characteristics for achieving smoother ablations in laser vision correction. Investigative ophthalmology & visual science, 58(4), 2021-2037., a simulation model was designed for simulating a shot-by-shot ablation process. The effects of laser beam properties such as super-Gaussian order, cutoff radius, spot geometry, spot overlap, and grating geometry were tested for their influence on ablation smoothness.

[0006] DE 10 2008 035 898 A1 describes a device and a method for speckle reduction in the field of laser applications.

[0007] EP 3 235 078 B1 describes a laser sensor module for time-of-flight measurements.

[0008] US 2021 / 0 038 428 A1 describes a system for treating an eye. The system comprises a laser light source that provides photoactivating light. The system includes a scanning system for receiving the photoactivating light as a laser beam and moving the laser beam across a cornea treated with a cross-linking agent.

[0009] The known methods allow for a reduction in the surface roughness of surfaces for certain treatment methods. However, the surface roughness of the surfaces of ablated treatment volumes continues to increase with increasing ablation depth.

[0010] The invention is based on the object of providing a treatment device which enables removal of treatment volumes with a reduced surface roughness.

[0011] This object is achieved by the treatment device according to the invention according to the features of claim 1, the method according to the invention according to the features of claim 12, the computer program according to the invention according to the features of claim 14, and the computer-readable medium according to the invention according to the features of claim 15. Advantageous embodiments with expedient further developments of the invention are specified in the respective subclaims, wherein advantageous embodiments of each aspect of the invention are to be regarded as advantageous embodiments of the respective other aspects of the invention.

[0012] A first aspect of the invention relates to a treatment device for eye treatment. It is provided that the treatment device has at least one laser beam source configured to emit laser pulses. The treatment device has at least one beam exit device configured to direct the respective laser pulses with a predetermined laser pulse cross-sectional profile to respective impact positions in a treatment area of ​​a predetermined treatment volume of an eye to be treated.

[0013] The treatment device comprises a control device configured to determine the coordinates of the respective impact positions of the laser pulses in the treatment area according to at least two predetermined coordinate determination methods for the specified treatment volume and the predetermined laser pulse cross-sectional profile. In other words, the control device is configured to provide the coordinates to which the respective laser pulses are guided in the treatment area of ​​the specified treatment volume in order to ablate the specified treatment volume. The control device is configured to determine the coordinates according to the at least two coordinate determination methods depending on the specified laser pulse cross-sectional profile.The coordinate determination methods are designed to guide the control device to provide the coordinates of the respective impact positions of the laser pulses in the treatment area for the specified laser pulse cross-sectional profile. The predetermined coordinate determination methods describe respective patterns and / or algorithms that specify a definition of the coordinates for the treatment volume. The coordinates determined by the respective coordinate determination methods can differ from one another, so that at least two respective coordinate sets can be provided by the at least two coordinate determination methods.

[0014] The control device is configured to determine, according to a predetermined roughness determination method for the at least two coordinate determination methods, the respective treatment roughnesses of the treatment volume to be expected for the specified treatment volume, depending on the coordinate determination method. In other words, the control device is configured to determine, according to the predetermined roughness determination method, for the at least two sets of coordinates determined by the respective coordinate determination methods, which treatment roughness the treatment volume has after the laser pulses have been directed to the coordinates of the respective impact positions in order to ablate the treatment volume.The control device can, for example, be configured to perform simulations as the predetermined roughness determination method, which simulate the removal of the treatment volume and a resulting surface of the treatment volume. The treatment roughness can be specified, for example, as a mean roughness value, root mean square roughness, or averaged roughness depth of the surfaces comprising the treatment volume.

[0015] The control device is configured to determine the coordinate determination method of a smallest expected treatment roughness dependent on the coordinate determination method as the coordinate determination method to be set and to set the coordinates of the respective impact positions according to the coordinate determination method to be set in the at least one beam exit device. In other words, the control device is configured to compare the expected treatment roughnesses dependent on the coordinate determination method, which result from the coordinate sets of the respective coordinate determination methods, with one another in order to determine which of the coordinate determination methods leads to coordinates that result in a minimum treatment roughness of the treatment volume.The control device is configured to set the coordinates of the coordinate determination method of the smallest expected treatment roughness dependent on the coordinate determination method in the at least one beam exit device before the eye treatment in order to guide the laser pulses to the associated coordinates.

[0016] The control device is configured to carry out the roughness determination method before performing the ablation method. In other words, it is provided that, before performing the eye treatment, the control device determines which of the at least two coordinate determination methods enables ablation of the treatment volume with the lowest surface roughness. The control device is configured to set the coordinates determined according to the coordinate determination method to be set in the beam exit device so that the laser pulses are directed to the coordinates determined by means of the coordinate determination method to be set during the eye treatment. The invention provides the advantage that, before performing the eye treatment, the appropriate coordinate determination method to be set is determined by means of a calculation or simulation.

[0017] The invention also includes further developments which result in additional advantages.

[0018] A further development of the invention provides that the control device is configured to determine, prior to the eye treatment, the respective profile-dependent treatment roughnesses of the treatment volume to be expected for the specified treatment volume for at least two potential laser pulse cross-sectional profiles of the laser pulses, according to a predetermined profile determination method. In other words, the control device determines, according to the predetermined profile determination method, which respective profile-dependent treatment roughness of the treatment volume the at least two potential laser pulse cross-sectional profiles of the laser pulses will lead to.The control device is configured to determine the laser pulse cross-sectional profile of a smallest expected profile-dependent treatment roughness as the predetermined laser pulse cross-sectional profile of the laser pulses and to adjust the predetermined laser pulse cross-sectional profile in the at least one beam exit device. In other words, the laser pulse cross-sectional profile of the laser pulses is determined, which leads to a minimum profile-dependent treatment roughness of the treatment volume. The profile-dependent treatment roughness can be determined, for example, through simulations. The development of the invention results in the advantage that, by selecting the most suitable laser pulse cross-sectional profile, a portion of the surface roughness attributable to the laser pulse cross-sectional profile can be reduced.The determination of the specified laser pulse cross-sectional profile can be carried out before the selection of the coordinate determination method, so that the appropriate coordinate determination method can be carried out for the intended laser pulse cross-sectional profile for which a minimum profile-dependent treatment roughness of the treatment volume is determined.

[0019] A further development of the invention provides that the control device is configured to determine, prior to the eye treatment, respective varied coordinate sets, comprising varied coordinates of the respective impact positions from the coordinates according to at least two predetermined jitter methods, wherein the varied coordinates of the varied coordinate sets are shifted by respective jitter shifts relative to the coordinates of the coordinate sets of the respective impact positions in the treatment area. The control device is configured to determine, according to a predetermined jitter roughness determination method, expected jitter-dependent treatment roughnesses of the treatment volume for the respective varied coordinate sets and to replace the coordinates with the varied coordinates of the varied coordinate set of a smallest expected jitter-dependent treatment roughness.In other words, it is provided that the control device is configured to carry out the at least two jitter methods. The at least two jitter methods can specify respective jitter shifts of the coordinates of the respective impact positions. The jitter shifts can lie flat in the treatment area and include periodic and / or random components. As a result, the varied coordinates are shifted from the original coordinates of the impact positions by the respective jitter shifts in the treatment area. The control device is configured to evaluate the varied coordinate sets generated by the respective jitter methods, which comprise the varied coordinates, according to the predetermined jitter roughness determination method, wherein respective jitter-dependent treatment roughnesses are determined for the respective varied coordinate sets.The control device is configured to determine which of the varied coordinate sets leads to a minimum jitter-dependent treatment roughness of the treatment volume. The control device is configured to apply the jitter method that leads to the minimum jitter-dependent treatment roughness to perform the eye treatment method. At least one of the jitter methods can provide for no jitter shifts. The control device can thereby determine whether a variation of the coordinates influences the roughness and refrain from varying the coordinates if the jitter method that does not provide for jitter shifts leads to the minimum jitter-dependent treatment roughness of the treatment volume.

[0020] A further development of the invention provides that the at least two predetermined coordinate determination methods comprise at least one predefined dithering method. The dithering method can, for example, specify a respective dithering matrix. The dithering matrix is ​​also known as an index matrix, Bayer matrix, or threshold map.

[0021] A further development of the invention provides that the at least two predetermined coordinate determination methods comprise at least one of the following predetermined dithering methods: Floyd-Steinberg, thresholding, random dithering, ordered dithering, Bayer matrix, minimized average error, Stucki dithering, Burkes dithering, Sierra dithering, two-row Sierra, Filter Lite, Atkinson dithering, or gradient-based error-diffusion dithering. In other words, the control device is configured to apply at least one of the aforementioned dithering methods as a coordinate determination method for determining the coordinates of the respective impact positions of the laser pulses in the treatment area.

[0022] A further development of the invention provides that the at least two potential laser pulse cross-sectional profiles comprise at least one Gaussian cross-sectional profile. In other words, at least one of the laser pulse cross-sectional profiles is a laser pulse cross-sectional profile that describes a Gaussian distribution of the intensity of the laser pulse across the cross section. In other words, the control device is configured to control the beam exit device to generate a laser pulse having the Gaussian cross-sectional profile.

[0023] A further development of the invention provides that the at least two potential laser pulse cross-sectional profiles comprise at least one pinhole cross-sectional profile. In other words, it is provided that at least one of the two laser pulse cross-sectional profiles is clipped to a predetermined pinhole width. In other words, it is provided that in at least one laser pulse cross-sectional profile, a profile width is limited to a pinhole width. In this case, a course of the profile can have an intensity value of 0 from a predetermined distance. In further other words, the control device is configured to control the beam exit device to generate a laser pulse which has a laser pulse cross-sectional profile that is limited to a pinhole width at least in one direction.

[0024] A further development of the invention provides that the at least two potential laser pulse cross-sectional profiles have different half-widths. In other words, the at least two laser pulse cross-sectional profiles differ from one another in their half-widths. In other words, the control device is configured to control the beam exit device to emit laser pulses whose laser pulse cross-sectional profiles differ from one another in their half-widths.

[0025] A further development of the invention provides that the at least two potential laser pulse cross-sectional profiles differ from one another in their maximum radiant exposures. In other words, the at least two laser pulse cross-sectional profiles have different maximum radiant exposures. In further other words, the radiant exposures of the at least two laser pulse cross-sectional profiles differ from one another in their maximum values.

[0026] A further development of the invention provides that the at least two jitter methods comprise at least one random-based jitter method. In other words, at least one of the jitter methods is a random-based jitter method. The random-based jitter method can also be referred to as random jitter. The random-based jitter method is characterized in that the generated jitter shifts exhibit a normal distribution. In other words, the control device is configured to apply at least one random-based jitter method to generate the jitter shifts of the coordinates of the respective impact positions of the laser pulses in the treatment area.

[0027] A further development of the invention provides that the at least two jitter methods comprise at least one deterministic jitter method. In other words, at least one of the jitter methods is a deterministic jitter method for generating deterministic jitter shifts. The deterministic jitter method can, for example, generate jitter shifts that include a periodic component. In other words, the control device is configured to apply at least one deterministic jitter method to generate the jitter shifts of the coordinates of the respective impact positions of the laser pulses in the treatment area.

[0028] A second aspect of the invention relates to a method for controlling a treatment device by a control device. The control device is configured to carry out the method for controlling a treatment device. The control device can be designed, for example, as a control chip, control unit, or user program (“app”). The control device can preferably have a processor device and / or a data memory. A processor device is understood to be a device or device component for electronic data processing. The processor device can, for example, have at least one microcontroller and / or at least one microprocessor. A computer program for carrying out the method according to the invention can preferably be stored on the optional data memory and / or a computer-readable medium.The computer program can then be designed, when executed by the processor device, to cause the control device to carry out one of the above-described embodiments of one or both of the methods according to the invention.

[0029] The control device is configured to control the treatment device. The method comprises at least the following steps.

[0030] In one step, before carrying out the treatment, coordinates of respective impact positions in a treatment area for a predetermined treatment volume and a predetermined laser pulse cross-sectional profile are determined according to a predetermined coordinate determination method. In other words, the control device is intended to determine the coordinates which the respective impact positions of the laser pulse in the treatment area for the predetermined treatment volume have. The coordinates are determined taking into account the predetermined laser pulse cross-sectional profile which the laser pulses have. The coordinates of the respective impact positions are determined according to the predetermined coordinate determination method, which, for example, specifies a dithering matrix in order to determine the coordinates of the impact positions of the laser pulses in the treatment area.

[0031] In a further step, the respective treatment roughnesses of the treatment volume to be expected for the given treatment volume are determined according to a predetermined roughness determination method for the at least two coordinate determination methods.

[0032] Subsequently, the coordinate determination method for the smallest expected treatment roughness dependent on the coordinate determination method is determined as the predetermined coordinate determination method. In other words, the coordinate determination method that generates coordinates that lead to the smallest expected treatment roughness dependent on the coordinate determination method is determined.

[0033] In a further step, the beam exit device is controlled by the control device. In other words, the beam exit device is controlled by the control device, which directs the laser pulses to the respective impact positions in the treatment area. The coordinates in the beam exit device can be adjusted sequentially, so that the beam exit device can be adjusted to the respective impact positions one after the respective pulses are emitted.

[0034] Further features and their advantages can be found in the descriptions of the first aspect of the invention, wherein advantageous embodiments of each aspect of the invention are to be regarded as advantageous embodiments of the other aspect of the invention.

[0035] A further development of the invention provides that the method comprises at least the following steps: Determining the respective profile-dependent treatment roughness of the treatment volume to be expected for the specified treatment volume for the at least two potential laser pulse cross-sectional profiles according to the predetermined profile determination method by the control device. In other words, it is provided that, before carrying out the treatment method, the control device determines which profile-dependent treatment roughness the use of the respective at least two laser pulse cross-sectional profiles of the laser pulses leads to. In a further step, it is provided that the control device determines the laser pulse cross-sectional profile for which the smallest expected profile-dependent treatment roughness results.This laser pulse cross-sectional profile is set as the predetermined laser pulse cross-sectional profile for the treatment procedure. In other words, the laser pulse cross-sectional profile that results in the minimum profile-dependent treatment roughness is determined for the treatment and set in the beam output device.

[0036] A further development of the invention provides that the method comprises at least the following steps: Determining respective varied coordinate sets, comprising varied coordinates of the coordinates according to at least two jitter methods by the control device, wherein the varied coordinates of the varied coordinate sets are shifted by respective jitter shifts in the treatment area compared to the coordinates in the treatment area. In other words, it is provided that before carrying out the treatment method, the coordinates of the coordinate set are varied according to the at least two jitter methods in order to generate the varied coordinates of the varied coordinate sets. The respective jitter-dependent treatment roughnesses of the treatment volume to be expected for the predetermined treatment volume are determined for the coordinate sets according to the predetermined jitter roughness determination method.In other words, the jitter-dependent treatment roughnesses are determined for the respective varied coordinate sets. This allows us to determine which jitter-dependent treatment roughness would result from applying the respective jitter methods. In a further step, the coordinates are replaced by the varied coordinates of the coordinate set of the smallest expected jitter-dependent treatment roughness.

[0037] A third aspect of the invention relates to a computer program comprising instructions which cause a control device to carry out the method steps according to the second aspect of the invention.

[0038] Further features and their advantages can be found in the descriptions of the first and second aspects of the invention, wherein advantageous embodiments of each aspect of the invention are to be regarded as advantageous embodiments of the other aspect of the invention.

[0039] A fourth aspect of the invention relates to a computer-readable medium on which the computer program according to the third aspect of the invention is stored.

[0040] Further features and their advantages can be found in the descriptions of the first, second and third aspects of the invention, wherein advantageous embodiments of each aspect of the invention are to be regarded as advantageous embodiments of the respective other aspect of the invention.

[0041] Further features of the invention emerge from the claims, the figures and the description of the figures. The features and combinations of features mentioned above in the description, as well as the features and combinations of features mentioned below in the description of the figures and / or shown alone in the figures can be used not only in the respective combination specified, but also in other combinations without departing from the scope of the invention. Thus, embodiments are to be regarded as encompassed and disclosed by the invention that are not explicitly shown and explained in the figures, but which emerge and can be produced by separate combinations of features from the explained embodiments. Embodiments and combinations of features are also to be regarded as disclosed that therefore do not have all the features of an originally formulated independent claim.Furthermore, embodiments and combinations of features are to be considered disclosed, in particular by the embodiments presented above, which go beyond or deviate from the combinations of features presented in the claims. This shows: Fig. 1 a schematic representation of a treatment device for an eye treatment; Fig. 2 a schematic representation of two patterns; Fig. 3 a schematic representation of a shift of the coordinates by jitter shifts; Fig. 4 a schematic representation of possible laser pulse cross-section profiles; and Fig. 5 a schematic representation of a sequence of a method for controlling the treatment device.

[0042] Fig. 1 shows a schematic representation of a treatment device for eye treatment. The treatment device 1 has at least one laser beam source 2, which can be configured to emit laser pulses 3. The treatment device 1 can additionally have at least one beam exit device 4, which can be configured to guide the respective laser pulses 3 with a predetermined laser pulse cross-sectional profile 5 to respective impact positions 6 on a treatment area 7 of a predetermined treatment volume 8 of an eye 9 to be treated. The treatment device 1 can have a control device 10, which can be configured to control the beam exit device 4 and the laser beam source 2 to ablate the treatment volume 8.It can be provided that the removal of the treatment volume 8 preferably takes place in such a way that side surfaces 11 of the treatment volume 8 and a base surface 12 of the treatment volume 8 have a minimal surface roughness. The surface roughness of the side surfaces 11 of the treatment volume 8 and the surface roughness of the base surface 12 of the treatment volume 8 can be combined to form the treatment roughness of the treatment volume 8. The treatment roughness of the treatment volume 8 can depend on several factors. In order to minimize the overall treatment roughness of the treatment volume 8, it may therefore be necessary to individually optimize the individual parameters that influence the surface roughness.

[0043] The surface roughness can depend on the laser pulse cross-sectional profile 5 of the laser pulses 3. By selecting the predetermined laser pulse cross-sectional profile 5, it is thus possible to reduce the treatment roughness. The control device 10 can be configured to determine, prior to the eye treatment, the profile-dependent treatment roughnesses of the treatment volume 8 to be expected for the predetermined treatment volume 8 for at least two potential laser pulse cross-sectional profiles 5 of the laser pulses 3, using a predetermined profile determination method. In other words, at least two laser pulse cross-sectional profiles 5 can be stored in the control device 10, which can comprise the laser pulses 3 generated by the treatment device 1. The laser pulse cross-sectional profiles 5 can, for example, comprise a Gaussian profile.The laser pulse cross-sectional profiles 5 can describe an intensity distribution of the respective laser pulses 3 over a radius of the laser pulses 3. Depending on the laser pulse cross-sectional profiles 5 of the respective laser pulses 3, respective treatment roughnesses of the treatment volume 8 can result. The control device 10 can be configured to determine, according to the predetermined profile determination method for the at least two potential laser pulse cross-sectional profiles 5 of the laser pulses 3, respective profile-dependent treatment roughnesses of the treatment volume 8 to be expected for the specified treatment volume 8.In other words, the control device 10 can be configured to determine, according to the predetermined profile determination method for the at least two potential laser pulse cross-sectional profiles 5, the respective profile-dependent treatment roughnesses of the treatment volume 8 that would result from selecting the respective laser pulse cross-sectional profile 5. The control device 10 can be configured to determine the laser pulse cross-sectional profile 5 of the smallest expected profile-dependent treatment roughness as the predetermined laser pulse cross-sectional profile 5 and to adjust the predetermined laser pulse cross-sectional profile 5 in the at least one beam exit device 4 during the treatment process.

[0044] Possible laser pulse cross-section profiles 5 are shown in Fig. 4. These can differ from one another in their maximum irradiation 14, their profiles, and / or their half-widths 18. Provision can be made for the laser pulse cross-sectional profiles 5 to be laterally restricted by an aperture. This allows edge regions that lie outside a selected distance from the center to be removed. Consequently, the laser pulse cross-sectional profiles 5 can be restricted to a pinhole width 19.

[0045] The control device 10 can be configured to determine the coordinates 13 of the respective impact positions 6 of the laser pulses 3 in the treatment area 7 according to at least two predetermined coordinate determination methods for the predefined treatment volume 8 and the predetermined laser pulse cross-sectional profile 5. The at least two coordinate determination methods can comprise matrices which can enable the determination of the coordinates 13 of the respective impact positions 6 in the treatment area 7. The coordinate determination methods can comprise, for example, the following methods: Floyd-Steinberg, thresholding, random dithering, ordered dithering, Bayer matrix, minimized average error, Stucki dithering, Burkes dithering, Sierra dithering, two-row Sierra, Filter Lite, Atkinson dithering, or gradient-based error-diffusion dithering.

[0046] Using the respective coordinate determination methods, different sets of coordinates 13 of the respective impact positions 6 in the treatment area 7 can be determined. The resulting treatment roughnesses for the treatment volume 8, which depend on the coordinate determination method, can differ from one another. It may therefore be necessary to minimize the treatment roughness influenced by the choice of the coordinate determination method.

[0047] It can be provided that the control device 10 is configured to determine, prior to carrying out the treatment method according to a predetermined dithering roughness determination method, the coordinate determination method-dependent treatment roughnesses of the treatment volume 8 to be expected for the at least two coordinate determination methods for the predetermined treatment volume 8. In other words, the control device 10 is configured to determine which coordinate determination method-dependent treatment roughnesses would result for the respective coordinate determination methods when carrying out the treatment.The control device 10 can be configured to compare the treatment roughnesses of the respective coordinate determination methods, which are dependent on the coordinate determination method, with each other and to determine the coordinate determination method of the smallest expected treatment roughness, which is dependent on the coordinate determination method, as the predetermined coordinate determination method. This means that during the treatment method, the coordinates 13 of the respective impact positions 6 are set by the control device 10 according to the predetermined coordinate determination method in the at least one beam exit device 4.

[0048] One possibility for influencing the treatment roughness is to adapt the coordinates 13 of the impact positions 6 to varied coordinates 15 of the impact positions 6 using so-called jitter methods. Jitter methods can generate jitter shifts 16 from the coordinates 13 to the varied coordinates 15, which can be carried out randomly according to so-called random jitter methods or deterministically according to so-called deterministic jitter methods. The control device 10 can be configured to generate, before the eye treatment, respective varied coordinate sets comprising the varied coordinates 15 of the respective impact positions 6 from the coordinates 13 according to at least two jitter methods, wherein the varied coordinates 15 are shifted by respective jitter shifts 16 relative to the coordinates 13 in the treatment area 7.The control device 10 can be configured to determine the respective expected jitter-dependent treatment roughnesses of the treatment volume 8 for the respective coordinate sets according to the predetermined jitter roughness determination method and to replace the coordinates 13 with the varied coordinates 15 of the coordinate set of a smallest expected jitter-dependent treatment roughness. In other words, the control device 10 can be configured to determine the jitter-dependent treatment roughnesses that would result for the respective jitter methods for the respective jitter methods. The jitter method that would lead to the smallest expected jitter-dependent treatment roughness is used to replace the coordinates 13 with the varied coordinates 15.

[0049] It can be provided that the ablation of the predetermined treatment volume 8 can be carried out layer by layer, whereby the layers 17 of the treatment volume 8 arranged below one another can differ from one another in their predetermined laser pulse cross-sectional profile 5, the selected coordinate determination method, and / or the selected jitter method. This can, for example, reduce surface roughness in the base area 12 of the treatment volume 8. It is also possible to separately consider depth-dependent effects at different depths of the treatment volume 8.

[0050] A computer program 23 may include instructions that cause the treatment device 1, for example, controlled by the control device 10, to perform an eye treatment method. The computer program 23 may be stored on a computer-readable medium, for example, a hard disk, a USB stick, or a CD.

[0051] Fig. 2 shows a schematic representation of two patterns. The two patterns 20 show respective distributions of cutting depths 21 in µm in the treatment area 7, which can result from ablation of the treatment volume 8. The treatment area 7 can lie in an XY plane. The patterns 20 can result from the positions 13, which are determined using the respective dither methods. The positions 13 can be determined for the identical laser pulse cross-sectional profile 5 using two different coordinate determination methods. Depending on the selected coordinate determination method, the surface roughnesses of the side surfaces 11 and / or the base surface 12 of the treatment volume 8 can differ from one another.

[0052] Fig. 3 shows a schematic representation of a shift of coordinates by jitter shifts. The respective jitter method can specify the jitter shifts 16 by which the varied coordinates 15 of the impact points 6 are shifted relative to the coordinates 13 of the impact points 6. The jitter method can, for example, be a random jitter method, which can specify a shift of the coordinates 13 relative to the varied coordinates 15 by randomly based values. A deterministic jitter method can also be specified, which can, for example, specify periodic jitter shifts 16 across neighboring impact points 6.

[0053] Fig. Figure 4 shows possible laser pulse cross-section profiles. It shows the radial profile 22 of the radiant exposure H across the radial cross section R of the laser cross-section profiles. The laser pulse cross-section profiles 5 can differ from one another in their profiles 22, their maximum irradiances 14, and / or their half-widths 18. It can be provided that the laser pulse cross-section profiles 5 are guided through an aperture to limit them to a pinhole width 19.

[0054] Fig. 5 shows a schematic representation of a sequence of a method for controlling the treatment device.

[0055] In a first step S1, a treatment volume 8 to be ablated, which comprises a treatment area 7 of an eye 9, can be specified to the control device 10. In other words, the control device 10 can receive a treatment volume 8 to be treated by the treatment device 1.

[0056] It can be provided that, in a second step S2 of the method, parameters for carrying out the treatment method are determined by the control device 10. The determination can comprise several sub-steps, which can be carried out in parallel or sequentially.

[0057] In the second step S2, the control device 10 can determine a coordinate determination method and / or a jitter method and / or a laser pulse cross-sectional profile 5, which can lead to minimal treatment roughness of the treatment volume 8. The determination of the predetermined coordinate determination method, the determination of the predetermined laser pulse cross-sectional profile 5 and / or the determination of the predetermined jitter method can be carried out in parallel or sequentially.

[0058] In a sub-step A1 of step S2, at least two of the laser pulse cross-sectional profiles 5, which the laser pulses 3 emitted by the treatment device 1 may have, can be retrieved from a memory by the control device 10.

[0059] In a sub-step A2 of step S2, the control device 10 can determine, according to a predetermined profile determination method for the at least two laser pulse cross-sectional profiles 5 of the laser pulses 3, respective profile-dependent treatment roughnesses of the treatment volume 8 to be expected for the predetermined treatment volume 8.

[0060] In a sub-step A3 of step S2, the control device 10 can determine that of the at least two laser pulse cross-sectional profiles 5 as the predetermined laser pulse cross-sectional profile 5 which has a smallest expected profile-dependent treatment roughness.

[0061] In a sub-step B1 of step S2, the control device 10 can determine the coordinates 13 of the respective impact positions 6 in the treatment area 7 for the specified treatment volume 8 and the predetermined laser pulse cross-sectional profile 5 according to the respective coordinate determination methods. In other words, the coordinates 13 of the respective impact positions 6 are determined by the control device 10 according to at least two different coordinate determination methods for the treatment area 7.

[0062] In a sub-step B2 of step S2, according to a predetermined roughness determination method for the at least two coordinate determination methods, the respective coordinate determination method-dependent treatment roughnesses of the treatment volume 8 to be expected for the specified treatment volume 8 can be determined. The coordinate determination method-dependent treatment roughnesses can be determined, for example, by means of simulations or mathematical methods.

[0063] In a sub-step B3 of step S2, the coordinate determination method that results in the smallest coordinate determination method-dependent treatment roughness can be determined. This coordinate determination method can be used as the predetermined coordinate determination method for performing the eye treatment by the control device 10.

[0064] In a sub-step C1 of step S2, it can be provided that the coordinates 13 of the impact positions 6 are transformed by the control device 10 according to at least two jitter methods to varied coordinates 15, wherein the varied coordinates 15 can be shifted by jitter shifts 16 from the coordinates 13.

[0065] In a sub-step C2 of step S2, the control device 10 can determine the respective expected jitter-dependent treatment roughnesses of the treatment volume 8 according to a predetermined jitter roughness determination method for the respective jitter methods.

[0066] In a sub-step C3 of step S2, it can be provided that the coordinates 13 are replaced by the varied coordinates 13 of the jitter method of a smallest expected jitter-dependent treatment roughness.

[0067] By determining the coordinate determination method, the jitter method and the laser pulse cross-sectional profile 5 before the treatment, which each lead to a minimum treatment roughness of the treatment volume 8, a minimum treatment roughness of the treatment volume 8 can be achieved by the treatment.

[0068] The method steps can be repeated for different layers 17 of the treatment volume 8. The layers 17 can be sub-volumes of the treatment volume 8, which can be arranged one below the other or next to each other with respect to depth.

[0069] In a method step S3, the treatment method can be carried out, wherein the treatment device 1 can be controlled by the control device 10 so that the treatment device 1 outputs the laser pulses for treating the treatment volume 8.

[0070] The invention has the advantage that the values ​​which lead to minimal roughness are determined before the eye treatment is carried out. List of reference symbols: 1 treatment device 2 laser beam source 3 laser pulses 4 Radiation exit device 5 Laser pulse cross-section profile 6 impact positions 7 treatment area 8 treatment volumes 9 Eye 10 Control device 11 Side surface 12 floor space 13 coordinates 14 Maximum irradiation 15 Varied Coordinates 16 Jitter shift 17 layers 18 half-width 19 pinhole width 20 patterns 21 cutting depth 22 Course of a laser pulse cross-section profile 23 computer program 24 Computer-readable medium S1-S3 process steps A1-A3 sub-process steps B1-B3 sub-process steps C1-C3 sub-process steps

Claims

[1] Treatment device (1) for an eye treatment, comprising at least: - at least one laser beam source (2) arranged to emit laser pulses (3), - at least one beam exit device (4) which is designed to direct the respective laser pulses (3) with a predetermined laser pulse cross-sectional profile (5) to respective impact positions (6) in a treatment area (7) of a predetermined treatment volume (8) of an eye (9) to be treated, - a control device (10) which is designed to determine coordinates (13) of the respective impact positions (6) in the treatment area (7) according to at least two predetermined coordinate determination methods for the predetermined treatment volume (8) and the predetermined laser pulse cross-sectional profile (5), wherein the at least two predetermined coordinate determination methods describe respective patterns and / or algorithms which specify a determination of the coordinates (13) of the respective impact positions (6) for the predetermined treatment volume (8), - to determine, according to a predetermined roughness determination method for the at least two predetermined coordinate determination methods, respective treatment roughnesses of the treatment volume (8) to be expected for the predetermined treatment volume (8), which are dependent on the coordinate determination method, - to determine the predetermined coordinate determination method of a smallest expected, coordinate determination method-dependent treatment roughness as the coordinate determination method to be set, and - to set the coordinates (13) of the respective impact positions (6) according to the coordinate determination method to be set in the at least one beam exit device (4). [2] Treatment device (1) according to claim 1, characterized by , that - the control device (10) is designed to determine, prior to the eye treatment, profile-dependent treatment roughnesses of the treatment volume (8) to be expected for the predetermined treatment volume (8) for at least two potential laser pulse cross-sectional profiles (5) of the laser pulses (3), - to determine the potential laser pulse cross-sectional profile (5) of a smallest expected, profile-dependent treatment roughness as the predetermined laser pulse cross-sectional profile (5), and - to set the predetermined laser pulse cross-sectional profile (5) in the at least one beam exit device (4). [3] Treatment device (1) according to claim 1 or 2, characterized by , that - the control device (10) is designed to determine, prior to the eye treatment, respective sets of coordinates, comprising varied coordinates (15) of the respective impact positions (6), from the coordinates (13) according to at least two predetermined jitter methods, wherein the varied coordinates (15) of the sets of coordinates are shifted by respective jitter shifts (16) relative to the coordinates (13) in the treatment area (7), - to determine the respective expected, jitter-dependent treatment roughnesses of the treatment volume (8) for the respective coordinate sets according to a predetermined jitter roughness determination method, and - to replace the coordinates (13) by the varied coordinates (15) of the coordinate set of a smallest expected jitter-dependent treatment roughness. [4] Treatment device (1) according to one of the preceding claims, characterized by that the at least two predetermined coordinate determination methods comprise at least one predetermined dithering method. [5] Treatment device (1) according to claim 4, characterized byin that the at least two predetermined coordinate determination methods comprise at least one of the following predetermined dithering methods: Floyd-Steinberg, thresholding, random dithering, ordered dithering, Bayer matrix, minimized average error, Stucki dithering, Burkes dithering, Sierra dithering, two-row Sierra, Filter Lite, Atkinson dithering, or gradient-based error-diffusion dithering. [6] Treatment device (1) according to claim 2 or according to one of claims 3 to 5 with reference back to claim 2, characterized by that the at least two potential laser pulse cross-sectional profiles (5) comprise at least one Gaussian cross-sectional profile. [7] Treatment device (1) according to claim 2 or according to one of claims 3 to 6 with reference back to claim 2, characterized by that the at least two potential laser pulse cross-sectional profiles (5) comprise at least one pinhole cross-sectional profile. [8] Treatment device (1) according to claim 2 or according to one of claims 3 to 7 with reference back to claim 2, characterized by that the at least two potential laser pulse cross-sectional profiles (5) have different half-widths (18). [9] Treatment device (1) according to claim 2 or according to one of claims 3 to 8 with reference back to claim 2, characterized by that the at least two potential laser pulse cross-sectional profiles (5) have different maximum irradiations (14). [10] Treatment device (1) according to claim 3 or according to one of claims 4 to 9 with reference back to claim 3, characterized by that the at least two predetermined jitter methods comprise at least one random-based jitter method. [11] Treatment device (1) according to claim 3 or according to one of claims 4 to 10 with reference back to claim 3, characterized bythat the at least two predetermined jitter methods comprise at least one deterministic jitter method. [12] Method for controlling a treatment device (1) by a control device (10) which is designed to control the treatment device (1), comprising at least the steps: - Determining coordinates (13) of respective impact positions (6) in a treatment area (7) for a predetermined treatment volume (8) and a predetermined laser pulse cross-sectional profile (5) according to at least two predetermined coordinate determination methods, wherein the at least two predetermined coordinate determination methods describe respective patterns and / or algorithms which specify a determination of the coordinates (13) of the respective impact positions (6) for the predetermined treatment volume (8), - determining respective treatment roughnesses of the treatment volume (8) to be expected for the predetermined treatment volume (8), which are dependent on the coordinate determination method, according to a predetermined roughness determination method for the at least two predetermined coordinate determination methods, - Determining the predetermined coordinate determination method of a smallest expected, coordinate determination method-dependent treatment roughness as a coordinate determination method to be set, and - Setting the coordinates (13) of the respective impact positions (6) of the coordinate determination method to be set in the beam exit device (4). [13] Method for controlling the treatment device (1) according to claim 12, comprising the further steps: - determining the respective profile-dependent treatment roughnesses of the treatment volume (8) to be expected for the given treatment volume (8) for the at least two potential laser pulse cross-sectional profiles (5) of the laser pulses (3) according to the predetermined profile determination method, - determining the laser pulse cross-sectional profile (5) of the smallest expected, profile-dependent treatment roughness as the predetermined laser pulse cross-sectional profile (5), and - Setting the predetermined laser pulse cross-sectional profile (5) in the at least one beam exit device (4), and / or the further steps: - determining respective coordinate sets, comprising varied coordinates (15) from the coordinates (13) according to the at least two predetermined jitter methods, wherein the varied coordinates (15) of the coordinate sets are shifted by respective jitter shifts (16) in the treatment area (7) relative to the coordinates (13) in the treatment area (7), - determining the respective jitter-dependent treatment roughnesses of the treatment volume (8) to be expected for the given treatment volume (8) for the respective coordinate sets according to the predetermined jitter roughness determination method, and - Replacing the coordinates (13) by the varied coordinates (15) of the coordinate set of the smallest expected jitter-dependent treatment roughness. [14] Computer program (23) comprising instructions which cause a control device (10) to carry out the method steps according to claim 12 or 13. [15] A computer-readable medium (24) on which the computer program (23) according to claim 14 is stored.

Images