Multi-spectral optical sensor

Abstract

A multi-spectral optical sensor (100) for detecting incident radiation (R) having a wavelength spectrum is specified, wherein the multi-spectral optical sensor (100) comprises: - a semiconductor chip (1) comprising an array of detector segments (10), wherein each of the detector segments (10) comprises an array of detector subregions (11a, 11b, 11c, 11d, 11e, 11f, 11g, 11h, 11i), - an array of optical filters (20), wherein each of the optical filters (20) is assigned to one of the detector segments (10), and - telecentric optical means (30) comprising an array of metalenses (31), wherein each of the metalenses (31) is assigned to one of the optical filters (20) and the array of optical filters (20) is arranged between the array of detector segments (10) and the array of metalenses (31).

Description

[0001] 2024PF01291 November 24 , 2025

[0002] P2024 , 0933 WO N

[0003] - 1 -

[0004] Description

[0005] MULT I -SPECTRAL OPTICAL SENSOR

[0006] The present disclosure relates to a multi-spectral optical sensor, which for example is suitable for being integrated into an electronic device like a smartphone in order to adj ust a captured image of a scene for the ef fects of ambient illumination on di f ferent parts of the scene .

[0007] A current technology as described in document WO 2022 / 074047 , for example , suggests an array of convex lenses for an optical multi-spectral sensor in order to proj ect incident radiation on a detector array of the optical multi-spectral sensor . In order to reduce angular dependent ef fects , a telecentric optic can be used, which however requires a multilens system for each spectral channel . Due to method requirements in case of molding and curing, for example , the convex lenses are equal for each spectral channel , which causes chromatic aberration ef fects . In addition, misalignment of the lenses in front of the detector array causes a di f ferent lateral resolution, blur and distortion at each of the spectral channels .

[0008] One obj ect inter alia is to speci fy a multi-spectral optical sensor providing for improved optical properties . This obj ect is achieved inter alia by the multi-spectral optical sensor according to the independent claim . Further embodiments and further developments of the multi-spectral optical sensor are the subj ect-matter of the dependent claims .

[0009] According to at least one embodiment of a multi-spectral optical sensor, which is suitable for detecting incident 2024PF01291 November 24 , 2025

[0010] P2024 , 0933 WO N

[0011] 2 radiation having a wavelength spectrum, the multi-spectral optical sensor comprises a semiconductor chip . It is possible for the semiconductor chip to be a multi-pixel chip . The semiconductor chip may comprise an array of pixels or detector segments , wherein each of the pixels or detector segments comprises an array of subpixels or detector subregions . In the context of the present application, the term "array" can denote a regular arrangement of elements , for example a row-like , columnar or matrix-like arrangement of elements . For example , all detector segments have the same arrangement and number of detector subregions .

[0012] According to at least one embodiment , the multi-spectral optical sensor comprises an array of optical filters . Each of the optical filters can be assigned to one of the detector segments . And each of the detector segments can be assigned to one of the optical filters . For example , the assignment of the optical filters and detector segments is a one-to-one correlation .

[0013] According to at least one embodiment , the multi-spectral optical sensor comprises telecentric optical means . In the context of the present application, the term "telecentric optical means" can denote optical means providing for an essentially similar angular distribution of radiation of centrally and peripherally arranged detector subregions , wherein "essentially" means within common production tolerances . In other words , independent of the position an essentially similar angular distribution of radiation can be achieved for all detector subregions by means of the telecentric optical means . For example , the telecentric optical means comprise optical means for collimating the incident radiation . 2024PF01291 November 24 , 2025

[0014] P2024 , 0933 WO N

[0015] - 3 -

[0016] According to at least one embodiment , the telecentric optical means comprise an array of metalenses . In the context of the present application, the term "metalens" can denote a non- refractive optical means . For example , the above-mentioned optical function of the telecentric optical means , which includes providing for an essentially similar angular distribution of radiation of centrally and peripherally arranged detector subregions , can be ful filled by the array of metalenses . For this purpose , the metalenses can comprise optical means for collimating the incident radiation . The metalenses can have microscale si zes , for example diameters ranging from 50 to 200 pm . Moreover, the metalenses can in each case have a flat , for example uncurved shape , which allows to overcome spherical aberration . Using the array of metalenses for the telecentric optical means helps to reduce sensor si ze and to improve optical properties for example due to the reduced number of lenses per channel and thus reduced misalignment as well as the suppressed spherical aberration .

[0017] According to at least one embodiment , each of the metalenses is assigned to one of the optical filters . And each of the optical filters can be assigned to one of the metalenses . For example , the assignment of the optical filters and metalenses is a one-to-one correlation .

[0018] According to at least one embodiment , each of the metalenses is assigned to one of the detector segments . And each of the detector segments can be assigned to one of the metalenses . For example , the assignment of the detector segments and metalenses is a one-to-one correlation .

[0019] According to at least one embodiment , the array of optical filters is arranged between the array of detector segments 2024PF01291 November 24 , 2025

[0020] P2024 , 0933 WO N

[0021] 4 and the array of metalenses . The multi-spectral optical sensor may have a hori zontal main extension plane , wherein the arrays are arranged one above the other in a direction running oblique , for example perpendicular, to the main extension plane .

[0022] According to at least one embodiment , a multi-spectral optical sensor for detecting incident radiation having a wavelength spectrum comprises :

[0023] - a semiconductor chip comprising an array of detector segments , wherein each of the detector segments comprises an array of detector subregions ,

[0024] - an array of optical filters , wherein each of the optical filters is assigned to one of the detector segments , and

[0025] - telecentric optical means comprising an array of metalenses , wherein each of the metalenses is assigned to one of the optical filters and the array of optical filters is arranged between the array of detector segments and the array of metalenses .

[0026] According to at least one embodiment or configuration, the metalenses in each case comprise a pattern of pattern elements , wherein the pattern elements have si zes smaller than wavelengths of the speci fic wavelength spectrum of the incident radiation . For example , the pattern elements can have nanoscale si zes having diameters which vary from 50 to 220 nm, for example .

[0027] According to at least one embodiment or configuration, each pattern changes a phase profile of the incident radiation such that the incident radiation is di f fracted . For example , every pattern or metalens can control radiation wavefronts such that the incident radiation is collimated . 2024PF01291 November 24, 2025

[0028] P2024, 0933 WO N

[0029] - 5 -

[0030] According to at least one embodiment or configuration, the pattern elements of each pattern vary in size and / or shape. For example, the sizes and / or shapes of the pattern elements are adjusted such that the above-mentioned optical function can be achieved.

[0031] According to at least one embodiment or configuration, the patterns of the metalenses are different. For example, the patterns can be adjusted to spectral characteristics of the optical filters, which can be different.

[0032] According to at least one embodiment or configuration, the metalenses have a single layer or multilayer structure. Each pattern can be formed from a single layer or a multilayer of (a) material (s) provided for producing the metalenses. For example, the single layer structure allows for a small thickness of the metalenses. The multilayer structure can allow for more complex designs of the metalenses.

[0033] According to at least one embodiment or configuration, the pattern elements comprise or consist of a material having a refractive index which is not matched to the refractive index of a surrounding material, which for example directly surrounds the pattern elements. In other words, it can be intended for the material of the pattern elements and the surrounding material to be different, for example the difference being as high as possible. Suitable materials for the pattern elements are for example TiO2, SiO2, GaN, SiN or glass for a wavelength spectrum in the visible spectral range .

[0034] According to at least one embodiment or configuration, the telecentric optical means comprise at least one transparent 2024PF01291 November 24 , 2025

[0035] P2024 , 0933 WO N

[0036] 6 substrate and the array of metalenses is arranged at a surface of the at least one transparent substrate . In the context of the present application, "transparent" can mean transmissive to the incident radiation . For example , it is possible for the array of metalenses to be applied to the at least one transparent substrate . Alternatively, the array of metalenses may be formed into the at least one transparent substrate .

[0037] The array of metalenses can be produced by a lithographic process , for example , allowing for mass production of fering low cost products .

[0038] According to at least one embodiment or configuration, the telecentric optical means are directly arranged on the array of filters . This arrangement enables a wafer scale package . The telecentric optical means may be arranged on the array of filters such that the array of metalenses faces or is in contact with the array of filters or a composite of the array of filters and semiconductor chip . In this case , the array of filters or detector segments are arranged out of focus , which results in what can be called an out-of- focus image . Thus , the radiation is blurred in the plane of the array of optical filters or detector segments . Alternatively, the telecentric optical means may comprise two transparent substrates and the array of metalenses can be arranged between the two transparent substrates . In this case , the array of metalenses is not in direct contact with the array of filters or composite of the array of filters and semiconductor chip . The array of optical filters or detector segments may be arranged in a focal plane of the array of metalenses , which results in what can be called an in- focus image , or may be arranged out 2024PF01291 November 24 , 2025

[0039] P2024 , 0933 WO N

[0040] - 7 - of the focal plane , which results in what can be called an out-of- focus image .

[0041] According to at least one embodiment or configuration, the telecentric optical means comprise an array of apertures , wherein each of the apertures is assigned to one of the metalenses . The incident radiation may enter the telecentric optical means through the array of apertures . For example , a radiation-blocking layer is arranged on a side of the telecentric optical means or transparent substrate facing away from the array of metalenses , wherein the radiationblocking layer comprises transmissive windows , which form the apertures .

[0042] According to at least one embodiment or configuration, the multi-spectral optical sensor comprises a support , wherein the telecentric optical means are mounted on the support . The support may provide for a gap between the telecentric optical means and the array of filters . The support may comprise , or be formed from, a plastics material such as a thermosetting polymer material or a thermoplastic polymer material . The support may comprise , or be formed from, an opaque material . The support may comprise one or more opaque walls preventing optical crosstalk between adj acent detector segments .

[0043] According to at least one embodiment or configuration, the optical filters exhibit transmission spectra overlapping with absorption spectra of the detector subregions of the assigned detector segments . In other words , the detector subregions may have sensitivity in a passband of the assigned optical filter . For example , the detector subregions can comprise active zones including bandgaps matching the passbands of the assigned optical filters . 2024PF01291 November 24 , 2025

[0044] P2024 , 0933 WO N

[0045] 8

[0046] According to at least one embodiment or configuration, at least two of the optical filters have di f ferent transmission spectra . Thus , each detector segment may be considered to act as a monochromatic detector segment . For example , the transmission spectra of at least three of the optical filters are suitable for tristimulus detection .

[0047] According to at least one embodiment or configuration, each optical filter comprises an interference filter . Advantageously, the angle-dependent ef fects of the interference filter can be compensated for by the telecentric optical means .

[0048] According to at least one embodiment or configuration, the multi-spectral optical sensor comprises di f fusing means . For example , the di f fusing means can help to provide or at least approximate a Gaussian profile of the radiation in the plane of the detector segments .

[0049] According to at least one embodiment or configuration, the semiconductor chip is a monolithic semiconductor chip and the optical filters are arranged on a front surface of the semiconductor chip . In the context of the present application, "monolithic" can mean " formed as one piece" .

[0050] For example , the multi-spectral optical sensor is suited for obtaining spectral information relating to di f ferent parts or sectors of a scene captured by an image sensor or a camera . So-called gradient white balancing may be conducted based on the spectral information to adj ust the coloration of an image of the scene , for example to more accurately reproduce the image of the scene . 2024PF01291 November 24 , 2025

[0051] P2024 , 0933 WO N

[0052] - 9 -

[0053] According to at least one embodiment or configuration, at least some detector subregions of every detector segment are assigned to di f ferent incidence directions or sectors of a scene . Moreover, at least some detector subregions of di f ferent detector segments can be assigned to the same incidence direction or sector of a scene . The detected signals may be used to reconstruct the spectrum of the radiation incident on the multi-spectral optical sensor from di f ferent incidence directions or sectors of a scene .

[0054] The multi-spectral optical sensor is suitable for consumer applications like mobile phones , notebooks or tablets or automotive applications .

[0055] Further preferred embodiments and further developments of the multi-spectral optical sensor will become apparent from the exemplary embodiments explained below in conj unction with the Figures .

[0056] Figure 1A shows a schematic sectional view of a multi- spectral optical sensor according to an exemplary embodiment , and Figure IB shows a plan view of a part of the multi-spectral optical sensor according to the exemplary embodiment shown in Figure 1A,

[0057] Figure 2A shows a schematic perspective view of an example of a metalens , and Figure 2B shows a part of the metalens shown in Figure 2A,

[0058] Figure 3 shows a schematic sectional view of a comparative example of a multi-spectral optical sensor, 2024PF01291 November 24 , 2025

[0059] P2024 , 0933 WO N

[0060] - 10 -

[0061] Figure 4 shows an exemplary embodiment of an electronic device comprising a multi-spectral optical sensor as described herein,

[0062] Figures 5 to 7 show schematic sectional views of multi- spectral optical sensors according to further exemplary embodiments , and

[0063] Figure 8A illustrates an in- focus arrangement of a multi- spectral optical sensor speci fied herein, and Figure 8B shows an out-of- focus arrangement of a multi-spectral optical sensor speci fied herein .

[0064] Identical , equivalent or equivalently acting elements are indicated with the same reference numerals in the figures . The figures , which are schematic illustrations , are not necessarily true to scale . Comparatively small elements and particularly layer thicknesses can rather be illustrated exaggeratedly large for the purpose of better clari fication .

[0065] In connection with Figures 1A and IB, an exemplary embodiment of a multi-spectral optical sensor 100 is described . The multi-spectral optical sensor 100 is suitable for detecting incident radiation R from di f ferent incidence directions or sectors of a scene and gaining spectral information of the di f ferent incidence directions or sectors .

[0066] As becomes evident from Figures 1A and IB, the multi-spectral optical sensor 100 comprises a semiconductor chip 1 , which is a multi-pixel chip, for example . It is possible for the semiconductor chip 1 to contain or to be formed from silicon . 2024PF01291 November 24 , 2025

[0067] P2024 , 0933 WO N

[0068] - 11 -

[0069] Moreover, the multi-spectral optical sensor 100 comprises an array of optical filters 20 arranged on the semiconductor chip 1 . For example , each of the optical filters 20 comprises an interference filter . The semiconductor chip 1 can be a monolithic semiconductor chip, wherein the optical filters 20 are arranged on a front surface 1A of the semiconductor chip 1 .

[0070] Furthermore , the multi-spectral optical sensor 100 comprises telecentric optical means 30 arranged on the array of optical filters 20 and comprising an array of metalenses 31 . In addition, the multi-spectral optical sensor 100 may comprise a carrier 40 , wherein the semiconductor chip 1 is arranged on the carrier 40 . For example , the carrier 40 is or comprises a PCB (printed circuit board) .

[0071] Besides , the multi-spectral optical sensor 100 may comprise a support 50 , wherein the telecentric optical means 30 are mounted on the support 50 . The support 50 can provide for a gap g between the telecentric optical means 30 and the array of optical filters 20 . The support 50 may comprise , or be formed from, a plastics material as mentioned above .

[0072] Moreover, the support 50 may comprise , or be formed from, an opaque material , which may prevent lateral incidence of radiation . A combination of the telecentric optical means 30 , the carrier 40 and the support 50 may constitute a housing with a cavity, wherein the semiconductor chip 1 and the array of optical filters 20 are arranged in the cavity .

[0073] The semiconductor chip 1 comprises an array of pixels or detector segments 10 , wherein each of the optical filters 20 is assigned to one of the detector segments 10 and each of the detector segments 10 is assigned to one of the optical 2024PF01291 November 24, 2025

[0074] P2024, 0933 WO N

[0075] - 12 - filters 20, for example in a unique way or one-to-one correlation. Thus, the number of optical filters 20 and the number of detector segments 10 can be identical.

[0076] Each of the metalenses 31 is assigned to one of the optical filters 20 and each of the optical filters 20 is assigned to one of the metalenses 31, for example in a unique way or one- to-one correlation. Thus, the number of optical filters 20 and the number of metalenses 31 can be identical.

[0077] Accordingly, each of the metalenses 31 is assigned to one of the detector segments 10 and each of the detector segments 10 is assigned to one of the metalenses 31, for example in a unique way or one-to-one correlation. Thus, the number of detector segments 10 and the number of metalenses 31 can be identical .

[0078] Each of the pixels or detector segments 10 comprises an array of subpixels or detector subregions Ila, 11b, 11c, lid, lie, llf, 11g, llh, Hi, wherein the arrangement and number of subregions Ila, 11b, 11c, lid, He, Ilf, 11g, llh, Hi can be the same for every detector segment 10.

[0079] The optical filters 20 can have different transmission spectra so that the subregions Ha, 11b, He, lid, He, Ilf, llg, llh, Hi of different detector segments 10 detect different spectral portions of the incident radiation R. For example, the transmission spectra of at least three of the optical filters 20 are suitable for tristimulus detection. The transmission spectra of the optical filters 20 overlap with absorption spectra of the detector subregions Ha, Hb, He, Hd, He, Ilf, 11g, llh, Hi of the assigned detector segments 10. In other words, the detector subregions Ha, 2024PF01291 November 24, 2025

[0080] P2024, 0933 WO N

[0081] - 13 -

[0082] 11b, 11c, lid, lie, Ilf, 11g, llh, Hi have sensitivity in a passband of the assigned optical filter 20. For example, the detector subregions Ila, 11b, 11c, lid, He, Ilf, 11g, llh, Hi can comprise active zones including bandgaps matching the passbands of the assigned optical filters 20.

[0083] Based on the example of a metalens shown in Figure 2A, characteristics of the metalenses 31 of the telecentric optical means 30 are described. The metalenses 31 in each case comprise a pattern of pattern elements 31A, wherein the pattern elements 31A have sizes smaller than wavelengths Al, A2, A3, A4 and A5 of the wavelength spectrum of the incident radiation R. The sizes and / or shapes of the pattern elements 31A are adjusted such that the optical function explained in connection with Figure 3 can be achieved. For example, the pattern elements 31A have nanoscale sizes having diameters dl which vary from 50 to 220 nm, for example. The pattern elements 31A of each pattern can vary in size and / or shape. Moreover, the patterns of the metalenses 31 can be different. For example, the patterns can be adjusted to spectral characteristics of the optical filters 20. The metalenses 31 can have microscale sizes, for example having diameters d2 ranging from 50 to 200 pm.

[0084] The telecentric optical means 30 of the embodiment shown in Figures 1A and IB comprise a transparent substrate 32, for example a glass substrate, and the array of metalenses 31 is arranged at a surface of the transparent substrate 32 facing the array of optical filters 20. The array of metalenses 31 or the pattern of pattern elements 31A can be directly applied to the transparent substrate 32. For example, the pattern elements 31A can be formed from a single material layer. Alternatively, it is possible to form the pattern 2024PF01291 November 24 , 2025

[0085] P2024 , 0933 WO N

[0086] 14 elements 31A from multiple material layers i f a more complex structure is intended . As mentioned above , suitable materials for the pattern elements 31A are for example TiO2 , SiO2 , GaN, SiN or glass for a wavelength spectrum in the visible spectral range .

[0087] Moreover, the telecentric optical means 30 comprise an array of apertures 33 , wherein each of the apertures 33 is assigned to one of the metalenses 31 . The incident radiation R enters the telecentric optical means 30 through the array of apertures 33 . For example , a radiation-blocking layer 34 is arranged on a side of the telecentric optical means 30 or transparent substrate 32 facing away from the array of metalenses 31 , wherein the radiation-blocking layer 34 comprises transmissive windows , which form the apertures 33 .

[0088] As becomes evident from Figure 1A, the array of optical filters 20 and the array of detector segments 10 are in each case arranged out of a focal plane B of the array of metalenses 31 . Thus , the radiation R incident on the array of optical filters 20 or detector segments 10 is out of focus , which results in what can be called an out-of- focus image . The ef fects related to the out-of- focus image are described in connection with Figures 8A and 8B .

[0089] Based on the comparative example of Figure 3 , which shows a multi-spectral optical sensor 100 ' comprising a refractive multilens system 30 ' for each spectral channel , the optical function of the telecentric optical means 30 including the array of non-ref ractive metalenses 31 is explained . Radiation R propagating along an incidence direction parallel to an optical axis A ( for the optical axis A see Figure 1A) of the multi-spectral optical sensor 100 is transmitted through the 2024PF01291 November 24, 2025

[0090] P2024, 0933 WO N

[0091] - 15 - telecentric optical means 30 without deflection (see central solid arrow of Figure 3) and projected on a centrally arranged detector subregion lie (see Figure IB) . Radiation R propagating along an incidence direction oblique to the optical axis A is transmitted through the telecentric optical means 30 with deflection (see differently dashed arrows of Figure 3) and projected on one of the peripherally arranged detector subregions Ila, 11b, 11c, lid, Ilf, 11g, llh, Hi (see Figure IB) .

[0092] While in the comparative example of Figure 3, a first microlens array 31A' and a second microlens array 31B' are used, wherein the second microlens array 31B' is provided to reduce an aperture angle of the convergent radiation received from the first microlens array 31A' , in the embodiments of the present application the same effect can be achieved by the array of metalenses 31 of the telecentric optical means 30, wherein the metalenses 31 comprise collimating optical means. As a consequence, the optical function of the telecentric optical means 30, which includes providing for an essentially similar angular distribution of radiation of centrally and peripherally arranged detector subregions Ila, 11b, 11c, lid, He, Ilf, Hg, llh, Hi, can be fulfilled. This is advantageous where the optical transmission spectra of the optical filters 20 are dependent on the angle of incidence of the radiation incident on the optical filters 20, for example where the optical filters 20 comprise interference filters, to ensure that the spectral portions matching the transmission spectra may be transmitted regardless of the initial direction of propagation.

[0093] The patterns of the metalenses 31 may change a phase profile of the incident radiation R such that the incident radiation 2024PF01291 November 24, 2025

[0094] P2024, 0933 WO N

[0095] - 16 -

[0096] R is diffracted. For example, every pattern or metalens 31 can control radiation wavefronts such that the incident radiation R is collimated in a way as demonstrated in connection with the convex lenses of the first and second microlens arrays 31A' , 31B' .

[0097] In comparison to the convex lenses of the microlens arrays 31A' , 31B' , however, the metalenses 31 have a flat, uncurved shape, which allows to reduce effects of spherical aberration and helps to reduce sensor size. Moreover, the reduced number of lenses reduces misalignment effects.

[0098] In summary, the multi-spectral optical sensor 100 described herein has improved properties including improved optical properties .

[0099] Figure 4 shows an exemplary embodiment of an electronic device 200 comprising a multi-spectral optical sensor 100 as described herein. The electronic device 200 is a mobile phone, for example, including a camera (not shown) . A field of a scene C captured by the camera can be divided into a plurality of sectors Sa, Sb, Sc, Sd, Se, Sf, Sg, Sh, Si, wherein the different subregions Ila to Hi of every detector segment 10 are provided to detect radiation from different sectors Sa to Si or incidence directions Da, Db, De, Dd, De, Df, Dg, Dh, Di, while the corresponding subregions Ila to Hi of different detector segments 10 are provided to detect radiation from the same sectors Sa to Si or incidence directions Da, Db, De, Dd, De, Df, Dg, Dh, Di. For example, the subregions Ha of all detector segments 10 are provided to detect radiation from sector Sa or incidence direction Da, while the subregions Ha to Hi of one detector segment 10 are provided to detect radiation from different sectors Sa to 2024PF01291 November 24 , 2025

[0100] P2024 , 0933 WO N

[0101] - 17 -

[0102] Si or incidence directions Da to Di . Since every optical filter 20 may have a di f ferent passband, the radiation detected by corresponding detector subregions of di f ferent detector segments 10 are representative of a wavelength spectrum of the radiation R incident on the multi-spectral optical sensor 100 from the scene C along the same direction of incidence associated with the corresponding detector subregions of the di f ferent detector segments 10 .

[0103] For example , the electronic device 200 includes a processing unit (not shown) , which is configured to process signals from the multi-spectral optical sensor 100 and the camera . The processing unit can be configured to conduct an ambient light source classi fication for every sector Sa to Si or direction of incidence Da to Di . In addition, the processing unit can be configured to adapt an image of the scene C captured by the camera based upon the ambient light source classi fication conducted for every sector Sa to Si or direction of incidence Da to Di . Speci fically, the processing unit is configured to adapt the sensed image by white-balancing the image based upon one or more parameters of the ambient light source classi fication for each direction, for example by gradient white-balancing the image based upon one or more parameters of the ambient light source classi fication for each incidence direction .

[0104] In connection with Figures 5 to 7 , further exemplary embodiments of a multi-spectral optical sensor 100 are described, wherein the designs of these exemplary embodiments enable wafer scale packages . In the context of the present application, the term "wafer scale package" may denote a package fabricated from a wafer composite rather than by a mounting process of single components . The wafer scale 2024PF01291 November 24 , 2025

[0105] P2024 , 0933 WO N

[0106] - 18 - packages can be produced in a more ef ficient , for example cost ef ficient way . Moreover, the wafer scale packages may have higher alignment accuracies of their components , involving better optical properties as well as reduced package si zes .

[0107] Figures 5 and 6 show exemplary embodiments of a multi- spectral optical sensor 100 comprising telecentric optical means 30 , which include in each case an array of metalenses 31 sandwiched between two transparent substrates 32 , which may be glass substrates , for example . The telecentric optical means 30 in each case are directly arranged on a composite including the semiconductor chip 1 and the array of optical filters 20 , wherein "directly" may mean "without any gap" , especially any gap causing deflection of radiation .

[0108] According to the exemplary embodiment of Figure 5 , the array of optical filters 20 or the array of detector segments 10 are arranged out of the focal plane B of the array of metalenses 31 . In particular, every optical filter 20 or detector segment 10 is arranged out of focus of its corresponding metalens 31 , which results in what can be called an out-of- focus image . For example , the array of optical filters 20 or the array of detector segments 10 are arranged behind the focal plane B in the propagating direction of the radiation R . Thus , the radiation R incident on the array of optical filters 20 or detector segments 10 is blurred . The ef fect of the out-of- focus image or blurring is described in connection with Figures 8A and 8B .

[0109] According to the exemplary embodiment of Figure 6 , the array of optical filters 20 or the array of detector segments 10 are arranged in the focal plane B of the array of metalenses 2024PF01291 November 24 , 2025

[0110] P2024 , 0933 WO N

[0111] - 19 -

[0112] 31 . In particular, every optical filter 20 or detector segment 10 is arranged in the focus of its corresponding metalens 31 , which results in what can be called an in- focus image . Thus , the radiation R incident on the array of optical filters 20 or detector segments 10 is not blurred . The ef fect of the in- focus image is described in connection with Figures 8A and 8B .

[0113] In the exemplary embodiment of Figure 7 , the telecentric optical means 30 comprise only one transparent substrate 32 , wherein the array of metalenses 31 is arranged on a side of the telecentric optical means 30 or transparent substrate 32 facing the composite including the semiconductor chip 1 and the array of optical filters 20 . The telecentric optical means 30 are directly arranged on the composite including the semiconductor chip 1 and the array of optical filters 20 , wherein the array of metalenses 31 may be in direct contact with the array of optical filters 20 . In this case , the array of optical filters 20 or detector segments 10 are arranged out of the focal plane , but before the focal plane in the propagating direction of the radiation R such that a simple blur of radiation exists .

[0114] In addition, the exemplary embodiments of Figures 5 to 7 may have all further features and advantages described in connection with the exemplary embodiment of Figure 1 .

[0115] As becomes evident from Figure 8A, the array of optical filters 20 or the array of detector segments 10 can be arranged in the focal plane B of the array of metalenses 31 such that the incident radiation R is focused in a plane of the array of optical filters 20 or the array of detector 2024PF01291 November 24 , 2025

[0116] P2024 , 0933 WO N

[0117] - 20 - segments 10 , resulting in highly concentrated radiation R without blurring .

[0118] Alternatively, as becomes evident from Figure 8B, the array of optical filters 20 or the array of detector segments 10 can be arranged out of the focal plane B of the array of metalenses 31 , for example behind the focal plane B in the propagating direction of the radiation R such that the incident radiation R is blurred in the plane of the array of optical filters 20 or the array of detector segments 10 . The blurred radiation may have at least approximately a Gaussian profile , which provides for reliable detectability .

[0119] The invention is not limited to these embodiments by the description based on the embodiments . Rather, the invention includes any new feature and any combination of features , which includes in particular any combination of features in the patent claims , even i f this feature or this combination itsel f is not explicitly explained in the patent claims or embodiments .

[0120] This patent application claims the priority of German patent application 102024138614 . 2 , the disclosure content of which is hereby incorporated by reference .

[0121] 2024PF01291 November 24, 2025

[0122] P2024, 0933 WO N

[0123] - 21 -

[0124] References

[0125] 1 semiconductor chip

[0126] 1A front surface

[0127] 10 detector segment

[0128] Ila, 11b, 11c, lid, lie, Ilf, 11g, llh, Hi detector subregion

[0129] 20 optical filter

[0130] 30 telecentric optical means

[0131] 30' multilens system

[0132] 31 metalens

[0133] 31A pattern element

[0134] 31A' , 31B' microlens array

[0135] 32 substrate

[0136] 33 aperture

[0137] 34 radiation-blocking layer

[0138] 40 carrier

[0139] 50 support

[0140] 100, 100' multi-spectral optical sensor

[0141] 200 electronic device dl, d2 diameter g gap

[0142] Al, A2, A3, A4, A5 wavelength

[0143] A optical axis 2024PF01291 November 24, 2025

[0144] P2024, 0933 WO N

[0145] - 22 -

[0146] B focal plane

[0147] C scene

[0148] Da, Db, De, Dd, De, Df, Dg, Dh, Di incidence direction

[0149] Sa, Sb, Sc, Sd, Se, Sf, Sg, Sh, Si sector R incident radiation

Claims

2024PF01291 November 24, 2025P2024, 0933 WO N- 23 -Claims1. A multi-spectral optical sensor (100) for detecting incident radiation (R) having a wavelength spectrum, wherein the multi-spectral optical sensor (100) comprises:- a semiconductor chip (1) comprising an array of detector segments (10) , wherein each of the detector segments (10) comprises an array of detector subregions (Ila, 11b, 11c, lid, lie, Ilf, 11g, llh, Hi) ,- an array of optical filters (20) , wherein each of the optical filters (20) is assigned to one of the detector segments (10) , and- telecentric optical means (30) comprising an array of metalenses (31) , wherein each of the metalenses (31) is assigned to one of the optical filters (20) and the array of optical filters (20) is arranged between the array of detector segments (10) and the array of metalenses (31) .

2. The multi-spectral optical sensor (100) according to the preceding claim, wherein the metalenses (31) in each case comprise a pattern of pattern elements (31A) , wherein the pattern elements (31A) have sizes smaller than wavelengths (Al, A2, A3, A4, A5) of the wavelength spectrum of the incident radiation (R) .

3. The multi-spectral optical sensor (100) according to the preceding claim, wherein each pattern changes a phase profile of the incident radiation (R) such that the incident radiation (R) is diffracted.

4. The multi-spectral optical sensor (100) according to any of the two preceding claims, wherein the pattern elements2024PF01291 November 24, 2025P2024, 0933 WO N245. The multi-spectral optical sensor (100) according to any of claims 2 to 4, wherein the patterns of the metalenses (31) are different.

6. The multi-spectral optical sensor (100) according to any of claims 2 to 5, wherein the metalenses (31) have a single layer or multilayer structure.

7. The multi-spectral optical sensor (100) according to any of claims 2 to 6, wherein the pattern elements (31A) comprise or consist of a material having a refractive index which is not matched to the refractive index of a surrounding material .

8. The multi-spectral optical sensor (100) according to any of the preceding claims, wherein the telecentric optical means (30) comprise at least one transparent substrate (32) and the array of metalenses (31) is arranged at a surface of the at least one transparent substrate (32) .

9. The multi-spectral optical sensor (100) according to any of the preceding claims, wherein the telecentric optical means (30) comprise two transparent substrates (32) and the array of metalenses (31) is arranged between the two transparent substrates (32) .

10. The multi-spectral optical sensor (100) according to any of the preceding claims, wherein the telecentric optical means (30) are directly arranged on the array of filters(20) .

11. The multi-spectral optical sensor (100) according to any of claims 1 to 9, wherein the multi-spectral optical sensor2024PF01291 November 24, 2025P2024, 0933 WO N25(100) comprises a support (50) and the telecentric optical means (30) are mounted on the support (50) .

12. The multi-spectral optical sensor (100) according to the preceding claim, wherein the optical filters (20) exhibit transmission spectra overlapping with absorption spectra of the detector subregions (Ila, 11b, 11c, lid, lie, Ilf, 11g, llh, Hi) of the assigned detector segments (10) .

13. The multi-spectral optical sensor (100) according to any of the preceding claims, wherein at least two of the optical filters (20) have different transmission spectra.

14. The multi-spectral optical sensor (100) according to any of the preceding claims, wherein each optical filter (20) comprises an interference filter.

15. The multi-spectral optical sensor (100) according to any of the preceding claims, which comprises diffusing means.

16. The multi-spectral optical sensor (100) according to any of the preceding claims, wherein the semiconductor chip (1) is a monolithic semiconductor chip and the optical filters (20) are arranged on a front surface (1A) of the semiconductor chip (1) .

Images