METHOD FOR CONTACTLESS CHARACTERIZATION OF A SUBSTANCE

Description

[0001] The present invention relates to a method for the contactless or non-destructive characterization and / or examination of a substance using waves, in particular electromagnetic waves, according to the preamble of the independent method claim. Furthermore, the invention relates to a corresponding measuring device according to the preamble of the independent device claim. Furthermore, the invention relates to a corresponding computer program product according to the independent product claim. Furthermore, the invention relates to a use of a corresponding measuring device according to the independent use claim.

[0002] Waves (W) altered or emitted by matter can contain information about the matter. The goal of non-contact measurement methods such as quantitative spectroscopy, especially absorption spectroscopy, is to obtain specific information about matter or a specific substance by examining the waves. During the analysis, the information is extracted from a spectral structure of the waves, which consists, for example, of the intensities at different wavelengths.

[0003] In practice, it is problematic that in a measurement of the spectral structure of waves, the information and thus the known spectral structure can be mixed with further information and thus spectral interference structures, which make it difficult to extract the desired information from the measurement. The interference structures can be caused, for example, by other material in the measurement path, by interference from a container, or by the source of the waves themselves.

[0004] A well-known technical solution to the problem is the recording and processing of two measurements taken under different measurement conditions, where the measurements differ only in the extent of the desired information and where the information for one of the two measurements is known. In this way, mathematical methods, such as subtracting the two measurements, can be used to isolate the familiar spectral structure, from which the information can then be derived. The additional measurement with known information is also called a blank, background or reference measurement. Information about the substance can concern properties such as temperature, pressure or chemical composition and is also simply referred to as properties in this document.

[0005] The reference measurement method is obviously only useful when the measurement conditions allow only the information to be varied. In practice, this is achieved, for example, by first performing a reference measurement on an empty container, such as a cuvette without any substance. The known information for this measurement is then literally "substance is not present." The substance is then poured into the container and the actual measurement is performed. After processing the two measurements, e.g., by subtraction, a spectral structure freed of interfering structures is available, from which the information about the added substance can be read. In the field use of non-contact measurement methods, this method is often only applicable to a limited extent, e.g., when the substance is in a sealed container and measurements therefore always contain information about the container.

[0006] To simplify the reading of information from the spectral structure, a mathematical model is often available in practice as a characteristic map, which is compared with the recorded spectral structure using, for example, the least squares (LS) method. For more difficult measuring conditions, such as the measurement of a substance in a sealed container, methods such as the one known from patent EP 2 108 115 B1 exist. Here, in addition to the characteristic map of the spectral structure, characteristic maps for the spectral interference structures are also modeled, which together simplify the reading of information from the measurements. Although these methods can improve the accuracy of the information read, they require precise modeling of the interference structures. This has the considerable disadvantage that unexpected interference structures not provided for in the characteristic map can greatly reduce the accuracy of the information read.Unexpected interference structures can occur, for example, during the non-destructive examination of a soft drink contained in a sealed PET bottle.

[0007] US Pat. No. 5,121,337 A discloses a method for the contactless characterization of a substance using electromagnetic waves, wherein the substance has a spectral structure as a characteristic map that qualitatively depends on at least one property of the substance. The spectral structure is recorded by a measurement, and the measurement may contain one or more interference spectra depending on the measurement conditions. At least two different measurements are performed under different measurement conditions, which may have quantitatively and / or qualitatively different interference spectra and possibly quantitatively different spectral structures. A correction matrix is ​​formed, with the aid of which corrected spectra are generated that no longer contain any interference structure.

[0008] The patent US 6,415,233 B1 relates to a method for measuring the pressure and concentration of a gas in a closed container. A background spectra database is used to account for the container's influence.

[0009] The object of the present invention is to provide an improved method for the contactless or non-destructive characterization and / or testing of a substance using waves, in particular electromagnetic waves. In particular, the object of the present invention is to provide a method which can be carried out simply and conveniently and which delivers precise and reliable results in the characterization and / or testing of the substance. The method according to the invention is intended to be suitable in particular for the quality control of beverages, preferably carbonated beverages which can be held in sealed containers, in order to determine a pressure and / or a carbon dioxide concentration of the beverages, preferably without destroying and / or opening the containers. Furthermore, the object of the present invention is to provide a corresponding measuring device.Furthermore, the object of the present invention is to provide a corresponding computer program product.

[0010] To achieve this object, a method for the contactless or non-destructive characterization and / or examination of a substance using waves, in particular electromagnetic waves, is proposed, having the features of the independent method claim, in particular from the characterizing part. Furthermore, to achieve the object, the invention provides a corresponding measuring device having the features of the independent device claim, in particular from the characterizing part. Furthermore, the invention provides a corresponding computer program product according to the independent product claim. In addition, the invention provides a use of a corresponding measuring device according to the independent use claim. Preferred developments of the invention are listed in the dependent claims. Features disclosed for the individual aspects of the invention can be combined with one another in such a way that, with regard tothe disclosure of the inventive aspects of the invention always refers to each other.

[0011] The invention provides a method for the contactless (with respect to the substance) or non-destructive (with respect to the container) characterization (which substance?) and / or examination (what properties does the substance have?) of a substance. The substance can, for example, be in the form of a gas, which can be located, for example, above a carbonated beverage in a sealed container. The method according to the invention is carried out contactlessly with respect to the substance, although it is of course conceivable for a measuring device to touch the container. The method according to the invention is also carried out non-destructively with respect to the container, i.e. without destroying and / or without opening the container. The characterization serves to determine the type of substance and the examination serves to determine the properties of the substance.

[0012] The process is carried out using waves, preferably electromagnetic waves. The substance exhibits a spectral structure as a characteristic field, which qualitatively depends on at least one property of the substance. A property of the substance refers to a chemical (composition) and / or thermodynamic property (pressure, concentration).

[0013] The spectral structure of the substance is recorded by a measurement. The measurement may exhibit an interfering structure that depends on the measurement conditions. The interfering structure can be caused, for example, by the shape of the container, by other substances in the measurement path, by the measurement conditions and / or by the source of the waves. The measurement conditions can be determined by different measurement angles and / or positions of a measuring device relative to the container in which the substance is held, so that under different measurement conditions the interfering structure can change quantitatively and / or qualitatively and the spectral structure can change quantitatively (e.g., by changing the optical path length). The measurement conditions cause the spectral structure of the substance to be superimposed by the interfering structure in a measurement. In contrast to the spectral structure, which is present as a characteristic map, no function is known for the interfering structure.

[0014] The invention provides that in step 1) at least two different measurements are carried out under different measuring circumstances, which may have quantitatively and / or qualitatively different interference structures and possibly quantitatively different spectral structures, and that in step 2) coefficients of a linear combination of the different measurements and the value of the at least one property of the substance are optimized so that the deviation between the linear combination and the spectral structure is minimized.

[0015] In other words, the invention provides that in step 1) any number of, but at least two, different measurements are carried out under (deliberately) different measuring circumstances, so that the information about the substance and the information about the remaining influencing factors, ie the interfering structures, are represented to different degrees in the individual measurements.

[0016] The invention therefore proposes a method with the features of the independent method claim, in particular from the characterizing part, with which spectral interference structures can be precisely separated from the spectral structures of the substance without their prior modeling. The method can be seen as an extension of the reference measurement method described above. Instead of performing exactly one reference measurement and exactly one further measurement, for which information is partially available, any number of measurements, but at least two, are performed under different measuring conditions, whereby no information needs to be available for the measurements. Measurement conditions can be, for example, measurement angles and / or measurement positions in relation to the substance. To illustrate this, a user can move a measuring device past the substance in different positions and orientations, similar to a barcode scanner, e.g.in the area of ​​a bottle top when a carbonated beverage is examined in a sealed container. In the measurements recorded in this way, information about the substance and other information, such as the container, are each expressed differently. Since it is unknown which measurements contain which information, individual measurements cannot be specifically designated for subtraction, as is the case with the reference measurement method.

[0017] Therefore, the next step of the procedure determines how the measurements can be subtracted to obtain a spectral structure of the substance. The goal is to minimize the deviation of the subtraction result from the spectral structure map. In other words, the coefficients of a linear combination of the various measurements and the read information are optimized so that the deviation between the linear combination and the spectral structure is minimized. After optimization, the read information reflects the actual information with high accuracy.

[0018] The idea behind the invention is that with an increasing number of measurements, the spectral structure of the substance in the Q-dimensional vector space of the measurements will be distinguishable from the interfering structures, where Q is the number of measurement channels. To determine the spectral structure of the substance, in step 2) a relevant subspace of the vector space can first be found in which the measurements mainly take place. The relevant subspace is at most the space spanned by the measurement vectors themselves. The approach is now to rediscover the spectral structure of the substance in the relevant subspace using the characteristic map for the spectral structure of the substance. This is done mathematically by determining the intersection between the characteristic map of the spectral structure of the substance and the relevant subspace. For example,The intersection of the substance's spectral structure with the shortest distance to the relevant subspace can be determined using LS methods. In this way, the substance's spectral structure can be reconstructed from the measured values. Once the substance's spectral structure has been characterized or determined, the substance's property to be determined can be inferred from the spectral structure, such as the pressure and / or carbon dioxide concentration of the substance, which may be present, for example, in the form of a carbonated beverage.

[0019] In the method described above, the measurement vectors do indeed span the relevant subspace, but do not represent a suitable basis for optimization, particularly with a large number of measurements. Therefore, in a method for the contactless characterization of a substance, the invention can provide that in step 2) for, in particular indirectly, optimizing the coefficients of a linear combination of the measurements, coefficients of a linear combination of singular vectors are optimized, wherein the singular vectors are columns of a singular matrix, wherein the singular matrix results from a singular value decomposition of a measurement data matrix, and wherein the measurement data matrix contains the measurements in the columns. Thus, in step 2), data preparation can take place in order to simplify the optimization within the meaning of the invention and reduce computing resources.

[0020] Furthermore, in a method for the contactless characterization of a substance, the invention can provide that the at least two different measurements are carried out at different measuring angles and / or positions relative to a container in which the substance is located. This offers the advantage that the method can be carried out simply and conveniently. For this purpose, a user can move a measuring device past the substance in different positions and orientations, similar to a barcode scanner, for example, in the area of ​​a bottle head when examining a carbonated beverage in a sealed container. In contrast to known methods in which the measuring device must not be moved for a certain time, e.g., for at least 10 seconds, the measuring device according to the invention can be moved simply and conveniently. This appears to be intentional noise in the measurements.However, the resulting variance, together with the method according to the invention, ultimately leads to considerably more accurate measured values ​​than in known methods.

[0021] Furthermore, in a method for the contactless characterization of a substance, the invention can provide that the at least two different measurements are carried out at different measuring angles and / or positions relative to a bottle head of a bottle containing a carbonated beverage, wherein the substance forms a content of the bottle head of the bottle above the carbonated beverage in the bottle. Thus, the contents of the bottle above the carbonated beverage can be characterized and / or examined. A gas forms above the carbonated beverage, which gas, in the normal state or in a sealed bottle, is in thermodynamic equilibrium with the carbonated beverage. Once the gas has been characterized, conclusions can be drawn about the pressure and / or carbon dioxide concentration of the gas and thus of the carbonated beverage.To characterize the gas, electromagnetic waves are preferably used, which can cause the gas molecules to oscillate and / or rotate through absorption in the gas. The electromagnetic waves can have a wavelength between 800 nm and 16 µm, for example, approximately 2400 nm.

[0022] Furthermore, in a method for the contactless characterization of a substance, the invention can provide that, in step 1), a plurality of measurements, preferably up to 80 measurements, are performed under different measurement conditions. In this way, the Q-dimensional vector space can be filled with up to 80 measurements, through which a suitable subspace can be found to characterize the substance.

[0023] Furthermore, in a method for the contactless characterization of a substance, the invention can provide that, in step 1), a plurality of measurements are performed over a period of up to 5 seconds, preferably 10 seconds, preferably 20 seconds. This ensures that a sufficient number of measurements are recorded, which in each case include measurements containing information about the substance.

[0024] Furthermore, in a method for the contactless characterization of a substance, the invention can provide that in step 1) the at least two different measurements are carried out using electromagnetic waves with a wavelength between 800 nm and 16 µm, in particular approximately 2400 nm. Thus, a simple laser measuring device, e.g. in the form of a laser diode, can be used to carry out the method according to the invention. The approximately suitable wavelength can advantageously be selected using the characteristic map if it is known which substance is involved and / or which properties the substance may approximately have. When checking the shelf life of a carbonated beverage, one knows, for example, which pressure and / or which carbon dioxide concentration can be assigned to a long-life beverage.For different values ​​of pressure and / or carbon dioxide concentration, the characteristic map reveals different spectral structures for the substance. This allows an approximately suitable wavelength to be selected to examine the substance using the method according to the invention. Finally, the correct spectral structure for the substance is found as an intersection with the relevant subspace of the measurements. The spectral structure found for the substance corresponds to a specific pressure and / or concentration, which are now determined according to the invention.

[0025] Furthermore, in a method for the contactless characterization of a substance, the invention can provide that in step 1), the at least two different measurements are carried out using an optical method, in particular using a spectroscopic method, preferably an absorption spectroscopic method, preferably a rovibrational spectroscopic method. In particular, when characterizing a substance in the form of a carbonated beverage contained in a sealed container, such a spectroscopic method can be advantageous for generating an absorption spectrum of a gas above the carbonated beverage. In principle, however, it is also conceivable that the method can be carried out using acoustic waves.

[0026] Furthermore, it is conceivable that in step 1), the at least two different measurements are performed using a laser measuring device, in particular a laser diode. A laser measuring device, in particular in the form of a laser diode, is an easy-to-use and cost-effective measuring device that can deliver improved measurement results when performing the method according to the invention.

[0027] Furthermore, in a method for the contactless characterization of a substance, the invention can provide that, in step 2), for the purpose of, in particular indirectly, optimizing the coefficients of a linear combination of the measurements, coefficients of a linear combination of singular vectors are optimized. The singular vectors are columns of a singular matrix. The singular matrix results from a singular value decomposition of a measurement data matrix, and the measurement data matrix contains the measurements in the columns. Thus, data preparation can take place in step 2) to simplify the optimization within the meaning of the invention and reduce computing resources.

[0028] Furthermore, in a method for the contactless characterization of a substance, the invention can provide that, in a step 3), the value of at least one property of the substance is determined by means of the spectral structure, the deviation of which from the linear combination of the various measurements is minimized, wherein, in particular, the value of the at least one property of the substance forms a pressure and / or a carbon dioxide concentration of a carbonated beverage. In this way, the interesting and / or essential properties of the substance can be determined. With the aid of such properties, the quality, shelf life, and / or expiration date of the substance can be determined. Thus, the method according to the invention can be carried out for the quality control of foodstuffs, in particular beverages, preferably carbonated beverages.

[0029] Furthermore, in a method for the contactless characterization of a substance, the invention can provide that, in step 4), a characteristic map for the spectral structure is updated using the spectral structure whose deviation from the linear combination of the various measurements is minimized. In this way, the characteristic map can be kept constantly up-to-date, which can contribute to improving future investigations.

[0030] Furthermore, the object of the invention is achieved by a measuring device for the contactless characterization of a substance using waves, in particular electromagnetic waves. For this purpose, the invention provides that the measuring device is specifically designed to carry out the method according to the invention, which can proceed as described above. The measuring device according to the invention achieves the same advantages as those described above in connection with the method according to the invention. These advantages are incorporated herein by reference in their entirety.

[0031] Within the scope of the invention, it is conceivable that the measuring device can comprise a computer unit designed to optimize the coefficients of a linear combination of the various measurements and the value of at least one property of the substance in order to minimize the deviation between the linear combination and the spectral structure. This allows the substance to be precisely determined.

[0032] In addition, or instead, it is conceivable that the measuring device can have a computer unit designed to optimize, in particular indirectly, the coefficients of a linear combination of the measurements. The singular vectors are columns of a singular matrix. The singular matrix results from a singular value decomposition of a measurement data matrix, and the measurement data matrix contains the measurements in the columns. Thus, the computing power required to carry out the method according to the invention can be reduced. At the same time, a high degree of accuracy of the examination can be ensured.

[0033] Advantageously, the measuring device can comprise a display unit designed to display the spectral structure, whose deviation from the linear combination of the various measurements is minimized, and / or the determined value of at least one property of the substance. Consequently, the measuring device can be operated with a high degree of comfort and almost intuitively, even by an untrained user.

[0034] Furthermore, the object of the invention is achieved by a computer program product that can be stored in a memory of a measuring device, which can be designed as described above, and which, when at least partially implemented in a computer unit of the measuring device, can carry out a method that can run as described above. The computer program product according to the invention achieves the same advantages that were described above in connection with the method according to the invention and / or the measuring device according to the invention. These advantages are incorporated herein by reference in their entirety.

[0035] The invention further provides for the use of a measuring device, which can be designed as described above, for quality control of beverages, preferably carbonated beverages, in order to determine a pressure and / or carbon dioxide concentration of beverages, preferably carbonated beverages. In principle, however, quality control of all types of food is conceivable using the measuring device according to the invention.

[0036] Further measures improving the invention are presented in more detail below with the description of the preferred embodiments of the invention with reference to the figures. The features mentioned in the claims and in the description may be essential to the invention individually or in any combination. It should be noted that the figures are merely descriptive and are not intended to limit the invention in any way. They show: Fig. 1 a schematic setup for contactless characterization of a substance using waves in accordance with the invention, Fig. 2 spectral structures that can be determined using the setup according to Figure 1 were obtained, Fig. 3 an exemplary characteristic map for a spectral structure depending on a property of the substance, Fig. 4 a schematic setup for the contactless characterization of a substance using waves according to the prior art, Fig. 5 spectral structures obtained using the setup according to Figure 4 were obtained, Fig. 6 a spectral structure of the substance obtained according to the state of the art according to the Figures 4 and 5 was obtained, Fig. 7 a schematic setup for the contactless characterization of a substance using waves in accordance with the invention, Fig. 8 spectral structures obtained using the setup according to Figure 7 were obtained, Fig. 9 a spectral structure of the substance obtained by the invention according to the Figures 7 and 8was obtained, and Fig. 10 a schematic representation of a measuring device according to the invention in a possible application of the measuring device.

[0037] In the different figures, identical features of the invention are always provided with the same reference numerals, which is why they are generally described only once.

[0038] The Figure 1 shows a schematic setup for the contactless characterization of a substance A using waves W according to the invention in an ideal case. Using the schematic setup shown, comprising a transmitting element 13 and a receiving element 14, a spectral method is carried out. Using the spectral method, a spectral structure a( ẽ i ) of substance A, e.g. in the form of an absorption spectrum.

[0039] The Figures 1 and 2 For example, show three measurements x1, x2, x3 and correspondingly three spectral structures a( ẽ 1 ), a( ẽ 2 ), a( ẽ 3 ) for the measurements x1, x2, x3 as a function of a wavelength λ. The measurement x1 usually serves as a comparison measurement for the environment of substance A.

[0040] In the Figure 3 An example of a characteristic map KF is also shown. Figure 3 it is evident that the spectral structure a( ẽ i ) qualitatively depends on at least one property ei of substance A. To characterize substance A, an intersection between the measurements x1, x2, x3 and the characteristic field KF is sought. A spectral structure a( ẽ i ) from the characteristic map KF fits at least approximately to one of the measurements x1, x2, x3. This spectral structure a( ẽ i ) is selected as the measurement result. Based on this selected spectral structure a( ẽ i ) the property ei of substance A is also determined, such as the pressure e1 = P1, P2 or P3.

[0041] The Figures 1 to 3However, they show an ideal case. Normally, the substance, especially if it is gaseous or liquid, does not hang freely in space.

[0042] As the Figure 4 As the state of the art shows, a gaseous or liquid substance is usually held in a container B.

[0043] In known methods that use Figures 4, 5 and 6 As explained, reference or background spectra are usually recorded from container B (see measurement x2), in which substance A is later examined (see measurement x3). Here, too, a measurement x1 can serve as a reference measurement for the environment of substance A or for the source of the waves (W). The spectral structures a( ẽ 1 ), a( ẽ 2 ), a( ẽ 3 ) for the measurements x1, x2, x3 are in the Figure 5Known reference or background spectra of container B are filtered out from the actual spectrum of the substance using mathematical methods, as described in Figure 6 to remove the influence of container B when examining substance A as a known interfering structure s.

[0044] As the Figure 4 further suggests, measurements x2 and x3 are taken under the same measuring conditions, e.g. at the same position with respect to container B.

[0045] For many foods that are contained in sealed containers B, such as soft drinks, such procedures as those described in the Figures 4 to 6shown, however, is not applicable. The interference structures si are unknown in such investigations and cannot be determined without destroying the container B. The unknown interference structures si can result from unknown container geometry, interference phenomena, or the effects of extraneous phases in the measuring section between the transmitting element 13 and the receiving element 14.

[0046] The invention provides an improved method for the contactless or non-destructive characterization and / or examination of a substance A using waves W, in particular electromagnetic waves, which is based on the Figures 7 to 9 and 10The method according to the invention is intended to be particularly suitable for the quality control of foodstuffs, such as beverages G, preferably carbonated beverages G, which can be contained in sealed containers B. Furthermore, the method according to the invention can be used to determine the pressure P and / or a carbon dioxide concentration of the beverages G, preferably without destroying and / or opening the containers B (cf. Figure 10 ).

[0047] Substance A has a spectral structure a( ẽ i ) as a characteristic field KF, which depends qualitatively on at least one property ei of substance A, as shown above in the example of the Figure 3 is shown.

[0048] The spectral structure a( ẽ i ) of substance A is recorded by a measurement xj (cf. the Figures 7 and 8). The measurement xj may have an unknown interference structure sj, which depends on the measurement conditions. Under different measurement conditions, the interference structure sj may change quantitatively and / or qualitatively and the spectral structure a( ẽ i ) change quantitatively (e.g. by changing the optical path length): x 1 = g 1 ⋅ a + s 1 x 2 = g 2 ⋅ a + s 2 , where an exclusively quantitative change of the disturbance structure sj s j = h j ⋅ s not with an identically pronounced change in the spectral structure a( ẽ i ) (i.e. hj =gj ) in X.

[0049] Qualitative change means that: a e i ≠ e i ga const .

[0050] The invention provides that in step 1) at least two different measurements xj are carried out under different measuring conditions (cf. the Figures 7 and 8), which may have quantitatively and / or qualitatively different interference structures sj and / or quantitatively different spectral structures a(e;), and that in step 2) coefficients cj of a linear combination ∑ j = 1 M c j x j of the different measurements xj and the value ẽ i of at least one property of substance A must be optimized so that the deviation between the linear combination ∑ j = 1 M c j x j and the spectral structure a( ẽ i ) is minimized (see the Figure 9 ).

[0051] As it is in the Figure 7 using four measurements (M=4), in step 1) any number of measurements (preferably up to 80), but at least two different measurements xj are carried out under (deliberately) different measurement conditions. In accordance with the invention, with an increasing number M of measurements xj, the spectral structure a( ẽ i) of substance A must be distinguishable from the interfering structures sj in a Q-dimensional vector space.

[0052] To determine the spectral structure a( ẽ i ) of substance A, in step 2) a relevant subspace in the Q-dimensional vector space V can be found, in which the measurements xj mainly take place. The relevant subspace V x is at most the space spanned by the measurement vectors xj , j=1, ..., M themselves. The approach is now to determine the spectral structure a( ẽ i ) of the substance A in the relevant subspace V x using the characteristic field KF for the spectral structure a( ẽ i ) of substance A. This is done mathematically by determining the intersection between the spectral structure a( ẽ i ) of the substance A and this relevant subspace V x . For example, the intersection of the spectral structure a( ẽ i) of substance A can be determined using LS methods with the smallest distance to the relevant subspace V x. In this way, the spectral structure a( ẽ i ) of substance A can be recovered from the measured values. If the spectral structure a( ẽ i ) of substance A can be determined from the spectral structure a( ẽ i ) of substance A, the property ei of substance A to be determined can be deduced, such as the pressure P and / or the carbonic acid concentration of substance A, which can be present, for example, in the form of a carbonated beverage G.

[0053] In other words, in step 2) for optimizing, in particular indirectly, the coefficients cj of a linear combination cjxj of the measurements xj coefficients (ie ) of a linear combination ∑ h = 1 K d h u h of singular vectors uh, where the singular vectors uh are columns of a singular matrix U. U = u 11 … u K 1 … u M 1 … … … … … … … … … … u 1 Q … u KQ … u MQ , where the singular matrix U results from a singular value decomposition SVD (X = UΣV T< ) of a measurement data matrix X: X = x 11 … x M 1 … … … x 1 Q … x MQ and where the measurement data matrix X contains the measurements xj in the columns.

[0054] The method according to the invention can also be used to update the KF map.

[0055] As further stated by the Figure 10shows, the at least two different measurements xj from step 1) can be carried out in the region of a bottle head FK of a bottle F which contains a carbonated beverage G, wherein the substance A forms a content of the bottle head FK of the bottle F above the carbonated beverage F in the bottle F. A gas forms above the carbonated beverage G which, in the normal state in a sealed bottle F, is in thermodynamic equilibrium with the carbonated beverage G. If the gas has therefore been characterized as substance A, conclusions can be drawn about the pressure P and / or the carbonic acid concentration of the gas and thus of the carbonated beverage G.

[0056] The Figure 10further shows that a user can hold or move a measuring device 10 in the sense of the invention, similar to a barcode scanner, over the substance A, for example in the region of a bottle head FK when a carbonated beverage G is examined in a sealed container B. The measuring device 10 can be designed in the form of a laser measuring device, in particular a laser diode.

[0057] In contrast to known methods in which the measuring device must not be moved for a certain time, e.g. at least for 10 seconds, the measuring device 10 according to the invention can be handled more easily and conveniently.

[0058] Within the scope of the invention, it is conceivable that in step 1) a plurality of measurements xj are carried out over a period of up to 5 seconds, preferably 10 seconds, preferably 20 seconds.

[0059] The at least two different measurements xj can be carried out, for example, using electromagnetic waves, e.g. with a wavelength λ between 800 nm and 16 µm, in particular approximately 2400 nm.

[0060] The at least two different measurements xj can further be carried out using an optical method, in particular using a spectroscopic method, preferably an absorption spectroscopic method, preferably a rovibrational spectroscopic method.

[0061] The measuring device 10 can have a computer unit 11 which is designed to carry out the method according to the invention, in particular to carry out the optimizations in the sense of the method according to the invention in order to characterize the substance A.

[0062] Advantageously, the measuring device 10 may comprise a display unit 12 to display the characterized spectral structure a( ẽ i), whose deviation from the linear combination ∑ j = 1 M c j x j of the different measurements xj is minimized, and / or the determined value ẽ i to illustrate at least one property of substance A. The display unit 12 can also be used to display messages such as best before, expired, or the like.

[0063] Furthermore, a computer program product represents a further aspect of the invention. The computer program product can be stored in a memory 15 of the measuring device 10 and can carry out the method according to the invention when at least partially executed in the computer unit 11 of the measuring device 10.

[0064] The measuring device 10 according to the invention can advantageously be used for quality control of foodstuffs of any kind, such as beverages G, preferably carbonated beverages G, in order to determine a pressure P and / or a carbonic acid concentration of beverages G, preferably carbonated beverages G.

[0065] The above description of the figures describes the present invention solely by way of example. Of course, individual features of the embodiments can be freely combined with one another, provided this is technically feasible, without departing from the scope of the invention. The scope of the invention is defined by the claims. List of reference symbols

[0066] A Substance B Container F Bottle FK Bottle head G Beverage ei Properties of the substance e 1 Properties of the substance ẽ iValue of the property P Pressure P1 Pressure P2 Pressure P3 Pressure Pi Pressure N Number of properties KF Characteristic map x Measurement x 1 Measurement x 2 Measurement x 3 Measurement xj different measurements M Number of measurements a( ẽ i ) spectral structure g 1 · a spectral structure g 2 · a spectral structure gj · a quantitatively different spectral structures s noise structure s 1 noise structure s 2 noise structure sj quantitatively and / or qualitatively different noise structures cj coefficients ∑ j = 1 M c j x j Linear combination of the different measurements K Number of used singular vectors dh Coefficients uh Singular vectors ∑ h = 1 K d h u h Linear combination of singular vectors X Measurement data matrix Q Number of spectral channels SVD Singular value decomposition V Vector space V x Subspace W Waves λ Wavelength 10 Measuring device 11 Computer unit 12 Display unit 13 Transmitting element 14 Receiving element 15 Memory

Claims

1. Method for contactless characterization of a substance (A) using waves (W), wherein the substance (A) has a spectral structure (a(ẽi)) as a characteristic field (KF) which is qualitatively dependent on at least one property (ei) of the substance (A), wherein the spectral structure (a(ẽi)) is determined by at least two different measurements (xj), and wherein the at least two different measurements (xj) include disturbance structures (sj) which depend on the measurement circumstances, wherein in a step 1) the at least two different measurements (xj) are carried out under different measurement circumstances which have quantitatively and / or qualitatively different disturbance structures (sj) and possibly quantitatively different spectral structures (gj · a), and in a step 2) coefficients (cj) of a linear combination ( ∑ j = 1 M c j x j ) of the different measurements (xj) and the value (ẽi) of the at least one property (ei) of the substance (A) are optimized so that the deviation between the linear combination ( ∑ j = 1 M c j x j ) and the spectral structure (a(ẽi)) is minimized.

2. Method according to claim 1, characterized in that the at least two different measurements (xj) are carried out at different measuring angles and / or positions with respect to a container in which the substance (A) is located.

3. Method according to claim 1 or 2, characterized in that the at least two different measurements (xj) are carried out at different measurement angles and / or positions with respect to a bottle top (FK) of a bottle (F) which holds a carbonated beverage (G), the substance (A) forming a content of the bottle top (FK) of the bottle (F) above the carbonated beverage (G) in the bottle (F).

4. A method according to any one of the preceding claims, characterized in that in step 1) a plurality (M) of measurements (xj), preferably up to 80 measurements (xj), are carried out under different measurement conditions, and / or that in step 1) a plurality (M) of measurements (xj) are carried out over a period of up to 5 seconds, preferably 10 seconds, preferably 20 seconds.

5. A method according to any one of the preceding claims, characterized in that in step 1) the at least two different measurements (xj) are carried out using electromagnetic waves with a wavelength (λ) between 800 nm and 16 µm, in particular approx. 2400 nm, and / or that in step 1) the at least two different measurements (xj) are carried out using an optical method, in particular using a spectroscopic method, preferably an absorption spectroscopic method, preferably a rovibrational spectroscopic method.

6. A method according to any one of the preceding claims, characterized in that in step 1) the at least two different measurements (xj) are carried out with the aid of a laser measuring device, in particular a laser diode.

7. A method according to any one of the preceding claims, characterized in that in step 2) for optimizing, in particular indirectly, the coefficients (cj) of a linear combination (cjxj) of the measurements (xj) coefficients (dh) of a linear combination ( ∑ h = 1 K d h u h ) of singular vectors (uh) can be optimized, where the singular vectors (uh) are columns of a singular matrix (U), where the singular matrix (U) results from a singular value decomposition (SVD) of a measurement data matrix (X), and where the measurement data matrix (X) in the columns contains the measurements (xj) in the columns.

8. A method according to any one of the preceding claims, characterized in that in a step 3) by the spectral structure (a(ei)), whose deviation from the linear combination ( ∑ j = 1 M c j x j ) of the different measurements (xj0) is minimized, the value (ẽi) of at least one property (ei) of the substance (A) is determined, wherein in particular the value (ẽi) of the at least one property (ei) of the substance (A) forms a pressure and / or a carbonic acid concentration of a carbonated beverage (G).

9. A method according to any one of the preceding claims, characterized in that in a step 4), using the spectral structure (a(ẽi)) whose deviation from the linear combination ( ∑ j = 1 M c j x j ) of the various measurements (xj) is minimized, a characteristic field (KF) for the spectral structure (a(ẽi)) is updated.

10. Measuring device (10) for contactless characterization of a substance (A) using waves (W), characterized in that the measuring device (10) is designed to carry out a method according to one of the preceding claims.

11. Measuring device (10) according to the preceding claim, characterized in that the measuring device (10) has a computer unit (11) which is designed to calculate the coefficients (cj) of a linear combination ( ∑ j = 1 M c j x j ) of the various measurements (xj) and the value (ẽi) of the at least one property (ei) of the substance (A) in order to minimize the deviation between the linear combination ( ∑ j = 1 M c j x j ) and the spectral structure (a(ẽi )).

12. Measuring device (10) according to one of the preceding claims, characterized in that the measuring device (10) has a computer unit (11) which is designed to optimize, in particular indirectly, the coefficients (cj) of a linear combination (cjxj) of the measurements (xj) coefficients (dh) of a linear combination ( ∑ h = 1 K d h u h ) of singular vectors (uh) can be optimized, where the singular vectors (uh) are columns of a singular matrix (U), where the singular matrix (U) results from a singular value decomposition (SVD) of a measurement data matrix (X), and where the measurement data matrix (X) in the columns contains the measurements (xj) in the columns.

13. Measuring device (10) according to one of the preceding claims, characterized in that the measuring device (10) has a display unit (12) which is designed to display the spectral structure (a(ẽi)), the deviation of which from the linear combination ( ∑ j = 1 M c j x j ) of the various measurements (xj) is minimized, and / or the determined value (ẽi) of the at least one property (ei) of the substance (A).

14. Computer program product which can be stored in a memory (15) of a measuring device (10) according to one of the preceding claims 10 to 13, and which, when at least partially executed in a computer unit (11) of the measuring device (10), performs a method according to one of the preceding claims 1 to 9.

15. Use of a measuring device (10) according to one of the preceding claims 10 to 13 for quality control of beverages (G), preferably carbonated beverages (G), in order to determine a pressure (p) and / or a carbon dioxide concentration of beverages (G), preferably carbonated beverages (G).