SYSTEM, CONTACT DEVICE AND METHOD FOR MAKING A CONTACT DEVICE

Description

[0001] The invention relates to a system, a contact device and a method for producing a contact device. State of the art

[0002] In an ophthalmic laser therapy system, a contact device in the form of a contact lens or a fluid patient interface is used to fix the relative geometric position of a patient's eye to a laser applicator (see, for example, WO 2016 / 100439 A1). In the contact lens or fluid patient interface, an optically active lens element is held in a fixed or predetermined position in the contact device. For this purpose, the lens element is often attached to the contact device using adhesive in the prior art.

[0003] The disadvantage of this is that the manufacturing process of attaching the lens element to the contact elements to create the contact device is time-consuming and labor-intensive, and technically complex. Furthermore, it requires special tools and specially trained personnel. Disclosure of the invention

[0004] The invention is based on the object of demonstrating a system or a contact device or a method for producing a contact device which is technically easy to produce or which is technically easy to carry out.

[0005] This object is achieved by a system according to claim 1, a contact device according to claim 4 and a method according to claim 13.

[0006] In particular, the object is achieved by a system comprising a contact element for fixing the relative geometric position of a patient's eye to a laser applicator of an ophthalmic laser therapy system, and a lens element for insertion into the contact element, wherein the contact element is designed to receive the lens element at a predetermined position, wherein the lens element has an eye surface for contacting the patient's eye or for airtightly defining a cavity between the lens element and the patient's eye, wherein the lens element has at least one projection element for engaging under one or more holding elements of the contact element for adhesive-free fastening of the lens element in the contact element by means of a snap connection, wherein the lens element has a lens contact surface formed on the underside of the projection element facing the eye surface,wherein the lens element and the contact element are designed such that the lens element can be fastened in the contact element by means of the snap connection such that the lens contact surface is pressed by means of the at least one projection element and the one or more holding elements against an elastic compensating element arranged on a fastening surface of the contact element in order to reduce the forces acting on the lens element by the one or more holding elements.

[0007] One advantage of this is that the system is technically particularly simple to manufacture, and the lens element can be inserted or fastened into the contact element to form a contact device. In particular, the lens element can be inserted and fastened manually into the contact element using simple, commonly available tools to produce the contact device. Automated insertion or fastening is also possible. In particular, no special tools are required to fasten the lens element to the contact element to produce the contact device. Furthermore, the person who fastens the lens element in the contact element does not need to have any special technical training or education. Thus, a large number of contact devices comprising the contact element and the lens element inserted or fastened in the contact element can be manufactured within a very short time.Furthermore, the space required to manufacture the contact device comprising the contact element and the lens element inserted into or secured in the contact element is particularly small. Furthermore, manufacturing costs are low. Furthermore, since no adhesive is required to secure the lens element in the contact element, unintentional bonding of other elements to one another or adhesion of adhesive in undesired locations is reliably prevented. The compensating element reliably prevents any change in the optical properties of the lens element.

[0008] In particular, the object is also achieved by a contact device for fixing the relative geometric position of a patient's eye to a laser applicator of an ophthalmic laser therapy system, wherein the contact device comprises a contact element and a lens element, wherein the lens element is firmly connected to the contact element without adhesive by means of a snap connection, wherein the lens element has an eye surface for contacting the patient's eye or for airtightly defining a cavity between the lens element and the patient's eye, wherein the lens element has at least one projection element for engaging under one or more holding elements of the contact element for adhesive-free fastening of the lens element in the contact element by means of a snap connection, wherein the lens element has a lens contact surface formed on an underside of the projection element facing the eye surface,wherein the lens element is fastened in the contact element by means of the snap connection in such a way that the lens contact surface is pressed by means of the at least one projection element and the one or more holding elements against an elastic compensating element arranged on a fastening surface of the contact element in order to reduce the forces acting on the lens element by the one or more holding elements.

[0009] The advantage of this is that the contact device is technically particularly simple to manufacture. In particular, the lens element can be technically particularly simple to fasten in the contact element. No special or adapted tools are required for the manufacture of the contact device. The manufacture of the contact device can be automated or carried out by machine. The person who fastens the lens element in the contact element does not need to have any special technical training or education to manufacture the contact device. This means that a large number of contact devices comprising the contact element and the lens element inserted into the contact element or fastened in the contact element can be manufactured within a very short time. In addition, the space required for manufacturing the contact device comprising the contact element and the lens element inserted into the contact element orThe lens element mounted in the contact element is particularly small. Furthermore, manufacturing costs are low. Furthermore, since no adhesive is required or used to secure the lens element in the contact element, unintentional bonding of other elements to one another or adhesion of adhesive in undesired locations is reliably prevented. The compensating element reliably prevents any change in the optical properties of the lens element.

[0010] In particular, the object is also achieved by a method for producing a contact device for fixing the relative geometric position of a patient's eye to a laser applicator of an ophthalmological laser therapy system, wherein the contact device has a contact element and a lens element, the method comprising the following steps: Providing a contact element with one or more holding elements; providing a lens element, wherein the lens element has an eye surface for contacting the patient's eye or for airtightly defining a cavity between the lens element and the patient's eye, wherein the lens element has at least one projection element for engaging beneath the one or more holding elements of the contact element for adhesive-free fastening of the lens element in the contact element by means of a snap connection, wherein the lens element has a lens contact surface formed on the underside of the at least one projection element facing the eye surface;and adhesive-free fastening of the lens element in the contact element by means of a snap connection, in that the at least one projection element is snapped under the holding element(s) in such a way that the lens contact surface is pressed by means of the at least one projection element and the one holding element or the plurality of holding elements against an elastic compensating element arranged on a fastening surface of the contact element in order to reduce the forces acting on the lens element by the one holding element or the plurality of holding elements.

[0011] One advantage of this process is that it is technically simple and quick to perform. It also requires little space. Furthermore, no specially adapted tools are required. The personnel performing the process do not require special training. Consequently, the process is cost-effective. The compensating element reliably prevents any change in the optical properties of the lens element. Furthermore, since no adhesive is used to firmly bond the lens element to the contact element, unintentional bonding of other elements to one another or adhesion of adhesive to unwanted locations is reliably prevented.

[0012] According to one embodiment of the system, the lens element and the contact element are designed such that the lens element can be fastened in the contact element such that the compensating element is arranged completely circumferentially around the optical axis of the lens element. The advantage of this is that the forces that occur are distributed particularly evenly across the lens element and the fastening surface. This even more reliably prevents negative effects on the optical properties of the lens element.

[0013] According to one embodiment of the system, the compensating element is designed to hermetically seal the area between the lens contact surface and the fastening surface. One advantage of this is that a contact device that seals at this point as a liquid patient interface, or a contact lens that is suctioned over the entire contact surface, can be designed or manufactured technically easily. The compensating element can thus simultaneously assume the function of a sealing element. It is possible for the lens element to be fastened in the contact element in such a way that the compensating element is not arranged completely circumferentially around the optical axis of the lens element and yet, when placed on the patient's eye or when suctioned onto the patient's eye, the area between the lens contact surface and the fastening surface is sealed essentially tightly or essentially hermetically.For example, by applying suction to the patient's eye, a portion of the lens contact surface can be connected to a portion of the attachment surface where no compensating element is present, essentially sealingly or essentially airtight. The suction system can compensate for the gaps between the spaced-apart compensating elements.

[0014] According to one embodiment of the contact device, the lens element is mounted in the contact element in such a way that the compensating element is arranged completely circumferentially around the optical axis of the lens element. One advantage of this is that, with the contact device, the forces occurring are distributed particularly evenly across the lens element and the mounting surface, thus avoiding stresses. This further prevents negative effects on the optical properties of the lens element.

[0015] According to one embodiment of the system or contact device, the lens contact surface runs perpendicular to the optical axis of the lens element. One advantage of this is that the forces acting on the lens element can be distributed particularly efficiently and over a large area.

[0016] According to one embodiment of the system or contact device, the fastening surface of the contact element extends perpendicular to the optical axis of the lens element when the lens element is fastened in the contact element. This allows forces to be transmitted to the contact element efficiently and over a large area by the snap connection. This reliably prevents the optical properties of the lens element from changing. Furthermore, if the lens contact surface is arranged parallel to the fastening surface, the compensating element can be in contact with the lens contact surface and the fastening surface over a large area.

[0017] According to one embodiment of the system or the contact device, the at least one projection element of the lens element comprises or is a bead that essentially completely surrounds the optical axis of the lens element, or the at least one projection element has a plurality of projection elements arranged at a distance from one another around the optical axis of the lens. The advantage of a circumferential bead is that the lens element, or the system, or the contact device, is technically even easier to manufacture. Furthermore, with a circumferential bead, the holding element or elements can secure the lens element over a particularly large area and hold it in a predetermined position. Furthermore, with a circumferential bead, the lens element can be rotated about the optical axis of the lens element relative to the contact element.The advantage of having several projection elements spaced apart from one another is that the lens element can be attached or inserted into the contact element particularly easily.

[0018] According to one embodiment of the system or contact device, the compensating element is substantially circular in cross-section perpendicular to the optical axis of the lens element when the lens element is secured in the contact element. One advantage of this is that the compensating element is particularly easy to arrange technically. This reduces manufacturing costs and reduces the time required for production. Furthermore, the forces can be transferred particularly evenly from the lens element to the compensating element. This prevents potential negative effects on the optical properties of the lens element even more reliably.

[0019] According to one embodiment of the system or contact device, the contact element comprises a plurality of retaining elements, which are arranged, in particular equidistant from one another, spaced apart from one another around the optical axis of the lens when the lens element is fastened in the contact element. This is advantageous in that the lens element can be inserted into the contact element in a technically simple manner. Furthermore, no significant forces act on the lens element when inserting the lens element into the contact element or when establishing the snap connection, so that a change in the optical properties of the lens element is reliably prevented even when inserted into the contact element.

[0020] According to one embodiment of the system or contact device, the one or more retaining elements of the contact element are designed to be flexible such that the one or more retaining elements are designed to be mechanically movable for engaging the at least one projection of the lens element under the retaining element or elements to form the snap connection. This allows the lens element to be inserted into the contact element in a technically simple manner, in particular manually. Furthermore, only small forces act on the lens element during insertion of the lens element into the contact element. This reliably prevents a (permanent) change in the optical properties of the lens element.

[0021] According to one embodiment of the system or contact device, the compensating element has a marking and / or color associated with the respective contact device type. This is advantageous because humans can quickly and reliably visually distinguish between different contact device types. This reliably prevents misuse or incorrect selection of the contact device. Different contact device types can, for example, each comprise different lens elements and each comprise identical contact elements.

[0022] According to one embodiment of the method, the lens contact surface runs perpendicular to the optical axis of the lens element. This is advantageous in that the forces acting on the lens element are distributed particularly efficiently and over a large area.

[0023] According to one embodiment of the method, the contact element comprising the flexible compensating element is manufactured using a multi-component injection molding process, in particular a two-component injection molding process. This has the advantage that the contact device can be manufactured technically simply, quickly, and cost-effectively. Furthermore, no additional work step is required for arranging the compensating element.

[0024] According to one embodiment of the method, the one or more holding elements of the contact element are reversibly moved mechanically, in particular away from the optical axis of the lens element, to insert a portion of the at least one projection of the lens element between the holding element or the holding elements of the contact element and the fastening surface of the contact element to form the snap connection. One advantage of this is that the lens element can be inserted into the contact element in a technically simple manner, in particular manually. Furthermore, only small forces act on the lens element during insertion. This reliably prevents a (permanent) change in the optical properties of the lens element.

[0025] According to one embodiment of the method, the at least one projection element of the lens element comprises a bead that extends substantially completely around the optical axis of the lens element. One advantage of this is that the contact device is technically even easier to manufacture. The lens element is also secured over a particularly large area by the retaining element or elements and held in a predetermined position. Furthermore, rotation of the lens element about the optical axis of the lens element relative to the contact element does not change the fastening of the lens element in the contact element.

[0026] It is conceivable that the contact element has one or more recesses into which the compensating element is at least partially pressed when the lens element is inserted into the contact element, and into which the compensating element can partially deflect, so to speak. This further reduces the forces acting on the lens element.

[0027] Preferred embodiments are set out in the dependent claims. The invention is explained in more detail below with reference to drawings of exemplary embodiments. Fig. 1 is a schematic side view of an embodiment of the contact device according to the invention; Fig. 2 is a detailed view of the area II of Fig. 1 ; and Fig. 3 a plan view of the contact element of the contact device from Fig. 1 or Fig. 2 .

[0028] In the following description, the same reference numbers are used for identical and equivalent parts.

[0029] Fig. 1 shows a schematic side view of an embodiment of the contact device 5 according to the invention. Fig. 2 shows a detailed view of area II from Fig. 1 . Fig. 3 shows a plan view of the contact element 40 of the contact device 5 from Fig. 1 or Fig. 2 from above, i.e. in the direction of the light beam during treatment of the patient's eye.

[0030] The contact device 5 is designed to fix the relative geometric position of a patient's eye to a laser applicator of an ophthalmic laser therapy system. The contact device 5 thus fixes the position of the eye with respect to the laser radiation during laser treatment. The contact device 5 is or will be rigidly / fixedly attached to the laser therapy system.

[0031] The contact device 5 comprises a lens element 10 which is fastened in the contact element 40 of the contact device 5 at or in a predetermined position by means of a snap connection without adhesive.

[0032] The contact device 5 can be a contact lens holder (colloquially also simply called a "contact lens") in which the lens element 10 touches the eye or cornea. It is possible for the contact device 5 to be a liquid patient interface in which a cavity between the lens element 10 and the patient's eye is filled with a physiological saline solution (buffered salt solution, abbreviated to BSS). The saline solution can be used to adjust the refractive index between the lens element 10 and the patient's eye. A liquid patient interface can be used, particularly when focusing the laser radiation on deeper structures in the patient's eye.

[0033] The lens element 10 is fixedly mounted or arranged at a predetermined position in the contact element 40 of the contact device 5. This means that the relative position between the lens element 10 and the contact element 40 is essentially unchangeable.

[0034] The lens element 10 is firmly inserted into the contact element 40 by means of a snap connection or click connection, i.e., it is firmly connected to the contact element 40 or fastened in the contact element 40. The snap connection forms a positive fit.

[0035] The optical axis 20 of the lens element 10 runs centrally through the lens element 10, ie in Fig. 1 or Fig. 2 from top to bottom. In Fig. 3 the optical axis 20 of the lens element 10 runs perpendicular to the plane of the drawing when the lens element 10 is or will be fastened at the predetermined position in the contact element 40.

[0036] To establish the snap connection between the lens element 10 and the contact element 40, the lens element 10 has a projection element 25, e.g., in the form of a circumferential bead, or a plurality of projection elements 25. The plurality of projection elements 25 can be circumferentially spaced from one another around the optical axis 20. For example, the plurality of projection elements 25 can be circumferentially spaced equidistant from one another around the optical axis 20. For example, six projection elements 25, each extending over 30° of the full circle or circumference, can each be spaced 30° apart from one another in the circumferential direction. Other configurations of projection elements 25 are conceivable.

[0037] The contact element 40 has a frustoconical outer shape. The contact element 40 has a retaining element 42 or several retaining elements 42-47 on its inner side. The retaining element 42 or the retaining elements 42-47 are designed as projections extending inward or toward the optical axis 20 of the lens element 10.

[0038] The holding element 42-47 can be configured to completely encircle the optical axis 20 of the lens element 10, i.e., extend over a full circle around the optical axis 20 of the lens element 10. Alternatively, it is possible for several holding elements 42-47 to be spaced apart from one another in the circumferential direction, in particular equidistantly. Like the projection elements 25, the holding elements 42-47 can each extend over a circular arc segment, e.g., over 35° of the circumference. Alternatively, there can also be three holding elements 42-47, each arranged offset from one another by 120° in the circumferential direction.

[0039] The contact element 40 has a fastening surface 49. The lens element 10 has a lens contact surface 15 on the side facing the eye. The lens contact surface 15 can run perpendicular to the optical axis 20 of the lens element 10. The fastening surface 49 can be formed perpendicular to the optical axis 20 of the lens element 10. When the lens element 10 is inserted into the contact element 40 and secured by means of a snap connection, the lens contact surface 15 and the fastening surface 49 run parallel to one another.

[0040] The lens element 10 is secured in the holding element 42-47 without adhesive. In particular, there is no adhesive between the lens contact surface 15 and the fastening surface 49.

[0041] The lens element 10 is fastened in the contact element 40 by inserting the projection element 25 or the projection elements of the lens element 10 under the holding element 42-47 or the holding elements 42-47 of the contact element 40 and snapping them into place. For this purpose, the projection elements 25 or the holding elements 42-47 can be reversibly mechanically movable. In particular, the projection elements 25 and / or the holding elements 42-47 can be reversibly movable away from or toward the optical axis 20 of the lens element 10. By inserting the projection element 25 or the projection elements 25 under the holding element 42-47 or the holding elements 42-47, the snap connection or click connection between the lens element 10 and the contact element 40 is formed. Thus, a positive connection is formed between the holding element 42-47 and the projection element 25, which essentially prevents movement of the lens element 10 relative to the contact element 40.

[0042] The projection element 25 is held between the holding element 42-47(s) and the fastening surface 49. The projection element 25 and the holding element 42-47 press the lens contact surface 15 toward the fastening surface 49.

[0043] An elastic compensating element 50 is arranged on the mounting surface 49. The compensating element 50 is elastic, meaning that the compensating element 50 strives to return to its original shape. The compensating element 50 can comprise a plastic material or be made of plastic. For example, the compensating element 50 is made of a rubber-plastic material.

[0044] It is possible, but not mandatory, for a recess or depression to be formed in the mounting surface 49 to accommodate a portion of the compensating element 50. In this way, the compensating element 50 can be positioned particularly precisely.

[0045] The compensating element 50 can be annular in a cross-sectional plane perpendicular to the optical axis 20 of the lens element 10. The compensating element 50 can be toroidal, similar to an O-ring. Other shapes are possible. For example, it can have a donut shape.

[0046] The compensating element 50 can be designed to completely encircle the optical axis 20 of the lens element 10.

[0047] The compensating element 50 can be designed to be airtight. This allows the area between the lens contact surface 15 and the fastening surface 49 to be sealed airtight. This is particularly important for a liquid-patient interface, since the cavity between the lens element 10 and the patient's eye, delimited by the eye surface 30 of the lens element 10, should be sealed. This is equally important for a contact element designed as a contact glass and whose entire contact surface is suctioned onto the eye. However, it is also possible, particularly when designed as a liquid-patient interface, for an additional suction ring to be present, for example, on the outer circumference or near the outer circumference of the contact element 40, wherein the suction ring is designed to suction onto the patient's eye and thus to fix the contact element 40 relative to the patient's eye.With an additional suction ring, for example, there is no need for an airtight seal of the cavity between the lens element 10 and the patient's eye.

[0048] It is also conceivable for the compensating element 50 to have a plurality of spaced-apart segments that are spaced from one another in the circumferential direction, in particular equidistantly, around the circumference of the fastening surface 49. For example, a segment of the compensating element 50 is located at 6 points on the fastening surface 49. The various segments of the compensating element 50 typically have the same elasticity. With a plurality of spaced-apart segments of the compensating element 50 or with a plurality of spaced-apart compensating elements, it is conceivable that the pressure of the lens contact surface 15 against the fastening surface 49 forms a sealing closure or an airtight closure of the area between the lens contact surface 15 and the fastening surface 49.

[0049] The contact element 40 is designed to be at least partially complementary to the lens element 10, in particular such that lateral movement, i.e., movement perpendicular to the optical axis 20 of the lens element 10, is essentially impossible when the lens element 10 is firmly connected to the contact element 40 by means of the snap connection or is fastened in the contact element 40. This provides a snug fit in the lateral or sideways direction. Thus, forces do not constantly act on the lens element 10 in the lateral or sideways direction.

[0050] However, it is conceivable that a further compensating element 50 is also arranged in the lateral direction between the lens element 10 and the contact element 40. The further compensating element 50 can extend around the optical axis 20 of the lens element 10 in a full circle or consist only of individual circular segments or arc segments.

[0051] The compensating element 50 is clamped, so to speak, between the lens contact surface 15 and the fastening surface 49. It is conceivable that the compensating element 50 covers the largest part, in particular more than 90%, of the lens contact surface 15 and / or the fastening surface 49.

[0052] The compensating element 50 prevents excessive forces from acting on the lens element 10 or tensions from developing in the lens element 10 that could alter the optical properties of the lens element 10. The compensating element 50 prevents the lens contact surface 15 from pressing directly against the mounting surface 49.

[0053] The compensating element 50 does not comprise any adhesive and does not perform any adhesive function.

[0054] The compensating element 50 deforms when the lens element 10 or the lens contact surface 15 is pressed toward the fastening surface 49. Due to its elasticity, the compensating element 50 presses against the lens contact surface 15. This prevents movement of the lens element 10 parallel to the optical axis 20. The compensating element 50 thus represents a type of buffer between the lens contact surface 15 and the fastening surface 49, which can absorb forces through deformation, so that typically no direct or immediate contact is established between the essentially non-deformable lens contact surface 15 and the essentially non-deformable fastening surface 49.

[0055] The contact element 40 with the compensating element 50 can be manufactured by means of an injection molding process. In particular, the contact element 40 can be manufactured by means of a two-component injection molding process or a two-component injection molding process. The contact element 40 without the compensating element 50 can consist of or be manufactured from a first component, and the compensating element 50 can consist of or be manufactured from a second component, wherein the second component differs from the first component. The second component can comprise or be an elastic or flexible plastic or plastic mixture.

[0056] A therapy system surface 37 opposite the eye surface 30 is formed parallel to the eye surface 30. The therapy system surface 37 touches or contacts the holding element 42-47 of the contact element 40. There is a positive connection between the therapy system surface 37 and the holding element 42-47. The therapy system surface 37 can be Fig. 1 or Fig. 2 do not move upwards, since the therapy system surface 37 hits the holding element 42-47 of the contact element 40.

[0057] The therapy system surface 37 can be facing away from the eye surface 30. This means that the eye surface 30 is in Fig. 1 or Fig. 2 faces downward, while the therapy system surface 37 faces upward or is formed on the upper side of the projection of the lens element 10. The lens contact surface 15 is formed on the underside of the projection of the lens element 10.

[0058] The lens element 10 is inserted into the contact element 40 to form the contact device 5 by reversibly mechanically moving one or more holding elements 42-47. For example, one or more holding elements 42-47 can be partially bent laterally and / or parallel to the optical axis 20 of the lens element 10 in order to move the projection element 25 or the projection elements under the holding element 42-47 or the holding elements 42-47. Subsequently, the holding element 42-47 or the holding elements 42-47 move or snap back to their original position(s). A positive snap connection is now formed between the lens element 10 and the contact element 40. The projection element 25 or the projection elements of the lens element 10 are now located between the holding element 42-47 or the holding elements 42-47 and the fastening surface 49.The compensating element 50 is arranged between the projection element 25 and the fastening surface 49.

[0059] It is also conceivable that a projection element 25 or several projection elements of the lens element 10 are moved mechanically reversibly in order to insert the lens element 10 into the contact element 40 and to fasten it in the contact element 40 by means of a snap connection or click connection.

[0060] The snap connection typically cannot be removed from the contact element 40 without causing damage.

[0061] In Fig. 3 the lens element 10 is not yet inserted into the contact element 40.

[0062] It is possible that the entire contact device 5 does not have any adhesive or adhesive connection.

[0063] The contact device 5 may have a suction channel 60 for sucking the eye. List of reference symbols

[0064] 5Contact device 10Lens element 15Lens contact surface 20Optical axis of the lens 25Protrusion element 30Eye surface 37Therapy system surface 40Contact element 42-47Holding element 49Fastening surface 50Compensation element 60Suction channel

Claims

1. System comprising a contact element (40) for fixing the relative geometric position of a patient's eye to a laser applicator of an ophthalmic laser therapy system, and a lens element (10) for insertion into the contact element (40), wherein the contact element (40) is configured for receiving the lens element (10) at a predetermined position, wherein the lens element (10) has an eye surface (30) for contacting the patient's eye or for airtightly delimiting a cavity between the lens element (10) and the patient's eye, wherein the lens element (10) has at least one projection element (25) for engaging under one or more retaining elements (42-47) of the contact element (40) for adhesive-free fastening of the lens element (10) in the contact element (40) by means of a snap connection, wherein the lens element (10) has a lens contact surface (15) formed on an underside of the projection element (25) facing the eye surface (30), wherein the lens element (10) and the contact element (40) are configured in such a way that the lens element (10) can be fastened in the contact element (40) by means of the snap connection such that the lens contact surface (15) is pressed by means of the at least one projection element (25) and the one retaining element (42-47) or the plurality of retaining elements (42-47) against an elastic compensating element (50) arranged on an attachment surface (49) of the contact element (40) for reducing the forces acting on the lens element (10) by the one retaining element (42-47) or the plurality of retaining elements (42-47).

2. System according to claim 1, wherein the lens element (10) and the contact element (40) are configured such that the lens element (10) can be fastened in the contact element (40) such that the compensating element (50) is arranged completely circumferentially around the optical axis (20) of the lens element (10).

3. System according to claim 1 or 2, wherein the compensating element (50) is configured for airtight sealing of the area between the lens contact surface (15) and the attachment surface (49).

4. Contact device (5), wherein the contact device (5) comprises a system according to any one of claims 1-3, wherein the contact device (5) is configured for fixing the relative geometric position of the patient's eye to the laser applicator of the ophthalmic laser therapy system, wherein the lens element (10) is firmly connected to the contact element (40) without adhesive by means of the snap connection, wherein the lens element (10) is fastened in the contact element (40) by means of the snap connection in such a way that the lens contact surface (15) is pressed by means of the at least one projection element (25) and the one retaining element (42-47) or the plurality of retaining elements (42-47) against the elastic compensating element (50) arranged on the attachment surface (49) of the contact element (40) for reducing the forces acting on the lens element (10) by the one retaining element (42-47) or the plurality of retaining elements (42-47).

5. Contact device (5) according to claim 4, wherein the lens element (10) is fastened in the contact element (40) in such a way that the compensating element (50) is arranged completely circumferentially around the optical axis (20) of the lens element (10).

6. System according to any one of claims 1-3 or contact device (5) according to claim 4 or claim 5, wherein the lens contact surface (15) runs perpendicularly to the optical axis (20) of the lens element (10).

7. System according to any one of claims 1-3 or contact device (5) according to any one of claims 4-6, wherein the attachment surface (49) of the contact element (40) runs perpendicularly to the optical axis (20) of the lens element (10), when the lens element (10) is fastened in the contact element (40).

8. System according to any one of claims 1-3 or contact device (5) according to any one of claims 4-7, wherein the at least one projection element (25) of the lens element (10) comprises or is a bulge extending substantially completely around the optical axis (20) of the lens element (10) or the at least one projection element (25) comprises a plurality of projection elements (25) arranged at a distance from one another around the optical axis (20) of the lens.

9. System according to any one of claims 1-3 or contact device (5) according to any one of claims 4-8, wherein the compensating element (50) is substantially circular in a cross-section perpendicular to the optical axis (20) of the lens element (10), when the lens element (10) is fastened in the contact element (40).

10. System according to any one of claims 1-3 or contact device (5) according to any one of claims 4-9, wherein the contact element (40) comprises a plurality of retaining elements (42-47) which are arranged at a distance from one another, in particular equidistant from one another, around the optical axis (20) of the lens, when the lens element (10) is fastened in the contact element (40).

11. System according to any one of claims 1-3 or contact device (5) according to any one of claims 4-10, wherein the one or more retaining elements (42-47) of the contact element (40) is / are flexible such that the one or more retaining elements (42-47) is / are mechanically movable to engage the at least one projection of the lens element (10) under the retaining element (42-47) or the retaining elements (42-47) to form the snap connection.

12. System according to any one of claims 1-3 or contact device (5) according to any one of claims 4-11, wherein the compensating element (50) has a marking and / or color assigned to the respective layout of the contact device (5).

13. A method of manufacturing a contact device (5) for fixing the relative geometric position of a patient's eye to a laser applicator of an ophthalmic laser therapy system, wherein the contact device (5) comprises a contact element (40) and a lens element (10), wherein the method comprises the following steps: providing a contact element (40) with one or more retaining elements (42-47); providing a lens element (10), wherein the lens element (10) has an eye surface (30) for contacting the patient's eye or for airtightly delimiting a cavity between the lens element (10) and the patient's eye, wherein the lens element (10) has at least one projection element (25) for engaging under the one or more retaining elements (42-47) of the contact element (40) for adhesive-free fastening of the lens element (10) in the contact element (40) by means of a snap connection, wherein the lens element (10) has a lens contact surface (15) formed on an underside of the at least one projection element (25) facing the eye surface (30); and adhesive-free fastening of the lens element (10) in the contact element (40) by means of a snap connection by snapping in the at least one projection element (25) under the retaining element or elements (42-47) in such a way that the lens contact surface (15) is pressed by means of the at least one projection element (25) and the one retaining element (42-47) or the plurality of retaining elements (42-47) against an elastic compensating element (50) arranged on an attachment surface (49) of the contact element (40) for reducing the forces acting on the lens element (10) by the one retaining element (42-47) or the plurality of retaining elements (42-47).

14. Method according to claim 13, wherein the contact element (40) comprising the flexible compensating element (50) is manufactured by means of a multi-component injection molding process, in particular a two-component injection molding process.

15. Method according to claim 13 or 14, wherein the one or more retaining elements (42-47) of the contact element (40) are reversibly moved mechanically, in particular away from the optical axis (20) of the lens element (10), for inserting a part of the at least one projection of the lens element (10) between the retaining element (42-47) or the retaining elements (42-47) of the contact element (40) and the attachment surface (49) of the contact element (40) for forming the snap connection.