CN117692802A - Image sensor, camera and electronic equipment - Google Patents

Abstract

The application discloses an image sensor, a camera and electronic equipment. The image sensor includes: a photosensitive cell array and a spectroscopic unit; the photosensitive unit array comprises a plurality of photosensitive units, and a gap is arranged on the first side of each photosensitive unit; the light splitting unit is arranged on the first surface of the photosensitive unit and covers the gap; the first surface is arranged adjacent to the surface of the first side of the photosensitive unit, and the first side of the light splitting unit is the side facing away from the photosensitive unit; the first optical signal incident from the first side of the light splitting unit is dispersed into second optical signals with different colors through the light splitting unit, the second optical signals are irradiated onto the photosensitive unit through the gap, and the photosensitive unit is used for respectively converting the second optical signals with each color into electric signals.

Description

Image sensor, camera and electronic equipment

Technical Field

The application relates to the technical field of electronic products, in particular to an image sensor, a camera and electronic equipment.

Background

With the trend of thinning and lightening intelligent electronic devices such as mobile phones, the size design of cameras is limited. The size of the image sensor is one of factors affecting the size of the camera, and in the design of the image sensor, the large number of pixels and the large pixel area are often not compatible. Specifically, under the condition that the size of the image sensor is fixed, the number of pixels needs to be increased to achieve higher resolution, and the size of a single pixel is reduced, so that the photosensitivity of the single pixel is reduced, and the imaging effect in a dark light environment is affected. For example, an image sensor using Red Green Blue (RGB) bayer arrangement, since one pixel presents one color information, a larger number of pixel points need to be set to ensure imaging effect, so that the requirement of small size cannot be met, and RGB three-color synthesis is required, which leads to higher false color. The image sensor adopting the pixel stacking structure utilizes the principle that light with different wavelengths has different penetrating power, so that one pixel can present all RGB color information, the pixel area and the synthetic false color can be reduced, but the light transmission in a medium has loss, and the light quantity received at the bottom layer of the pixel stacking structure is attenuated, thereby causing poor color reduction degree.

Disclosure of Invention

The embodiment of the application provides an image sensor, a camera and electronic equipment, so as to solve the problem that the image sensor in the prior art is poor in color reduction degree.

In order to solve the technical problems, the application is realized as follows:

in a first aspect, an embodiment of the present application provides an image sensor, including: a photosensitive cell array and a spectroscopic unit;

the photosensitive unit array comprises a plurality of photosensitive units, and a gap is arranged on the first side of each photosensitive unit; the light splitting unit is arranged on the first surface of the photosensitive unit and covers the gap;

a first optical signal incident from a first side of the light splitting unit is dispersed into second optical signals with different colors through the light splitting unit, the second optical signals are irradiated onto the photosensitive unit through the gap, and the photosensitive unit is used for respectively converting the second optical signals with each color into electric signals;

the first surface is adjacent to the surface of the first side of the photosensitive unit, and the first side of the light splitting unit is the side facing away from the photosensitive unit.

In a second aspect, embodiments of the present application provide a camera, including an image sensor as described above.

In a third aspect, embodiments of the present application provide an electronic device including a camera as described above.

Like this, among the above-mentioned scheme of this application, set up the clearance respectively at the first side of every sensitization unit in sensitization unit array, and pass through the beam splitting unit is dispersed the first optical signal of incidence into the second optical signal of different colours, makes the second optical signal propagate in the clearance and shine on the sensitization unit, carries out the photoelectric conversion of different colours optical signal, can avoid light to need penetrate the sensitization unit bottom and pass through the sensitization unit again and carry out the light quantity decay problem of photoelectric conversion, thereby guarantee that this image sensor can have higher color rendition.

Drawings

FIG. 1 shows a schematic diagram of a conventional structure CMOS image sensor;

FIG. 2 is a schematic diagram showing the arrangement of a color filter array in a CMOS image sensor of conventional construction;

FIG. 3 shows a schematic diagram of a CMOS image sensor with a pixel stack structure;

FIG. 4 shows one of the schematic diagrams of an image sensor of an embodiment of the present application;

fig. 5 shows a schematic diagram of a spectroscopic unit according to an embodiment of the present application;

FIG. 6 shows a second schematic diagram of an image sensor according to an embodiment of the present application;

FIG. 7 shows a schematic view of an optical path of an embodiment of the present application;

FIG. 8 is a schematic diagram of a pixel circuit according to an embodiment of the present application;

fig. 9 shows a circuit schematic of an image sensor according to an embodiment of the present application.

Detailed Description

Exemplary embodiments of the present application will be described in more detail below with reference to the accompanying drawings. While exemplary embodiments of the present application are shown in the drawings, it should be understood that the present application may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

The following description is made with respect to related arts in the art:

a Complementary Metal Oxide Semiconductor (CMOS) image sensor of a conventional structure is constituted by a microlens 111 (Micro lens), a color filter array 112 (Color filter array), a Photodiode 113 (photo diode), and the like, as shown in fig. 1.

The micro lens 111 is used for converging light, the color filter array 112 is used for filtering the incident light signals into light signals of three primary colors of red, green and blue, and the photodiode 113 is used for performing photoelectric conversion, namely, converting the light signals into electric signals.

Specifically, the color filter array 112 is composed of three filters of different colors arranged in the same spatial plane, and one filter of one color corresponds to one pixel (i.e., one filter of one color corresponds to one photodiode 113 of one color). Such a pixel may present a color information, i.e. a pixel may sense the intensity of a light signal of one of the three primary colors red, green, blue. Further, after the 4 pixels acquire the respective corresponding color information (because the human eye is more sensitive to green light, the number of G pixels can be set to be relatively large in the 4 pixels, for example, the 4 pixels can include an R pixel, two G pixels and a B pixel), and a color pixel is obtained through a "demosaicing" process and synthesis. As shown in fig. 2, a schematic diagram of a color filter array employing an RGB bayer arrangement is provided.

The CMOS image sensor of the pixel stack structure is constituted by a microlens 311, a photodiode 312, and the like. The CMOS image sensor of the pixel stack structure utilizes the principle that light with different wavelengths has different penetration forces (or penetration depths) (i.e., the longer the wavelength is, the greater the penetration depth is, for example, the penetration depth of red light > the penetration depth of green light > the penetration depth of blue light), i.e., the stacked arrangement of blue light sensors (blue sensors) or green light sensors (green sensors) or green light diodes 3122, red light sensors (red sensors) or red light photodiodes 3123 is performed at each pixel point from top to bottom, as shown in fig. 3.

Therefore, the CMOS image sensor with the pixel stacking structure can obtain the intensity of the light signals of three colors of true red, green and blue at each pixel point, so that algorithm filtering interpolation is not needed when the color information (namely RGB three-color synthesis) at the pixel point is restored, false colors can be reduced, and compared with the structure of the CMOS image sensor with the conventional structure, the CMOS image sensor with the pixel stacking structure has better resolution. However, the CMOS image sensor of the pixel stack structure causes poor color reproducibility due to the light amount decay of the photodiode of the bottom layer (i.e., the red photodiode 3123).

As shown in fig. 4, an embodiment of the present application provides an image sensor, including: a photosensitive cell array 1 and a spectroscopic unit 2.

The photosensitive cell array 1 comprises a plurality of photosensitive cells 10, and a gap is arranged on a first side of each photosensitive cell 10; the light splitting unit 2 is disposed on the first surface of the photosensitive unit 10 and covers the gap; wherein, the first surface is a surface adjacent to a surface of the first side of the photosensitive unit 10, and the first side of the light splitting unit 2 is a side facing away from the photosensitive unit 10.

The first optical signal incident from the first side of the light splitting unit 2 is dispersed into second optical signals of different colors by the light splitting unit 2, the second optical signals are irradiated onto the photosensitive unit 10 through the gap, and the photosensitive unit 10 is used for respectively converting the second optical signals of each color into electrical signals.

Specifically, in the case where the first optical signal is a complex color light, the light splitting unit 2 may disperse the first optical signal into a plurality of monochromatic lights with different colors, for example, the monochromatic light obtained by dispersion includes: at least one of red light, green light, blue light (i.e., the second light signal). The second optical signals obtained by dispersion are respectively irradiated onto the photosensitive units 10 in the gaps (as shown by arrow directions in fig. 4, which represent optical paths), so that the second optical signals with different colors can be respectively converted into corresponding electrical signals through photosensitive areas with different colors in the photosensitive units 10, and the problem of attenuation when light penetrates into the bottom layer of the photosensitive units 10 is avoided, thereby ensuring that the image sensor can have higher color reproducibility.

Alternatively, the light splitting unit 2 may be an integral structure, that is, the light sensing unit array 1 corresponds to one light splitting unit 2, and the light splitting unit 2 may disperse the incident first light signal into the second light signals with different colors, and irradiate the second light signals to each of the light sensing units 10 through the gaps, respectively. Alternatively, the light splitting unit 2 may include a plurality of light splitting sub-units, where the plurality of light splitting sub-units are disposed in a one-to-one correspondence with the plurality of photosensitive units 10, and each light splitting sub-unit may disperse the incident first optical signal into a second optical signal with a different color, and irradiate the second optical signal onto the corresponding photosensitive unit 10 through the gap, which is not limited in this embodiment.

In the above scheme, gaps are respectively arranged on the first side of each photosensitive unit 10 in the photosensitive unit array 1, and the light splitting unit 2 disperses the incident first optical signal into the second optical signals with different colors, so that the second optical signals propagate in the gaps and irradiate onto the photosensitive units 10 to perform photoelectric conversion on the optical signals with different colors, and the problem that light rays need to penetrate into the bottom layer of the photosensitive unit 10 and then pass through the photosensitive unit to perform photoelectric conversion is avoided, thereby ensuring that the image sensor can have higher color reduction degree.

Optionally, the photosensitive unit 10 includes: a plurality of photosensitive elements stacked in a first direction, each of the photosensitive elements for converting a second optical signal of one color into an electrical signal; wherein the first direction is a direction from a first surface to a second surface of the photosensitive unit 10, and the first surface is disposed opposite to the second surface.

For example, taking the side of the light splitting unit 2 as the upper side of the light sensing unit 10, a plurality of light sensing elements in the light sensing unit 10 are stacked from top to bottom, so that the second light signals of different colors obtained by the dispersion of the light splitting unit 2 can be irradiated onto each light sensing element from the side of the light sensing unit 10 in the gap, the light quantity received by each light sensing element is ensured to be consistent as much as possible, and the problem of attenuation of the light quantity received by the bottom light sensing element caused by the fact that light needs to penetrate into the bottom layer of the light sensing unit 10 to be irradiated onto each light sensing element is avoided, thereby ensuring that the image sensor can have higher color reproducibility.

Alternatively, the number of the plurality of photosensitive elements included in each photosensitive unit 10 may be 2 or 3, and different photosensitive elements are used to convert light signals of different colors into electrical signals. For example: when the number of the plurality of photosensitive elements is 2, that is, two color information (such as any two of red, green and blue) can be collected in one pixel, and the color information of at least two pixel points is synthesized to obtain a color pixel.

Also for example: when the number of the plurality of photosensitive elements is 3, that is, the photosensitive unit 10 includes: a first photosensitive element 101 for converting an optical signal of a first color into an electrical signal, a second photosensitive element 102 for converting an optical signal of a second color into an electrical signal, and a third photosensitive element 103 for converting an optical signal of a third color into an electrical signal.

The light splitting unit 2 is disposed on the first photosensitive element 101, the first photosensitive element 101 is disposed on the second photosensitive element 102, and the second photosensitive element 102 is disposed on the third photosensitive element 103; wherein the first color, the second color and the third color are each one of red, green and blue, and the first color, the second color and the third color are all different.

Here, the first photosensitive element 101, the second photosensitive element 102, and the third photosensitive element 103 are used to convert light signals of three primary colors (i.e., red light, green light, and blue light) into electrical signals, and one photosensitive element is used to convert light of one color into electrical signals, and specific red light, green light, and blue light each correspond to one photosensitive element, and the arrangement order in the photosensitive unit 10 is not specifically limited. Such as one implementation: the light sensing elements corresponding to the blue light, the green light and the red light respectively can be stacked from top to bottom, namely one implementation mode is as follows: the first color is blue, the second color is green, and the third color is red, however, in the embodiment of the present application, the stacking order of the photosensitive elements corresponding to each of the red light, the green light, and the blue light is not limited thereto.

Alternatively, as one implementation: a plurality of inclined structures 20 are arranged on the first side of the light splitting unit 2, and the inclined structures 20 are provided with inclined planes which are obliquely arranged relative to the first surface; wherein a first optical signal incident from a first side of the light splitting unit 2 is irradiated onto the inclined plane, and is dispersed into a second optical signal of a different color by the light splitting unit 2.

For example: in the case that the light splitting unit 2 is a unitary structure, the light splitting unit 2 may be formed by periodically arranging a plurality of inclined structures 20, for example: the plurality of inclined structures 20 in one arrangement period are disposed corresponding to one photosensitive unit 10. Alternatively, in the case that the light splitting unit 2 includes a plurality of light splitting sub-units, each of the light splitting sub-units is disposed corresponding to one of the photosensitive units 10 and includes a plurality of inclined structures 20.

Optionally, as yet another implementation: the spectroscopic unit 2 may be constituted by a spectroscopic grating. For example: in the case that the light splitting unit 2 is of an integral structure, the light splitting unit 2 may be formed by a light splitting grating, that is, the light splitting grating is disposed corresponding to the photosensitive unit array 1, and the light splitting grating may disperse the incident first optical signal into the second optical signals of different colors, and irradiate the second optical signals onto each of the photosensitive units 10 through the gaps, respectively.

Also for example: in the case where the spectroscopic unit 2 includes a plurality of spectroscopic sub-units, the spectroscopic unit 2 includes a plurality of spectroscopic gratings, that is, the spectroscopic unit 2 is constituted of a plurality of spectroscopic gratings. The plurality of light splitting gratings are arranged in a one-to-one correspondence with the plurality of light sensing units 10, that is, one light splitting subunit is formed by one light splitting grating, and one light splitting grating corresponds to one light sensing unit 10.

Alternatively, in the case where the spectroscopic unit 2 is constituted by one spectroscopic grating, the spectroscopic grating may be constituted by a plurality of inclined structures 20 arranged periodically, and the plurality of inclined structures 20 in one period correspond to one photosensitive unit 10. Alternatively, in the case where the spectroscopic unit 2 is constituted by a plurality of spectroscopic gratings, each of the spectroscopic gratings is constituted by a plurality of inclined structures 20.

Optionally, the light-splitting grating is a blazed grating. For example: the light splitting unit 2 is formed by a light splitting grating, that is, the light splitting unit 2 is formed by a blazed grating, and the blazed grating is disposed corresponding to the photosensitive unit array 1, and the blazed grating can disperse the incident first optical signal into the second optical signals with different colors, and irradiate the second optical signals onto each of the photosensitive units 10 through the gaps, respectively. Also for example: the light splitting unit 2 is formed by a plurality of light splitting gratings, that is, the light splitting unit 2 is formed by a plurality of blazed gratings, and each blazed grating of the plurality of blazed gratings is respectively corresponding to one photosensitive unit 10.

It should be noted that, in addition to the above implementation manner, the light splitting unit 2 in the embodiment of the present application may also use a micro-nano structure array, or a photonic crystal array, etc., which is not limited to this embodiment of the present application.

Alternatively, in order to ensure that the second optical signals of different colors emitted by the light splitting unit 2 can be respectively irradiated onto the photosensitive elements of the corresponding colors in the photosensitive unit 10 through the gaps, the structural parameters of the light splitting unit 2 need to be designed.

For example: in the case where the spectroscopic unit 2 is constituted by a plurality of inclined structures 20, it is necessary to design structural parameters of the inclined structures 20 including: the angle of inclination and the width of the inclined plane in the inclined structure 20, wherein the width of the inclined plane may be the distance from the lowest position of the inclined plane of one inclined structure 20 to the lowest position of the inclined plane of the next inclined structure 20, or the distance from the highest position of the inclined plane of one inclined structure 20 to the highest position of the inclined plane of the next inclined structure 20. As shown in fig. 5, the inclined surface of the inclined structure 20 has an inclination angle a and a width b.

Also for example: in case the light splitting unit 2 is constituted by one or more blazed gratings, the structural parameters that need to be designed for the tilted structure 20 include: the inclination angle of the saw-tooth wire groove section in the blazed grating and the broken width of the saw-tooth wire groove.

Optionally, the inclination angle of the inclined plane with respect to the first surface (or the inclination angle of the saw-tooth line groove cross-section in the blazed grating) and/or the width of the inclined structure 20 (or the saw-tooth line groove width) is determined by the angle of incidence of the second optical signal onto the photosensitive unit 10.

For example: based on the above structure of the light splitting unit, consider that the light outgoing angle of the position with the maximum energy of the first optical signal passing through the light splitting unit 2 will present a certain included angle with the incident angle of the light, and the included angles corresponding to different wavelengths are different. Since the light emission angles of the light signals with different wavelengths at the position of the maximum energy of the light splitting unit 2 are different, the light splitting unit 2 realizes that the first light signals are dispersed into the second light signals with different colors, and the second light signals with different colors are emitted from the light splitting unit 2 at different light emission angles. In this way, when the structural parameters of the light splitting unit 2 are designed, the light emission angle of the second optical signal emitted from the light splitting unit 2 (or the light emission angle of the second optical signal emitted from the light splitting unit 2 may be determined by simulating the optical path when the second optical signal propagates in the gap and irradiates the corresponding light splitting unit) may be determined according to the width of the gap, the distance between each light sensing element and the light splitting unit, etc., and the inclination angle of the inclined plane with respect to the first surface (or the inclination angle of the saw-tooth line groove section in the blazed grating) and/or the width of the inclined structure 20 may be designed according to the incident angle of the second optical signal irradiating the light sensing unit 10.

Specifically, taking the example that the light splitting unit 2 is configured to disperse the incident first optical signal into the second optical signal of three primary colors of red, green and blue, by presetting the inclination angle of the inclined plane relative to the first surface (or the inclination angle of the saw-tooth line slot section in the blazed grating) and/or the width of the inclined structure 20 in the light splitting unit 2, the incident direction and angle of the light when the second optical signal of three primary colors of red, green and blue irradiates the photosensitive element can be controlled. With continued reference to fig. 5, the light splitting unit 2 is composed of periodic inclined planes (or saw-tooth line groove sections in blazed gratings), the width of the inclined planes (i.e. the width of the inclined structure 20) is d, and the inclination angle of the inclined planes is a (where the value ranges of d and a may be determined according to specific design results). Based on the optical principle, the following relation is satisfied in the spectroscopic unit:

d*(sin i+siny)＝m*l

where i is an incident angle (i is related to the inclination angle) of the light beam irradiated onto the light-splitting unit, y is an exit angle of the light beam when the light beam exits from the light-splitting unit, l is a wavelength of the light beam, and m is a spectrum order of the wavelength. Based on the above formula, when d, i, and m are identical, the y values are different (i.e., the corresponding light exit angles are different) for the light rays with different wavelengths. Therefore, the inclination angle in the light splitting unit 2 and/or the width of the inclined structure 20 may be designed according to the incidence angle (i.e. the exit angle when the light is emitted from the light splitting unit) of the second light signal to be irradiated to the light sensing unit 10.

Optionally, as shown in fig. 6 and 7, the photosensitive cell array 1 further includes: a reflector 11 disposed in each of the gaps; wherein the second light signal is reflected to the photosensitive unit 10 by the reflector 11.

For example: the arrow direction in fig. 7 indicates the optical path propagation direction when the reflector 11 is provided. The second light signals of different colors emitted from the light-splitting unit 2 based on the above analysis have different light exit angles, so that these second light signals of different colors also have different light incident angles when they are irradiated onto the reflector 11. Based on the principle of light reflection: the incident angle of the light is the same as the emergent angle of the light, and the second light signals with different colors can irradiate the photosensitive elements with different incident angles, so that the second light signals with different colors can be ensured to irradiate the photosensitive elements with corresponding colors, and the photoelectric conversion of the light signals with different colors is realized.

In this embodiment, the reflector 11 is arranged in the photosensitive unit array 1, so that the second light signals with different colors can be irradiated on the photosensitive elements with corresponding colors, thereby ensuring that the image sensor completes the collection of the light signals.

Alternatively, the reflector 11 in the first gap is disposed on the surface of the second side of the photosensitive unit 10; wherein the first gap is a gap between two photosensitive units 10, and the first side and the second side of the photosensitive units 10 are opposite to each other.

With continued reference to fig. 6, the two photosensitive units 10 include: the first side of the photosensitive unit A and the second side of the photosensitive unit B are provided with gaps, and the second side of the photosensitive unit B is provided with the reflector 11. So that the second light signals of different colors emitted through the light-splitting unit 2 can pass through the gap and impinge on the reflector 11 of the light-sensing unit B at different angles of incidence. Based on the light reflection principle, the reflector 11 can reflect the second light signals with different colors into the corresponding color photosensitive units in the photosensitive units A respectively so as to realize photoelectric conversion of the light signals with different colors.

In the embodiment of the application, the image sensor not only has the advantage of the stacked pixel structure image sensor, but also can obtain the color information of three colors of red, green and blue of a real pixel point at each pixel position, and the light splitting unit is arranged on the light sensing unit array, so that the problem of energy attenuation of light transmitted in the light sensing unit is solved, the problem of reduced color reduction performance caused by light incoming quantity attenuation of a bottom layer light sensing element in the stacked pixel structure image sensor is avoided, the image sensor can be ensured to better complete color information collection of the real pixel point, and color reduction is accurately carried out, so that the truest image is restored.

As shown in fig. 8, a schematic diagram of a pixel circuit is given. A pixel circuit array composed of a plurality of pixel circuits (pixels) may be used to construct an image sensor circuit, as shown in fig. 9, and a pixel circuit array composed of a plurality of pixel circuits 90 is connected to a digital-to-Analog converter (ADC) through an amplifier 91, where RST is a transistor reset tube.

The pixel circuit employs a 4-pixel structure (4 trans, 4 t), or a pixel (Pinned Photodiode Pixel, PPD) structure called a clamp photodiode. The PPD structure includes a photosensitive area PPD (i.e., a photosensitive diode), and a photosensitive area PPD transistor, a reset tube RST, a switch TG, a row selector SEL, and a signal amplifier SF, where VDD represents a power supply voltage and L represents a column bus.

The PPD structure works as follows:

1. exposure process: electron-hole pairs generated by light signals irradiated onto the photosensitive region PPD are separated due to the influence of an electric field of the PPD structure, i.e., electrons move to the N region of the photodiode and holes move to the P region of the photodiode.

2. Resetting: at the end of the exposure process, the transistor reset tube RST is activated (or called enabled) to reset the N-region of the photodiode to a high level.

3. Reset level read-out process: after the reset process is completed, the reset level is read out and the read signal is stored in the first capacitor. The read reset level includes offset (offset) noise, 1/f noise (or referred to as flicker noise or low-frequency noise) of the signal amplifier SF, and kTC noise (kTC noise is output noise of bandwidth thermal noise caused by electronic thermal motion and reflected on a junction capacitor after being filtered by a PN junction, the noise power is represented by kT/C, k represents a boltzmann constant, T represents a PN junction temperature, C represents a junction capacitor, and three physical quantities of k, T and C jointly determine the magnitude of noise power spectral density in kTC noise).

4. Charge transfer process: the transistor of the photosensitive region PPD is activated (or called enabled) to transfer the Charge completely to the N region for readout, and the mechanism here is similar to Charge transfer in a Charge-Coupled Device (CCD), and will not be described again here.

5. Signal level readout process: the voltage signal of the N area is read out to the second capacitor. The voltage signal here comprises: the signals generated by photoelectric conversion, offset noise generated by the signal amplifier SF, 1/f noise, and kTC noise introduced by reset.

6. The signal output process comprises the following steps: the signals stored in the two capacitors are subtracted (for example, a correlated double sampling circuit (Correlated Double Sampling, CDS) is adopted, so that main noise in the pixel circuit can be eliminated), and the obtained signals are subjected to analog amplification and ADC sampling, so that digitized signal output can be carried out.

The embodiment of the application also provides a camera, which comprises the image sensor.

Optionally, the camera may include, in addition to the image sensor, at least one of the following: lens, voice coil motor, infrared Filter (IR Filter), etc., the embodiment of the present application is not limited thereto.

The embodiment of the application also provides electronic equipment, which comprises the camera.

Optionally, the electronic device may be a device configured with the camera, such as a mobile phone, a tablet computer, a wearable device, a notebook computer, etc., which is not limited in this embodiment.

In this specification, each embodiment is described in a progressive manner, and each embodiment is mainly described by differences from other embodiments, and identical and similar parts between the embodiments are all enough to be referred to each other.

While preferred embodiments of the present embodiments have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. It is therefore intended that the following claims be interpreted as including the preferred embodiments and all such alterations and modifications as fall within the scope of the embodiments of the present application.

Finally, it is further noted that relational terms such as first and second, and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or terminal that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or terminal. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a process, method, article or terminal device comprising the element.

While the foregoing is directed to the preferred embodiments of the present application, it should be noted that modifications and adaptations to those embodiments may be made by one of ordinary skill in the art without departing from the principles set forth herein and are intended to be within the scope of the present application.

Claims (11)

1. An image sensor, comprising: a photosensitive cell array and a spectroscopic unit;

the photosensitive unit array comprises a plurality of photosensitive units, and a gap is arranged on the first side of each photosensitive unit; the light splitting unit is arranged on the first surface of the photosensitive unit and covers the gap;

a first optical signal incident from a first side of the light splitting unit is dispersed into second optical signals with different colors through the light splitting unit, the second optical signals are irradiated onto the photosensitive unit through the gap, and the photosensitive unit is used for respectively converting the second optical signals with each color into electric signals;

the first surface is adjacent to the surface of the first side of the photosensitive unit, and the first side of the light splitting unit is the side facing away from the photosensitive unit.

2. The image sensor of claim 1, wherein the photosensitive unit comprises: a plurality of photosensitive elements stacked in a first direction, each of the photosensitive elements for converting a second optical signal of one color into an electrical signal;

the first direction is a direction from a first surface to a second surface of the photosensitive unit, and the first surface and the second surface are opposite to each other.

3. The image sensor according to claim 1 or 2, wherein the photosensitive unit includes: a first photosensitive element for converting an optical signal of a first color into an electrical signal, a second photosensitive element for converting an optical signal of a second color into an electrical signal, and a third photosensitive element for converting an optical signal of a third color into an electrical signal;

the light splitting unit is arranged on the first photosensitive element, the first photosensitive element is arranged on the second photosensitive element, and the second photosensitive element is arranged on the third photosensitive element;

wherein the first color, the second color and the third color are each one of red, green and blue, and the first color, the second color and the third color are all different.

4. The image sensor of claim 1, wherein a first side of the light splitting unit is provided with a plurality of inclined structures having inclined surfaces disposed obliquely with respect to the first surface;

the first optical signal incident from the first side of the light-splitting unit irradiates the inclined plane, and is dispersed into the second optical signal with different colors through the light-splitting unit.

5. The image sensor of claim 4, wherein an angle of inclination of the inclined surface with respect to the first surface and/or a width of the inclined structure is determined according to an angle of incidence of the second light signal to the light sensing unit.

6. The image sensor of claim 1, wherein the array of photosensitive cells further comprises: a reflector disposed within each of the gaps;

the second optical signal is reflected to the photosensitive unit through the reflector.

7. The image sensor of claim 6, wherein the reflector in the first gap is disposed on a surface of the second side of the photosensitive cell;

the first gap is a gap between two photosensitive units, and the first side and the second side of the photosensitive units are arranged opposite to each other.

8. The image sensor of claim 1, wherein the light-splitting unit includes a plurality of light-splitting gratings, and the plurality of light-splitting gratings are disposed in one-to-one correspondence with the plurality of light-sensing units.

9. The image sensor of claim 8, wherein the spectral grating is a blazed grating.

10. A camera comprising the image sensor of any one of claims 1 to 9.

11. An electronic device comprising the camera of claim 10.