DE102016226241A1 - Interferometer component, method for producing an interferometer component and method for operating an interferometer component - Google Patents

Abstract

The invention relates to an interferometer component (100) having an optical resonator (102) comprising at least a first mirror element (104) and a second mirror element (106) arranged opposite the first mirror element (104). The first mirror element (104) and the second mirror element (106) are segmented into at least a first transmission segment (108) and a second transmission segment (110) for transmitting light through the optical resonator (102). In this case, the first mirror element (104) and the second mirror element (106) in the first passage segment (108) at a different distance from one another than in the second passage segment (110).

Description

State of the art

The invention is based on a device or a method according to the preamble of the independent claims. The subject of the present invention is also a computer program.

The DE 10 018 444 A1 describes a semiconductor system for recording spectra, color signals, color images and the like, consisting of a CCD or CMOS chip with a plurality of photosensitive pixels, each with a preceding color filter.

Disclosure of the invention

Conventional micromechanical Fabry-Perot interferometers are inherently limited in their functional range due to the occurrence of higher orders in their usable wavelength range towards low wavelengths. For analytical questions, however, operation over the widest possible wavelength range is desirable. Unwanted orders can be filtered out of the spectrum, for example, by additional optical elements.

Against this background, with the approach presented here, an interferometer component, a method for producing an interferometer component, a method for operating an interferometer component, furthermore a device which uses at least one of these methods, and finally a corresponding computer program according to the main claims are presented. The measures listed in the dependent claims advantageous refinements and improvements of the independent claim device are possible.

• einem optischen Resonator umfassend zumindest ein erstes Spiegelelement und ein gegenüber dem ersten Spiegelelement angeordnetes zweites Spiegelelement, wobei das erste Spiegelelement und das zweite Spiegelelement in zumindest ein erstes Durchlasssegment und ein zweites Durchlasssegment zum Durchlassen von Licht durch den optischen Resonator segmentiert sind, wobei das erste Spiegelelement und das zweite Spiegelelement im ersten Durchlasssegment einen anderen Abstand zueinander aufweisen als im zweiten Durchlasssegment.

An interferometer component with the following feature is presented:

• an optical resonator comprising at least a first mirror element and a second mirror element arranged opposite the first mirror element, wherein the first mirror element and the second mirror element are segmented into at least a first passage segment and a second passage segment for transmitting light through the optical resonator, wherein the first mirror element and the second mirror element in the first passage segment have a different distance from one another than in the second passage segment.

By an optical resonator, for example, a Fabry-Perot resonator can be understood. Under a mirror element can be understood as a partially transparent mirror layer or plate. The two mirror elements may in this case be arranged, for example, parallel to one another at a specific distance. The distance can be varied by means of a suitable Spiegelaktuierung. A passage segment may be understood to mean a section of the optical resonator which extends transversely to a light incidence direction and has a specific gap spacing. The segmentation into the two passage segments can be realized, for example, in that the two mirror elements are offset in height parallel to one another in the region of the passage segments.

The approach presented here is based on the finding that a tunable micromechanical Fabry-Perot interferometer with extended useful wavelength range can be realized by segmenting the two mirror elements of an optical resonator into segments with different distances between the mirror elements and thus different resonator lengths. In particular, the extension of the usable wavelength range is made possible by measuring partly adjacent spectral ranges in the different transmission segments.

In one embodiment, the interferometer device may include a detector unit for detecting light. The detector unit may be segmented into at least one first detector segment for providing a first measurement signal and a second detector segment for providing a second measurement signal. In this case, the detector unit and the optical resonator can be combined with one another in such a way that the first detector segment and the first passage segment lie opposite one another and the second detector segment and the second passage segment lie opposite one another. A detector unit may be understood to mean a light sensor, for example in the form of a CCD or CMOS sensor, a photodiode or a phototransistor. This allows a separate measurement of the transmitted through the two passage segments spectra.

Furthermore, the interferometer device may comprise a substrate layer having at least a first light transmission zone and a second light transmission zone for transmitting light through the substrate layer. The substrate layer and the optical resonator may be combined with each other such that the first light transmission zone and the first transmission segment face each other and the second light transmission zone and the second transmission segment face each other. A substrate layer may be understood as meaning a layer of a transparent material, depending on the embodiment may be covered in sections with an opaque layer. A light transmission zone may be understood to mean a light-transmitting section of the substrate layer. By means of this embodiment, light emerging from the optical resonator can be controlled and directed with the least possible loss of intensity in a specific direction, in particular on the detector unit.

According to a further embodiment, the detector unit, the substrate layer and the optical resonator can be combined with one another such that the first light transmission zone lies between the first passage segment and the first detector segment and the second light transmission zone lies between the second transmission segment and the second detector segment. As a result, the interferometer component can be realized as compactly as possible and with the shortest possible optical paths.

It is advantageous if the first light transmission zone or the second light transmission zone is formed by a cavern in the substrate layer or both light transmission zones are formed by a cavern in the substrate layer. Additionally or alternatively, the two light transmission zones may be transmissive for different wavelengths. As a result, the light transmission zones can be realized with the least possible manufacturing effort. Furthermore, this can improve the measurement accuracy of the interferometer device.

According to a further embodiment, the first mirror element may have a bulge in the first passage segment or in the second passage segment or in both passage segments. Additionally or alternatively, the second mirror element may also have a bulge in the first passage segment or in the second passage segment or in both passage segments. By this embodiment, the segmentation of the optical resonator can be realized particularly easily.

In addition, the interferometer component may have at least one adhesion-reducing element for preventing adhesion of the first mirror element to the second mirror element. In this case, the adhesion-reducing element can be arranged in a transition region between the first passage segment and the second passage segment between the first mirror element and the second mirror element. An adhesion-reducing element may be understood to mean a component made of an adhesion-reducing material, for example a so-called anti-stiction stop bump. The adhesion-reducing element may be attached either to the first mirror element, to the second mirror element or to both mirror elements. By this embodiment, adhesion of the first mirror element to the second mirror element can be prevented.

It is also advantageous if the first mirror element and the second mirror element are segmented into at least one third passage segment for the passage of light through the optical resonator. In this case, the first mirror element and the second mirror element in the third passage segment may have the same distance from each other as in the first passage segment. Alternatively, the first mirror element and the second mirror element in the third passage segment may have a greater distance from one another than in the first passage segment or in the second passage segment. As a result, the usable wavelength range of the interferometer component can be additionally expanded.

It is advantageous if the second passage segment is arranged between the first passage segment and the third passage segment. This allows efficient operation of the interferometer device.

• Bilden eines optischen Resonators aus zumindest einem ersten Spiegelelement und einem zweiten Spiegelelement, wobei das erste Spiegelelement und das zweite Spiegelelement einander gegenüberliegend angeordnet werden und derart in zumindest ein erstes Durchlasssegment und ein zweites Durchlasssegment zum Durchlassen von Licht durch den optischen Resonator segmentiert werden, dass das erste Spiegelelement und das zweite Spiegelelement im ersten Durchlasssegment einen anderen Abstand zueinander aufweisen als im zweiten Durchlasssegment.

The approach presented here also provides a method for producing an interferometer component, the method comprising the following step:

• Forming an optical resonator comprising at least a first mirror element and a second mirror element, wherein the first mirror element and the second mirror element are arranged opposite one another and are segmented into at least a first transmission segment and a second transmission segment for transmitting light through the optical resonator first mirror element and the second mirror element in the first passage segment have a different distance from one another than in the second passage segment.

• Einlesen des ersten Messsignals und des zweiten Messsignals; und
• Ermitteln eines Transmissionsspektrums des Interferometerbauelements unter Verwendung des ersten Messsignals und des zweiten Messsignals.

Finally, the approach presented here provides a method for operating an interferometer component according to one of the preceding embodiments, wherein the method comprises the following steps:

• Reading the first measuring signal and the second measuring signal; and
• Determining a transmission spectrum of the interferometer device using the first measurement signal and the second measurement signal.

These methods can be used, for example, in software or hardware or in a hybrid form from software and hardware, for example in a control unit, be implemented.

The approach presented here also creates a device that is designed to perform the steps of a variant of a method presented here in appropriate facilities to drive or implement. Also by this embodiment of the invention in the form of a device, the object underlying the invention can be solved quickly and efficiently.

For this purpose, the device may comprise at least one computing unit for processing signals or data, at least one memory unit for storing signals or data, at least one interface to a sensor or an actuator for reading sensor signals from the sensor or for outputting data or control signals to the sensor Actuator and / or at least one communication interface for reading or outputting data embedded in a communication protocol. The arithmetic unit may be, for example, a signal processor, a microcontroller or the like, wherein the memory unit may be a flash memory, an EPROM or a magnetic memory unit. The communication interface can be designed to read or output data wirelessly and / or by line, wherein a communication interface that can read or output line-bound data, for example, electrically or optically read this data from a corresponding data transmission line or output in a corresponding data transmission line.

In the present case, a device can be understood as meaning an electrical device which processes sensor signals and outputs control and / or data signals in dependence thereon. The device may have an interface, which may be formed in hardware and / or software. In the case of a hardware-based embodiment, the interfaces can be part of a so-called system ASIC, for example, which contains a wide variety of functions of the device. However, it is also possible that the interfaces are their own integrated circuits or at least partially consist of discrete components. In a software training, the interfaces may be software modules that are present, for example, on a microcontroller in addition to other software modules.

Also of advantage is a computer program product or computer program with program code which can be stored on a machine-readable carrier or storage medium such as a semiconductor memory, a hard disk memory or an optical memory and for carrying out, implementing and / or controlling the steps of the method according to one of the embodiments described above is used, especially when the program product or program is executed on a computer or a device.

• 1 eine schematische Darstellung eines Interferometerbauelements gemäß einem Ausführungsbeispiel;
• 2 eine schematische Darstellung eines Interferometerbauelements gemäß einem Ausführungsbeispiel;
• 3 ein Diagramm zur Darstellung einer normalisierten Transmission in einem Fabry-Perot-Interferometer in Abhängigkeit von einer Wellenlänge;
• 4 ein Ablaufdiagramm eines Verfahrens zum Herstellen eines Interferometerbauelements gemäß einem Ausführungsbeispiel; und
• 5 ein Ablaufdiagramm eines Verfahrens zum Betreiben eines Interferometerbauelements gemäß einem Ausführungsbeispiel.

Embodiments of the invention are illustrated in the drawings and explained in more detail in the following description. It shows:

• 1 a schematic representation of an interferometer according to an embodiment;
• 2 a schematic representation of an interferometer according to an embodiment;
• 3 a diagram showing a normalized transmission in a Fabry-Perot interferometer as a function of a wavelength;
• 4 a flowchart of a method for producing an interferometer device according to an embodiment; and
• 5 a flowchart of a method for operating an interferometer device according to an embodiment.

In the following description of favorable embodiments of the present invention, the same or similar reference numerals are used for the elements shown in the various figures and similar acting, with a repeated description of these elements is omitted.

1 shows a schematic representation of an interferometer device 100 according to an embodiment. Shown is a cross section through an embodiment of the interferometer device 100 with passage areas with a total of two different gap heights. The interferometer device 100 comprises an optical resonator 102 Here, for example, a Fabry-Perot resonator, hereinafter also referred to as a short resonator, which is a first mirror element 104 and one opposite to the first mirror element 104 at a certain distance arranged second mirror element 106 includes. The two mirror elements 104 . 106 , in 1 exemplified realized as mirror layers, are in a first passage segment 108 and a second passage segment 110 for passing light through the resonator 102 segmented. The two passage segments 108 . 110 differ in that the mirror elements 104 . 106 in the passage segments 108 . 110 each have a different gap distance from each other. Exemplary are the mirror elements 104 . 106 in the first passage segment 108 at a smaller distance arranged to one another as in the second passage segment 110 ,

According to the in 1 In the embodiment shown, the segment-dependent variation of the gap spacing is achieved in that the first mirror element 104 in the region of the second passage segment 110 a bulge 112 through which the mirror elements 104 . 106 are offset in height parallel to each other. Depending on the embodiment, additionally or alternatively, the second mirror element 106 a corresponding recess or indentation in at least one of the two passage segments 108 . 110 exhibit.

As in 1 shown by way of example is the second mirror element 106 via a spring perforation 114 along an optical axis 116 the interferometer component 100 movable on the first mirror element 104 arranged. A distance between the two mirror elements 104 . 106 is for example by means of two control electrodes 118 controllable Spiegelaktuierung variable.

According to this embodiment, the optical resonator 102 with a substrate layer 120 from a translucent material to a Fabry-Perot interferometer filter device 122 combined. Here is the first mirror element 104 on a surface of the substrate layer 120 applied. The substrate layer 120 has a first light transmission zone opposite to the first transmission segment 108 124 and one opposite to the second passage segment 110 arranged second light transmission zone 126 for passing through the optical resonator 102 in the substrate layer 120 falling light. Exemplary are the two light transmission zones 124 . 126 each through a continuous cavity in the substrate layer 120 formed, whose wall surfaces in addition a mirroring 128 exhibit.

Furthermore, the interferometer component comprises 100 a detector unit 130, also called detector component, analogous to the optical resonator 102 in a first detector segment 132 and a second detector segment 134 is segmented. The detector unit 130 is so with the substrate layer 120 combined that the first detector segment 132 the first light transmission zone 124 and the second detector segment 134 the second light transmission zone 126 opposite. The substrate layer 120 is thus between the optical resonator 102 and the detector unit 130 arranged, with the optical axis 116 at the same time an optical axis of the detector unit 130 represents. The first detector segment 132 is configured to an intensity of the through the first light transmission zone 124 to measure falling light and a corresponding first measurement signal 136 provide. In a corresponding manner, the second detector segment 134 formed to an intensity of the through the second light transmission zone 126 to measure falling light and a corresponding second measurement signal 138 provide. To the detector unit 130 is a device 140 connected, which is a reading unit 142 for reading the two measuring signals 136 . 138 For example, a control unit 143 for adjusting the resonator gap and an evaluation unit 144 for detecting and evaluating the two measuring signals 136 . 138 as a function of the resonator gap.

As a result of the evaluation, the evaluation unit provides 144 an evaluation signal 146 which provides a transmission spectrum of the interferometer component 100 represents.

Optionally, the detector unit 130 in addition to the two detector segments 132 . 134 one outside the two light transmission zones 124 126 reference segment 148 for a dark measurement using the device 140 on.

According to the in 1 In the embodiment shown, the optical resonator 102 is additionally in a third passage segment 150 segmented, in which the two mirror elements 104 . 106 exemplarily have the same distance from each other as in the first passage segment 108 , Here is the second passage segment 110 between the first passage segment 108 and the third passage segment 150 arranged. Depending on the embodiment, the optical resonator 102 also have more than three passage segments. The passage segments 108 . 110 . 150 are each separated by a transition region 152, the in 1 by way of example by two recess flanks in the first mirror element 104 is indicated. It is in the transition area 152 between the two mirror elements 104 . 106 one optional liability reduction element 154 , here's an anti-stiction stop bump, arranged in that 1 by way of example on the second mirror element 106 is appropriate. The surfaces of the substrate layer 120 can in the transition area 152 mirrored or coated with an absorbent material.

According to the segmentation of the optical resonator 102 is the substrate layer 120 with a third light transmission zone 156 , here likewise in the form of a continuous cavern, realized opposite to the third passage segment 150 is arranged to light incident through the third passage segment 150 to a light transmission zone opposite to the third 156 arranged third detector segment 158 the detector unit 130 to steer. Analogous to the two detector segments 132 . 134 is the third detector segment 158 trained to a third measuring signal 160 provide a spectral intensity of that of the third light transmission zone 156 transmitted light, wherein the device 140 the transmission spectrum of the interferometer component 100 with the additional use of the third measurement signal 160 determined.

2 shows a schematic representation of an interferometer device 100 according to an embodiment. The interferometer component 100 essentially corresponds to the above with reference to 1 described interferometer device, with the difference that the substrate layer 120 in the first light transmission zone 124 has no cavern. Instead, the long wavelength portion of the light passes through the first passage segment 108 incident light through the translucent material of the substrate layer 120 Transmitted, for example, is realized as a silicon substrate, while the short-wave component of the light is absorbed. Thus, the first light transmission zone 124 functions as an edge filter for the first transmission segment 108 ,

Hereinafter, various embodiments of the approach presented here will be described again in other words.

The interferometer component 100 is, for example, as a micromechanical, integrated spectrometer system consisting of a detector unit 130 and an actuatable Fabry-Perot interferometer device, also known as an optical resonator 102 called, realized with a common optical axis. Both have a common segmentation in different areas. The optical resonator 102 has at least two mirror elements 104 . 106 with at least two passage segments 108 . 110 on, which are characterized in that the gap distance between the mirror elements 104 . 106 varies from passage segment to passage segment. At least one of the two mirror elements has a comparison with a remaining mirror surface parallel height offset passage segment. The substrate layer 120 points, for example, in the transition areas 152 between and / or in the passage segments for at least part of a wavelength range impermeable areas. The opacity of the substrate walls is achieved, for example, by mirroring or absorption layers, for example in the form of a metal coating. The substrate layer 120 may function as a longpass filter under a portion of the passage segments.

Optionally, at least one of the mirror elements is in the transition region 152 Anti-Stiction Stop Bumps as Liability Reduction Elements 154 on.

The detector unit 130 has the same segmentation and segmentation arrangement as the filter device 122 on. The individual detector segments can be read out separately. Here, the detector unit 130 mounted in the same optical axis so that maximum overlap of the segmentations arise. In this way, the transmission segments with their spectral transmission characteristic can be uniquely assigned to a detector segment.

In Fabry-Perot interferometers, the resonance condition for maximum transmission (in the simplest case, the gap spacing corresponds to an integer multiple of half the wavelength) is satisfied by higher orders in addition to the fundamental wavelength. The result of this is that a spectrally usable region of a Fabry-Perot interferometer is limited to short wavelengths in each case by the next higher mode or, in the absence of a long-pass filter, the spectra are superposed with the spectra of higher orders, as described in US Pat 3 is shown.

For analytics, especially about food analysis, on the other hand, the broadest usable spectrum is usually desirable. The larger and higher resolution the spectrally measured area is, the better the measurements can be correctly classified or quantified and the more applications can be covered.

The approach presented here now makes it possible for different wavelengths in the various passage segments to be resonant at the same time and thus transmitted. In particular, however, the same orders do not occur over the tunable range. For a known gap height difference, therefore, the resonance wavelengths can be related to each other. By subtracting the intensity measurement curves of the various transmission segments, this procedure allows the original spectrum to be reconstructed over a larger spectral range than would be possible with a single gap height.

The different mirror spacings are achieved, for example, by pre-structuring the substrate layer 120 and a subsequent deposition of the mirror layers 104 . 106 realized.

As already mentioned, the substrate layer 102 for example in the transition areas 152 have impermeable regions between and / or in the passage segments for at least part of the spectral region. In this way, it is also possible by subtraction of the intensity curves of the different passbands the original spectrum over to clearly reconstruct a larger spectral range.

Through the mirroring 128 it is avoided that filtered oblique partial beams leave the window of a certain passage segment and on the detector unit 130 be absorbed in a neighboring detector segment, whereby the signal would be corrupted.

At least one of the mirror elements has, in particular in the transition region 152 , an adhesion-reducing element 154 on. The transition area 152 between the passage segments can not be used optically, because he has no defined gap distance. Logically, the transition area 152 but for the liability reduction element 154 be used, which in turn would rather disturb the passage segments.

According to a further embodiment, the detector segments are realized from different detector materials. Bandpass or edge filters are optionally applied to the individual detector segments.

In order to avoid crosstalk from one passage segment to an adjacent, unrelated detector segment, the filter device 122 may be applied such that the substrate layer 120 points upwards. So the vertical distance between the detector unit 130 and the filter device 122 and thus reduces the crosstalk. The application can by flip-chip by the construction and connection technology or by a wafer bond of a filter component 122 having a filter wafer on a detector unit 130 having detector wafer can be realized.

Alternatively, the detector segments are monolithically integrated on the substrate side of the filter wafer.

3 shows a diagram 300 for representing a normalized transmission in a Fabry-Perot interferometer as a function of a wavelength.

4 shows a flowchart of a method 400 for producing an interferometer component according to an exemplary embodiment, for example a preceding one with reference to FIG 1 and 2 described interferometer device. It is in one step 410 an optical resonator is formed from at least a first mirror element and a second mirror element. The two mirror elements are in the step 410 arranged opposite each other and so segmented into at least a first passage segment and a second passage segment for transmitting light through the optical resonator that the first mirror element and the second mirror element in the first passage segment have a different distance from each other than in the second passage segment.

5 shows a flowchart of a method 500 for operating an interferometer component according to an exemplary embodiment. The method 500 may be implemented, for example, using a device as described above with reference to FIG 1 is described. It will be in one step 510 the two measuring signals are read. In a step 520, the evaluation of the two measurement signals takes place in order to determine the transmission spectrum of the interferometer component.

If an exemplary embodiment comprises a "and / or" link between a first feature and a second feature, then this is to be read so that the embodiment according to one embodiment, both the first feature and the second feature and according to another embodiment either only first feature or only the second feature.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 10018444 A1 [0002]

Claims (14)

Interferometer component (100) with the following feature: an optical resonator (102) comprising at least a first mirror element (104) and a second mirror element (106) arranged opposite the first mirror element (104), wherein the first mirror element (104) and the second mirror element (106) are segmented into at least a first transmission segment (108) and a second transmission segment (110) for transmitting light through the optical resonator (102), the first mirror element (104). and the second mirror element (106) in the first passage segment (108) have a different distance from one another than in the second passage segment (110). Interferometer component (100) according to Claim 1 , with a detector unit (130) for detecting light, wherein the detector unit (130) segments into at least a first detector segment (132) for providing a first measurement signal (136) and a second detector segment (134) for providing a second measurement signal (138) wherein the detector unit (130) and the optical resonator (102) are combined with each other such that the first detector segment (132) and the first passage segment (108) face each other and the second detector segment (134) and the second transmission segment (110) opposite each other. An interferometer device (100) according to any one of the preceding claims, comprising a substrate layer (120) having at least a first light transmission zone (124) and a second light transmission zone (126) for transmitting light through the substrate layer (120), the substrate layer (120) and optical resonators (102) are combined with each other such that the first light transmission zone (124) and the first transmission segment (108) oppose each other and the second light transmission zone (126) and the second transmission segment (110) face each other. Interferometer component (100) according to Claim 2 and 3 in which the detector unit (130), the substrate layer (120) and the optical resonator (102) are combined such that the first light transmission zone (124) lies between the first passage segment (108) and the first detector segment (132) and the second light transmission zone (126) between the second passage segment (110) and the second detector segment (134). Interferometer component (100) according to Claim 3 or 4 in which the first light transmission zone (124) and / or the second light transmission zone (126) is formed by a cavern in the substrate layer (120) and / or in which the first light transmission zone (124) and the second light transmission zone (126) for different wavelengths are permeable. Interferometerbauelement (100) according to one of the preceding claims, wherein the first mirror element (104) and / or the second mirror element (106) in the first passage segment (108) and / or in the second passage segment (110) has a bulge (112). Interferometer component (100) according to one of the preceding claims, having at least one adhesion-reducing element (154) for preventing adhesion of the first mirror element (104) to the second mirror element (106), wherein the adhesion-reducing element (154) in a transition region (152) between the first Passage segment (108) and the second passage segment (110) between the first mirror element (104) and the second mirror element (106) is arranged. The interferometric device (100) of any of the preceding claims, wherein the first mirror element (104) and the second mirror element (106) are segmented into at least a third transmission segment (150) for transmitting light through the optical resonator (102), the first one Mirror element (104) and the second mirror element (106) in the third passage segment (150) have the same distance from each other as in the first passage segment (108). Interferometer component (100) according to Claim 8 in that the second passage segment (110) is disposed between the first passage segment (108) and the third passage segment (150). A method (400) of making an interferometer device (100), the method (400) comprising the step of: Forming (410) an optical resonator (102) comprising at least a first mirror element (104) and a second mirror element (106), wherein the first mirror element (104) and the second mirror element (106) are arranged opposite to each other and segmented into at least a first transmission segment (108) and a second transmission segment (110) for transmitting light through the optical resonator (102) the first mirror element (104) and the second mirror element (106) have a different distance from each other in the first passage segment (108) than in the second passage segment (110). A method (500) of operating an interferometer device (100) according to any one of Claims 2 to 9 wherein the method (500) comprises the steps of: reading (510) the first measurement signal (136) and the second measurement signal (138); and determining (520) a transmission spectrum of the interferometer device (100) using the first measurement signal (136) and the second measurement signal (138). Apparatus (140) comprising units (142, 144) adapted to perform the method (400) in accordance with Claim 10 and / or the method (500) according to Claim 11 execute and / or control and / or implement. A computer program configured to execute the method (400) Claim 10 and / or the method (500) according to Claim 11 execute and / or control and / or implement. Machine-readable storage medium on which the computer program is based Claim 13 is stored.

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