Functional sensor unit, camera system and method for light sensing

Abstract

Functional sensor unit (10), for use in a camera system (1), comprising an optical functional sensor (16) arranged in a chamber (14) with an aperture (18) in a housing (12), said optical functional sensor (16) arranged to detect received photons through said aperture (18), said optical functional sensor (16) comprising an array (36) of functional sensor pixels (38) arranged in said chamber (14), shall be improved in performance for use cases in which an associated camera is used in zoom mode. For this purpose, in accordance with the invention the aperture (18) of the functional sensor unit (10) is electrically adjustable.

Description

[0001] 2024PF01795 1

[0002] Functional Sensor Unit, Camera System and Method for Light Sensing

[0003] DESCRIPTION

[0004] Technical background of the invention

[0005] The invention relates to a functional sensor unit, in particular for use in a camera system. The invention in particular relates to a functional sensor unit comprising an optical functional sensor arranged in a chamber with an aperture in a housing, said optical functional sensor arranged to detect received photons through said aperture, wherein said optical functional sensor comprises an array of functional sensor pixels arranged in said chamber . The invention further relates to a camera system, and more particularly relates to a camera system comprising a camera sensor unit having an optical camera sensor, a functional sensor unit having an optical functional sensor, in particular an ambient light sensor, and a control unit . The invention furthermore relates to a method for light sensing.

[0006] Background

[0007] Optical sensors are increasingly being used in such diverse areas of technology as smart phones and mobile devices, smart homes and buildings, industrial automation, medical technology and connected vehicles, etc . At the same time, sensor data becomes more complex and is expected to meet the requirements for high accuracy. Further, color and spectral light sensing on a chip-scale have various applications in color identification, data authentication, spectroscopy, and other industrial and consumer-level optical detection applications . In a number of important applications, in particular for camera applications, such sensors, in particular in the form of, e . g. , ambient, color, and depth sensors, are often applied together with camera systems e . g. in a smart phone or weara-2024PF01795 2

[0008] ble devices in order to enhance or increase camera functions . In particular, such sensors are used as ambient light sensors ("ALS") for so-called "auto white balance" functionality, in order to provide essential background information for appropriate correction functionalities and thereby in general improve imaging quality.

[0009] Common multispectral sensors are often based on an array of pixels and on-pixel filters for each pixel . For spectroscopic applications the filters can be chosen to have linear independent filter characteristics . In order to accomplish an accurate spectral measurement of a given source, the angle of incidence (AOI ) of incoming radiation should be known in order to compensate for different response of individual filters . This way an amplitude of a spectral signal of a pixel can be used to calculate a spectral reconstruction of a light source or scenery under study. The results of such reconstruction are widely used to improve and optimize the sensor signals of an associated camera, thereby producing imaging results of superior quality.

[0010] In view of such applications, it is highly desirable to generate highly reliable, accurate readings in functional sensors of this type . Accordingly, it is a general goal to minimize or even eliminate all potential error sources in the context of the generation of such sensor signals . In this context, many problems resulting from specific illumination situations and the like, in particular resulting from dominant light sources and similar artifacts, have been solved. On this basis, in ambient light sensor systems, reliable relative measurement values between individual channels of the sensor may be obtained, independently of the direction or angle of incoming light or other sources due to illumination. Due to this reliable measurement of the respective spectral channel ratios, correct spectral reconstruction for proper characterization of incoming radiation will be possible .

[0011] Further, however, depending on the performance of the respective components, even on the basis of such highly reliable2024PF01795 3

[0012] sensor signals, it is desirable to further reduce other causes of data falsifications . In particular, the system accuracy may also depend on the particular details of the scene currently observed by the camera may be relevant for accurate evaluation of such functional sensors such as an ambient light sensor . One potential problem arising in this context may be the use of a zoom camera . In a zoom camera, among other aspects, the so-called "field of view" (FOV) of the camera sensor system is adjusted such that only a selected, targeted part of the scenery is detected and evaluated by the camera . While the camera uses an optical or digital zoom, focusing on only a part of the scenery and evaluating optical data from this selected part of the scenery only, however, the functional sensor (color sensor, als, etc . ) still detects light over the original, unfocused f ield-of-view of the sensor, independent of the camera zoom. Hence, the color correction for zoomed pictures may be subj ect to errors .

[0013] Further, an optical sensor with spatial resolution (e . g. 2D and 3D cameras) can suffer from artifacts due to uncontrolled reflections in the device (this is commonly called "ghosting") . In order to improve the quality of sensing in a targeted portion of the field of view it is desirable that such artifacts be blocked.

[0014] Summary

[0015] The obj ect of the invention is therefore to provide an improved functional sensor unit of the type identified above, that helps overcome the deficiencies identified above, in particular in use cases in combination with a zoom camera unit, in a particularly cost-saving manner . Further, an improved camera system comprising such a functional sensor unit should be provided, as well as an improved method for light sensing .

[0016] With respect to the functional sensor unit of the type identified above, this obj ect is achieved in that the aperture in2024PF01795 4

[0017] the housing in which the sensor pixels are arranged is designed as an electrically adjustable aperture .

[0018] Preferred embodiments are subj ect of the dependent claims .

[0019] The invention is based on the basic consideration that one cause of the deficiencies in the sensor performance described above may be seen in the aspect that for zoom cameras, the targeted or selected part of the scenery, and thus the field of view (FOV) of the camera, is adjustable, in contrast to typical functional sensors associated therewith. The resulting difference in FOV of the camera unit as compared to the FOV of the associated functional sensor is considered to lead to different effective "evaluation zones" of the scenery for the camera unit on the one hand side and the functional sensor on the other hand side . This deviation is considered a potential error contribution for sensor data . In order to overcome the potential deficiencies resulting therefrom, an adjustable FOV for the functional sensor should be provided, in order to allow for proper adjustment and possibly synchronized adjustment of the FOV of the functional sensor in accordance with the zoom-based adjustment of the camera sensor .

[0020] Thus, in summary, the invention suggests a concept for an optical sensor with an adaptable, in particular electronically adaptable, f ield-of-view (FOV) . The FOV of the sensor in one aspect of the invention can be adjusted to fit that of the zoom of the camera, such that the sensor obtains a signal in the same or a similar field of view as detected and evaluated by the camera .

[0021] In one aspect, the invention suggests a design for an optical functional sensor (color sensor, ALS, etc) that comprises a photodiode array combined with a material in the optical path that is able to guide light from adaptive FOVs onto the photodiodes of the functional sensor .

[0022] In one aspect and in a preferred embodiment, the FOV of the functional sensor can be electrically adjusted to fit that of2024PF01795 5

[0023] a camera that is associated with (and may be arranged next to) the functional sensor, in particular also when the FOV of the camera is changed, e . g. by zooming.

[0024] In a preferred embodiment, and within one aspect of the invention, the aperture is adjustable in the sense that its lateral size may be changed or adjusted, preferably such that the change in the FOV of the associated camera is matched. In a preferred embodiment, and taking into account that in typical zoom systems of cameras the FOV may be changed continuously over a certain range, the aperture in its lateral size is also adjustable continuously, preferably over a predefined range . Adjustment of the lateral size of the aperture, particularly of a tuneable aperture element of said aperture, preferably is possible in order to match a continuously variable input parameter, in particular and in one aspect of the present invention a parameter characteristic for the zooming mode of an associated camera .

[0025] In a preferred embodiment, this adaptive FOV can be achieved by providing an electrochromic material in the aperture associated with the sensor array. This electrochromic material in one aspect of the invention may be designed to change its opacity on top of the photodiodes, to adaptively block certain parts of the aperture area and thus of the image .

[0026] In yet another preferred embodiment a material may be provided in the aperture in which the directionality of transmissivity can be adjusted electronically, such as (polymer dispersed) liquid crystals that change their orientation under the influence of an electric field.

[0027] In a preferred embodiment, the optical functional sensor is an optical multispectral functional sensor . In one aspect, at least the functional sensor pixels each comprise a photodiode and a filter, wherein the filter determines the transmission characteristic of the respective sensor pixel .2024PF01795 6

[0028] In accordance with an aspect of the invention, the functional sensor unit with adjustable aperture may be combined with an optical camera sensor unit in order to provide an improved camera system, which is considered independently inventive . In one aspect of the invention, this improved camera system may comprise a control unit, wherein the control unit is arranged to adjust the FOV of the functional sensor unit in accordance with adjustments of the FOV of the camera sensor unit, e . g. by zooming the camera .

[0029] Accordingly, in this aspect the present invention suggests a camera system comprising a camera sensor, a functional sensor unit, in particular in accordance with the type identified above, and a control unit, wherein the optical camera sensor comprises an array of camera sensor pixels, each generating an irradiance sensor signal, and wherein the control unit is operable to adjust the aperture of said functional sensor unit in accordance with a change of field of view of said camera sensor .

[0030] In a preferred embodiment, the multispectral functional sensor unit is designed as an ambient light sensor .

[0031] With respect to the method for multispectral light sensing, the obj ect identified above in accordance with one aspect of the invention is achieved with the steps of :

[0032] - detecting received photons by means of an optical camera sensor,

[0033] wherein the optical camera sensor comprises an array of camera sensor pixels,

[0034] - for each camera sensor pixel, generating an irradiance sensor signal,

[0035] - detecting received photons by means of an optical multispectral functional sensor,

[0036] - adjusting an aperture provided in the optical path of the photons received by the optical multispectral functional sensor in accordance with a f ield-of-view of said optical camera sensor, and2024PF01795 7

[0037] - for each functional sensor pixel, generating a multispec-tral sensor signal .

[0038] In a preferred embodiment, the step of adjusting said aperture comprises changing the lateral size of an aperture element of said aperture .

[0039] In yet a further preferred embodiment, the method further comprises the step of providing the modified multispectral sensor signals as output signals of a functional sensor unit .

[0040] In one aspect of the invention, the method as defined above is used in an application for ambient light sensing, preferably in camera applications . In one aspect the present invention also suggests a camera system, preferably in a smartphone or a wearable device, comprising an ambient light sensor having an optical detector unit of the type identified above .

[0041] The major advantages achieved by the invention may be seen in that due to the basic concept of the invention of adjusting the aperture of a functional sensor unit such that the field-of-view of the functional sensor unit may be adjusted in accordance with possible changes of the f ield-of-view of an associated camera sensor, a proper match of the respective f ields-of-view may be maintained in various modes of operation of the camera . In particular, the functional sensor unit may be beneficial when used together with a zoom camera . In such use cases, the same number of detection zones may be evaluated at all zoom levels, e . g. for 16 x 9 = 144 sensing zones . Consequently, the functional sensor unit may use the same readout circuitry, conversion, and data processing at any zoom level . A single aperture may be provided even for systems for multiple imaging configurations; the system may be optimized for multiple zoom levels and multiple cameras in the end system, e . g. a smartphone with 3 or 4 cameras .2024PF01795 8

[0042] Brief Description of the Preferred Embodiments

[0043] Preferred embodiments and aspects of the invention are described further in connection with a drawing. In this drawing,

[0044] FIG. 1 shows a camera system, in particular for use in a smartphone, in cross section;

[0045] FIG. 2 shows a cross-sectional view of a functional sensor unit in various embodiments and modes of operation;

[0046] FIG. 3 shows a cross-sectional view of an alternative embodiment of a functional sensor unit in various embodiments and modes of operation; and

[0047] FIG. 4 shows an exemplary embodiment of an electrically adjustable aperture element .

[0048] Identical parts are labelled by the same reference numerals .

[0049] Detailed Description of the Preferred Embodiments

[0050] FIG. 1 shows an example of a camera system 1 in cross section that in the embodiment shown is integrated into a mobile device such as a smartphone . The camera system 1, as its major components, comprises the actual optical camera sensor unit 2 and an ambient light sensor 4 associated therewith. The camera sensor system 2 and the ambient light sensor 4 are mounted at the back of a common cover glass 6, which may be the cover glass 6 of the smartphone as such. The ambient light sensor 4 is used mainly for so-called "auto white balance" functionality in the camera system 1, in order to provide essential background information for appropriate correction functionalities and thereby in general improve imaging quality of the camera system 1.2024PF01795 9

[0051] The ambient light sensor 4 comprises a functional sensor unit 10 in the form and design of an optical sensor chip, in particular an optical multispectral sensor chip . It is noted that the concept proposed herein can be applied for various types of functional sensor chips and optical devices and that the present invention relates to the design of the camera system 1 alone and therefore, within the scope of the present invention, may very well be used with a functional sensor unit 4 in other applications as in ambient light sensors 4, e . g. in colour sensors .

[0052] The functional sensor unit 10 of the ambient light sensor 4 comprises a housing 12 with a sensor chamber 14 in which the actual optical multispectral functional sensor 16 is positioned. In order to allow for proper passage of light or radiation to reach the optical multispectral functional sensor 16 through the housing 12, the housing 12 is provided with an opening or aperture 18. For sake of illustration, the field of view of the camera sensor unit 2 and the field of view of the ambient light sensor 4 are also shown in FIG. 1, symbolized as cones 24, 26, respectively.

[0053] The housing 12 of the functional sensor unit 10 of the ambient light sensor 4 is arranged on a substrate or carrier 30. A cover section or lid 32 forming the aperture 18, and also part of the housing 12, is located opposite to the carrier 30 and thereby covers the chamber 14. The carrier or substrate 30 provides mechanical support and electrical connectivity to electronic components which are integrated into the functional sensor unit 10. For example, the carrier 30 may comprise a printed circuit board, PCB (not shown) . However, in other embodiments (not shown) the carrier 30 can also be part of the housing 12, and electronic components may be embedded into the housing 12 by moulding for example . In yet an alternative embodiment, the circuitry may be designed in TSV technology ("through silicon via") . A through-chip via is a vertical electrical connection (via) that passes completely through a silicon wafer or die . The contacting of the chip in this technology is brought to the backside of the chip and pro-2024PF01795 10

[0054] cessed as a BGA (ball grid array) . The advantage is that everything may be mounted at wafer level (Si, filter, glass, optic, aperture, diffuser . . . ) .

[0055] As part of the functional sensor unit 10, the optical multi-spectral functional sensor 16 is arranged inside the chamber 14 and on the carrier 30. In this particular embodiment, the optical sensor 16 is integrated into a single semiconductor sensor die 34 together with other electronics . The optical sensor comprises an array 36 of individual optical detector elements or pixels 38 which will be discussed in further detail below. The pixels 38 may be implemented as photodiodes, for example .

[0056] As further part of the functional sensor unit 10, an array 40 of optical filters 42 is arranged in the chamber 14 above the optical multispectral functional sensor 16. The array 40 of optical filters 42 is attached to the functional sensor 16. The pixels 38 each are associated with an associated optical filter 42 having a different transmission characteristic . Together the pixels 38 and associated filters 42 form a channel 44 of the functional sensor unit 10. The optical filters 42 determine the transmission characteristic of the respective sensor pixel 38 and the respective channel 44 ; they may be interference filters such as an optical cut-off filter, bandpass, long or short pass filter, dielectric filters, Fabry-Perot filters, polymer filters and / or hybrid filters .

[0057] In order to allow for proper passage of light or radiation, the cover or lid 32 of the housing 12 is provided with the aperture 18. The aperture 18 is positioned above the functional sensor 16. In fact, the aperture 18 lies within a field of view (FOV) of the optical sensor 16. The field of view of the optical sensor 16 includes all points in space from where, at least theoretically, light radiated from an external radiation or light source may traverse towards the optical sensor 16, e . g. for a fixed detector position and orientation .2024PF01795 11

[0058] A control unit and / or a measurement unit (not shown) may be integrated into the semiconductor sensor die 34 alongside with the optical functional sensor 16. The measurement unit can be considered a control unit for the optical functional sensor unit 10. For example, it may provide sensor signals which are generated by the optical functional sensor 16. The control unit and / or the measurement unit may be implemented as control logic, state machines, microprocessor and the like . They may also comprise additional components such as analog-to-digital converters, time-to-digital converters, amplifiers which too are located in the semiconductor sensor die 34. The semiconductor die 34 may have a printed circuit board PCB providing electrical communication to the individual components of the multispectral sensor . In operation, incoming radiation can be detected entering through the aperture 18 by means of the multispectral sensor 16. Each sensor pixel 38 in reaction generates a multispectral sensor signal, respectively. The measurement unit therefore in total provides a set of multispectral sensor signals .

[0059] As also shown in FIG. 1, in simplified form in order to explain the basic concept of the present invention, the camera sensor unit 2 also may be designed in the general form of a sensor chip . The camera sensor unit 2 comprises a housing 50 with a sensor chamber 52 in which the optical camera sensor 54 is positioned. On top of the camera sensor 54, and in the direction towards incoming light, an optical system is provided, symbolized in FIG. 1 by lens 56.

[0060] The housing 50 of the camera sensor unit 2 is arranged on a substrate or carrier 58. The carrier or substrate 58 provides mechanical support and electrical connectivity to electronic components which are integrated into the camera sensor unit 2. For example, the carrier 58 may comprise a printed circuit board, PCB (not shown) . However, in other embodiments (not shown) the carrier 58 can also be part of the housing 50, and electronic components may be embedded into the housing 50 by molding for example . In yet an alternative embodiment, the circuitry may be designed in TSV technology ("through silicon2024PF01795 12

[0061] via") . A through-chip via is a vertical electrical connection (via) that passes completely through a silicon wafer or die . The contacting of the chip in this technology is brought to the backside of the chip and processed as a BGA (ball grid array) . The advantage is that everything may be mounted at wafer level (Si, filter, glass, optic, aperture, diffuser

[0062] As part of the camera sensor unit 2, the optical camera sensor 54 is arranged inside the chamber 52 and on the carrier 58. In this particular embodiment, the camera sensor 54 is integrated into a single semiconductor sensor die 60 together with other electronics . The optical camera sensor 54 comprises an array 62 of individual camera sensor pixels 64. In other words, the digital camera unit 2 comprises an array 62 of sensors .

[0063] Further, the optical camera sensor unit 2, in addition to the optical camera sensor 54, comprises a control unit 70, which with respect to data transfer and communication is connected with the optical camera sensor 54 and / or its control system if applicable, as symbolized by double arrow 72. In the embodiment shown, the control unit 70 further with respect to data transfer and communication is connected with the optical multispectral functional sensor 16 and / or its control system if applicable, as indicated by double arrow 74. It is noted that in the embodiment shown, control unit 70 is provided as a separate component, but of course it may as well be integrated with the control system of the camera sensor 54 and / or the control system of the multispectral sensor 16. In consequence, in one aspect of the invention and in the embodiment shown, the camera system 1 comprises the camera sensor unit 2, the functional sensor unit 10 featuring the ambient light sensor 4, and the control unit 70.

[0064] In the embodiment shown, the optical camera sensor unit 2 is designed as a zoom camera, in the sense that the lens 56 and the optical system associated therewith may be adjusted or manipulated by the user such that - depending on the settings2024PF01795 13

[0065] provided by the user - different, selected target segments of the total scenery are delivered to the array 62 of camera pixels 64. In accordance with this user-modified selection of segments of the scenery, the effective f ield-of-view of the camera sensor unit 2 as represented by cone 24 may be modified by the user .

[0066] This zoom function of the camera sensor unit 2, however, may have a disadvantageous impact on the performance of the ambient light sensor 4. In particular, as a consequence of the zoom function, the camera sensor unit 2 will focus on a part of the scenery only, and will evaluate optical data from this selected part of the scenery only. In contrast, without further action, the functional sensor unit 10 provided as ambient light sensor 4 will still provide sensor data for the original, unfocused f ield-of-view of the sensor unit 2, independently of the camera zoom. Hence, the colour correction provided for zoomed pictures may be subj ect to errors .

[0067] In order to compensate for this and to improve the performance and measurement quality of the functional sensor unit 10 even when used together with a zoom camera as shown for the camera sensor unit 2, the functional sensor unit 10 in accordance with one aspect of the invention is provided with an electrically adjustable aperture 18. For this purpose, in the embodiment shown, the aperture 18 comprises a tuneable or electrically adjustable aperture element 80 provided in the optical path of the optical multispectral sensor 16.

[0068] In the embodiment shown, and in one aspect of the invention, accordingly the photodiode array 36 of the optical multispectral sensor 16 is combined with the aperture element 80 provided in the optical path of the sensor array 36. In this setup, the functional sensor unit 10 is able to guide light from adaptive FOVs onto the pixels 38 of the functional sensor unit 10. The FOV of the functional sensor unit 10 can then be electrically adjusted to fit that of the camera sensor unit 2 even when the FOV of the camera is changed, e . g. by zooming. In order to allow for this electrical tuning of2024PF01795 14

[0069] the aperture element 80, it comprises a material that changes opacity, which is controlled by control signals from control unit 70. For this purpose, the tuneable aperture element 80 with respect to data transfer and communication is connected with the control unit 70, as symbolized by double arrow 82.

[0070] In one embodiment, as shown in enlarged cross-sectional view of the functional sensor unit 10 in various embodiments and modes of operation in FIG. 2, the tuneable aperture element 80 may comprise a block 84 of orientable liquid crystal material, in particular polymer-dispersed liquid crystal . In the embodiment shown in FIG. 2, block 84 on its top and bottom sides 86, 88 is provided with electrodes 90, 92. Application of an electric voltage between electrodes 90, 92, and thus across block 84, may then initiate reorientation of the liquid crystals in block 84, thereby locally changing its opacity in those areas in which the voltage is applied. In order to selectively change the opacity in certain areas of the block 84, thereby effectively modifying the virtual aperture of the system, the electrodes 90 and / or 92 may be provided in segmented design, one or each comprising a number of segments that may be activated independently of other segments .

[0071] In FIG. 2a, the functional sensor unit 10 is shown in an "embedded design", i . e . in a design without separate housing 12, in an operational mode with "fully opened" tuneable aperture element 80. In this mode, the "effective" Field-of-view as represented by cone 94 is close to the maximum available field-of-view, as represented by cone 26. In contrast, FIG. 2b shows the functional sensor unit 10 in an operational mode with "closed" tuneable aperture element 80. Evidently, in this mode, the effective field-of-view as represented by cone 96 is significantly smaller than in "fully opened" mode of FIG. 2a .

[0072] In FIGs . 2c, 2d, the functional sensor unit 10 is shown in the design of FIG. 1, in which the tuneable aperture element 80 is mounted within housing 12. Again, in FIG. 2c, the functional sensor unit 10 is shown in an operational mode with2024PF01795 15

[0073] "fully opened" tuneable aperture element 80. In this mode, the "effective" Field-of-view as represented by cone 94 is close to the maximum available field-of-view, as represented by cone 26. In contrast, FIG. 2d shows the functional sensor unit 10 in an operational mode with "closed" tuneable aperture element 80. Evidently, in this mode, the effective field-of-view as represented by cone 96 is significantly smaller than in "fully opened" mode of FIG. 2c .

[0074] Similarly, in another embodiment, as shown in enlarged cross-sectional view of the functional sensor unit 10 in various embodiments and modes of operation in FIG. 3, the tuneable aperture element 80 ' may comprise a block 84 ' of electro-chromic material with tuneable opacity, with an internal structure shown in FIG. 4. In the embodiment shown in FIG. 3, application of an electric voltage across block 84 ' , will result in local change of its opacity.

[0075] In FIG. 3a, the functional sensor unit 10 is shown in an "embedded design", i . e . in a design without separate housing 12, in an operational mode with "fully opened" tuneable aperture element 80" . In this mode, the "effective" Field-of-view as represented by cone 94 is close to the maximum available field-of-view, as represented by cone 26. In contrast, FIG. 3b shows the functional sensor unit 10 in an operational mode with "closed" tuneable aperture element 80. Evidently, in this mode, the effective field-of-view as represented by cone 96 is significantly smaller than in "fully opened" mode of FIG. 3a .

[0076] In FIGs . 3c, 3d, the functional sensor unit 10 again is shown in the design of FIG. 1, in which the tuneable aperture element 80 is mounted within housing 12. Again, in FIG. 3c, the functional sensor unit 10 is shown in an operational mode with "fully opened" tuneable aperture element 80. In this mode, the "effective" Field-of-view as represented by cone 94 is close to the maximum available field-of-view, as represented by cone 26. In contrast, FIG. 3d shows the functional sensor unit 10 in an operational mode with "closed" tuneable2024PF01795 16

[0077] aperture element 80. Evidently, in this mode, the effective f ield-of-view as represented by cone 96 is significantly smaller than in "fully opened" mode of FIG. 3c .

[0078] In FIG. 4, the structure of electrochromic block 84 ' is shown schematically. The electrochromic block 84 ' , as mentioned, is configured to change its optical properties when a voltage is applied to the material . For example, the transmission for electromagnetic radiation is changed when a voltage is applied to the electrochromic block 84 ' . For this purpose, block 84 ' may comprise an active layer 100, also referred to as working electrode 100, of an electrochromic material such tungsten oxide (WO3) . It is further possible that the electrochromic material in layer 100 comprises an organic polymer .

[0079] On the active layer 100 or working electrode 100, an ion conducting layer 102 can be arranged. The ion conducting layer 102 may, for example, comprise Ta2Os . On top of the ion conducting layer 102, in turn, a counter electrode 106 and / or a charge storage layer 108 may be provided. The charge storage layer 108 can comprise NiO. This stack of layers 100 - 108 on both sides then, for contacting purposes, may be provided with transparent conductor layers 110, made, for example, from nickel, chromium or a transparent conductive oxide such as indium tin oxide ( ITO) .

[0080] This stack of layers forming the electrochromic block 84 ' , in particular the electrochromic material, can be deposited by conventional thin film technologies such as sputtering or by evaporation. The conductor layers 110, in their function as contacting elements, may be segmented or designed in the form of a grid comprising an electrically conductive material .

[0081] In operation of the camera system 1, the method for light sensing comprises, among others, the steps of detecting received photons by means of the optical functional sensor 16, and adjusting the aperture 18 provided in the optical path of the photons received by the optical functional sensor 16 in2024PF01795 17

[0082] accordance with a set f ield-of-view of the optical camera sensor 54, which potentially might be changed by zooming the camera .

[0083] The embodiments of the camera system 1 discussed herein have been disclosed for the purpose of familiarizing the reader with novel aspects of the idea . Although preferred embodiments have been shown and described, many changes, modifications, equivalents and substitutions of the disclosed concepts may be made by one having skill in the art without unnecessarily departing from the scope of the claims .

[0084] In particular, the disclosure is not limited to the disclosed embodiments, and gives examples of as many alternatives as possible for the features included in the embodiments discussed. However, it is intended that any modifications, equivalents and substitutions of the disclosed concepts be included within the scope of the claims which are appended hereto .

[0085] Features recited in separate dependent claims may be advantageously combined. Moreover, reference signs used in the claims are not limited to be construed as limiting the scope of the claims .

[0086] Furthermore, as used herein, the term "comprising" does not exclude other elements . In addition, as used herein, the article "a" is intended to include one or more than one component or element, and is not limited to be construed as meaning only one .

[0087] Unless otherwise expressly stated, it is in no way intended that any method set forth herein be construed as requiring that its steps be performed in a specific order . Accordingly, where a method claim does not actually recite an order to be followed by its steps or it is not otherwise specifically stated in the claims or descriptions that the steps are to be limited to a specific order, it is in no way intended that any particular order be inferred.2024PF01795 18

[0088] LIST OF REFERENCE NUMERALS

[0089] 1 camera system

[0090] 2 camera sensor unit

[0091] 4 ambient light sensor

[0092] 6 cover glass

[0093] 10 functional sensor unit

[0094] 12 housing

[0095] 14 chamber

[0096] 16 optical functional sensor

[0097] 18 aperture

[0098] 24, 26 cone

[0099] 28 radiation pattern

[0100] 30 substrate

[0101] 32 lid

[0102] 34 sensor die

[0103] 36 array

[0104] 38 pixel

[0105] 40 array

[0106] 42 optical filter

[0107] 44 channel

[0108] 50 Housing

[0109] 52 sensor chamber

[0110] 54 optical camera sensor

[0111] 56 lens

[0112] 58 substrate

[0113] 60 sensor die

[0114] 62 array

[0115] 64 camera sensor pixel

[0116] 70 control unit

[0117] 72, 74 double arrow

[0118] 80, 80 ' aperture element

[0119] 82 double arrow

[0120] 84 , 84 ' block

[0121] 86, 88 top, bottom side of block 84

[0122] 90, 92 Electrode

[0123] 94, 96 cone

[0124] 100 - 108 layer2024PF01795 - 19 -

[0125] 110 conductor layer

Claims

2024PF01795 20CLAIMS1 . Functional sensor unit ( 10 ) comprising an optical functional sensor ( 16 ) arranged in a chamber ( 14 ) with an aperture ( 18 ) in a housing ( 12 ) , said optical functional sensor ( 16 ) arranged to detect received photons through said aperture ( 18 ) , said optical functional sensor ( 16 ) comprising an array ( 36 ) of functional sensor pixels ( 38 ) arranged in said chamber ( 14 ) , wherein said aperture ( 18 ) is electrically adj ustable .2 . The functional sensor unit ( 10 ) of claim 1 , wherein said aperture ( 18 ) is adj ustable in its lateral si ze .3 . The functional sensor unit ( 10 ) of claim 1 or 2 , wherein said aperture ( 18 ) comprises a tuneable aperture element ( 80 ) .4 . The functional sensor unit ( 10 ) of claim 3 , wherein said tuneable aperture element ( 80 ) is continuously tuneable in order to match a continuously variable input parameter .

5. The functional sensor unit ( 10 ) of claim 3 or 4 , wherein said tuneable aperture element ( 80 ) comprises electro- chromic material .

6. The functional sensor unit ( 10 ) of any one of claims 1 to 5 , wherein said optical functional sensor ( 16 ) is an optical multispectral functional sensor ( 16 ) , wherein the functional sensor pixels ( 38 ) each have a di f ferent spectral transmission characteristic, each generating a multispectral sensor signal , respectively .7 . The functional sensor unit ( 10 ) of any one of claims 1 to 6 , wherein at least the functional sensor pixels ( 38 ) each comprise a photodiode and a filter ( 42 ) , wherein the2024PF01795 21filter ( 42 ) determines the transmission characteristic of the respective sensor pixel ( 38 ) .8 . Camera system ( 1 ) comprising a camera sensor unit ( 2 ) having an optical camera sensor ( 54 ) , a functional sensor unit ( 10 ) in accordance with any one of claim 1 to 7 , and a control unit ( 70 ) , wherein the optical camera sensor ( 54 ) comprises an array ( 62 ) of camera sensor pixels ( 64 ) , each generating an irradiance sensor signal , and wherein the control unit ( 70 ) is operable to adj ust the aperture ( 18 ) of said functional sensor unit ( 10 ) in accordance with a change of field of view of said camera sensor ( 54 ) .

9. The camera system ( 1 ) of claim 8 , in which the functional sensor unit ( 10 ) is designed as an Ambient Light Sensor ( 4 ) .10 . Method for light sensing, comprising the steps of :- detecting received photons by means of an optical camera sensor ( 54 ) ,wherein the optical camera sensor ( 54 ) comprises an array ( 62 ) of camera sensor pixels ( 64 ) ,- for each camera sensor pixel ( 64 ) , generating an irradiance sensor signal ,- detecting received photons by means of an optical functional sensor ( 16 ) ,- adj usting an aperture ( 18 ) provided in the optical path of the photons received by the optical functional sensor ( 16 ) in accordance with a f ield-of-view of said optical camera sensor ( 54 ) , and- for each functional sensor pixel ( 38 ) , generating a sensor signal .11 . The method for light sensing of claim 10 , wherein the step of adj usting said aperture comprises changing the lateral si ze of an aperture element ( 80 ) of said aperture2024PF01795 2212. The method of claim 11, further comprising the step of providing the sensor signals as output signals of a functional sensor unit ( 10) .

13. Use of the method of any one of claims 10 to 12 in an application for ambient light sensing, preferably in camera applications .

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