Optical detector, image recording device and manufacturing method

Abstract

In one embodiment, the optical detector (1) includes: - an aperture plate (3) including a first layer (31) and a second layer (32); - a plurality of first sensors (21) located at the second layer (32); and a second sensor (22) also located at the second layer (32), wherein, - for each of the first sensors (21), a first aperture (41) and a second aperture (42) are respectively present in the first layer (31) and the second layer (32), such that for each of the first sensors (21), there is an aperture stack (44) defining the sensitivity direction (C) of the corresponding first sensor in the first sensor (21), and - the second sensor (22) has a line of sight (S) through at least one of the first apertures (41).

Description

Technical Field

[0001] An optical detector and an image recording apparatus including such an optical detector are provided. A method for manufacturing such an optical detector is also provided. Background Technology

[0002] Document WO 2023 / 006631 A1 relates to a segmented multispectral sensor with optical ambiguity.

[0003] The problem to be solved is to provide an optical detector with a reduced size. Summary of the Invention

[0004] This objective is achieved, in particular, by the optical detector, image recording apparatus, and manufacturing method defined in the independent claims. Exemplary further improvements constitute the subject matter of the dependent claims.

[0005] For example, the optical setup described herein is used for flicker detection in multi-aperture compound eye sensors used in smartphones.

[0006] According to at least one embodiment, the optical detector includes an aperture plate. The aperture plate has a first layer and a second layer. For example, the first and second layers are made of an opaque material or a sequence of opaque layers. That is, the first and second layers are opaque at the locations where the opaque material or the sequence of opaque layers is present.

[0007] According to at least one embodiment, the first layer and the second layer each include a plurality of first apertures and a plurality of second apertures. For example, the first apertures and the second apertures are holes in the opaque material or opaque layer sequence of the first and second layers. Therefore, light can travel through the first apertures and the second apertures.

[0008] According to at least one embodiment, the optical detector includes one or more first sensors. The first sensors are photosensitizing and, for example, photodiodes. Each of the first sensors may be a single-channel photodetector. The first sensors may be silicon-based.

[0009] According to at least one embodiment, the optical detector includes one or more second sensors. At least one second sensor is photosensitized and, for example, a photodiode. At least one second sensor may be a single-channel photodetector. At least one second sensor may also be silicon-based.

[0010] According to at least one embodiment, for each of the first sensors, at least one first aperture and at least one second aperture are respectively present in the first layer and the second layer. In particular, each first sensor has exactly one first aperture and one second aperture.

[0011] According to at least one embodiment, for each of the first sensors, an assigned first aperture and an assigned second aperture define an aperture stack. The aperture stack determines the sensitivity direction of a corresponding first sensor. Therefore, the aperture stack can be similarly considered as a tube or cone pointing along the sensitivity direction, and light can pass through this tube or cone to reach the corresponding first sensor.

[0012] According to at least one embodiment, the second sensor has a line of sight through one or more first apertures. That is, light can reach the second sensor through at least one first aperture (e.g., specifically through at least one first aperture).

[0013] In at least one embodiment, the optical detector includes: - Aperture plate, comprising a first layer and a second layer, - Multiple first sensors, located in the second layer, and - The second sensor, which is also located on the second layer, wherein... - For each of the first sensors, a first aperture and a second aperture exist in the first layer and the second layer, respectively, such that for each of the first sensors, there exists an aperture stack that defines the sensitivity direction of the corresponding first sensor. - The second sensor has a line of sight through at least one of the first apertures; Optionally, the second sensor has a light incident surface and a line of sight through at least one of the first apertures, and a line of sight perpendicular to the light incident surface.

[0014] The optical detectors described herein can be used for ambient light sensing and white balance, particularly flicker detection. These optical detectors can be used, for example, in portable devices such as smartphones, cameras, or camcorders.

[0015] The second sensor can be particularly effectively used in optical detectors with sectored color sensitivity of spectral sensors based on compound eye optics made of multiple apertures.

[0016] The accuracy of color and spectral measurements depends particularly on the integration of the synchronization signal over the source frequency. Therefore, a second sensor is integrated as an additional detector to detect the flicker frequency of at least one scene source. Due to sector overlap and blurring in the optical path, segmented information about source flicker is not relevant in all cases. It is meaningful that flicker conditions for all segments simultaneously set all measurement channels of the spectral detector (i.e., the second sensor) to the same integration time.

[0017] The size and cost of a multi-sector color and spectral sensor configuration depend primarily on the number of segmented sectors and the number of colors, i.e., the number of spectral channels. For example, if there is space for twelve spectral channels, each with nine orientations, then to improve performance, it is best to use all available channels as spectral channels rather than dedicating one channel to scintillation detection. Therefore, an optical setup capable of collecting light from all sectors is required. Since only temporal information for scintillation analysis is being analyzed, precise angular power distribution is not as critical.

[0018] The optical detector described in this paper utilizes the parasitic crosstalk effect to achieve overall flicker detection, which, for example, covers the entire scene within the field of view (FOV) without increasing the size and cost of the device.

[0019] Due to the refractive index of the glass or other carriers of the aperture sheet, the maximum possible detection angle is limited to approximately 40°. The aperture regions of the middle and bottom aperture layers between the first sensor arrays of the spectral channels have no optical relevance for spectrally sensitive compound eye detection. For example, this region can be used to detect crosstalk signals using only an additional, unfiltered second sensor. Therefore, an additional detector without filters (i.e., the second sensor) can collect light passing through the corner apertures of the upper first layer of the aperture sheet. In an optimized aperture layer design, this can cover and overlap the entire segmental FOV of all segments of the color channels using only a single second sensor.

[0020] By employing such an optical detector, costs can be saved, and the device size does not need to be increased because the system does not require additional area for scintillation detection. All optical channels can be used to improve spectral performance. Complete coverage and overlap of the scene's field of view (FOV) can be achieved using a single detector. For example, only one modulator is needed for scintillation processing. Previously unused aperture regions between parasitic effects and spectral channels can be used for scintillation detection.

[0021] Therefore, the optical detector described in this paper can be used as an ambient light sensor, or ALS for short.

[0022] According to at least one embodiment, each first sensor has exactly one aperture stack. Therefore, there can be a one-to-one correspondence between the first sensors and the aperture stacks.

[0023] According to at least one embodiment, a color filter is provided for each of the first sensors. Multiple color filters may be present. The first sensors may be arranged in groups or arrays, and each of the first sensors in a corresponding group or array is assigned the same color filter. Therefore, each group or array can be sensitive within the same spectral range, which is, for example, a subrange of the visible spectral range. For example, the visible spectral range is from 400 nm to 780 nm.

[0024] According to at least one embodiment, each of the first sensors is sensitive only within a sub-range of the visible spectral range. For example, there may be at least three or at least five sub-ranges, and / or at most 36, 20, or 12 sub-ranges. The sub-ranges may be paired distinctly and / or may be non-overlapping such that they do not overlap. Otherwise, at least some adjacent sub-ranges may overlap spectrally. The sub-ranges, or some of them, may be adjusted to configure the optical detector for the spectral sensitivity range of an image recording device configured therein or incorporated therein.

[0025] According to at least one embodiment, the second sensor is sensitive across the entire visible spectrum and / or across the entire spectral sensitivity range of the associated camera system. Therefore, unlike the first sensor, the second sensor may not exhibit any significant spectral selectivity within the visible spectrum.

[0026] According to at least one embodiment, the second sensor is configured to generate a time-dependent flicker signal. That is, the second sensor is configured to record a time-dependent intensity signal. For example, the sampling rate of the second sensor is at least 1 kHz, or at least 0.1 MHz, or at least 1 MHz, or at least 10 MHz. Thus, for example, the second sensor can detect 50 Hz or 100 Hz flicker, or 60 Hz or 120 Hz flicker of artificial light sources (such as light bulbs or fluorescent lamps), or it can also detect kHz or MHz flicker of artificial light sources such as light-emitting diodes (LEDs) driven by pulse width modulation (PWM).

[0027] According to at least one embodiment, the optical detector further includes one or more detection timers. At least one detection timer is configured to synchronize the detection time interval of the first sensor with the flicker signal. That is, for example, if a 50 Hz flicker is detected by means of a second sensor, the detection time intervals of all the first sensors are set to be a multiple of the flicker period. In other words, for the detection time interval Td, the flicker frequency f, and a natural number n greater than or equal to one, the formula Td = n / f can be applied. If multiple flicker frequencies exist, the lowest flicker frequency can be selected for the above formula, or n can be selected such that Td is an integer multiple of all or some of the flicker frequencies. For example, this can be applied to uncertainties of at most 1 ms, at most 0.1 ms, or at most 0.01 ms.

[0028] According to at least one embodiment, the first layer does not have an aperture specifically for the second sensor and is not part of at least one aperture stack in the aperture stack. Therefore, the second sensor can have a line of sight specifically through at least one of the first apertures. In other words, with respect to the first layer, the second sensor can specifically use one or more first apertures.

[0029] According to at least one embodiment, the second layer includes a scintillation aperture. The scintillation aperture can be specifically assigned to a second sensor. If multiple scintillation apertures and second sensors exist, a one-to-one correspondence can exist between the scintillation apertures and the second sensors.

[0030] According to at least one embodiment, viewed from a top view of the light incident surface, the scintillation aperture partially covers the light incident surface of the assigned second sensor. For example, viewed from a top view, the scintillation aperture is completely surrounded by a portion of the light incident surface. That is, viewed from a top view, the scintillation aperture may be entirely located within the light incident surface.

[0031] For example, the light incident surface is the light-sensitive portion of the main side surface of the second sensor. Therefore, light arriving at the light incident surface is purposefully converted into an electrical signal. This main side surface may have an edge region surrounding the light incident surface that is insensitive to incident light; therefore, light arriving at the edge region will not generate an electrical signal.

[0032] According to at least one embodiment, viewed from a top view of the light incident surface, the light incident surface of the second sensor partially overlaps with at least one of the first apertures defining the line of sight of the second sensor. In other words, the light incident surface is partially devoid of opaque material or a sequence of opaque layers forming the first layer of the aperture sheet. Therefore, a line of sight perpendicular to the light incident surface can exist. The light incident surface may be parallel to the first layer and / or the second layer.

[0033] According to at least one embodiment, the aperture sheet includes one or more intermediate layers. At least one intermediate layer is located between the first layer and the second layer. For example, at least one intermediate layer is also made of an opaque material or a sequence of opaque layers that forms the first layer of the aperture sheet.

[0034] According to at least one embodiment, the intermediate layer or each of the intermediate layers includes an intermediate aperture that is specifically assigned to one of the aperture stacks. That is, for each of the aperture stacks, an intermediate aperture may be present in each of the intermediate layers.

[0035] According to at least one embodiment, each of the intermediate layers includes an additional scintillation aperture specifically allocated to the second sensor. That is, the additional scintillation aperture is not part of any of the aperture stacks, but is separate from the aperture stacks.

[0036] According to at least one embodiment, the additional scintillation aperture of the intermediate layer and the scintillation aperture of the second layer are equal, or the scintillation aperture is larger than the additional scintillation aperture. The term "larger" may refer to the area content of the corresponding aperture.

[0037] According to at least one implementation, there is exactly one intermediate layer. Alternatively, there are multiple intermediate layers, such as two or three intermediate layers.

[0038] According to at least one embodiment, each of the aperture stacks widens in a direction away from the second layer. That is, the aperture becomes larger along the sensitivity direction and away from the second layer (i.e. towards the first layer).

[0039] According to at least one embodiment, the first sensor is arranged in multiple arrays. For example, each of the arrays is sensitive to a specific color and includes multiple first sensors. That is, each of the arrays may correspond to a color channel sensitive to a corresponding subrange of the visible spectrum.

[0040] According to at least one embodiment, the number of first sensors in each of the arrays is the same as the number of sensitivity directions in the corresponding array. That is, for example, each of the first sensors in the corresponding array is sensitive within the same spectral range, but the first sensors are used for different sensitivity directions. Within each array, no two sensitivity directions may be identical.

[0041] All arrays can have the same set of sensitivity directions. That is, in terms of sensitivity direction, all arrays can be the same, but the arrays have different sub-ranges of sensitivity.

[0042] According to at least one embodiment, viewed from the top view of the second layer, the distance between adjacent first sensors within the array is less than the distance between adjacent arrays within the array. In other words, the distance between the first sensors is closer to each other than the distance between the arrays.

[0043] According to at least one embodiment, the second sensor is located between the arrays. For example, the distance between the arrays is chosen to be a minimum distance, i.e., a distance such that the first apertures of adjacent first sensors in different arrays do not touch. Therefore, there are still some opaque material or opaque layer sequences forming the first layer between these first apertures. For example, the distance between the first apertures is at least 30 μm or at least 90 μm. Alternatively or additionally, this distance is at most 0.5 mm or at most 0.2 mm.

[0044] According to at least one embodiment, the number of first sensors in each of the arrays is at least four or at least nine. Alternatively or additionally, the number is at most 36, at most 25, or at most 16.

[0045] According to at least one embodiment, the optical detector includes a plurality of second sensors. For example, there may be up to ten or up to five second sensors. The term "plurality of second sensors" may refer to a single second sensor or a segmented second sensor having electrically individually readable segments.

[0046] According to at least one embodiment, some or all of the second sensors have paired, different sensitivity orientations. Therefore, with respect to flicker detection, multiple sensitivity orientations can exist.

[0047] According to at least one embodiment, the aperture sheet comprises a continuous, non-porous substrate. For example, a first layer and a second layer are applied to the main side surface of the substrate. For example, the substrate is a glass sheet or a plastic sheet.

[0048] If at least one intermediate layer is present, the matrix can be a laminate of sub-sheets, with the intermediate layer applied between the sub-sheets. Therefore, the intermediate layer can be located within the matrix.

[0049] According to at least one embodiment, the matrix has a refractive index of at least 1.4 or at least 1.5 and / or at most 1.8 or at most 1.7. For example, this applies to a wavelength of 532 nm and a temperature of 300 K.

[0050] For example, the total thickness of the substrate is at least 0.2 mm and / or at most 2 mm or at most 1 mm. For example, the thickness of the sub-sheet is at least 50 μm or at least 150 μm and / or at most 450 μm or at most 320 μm.

[0051] Another image recording apparatus is provided. The image recording apparatus includes an optical detector as indicated in conjunction with at least one of the above embodiments. Therefore, the features of the image recording apparatus are also disclosed with respect to the optical detector, and vice versa.

[0052] In at least one embodiment, the image recording device includes one or more optical detectors.

[0053] Furthermore, the image recording apparatus includes one or more camera systems, at least one of which is configured to capture images, such as photographs and / or videos, within the visible spectrum. Additionally, the image recording apparatus includes one or more processing units. At least one processing unit is configured to calculate the white balance of the image captured by the camera system using data from at least one optical detector.

[0054] Another method for manufacturing an optical detector is provided. By means of this method, an optical detector module as indicated in combination with at least one of the above embodiments is produced. Therefore, features of the optical detector and the image recording apparatus are also disclosed with respect to this method, and vice versa.

[0055] In at least one embodiment, the manufacturing method for producing an optical detector includes the following steps: A) Provide a substrate for supporting the first sensor and the second sensor. B) Provide an aperture sheet having a first layer and a second layer, and C) Attach the aperture plate to the substrate.

[0056] Step C) is executed after steps A) and B). Steps A) and B) may be executed in the order described, in reverse order, or simultaneously. Attached Figure Description

[0057] The optical detector, image recording apparatus, and manufacturing method described herein will now be explained in more detail with reference to the accompanying drawings and exemplary embodiments. Identical elements in the various drawings are indicated by the same reference numerals. However, the relationships between elements are not shown to scale; rather, individual elements may be exaggerated for ease of understanding.

[0058] In the attached diagram: Figure 1 This is a schematic top view of an example embodiment of an image recording apparatus having the optical detector described herein. Figure 2 yes Figure 1 A schematic partial cross-sectional view of an image recording device. Figure 3 yes Figure 1 and Figure 2 A schematic representation of the optical characteristics of an image recording device. Figure 4 This is a schematic top view of the modified optical detector. Figure 5 yes Figure 4 A schematic cross-sectional view of the modified optical detector. Figure 6 This is a schematic top view of an example implementation of the optical detector described herein. Figure 7 yes Figure 6 A schematic cross-sectional view of the optical detector. Figure 8 This is a schematic cross-sectional view of an example implementation of the optical detector described herein. Figure 9 This is a schematic top view of an example implementation of the optical detector described herein, and Figure 10 This is a schematic block diagram of an example implementation of the method for manufacturing an optical detector described herein. Detailed Implementation

[0059] Figure 1 and Figure 2 An embodiment of the image recording device 10 is shown. For example, the image recording device 10 is a smartphone. The image recording device 10 includes a camera system 11 and an optical detector 1. For example, the camera system 11 and the optical detector 1 may be located below the cover glass 13. In addition, the image recording device 10 includes a processing unit 12.

[0060] Camera system 11 has a field of view (FOV) around an observation direction P, which may be an optical axis. Note that camera system 11 is shown only schematically, and therefore components of camera system 11 (such as lenses, optical filters, CCD chips, or electronics) are not shown. For example, camera system 11 is configured to capture images and record video.

[0061] The optical detector 1 is a multispectral detector, meaning that it is sensitive in several sub-ranges of the visible spectrum. Therefore, the optical detector 1 can be an ambient light sensor (ALS) used for white balancing the camera system 11.

[0062] Furthermore, the optical detector 1 has a detection field of view (FOD) surrounding the observation direction D. Similarly, the observation direction D can be the optical axis. For example, the detection field of view (FOD) is larger than the field of view (FOV). Therefore, the detection field of view (FOD) can have an angle larger than the angular size of the field of view (FOV). Figure 2 The observation direction P of camera system 11 and the observation direction D of optical detector 1 are collinear; however, in principle, an angle can also exist between observation directions D and P. The detection field of view (FOD) and field of view (FOV) are also... Figure 3 As shown in the diagram. For example, the field of view (FOV) is rectangular or approximately rectangular. The detection field of view (FOD) is composed of color detection regions A. For example, in a plane perpendicular to the observation direction D of the optical detector 1, region A is circular or elliptical. For example, there are 3 × 3 regions A. Along the diagonal of the detection field of view (FOD), there can be regions A1, A2, A3 corresponding to the sensitivity directions C1, C2, C3 that are collinear with the observation direction D of the optical detector 1 and / or with the observation direction of the optical detector. Because the detection field of view (FOD) is larger than the field of view (FOV) of the camera system 11, effective white balance can be performed on the entire field of view (FOV).

[0063] Figure 4 and Figure 5 A modified optical detector 9 is shown. The modified optical detector 9 has multiple arrays 25. In each of the arrays 25, there are multiple first sensors 21. Each array 25 is sensitive to a specific spectral subrange within the visible spectrum. The corresponding subrange can be adjusted using a color filter 51 (such as a Bragg filter or a colored filter).

[0064] For example, there are at least three or at least six spectral sub-ranges, and / or there are at most 36, at most 25, or at most 16 spectral sub-ranges. For example, according to Figure 4There are twelve arrays of 25 that can be assigned to violet, violet-blue, cyan-green, turquoise, green, yellow-green, yellow-green, yellow, yellow-orange, orange, red, and magenta, for example, by referring to the CIE chromaticity diagram to identify these colors. Therefore, the number of arrays of 25 can correspond to the number of colors, also known as color channels.

[0065] Each array 25 includes multiple first sensors 21, such as silicon-based photodiodes. Each first sensor 21 can be a single-channel detector. The first sensors 21 are covered by a common color filter 51; however, individual color filters 51 may also be present. No two first sensors 21 have the same sensitivity direction C. Therefore, the number of different sensitivity directions C can correspond to the number of first sensors 21 in the respective array 25. It is possible that all arrays 25 have the same set of sensitivity directions C, such that the arrays 25 may differ only in their spectral sensitivity and not in their spatial sensitivity.

[0066] like Figure 5 As shown, the sensitivity direction C is defined by means of an aperture plate 3. The aperture plate 3 includes a continuous substrate 30. For example, the substrate 30 is made of a material that transmits in the visible spectrum, such as glass or plastic, like polycarbonate or polymethyl methacrylate. The total thickness of the substrate 30 is, for example, at least 0.1 mm and / or at most 1 mm. The substrate 30 can be a mechanically flexible foil or a rigid body.

[0067] The aperture sheet 3 also includes a first layer 31 and a second layer 32 applied to opposite main sides of the substrate 30, respectively. Layers 31 and 32 are made of an opaque material (e.g., black chrome) or of an opaque layer stack (e.g., a Bragg layer sequence that may contain an absorbing material (e.g., silicon).

[0068] In the first layer 31 and the second layer 32, there are first apertures 41 and second apertures 42, respectively. For example, apertures 41 and 42 are circular. Visible light can travel through apertures 41 and 42. All apertures 41 and 42 assigned to a specific first sensor in the first sensor 21 constitute an aperture stack 44. Each aperture stack 44 corresponds exactly to one first sensor 21, and vice versa. The sensitivity direction C is determined by means of the aperture stack 44, that is, by means of the relative positions of apertures 41 and 42.

[0069] like Figure 5 As shown, optical refraction occurs at the top surface of the aperture plate 30, which is immediately adjacent to the first layer 31 and far from the first sensor 21. For example, when the refractive index of the substrate 30 is about 1.5, the maximum incident angle entering the substrate 30 is about 40° because total internal reflection occurs at a larger incident angle.

[0070] To compensate for the possible dependence of transmission through color filter 51 on the angle of incidence, a diffuser 55 may optionally be present. For example, diffuser 55 is a matrix material embedded with light-scattering particles and / or a light-transmitting layer having one or two roughened main sides.

[0071] Optionally, the first sensor 21 is disposed on a substrate 53 (such as a circuit). For simplicity, no electrical wiring is shown in the figures. For example, the substrate 53 is attached to the aperture plate 3 with an adhesive 54 (such as clear glue). Alternatively, if the substrate 53 is not present, the first sensor 21 may be attached individually to the aperture plate 3, or the color filter 51 and / or diffuser 55 may serve as a carrier for all or a group of first sensors 21.

[0072] In addition, regarding Figures 1 to 3 The content can also be applied to Figure 4 and Figure 5 And vice versa.

[0073] For example, if the ambient light is based on an artificial light source, it can be periodic, such as 50 Hz. This periodicity of the ambient light can also be referred to as flicker. If the first sensor 21 is not synchronized with the frequency of the artificial light source, the color measurement of the ambient light may be distorted, and white balance may be impaired. Therefore, flicker detection is required for accurate white balance. However, flicker sensors may potentially lead to additional space requirements, thus increasing costs. By employing the flicker sensor of the optical detector 1 described herein, no additional space is required.

[0074] exist Figure 6 and Figure 7 The image shows an embodiment of an optical detector 1 focused on a scintillation sensor. Regarding the first sensor 21, the array 25, and the aperture plate 3, particularly regarding... Figure 4 and Figure 5 The content can also be applied to Figure 6 and Figure 7 .

[0075] The sensitivity direction C of the first sensor 21, which is arranged around the center of the first sensor 21, points outward (i.e., away from the observation direction D of the optical detector 1, such as...). Figure 2 In the case shown, the corresponding apertures 41 and 42 increase the size requirements of the array 25. Therefore, the distance between adjacent first sensors 21 within the array 25 is smaller than the distance between adjacent first sensors 21 in different arrays 25. Thus, there is some available space between the first sensors 21 in different arrays 25. A second sensor 22 for scintillation detection is positioned within this space. The second sensor 22 may not be limited to a specific spectral range within the visible spectrum.

[0076] The second sensor 22 does not have its own aperture in the first layer 31, but instead uses the first aperture 41 of the adjacent first sensor 21. Figure 6 In the top view, the four first apertures 41 overlap with the light incident surface 20 of the second sensor 22, so the light incident surface 20 partially overlaps with the four first apertures 41.

[0077] Through these first apertures 41, the second sensor 22 can detect light from directly above the second sensor 22 and over a wide angular range (e.g., the incident light reaching the aperture plate 3 has a total internal reflection angle of up to about 40°). Therefore, the second sensor 22 can be sensitive over the entire angular range also covered by all the first sensors 21.

[0078] The distances between arrays 21 and the size and / or position of the second sensor 22 between arrays 21 are selected such that the distances between the respective first apertures 41 are at least 20 μm, at least 50 μm, or at least 100 μm. For example, this distance is at most 90% or at most 80% of the extension of the second sensor 22 along the respective distance direction. Therefore, the width of the remaining opaque region of the first layer 31 can be less than the width of the second sensor 22 along the same direction.

[0079] The size of the first aperture 41 of the adjacent first sensors 21 in different arrays 25 and facing the second sensor 22 can be selected such that the maximum angle of incidence of light onto the corresponding first sensor 21 corresponds to the critical angle of total internal reflection. Therefore, even a more extended first aperture 41 will not allow light with a smaller angle of incidence to reach the corresponding first sensor 21.

[0080] The second layer 42, adjacent to the second sensor 22, also includes a scintillation aperture 45. The scintillation aperture 45 partially covers the light incident surface 20 of the second sensor 22. The light incident surface 20 can be arranged parallel to the second layer 42 and therefore to the scintillation aperture 45.

[0081] Alternatively, the substrate 30 can be composed of multiple sub-pieces 301, 302. An intermediate layer 33 may exist between adjacent sub-pieces 301, 302, comprising intermediate apertures 43 for allocation to aperture stacks 44 of the first sensor 21. The edges of all apertures 41, 42, 43 of one aperture stack 44 can define a cone of the respective aperture stack 44. All cones may widen in a direction away from the first sensor 21. Optical crosstalk between adjacent first sensors can be reduced by means of at least one intermediate layer 33. In principle, using more intermediate layers 33 can achieve a smaller distance between the first sensors 21.

[0082] For the second sensor 22, an additional scintillation aperture 46 may exist in the intermediate layer 43. For example... Figure 7 As shown, the scintillation aperture 45 and the additional scintillation aperture 46 can be identical or approximately identical. The distance between the second sensor 22 and the nearby first sensor 21 can be less than the distance between adjacent first sensors within the array 25. This is possible because the second sensor 22 does not need to have its own aperture in the first layer 31.

[0083] For example, the entire aperture sheet 3 can be planar parallel. Sub-sheets 301 and 302 can, for example, each have a thickness of at least 50 μm and / or at most 300 μm. Sub-sheets 301 and 302 can have different thicknesses, wherein the first sub-sheet 301 immediately adjacent to the first layer 31 can be thicker than the second sub-sheet 302 immediately adjacent to the second layer 32. For example, the thickness of the first sub-sheet 301 is between 110% and 200% or between 120% and 170% of the thickness of the second sub-sheet 302. Figure 7 Unlike the example shown, there can be more than two sub-pieces and correspondingly more than one intermediate layer 33.

[0084] Therefore, due to the refractive index of the substrate 30, the maximum possible angle of incidence is limited to approximately 40°. Consequently, the region between the apertures 42 and 43 of the middle and bottom aperture layers 42 and 43 of the array 25 of spectral channels has no optical relevance for compound eye detection. This region can be used to detect crosstalk signals using an additional unfiltered detector region (i.e., the light incident surface 20 of the second sensor 22). The additional detector 22 (without a spectral filter) collects light passing through the four corner apertures 41 of the upper aperture layer 31. Through the optimized aperture layer design, this covers and overlaps the entire detection field of view (FOD) of all the first sensors 21.

[0085] In addition to color filter 51, an infrared filter (not shown) may also be present. This infrared filter can block infrared radiation, especially away from the second sensor 22. For example, this infrared filter is opaque above 780 nm, extending down to at least the absorption edge of the second sensor 22, which is, for example, around 1.1 μm.

[0086] Alternatively, the processing unit 12 for synchronizing the first sensor 21 with the flicker signal measured by the second sensor 22 is part of the optical sensor 12. Therefore, the optical sensor 12 may not require the processor resources of the image recording device itself to synchronize the data acquisition of the first sensor 21 with the flicker frequency of the ambient light.

[0087] In addition, regarding Figures 1 to 5 The content can also be applied to Figure 6 and Figure 7And vice versa.

[0088] Figure 8 It is shown that the scintillation aperture 45 and the additional scintillation aperture 46 do not need to be identical. For example, the scintillation aperture 45 may be larger than the additional scintillation aperture 46. Preferably, the scintillation aperture 45 and the additional scintillation aperture 46 are directly surrounded in all directions by an opaque material or an opaque layer sequence of the second layer 32 and the intermediate layer 33.

[0089] In addition, regarding Figures 1 to 7 The content can also be applied to Figure 8 And vice versa.

[0090] Figure 9 Several variations of the configuration of the second sensor 22 are shown. These different configurations can be used individually or in any combination with the optical detector 1.

[0091] The second sensor 22 can use a different number of first apertures 41. For example, the central second sensor 22A uses four first apertures 41, similar to... Figure 6 As shown. Alternatively, the second sensor 22A can be segmented, for example divided into four segments corresponding to the four first apertures 41. Optionally, the electrical signals of each segment can be evaluated separately to obtain spatially resolved scintillation information.

[0092] The second sensors 22D, 22E, and 22F each use two first apertures 41, with the second sensors 22E and 22F located between the middle portions of adjacent arrays 25, and the second sensor 22D located at the corner of two boundary arrays 25. Optionally, the second sensors 22D and 22F can also be segmented, similar to the second sensor 22A.

[0093] The second sensors 22B and 22C use only one first aperture 41. The second sensor 22B is located at the edge of the overall arrangement of the first sensor 21, while the second sensor 22C is located in the middle section of a boundary array 25.

[0094] Alternatively, the second sensors 22E and 22F may not be located at the center between two adjacent first sensors 21, but may be shifted along the edge of the adjacent array 25, so that these second sensors 22E and 22F can also use four first apertures 41. Similarly, for example, the second sensor 22C may be shifted along the boundary edge, so that it can use two first apertures 41. If more elongated second sensors 22C, 22E, and 22F are used, more first apertures 41 may be involved.

[0095] In addition, regarding Figures 1 to 8 The content can also be applied to Figure 9 And vice versa.

[0096] Therefore, different numbers of first apertures 41 and aperture layers 31, 32, and 33 can be used. This can be achieved from a single monochromatic compound eye sensor with four surrounding scintillation structures to a multispectral sensor with structures in between. A filter can be used on the scintillation sensor 22 for infrared blocking. Various geometries of scintillation apertures 45 and 46 and sensor geometries (see...) Figure 9 It is possible, especially as long as it does not obstruct the optical path of spectral channel 25. The scintillation sensor 22 can be divided into multiple segments. The second sensor 22 is possible at various locations, such as corners, boundaries, or the middle, see also... Figure 9 Overall scintillation signal processing can be the sum of all scintillation sensors or all segments, and may only require a single modulator to process a single scintillation channel; otherwise, multiple modulators are used to implement separate signal processing, providing segment information about the scintillation in the scene. A structured thin-film diffuser 55 can be used, eliminating the need for filters and diffusers on the scintillation sensor 22, thereby reducing internal crosstalk due to high absorption, since the light incident surface 20 of the second sensor 22 may have similar high absorption as the aperture layers 31, 32, and 33.

[0097] exist Figure 10 The diagram shows a block diagram of the manufacturing method. In step M1, a substrate 53 is provided. The substrate 53 supports a first sensor 21 and a second sensor 22. The substrate can be a permanent substrate present in the finished optical sensor or a temporary substrate to be removed later. According to step M2, an aperture plate 3 is provided.

[0098] In method step M3, the aperture plate 3 is attached to the substrate 53, for example by gluing.

[0099] The aperture plate 3 can be produced, for example, using photolithography. Therefore, the positioning tolerances of apertures 41, 42, 43, 45, and 46 relative to each other can be relatively small, such as at most 5 μm or at most 1 μm.

[0100] On the other hand, the positioning tolerances of the first sensor 21 and the second sensor 22 relative to each other and the aperture plate 3 relative to the substrate 53 can be relatively large, for example, at least 10 μm, or at least 20 μm, or at least 30 μm.

[0101] Therefore, the edge lengths of sensor chips 21 and 22 are, for example, larger than the second aperture 42 and at least one scintillation aperture 45, by at least twice the positioning tolerance. For example, if the positioning tolerance of the first sensor 21 relative to each other and the aperture plate 3 relative to the substrate 53 is T, and the diameter of the second aperture 42 is D, then E ≥ D + 2T applies. Therefore, it can be ensured that the second aperture 42 is always positioned on the assigned first sensor 21. The same applies similarly to the second sensor 22 and the scintillation aperture 45.

[0102] For example, the second sensor 22 has an edge length of at least 200 μm and at most 300 μm. For example, the first sensor 21 has an edge length of at least 100 μm and at most 200 μm.

[0103] In addition, regarding Figures 1 to 9 The content can also be applied to Figure 10 And vice versa.

[0104] Unless otherwise specified, the components shown in the figure are exemplarily positioned one on top of another in the specified order. Components that do not touch in the figure are spaced apart from each other as an example. If parallel lines are drawn, the corresponding surfaces may be oriented parallel to each other. Similarly, unless otherwise indicated, the positions of the drawn components relative to each other are correctly reproduced in the figure.

[0105] The invention described herein is not limited to the description based on the exemplary embodiments. Rather, the invention covers any new features and any combination of features, particularly any combination of features in the patent claims, even if the feature or combination itself is not expressly specified in the patent claims or exemplary embodiments.

[0106] This patent application claims priority to German patent application 10 2024 110 765.0, the disclosure of which is incorporated herein by reference.

[0107] Figure Labels

Claims

1. An optical detector (1), comprising: - Aperture plate (3), comprising a first layer (31) and a second layer (32). - Multiple first sensors (21) are located at the second layer (32), and - A second sensor (22), having a light incident surface (20) and also located at the second layer (32), in, - For each of the first sensors (21), a first aperture (41) and a second aperture (42) exist in the first layer (31) and the second layer (32), respectively, such that for each of the first sensors (21), there exists an aperture stack (44) that defines the sensitivity direction (C) of the corresponding first sensor in the first sensor (21), and - The second sensor (22) has a line of sight (S) through at least one of the first apertures (41) and another line of sight perpendicular to the light incident surface (20).

2. The optical detector (1) according to the preceding claim further includes a detection timer (52), wherein, - Each first sensor (21) has exactly one of the aperture stacks (44). - For each of the first sensors (21), there is a color filter (51) such that the first sensor (21) is sensitive only within a subrange of the visible spectrum. - The second sensor (22) is sensitive across the entire visible spectrum. - The second sensor (22) is configured to generate a time-dependent flicker signal, and - The detection timer (52) is configured to synchronize the detection time interval of the first sensor (21) with the flashing signal.

3. The optical detector (1) according to any one of the preceding claims. in, The first layer (31) has no aperture dedicated to the second sensor (22) and is not part of at least one aperture stack in the aperture stack (44), such that the line of sight (S) of the second sensor (22) passes only through at least one first aperture in the first aperture (41), and The second layer (32) includes a scintillation aperture (45) specifically allocated to the second sensor (22).

4. The optical detector (1) according to the preceding claim, wherein, From a top view of the light incident surface (20), the scintillation aperture (45) partially covers the light incident surface (20) of the second sensor (22).

5. The optical detector (1) according to any one of the preceding claims, wherein, From a top view of the light incident surface (20), the light incident surface (20) of the second sensor (22) partially overlaps with at least one of the first apertures (42) that define the line of sight (S).

6. The optical detector (1) according to any one of the preceding claims. in, The aperture plate (3) includes one or more intermediate layers (33) located between the first layer (31) and the second layer (32). Wherein, each of the intermediate layers (33) includes an intermediate aperture (43) specifically assigned to one of the aperture stacks (44), and Each of the intermediate layers (33) includes an additional scintillation aperture (46) specifically allocated to the second sensor (22).

7. The optical detector (1) according to the preceding claim, wherein, The additional scintillation aperture (46) of the intermediate layer (43) and the scintillation aperture (45) of the second layer (42) are equal, or the scintillation aperture (45) is larger than the additional scintillation aperture (46).

8. The optical detector (1) according to any one of the preceding two claims, wherein, There is exactly one of the intermediate layers (33), or there are two or three of the intermediate layers (33).

9. The optical detector (1) according to any one of the preceding claims, wherein, Each of the aperture stacks (44) widens along the sensitivity direction (C) and away from the second layer (32).

10. The optical detector (1) according to any one of the preceding claims. in, The first sensor (21) is arranged in a plurality of arrays (25), each of the arrays (25) being sensitive to a specific color and including a plurality of the first sensors (21). The number of the first sensors (21) in each of the arrays (25) is the same as the number of the sensitivity directions (C) in the corresponding array in the array (25), and the sensitivity directions (C) are different in pairs.

11. The optical detector (1) according to the preceding claim. in, From the top view of the second layer (32), the distance between adjacent first sensors (21) in the array (25) is smaller than the distance between adjacent arrays in the array (25). The second sensor (22) is located between the arrays (25).

12. The optical detector (1) according to any one of the preceding claims, wherein, The number of the first sensors (21) in each of the arrays (25) is at least four and at most 25.

13. The optical detector (1) according to any one of the preceding claims, comprising a plurality of the second sensors (22), wherein, The second sensor (22) has a different sensitivity direction (F).

14. The optical detector (1) according to any one of the preceding claims. in, The aperture plate (3) comprises a continuous non-porous substrate (30). The first layer (31) and the second layer (32) are applied to the main side surface of the substrate (30), and The substrate (30) has a refractive index of at least 1.4 and at most 1.8 at 532 nm and 300 K.

15. An image recording device (10), comprising: - Optical detector (1) according to any one of the preceding claims. - The camera system is configured to capture images in the visible spectrum, and - Processing unit (12) The processing unit (12) is configured to calculate the white balance of the image captured by the camera system using data from the optical detector (1).

16. A method for manufacturing an optical detector (1) according to any one of claims 1 to 14, comprising: - Provide a substrate (53) for carrying the first sensor (21) and the second sensor (22). - Provide the aperture plate (3) having the first layer (31) and the second layer (32), and - Attach the aperture plate (3) to the substrate (53).

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