Multispectral chip assembly and preparation method thereof

Abstract

The invention provides a multispectral chip assembly and a preparation method thereof. The multispectral chip assembly preparation method comprises the steps that an image sensor is obtained, the image sensor is used for obtaining light rays of different wavebands so as to obtain spectral information of each channel, and different channels correspond to the spectral information of different wavebands; a light filtering layer is formed on a light sensing path of the image sensor, and the light filtering layer is used for filtering light entering the image sensor and enabling light of at least four different wave bands to pass through. According to the multispectral chip assembly preparation method, the filter layer is formed on the photosensitive path of the image sensor, so that the light of the image sensor comprises at least four different wavebands, at least four spectral channels can be realized, the number of the channels is increased, and multispectral imaging is realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of multi-spectral chip assembly, in particular to a multi-spectral chip assembly and a preparation method thereof. BACKGROUND

[0002] Image sensing technology is a key link of modern information acquisition, and is widely used in many fields such as consumer electronics, industrial detection, security monitoring, automatic driving, biomedical imaging, etc. Among them, the RGB (red, green, blue) color image sensor has become the mainstream solution in the current market because of its mature technology, controllable cost and high integration.

[0003] The RGB image sensor in the related art has the technical problem of limited number of spectral channels. SUMMARY

[0004] Embodiments of the present application provide a multi-spectral chip assembly and a preparation method thereof.

[0005] In a first aspect, embodiments of the present application provide a multi-spectral chip assembly preparation method, comprising:

[0006] obtaining an image sensor, the image sensor being configured to obtain light of different wavebands to obtain spectral information of each channel, wherein different channels correspond to spectral information of different wavebands;

[0007] forming a filter layer on a light sensing path of the image sensor, the filter layer being configured to filter light entering the image sensor and allowing at least four different wavebands of light to pass through.

[0008] In an embodiment, after the step of forming the filter layer on the light sensing path of the image sensor, the method further comprises:

[0009] encapsulating the image sensor and the filter layer in a housing.

[0010] In an embodiment, the step of forming the filter layer on the light sensing path of the image sensor comprises:

[0011] stacking the filter layer at a light sensing lens of the image sensor.

[0012] In an embodiment, the step of obtaining the image sensor comprises:

[0013] obtaining an image sensor based on a CSP packaging process; or

[0014] obtaining an image sensor based on a COB packaging process; or

[0015] obtaining an image sensor in the form of a bare chip.

[0016] In an embodiment, the step of acquiring the image sensor comprises:

[0017] The image sensor is an RGB image sensor.

[0018] In a second aspect, embodiments of the present application provide a multi-spectrum chip assembly prepared by the multi-spectrum chip assembly preparation method as described above.

[0019] In an embodiment, the multi-spectrum chip assembly comprises:

[0020] an image sensor configured to acquire light of different wavebands to obtain spectral information of each channel, wherein different channels correspond to spectral information of different wavebands;

[0021] a filter layer arranged on a light path of the image sensor, the filter layer configured to filter light entering the image sensor and allow at least four different wavebands of light to pass through;

[0022] wherein the waveband range of light that can pass through the filter layer is within the waveband range of light that can be acquired by the image sensor.

[0023] In an embodiment, the multi-spectrum chip assembly further comprises a housing, and the image sensor and the filter layer are both encapsulated in the housing.

[0024] In an embodiment, along the light path direction of the filter layer, the image sensor is projected on the bottom of the housing coinciding with the projection of the filter layer on the bottom of the housing; or,

[0025] along the light path direction of the filter layer, the image sensor is projected on the bottom of the housing within the projection of the filter layer on the bottom of the housing.

[0026] In a third aspect, embodiments of the present application provide an electronic device comprising the multi-spectrum chip assembly as described above.

[0027] The beneficial effects of embodiments of the present application are as follows:

[0028] In the embodiment of the present application, by forming the light filtering layer on the light sensing path of the image sensor, the light will pass through the light filtering layer before entering the image sensor, the light filtering layer can filter the light entering the image sensor, so that at least four different wavebands of light enter the image sensor. The waveband range of the light that can pass through the light filtering layer is within the waveband range of the light that the image sensor can obtain, which ensures that the image sensor can normally image. That is, by forming the light filtering layer on the light sensing path of the image sensor, the light entering the image sensor includes at least four different wavebands, at least four spectral channels can be realized, and the number of channels is increased, and multispectral imaging is realized. BRIEF DESCRIPTION OF DRAWINGS

[0029] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0030] Figure 1 is a structural schematic diagram of a multispectral chip assembly provided by an embodiment of the present application, and the arrow in the figure indicates the light transmission direction;

[0031] Figure 2 is a structural schematic diagram of a multispectral chip assembly provided by an embodiment of the present application, and the arrow in the figure indicates the light transmission direction;

[0032] Figure 3 is a structural schematic diagram of a light filtering plate provided by an embodiment of the present application;

[0033] Figure 4 is one of structural exploded schematic diagrams of a multispectral chip assembly provided by an embodiment of the present application, and the arrow in the figure indicates the light transmission direction;

[0034] Figure 5 is another structural exploded schematic diagram of a multispectral chip assembly provided by an embodiment of the present application, and the arrow in the figure indicates the light transmission direction;

[0035] Figure 6 is a structural schematic diagram of a light filtering layer provided by an embodiment of the present application;

[0036] Figure 7 is a wavelength-quantum efficiency schematic diagram provided by an embodiment of the present application;

[0037] Figure 8 is a parameter table provided by an embodiment of the present application;

[0038] Figure 9 is a wavelength-quantum efficiency schematic diagram provided by an embodiment of the present application;Figure 8 a spectral curve corresponding to a parameter table

[0039] Figure 10 a wavelength-quantum efficiency curve provided by an embodiment of the present application;

[0040] Figure 11 a structural diagram of a multi-spectrum chip assembly provided by an embodiment of the present application, wherein the light filtering layer has four light filtering areas, and each light filtering area can transmit light of 7 different wave bands;

[0041] Figure 12 a flowchart of a multi-spectrum chip assembly preparation method provided by an embodiment of the present application. DETAILED DESCRIPTION

[0042] The technical solutions in the embodiments of the present application will be clearly and completely described with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of the present application. In addition, it should be understood that the specific implementation described herein is only used to illustrate and explain the present application, and is not used to limit the present application. In the present application, the orientation words such as "upper" and "lower" generally refer to the upper and lower of the device in the actual use or working state, and specifically refer to the direction of the drawing surface in the drawings; and "inner" and "outer" refer to the outline of the device.

[0043] The multi-spectrum chip assembly and the electronic device of the present application will be described below. Figures 1 to 12 The multi-spectrum chip assembly and the electronic device of the present application will be described below. Figure 2 In the embodiment, the light filtering layer 2 is a 6-channel light filtering layer, and the image sensor 1 is an RGB image sensor. Figure 7 In the embodiment, R, G, B and X respectively represent four light sensing wave bands of the image sensor, and CH1, CH2, CH3, CH4, CH5, CH6, CH7 and CH8 respectively represent 8 different wave bands that can be transmitted by the light filtering layer 2.

[0044] According to the embodiment of the first aspect of the present application, as Figure 1 and Figure 2 The multi-spectrum chip assembly comprises an image sensor 1 and a light filtering layer 2. The image sensor 1 is used to acquire light of different wave bands to obtain spectral information of each channel, wherein different channels correspond to spectral information of different wave bands. The light filtering layer 2 is arranged on a light sensing path of the image sensor 1. The light filtering layer 2 is used to filter light entering the image sensor 1 and make at least four different wave bands of light pass through.

[0045] The wavelength range of the light that can pass through the light filtering layer 2 is within the wavelength range of the light that can be acquired by the image sensor 1.

[0046] According to the multispectral chip assembly provided in the embodiments of the present application, the light filtering layer 2 is arranged on the light sensing path of the image sensor 1, so that the light enters the image sensor 1 through the light filtering layer 2 first. The light filtering layer 2 can filter the light entering the image sensor 1, so that at least four different wavelengths of light enter the image sensor 1. The wavelength range of the light that can pass through the light filtering layer 2 is within the wavelength range of the light that can be acquired by the image sensor 1, so that the image sensor 1 can normally image. That is, the present application arranges the light filtering layer 2 on the light sensing path of the image sensor 1, so that the light entering the image sensor 1 includes at least four different wavelengths, at least four spectral channels can be realized, the number of channels is increased, and multispectral imaging is realized.

[0047] It can be understood that the present application directly adds the light filtering layer 2 on the light sensing path of the image sensor 1, without changing the pixel points of the image sensor 1, so that more spectral channels can be realized without sacrificing spatial resolution. The image sensor 1 can be an existing RGB image sensor 1 or other image sensor 1, so that the multispectral chip assembly can be quickly and low-costly obtained.

[0048] In some examples, the light filtering layer 2 can pass a through a plurality of different wavelengths of light, and the light filtering structure of the image sensor 1 can pass b through a plurality of different wavelengths of light, where a is greater than b.

[0049] Specifically, when b is not greater than 3, a can be greater than b, and the number of spectral channels can be increased by the light filtering layer 2 at this time.

[0050] Specifically, when b is greater than 3, a can be greater than or equal to b. When a is equal to b, the image sensor 1 can realize at least four spectral channels at this time. Since the wavelength range of the light that can pass through the light filtering layer 2 is within the wavelength range of the light that can be acquired by the image sensor 1, the light filtering layer 2 cannot increase the number of spectral channels at this time, but can narrow the light sensing wavelength range of the image sensor 1 to improve the light sensing effect.

[0051] It can be understood that the related art RGB image sensor 1 has only three spectral channels of R, G and B, and the number of channels is small. The present application adds the light filtering layer 2 on the light sensing path of the image sensor 1, so that at least four different wavelengths of light pass through the light filtering layer 2, and the light entering the image sensor 1 includes at least four different wavelengths. Therefore, the multispectral chip assembly provided in the present application has at least four spectral channels, the number of channels is effectively increased, and multispectral imaging can be realized.

[0052] The multispectral implementation scheme in the related art has the following problems: 1. Generally, each pixel point has an independent light splitting unit for each channel, which has complex process, long production cycle, low yield and high cost; 2. When multiple channels are arranged in space, the spatial resolution is sacrificed, and the spatial distance between the same channels is too long, so that more channels are difficult to achieve.

[0053] The present application can directly set the filter layer 2 on the existing image sensor 1, filter the light entering the image sensor 1 through the filter layer 2, so that the light entering the image sensor 1 includes at least four wave bands, and the image sensor 1 can realize at least four spectral channels to realize multispectral imaging. That is, by setting the filter layer 2 on the light sensing path of the image sensor 1, a multispectral chip assembly can be obtained, which has simple process, short production cycle, high yield, low cost, and at least part of the pixel points can realize multiple channels, and the spatial resolution is guaranteed.

[0054] In an embodiment of the present application, the wave band width of the light of at least part of the wave bands that can pass through the filter layer 2 is smaller than the wave band width of the light of at least one of the wave bands that can be acquired by the image sensor 1, thereby reducing the light sensing wave band width of the image sensor 1, which is beneficial to improve the imaging accuracy.

[0055] In an embodiment of the present application, the image sensor 1 is, for example, an RGB image sensor 1. It should be noted that this is only an example of the image sensor 1 and does not have special limitations. The image sensor 1 can also be any other suitable sensor, such as an infrared sensor.

[0056] Specifically, the filter layer 2 can pass multiple different wave bands, including a first wave band set, a second wave band set and a third wave band set. The wave band range of the first wave band set is within the wave band range of the green channel of the RGB image sensor 1, the wave band range of the second wave band set is within the wave band range of the green channel of the RGB image sensor 1, and the wave band range of the third wave band set is within the wave band range of the blue channel of the RGB image sensor 1. The first wave band set, the wave band set and the third wave band set each include at least one wave band.

[0057] That is, the wave band range of the light of at least one wave band is within the wave band range of the red channel of the RGB image sensor 1, the wave band range of the light of at least one wave band is within the wave band range of the green channel of the RGB image sensor 1, and the wave band range of the light of at least one wave band is within the wave band range of the blue channel of the RGB image sensor 1, thereby ensuring that the R pixel point 13, the G pixel point 14 and the B pixel point 15 of the RGB image sensor 1 can all be light sensitive, avoiding the situation that part of the pixel points are idle.

[0058] Specifically, the filter layer 2 can allow n different bands of light to pass through, wherein the first band set, the second band set and the third band set each include n / 3 bands.

[0059] That is, the band range of n / 3 bands of light is within the band range of the red channel of the RGB image sensor 1, the band range of n / 3 bands of light is within the band range of the green channel of the RGB image sensor 1, and the band range of n / 3 bands of light is within the band range of the blue channel of the RGB image sensor 1, so that each pixel unit can implement n / 3 spectral channels.

[0060] And the filter layer 2 can allow at least four different bands of light to pass through, then n is greater than or equal to 6, that is, each pixel unit can implement at least two spectral channels, and the R pixel unit, the G pixel unit and the B pixel unit together can implement at least 6 spectral channels, thereby realizing multispectral.

[0061] In an embodiment of the present application, as Figure 1 The spectral chip further includes a shell 3, and the image sensor 1 and the filter layer 2 are packaged in the shell 3.

[0062] It can be understood that packaging the image sensor 1 and the filter layer 2 together to obtain a multispectral chip assembly improves the integration of the multispectral chip assembly.

[0063] In an embodiment of the present application, the image sensor 1 has a photosensitive lens, and the filter layer 2 is connected to the photosensitive lens.

[0064] It can be understood that directly arranging the filter layer 2 on the photosensitive lens of the image sensor 1 can make the filter layer 2 filter the light entering the image sensor 1, which is simple to operate.

[0065] In some examples, the image sensor 1 is, for example, a CSP packaged image sensor 1, that is, the image sensor 1 can be an image sensor 1 obtained based on a CSP packaging process.

[0066] In some examples, the image sensor 1 is, for example, a COB packaged image sensor 1, that is, the image sensor 1 can be an image sensor 1 obtained based on a COB packaging process.

[0067] In an embodiment of the present application, as Figure 3The image sensor 1 comprises a filter 11, the filter 11 comprises at least one filter unit module 12, each filter unit module 12 comprises an R filter unit 121, a G filter unit 122, a B filter unit 123 and at least one extended filter unit 124, the R filter unit 121 is used for allowing light of a red band to pass through, the G filter unit 122 is used for allowing light of a green band to pass through, the B filter unit 123 is used for allowing light of a blue band to pass through, and the extended filter unit 124 is used for allowing light of a specific band to pass through, and any one of the red band, the green band and the blue band is different from the specific band.

[0068] It can be understood that the filter 11 of the image sensor 1 can allow light of the red band, the green band, the blue band and the specific band to pass through, and the image sensor 1 comprises at least four pixel units, that is, the image sensor 1 can implement at least four spectral channels. Assuming that the filter layer 2 can allow light of a different band to pass through, by the setting of the extended filter unit 124, the light sensing range of the image sensor 1 is increased, and then the upper limit value of a is improved, that is, the number of spectral channels that can be implemented by the multispectral chip assembly is increased.

[0069] When the filter layer 2 allows light of at least five different bands to pass through, the filter layer 2 can allow light of at least five different bands to enter the image sensor 1, and then the number of spectral channels that can be implemented by the image sensor 1 is increased.

[0070] When the filter layer 2 allows light of four different bands to pass through, although the filter layer 2 cannot increase the number of spectral channels, the light sensing band width of the image sensor 1 can be narrowed to improve the light sensing effect.

[0071] Specifically, as Figure 3 The extended filter unit 124 comprises an X filter unit 1241, and the X filter unit 1241 is used for allowing light of a specific band to pass through. By the setting of the X filter unit 1241, the light sensing range of the image sensor 1 is increased, and the number of spectral channels that can be implemented by the multispectral chip assembly is increased.

[0072] In some examples, the number of X filter units 1241 is at least two, and different X filter units 1241 are used for allowing light of different bands to pass through. That is, the image sensor 1 can implement at least five spectral channels at this time. Assuming that the filter layer 2 can allow light of a different band to pass through, by the setting of the at least two X filter units 1241, the light sensing range of the image sensor 1 is increased, and then the upper limit value of a is improved, that is, the number of spectral channels that can be implemented by the multispectral chip assembly is increased.

[0073] In an embodiment of the present application, as Figure 4The image sensor 1 includes R pixel points 13, G pixel points 14, B pixel points 15, and an extended pixel point 16. The light wave band acquired by any one of the R pixel points 13, the G pixel points 14, and the B pixel points 15 is different from the light wave band acquired by the extended pixel point 16.

[0074] That is, the image sensor 1 can implement at least four spectral channels. Assuming that the filter layer 2 can make a light of a different wave band pass through, the setting of the extended pixel point 16 increases the light sensing range of the image sensor 1, and thus is conducive to increasing the upper limit value of a, that is, conducive to increasing the number of spectral channels that can be implemented by the multi-spectral chip assembly.

[0075] In some examples, as shown in FIG. 1, Figure 4 The extended pixel point 16 includes at least one X pixel point, and the extended pixel point 16 is used to acquire at least one of long ultraviolet light UA, middle ultraviolet light UB, near infrared light NR, middle infrared light MR, and far infrared light LR. That is, the image sensor 1 can not only sense visible light, but also sense invisible light, thereby increasing the light sensing range of the image sensor 1.

[0076] In an embodiment of the present application, as shown in FIG. 2, Figure 5 The filter layer 2 includes at least four filter regions 20, and each filter region 20 is used to make at least three different wave bands of light pass through. Different filter regions 20 are used to make different wave bands of light pass through.

[0077] That is, the filter layer 2 can make at least 12 different wave bands of light pass through, and thus the image sensor 1 can implement at least 12 spectral channels.

[0078] In some examples, each filter region 20 is used to make 8 different wave bands of light pass through, and thus the filter layer 2 can make 32 different wave bands of light pass through, and thus the image sensor 1 can implement 32 channels.

[0079] In some examples, as shown in FIG. 3, Figure 11The four filter regions 20 include a first filter region, a second filter region, a third filter region, and a fourth filter region. The first filter region can allow light of a first filter wavelength band set to pass through, the second filter region can allow light of a second filter wavelength band set to pass through, the third filter region can allow light of a third filter wavelength band set to pass through, and the fourth filter region can allow light of a fourth filter wavelength band set to pass through. The first filter wavelength band set includes a 410 nm wavelength band, a 450 nm wavelength band, a 480 nm wavelength band, a 550 nm wavelength band, a 610 nm wavelength band, a 650 nm wavelength band, and an 810 nm wavelength band. The second filter wavelength band set includes a 415 nm wavelength band, a 455 nm wavelength band, a 485 nm wavelength band, a 560 nm wavelength band, a 615 nm wavelength band, a 670 nm wavelength band, and an 815 nm wavelength band. The third filter wavelength band set includes a 420 nm wavelength band, a 460 nm wavelength band, a 490 nm wavelength band, a 565 nm wavelength band, a 620 nm wavelength band, a 680 nm wavelength band, and an 820 nm wavelength band. The fourth filter wavelength band set includes a 425 nm wavelength band, a 465 nm wavelength band, a 495 nm wavelength band, a 570 nm wavelength band, a 625 nm wavelength band, a 6805 nm wavelength band, and an 825 nm wavelength band.

[0080] Specifically, the wavelength range of at least one wavelength of light is within the red wavelength range, the wavelength range of at least one wavelength of light is within the green wavelength range, the wavelength range of at least one wavelength of light is within the blue wavelength range, and the wavelength range of at least one wavelength of light is within the specific wavelength range. In this way, it is ensured that at least one wavelength of light can pass through the R filter unit, at least one wavelength of light can pass through the G filter unit, and at least one wavelength of light can pass through the B filter unit, so that the light sensing units of the image sensor can all perform light sensing.

[0081] In an embodiment of the present application, when the central wavelength of the light passing through the filter layer 2 is between 400 nm and 420 nm, the quantum efficiency (QE value) of the multispectral chip assembly is between 38% and 40%; and / or,

[0082] When the central wavelength of the light passing through the filter layer 2 is between 450 nm and 470 nm, the quantum efficiency (QE value) of the multispectral chip assembly is between 50% and 51%; and / or,

[0083] When the central wavelength of the light passing through the filter layer 2 is between 500 nm and 520 nm, the quantum efficiency (QE value) of the multispectral chip assembly is between 53% and 55%; and / or,

[0084] When the central wavelength of the light passing through the filter layer 2 is between 540 nm and 560 nm, the quantum efficiency (QE value) of the multispectral chip assembly is between 51.5% and 52.5%; and / or,

[0085] when the center wavelength of the light transmitted through the filter layer 2 is between 640nm-660nm, the quantum efficiency (QE value) of the multispectral chip assembly is between 40.3%-42%; and / or,

[0086] when the center wavelength of the light transmitted through the filter layer 2 is between 800nm-820nm, the quantum efficiency (QE value) of the multispectral chip assembly is between 16%-19%.

[0087] It can be understood that the spectral chip has a higher quantum efficiency (>50%) in the 450nm-470nm (blue light), 500nm-520nm (cyan light), and 540nm-560nm (yellow-green light) regions, which can more efficiently capture photons of these specific wavelengths, convert them into electrical signals, and significantly improve the light signal detection capability and signal-to-noise ratio of these wavebands.

[0088] It can be understood that the spectral chip maintains a high quantum efficiency in the 640nm-660nm (red light) region, and the spectral response of the chip is highly matched with the characteristic wavelengths of these key biological / chemical indicators, which greatly improves the accuracy and sensitivity of related biological sensors or health monitoring devices.

[0089] It can be understood that ambient light (especially sunlight) is rich in near-infrared light. Reducing the quantum efficiency of the 800nm-820nm band and the 400nm-420nm band can significantly reduce the interference of NIR components in the ambient light on the target visible light signal (especially blue-green light).

[0090] In some examples, as Figure 8 and Figure 9 when the center wavelength of the light transmitted through the filter layer 2 is 410nm, the quantum efficiency of the spectral chip is 39.4%; and / or,

[0091] when the center wavelength of the light transmitted through the filter layer 2 is 460nm, the quantum efficiency of the spectral chip is 50.6%; and / or,

[0092] when the center wavelength of the light transmitted through the filter layer 2 is 510nm, the quantum efficiency of the spectral chip is 54.5%; and / or,

[0093] when the center wavelength of the light transmitted through the filter layer 2 is 550nm, the quantum efficiency of the spectral chip is 52.0%; and / or,

[0094] when the center wavelength of the light transmitted through the filter layer 2 is 650nm, the quantum efficiency of the spectral chip is 40.3%; and / or,

[0095] When the center wavelength of light passing through the filter layer 2 is 810 nm, the quantum efficiency of the spectral chip is 17.3%. In one embodiment of this application, the maximum transmittance of the filter layer 2 is greater than or equal to 90%, which is beneficial for maximizing signal strength, significantly improving the signal-to-noise ratio, and enhancing the accuracy of multispectral data.

[0096] In one embodiment of this application, the filter layer 2 allows light with a center wavelength between 400nm and 420nm to pass through, and the bandwidth of the light with a center wavelength between 400nm and 420nm is between 40nm and 43nm; and / or,

[0097] The filter layer 2 allows light with a center wavelength between 450nm and 470nm to pass through, and the bandwidth of the light with a center wavelength between 450nm and 470nm is between 31nm and 32nm; and / or,

[0098] The filter layer 2 allows light with a center wavelength between 500nm and 520nm to pass through, and the bandwidth of the light with a center wavelength between 500nm and 520nm is between 29nm and 31nm; and / or,

[0099] The filter layer 2 allows light with a center wavelength between 540nm and 560nm to pass through, and the bandwidth of the light with a center wavelength between 540nm and 560nm is between 31.5nm and 33nm; and / or,

[0100] The filter layer 2 allows light with a center wavelength between 640nm and 660nm to pass through, and the bandwidth of the light with a center wavelength between 640nm and 660nm is between 40.5nm and 44nm; and / or,

[0101] The filter layer 2 allows light with a center wavelength between 800nm ​​and 820nm to pass through, and the bandwidth of the light with a center wavelength between 800nm ​​and 820nm is between 98nm and 102nm.

[0102] Understandably, the 400nm-420nm wavelength range is designed to balance the intensity of ultraviolet signals with the complexity of the manufacturing process.

[0103] The 500nm-520nm and 540nm-560nm bands have narrower bandwidths, which can avoid interference from adjacent bands.

[0104] The 450nm-470nm wavelength range has a relatively narrow bandwidth, which is beneficial for optimizing the detection of blue light absorbing substances while suppressing ambient light noise.

[0105] 800nm-820nm corresponds to a relatively wide band width, which is beneficial to improve the near-infrared signal flux, compensate for the low quantum efficiency (QE value) of the band, and ensure the signal-to-noise ratio of the active sensing.

[0106] 640nm-660nm corresponds to a relatively wide band width, which can cover the red light region, balance the sensitivity and anti-interference ability.

[0107] In some examples, as Figure 8 and Figure 9 , the light filter layer 2 can pass light with a center wavelength of 410nm, and the band width of the light with a center wavelength of 410nm is 42nm; and / or,

[0108] The light filter layer 2 can pass light with a center wavelength of 460nm, and the band width of the light with a center wavelength of 460nm is 32.5nm; and / or,

[0109] The light filter layer 2 can pass light with a center wavelength of 510nm, and the band width of the light with a center wavelength of 510nm is 30nm; and / or,

[0110] The light filter layer 2 can pass light with a center wavelength of 550nm, and the band width of the light with a center wavelength of 550nm is 32nm; and / or,

[0111] The light filter layer 2 can pass light with a center wavelength of 650nm, and the band width of the light with a center wavelength of 410nm is 41nm; and / or,

[0112] The light filter layer 2 can pass light with a center wavelength of 810nm, and the band width of the light with a center wavelength of 810nm is 100nm.

[0113] In an embodiment of the present application, the cut-off rate (OD) of the light filter layer 2 is greater than or equal to 2.5, which is beneficial to reduce the influence of interference light, improve the signal-to-noise ratio, improve the independence of each channel spectral data, and reduce the algorithm correction complexity.

[0114] In some examples, as Figure 8 and Figure 9 , the cut-off rate of the light filter layer 2 is greater than or equal to 3, for example.

[0115] In an embodiment of the present application, as Figure 8 and Figure 9 , the error tolerance of the light filter layer 2 is less than or equal to 1%, which is beneficial to ensure the absolute accuracy of the multi-spectral channel and improve the stability.

[0116] It can be understood that the error tolerance refers to the maximum deviation of the key parameters such as the center wavelength shift, the bandwidth change, and the transmittance fluctuation being less than or equal to 1% of the design value.

[0117] In some embodiments, along the light path direction of the filter layer of the shell 3, the orthogonal projection of the image sensor 1 on the bottom of the shell 3 coincides with the orthogonal projection of the filter layer 2 on the bottom of the shell 3, thereby ensuring that the filter layer 2 can effectively filter the light entering the image sensor 1.

[0118] Along the light path direction of the filter layer of the shell 3, the orthogonal projection of the image sensor 1 on the bottom of the shell 3 is within the orthogonal projection of the filter layer 2 on the bottom of the shell 3, thereby ensuring that the filter layer 2 can effectively filter the light entering the image sensor 1.

[0119] It should be noted that the light path direction of the filter layer refers to the transmission direction of the light when the light enters the filter layer.

[0120] In some embodiments, in some embodiments, as Figure 6 , the filter layer includes at least one first filter film 211 and at least one second filter film 212, the refractive index of the first filter film 211 is greater than the refractive index of the second filter film 212, and the first filter film 211 and the second filter film 212 are alternately arranged.

[0121] It can be understood that the first filter film 211 and the second filter film 212 with different refractive indexes are alternately stacked together to form the filter layer, so that the filter layer can transmit at least two different wavebands of light, and multiple different wavebands of light can be obtained by using the same filter layer, that is, the split light structure of multiple wavebands is the same, thereby the filter layer of the present application does not need to be repeatedly etched, cleaned and the like during preparation, and the process is simple and the cost is low.

[0122] In some examples, the present application adopts a multi-layer film technology, and high-refractive-index filter films (such as titanium oxide, specifically titanium oxide or titanium dioxide) and low-refractive-index filter films (such as SiO2) are alternately stacked to form a filter layer. By combining the different thicknesses of the two, at least one narrow-band transmission peak of the light waveband is transmitted through the filter layer, and a single filter layer transmits multiple independent narrow-band transmission peak light wavebands, such as 2, 4, 7, etc. For example, by using one filter layer, four independent narrow-band transmission peak wavebands with center wavelengths of 450 nm, 550 nm, 650 nm, and 750 nm are realized.

[0123] It should be noted that according to the functional requirements and index parameter requirements, the wavelength range of the transmitted narrow-band transmission peak can be (1 nm-100 nm) around the center wavelength, and the full width at half maximum (FWHM) is ≤(1 nm-100 nm) by adjusting the materials used by the first filter film 211 and the second filter film 212, the arrangement mode of the alternating stack of high and low refractive index materials, and the thickness combination mode. For example, if the center wavelength of the transmitted light is 550 nm, the actual transmitted narrow-band transmission peak wavelength range is 550 nm±(1 nm-100 nm), and if the center wavelength is 450 nm, the narrow-band transmission peak wavelength range is 450 nm±(1 nm-100 nm). The crosstalk between multiple narrow-band transmission peaks transmitted by the same filter layer is low enough, such as adjacent band isolation ≥ 30 dB, so that the corresponding quantum corresponding light channel data has sufficient independence.

[0124] In some examples, the material of the first filter film 211 and the second filter film 212 can be any one of aluminum (Al), chromium (Cr), gold (Au), silver (Ag), silicon (Si), germanium (Ge), aluminum oxide (Al2O3), cerium oxide (CeO2), hafnium dioxide (HfO2), indium tin oxide (ITO), magnesium oxide (MgO), niobium pentoxide (Nb2O5), silicon monoxide (SiO), silicon dioxide (SiO2), titanium dioxide (TiO2), titanium trioxide (Ti3O5), tantalum pentoxide (Ta2O5), yttrium oxide (Y2O3), zinc oxide (ZnO), zirconium oxide (ZrO2), aluminum fluoride (AlF3), magnesium fluoride (MgF2), calcium fluoride (CaF2), ytterbium fluoride (YbF3), yttrium fluoride (YF3), zinc sulfide (ZnS), and zinc selenide (ZnSe).

[0125] Specifically, the thicknesses of different first filter films 211 are different.

[0126] It can be understood that when the number of first filter films 211 is at least two, by adjusting the thicknesses of different first filter films 211, the thicknesses of different first filter films 211 are different, and thus the number of wavebands of light that can be transmitted by the filter layer composed of the first filter film 211 can be changed, or the waveband range of the light that can be transmitted by the filter layer can be changed.

[0127] Specifically, the thicknesses of different second filter films 212 are different.

[0128] It can be understood that when the number of second filter films 212 is at least two, by adjusting the thicknesses of different second filter films 212, the thicknesses of different second filter films 212 are different, and thus the number of wavebands of light that can be transmitted by the filter layer composed of the second filter film 212 can be changed, or the waveband range of the light that can be transmitted by the filter layer can be changed.

[0129] Specifically, the thickness of the first filter film 211 and the second filter film 212 is different.

[0130] It can be understood that by adjusting the thickness of the first filter film 211 and the second filter film 212, the number of wave bands of light that can be transmitted by the light filtering layer composed of the first filter film 211 and the second filter film 212 can be changed, or the wave band range of light that can be transmitted by the light filtering layer can be changed.

[0131] In some examples, the thickness of the first filter film 211 and the second filter film 212 can also be the same.

[0132] In some embodiments, the light filtering layer includes at least two filter areas 20, and different filter areas 20 can allow different wave bands of light to pass through.

[0133] It can be understood that different filter areas 20 can transmit different wave bands of light, so that the light filtering layer can simultaneously transmit at least two different wave bands of light.

[0134] Specifically, the thickness of different filter areas 20 is different.

[0135] It can be understood that by making the thickness of the filter medium at different filter areas 20 different, different filter areas 20 can transmit different wave bands of light.

[0136] Specifically, the material of different filter areas 20 is different.

[0137] It can be understood that by making the material of the filter medium at different filter areas 20 different, different filter areas 20 can transmit different wave bands of light.

[0138] The RGB image sensor 1 and the 6-channel light filtering layer 2 are taken as examples to explain the present application as follows:

[0139] As Figure 7 and Figure 10 , the light filtering layer 2 can transmit 6 multi-spectral wave bands, of which two multi-spectral wave bands are within the photosensitive wave band of pixel B, two multi-spectral wave bands are within the photosensitive wave band of pixel G, and two multi-spectral wave bands are within the photosensitive wave band of pixel R. For example, the wave bands of channels CH1 and CH2 are within the photosensitive wave band 400-500 nm of pixel B, the wave bands of channels CH3 and CH4 are within the photosensitive wave band 500-600 nm of pixel G, and the wave bands of channels CH5 and CH6 are within the photosensitive wave band 600-700 nm of pixel R.

[0140] The quantum efficiencies corresponding to the six wave bands CH1, CH2, CH3, CH4, CH5 and CH6 can be detected by the existing device, and the quantum efficiencies of different wave bands are different.

[0141] The mixed photosensitive data of the pixel B can be demixed by combining the photosensitive data of the pixel B, the quantum efficiencies of CH1 and CH2, so as to obtain the photosensitive data corresponding to the CH1 wave band and the CH2 wave band, so that the pixel B can realize dual-channel. Similarly, the pixels R and G can be demixed, and finally the photosensitive data of six channels can be obtained. That is, by adding the filter layer 2 on the image sensor 1, the number of spectral channels can be increased.

[0142] It should be noted that the mixed light can also be demixed by any other suitable method. For example, prism dispersion method, diffraction grating method, interference method, optical fiber spectrum method and filtering method. The prism dispersion method uses the different refractive indexes of different wavelengths of light to make the mixed light disperse after passing through the prism, and separate the different wavelengths of light spectrum. The diffraction grating method uses the diffraction characteristics of the grating to decompose the mixed light into different wavelengths of light spectrum. The interference method uses an interferometer to separate the mixed light into two beams, and separates different wavelengths of light through interference fringes. The optical fiber spectrum method uses the combination of optical fiber and spectrometer to transmit the mixed light to the spectrometer for separation and analysis. The filtering method uses an optical filter to selectively transmit light of a specific wavelength and filter out other wavelengths, and has strong flexibility. It can also select specific wavelengths according to requirements, and is the preferred method for separating spectral channels in multispectral imaging. The separation of mixed light spectrum can also be realized by a calculation method. Common methods include a mixed light spectrum decomposition method based on deep learning and a mixed light decomposition system based on sparse representation.

[0143] When the photosensitive wave band of the image sensor 1 is four or other number, and the number of wave bands that can be transmitted by the filter layer 2 is other number, the demixing principle is the same as the above principle, which will not be described here.

[0144] According to the embodiment of the second aspect of the present application, Figure 12 The multispectral chip assembly preparation method comprises.

[0145] Step 101, obtaining an image sensor 1, the image sensor 1 is used for acquiring light of different wave bands to obtain spectral information of each channel, wherein different channels correspond to spectral information of different wave bands;

[0146] Step 102, forming a filter layer 2 on the photosensitive path of the image sensor 1, the filter layer 2 is used for filtering the light entering the image sensor 1, and at least four different wave bands of light pass through.

[0147] It can be understood that by forming the light filtering layer 2 on the light sensing path of the image sensor 1, the light will pass through the light filtering layer 2 before entering the image sensor 1, and the light filtering layer 2 can filter the light entering the image sensor 1, so that at least four different wavebands of light enter the image sensor 1. The waveband range of the light that can pass through the light filtering layer 2 is within the waveband range of the light that the image sensor 1 can obtain, ensuring that the image sensor 1 can normally image. That is, the present application forms the light filtering layer 2 on the light sensing path of the image sensor 1, so that the light entering the image sensor 1 includes at least four different wavebands, at least four spectral channels can be realized, and the number of channels is increased, realizing multispectral imaging.

[0148] In some embodiments, after the step of forming the light filtering layer 2 on the light sensing path of the image sensor 1, the method further comprises:

[0149] Encapsulating the image sensor 1 and the light filtering layer 2 in the shell 3.

[0150] It can be understood that after the image sensor 1 and the light filtering layer 2 are encapsulated together after the image sensor 1 and the light filtering layer 2 are formed on the light sensing path of the image sensor 1, a multispectral chip assembly is formed, and the integration of the multispectral chip is improved.

[0151] In an embodiment of the present application, the step of forming the light filtering layer 2 on the light sensing path of the image sensor 1 comprises:

[0152] Stacking the light filtering layer 2 at the light sensing lens of the image sensor 1.

[0153] It can be understood that the image sensor 1 is photosensitive through the light sensing lens, and the light filtering layer 2 is stacked at the light sensing lens of the image sensor 1, so that the light filtering layer 2 is located on the light sensing path of the image sensor 1, and the light filtering layer 2 can filter the light entering the image sensor 1, thereby increasing the number of channels that the image sensor 1 can realize.

[0154] In some examples, the step of obtaining the image sensor 1 comprises:

[0155] Obtaining the image sensor 1 based on a CSP packaging process.

[0156] In some examples, the step of obtaining the image sensor 1 comprises:

[0157] Obtaining the image sensor 1 based on a COB packaging process.

[0158] In some examples, the step of obtaining the image sensor 1 comprises:

[0159] Obtaining the image sensor in the form of a bare die.

[0160] According to the embodiment of the third aspect of the present application, the electronic device comprises the multispectral chip assembly described above.

[0161] According to the electronic device of the embodiment of the present application, by arranging the light filtering layer 2 on the light sensing path of the image sensor 1, the light will first pass through the light filtering layer 2 before entering the image sensor 1, the light filtering layer 2 can filter the light entering the image sensor 1, so that at least four different wave bands of light enter the image sensor 1. The wave band range of the light that can pass through the light filtering layer 2 is within the wave band range of the light that the image sensor 1 can obtain, which ensures that the image sensor 1 can normally image. That is, by arranging the light filtering layer 2 on the light sensing path of the image sensor 1, the light entering the image sensor 1 includes at least four different wave bands, at least four spectral channels can be realized, and the number of channels is increased, and multispectral imaging is realized.

[0162] The above describes the embodiments of the present application in detail, and the principles and implementation modes of the present application are described by applying specific examples. The above description of the embodiments is only used to help understand the method of the present application and its core idea; at the same time, for those skilled in the art, according to the idea of the present application, the specific implementation mode and application range will be changed, and the above description of the specification should not be understood as a limitation of the present application.

Claims

1. A method for fabricating a multispectral chip assembly, characterized in that, include: An image sensor is used to acquire light in different wavelength bands to obtain spectral information for each channel, wherein different channels correspond to spectral information in different wavelength bands. A filter layer is formed on the photosensitive path of the image sensor. The filter layer is used to filter the light entering the image sensor and allow light of at least four different wavelengths to pass through.

2. The method for fabricating a multispectral chip assembly according to claim 1, characterized in that, After the step of forming a filter layer on the photosensitive path of the image sensor, the method further includes: The image sensor and the filter layer are encapsulated within a housing.

3. The method for fabricating a multispectral chip assembly according to claim 1 or 2, characterized in that, The step of forming a filter layer on the photosensitive path of the image sensor includes: A filter layer is stacked on the photosensitive lens of the image sensor.

4. The method for fabricating a multispectral chip assembly according to claim 3, characterized in that, The steps for acquiring the image sensor include: Obtain an image sensor based on CSP packaging technology; or, Obtain an image sensor based on COB packaging technology; or, Acquire image sensors based on bare chip form.

5. The method for fabricating a multispectral chip assembly according to claim 1 or 2, characterized in that, The image sensor is an RGB image sensor.

6. A multispectral chip assembly, characterized in that, The multispectral chip assembly is prepared using the multispectral chip assembly preparation method as described in any one of claims 1 to 5.

7. The multispectral chip assembly according to claim 6, characterized in that, The multispectral chip assembly includes: An image sensor is used to acquire light in different wavelength bands to obtain spectral information for each channel, wherein different channels correspond to spectral information in different wavelength bands; A filter layer is disposed on the photosensitive path of the image sensor. The filter layer is used to filter the light entering the image sensor and allow light of at least four different wavelengths to pass through. The wavelength range of light that can pass through the filter layer is within the wavelength range of light that the image sensor can acquire.

8. The multispectral chip assembly according to claim 7, characterized in that, The multispectral chip assembly also includes a housing, in which the image sensor and the filter layer are encapsulated.

9. The multispectral chip assembly according to claim 8, characterized in that, Along the optical path direction of the filter layer, the orthographic projection of the image sensor on the bottom of the housing coincides with the orthographic projection of the filter layer on the bottom of the housing. or, Along the optical path direction of the filter layer, the orthographic projection of the image sensor on the bottom of the housing is within the orthographic projection of the filter layer on the bottom of the housing.

10. An electronic device, characterized in that, Includes the multispectral chip assembly as described in any one of claims 6 to 9.

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