TEST DEVICE, TEST DEVICE SYSTEM AND METHOD FOR DETERMINING IF A LIQUID CONTAINS A SUBSTANCE

Description

[0001] The present invention relates to a test device and a method for determining whether a liquid contains a substance. Test devices for determining whether a liquid contains a substance are known from the prior art. The test devices known from the prior art have a sample area onto which a sample of a liquid, such as blood, can be applied. The liquid sample can contain a substance, such as immunoglobulin G or immunoglobulin M, in at least a minimum quantity. The test devices known from the prior art also have a result area configured to assume a first appearance if the sample contains the substance in at least the minimum quantity, and a second appearance if the sample does not contain the substance in at least the minimum quantity.Based on the first and second appearances, it can be concluded whether the ingredient is present in at least the minimum quantity or whether it is not present in at least the minimum quantity. Therefore, using test devices known from the prior art, it can be determined whether a liquid contains an ingredient.

[0002] In general, it is desirable that these test devices are suitable for distinguishing a specific test device from other specific test devices, while simultaneously preventing or at least significantly hindering the duplication of the specific test device, and ensuring that a test result is determined as having been obtained with a non-copied test device manufactured by a specific manufacturer.

[0003] The article GÖKÇE ONUR et al.: "High-Content Optical Codes for Protecting Rapid Diagnostic Tests from Counterfeiting", ANALYTICAL CHEMISTRY, Vol. 90, No. 12, June 19, 2018, pages 7383-7390, XP055853599, DOI: 10.1021 / acs.analchem.8b00826 discloses the marking of test strips with two-dimensional microcodes to make them more difficult to counterfeit.

[0004] It is therefore an object of the present invention to increase the reliability of test results. According to a first aspect of the invention, this object is achieved by a test device having the features of claim 1.

[0005] The testing device is designed to determine whether a liquid contains a specific ingredient. Therefore, the device can be used to determine if the liquid contains the ingredient. For example, the liquid could be blood, in which case the testing device is designed to examine blood for the presence of a particular ingredient. Alternatively, the liquid could be urine, in which case the testing device is designed to examine urine for the presence of a specific ingredient. Furthermore, the liquid could also be saliva, in which case the testing device is designed to examine saliva for the presence of a specific ingredient.Furthermore, the fluid can also be another bodily fluid, such as sweat, so the test device is designed to examine the bodily fluid, such as sweat, for the presence of a specific ingredient. The ingredient can be, for example, immunoglobulin G, so the test device is designed to examine the fluid for the presence of immunoglobulin G. Alternatively, the ingredient can also be, for example, immunoglobulin H, so the test device is designed to examine the fluid for the presence of immunoglobulin H. Furthermore, the ingredient can also be, for example, immunoglobulin M, so the test device is designed to examine the fluid for the presence of immunoglobulin M. In particular, the ingredient can be an antibody, such as immunoglobulin G, immunoglobulin H, or immunoglobulin M.The ingredient can also be an antigen. Furthermore, the test device can be adapted to determine whether the liquid contains a first ingredient and a second ingredient. In this case, the first ingredient can be immunoglobulin G and the second ingredient immunoglobulin H, so the test device is configured to examine the liquid for the presence of immunoglobulin G and immunoglobulin H. The test device can also be adapted to determine whether the liquid contains a variety of specific ingredients. The characteristics, technical effects, and / or advantages described in connection with the ingredient and the liquid also apply, at least analogously, to the first ingredient, the second ingredient, and the variety of specific ingredients, so a corresponding repetition is omitted here.For example, different minimum quantities and first and second manifestations may be specified for each of these ingredients.

[0006] The test device has a sample area onto which a sample of the liquid can be applied. Preferably, the liquid sample is a small quantity of the liquid. In particular, the liquid can also be referred to as the liquid to be tested. Furthermore, the test device has a result area configured to exhibit a first appearance when the sample contains the ingredient in at least a minimum quantity. If the result area exhibits the first appearance, it can be concluded that the sample contains the ingredient in at least the minimum quantity.

[0007] Furthermore, the result field is designed to assume a second appearance if the sample does not contain the ingredient in at least the minimum quantity. If the result field assumes the second appearance, it can be concluded that the sample does not contain the ingredient in at least the minimum quantity. Preferably, the first and second appearances differ from each other. This is achieved, for example, by the first appearance of the result field having a horizontal stripe in a control field of the result field, while the second appearance of the result field does not have the horizontal stripe in the control field of the result field.Alternatively, this can be achieved, for example, by the first appearance of the result field not having the horizontal stripe in the control field of the result field, and the second appearance of the result field having the horizontal stripe in the control field of the result field. It should be noted here that the present invention is not limited to the first appearance and the second appearance differing from each other by the appearance or absence of a horizontal stripe. Rather, the first appearance and the second appearance can also differ by other features, such as the appearance of a horizontal stripe in different positions or the appearance or absence of a filled area or unfilled borders, such as circles.

[0008] Furthermore, the test device features a safety field. The safety field can be configured in various ways, as explained in more detail below. Because the test device includes both the result field and the safety field, it is possible to correlate the two, for example, after they have been optically captured together by a single detection unit, such as by scanning or photographing.

[0009] The security field includes an information field with a structure. Specifically, the structure is a two-dimensional representation arranged such that when the security field is optically detected, the two-dimensional representation is also optically detected. The two-dimensional representation of the structure exhibits a Fourier pattern or is formed from one. It is specifically stipulated that the structure itself is not a QR code, DataMatrix, Cool Data Matrix, Aztec, UPCode, Trillcode, Quickmark, Shotcode, mCode, or Beetagg. Rather, in certain embodiments, the structure can be a section of a QR code, DataMatrix, Cool Data Matrix, or other format.

[0010] Aztecs, UPCodes, Trillcodes, Quickmarks, Shotcodes, mCodes, or Beetaggs are formed. This structure can also be referred to as a security structure. A first unique identification code is encoded within this structure. By capturing the structure and decoding the captured structure, the first unique identification code can be determined. The first unique identification code is unique and thus differs significantly from other unique identification codes. The unique identification code can also be referred to as a unique identifier (UID) or unique ID. The first unique identification code differs from other first unique identification codes primarily due to its uniqueness. Specifically, it is stipulated that no two structures exist, each encoding a first unique identification code, where the two first unique identification codes are identical.Because the first unique identification code is unique, the identity of the test device can be deduced from it. In particular, because the first unique identification code is unique, it allows the test device to be distinguished from other test devices that may appear identical or similar. The first unique identification code is encoded using a structure and is therefore in coded form, with the structure representing this coded form. Because the first unique identification code is encoded, a user of the test device cannot necessarily deduce it without technical aids, such as a data acquisition and / or evaluation unit.In particular, it is advantageous if the structure is designed in such a way that a user of the test device cannot deduce the first unique identification code without technical aids. If the user of the test device cannot deduce the first unique identification code, especially not necessarily without technical aids, it is ensured that duplication of the test device with the first unique identification code is significantly hindered or even prevented.

[0011] The first unique identification code can only be decoded from the structure if it is constructed with a minimum resolution. Constructing the structure can also be referred to as generating the structure. In particular, the structure is so fine that a minimum resolution is necessary, especially for its construction, so that the structure can be represented in such a way that the first unique identification code can be decoded from it. The structure is designed as a Fourier pattern.

[0012] The minimum resolution at which the structure is produced is preferably 300 dpi. In particular, it has proven advantageous if the minimum resolution is greater than 300 dpi. It is even more advantageous if the minimum resolution at which the structure is produced is 600 dpi. It is even more advantageous if the minimum resolution at which the structure is produced is greater than 600 dpi. It is even more advantageous if the minimum resolution at which the structure is produced is 800 dpi. It is even more advantageous if the minimum resolution at which the structure is produced is greater than 800 dpi.As the minimum resolution at which the structure is manufactured increases, so does its protection against duplication. This is because, with increasing minimum resolution, the manufacturing process becomes more difficult, ensuring that the structure is designed in such a way that the first unique identification code can be decoded. Furthermore, any attempt to copy the structure will alter it, or rather, falsify it, to such an extent that, especially after a subsequent re-production, decoding is no longer possible.In particular, the fact that the structure is designed as a Fourier pattern ensures a high minimum resolution and thus copy protection. This is achieved by ensuring that, after the structure has been optically captured (e.g., by scanning or photographing) and subsequently reproduced (e.g., by printing it with a standard printer), it is no longer readable in the sense that the first unique identification code cannot be decoded from the reproduced structure. It can then be concluded that the reproduced structure is a copy of the original structure, and consequently, that, for example, a test device with an attached reproduced structure is an unauthorized copy of the test device with the structure that was optically captured during the copying process.In summary, it can be stated that by ensuring that the first unique identification code from the structure can only be decoded if it is manufactured with a minimum resolution, copy protection for the test device can be provided. In particular, by ensuring that the first unique identification code from the structure can only be decoded if it is manufactured with a minimum resolution, it can be guaranteed that a reproduced structure can be traced back to an original structure.

[0013] In a preferred embodiment, reflective coatings can be provided on or next to the structure, making it more difficult to optically detect the structure. In this case, it is provided that when the result field and the safety field are optically detected together, preferably simultaneously, the structure is illuminated with focused light. This further increases safety, since detection of the structure is more difficult with unfocused illumination.

[0014] The structure or information field containing the structure can be printed onto the test device, in particular onto a base body of the test device, for example by means of digital offset printing. Likewise, the structure or information field containing the structure can be printed onto a label, in particular onto a base body of the label, wherein the label has a self-adhesive side and can be bonded to a test device by means of this self-adhesive side. In particular, the bond with the test device ensures that the label is attached to the test device so that the safety field of the label forms the safety field of the test device. Furthermore, the structure or information field containing the structure can also be embossed into the surface of the test device. The structure or information field containing the structure can also be inscribed into the surface of the test device by means of a laser marking process.The markings are burned in. In particular, stamping and laser marking create inseparable bonds between the test fixture and the structure or between the test fixture and the information field with the structure, thus preventing manipulation, such as replacing the structure.When, in connection with the present invention, the following are described: attaching the label to the test device, connecting the label to the test device, printing the structure or information field with the structure onto the test device, stamping the structure or information field with the structure into the surface of the test device, inscribing or burning the structure or information field with the structure into the surface of the test device, this means in particular that the corresponding steps are carried out and, after carrying out the steps, a test device according to the invention is produced.

[0015] Furthermore, the result field and the safety field are arranged such that they can be optically detected together, preferably simultaneously, by a single detection unit. By arranging the result field and the safety field in such a way that they can be optically detected together, preferably simultaneously, by a single detection unit, it is ensured that the result field and the safety field can be optically detected together, preferably simultaneously, and in particular automatically, by a single detection unit.Furthermore, by arranging the result field and the safety field in such a way that they can be optically detected together, preferably simultaneously, by a single detection unit, it is ensured that a test result can be deduced from the optically detected result field, in particular from whether the result field exhibits the first or the second appearance, and from the first unique identification code based on the optically detected safety field. For example, by ensuring that the first unique identification code is encoded within the structure and that the structure can only be decoded if it is manufactured with a minimum resolution, it is possible to deduce an approved test device manufactured by a specific manufacturer and simultaneously to determine a specific test result.Furthermore, the test result and the first unique identification code can be linked. This link allows for further analysis, such as comparing the first unique identification code with stored unique identification codes. Additionally, this link confirms that the test result was obtained using a test device with a structure that is not an unauthorized reproduction. Furthermore, the simultaneous optical capture of the result field and the security field ensures that a single image captures both the test result and the structure, allowing for easy linking within a data set and thus further hindering manipulation.In particular, simultaneous recording, especially by photographing, allows an image of the test result and the structure to be captured in one image and thus "linked" together in a data set, making manipulation of the photographed test result more difficult.

[0016] In summary, it can be stated that the present invention increases the reliability of test results.

[0017] According to the invention, the first unique identification code is a first two-dimensional code, and the structure of the information field is a two-dimensional representation of a binarized Fourier transform of a two-dimensional function representing the first two-dimensional code. Since the structure is a two-dimensional representation of the binarized Fourier transform, the two-dimensional representation can have or be formed from a pattern consisting of black and white pixels. However, the design is not limited to the colors white and black. In particular, any color representation is suitable that exhibits sufficient contrast to distinguish pixels from one another. The two-dimensional representation of the binarized Fourier transform can also be referred to as a Fourier pattern.The first two-dimensional code can be a QR code, a DataMatrix, a Cool DataMatrix, an Aztec, a UPCode, a Trillcode, a Quickmark, a Shotcode, an mCode, or a Beetagg. However, the first two-dimensional code is not limited to any code from this list. As previously described, the first unique identification code can also be a two-dimensional code. Alternatively, the first unique identification code can be a one-dimensional code. The first one-dimensional code can be a Code 39, Code 128, Codebar, Interleaved 2 of 5, UPC, EAN, GS1, or PDF417. However, the first one-dimensional code is not limited to any code from this list.

[0018] In one embodiment, the result field and the safety field are spaced apart. This spacing ensures that additional information can be displayed on the test device between the result field and the safety field.

[0019] In one embodiment, the result field and the safety field are adjacent to each other. This proximity of the result field and the safety field ensures that optical detection of both fields is particularly simple and space-saving.

[0020] In one embodiment, the safety field surrounds the result field. When the safety field surrounds the result field, it is ensured that the safety field can be used as a guide during optical detection, and that the arrangement of the result field can be deduced from the arrangement of the safety field. Furthermore, it can be ensured that the result field is always captured when the safety field is optically detected. This prevents a situation where, for example, a safety field is photographed for verification, but the result field is inadvertently not captured.

[0021] In one embodiment, the information field surrounds the result field. When the information field surrounds the result field, it is ensured that the information field can be used as a guide during optical scanning, and that the arrangement of the result field can be deduced from the arrangement of the information field. Furthermore, it is ensured that the result field is always captured when the information field is optically scanned. This prevents situations where, for example, an information field is photographed for verification, but the result field is inadvertently not captured.

[0022] According to the invention, the security field features a second two-dimensional code. This second two-dimensional code can be a QR code, a DataMatrix, a Cool Data Matrix, an Aztec, a UPCode, a Trillcode, a Quickmark, a Shotcode, an mCode, or a Beetagg. However, the second two-dimensional code is not limited to any code from this list. The second two-dimensional code provides a means of arranging additional information on the test device. Additionally, the security field can feature a second one-dimensional code. This second one-dimensional code can be a Code39, Code 128, Codebar, Interleaved 2 of 5, UPC, EAN, GS1, or PDF417. Again, the second one-dimensional code is not limited to any code from this list. This second one-dimensional code also provides a means of arranging additional information on the test device.The use of the second one-dimensional and / or two-dimensional code, in combination with the structure used to encode the first unique identification code, ensures that the test device has a conventional appearance and that, in the event of unauthorized use or duplication of the test device, the structure is overlooked, thus preventing the copy protection from being readily detected. The second one-dimensional and / or two-dimensional code can, for example, be designed to be readable by all commercially available devices / scanners and, for instance, its data content can refer to a website.

[0023] In one embodiment, a second unique identification code is encoded in the second two-dimensional code. The features, technical effects, and / or advantages described in connection with the first two-dimensional code also apply, at least analogously, to the second two-dimensional code, so a corresponding repetition is omitted here. In particular, the use of both a first unique identification code and a second unique identification code ensures that dual identification of the test device is provided, so that even if either the first unique identification code or the second unique identification code cannot be determined, at least the other unique identification code can be determined.This further increases the reliability of test results, particularly when either the structure or the second two-dimensional code on the test device is damaged, contaminated, or otherwise obscured by external influences. Furthermore, the use of both a first and a second unique identification code ensures that they can be used for different purposes. For example, the first unique identification code could be used to identify the test device within a government agency, and the second unique identification code could be used to identify the test device within a laboratory.In particular, the different unique identification codes can be used for different purposes, such as identification or registration during the use of the testing device by a person being tested, a doctor or in the laboratory, with each purpose being assigned a specific unique identification code.

[0024] In one embodiment, the second two-dimensional code encloses the result field. When the second two-dimensional code encloses the result field, it is ensured that during optical scanning, the second two-dimensional code can be used as a guide, and the arrangement of the result field can be deduced from the arrangement of the second two-dimensional code. Furthermore, it is ensured that when the second two-dimensional code is optically scanned, the result field is always captured as well. This prevents the second two-dimensional code from being captured, for example, by photographing it, while inadvertently missing the result field.

[0025] According to the invention, the structure of the information field forms a section of the second two-dimensional code of the security field. When the structure of the information field forms a section of the second two-dimensional code of the security field, the security of test results is increased, particularly in a space-saving manner. According to a second aspect of the invention, the aforementioned problem is solved by a test device system with the features of claim 5. The test device system comprises several test devices according to the first aspect of the invention.

[0026] The unique identification codes of the test devices differ. The features, technical effects and / or advantages described in connection with the test device according to the first aspect of the invention also apply, at least analogously, to the test device system according to the second aspect of the invention, so that a corresponding repetition is omitted here.

[0027] In one embodiment, the first appearances of the test devices of the test device system differ. If the first appearances of the test devices differ, it can be ensured that a user of a particular test device cannot infer a test result based on the first appearance alone. Rather, it is provided that, for example, the first unique identification code is used to determine which specific test result can be inferred from the specific first appearance present. This can be done, for example, by comparing it with mappings stored in a database of a multitude of first unique identification codes, a multitude of first appearances, and a multitude of second appearances, where each first unique identification code is assigned a first appearance and a second appearance.In particular, the first and second appearances assigned to a specific first unique identification code differ. Specifically, because the first appearances of the test devices within the test device system differ from one another, it can be prevented, for example, that the user attempts to manipulate the first appearance to potentially generate the second appearance and obtain a false test result. The database can also store a patient's personal data, the date and time of the transmission of the unique identification code from the evaluation unit to a server, and the geolocation of the data acquisition unit at the time the result field and the security field were captured, each of which is assigned to a first unique identification code.

[0028] As previously described, the initial appearance of the result field can include a horizontal stripe within a control field of the result field. The differentiation of the initial appearances of the test devices within the test device system can be achieved, for example, by varying the positions of the control fields within the result fields of the test devices. Thus, a user cannot predict the position of the control field in which the horizontal stripe will appear before the stripe itself appears. Therefore, the user cannot definitively infer a specific test result.In particular, if the test device is adapted to determine whether the liquid contains multiple ingredients and each ingredient is assigned a corresponding horizontal stripe in a corresponding control field of the result field, it is advantageous if the positions of the control fields for a specific ingredient differ between the test devices. If a horizontal stripe appears in a specific position in such a test device, the user cannot deduce the ingredient present. Instead, a database is intended to store a set of assignments from a multitude of first unique identification codes, a multitude of first appearances, and a multitude of second appearances.An evaluation using the database can, based on the first unique identification code, deduce the specific test result that can be inferred from the initial appearance of the test. Thus, the actual test result can be determined. The test result cannot be falsified, as the user does not know, based on the testing device, at which position a horizontal line will appear for a particular test result.In particular, if, as already described, both test devices are provided in which the first appearance of the result field has a horizontal stripe in a control field of the result field, and test devices are provided in which the first appearance of the result field does not have the horizontal stripe in the control field of the result field, a user of the test device cannot infer a specific test result without doubt.

[0029] As a third aspect, not covered by the claims, a label is described. The label has a security field. The security field has an information field with a structure. A first unique identification code is encoded in the structure. The identification code can only be decoded from the structure if the structure is manufactured with a minimum resolution. The label is intended to be attached to a test device according to the first aspect of the invention, such that the security field of the label forms the security field of the test device.The features, technical effects and / or advantages described in connection with the test device according to the first aspect of the invention and the features, technical effects and / or advantages described in connection with the test device system according to the second aspect of the invention also apply, at least analogously, to the label according to the third aspect, so that a corresponding repetition is omitted here.

[0030] In one embodiment, the label has a backing layer coated with an adhesive layer, and the security field is arranged on the backing layer. The adhesive layer allows the label to be attached to a test device, thus creating a bond between the label and the test device. The backing layer can be mechanically reinforced, for example, to increase its stiffness. Mechanical reinforcement can also be selected to increase resistance to crack initiation and / or propagation. This can be achieved, for example, by embedding fibers in the backing layer.Furthermore, the label, particularly if it consists of an adhesive layer or an adhesive compound that need not be a single layer but, for example, comprises numerous unconnected adhesive sections, can be designed in such a way that it is damaged when removed from the test device, preventing its reuse on another test device. This can be achieved, for example, by designing the label such that the force required to break the bond when removing it from the test device exceeds the label's maximum load-bearing capacity, causing mechanical failure.

[0031] As a fourth aspect, which is not covered by the claims, a labeling system is described. The labeling system comprises several labels according to the third aspect. The unique identification codes of the labels differ. The features, technical effects, and / or advantages described in connection with the test apparatus according to the first aspect, with the test apparatus system according to the second aspect, and with the label according to the third aspect also apply, at least analogously, to the labeling system according to the fourth aspect, so that a corresponding repetition is omitted here. According to a fifth aspect of the invention, the aforementioned problem is solved by a method with the features of claim 7. The method is adapted to determine whether a liquid contains an ingredient. The method comprises the following steps: common,Preferably, simultaneous optical detection of the result field and the safety field of a test device according to the first aspect of the invention by a detection unit; transmission of the optically detected result field and the optically detected safety field from the detection unit to an evaluation unit; inference of a test result based on the optically detected result field and of the unique identification code based on the optically detected safety field by the evaluation unit; assignment of the test result to the unique identification code by the evaluation unit; comparison of the unique identification code with stored unique identification codes; determination of whether the stored unique identification codes contain the unique identification code; determination, if the stored unique identification codes contain the unique identification code,whether a test result associated with the unique identification code is stored; and, if no associated test result is stored for the unique identification code, the test result associated with the unique identification code is stored. By storing the test result associated with the unique identification code only if no associated test result is stored for the unique identification code, a check is performed to determine whether the first unique identification code has already been used. This ensures that only one test result can be stored for each unique identification code and that this result cannot be subsequently overwritten or changed. The test equipment according to the first aspect, and the test equipment system according to the second aspect,The features, technical effects, and / or advantages described with the label according to the third aspect and with the labeling system according to the fourth aspect also apply, at least analogously, to the method according to the fifth aspect of the invention, so that a corresponding repetition is omitted here. In particular, it is provided that the detection unit is a detection unit of a mobile phone, such as a camera, especially a digital camera, of the mobile phone. Preferably, the evaluation unit is an evaluation unit of a server. However, the evaluation unit can also be an evaluation unit of the mobile phone. In particular, if the evaluation unit is an evaluation unit of the mobile phone, the following steps are preferably carried out server-side, in particular by a server and database: comparing the unique identification code with stored unique identification codes; determining,The system checks whether the stored unique identification codes contain the unique identification code; determines, if the stored unique identification codes contain the unique identification code, whether a test result associated with the unique identification code is stored; and, if no associated test result is stored for the unique identification code, stores the test result associated with the unique identification code. Furthermore, if the evaluation unit is a mobile phone evaluation unit, the test result and the unique identification code are preferably transmitted from the evaluation unit to the server. In this case, the transmission of large camera images to the server can be avoided. Preferably, the server is connected to a database to perform the individual steps of the procedure.

[0032] In one embodiment, the method further includes the following step: issuing a confirmation message when the test result associated with the unique identification code has been saved. The confirmation message informs a user of the test device that the test result has been saved. Since the test result associated with the unique identification code is only saved if no corresponding test result is stored for that unique identification code, it can be inferred that no prior test has been performed with the test device itself or with a test device equipped with a security field containing an information field with a structure encoding an identical first unique identification code.The confirmation message can be used, for example, as proof, also known as a certificate, and presented at border crossings to prevent potential quarantine, which might be mandatory for anyone who cannot demonstrate a high degree of certainty about their test result or even no test result at all. Displaying the confirmation message on a mobile phone is particularly convenient.

[0033] In one embodiment, the method further comprises the following steps: applying a sample of the liquid to the sample field of the test device; and affixing a label to the test device according to the third aspect, such that the security field of the label forms the security field of the test device. One option is to apply the sample first and then affix the label to the test device, so that the label is not yet attached to the test device during sample application. This prevents tampering with the label during sample application. Alternatively, it is also possible to attach the label to the test device first and then apply the sample. Preferably, the label is attached to the test device during its production.It is particularly preferred that the label is affixed after the production of the test device and before the sample is applied to the test device.

[0034] Even though the process steps are described in a specific sequence, the present invention is not limited to this sequence. Rather, the individual process steps can be carried out in any meaningful order, and in particular, at least partially in parallel with one another.

[0035] As a sixth aspect, which is not covered by the claims, a data processing system is described. The data processing system comprises means for carrying out the method according to the fifth aspect of the invention. The features, technical effects, and / or advantages described in connection with the test apparatus according to the first aspect, the test apparatus system according to the second aspect, the label according to the third aspect, the label system according to the fourth aspect, and the method according to the fifth aspect of the invention also apply, at least analogously, to the data processing system according to the sixth aspect, so that a corresponding repetition is omitted here. In one embodiment, the means comprise a mobile phone. In another embodiment, the means comprise a database.

[0036] A computer program is described as the seventh aspect that is not covered by the claims.

[0037] The computer program comprises instructions that, when executed by a computer, cause it to perform the steps of the method according to the fifth aspect of the invention. The features, technical effects, and / or advantages described in connection with the other aspects also apply, at least analogously, to the computer program according to the seventh aspect, so a corresponding repetition is omitted here. In one embodiment, the means comprise a mobile phone. In another embodiment, the means comprise a database. In another embodiment, at least a subset of the instructions are formed by instructions from an app.

[0038] The eighth aspect, which is not covered by the requirements, is described as a computer-readable medium.

[0039] The computer program is stored on the computer-readable medium according to the seventh aspect. The characteristics, technical effects, and / or advantages described in connection with the other aspects also apply, at least analogously, to the computer-readable medium according to the eighth aspect, so a corresponding repetition is omitted here.

[0040] Further features, advantages, and applications of the present invention will become apparent from the following description of the exemplary embodiments and the figures. All features described and / or illustrated, individually and in any combination, constitute the subject matter of the invention, irrespective of their composition in the individual claims or their cross-references. In the figures, the same reference numerals denote identical or similar objects. Figure 1 shows a schematic view of a first embodiment of a test device according to the invention, Figure 2 shows a schematic view of a second embodiment of the test device according to the invention, Figure 3 shows a schematic view of a third embodiment of the test device according to the invention, Figure 4 shows a schematic view of a fourth embodiment of the test device according to the invention, Figure 5 also shows a schematic view of the fourth embodiment of the test device according to the invention, Figure 6 shows a schematic view of a first embodiment of the test device system according to the invention, Figure 7 shows a schematic view of a second embodiment of the test device system according to the invention, Figure 8 shows a schematic view of an embodiment of the label, and Figure 9 shows a schematic sectional view of the Figure 8 illustrated embodiment of the label.

[0041] In Figure 1Figure 1 shows a schematic view of a first embodiment of a test device 1 according to the invention. The test device 1 has a sample field 3, a result field 5, and a security field 7 adjacent to the result field 5. The security field 7 has an information field 9, which in this embodiment is formed by a QR code. A structure 11 is formed in the information field 9, with which a first unique identification code is encoded, which in this embodiment is a first two-dimensional code. The first two-dimensional code is represented by a two-dimensional function. According to the invention, the structure 11 is a two-dimensional representation of a binarized Fourier transform of this two-dimensional function and is formed in the dark areas of the QR code in a manner as shown in the enlarged view and described in more detail below.The security field 7 further comprises a second two-dimensional code 13. In this embodiment, this second two-dimensional code 13 is formed by the QR code as a whole, including the dark and light areas. The QR code has these light and dark areas, the size and arrangement of which, together with the second two-dimensional code 13, encode a second unique identification code.

[0042] To form structure 11, through which the first unique identification code in the form of the first two-dimensional code is encoded, the dark areas of the QR code are not uniformly formed, but exhibit a pattern that appears in the unmagnified view. Figure 1The QR code exhibits an indistinct structure, which is schematically illustrated in the enlarged view. In this embodiment, this structure is formed by white and black sections within the dark areas of the QR code. In this embodiment, the light areas of the QR code are white. However, in other embodiments, the structure can also be formed by sections with different shades of gray or colored within the dark areas of the QR code. Again, in this embodiment, the light areas of the QR code are white. In other embodiments, the structure can be formed by white and black sections within the light areas of the QR code. In this case, the dark areas of the QR code are black. The structure can also be formed in other embodiments by sections with different shades of gray or colored within the light areas of the QR code.In this case too, the dark areas of the QR code are black.

[0043] This structuring in the dark areas of the QR code constitutes structure 11 according to the present invention. Structure 11 thus extends over the dark areas of the second two-dimensional code 13 in the form of the QR code. Structure 11 of the information field 9 therefore forms a section of the second two-dimensional code 13. Furthermore, structure 11 within the dark areas is designed such that it is produced with a resolution of 300 dpi, i.e., there are 300 black or white sections per inch within the dark areas of the QR code. Thus, structure 11 is designed such that, for decoding, for example, optical detection with a minimum resolution of 300 dpi is necessary.Conversely, if structure 11 is produced at a resolution lower than 300 dpi, the first unique identification code cannot be decoded from structure 11, even if it is captured at the correct minimum resolution. Furthermore, it is also conceivable that the resolution at which structure 11 is rendered in the dark areas is higher, for example, 600 dpi or greater than 600 dpi, such as 800 dpi or greater than 800 dpi.

[0044] Furthermore, security field 7 has a third unique identification code 15. The third unique identification code 15 in the Figure 1The illustrated embodiment consists of the character string "NCHGF7LX5L". The security field 7 thus contains the first unique identification code in coded form, the second unique identification code in coded form, which together are formed in the information field 9, and the third unique identification code 15 in non-coded form. In particular, in this embodiment and in other embodiments, the second unique identification code and the third unique identification code can be identical. This ensures that if the second unique identification code cannot be decoded from the second two-dimensional code 13, for example due to damage or contamination, the third unique identification code can be entered manually, for example by typing.

[0045] Since the safety field 7 is adjacent to the result field 5, in this embodiment the result field 5 and the safety field 7 are arranged in such a way that the result field 5 and the safety field 7 can be optically detected together, preferably simultaneously, by a detection unit.

[0046] In Figure 2 Figure 1 shows a schematic view of a second embodiment of the test device 1 according to the invention. The test device 1 has a sample field 3, a result field 5, and a safety field 7 adjacent to and surrounding the result field 5. The safety field 7 has an information field 9 surrounding the result field 5 with a structure 11, which is shown in the non-enlarged view in Figure 1. Figure 2Structure 11 has white or black sections not shown, which are schematically represented in the enlarged view. In this embodiment, structure 11 is formed by white and black sections. However, in other embodiments, structure 11 can also be formed by sections with different shades of gray or by color. A first unique identification code, which is a first two-dimensional code, is encoded in structure 11. The first two-dimensional code is represented by a two-dimensional function. According to the invention, structure 11 is a two-dimensional representation of a binarized Fourier transform of this two-dimensional function.

[0047] Outside of the invention, other possibilities for encoding the first two-dimensional code are conceivable, but the invention is limited to the use of a binarized Fourier transform.

[0048] In this embodiment as well, the structure 11 is designed such that decoding requires, for example, optical detection with a minimum resolution of 300 dpi; thus, the structure is manufactured with a resolution of 300 dpi. Conversely, if the structure 11 is manufactured with a lower resolution than 300 dpi, the first unique identification code cannot be decoded from the structure 11, even if it is detected with the correct minimum resolution. It is also conceivable that the resolution with which the structure 11 is incorporated into the dark areas is higher.

[0049] The security field 7 of the second embodiment has a second two-dimensional code 13. The second two-dimensional code 13 is a DataMatrix code, which allows for a particularly space-saving design of the test device 1. A second unique identification code is encoded in the second two-dimensional code 13. Furthermore, the security field 7 has a third unique identification code 15. The third unique identification code 15 in the Figure 2The illustrated embodiment consists of the string "H3WRTYXD34". The security field 7 thus contains the first unique identification code in coded form, the second unique identification code in coded form, and the third unique identification code 15 in non-coded form. The first unique identification code can be used to verify the authenticity of the test device 1. The second unique identification code can be used in further processing after automatic acquisition of the second two-dimensional code 13. In this embodiment, the third unique identification code 15 is a human-readable code and can be used for manual acquisition.

[0050] The second two-dimensional code 13, which forms the DataMatrix code, is a two-dimensional representation with white and black areas. The black areas of the second two-dimensional code 13 do not exhibit structure 11. Information field 9, which does have structure 11, is positioned at a distance from the second two-dimensional code 13.

[0051] Since in this embodiment the safety field 7 or the information field 9 surrounds the result field 5, in this embodiment the result field 5 and the safety field 7 are arranged in such a way that the result field 5 and the safety field 7 can be optically detected together, preferably simultaneously, by a detection unit.

[0052] In Figure 3Figure 1 shows a schematic view of a third embodiment of the test device 1 according to the invention. The test device 1 has a sample field 3, a result field 5, and a safety field 7 adjacent to and surrounding the result field 5. The safety field 7 has an information field 9 surrounding the result field 5, which in this embodiment is also formed by a QR code. In the dark areas of the QR code, a structure 11 is formed such that these dark areas are in Figure 3The structure is not shown and is composed of white and black sections. Here too, structure 11 is designed such that decoding requires, for example, optical scanning with a minimum resolution of 300 dpi; therefore, the structure itself is produced at a resolution of 300 dpi. Conversely, if structure 11 is produced at a lower resolution than 300 dpi, the first unique identification code cannot be decoded from structure 11, even if it is scanned at the correct minimum resolution. It is also conceivable that the resolution at which structure 11 is applied to the dark areas is higher.

[0053] This structure 11 encodes a first unique identification code, which in this embodiment is also a first two-dimensional code. The first two-dimensional code is represented by a two-dimensional function.

[0054] According to the invention, structure 11 is a two-dimensional representation of a binarized Fourier transform of this two-dimensional function.

[0055] Security field 7 also features a second two-dimensional code 13 surrounding result field 5, which is formed by the QR code itself. This second two-dimensional code 13 encodes a second unique identification code. Security field 7 thus contains both the first unique identification code in encoded form and the second unique identification code in encoded form.

[0056] The second two-dimensional code 13 forming the QR code is a two-dimensional representation with white and dark areas. The dark areas of the second two-dimensional code 13 exhibit structure 11. Structure 11 extends over the dark areas of the second two-dimensional code 13. Structure 11 of the information field 9 thus forms a section of the second two-dimensional code 13. In this embodiment, the dark areas of the second two-dimensional code 13 exhibit structure 11. In other embodiments, however, the white areas of the second two-dimensional code 13 could also exhibit structure 11, in which case the white areas could be referred to as light areas.Since in this embodiment the safety field 7 surrounds the result field 5, in this embodiment the result field 5 and the safety field 7 are again arranged in such a way that the result field 5 and the safety field 7 can be optically detected together, preferably simultaneously, by a detection unit.

[0057] In Figure 4 and Figure 5 Each figure shows a schematic view of a fourth embodiment of the test device 1 according to the invention. The fourth embodiment corresponds essentially to the first embodiment, except that the first unique identification code, the second unique identification code, and the third unique identification code 15, which consists of the string "29F3KL", differ in the fourth embodiment from the first unique identification code, the second unique identification code, and the third unique identification code 15 of the first embodiment.

[0058] The fourth embodiment of the test device 1 according to the invention comprises a sample field 3, a result field 5, and a safety field 7 adjacent to the result field 5. The safety field 7 further comprises an information field 9, which in this embodiment is also formed by a QR code. In the dark areas of the QR code, a structure 11 is formed such that the dark areas in Figures 4 and 5The structure 11 is composed of black and white sections, as not shown. Here too, structure 11 is designed such that decoding requires, for example, optical detection with a minimum resolution of 300 dpi; therefore, the structure is manufactured with a resolution of 300 dpi. Conversely, if structure 11 is manufactured with a lower resolution than 300 dpi, the first unique identification code cannot be decoded from structure 11, even if it is detected with the correct minimum resolution. It is also possible that the resolution with which structure 11 is applied to the dark areas is higher. A first unique identification code is encoded in this structure 11, which, in this embodiment as well, is a first two-dimensional code. The first two-dimensional code is represented by a two-dimensional function.According to the invention, structure 11 is a two-dimensional representation of a binarized Fourier transform of this two-dimensional function.

[0059] Security field 7 also features a second two-dimensional code 13, which is formed by the QR code itself. This second two-dimensional code 13 encodes a second unique identification code. Security field 7 thus contains both the first unique identification code in encoded form and the second unique identification code in encoded form.

[0060] In addition, the safety field 7 of the fourth embodiment of a test device according to the invention has a third unique identification code 15, which consists of the string "29F3KL".

[0061] In this embodiment, the safety field 7 borders the result field 5, so that in this embodiment as well the result field 5 and the safety field 7 are arranged in such a way that the result field 5 and the safety field 7 can be optically detected together, preferably simultaneously, by a detection unit.

[0062] The following describes, using the fourth embodiment as an example, the design of the first, second, third and fourth embodiments, which makes it possible to determine with the test device 1 according to the invention whether a liquid contains an ingredient.

[0063] A sample of liquid, such as blood, can be applied to sample field 3. In the Figures 4 and 5Sample field 3 is shown in black, symbolizing a liquid applied to it. The liquid sample may contain a substance, such as immunoglobulin G or immunoglobulin M, in at least a minimum quantity. Alternatively, the sample may not contain the substance in at least the minimum quantity, for example, if the sample does not contain the substance. Result field 5 is designed to display a first appearance if the sample contains the substance in at least the minimum quantity, and a second appearance if the sample does not contain the substance in at least the minimum quantity.

[0064] When the liquid sample was applied to sample field 3, it appears as shown in Figures 4 and 5A horizontal stripe is displayed in a first control field 17 of the result field 5 both when the sample contains the ingredient in at least the minimum quantity and when the sample does not contain the ingredient in at least the minimum quantity. The appearance of this horizontal stripe in the first control field 17 indicates that the test device 1 is functioning correctly. Thus, both the first and second versions of the result field exhibit the horizontal stripe in the first control field 17. In another embodiment, the horizontal stripe in the first control field 17 of the result field 5 can also be displayed before the liquid sample is applied to the sample field 3.This horizontal stripe in the first control field 17 of the result field 5 is therefore always visible and ensures that a user of the test device can recognize what a horizontal stripe looks like when it appears, so that the user can clearly compare whether a line has become visible or not. The horizontal stripe in the first control field 17 is often labeled "C" and can also be referred to as "Control".

[0065] Furthermore, if the liquid sample is applied to sample field 3 and contains immunoglobulin G (IgG) in at least the minimum required quantity, a horizontal line will appear in a second control field 19 of result field 5. The appearance of this horizontal line in the second control field 19 indicates the presence of immunoglobulin G in at least the minimum required quantity. Conversely, if the liquid sample is applied to sample field 3 but does not contain immunoglobulin G in at least the minimum required quantity, no horizontal line will appear in the second control field 19 of result field 5. The absence of this horizontal line in the second control field 19 indicates the presence or absence of immunoglobulin G, or the presence of immunoglobulin G in a quantity not met.With regard to immunoglobulin G, the first appearance of result field 5 shows the horizontal stripe in the second control field 19. With regard to immunoglobulin G, the second appearance of result field 5 does not show the horizontal stripe in the second control field 19. With regard to immunoglobulin G, the appearance of result field 5 can therefore be described as follows: Figure 4 can be described as the second form of appearance and the form of appearance of result field 5 in Figure 5 can be described as the first manifestation.

[0066] Furthermore, if the liquid sample is applied to sample field 3 and contains immunoglobulin M (IgM) in at least the minimum required quantity, a horizontal line will appear in a third control field 21 of result field 5. The appearance of this horizontal line in the third control field 21 indicates the presence of immunoglobulin M in at least the minimum required quantity. Conversely, if the liquid sample is applied to sample field 3 but does not contain immunoglobulin M in at least the minimum required quantity, no horizontal line will appear in the third control field 21 of result field 5. The absence of this horizontal line in the third control field 21 indicates the absence or presence of immunoglobulin M in a quantity not met.With regard to immunoglobulin M, the first appearance of result field 5 shows the horizontal stripe in the third control field 21. With regard to immunoglobulin M, the second appearance of result field 5 does not show the horizontal stripe in the third control field 21. With regard to immunoglobulin M, the appearance of result field 5 can therefore be described as follows: Figure 4 can be described as the second form of appearance and the form of appearance of result field 5 in Figure 5 can be described as the first manifestation.

[0067] Test device 1 can thus determine whether a liquid, such as blood, contains a component such as immunoglobulin G or immunoglobulin M. In particular, test device 1 can determine whether the liquid contains two components, namely immunoglobulin G and immunoglobulin M. Based on these two components, the appearance of result field 5 can be determined. Figure 4 can be described as the second form of appearance and the form of appearance of result field 5 in Figure 5 can be described as the first manifestation.

[0068] For the first, second, third, and fourth embodiments, as already described, the first unique identification code is encoded in the structure 11 of the information field 9. The first unique identification code can only be decoded from the structure 11 if the structure 11 is manufactured with a minimum resolution. If the structure 11 is manufactured with a resolution lower than the minimum resolution, the unique identification code cannot be decoded from the structure 11, since in this case the information necessary for decoding is not contained in the structure 11.

[0069] The result field 5 and the safety field 7 are arranged as explained above in such a way that the result field 5 and the safety field 7 can be optically detected together, preferably simultaneously, by a detection unit.

[0070] In Figure 6Figure 1 shows a schematic view of a first embodiment of the test device system 23 according to the invention. The test device system 23 comprises several test devices 1 according to the first, second, third, or fourth embodiment. The first unique identification codes of the test devices 1 differ. Furthermore, the second unique identification codes of the test devices 1 differ. Finally, the third unique identification codes 15 of the test devices 1 also differ. With regard to the two ingredients immunoglobulin G and immunoglobulin M, the appearance of the result field 5 can be seen in Figure 6The first appearances of the test devices 1 of the first embodiment of the test device system 23 are identical. For example, the test devices 1 of the first embodiment of the test device system 23 are manufactured in a first batch. In particular, the arrangement of the first, second, and third control fields 17, 19, 21 within the first batch of the test device system 23 is the same. However, it is also conceivable that the first appearances of the test devices 1 differ.

[0071] In Figure 7Figure 1 shows a schematic view of a second embodiment of the test device system 23 according to the invention. The test device system 23 comprises several test devices 1 according to the first, second, third, or fourth embodiment. The first unique identification codes of the test devices 1 differ. Furthermore, the second unique identification codes of the test devices 1 differ. Finally, the third unique identification codes 15 of the test devices 1 also differ. With regard to the two ingredients immunoglobulin G and immunoglobulin M, the appearance of the result field 5 can be seen in Figure 7The first appearances of the test devices 1 of the second embodiment of the test device system 23 are identical. The test devices 1 of the second embodiment of the test device system 23 are, for example, manufactured in a second batch. In particular, the arrangement of the first, second, and third control fields 17, 19, 21 within the second batch of the test device system is the same. However, it is also conceivable that the first appearances of the test devices 1 differ. For example, the test device system 23 can produce test devices 1 with the first appearance according to Figure 6 as well as test devices 1 with the first appearance according to Figure 7exhibiting such that a user of the test device 1 cannot predict, before applying the liquid sample to the sample field 3, how the stripes of the first appearance 1 of the result field 5 are arranged in the result field 5. The test devices 1 can be manufactured in a multitude of batches, the arrangement of the first, second, and third control fields 17, 19, 21 of the batches differing from one another, so that it is not apparent to a user of a particular test device 1 what the actual test result is. Rather, the user is dependent on inferring a specific test result based on an association between the first unique identification code and an initial appearance. Figure 8Figure 1 shows a schematic view of an embodiment of the label 25. The label 25 is intended to be attached to a test device 1 according to the third embodiment, such that the safety field 7 of the label 25 forms the safety field 7 of the test device 1.

[0072] The label 25 has a security field 7, which in turn comprises an information field 9. In this embodiment, the information field 9 is also formed by a QR code. In the dark areas of the QR code, a structure 11 is formed such that these dark areas are Figure 8The structure 11 is composed of black and white sections, as not shown. Here too, structure 11 is designed such that decoding requires, for example, optical detection with a minimum resolution of 300 dpi; therefore, the structure is manufactured with a resolution of 300 dpi. If structure 11 is manufactured with a lower resolution than 300 dpi, the first unique identification code cannot be decoded from structure 11. It is also possible that the resolution with which structure 11 is applied to the dark areas is higher. A first unique identification code is encoded in this structure 11, which, in this embodiment as well, is a first two-dimensional code. The first two-dimensional code can be represented by a two-dimensional function.In this embodiment as well, structure 11 is a two-dimensional representation of a binarized Fourier transform of this two-dimensional function. The security field 7 also features a second two-dimensional code 13, which is formed by the QR code itself. This second two-dimensional code 13 encodes a second unique identification code. Thus, the security field 7 contains both the first unique identification code in encoded form and the second unique identification code in encoded form.

[0073] The second two-dimensional code 13, which forms the QR code, is a two-dimensional representation with white and dark areas. The dark areas of the second two-dimensional code 13 exhibit structure 11. Structure 11 extends across the dark areas of the second two-dimensional code 13. Structure 11 of information field 9 thus forms a section of the second two-dimensional code 13.

[0074] The label 25 has a first recess 27 which ensures that when the label 25 is attached to the test device 1, the sample field 3 of the test device 1 (see Figure 3 ) is exposed so that a sample of the liquid can be applied to the sample field 3. Furthermore, the label 25 has a second recess 29 which ensures that when the label 25 is attached to the test device 1, the result field 5 of the test device 1 (see Figure 3) is exposed in such a way that the result field 5, in particular the first control field 17, the second control field 19 and the third control field 21, is exposed in such a way that the result field 5, in particular the first control field 17, the second control field 19 and the third control field 21, can be optically detected by a detection unit.

[0075] In Figure 9 is a schematic sectional view of the in Figure 8The illustrated embodiment of the label 25 is shown. The label 25 has a carrier layer 33 coated with an adhesive layer 31. The security field 7 is arranged on the carrier layer 33. The adhesive layer 31 allows the label 25 to be attached to a test device 1, thus creating a material-bonded connection between the label 25 and the test device 1. In this embodiment, the carrier layer 33 and the adhesive layer 31 are designed such that the label 25 is destroyed upon removal. This can be achieved, for example, by providing an adhesive adapted to the substrate and / or a security perforation or multiple security perforations in the label.

[0076] Several labels 25 of the embodiment of label 25 can together form a label system. In the label system, the first unique identification codes of the labels 25 differ. Likewise, the second unique identification codes of the labels 25 differ.

[0077] As already described, the test device 1 according to the first, second, third, and fourth embodiments can be used to determine whether a liquid contains an ingredient. The test device 1 can thus be used in an embodiment of a method for determining whether a liquid contains an ingredient. This embodiment of a method comprises the following steps: affixing a label 25 to the test device 1 such that the safety field 7 of the label 25 forms the safety field 7 of the test device 1; applying a sample of the liquid to the sample field 3 of the test device 1; jointly, preferably simultaneously, optically detecting the result field 5 and the safety field 7 of the test device 1 by a detection unit; transmitting the optically detected result field 5 and the optically detected safety field 7 from the detection unit to an evaluation unit.The evaluation unit infers a test result based on the optically detected result field 5 and the first unique identification code based on the optically detected security field 7; the evaluation unit assigns the test result to the first unique identification code; the evaluation unit compares the first unique identification code with stored unique identification codes; it determines whether the stored first unique identification codes contain the first unique identification code; if the stored first unique identification codes contain the first unique identification code, it determines whether a test result associated with the first unique identification code is stored; if no test result associated with the first unique identification code is stored, it stores the test result associated with the first unique identification code.and issuing a confirmation message when the test result associated with the first unique identification code has been saved.

[0078] The procedure described here is executed by means of a data processing system. Furthermore, a computer program is provided, which includes instructions that, when executed by a computer, cause it to carry out the steps of the procedure. A computer-readable medium is also provided on which the computer program is stored.

[0079] It should be further noted that "having" does not exclude any other elements or steps, and "a" or "an" does not exclude a plurality. It should also be noted that features described with reference to one of the above embodiments may also be used in combination with other features of other embodiments described above. Reference numerals in the claims are not to be considered as a limitation. Reference sign

[0080] 1 Test device 3 Sample field 5 Result field 7 Safety field 9 Information field 11 Structure 13 Second two-dimensional code 15 Third unique identification code 17 First control field 19 Second control field 21 Third control field 23 Test device system 25 Label 27 First recess 29 Second recess 31 Adhesive layer 33 Carrier layer

Claims

1. Test device (1) for determining whether a liquid has a substance, having a sample field (3) to which a sample of the liquid can be applied, having a result field (5) which is configured to take on a first appearance when the sample contains the substance in at least a minimum quantity, and to take on a second appearance when the sample does not contain the substance in at least the minimum quantity, and having a security field (7) having an information field (9) having a structure (11), with which a first unique identification code is encoded, wherein the first unique identification code can only be decoded from the structure (11) when this is produced with a minimum resolution, wherein the result field (5) and the security field (7) are arranged in such a way that joint, preferably simultaneous, optical detection of the result field (5) and the security field (7) by a detection unit can occur, wherein the first unique identification code is a first two-dimensional code, characterised in that the structure (11) of the information field (9) is a two-dimensional depiction of a binary coded Fourier transform of a two-dimensional function representing the first two-dimensional code, and wherein the security field (7) has a second two-dimensional code (13) and wherein the structure (11) of the information field (9) forms a section of the second two-dimensional code (13) of the security field (7).

2. Test device (1) according to claim 1, wherein the result field (5) and the security field (7) are spaced apart from each other or wherein the result field (5) and the security field (7) border each other.

3. Test device (1) according to one of the preceding claims, wherein the security field (7) encloses the result field (5), and / or wherein the information field (9) encloses the result field (5).

4. Test device (1) according to one of the preceding claims, wherein a second unique identification code is encoded with the second two-dimensional code (13), and / or wherein the second two-dimensional code (13) encloses the result field (5).

5. Test device system (23) having several test devices (1) according to one of the preceding claims, wherein the first unique identification codes of the test devices (1) differ.

6. Test device system (23) according to claim 5, wherein the first appearances of the test devices (1) differ.

7. Method for determining whether a liquid has a substance, wherein the method comprises the following steps: jointly, preferably simultaneously, optically detecting the result field (5) and the security field (7) of a test device (1) according to one of claims 1 to 6 by a detection unit, transmitting the optically detected result field (5) and the optically detected security field (7) from the detection unit to an evaluation unit, deducing, by the evaluation unit, a test result using the optically detected result field (5) and the first unique identification code using the optically detected security field (7), assigning the test result to the first unique identification code by the evaluation unit, comparing the first unique identification code with a stored unique identification code, determining whether the stored first unique identification codes have the unique identification code, determining whether a test result assigned to the first unique identification code is stored when the stored first unique identification codes have the first unique identification code, and storing the test result assigned to the first unique identification code when no test result assigned to the first unique identification code is stored.

8. Method according to claim 7, wherein the method further comprises the following step: output of an actuation message, when the test result assigned to the first unique identification codes has been stored, and / or wherein the method further comprises the following steps: applying a sample of the liquid to the sample field (3) of the test device (1), and applying a label (25) according to one of claims 7 or 8 to the test device (1) so that the security field (7) of the label (25) forms the security field (7) of the test device (1).