WO2024180167A1

WO2024180167A1 - Sensor arrangement and method of operating a sensor arrangement

Info

Publication number: WO2024180167A1
Application number: PCT/EP2024/055174
Authority: WO
Inventors: Alexander Gaiduk; Stefano Guerrieri
Original assignee: Ams-Osram Ag
Priority date: 2023-03-02
Filing date: 2024-02-29
Publication date: 2024-09-06

Abstract

A sensor arrangement (1) comprising a detector array (2) and a functional module (3) comprising a plurality of functional areas (31, 32) is specified, wherein - at least one of the functional areas (31, 32) overlaps with the detector array when seen in a vertical direction onto the detector array; - the functional areas (31, 32) are arranged side-by-side when seen in the vertical direction; and - the sensor arrangement (1) is configured to perform a spectral calculation of a radiation impinging onto a first functional area (31) of the plurality of functional areas (31, 32). A method of operating a sensor arrangement (1) is further specified.

Description

SENSOR ARRANGEMENT AND METHOD OF OPERATING A SENSOR ARRANGEMENT

The present application refers to a sensor arrangement and to a method of operating a sensor arrangement .

Hyperspectral and multispectral imaging are used for a number of tasks in fields of industry, medicine or healthcare , for instance . Typically, the spatial resolution, the spectral resolution, the noise and the signal-to-noise ratio as well as the integration time are strongly interconnected for hyperspectral and multispectral imaging . For applications where compactness and relatively low costs are required, low spectral resolution multispectral imaging with relatively low spatial resolution is not suf ficient to provide satis factory results .

An obj ect to be solved is to provide reliable sensing with a compact device .

This obj ect is solved inter alia by a sensor arrangement with the features of claim 1 . The further claims refer to further aspects and expediencies .

A sensor arrangement comprising a detector array is speci fied . The detector array in particular comprises a plurality of detector pixels configured to detect electromagnetic radiation, for example in the visible , ultraviolet or infrared spectral range . According to at least one embodiment of the sensor arrangement , the sensor arrangement comprises a functional module comprising a plurality of functional areas . For example , the functional areas di f fer from one another with respect to the radiation transmitted through the respective functional area and impinging onto detector pixels underneath the respective functional area, for example with respect to an optical property such as spectral transmission, polari zation or beam shaping .

According to at least one embodiment of the sensor arrangement , at least one of the functional areas overlaps with the detector array when seen in a vertical direction onto the detector array . The functional areas are arranged side-by-side when seen in the vertical direction . The functional areas taken together may cover the detector array completely or at least in part . Further, the functional module may extend laterally beyond the detector array .

In the context of the present application, a lateral direction is a direction that extends perpendicular with respect to the vertical direction .

According to at least one embodiment of the sensor arrangement , the sensor arrangement is configured to perform a spectral calculation of a radiation impinging onto a first functional area of the plurality of functional areas . For example , the first functional area serves for a determination of a spectrum of the radiation without any spatial resolution . For example , during the detection of the radiation, the first functional area covers a plurality of detector pixels . In at least one embodiment , a sensor arrangement comprises a detector array and a functional module comprising a plurality of functional areas wherein at least one of the functional areas overlaps with the detector array when seen in a vertical direction onto the detector array and the functional areas are arranged side-by-side when seen in the vertical direction . The sensor arrangement is configured to perform a spectral calculation of radiation impinging onto a first functional area of the plurality of functional areas .

In the sensor arrangement , the first functional area may be used to determine the spectrum of the impinging radiation . One or more further functional areas may be used to obtain further information with spatial resolution, for instance . Thus , the sensor arrangement may provide both data with spatial information and a spectrum of the impinging radiation, in particular simultaneously . By combining this information a highly precise analysis of radiation from a scene or obj ect may be performed .

According to at least one embodiment of the sensor arrangement , the first functional area comprises an interferometer array with a plurality of interferometers arranged side-by-side when seen in the vertical direction . In other words , the interferometer array represents a functional element extending over the first functional area . For example , the interferometers are arranged in a onedimensional array . For example , the interferometers di f fer from one another with respect to a path di f ference for the radiation to be detected . Due to the plurality of interferometers it is not necessary to provide any moving parts in order to obtain an interferogram . For example , the interferometer array is formed using a crystal which is transmissive for the radiation to be detected . By means of the interferometer array, the spectrum of the radiation may be obtained with a high resolution . For example , at a wavelength of 400 nm a spectral resolution of 1 nm can be obtained by 400 interferometers with fixed di f ferences in path length varying from 0 to 400* 400nm=0 . 16mm . At least two detector pixels of the detector array are assigned to each interferometer, for instance in order to obtain suf ficient sampling of the interferogram .

According to at least one embodiment of the sensor arrangement , the sensor arrangement is configured to calculate a spectrum of the radiation based on a Fourier Trans form calculation of a signal of detector pixels of the detector array that are assigned to the first functional area . For example , at least along one direction at least 150 detector pixels or at least 300 detector pixels or at least 500 detector pixels are assigned to the first functional area . It has been found that the spectral resolution increases with the number of interferometers and associated detector pixels . For example , the interferometers are arranged along a row of the detector array wherein the number of detector pixels within the first functional area in this row is at least as large as the number of interferometers , preferably at least by a factor of 2 larger than the number of interferometers .

Further rows of the detector array may be used to measure a signal from the same interferometer array, so that each of the rows provides an interferogram from which the spectrum of the radiation can be obtained . By averaging the spectra obtained from individual rows a final spectrum with reduced noise results . In this context the terms "row" and "column" of the detector array are interchangeable and merely refer to two di f ferent directions perpendicular to one another .

According to at least one embodiment of the sensor arrangement , at least one second functional area of the plurality of functional areas is configured for spectral or multispectral imaging . Thus , radiation within associated spectral range ( s ) is detected in a spatially resolved manner by the at least one second functional area .

According to at least one embodiment of the sensor arrangement , at least three or at least five of the second functional areas mutually di f fer from another with respect to a wavelength of maximum sensitivity . For example , the wavelengths of maximum sensitivity di f fer from one another by at least 10 nm or 20 nm or 50 nm . The wavelength of maximum sensitivity may be located in the visible , the infrared or the ultraviolet spectral range .

According to at least one embodiment of the sensor arrangement , at least one second functional area comprises a tunable interference filter . Thus , during operation of the sensor arrangement , the wavelength of maximum sensitivity may be tuned . Consequently, the same functional area may be used to sequentially obtain a spatially resolved image at di f ferent wavelengths of maximum sensitivity .

According to at least one embodiment of the sensor arrangement , the second functional areas in each case the second functional areas in each case are assigned to at least 15 detector pixels or at least 50 or at least 100 pixels along one direction of the detector array . An improved spatial resolution may be obtained an increased number of detector pixels assigned to the respective second functional area during the detection .

According to at least one embodiment of the sensor arrangement , at least one of the functional areas is configured for direct imaging, time resolved detection, polari zation sensing, stereo imaging or light emission . Thus , one , two or more of these functions may be provided by the sensor arrangement using the same detector array .

According to at least one embodiment of the sensor arrangement , the functional module is movable with respect to the detector array . For example , the functional module can be moved by the user in order to switch between two or more operation modes of the sensor arrangement . In this case the functional module typically has a larger lateral extent than the detector array, at least with respect to one lateral direction . For example , the optically usable area of the functional module is by a factor of 2 or a factor of 3 larger than the optically usable area of the detector array .

According to at least one embodiment of the sensor arrangement , all detector pixels of the detector array are formed in a single semiconductor chip . For example , the detector pixels comprise silicon .

However, the detector array may have di f ferent areas that are technologically di f ferent from one another and placed on the same single chip . For example , di f ferent areas may deliver di f ferent light spectral sensitivity while having the same or a similar pixel si ze and/or pixel configuration . For example , the detector array may comprise a backside illuminated and/or frontside illuminated image sensing area based on CMOS technology . The spectral sensitivity may be adapted for at least some detector pixels or all detector pixels using a cover layer from a material with a sensitivity in the shortwave infrared or mid-infrared spectral range . For example , the cover layer may comprise quantum dots , I I I-V compound semiconductor materials and/or germanium-on-silicon .

Using di f ferent si zes , the functional areas may be better adapted to their speci fic requirements . Further, also the shape of the functional areas may vary .

According to at least one embodiment of the sensor arrangement , the sensor arrangement is configured for a mobile or wearable device . For example , a footprint of the sensor arrangement is at most 2 cm² or 1 cm² or 0 . 5 cm² . A height of the sensor arrangement is , for example , at most 2 cm or at most 1 cm or at most 7 mm .

Further, a method of operating the sensor arrangement is speci fied . According to at least one embodiment of the method, the method comprises the step of acquiring a spectrum using the first functional area and the step of acquiring at least one image using at least one second functional area of the functional module , in particular based on the spectrum .

Using the information from the first functional area and from the at least one second functional area allows spatial information and highly precise spectral information on the image to be obtained at the same time . According to at least one embodiment of the method, the at least one second functional area used for acquisition is selected based on its spectral sensitivity . In other words , the spectrum obtained from the first functional area may be used to determine which ones of the second functional areas should be used and further processed .

For example , the obtained spectrum is used to identi fy spectral channels of the sensor arrangement that are particularly suited to provide reliable information for the speci fic application needs .

For example , the sensor arrangement and/or the method may be used to identi fy di f ferent light sources in ambient light or to monitor health or physiological conditions or for human skin identi fication or face identi fication .

Features described above in connection with at least one embodiment of the sensor arrangement or the method can be combined with other features described in connection with at least one embodiment of the sensor arrangement or the method, unless they are contradictory .

Further aspects and expediencies will be apparent from the subsequent description of the exemplary embodiments in connection with the figures .

In the figures :

Figure 1A shows an embodiment of a detector array of a sensor arrangement wherein Figures IB, 1C and ID show di f ferent embodiments of arrangements of functional areas within the functional module of the sensor arrangement ; Figure 2A shows an embodiment of a detector array of a sensor arrangement wherein Figures 2B, 2C, 2D and 2E show di f ferent embodiments of arrangements of functional areas within the functional module of the sensor arrangement ;

Figures 3A and 3B show an embodiment of a sensor arrangement wherein Figure 3A shows a detector array and Figure 3B shows a corresponding functional module ;

Figures 4A and 4B show an embodiment of a sensor arrangement wherein Figure 4A shows a detector array and Figure 4B shows a corresponding functional module ;

Figures 5A and 5B show embodiments of a sensor arrangement in top view;

Figures 6A, 6B, 6C and 6D show embodiments of a sensor arrangement in a sectional view;

Figures 7A and 7B show embodiments of a sensor arrangement in sectional views ;

Figures 8A and 8B show an exemplary embodiment of a sensor arrangement in top view ( Figure 8A) and in sectional view ( Figure 8B ) wherein Figure 8C schematically shows an example of a scene to be detected by the sensor arrangement and Figure 8D schematically shows a spectrum obtained by the sensor arrangement and detection ranges of four functional areas and wherein Figure 8E , 8 F and 8G schematically show an image of the scene obtained from three functional areas of the sensor arrangement ; Figures 9A and 9B show an exemplary embodiment of a sensor arrangement in top view ( Figure 9A) and in sectional view ( Figure 9B ) ;

Figure 10A shows an exemplary embodiment of a sensor arrangement in sectional view and Figure 10B schematically shows a spectrum obtained from the sensor arrangement and three reference spectra ;

Figure 11 shows an embodiment of a method of operating a sensor arrangement ;

Figure 12 shows an embodiment of a method of operating a sensor arrangement ;

Figure 13 shows ten examples of possible numbers of pixels of the detector array and resulting numbers of pixels for the first and second functional areas ;

Figure 14 shows ten examples of possible si zes of the detector array and corresponding numbers of pixels for a pixel si ze of 2 pm and corresponding si zes and numbers of pixels for the first and second functional areas ;

Figure 15 shows ten examples of possible si zes of the detector array and corresponding numbers of pixels for a pixel si ze of 5 pm and corresponding si zes and numbers of pixels for the first and second functional areas ;

Figure 16 shows ten examples of possible si zes of the detector array and corresponding numbers of pixels for a pixel si ze of 20 pm and corresponding si zes and numbers of pixels for the first and second functional areas ; and Figure 17 shows seven examples of possible numbers of pixels of the detector array and resulting numbers of pixels for the first and second functional areas .

In the exemplary embodiments and figures , similar or similarly acting constituent parts are provided with the same reference signs . Generally only the di f ferences with respect to the individual embodiments are described . Unless otherwise speci fied, the description or a part or aspect in one embodiment applies to a corresponding part or aspect in another embodiment as well .

The elements illustrated in the figures and their si ze relationships among one another are not necessarily true to scale . Rather, individual elements or layer thicknesses may be represented with an exaggerated si ze for the sake of better representability and/or for the sake of better understanding .

Figure 1A illustrates an example of a detector array 2 with a plurality of detector pixels 20 where the width-to-length ratio is 1 : 1 so that the number of columns equals the number of rows . Examples of suitable numbers of pixels are illustrated in Figures 13 to 17 .

In Figures IB to ID, the sensor arrangement 1 comprises a functional module 3 with a first functional area 31 and a plurality of second functional areas 32 . The first functional area 31 comprises an interferometer array 4 with a plurality of interferometers arranged side-by-side in a top view . The interferometers may be formed using a crystal that is transmissive to the impinging radiation of interest . For the sake of easier representation the individual interferometers are not explicitly shown in the figures . The interferometers provide di f ferent fixed optical path di f ferences between two interfering beams , so that each row of the detector pixels 2 within the first functional area 31 simultaneously records a complete interferogram . Using the first functional area 31 , the sensor arrangement 1 is configured to calculate a spectrum of the radiation based on a Fourier Trans form calculation of a signal of the detector pixels 20 of the detector array 2 located underneath the first functional area 31 . By averaging over the individual spectra obtained by each row of the detector array 2 assigned to the first functional area 31 , a highly precise spectrum of the radiation, but no spatial resolution, may be obtained . The number of interferometers and the number of assigned detector pixels 20 may be selected during the production of the sensor array based on the required spectral resolution .

The second functional areas 32 provide spatially resolved information . For example , the second functional areas 32 provide images wherein the second functional 32 areas di f fer from one another with respect to the wavelength of maximum sensitivity .

All functional areas 31 , 32 use parts of the same detector array 2 which is configured as a single detector chip . Thus , all functionalities of the sensor arrangement 1 using the signals from the functional areas may be obtained with a single detector chip . This helps to provide a very compact sensor arrangement 1 that can be mounted in a mobile or wearable device , for example in a smartphone or a smartwatch .

In the example of Figure IB, all functional areas have a square shape wherein the area of the first functional area 31 is the largest one . In the example shown, the length of the first functional area 31 is three times larger than the length of a single second functional area 32 . The second functional areas 32 extend along two sides of the first functional area 31 . In this way seven second functional areas 32 and one first functional area 31 together cover the complete detector array 2 , so that all or at least 95% of the detector pixels 2 may be used by the functional areas taken together . However, other numbers of functional areas and/or other types of geometries may also be used for the first and second functional areas 31 , 32 .

The embodiment of Figure 1C essentially corresponds to that of Figure IB . However, the second functional areas 32 are smaller so that adj acent second functional areas 32 do not directly adj oin each other .

In the embodiment of Figure ID, the second functional areas 32 only extend along one side of the first functional area 31 . The first functional area 31 has a rectangular rather than a square shape .

In the embodiments of Figures 2A to 2E , the width-to-length ratio of the detector array 2 is 1 : 2 . In the embodiment of Figure 2B, the first functional area 31 has a square shape . The individual second functional areas 32 likewise have a square shape arranged in a 3x3 grid .

The embodiment of Figure 2C essentially corresponds to that of Figure 2B, but the second functional areas 32 are smaller so that adj acent second functional areas 32 do not directly adj oin each other . In the embodiment of Figure 2D, the first functional area 31 extends along one direction over the entire detector array 2 . Thus , the number of detector pixels 20 arranged in one row and assigned to the first functional area 31 is maximi zed . This helps to improve the spectral resolution . The remaining area of the detector array 2 may be covered by an appropriate number of second functional areas 32 . As an example , 12 second functional areas 32 are provided . As in the other exemplary embodiments , the second functional areas 32 do not necessarily have to have the same si ze and shape .

In the embodiment of Figure 2E , the functional module 3 comprises exactly one first functional area 31 and exactly one second functional area 32 . For example , the first functional area 31 and the second functional area 32 have the same shape , such as a square shape . For example , the second functional area 32 comprises a tunable interference filter so that the wavelength of maximum sensitivity can be tuned between sequentially taken images .

The embodiment of Figures 3A and 3B essentially corresponds to the embodiment of Figure 1A. In this embodiment , however, the first functional area 31 extends over complete columns of the detector array in order to obtain the maximum spectrum resolution as described in connection with Figure 2D .

In the embodiment of Figures 4A and 4B the width-to-length ratio is 1 : 3 . The functional module 3 comprises a third functional area 33 in addition to the first functional area 31 and the second functional areas 32 . The first functional area 31 and the third functional area 33 have the same si ze . The remaining area is divided into the second functional areas 32 , for example into nine second functional areas 32 . For example, the third functional area 33 may be used for direct imaging.

The functional module 3 shown in Figure 4B does not necessarily have to be combined with a detector array having the same width-to-length ratio. Rather, the ratio of the detector array 2 may also be 1:1 or 1:2 in combination with a functional module 3 that is mechanically movable with respect to the detector array 2. Consequently, the user of the sensor arrangement may switch between different operation modes by placing different functional areas over the detector array 2.

The embodiments of Figures 5A and 5B further illustrate different arrangements of first and second functional areas 31, 32. For example, two functional areas 32 of Figure 5A may be used for a stereo imaging. For example, these two second functional areas are arranged at opposite edges of the functional module 3 in order to maximize the distance between these two functional areas. Other ones of the second functional areas 32 may be used as specific multispectral image sensors or polarization-sensitive sensors or designed for a specific time response or gating. If the first functional area 31 is an emitter, for example, the stereo cameras may be specific to the emitter wavelength.

In the embodiment of Figure 5B, the second functional areas 32 differ from one another with respect to their size. The shapes of the functional areas may likewise differ from one another. The sizes may be varied to compensate for lower sensitivity and/or light transmission for different detection channels with different wavelengths. Furthermore, the arrangement may be used to compensate for optical point spread function requirements or for coarser digitalization requirements while keeping the same field of view for the functional areas . Using the di f ferent functional areas , di f ferent devices may be combined within one semiconductor chip, for example a combination including a single photon avalanche diode ( SPAD) and/or an indirect time-of- f light ( iToF) capability and/or an imaging capability .

Figures 6A to 6D illustrate di f ferent arrangements of elements on top of the detector array 2 wherein the setup may vary from functional area to functional area .

In the embodiment of Figure 6A, a functional element 30 of a functional area is the element closest to the detector array 2 . On the side of the functional element 30 remote from the detector array 2 , a spacer 44 , an optics 42 and a filter 43 are arranged . In particular, at least two or more functional areas may be provided with an individual optics .

The order of the elements , however, may vary . For example , Figure 6B shows an embodiment where the spacer 44 is arranged between the functional element 30 and the detector array 2 .

In the embodiment of Figure 60, a spacer 44 and an optics 42 are arranged between the detector array 2 and the functional element 30 . In all of the above embodiments one or more of the components may be omitted . For example , Figure 6D shows an exemplary embodiment dispensing with an optics 42 and a filter 43 so that only a spacer 44 and a functional element 30 are arranged on the detector array 2 .

Figure 7A illustrates an exemplary embodiment of a sensor arrangement 1 in sectional view wherein a first functional area 31 and a second functional area 32 are shown . The first functional area 31 comprises a functional element 30 , a spacer 44 , an optics 42 and a filter 43 . The second functional area 32 comprises a spacer 44 , an optics 42 and a filter 43 .

The exemplary embodiment of Figure 7B essentially corresponds to that of Figure 7A. However, the lateral extent of the functional module 3 is larger than that of the detector array 2 , for example by a factor of 2 . The functional module 3 is movable with respect to the detector array 2 as illustrated by arrow 49 . Of course , a movable functional module 3 may also apply for functional areas 31 , 32 have other configurations or functions .

Figures 8A to 8E illustrate an example of a sensor arrangement 1 which may for example be used to identi fy di f ferent light sources in ambient light . In top view, the sensor arrangement of Figure 8A essentially corresponds to that shown in Figure ID . The sensor arrangement 1 comprises one functional area 31 comprising an interferometer array 4 as functional element and four second functional areas 32a, 32b, 32c, 32d . Using di f ferent filters 43 , for example interference filters , the second functional areas 32 di f fer from one another with respect to the wavelength of maximum sensitivity . A further filter 45 may block radiation outside of the spectral range of interest , for instance infrared or ultraviolet radiation .

Figure 8C schematically shows a scene to be detected . Exemplarily the scene comprises eight LED light sources 61 and two non-LED light sources 62 . Light cones 63 illustrate the light of the light sources illuminating a wall . The color temperature of the light sources increases from warm white on the left-hand side toward cold white on the right-hand side .

Figure 8D shows the spectrum 71 obtained by the first functional area 31 . Figure 8D further illustrates a first detection band 51 , a second detection band 52 , a third detection band 53 and a fourth detection band 54 corresponding to the second functional areas 32a, 32b, 32c and 32d respectively .

The second functional area 32a with the first detection band 51 having the shortest wavelength predominantly images the light sources on the right-hand side ( Figure 8E ) .

Accordingly, Figure 8G illustrating the image of the second functional area 32d having the detection band with the largest wavelength predominantly images the light sources on the left-hand side .

The second functional area 32c, sensitive in the third detection band 53 , predominantly images the light sources in the center of the scene , as shown in Figure 8 F .

In this exemplary embodiment the first functional area 31 delivers a fine spectral resolution average spectrum of the scene without any spatial resolution . This data may be used to predefine the spectral range and/or the position and/or quantity parameters for regions of the second functional areas 32 . Furthermore , the spectrum obtained from the first functional area 31 helps to predict di f ferent types of light sources within the scene . The second functional areas 32 provide images with spatial resolution and allow to identi fy the positions of the light sources within the scenes and to assign the spectral contributions within the spectrum to the individual light sources , so that it may also be possible to distinguish between the LED light sources 61 and the non-LED light sources 62 .

Figures 9A and 9B illustrate a further exemplary embodiment of a sensor arrangement 1 essentially ful filling the same function as the exemplary embodiment described in connection with Figures 8A to 8G . In contrast to the previous exemplary embodiment , the sensor arrangement 1 comprises only one second functional area 32 . Consequently, the second functional area 32 has a larger area than one individual second functional area 32 of Figure 9A. Thus , with the same detector array 2 the spatial resolution of the images obtained within the second functional area 32 is increased .

Data for di f ferent detection bands may be obtained by a tunable interference filter 41 so that images with two , three , four or more di f ferent detection bands may be sequentially taken by the detector array 2 .

Figures 10A and 10B illustrate an exemplary embodiment of a sensor arrangement 1 that can be used in sensing reflected light from human skin .

The sensor arrangement 1 essentially corresponds to that described in connection with Figures 8A to 8G wherein the detection bands of the second functional areas 32 are speci fically designed for the characteristic spectrum of light reflected by human skin .

In Figure 10B curve 72 represents a reference spectrum characteristic of an arm . Curve 73 corresponds to a characteristic spectrum of a finger and curve 74 represents a reference spectrum characteristic of a lip . In this case in particular the second detection band 52 allows to clearly distinguish between an arm, a finger or a lip . Spectrum 71 , obtained by the first functional area 31 , is exemplarily similar to the spectrum of a finger .

In this exemplary embodiment the first functional area 31 delivers a fine spectral resolution average spectrum and predefines the spectral range and/or position and/or quantity parameters for regions of the second functional areas 32 . During operation of the sensor arrangement , the information from the first functional area 31 is used for a sample recognition based on an exact spectral profile , while the information from the second functional areas 32 is used for consequent fast monitoring .

Figure 11 illustrates an exemplary embodiment of a method of operating a sensor arrangement which may be configured as described in connection with the previous exemplary embodiments .

In a step 81 , an initial image is acquired . This initial image may be either obtained by one of the second functional areas 32 or by an additional image sensor .

In a step 82 a detailed spectrum is obtained by the first functional area 31 .

In a step 83 a desired spectral sensitivity based on the spectrum obtained from the first functional area 31 is evaluated . In a step 84 , individual images using application-relevant areas from the range of the second functional areas 32 are acquired .

In a step 85 , the steps starting from step 81 or 82 are repeated depending on factors such as target results or acquisition mode or motion trigger .

Figure 12 illustrates a further exemplary embodiment of a method wherein the workflow is illustrated as a function of time t .

The figure illustrates an acquisition layer 91 and a processing layer 92 . The acquisition layer 91 includes the acquisition of the first functional area 94 and the acquisition for the second functional area 95 . Element 93 represents a monitor, for example of a spectral change . Element 96 represents an estimation of appropriate spectral ranges for the second functional areas 32 based on the high resolution spectrum obtained from the first functional area 31 . Element 97 represents an application-speci fic comparison . Element 98 represents the acquisition of the selected second functional areas 32 which are further processed as illustrated by process range 99 .

Figure 13 illustrates ten examples of possible detector arrays 2 having a square shape wherein the functional module comprises one first functional area 31 and seven second functional areas 32 , as described in connection with Figure IB . The table includes the number of pixels of the full detector array NOP_FD, the number of pixels for the first functional area NOP_1 and the number of pixels of one second functional area NOP 2 . Figure 14 additionally includes the si ze of the full detector array S_FD, the si ze of the first functional area S_1 and the si ze of an individual second functional area S_2 , assuming a pixel si ze of 2 pm . For lines 7 to 9 of this table a minimum spatial resolution of 256 along one direction of the second functional areas 32 may be obtained with a detector si ze of at most 4x4 mm so that the sensor arrangement 1 can be conveniently placed within a mobile device .

For other applications , however, smaller resolutions or larger detector array si zes may also apply .

The table of Figure 15 corresponds to that of Figure 14 except that the pixel si ze is 5 pm . With a length of the detector array of at most 5 mm, the maximum resolution for the second functional areas 32 is reduced to 256 pixels per direction .

The table of Figure 16 essentially corresponds to that of Figure 14 , except that the pixel si ze is 20 pm .

In this case , the maximum resolution along one direction of the second functional area 32 is 80 i f the maximum si ze of the detector array 2 is below 10 mm .

Figure 17 illustrates suitable examples for the application described in connection with Figures 10A to 10B .

As described in connection with Figures 14 to 16 , the si ze of the full detector array and the first and second functional areas 31 , 32 depends on the si ze of the individual detector pixel . This patent application claims the priority of German patent application 10 2023 105 170 . 9 , the disclosure content of which is hereby incorporated by reference . The invention described herein is not restricted by the description given with reference to the exemplary embodiments . Rather, the invention encompasses any novel feature and any combination of features , including in particular any combination of features in the claims , even i f this feature or this combination is not itsel f explicitly indicated in the claims or exemplary embodiments .

References

1 sensor arrangement

2 detector array

20 detector pixel

3 functional module

30 functional element

31 first functional area

32 second functional area

32a, 32b, 32c, 32d second functional area

33 third functional area

4 interferometer array

41 tunable interference filter

42 optics

43 filter

44 spacer

45 further filter

49 arrow

51 first detection band

52 second detection band

53 third detection band

54 fourth detection band

61 LED light source

62 non-LED light source

63 light cone

71 spectrum

72 reference spectrum arm

73 reference spectrum finger

74 reference spectrum lip

81 , 82 , 83 , 84 , 85 step

91 acquisition layer

92 processing layer

93 monitor 94 acquisition of first functional area

95 acquisition of second functional area

96 estimation

97 comparison 98 get data from second functional areas

99 process range

NOP_FD number of pixels of the full detector array

NOP_1 number of pixels of first functional area NOP_2 number of pixels of second functional area

S_FD si ze of full detector array

S_1 si ze of first functional area

S 2 si ze of second functional area

Claims

1. A sensor arrangement (1) comprising a detector array (2) and a functional module (3) comprising a plurality of functional areas (31, 32) , wherein

- at least one of the functional areas (31, 32) overlaps with the detector array when seen in a vertical direction onto the detector array;

- the functional areas (31, 32) are arranged side-by-side when seen in the vertical direction;

- the sensor arrangement (1) is configured to perform a spectral calculation of a radiation impinging onto a first functional area (31) of the plurality of functional areas (31, 32) .

2. The sensor arrangement according to claim 1, wherein the first functional area (31) comprises an interferometer array (4) with a plurality of interferometers arranged side-by-side when seen in the vertical direction.

3. The sensor arrangement according to claim 1 or 2, wherein the sensor arrangement (1) is configured to calculate a spectrum of the radiation based on a Fourier Transform calculation of a signal of detector pixels (20) of the detector array (2) that are assigned to the first functional area ( 31 ) .

4. The sensor arrangement according to any of the preceding claims , wherein at least along one direction at least 150 detector pixels (20) are assigned to the first functional area (31) .

5. The sensor arrangement according to any of the preceding claims , wherein at least one second functional area (32) of the plurality of functional areas (31, 32) is configured for spectral or multispectral imaging.

6. The sensor arrangement according to claim 5, wherein at least three of the second functional areas (32) mutually differ from one another with respect to a wavelength of maximum sensitivity.

7. The sensor arrangement according to claim 5 or 6, wherein at least one second functional area (32) comprises a tunable interference filter (41) .

8. The sensor arrangement according to any of claims 5 to 7, wherein the second functional areas (32) in each case are assigned to at least 15 detector pixels along one direction of the detector array.

9. The sensor arrangement according to any of the preceding claims , wherein at least one of the functional areas (31, 32) is configured for direct imaging, time-resolved detection, polarization sensing, stereo imaging or light emission.

10. The sensor arrangement according to any of the preceding claims , wherein the functional module (3) is movable with respect to the detector array (2) .

11. The sensor arrangement according to any of the preceding claims , wherein all detector pixels (2) of the detector array (20) are formed in a single semiconductor chip.

12. The sensor arrangement according to any of the preceding claims , wherein at least two functional areas (31, 32) differ from one another with respect to their size.

13. The sensor arrangement according to any of the preceding claims , wherein the sensor arrangement (1) is configured for a mobile or wearable device.

14. A method of operating a sensor arrangement according to any of the preceding claims, comprising the steps of: a) acquiring a spectrum using the first functional area (31) ; and b) acquiring at least one image using at least one second functional area (32) of the functional module (3) .

15. The method of claim 14, wherein acquiring at least one image using at least one second functional area is based on the spectrum.

16. The method of claim 14 or 15, wherein in step b) the at least one second functional area used for acquisition is selected based on its spectral sensitivity .