CN111988499B

CN111988499B - Imaging layer, imaging device, electronic apparatus, wave zone plate structure and photosensitive pixel

Info

Publication number: CN111988499B
Application number: CN201911243858.XA
Authority: CN
Inventors: 王曙光; 蔡闹闹
Original assignee: Vkansee Beijing Technology Co ltd
Current assignee: Weinan Impression Cognitive Technology Co ltd
Priority date: 2019-05-22
Filing date: 2019-12-06
Publication date: 2022-03-15
Anticipated expiration: 2039-12-06
Also published as: TW202107065A; CN111988499A; WO2020233601A1

Abstract

The application discloses formation of image layer, imaging device, electronic equipment, wave zone plate structure and sensitization pixel, include the formation of image layer and be located the image sensor of formation of image layer downside, be equipped with a plurality of formation of image hole on the formation of image layer, every be equipped with the wave zone plate structure in the formation of image hole, the wave zone plate structure is including shading area and printing opacity area, the wave zone plate structure makes the light of reflection through the target assemble in image sensor is last to form images. The wave zone plate structure is arranged on the imaging layer and is calculated and designed according to the principle of light interference, so that monochromatic light passing through the light-transmitting zone is coherently enhanced and converged on the image sensor, further, the light converged on the image sensor is coherent enhanced light, and the light intensity is greatly amplified. Meanwhile, since the light transmission area is increased, the relative height of the secondary peak of interference/diffraction generated by the fluctuation of light and the distance from the primary peak are also decreased. Thereby further improving optical resolution.

Description

Imaging layer, imaging device, electronic apparatus, wave zone plate structure and photosensitive pixel

This application claims priority to a chinese patent application filed by the chinese bureau of china on 22/5/2019 and having application number 201910430939.4, the entire contents of which are incorporated herein by reference.

Technical Field

The application relates to the technical field of image acquisition, in particular to an imaging device. In addition, the application also relates to an imaging layer, electronic equipment, a zone plate structure and a photosensitive pixel.

Background

The existing mobile terminal, such as a mobile phone and the like, hopes to achieve a comprehensive screen design, and integrates fingerprint identification and a front camera under a display screen without influencing display. In the prior art, there is a technology of integrating fingerprint recognition under a display screen, for example, in the prior patent CN201710086890.6, a Matrix Pinhole Imaging System (MAPIS) is proposed for collecting surface images of an object at a short distance, such as fingerprint images and face images. The MAPI can be applied to various electronic devices such as mobile phones, tablet computers and smart bands.

MAPIS generally includes an orifice plate and an image sensor. The small pore plate is provided with a plurality of imaging holes. The image sensor is disposed at one side of the aperture plate and corresponds to a position of the imaging aperture. Thus, according to the pinhole imaging principle, light on the target on the other side of the pinhole plate can pass through the imaging hole to form an inverted image of the target on the image sensor. The light passing through each imaging aperture can form a corresponding image on the image sensor, and the images can be spliced to obtain a relatively complete image of the target object.

The MAPI can be applied to electronic equipment with a display screen to acquire fingerprint images, human face images and the like. A display screen of an electronic device includes light emitting pixels arranged in an array, and a circuit for controlling the light emitting pixels. The circuits are typically opaque but have gaps between them so that light above the display can pass through the gaps to below the display. The small hole plate is arranged below the display screen, and the area through which light can pass is specified through the position, size and shape of the imaging hole in the small hole plate. The imaging aperture on an ideal aperture plate is about 10-15 μm. At the moment, the light intensity through the imaging hole is proper, the diffraction is small, the definition of an image formed on the image sensor is high, the resolution is good, and the requirement of the electronic equipment with the display screen can be met.

However, as the resolution of the display screen is higher and higher, the arrangement of the light-emitting pixels is tighter and tighter, and the number of corresponding circuits is also higher, which results in a great reduction of the gap between the circuits (for example, to about 5 μm), and it is difficult to achieve the requirement of the ideal aperture of the imaging aperture. In the case where the aperture of the imaging aperture is greatly reduced due to the limitation of the gap, the intensity of light passing through the imaging aperture is reduced, and diffraction is severe, which in turn causes the light to be difficult to be received by the image sensor and easily drowned in the thermal noise of the image sensor.

On the other hand, a scheme that a front-facing camera is integrated under a display screen and display is not affected does not exist in the prior art. The closest scheme is that a lifting camera, a water drop frame, a display screen and the like are provided with holes. But both of the latter have an effect on the display.

In patent 201811271636.4 (application number, not yet published, having the utility model applied on the same day), a scheme of an under-screen camera is proposed. This solution also requires a relatively large central hole and is used with a lens. The thickness of the lens can hinder assembly, as the lens needs to be placed under the display screen.

Disclosure of Invention

The present application provides an imaging layer, an imaging device using the imaging layer, and an electronic apparatus, which solve the above technical problems by making full use of interference enhancement characteristics of light.

In a first aspect, the present application provides an imaging device, include the formation of image layer and be located the image sensor of formation of image layer downside, be equipped with a plurality of formation of image hole on the formation of image layer, every be equipped with the zone plate structure in the formation of image hole, the zone plate structure includes shading band and printing opacity area, the zone plate structure make through the light of target reflection assemble in image sensor goes up the formation of image.

With reference to the first aspect, in a first possible implementation manner of the first aspect, when a sum of areas of transparent bands of the zone plate structure in the imaging hole is greater than a sum of areas of opaque bands, the opaque bands are removed. In a second aspect, the present application provides an electronic device comprising the imaging device and a display screen, wherein the display screen comprises a circuit layer;

when the circuit layer comprises a plurality of first light-transmitting parts, a plurality of imaging holes are formed in the imaging layer, a zone plate structure is arranged in each imaging hole, and each imaging hole corresponds to the corresponding first light-transmitting part; the area of the first light transmitting portion is sufficient to provide at least one zone plate structure.

In a third aspect, the present application provides an electronic device comprising a display screen, an imaging layer, and an image sensor;

the display screen comprises a circuit layer, wherein the circuit layer comprises a plurality of second light-transmitting parts;

the imaging layer is positioned below or above the circuit layer;

the imaging layer comprises a plurality of imaging holes, zone plate structures are arranged in the imaging holes, the imaging layer is aligned with the circuit layer, a light transmission belt of the imaging layer is enabled to be superposed with second light transmission parts of the circuit layer, and one zone plate structure corresponds to a plurality of second light transmission parts;

wherein the zone plate structure comprises a shading band and a transmitting band; when the target object contacts the display screen, after the target object reflects, the incident light rays pass through the light-transmitting part and the light-transmitting belt and are converged on the image sensor to form an image.

With reference to the third aspect, in a first possible implementation manner of the first aspect, when at least two imaging holes are formed in the imaging layer, image space fields of adjacent imaging holes do not coincide.

With reference to the third aspect and the foregoing possible implementation manners, in a second possible implementation manner of the first aspect, when at least two imaging holes are formed in the imaging layer, object-side fields of view of adjacent imaging holes are overlapped.

With reference to the third aspect and the foregoing possible implementations, in a third possible implementation of the first aspect, the number of the imaging holes is 3.

With reference to the third aspect and the foregoing possible implementation manners, in a fourth possible implementation manner of the first aspect, the circuit layer further includes light-emitting pixels arranged in an array, the number of the light-emitting pixels in a unit area is reduced, a plurality of imaging holes are formed in an imaging layer corresponding to a missing light-emitting pixel, and a zone plate structure is arranged in each imaging hole.

With reference to the third aspect and the foregoing possible implementation manners, in a fifth possible implementation manner of the first aspect, at least one light-emitting pixel is spaced between two adjacent light-emitting pixels that are missing.

With reference to the third aspect and the foregoing possible implementation manners, in a sixth possible implementation manner of the first aspect, a distance between the image sensor and the imaging layer is set to meet a requirement that light emitted from a point on the object plane is converged at a point on the image sensor.

With reference to the third aspect and the foregoing possible implementation manners, in a seventh possible implementation manner of the third aspect, the imaging hole and the light-transmitting band of the zone plate structure are further used for a through hole for routing a circuit line.

With reference to the third aspect and the foregoing possible implementation manners, in an eighth possible implementation manner of the third aspect, the imaging layer is aligned with the circuit layer, so that a maximum overlapping area or an overlapping area of the light-transmitting strip of the imaging layer and the second light-transmitting portion of the circuit layer satisfies a preset area threshold range.

In a fourth aspect, the present application provides an imaging device comprising the imaging layer of the third aspect.

In a fifth aspect, the present application provides an electronic device comprising a display screen, an imaging layer, and an image sensor;

the display screen comprises a circuit layer, wherein the circuit layer comprises a plurality of light-transmitting parts;

the imaging layer is positioned below the circuit layer;

at least three image sensors are arranged below the imaging layer and are respectively used for receiving red light, green light and blue light;

the imaging layer is provided with a zone plate structure corresponding to each image sensor, and the zone plate structure comprises a shading zone and a light-transmitting zone;

when the target object outside the display screen emits light, the zone plate structure corresponding to each image sensor enables the light with the corresponding wavelength to be converged on the corresponding image sensor, and a color image is formed through the image processing module.

In a sixth aspect, the present application provides an imaging layer comprising a light blocking portion and a light transmitting portion arranged by circuit lines, wherein the light transmitting portion focuses light reflected by a target onto an image sensor for imaging.

In a seventh aspect, the present application provides an imaging layer, where a zone plate structure is disposed on the imaging layer, the zone plate structure includes a first zone plate and a second zone plate that have the same structure, and the first zone plate and the second zone plate are disposed up and down, so that light rays in a connecting line direction between central points of the first zone plate and the second zone plate can pass through the first zone plate and the second zone plate and form an image.

In an eighth aspect, the present application provides an imaging layer comprising a zone plate structure, the zone plate structure comprising a light-blocking zone and a light-transmitting zone, the imaging layer being made of a conductive material.

With reference to the eighth aspect, in a first possible implementation manner of the eighth aspect, the shading strips are communicated with each other through a connecting member, and the connecting member is made of a conductive material.

With reference to the eighth aspect, in a second possible implementation manner of the eighth aspect, the imaging layer is further configured to supply power.

In a ninth aspect, the present application provides a tilted zone plate structure obtained by a method comprising:

placing a positive wave band plate structure on a normal plane of incident light, wherein the positive wave band plate structure is orthogonal to an incident optical axis, and the incident angle of the incident light is theta;

and taking the intersection point of the focal plane of the positive wave band plate structure and the optical axis of the incident light as a center, and carrying out central projection on the positive wave band plate structure, wherein the projection falling on the plane of the diffraction screen is an inclined wave band plate structure.

With reference to the first implementation manner of the eighth aspect, an inclined angle of the inclined zone plate structure is away from an incident direction of ambient light, and the inclined angle is that an incident angle of the incident light ray is θ.

In a tenth aspect, the present application provides a split-field imaging apparatus, including at least two imaging devices, each of the imaging devices including a zone plate structure, and an image sensor disposed below the zone plate structure, wherein each of the zone plate structures corresponds to one image sensor, or a plurality of the zone plate structures correspond to one image sensor; each zone plate structure is used for converging object space field rays to the corresponding image sensor, wherein the corresponding inclined field rays are matched with the inclined zone plate structure.

In an eleventh aspect, the present application provides an imaging layer comprising the tilted zone plate structure.

In a twelfth aspect, the application provides a narrow-field photosensitive pixel, wherein a field diaphragm is arranged on the upper surface of the photosensitive pixel, and the zone plate structure is arranged above the field diaphragm; the zone plate structure comprises a shading zone and a light transmission zone, and the zone plate structure enables light rays reflected by a target object to be converged on the image sensor for imaging;

the object surface is positioned in a set area above the photosensitive pixel, and the image surface of the object surface is positioned on the plane of the field diaphragm; the zone plate structure and the field diaphragm enable the photosensitive pixel to have an object space field with a limited field angle on the object plane of the set area; the image point or the image spot of the object point in the object space field falls in the small hole of the field diaphragm; and the image point or the image spot of the object point positioned outside the object space field of view falls outside the small hole.

With reference to the first implementation manner of the tenth aspect, a light shielding wall is disposed between adjacent photosensitive pixels, and the light shielding wall is located on the upper side of the photosensitive pixels.

The imaging layer can be applied to electronic equipment, especially electronic equipment with a display screen, a zone plate structure is arranged on the imaging layer and is calculated and designed according to the principle of light interference, monochromatic light coherent enhancement passing through a light transmission band is converged on an image sensor, the shading band part is divided into a part which is subjected to coherent cancellation convergence of the calculated monochromatic light and is arranged on the image sensor, and then the light converged on the image sensor is coherent enhancement light, and the light intensity is greatly amplified. Meanwhile, since the light transmission area is increased, the relative height of the secondary peak of interference/diffraction generated by the fluctuation of light and the distance from the primary peak are also decreased. Thereby further improving optical resolution.

Drawings

In order to more clearly explain the technical solution of the present application, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious to those skilled in the art that other drawings can be obtained according to the drawings without any creative effort.

FIG. 1 is a prior art image path diagram of MAPI;

FIG. 2 is a top view of a prior art MAPI orifice plate;

FIG. 3 is a schematic diagram of an optical path of a converging light in one implementation of the imaging device of the present application;

FIG. 4 is a top view of an imaging layer in one implementation of an imaging device of the present application;

FIG. 5 is a top view of one circuit layer of the present application;

FIG. 6 is a schematic structural diagram of an implementation manner of an imaging device of the present application applied to an electronic device having a display screen;

FIG. 7A is a top view of another circuit layer of the present application;

FIG. 7B is a top view of another circuit layer of the present application;

FIG. 8A is a top view of an imaging layer of the present application corresponding to the circuit layer of FIG. 7A;

FIG. 8B is a top view of an imaging layer of the present application corresponding to the circuit layer of FIG. 7B;

FIG. 9 is a top view of an imaging layer of the present application corresponding to the circuit layer of FIG. 5;

fig. 10A is a schematic structural diagram of another implementation of the imaging apparatus of the present application applied to an electronic device having a display screen;

FIG. 10B is a schematic structural diagram of another implementation of the imaging apparatus of the present application in an electronic device having a display screen;

FIG. 11 is a schematic structural diagram illustrating another implementation of an imaging device applied in an electronic device having a display screen after reducing the number of light-emitting pixels per unit area according to the present application;

FIG. 12 is a top view of the corresponding imaging layer according to FIG. 11;

FIG. 13 is a schematic diagram of another embodiment of an imaging device of the present application implemented in an electronic device having a display screen;

FIG. 14A is a schematic structural diagram of another implementation of an imaging device of the present application in an electronic device having a display screen;

FIG. 14B is a schematic diagram of another embodiment of an imaging device of the present application implemented in an electronic device having a display screen;

FIG. 15 is a schematic diagram of one configuration of an inclined zone plate configuration of the present application;

FIG. 16 is another schematic structural view of the tilted zone plate structure of the present application;

FIG. 17 is a schematic design of the tilted zone plate structure of the present application;

FIG. 18 is a schematic diagram of one implementation of an inclined zone plate structure of the present application as applied to a fingerprint acquisition device;

FIG. 19 is a schematic optical path diagram of an application of the tilted zone plate structure of the present application in a fingerprint acquisition device;

fig. 20 is a schematic structural diagram of an implementation mode of applying the zone plate structure of the present application to a photosensitive pixel.

FIG. 21 is a schematic optical path diagram of one implementation of the present application with a bilayer imaging layer;

FIG. 22 is a schematic optical path diagram of another implementation of the present application with a bilayer imaging layer.

Detailed Description

The MAtrix type porous imaging (MAPI) device can be used for ultrathin optical fingerprint collection, fingerprint collection On a Display screen (FOD) and other occasions.

Referring to fig. 1 and 2, fig. 1 is an imaging optical path diagram of MAPIS, and fig. 2 is a top view of a MAPIS orifice plate, which generally includes an orifice plate 101 and an image sensor 102. The aperture plate 101 has a plurality of imaging holes. The image sensor 102 is disposed on one side of the orifice plate 101, and corresponds to the position of the imaging hole. Thus, according to the principle of pinhole imaging, light from the target on the other side of the pinhole plate 101 can pass through the imaging hole, and an inverted image of the target is formed on the image sensor 102. The light passing through each imaging aperture may form a corresponding image on the image sensor 102, and stitching the multiple images together may result in a relatively complete image of the object.

The MAPIS technique, however, suffers from some disadvantages as follows. For example: 1. for a pore diameter of 5 microns, the airy disk diameter was 1.22 x 400 x 0.55/5 x 53.68 microns over a distance of 400 microns for a green light of 0.55 microns according to the airy disk calculation formula. It can be seen that the diffraction spot of light passing through a small aperture of 5 microns is enlarged by a factor of about 10, and the area is correspondingly enlarged by a factor of one hundred, so that the light intensity is reduced by a factor of one hundred, which is very disadvantageous for imaging. In the case of a high resolution display screen, the diameter of the small holes may be further reduced, so that diffraction is more severe and energy is sharply attenuated. Therefore, when the aperture of the pinhole is too large, image blurring is caused, and when the aperture of the pinhole is small, energy is insufficient, resulting in both energy shortage and image blurring. 2. Some applications limit the use of small holes of suitable size. For example, when the MAPIS technology is applied to an OLED display screen, limited by a driving circuit in the OLED display screen, imaging pinholes can only be placed in light-transmitting gaps of a circuit network, and the shapes and sizes of the pinholes cannot be freely adjusted, so that the imaging energy of the pinholes is insufficient, and the performance is reduced.

On the other hand, even if a large aperture can be opened, the light intensity may be insufficient. This is because although the total amount of transmitted light increases as the aperture increases, the spot formed also increases, and thus the intensity per unit area does not increase.

In order to solve the problem, the application provides an imaging device which can be applied to electronic equipment, in particular to electronic equipment with a display screen, can be used for imaging a target object contacting the display screen or imaging the target object outside the display screen, and can fully utilize the interference enhancement characteristic of light. The object touching the display screen may be a fingerprint, a palm print, or the like.

The display screen includes a circuit layer 4, and usually the circuit layer 4 is arranged in a laminated and staggered manner, so that it is difficult to design a large-enough small hole, but many smaller small holes can be designed, as shown in fig. 5, a white area is a light-transmitting small hole of the circuit layer 4, and light rays can interfere with each other after passing through the small holes to form complex interference fringes, which is difficult to process. In past solutions, the largest of these small holes could be selected and the other small holes shielded. This reduces the disturbance but at the same time also the light intensity.

Carefully analysing the coherent interference between apertures, it has been found that, for a certain point on the image plane, generally, some of the apertures will interfere coherently, while another part of the apertures will interfere coherently, destructively. From the angle analysis of the optical path, the optical path from the light source to the small holes is not considered for the moment, the difference between the optical paths from a part of the small holes to a certain point on the image surface is integral multiple of the wavelength, and the light passing through the small holes is enhanced in coherence on the image surface; when the optical path length traveled by light passing through another part of the apertures differs from the optical path length traveled by light passing through the aforementioned apertures by a half-integer multiple of the wavelength, i.e., 0.5 times, 1.5 times, 2.5 times, etc., light rays whose optical path length differs by a half-integer multiple of the wavelength are coherently canceled with respect to the aforementioned apertures. Thus, an imaging layer 1 can be provided to block the coherence-canceling apertures, leaving only coherence-enhancing apertures, so that at this point on the image plane, the light rays are all coherence-enhancing and the light intensity is greatly enhanced. Thereby forming a zone plate structure composed of a light-shielding band and a light-transmitting band on the imaging layer 1. Due to coherent superposition, the amplitude of the light waves is directly superposed, and the intensity of the light is proportional to the square of the amplitude, so that finally the intensity of the point light is proportional to the square of the number of remaining pores. For example, if 10 apertures are retained, the spot will be one hundred times as intense as if only one aperture were retained, thus greatly increasing the intensity. Based on the above analysis, in a first embodiment of the present application, an electronic device is used for imaging an object contacting a display screen 5, such as: a fingerprint acquisition device for acquiring fingerprints through the display screen 5, referring to fig. 6, the electronic device includes: the display screen 5 and the imaging device, the imaging device includes imaging layer 1 and image sensor 2, imaging layer 1 is located above image sensor 2.

In this embodiment, the imaging layer 1 is a periodic imaging plate structure, and a plurality of light-shielding and light-transmitting portions are periodically provided thereon. The period may coincide with the pixel period.

The display screen 5 may comprise a light-emitting pixel layer and a circuit layer 4, and the imaging layer 1 is closely attached to the lower side or the upper side of the circuit layer 4, or the imaging layer 1 is formed by circuit line arrangement of the circuit layer 4 itself. When the imaging device is applied to an electronic apparatus having the display screen 5, the circuit layer 4 in the display screen 5 may be the same as or similar to the conventional arrangement, and at this time, there is still a gap in the circuit layer 4. Since light can pass through these gaps, these gaps may be collectively referred to as a light-transmitting portion of the circuit layer 4. The circuit layer 4 is typically arranged in a stacked, staggered design, and therefore the light-transmitting portion is also typically irregularly shaped, and for this purpose the imaging layer 1 is provided with a zone plate structure 3 that cooperates with the light-transmitting portion.

The zone plate structure 3 comprises a shading band and a light transmission band which are arranged at intervals, and the zone plate structure 3 is obtained by calculation design according to the principle of light interference, so that the overall effect of light rays passing through the zone plate structure 3 is enhanced. For example, when an imaging aperture in the imaging layer 1 is provided with a zone plate structure 3 including two light-transmitting bands and one light-shielding band, and the areas of the two light-transmitting bands are larger than the area of the one light-shielding band, the shielding of the light-shielding band can be canceled because the overall effect through the imaging aperture is coherently enhanced even if the light-shielding band is canceled.

In order to optimize the effect, all the calculated coherence enhancement parts can be retained to form a transmission band, and all the coherence cancellation parts can be shielded to form a shading band. The monochromatic light passing through the light transmission band is coherently enhanced and converged on the image sensor, and the shading band part is a part coherently and destructively converged with the image sensor by calculating the monochromatic light, so that the light converged on the image sensor is coherent enhanced light, and the light intensity is greatly amplified.

Because this application technical scheme has utilized undulant characteristics such as diffraction of light/interference, and the wave nature of light is relevant with the wavelength of light, thereby when carrying out fingerprint collection, display screen 5 sends monochromatic light, after monochromatic light passes through the printing opacity part of circuit layer 4 and the printing opacity area of formation of image layer 1 respectively after the finger 6 reflection with display screen 5 contact, because the diffraction of light and the interference of light assemble formation of image on image sensor, monochromatic light can be any kind of chromatic light in green glow, ruddiness and blue light. When the zone plate structure is designed, the positions of the shading zone and the light transmission zone of the corresponding zone plate structure 3 are different according to the different colors of the monochromatic light. Monochromatic light illumination is adopted, and the zone plate structure 3 only has a convergence effect on a certain monochromatic light, which is a great advantage. This means that the external interference light of other wavelengths cannot be condensed, thereby reducing the background noise. On the other hand, the OLED screen is formed by mixing monochromatic light, so that the emission of the monochromatic light by the screen is very easy to realize.

The display screen 5 is a display screen with a certain light transmission capacity, such as an OLED screen. The display screen 5 is provided with a fingerprint acquisition area, a plurality of light-emitting pixels are correspondingly arranged below the fingerprint acquisition area, a plurality of light-transmitting parts are arranged on the circuit layer 4 corresponding to each light-emitting pixel, in one implementation mode, a zone plate structure 3 capable of converging coherent enhanced light on the image sensor is arranged below the light-transmitting part corresponding to each light-emitting pixel, in the other implementation mode, a zone plate structure 3 capable of converging coherent enhanced light on the image sensor is arranged below the light-transmitting parts corresponding to the light-emitting pixels, so that when the electronic equipment is used for acquiring fingerprints, after a finger contacts the fingerprint acquisition area of the display screen 5, light incident on the image sensor is the light of the coherent enhanced part, the brightness of the greatly amplified light is higher, and the acquired fingerprint image has higher brightness, and is more clear.

In the prior art, the principle of pinhole imaging is utilized for fingerprint collection of the display screen 5, according to the characteristics of fingerprints, namely, the fingerprint comprises a ridge part and a valley part, when a finger is in contact with the display screen 5, the ridge part is in direct contact with the display screen 5, a gap is reserved between the valley part and the display screen 5, and light and dark stripes are formed on an image sensor according to different refractive indexes/reflectivities of light in different media, but only one pinhole can transmit light, so that the whole of a bright stripe and a dark stripe formed on the image sensor is darker, compared with the prior art, most of light-transmitting parts are utilized in the application, the light inlet quantity is ensured, meanwhile, the design of the zone plate structure 3 ensures that the total incident light is the addition related light, the brightness of the greatly amplified light is higher, and the brightness of the collected fingerprint image is higher, and is more clear. Meanwhile, since the light transmission area is increased, the relative height of the secondary peak of interference/diffraction generated by the fluctuation of light and the distance from the primary peak are also decreased. Thereby further improving optical resolution.

In conventional optics, a fresnel zone plate is considered to be a lens, with a focal length and depth of field. For a fixed object, the image surface can be imaged within a certain distance range; for a fixed image plane, an object can fall on the image plane within a certain range. In an off-screen fingerprint detection scenario, the object distance is fixed, and thus the image distance is also fixed, and the imaged image should fall on the sensor. However, due to the precision limitation of the assembly, the image sensor is often not accurately located on the image plane, but has a certain error. At this time, a relatively large depth of field is required to accommodate the error. If the zone plate structure is set to have only one ring or a small number of rings, then there may be a large depth of field to allow for this error. In general, in the present application, the depth of field can be considered as focal length/wavelength band number.

The imaging layer 1 is arranged above the image sensor, the imaging layer 1 is arranged above or below the circuit layer 4, the circuit layer 4 comprises a plurality of layers of circuits for driving light-emitting pixels, the circuits in the plurality of layers of circuit layers 4 are stacked in an interlaced mode, the interlaced circuit layer 4 is provided with a plurality of light-transmitting parts, the light-transmitting parts can be regular shapes or irregular shapes, and in practical application, the plurality of light-transmitting parts can be the situation shown in fig. 7A and 7B and comprise a plurality of relatively large light-transmitting parts, for convenience of description, the relatively large light-transmitting parts are called as first light-transmitting parts, and the first light-transmitting parts are enough to arrange at least one zone plate structure 3 at the light-transmitting parts; it is also possible that the plurality of light transmission portions are the case as shown in fig. 5, all of which have relatively small areas, and for convenience of description, the relatively small light transmission portion is referred to as a second light transmission portion, which means that a plurality of wavelength bands are not sufficiently provided at the light transmission portion. For the cases shown in fig. 7A and 7B, several light transmission portions (first light transmission portions) having relatively large areas are selected, and the corresponding zone plate structures 3 are disposed at the positions of the imaging layers 1 corresponding to the selected first light transmission portions. Referring to fig. 8A and 8B, a plurality of zone plate structures 3 are disposed on the imaging layer 1, and each zone plate structure 3 is respectively matched with a corresponding first light transmission portion. Note that the zone plate structure in this case is only partially exposed, and the zone plate structure 3 provided in the first light transmission portion refers to a structure including a light-shielding band and a light-transmitting band which are arranged at intervals, and the zone plate structure 3 corresponds to a part of a complete concentric ring structure with respect to the complete concentric ring structure (see fig. 8A and 8B). The zone plate structures 3 corresponding to the first light transmission portions of different shapes are different. Each zone plate structure 3 is calculated and designed according to the principle of light interference, so that monochromatic light passing through the first light transmission part and the light transmission band is subjected to coherent enhancement and converged on the image sensor, and the light intensity is greatly amplified. The zone plate structure 3 corresponding to the above situation can be understood as that imaging holes with the same shape and size are arranged at the position of the corresponding imaging layer 1 below the selected first light transmission part, then the optical path from the light to a certain point on the image sensor 2 through the imaging holes is calculated according to the wavelength of the monochromatic light emitted into the imaging holes, coherent enhancement interference light and coherent cancellation interference light are obtained through calculation, wherein the light transmission setting is reserved at the coherent enhancement part, and the coherent cancellation part is shielded to form a shielding band, so that the light emitted into the image sensor is all in coherent addition effect, and the light intensity is greatly amplified. On the other hand, an excessively fine zone plate structure may be difficult to realize due to the relation of processing accuracy, so when the sum of the areas of the light-transmitting zones in the zone plate structure is larger than the sum of the areas of the light-shielding zones, the light-shielding zones may be removed, and the effect that the light passing through the imaging hole is enhanced as a whole can also be ensured. This reduces the light intensity somewhat, but is easier to process and also stronger than masking out the imaging aperture.

Further, the zone plate structure 3 is focal length, which is

Where k denotes the kth half-wave band, λ is the wavelength of the light wave, r_kIs the radius of the kth half-wave band. And thus to the imaging field angle and depth of field. That is, the object-image distance should be set such that light from an object point passes through the zone plate structure 3 and is focused on the image sensor. Through calculation, 3 light transmission parts are selected from the circuit layer 4, and corresponding zone plate structures 3 are arranged on the three light transmission parts, so that light rays passing through the 3 light transmission parts can find a light ray strengthening point on the image sensor. This is because 3 points can determine a circle so that the distance (optical path length) to the 3 points in the direction of the normal through the center of the circle is always the same and thus always coherent.

For the case shown in fig. 5, the areas of the second light transmission portions are relatively small, and each second light transmission portion is not enough to correspondingly set multiple wavelength bands (spaced light-shielding bands and light-transmitting bands), so that a complete wavelength plate structure 3 may be designed on the imaging layer 1, the complete wavelength plate structure 3 refers to a structure including a series of concentric rings, the concentric rings refer to a structure including spaced closed-loop light-shielding bands and closed-loop light-transmitting bands, as shown in fig. 9, the complete wavelength plate structure 3 is aligned with the second light transmission portions of the circuit layer 4, and the alignment criterion is to make the light-transmitting bands of the imaging layer coincide with the second light transmission portions of the circuit layer, preferably, the overlapping area of the second light transmission portions of the circuit layer 4 and the light-transmitting bands of the wavelength plate structure 3 meets the preset area threshold range, or has the largest overlapping area, so that the light transmittance is highest.

Further, the light emitting pixel layer includes light emitting pixels arranged in an array. A circuit layer 4 is provided below the light emitting pixel layer, the circuit layer 4 comprising a plurality of layers of circuits including circuits for driving and controlling the light emitting pixels. In addition, the circuit layer 4 may include circuits for other purposes. Based on the fact that the light-emitting pixels are coated with organic light-emitting materials and the like, the light-emitting pixels are not transparent, gaps are reserved among the light-emitting pixels, and light-transmitting parts exist on the circuit layer 4 corresponding to the gaps, so that the light-transmitting parts exist around the light-emitting pixels.

For example, a pixel period of 70 μm, where the opaque central portion is about 40 μm in diameter, a ring or rings of transparent regions may be provided in the 40 to 70 μm region outside the opaque portion.

On the other hand, the existing zone plate design is an integer ring, but in our solution it is not necessarily required to start with an integer ring. For example, a pixel period of 70 μm, for example, where the central portion of the opacity is about 40 μm in diameter, but depending on the wavelength of the light and the focal length, a zone plate is designed with a first ring of 30 μm in diameter and a second ring of 42 μm in diameter, not exactly 40 μm. However, according to the calculation of the formula, it can be found that the 1.9 th turn is exactly 40 μm, and at this time, the light-transmitting part between the 1.9 th turn and the 2.9 th turn can be reserved and the part between the 0 th turn and the 1.9 th turn can be shielded. This is also a complete band with coherence enhancement. In addition, the wave band designed in this way has a larger light transmission area than the light transmission area found in the circuit.

It is understood that the zone plate structure 3 mentioned in the present application is not an existing circular fresnel zone plate, but is designed according to the actual situation of the circuit layer 4, named zone plate structure 3 for ease of description.

It should be noted that one wavelength band plate structure 3 may correspond to one pixel, or one wavelength band plate structure 3 may correspond to a plurality of pixels. Finally, all the points converged on the image sensor are combined into a complete image. However, it is preferable that one of the zone plate structures 3 does not correspond to all of the light emitting pixels because if one of the zone plate structures 3 corresponds to all of the light emitting pixels, each zone may be too thin at the outer edge of the zone plate structure 3 to be processed.

It should be noted that the imaging aperture and the light-transmitting zone of the zone plate structure can be used as a light path, and can also be used as a through hole for routing circuit lines. For example, it can serve as a via for circuit connection of upper and lower layers or as a via for connection of a circuit layer with a pixel layer, so that it is more advantageous for design of a display screen.

The fingerprint acquisition device utilizes a plurality of light transmission parts to increase the light inlet quantity, and simultaneously utilizes the fact that the equivalent diameter of the plurality of light transmission parts, which is equivalent to the light transmission area, is increased compared with the prior art that only one light transmission part is selected for small-hole imaging, so that the diffraction phenomenon of light is weakened; on the other hand, the light intensity is improved through the zone plate structure 3, so that light rays are easily received by the image sensor, and the image definition and the resolution are improved.

In a second embodiment of the present application, an electronic device for imaging an object outside a display screen provides a function to act as a camera, in particular a front-facing camera.

Existing electronic equipment, such as smart mobile phone, panel computer all include leading camera and rear camera, leading camera including set up the mirror unthreaded hole on the display screen and be located the image sensor behind the mirror unthreaded hole, the optical image that the target object generated through the camera lens is projected on the image sensor surface, leading camera mainly is used when autodyne and video conversation. That is to say, the front camera needs to open a hole on the display screen, which is also the reason why the existing electronic device cannot realize a real full screen.

The application provides an image acquisition device of setting under display screen, uses on the electronic equipment that has the display screen, is used for gathering the image of the outer target object of display screen, can solve among the prior art because leading camera's setting, can't realize the problem of full screen.

It should be noted that all colors in nature that can be sensed by human eyes can be obtained by combining different intensities of three color wavelengths of red, green and blue, which is the principle of three primary colors.

The application provides an image acquisition device of setting under display screen, see fig. 10A and fig. 10B, including circuit layer 4, imaging layer 1 and three image sensor, wherein three image sensor be for being used for receiving ruddiness image sensor 201, receiving green glow image sensor 202 and receiving blue light image sensor 203 respectively, be equipped with three kinds of zone plate structures 3 on the imaging layer 1 that three image sensor corresponds, three kinds of zone plate structures 3 are designed for ruddiness, green glow and blue light according to light respectively and obtain. When an object outside the display screen 5 is imaged, light emitted by the object passes through the light-transmitting part of the circuit layer 4 and the light-transmitting belt of the imaging layer 1 and falls on the three image sensors respectively, and finally images on the three image sensors are processed into a finished color image.

The second embodiment of the present application is designed based on the principle of the first embodiment, and the design principle of the three zone plate structures 3 is not described in detail.

Further, in order to improve the imaging quality, referring to fig. 11 and 12, in an implementation manner, low-resolution display may be implemented in a partial area of the display screen, and specifically, the number of light-emitting pixels per unit area may be reduced; for example, one or more light-emitting pixel points which are not important are selected on the display screen, for example, one light-emitting pixel is reduced at a position where electric quantity is displayed, so that a relatively complete imaging hole can be exposed at a position corresponding to the light-emitting pixel, and a relatively complete zone plate structure 3 can be arranged at the position of the imaging hole. Furthermore, in order to reduce the influence on the display effect, several light-emitting pixels are removed at intervals, namely at least one light-emitting pixel is arranged between two adjacent missing light-emitting pixels, and the corresponding light-transmitting parts left after the light-emitting pixels are removed can be covered by one zone plate, so that the light intensity is greatly increased.

Further, the pixels of the same color are selected for removal, that is, all the missing pixels are pixels of the same color. For example, if only green and red are required to display the charge, then the blue emitting pixels can be removed at the display charge location.

The imaging device matched with the two realizable modes comprises an imaging layer 1 and an image sensor 2. Referring to fig. 3, the imaging layer 1 includes a plurality of imaging holes, and each of the imaging holes is provided with a zone plate structure 3, as shown in fig. 4, the zone plate structure 3 includes light-shielding zones and light-transmitting zones arranged at intervals, each zone plate structure 3 is calculated and designed according to the principle of light interference, so that monochromatic light passing through the light-transmitting zone is coherently enhanced and converged on the image sensor, and the light-shielding zones are portions where the monochromatic light is coherently and destructively converged on the image sensor by calculation, so that the light converged on the image sensor is coherent enhanced light, and the light intensity is greatly amplified. During imaging, each zone plate structure 3 generates an image spot, and a plurality of image spots are spliced together to obtain a complete target image. The splicing process comprises the steps of reverse image correction, brightness correction, splicing and the like.

Compared with the existing MAPI imaging, the pinhole imaging utilized by MAPI imaging is free diffraction imaging, and the light is converged to form the image through the zone plate structure 3 in the application. Thus, the imaging device of the present application has a higher resolution and higher energy at the image point with the same aperture. This is because the zone plate structure 3 eliminates the light waves in opposite phases from canceling each other, thus greatly enhancing the energy at the point of convergence. With 20 half-wavelength bands in the zone plate structure 3, the energy of the image point is about 400 times that of the free diffraction of the aperture. In addition, the small hole imaging cannot use a larger aperture, otherwise the image is blurred; when the imaging device of the application images, because the light converging effect of the thin lens is similar, a large aperture can be used, image blurring is not needed to be worried about, and the light transmittance can be further increased by the large aperture, so that the imaging energy is enhanced.

The two realization modes can lead the imaging hole to collect larger light energy for imaging. Meanwhile, when a far target object is imaged, each point on the surface of the target object can form a plurality of image points with parallax on the image sensor through the imaging hole, so that the depth information of the image points can be calculated based on the image points, or noise filtering or resolution enhancement is performed. For example, assuming that the imaging aperture has a period of 0.5mm, that is, one imaging aperture is disposed every 0.5mm, and an image sensor of 5mm × 5mm is used, 100 image spots can be obtained by one imaging. For distant objects above 30mm, it will have an image within these 100 image spots. Therefore, sufficient signal processing calculation can be carried out based on the 100 image spots, noise is eliminated, resolution is improved, or accurate depth information is calculated.

In the embodiment, no holes visible to naked eyes are formed in the display screen, so that the display cannot be seriously affected, and the full-screen display can be really realized. In addition, the thickness can be greatly reduced due to the absence of the lens, and the lens is easier to install below the display screen.

In order to further reduce the diffraction phenomenon of light, it is preferable to shorten the distance between the circuit layer 4 and the imaging layer 1 as much as possible, and as in the first and second embodiments, the imaging layer 1 is closely attached to the circuit layer 4.

To achieve this, photolithography, which is a process technique of transferring a circuit pattern onto a single crystal surface or a dielectric layer using the principle of optical-chemical reaction and chemical and physical etching methods to form an effective pattern window or a functional pattern, may be used. Specifically, a pattern on a reticle is transferred to a substrate by means of a photoresist (also known as a photoresist) under the action of light. The main process is as follows: firstly, irradiating ultraviolet light on the surface of a substrate attached with a layer of photoresist film through a mask plate to cause the photoresist in an exposure area to generate chemical reaction; dissolving and removing the photoresist (the former is called positive photoresist and the latter is called negative photoresist) of the exposed area or the unexposed area by a developing technology, so that the pattern on the mask is copied to the photoresist film; finally, the pattern is transferred to the substrate by using an etching technology.

Obviously, the use of a mask is inevitably required by the photolithography technique, and the applicant has considered that if a manufacturer uses the photolithography technique to produce the circuit layer 4 simultaneously with the imaging layer 1, a new set of masks needs to be designed according to the imaging apparatus of the present application, but the masks are very expensive, and in order to solve this problem, the present application proposes to fix the imaging layer 1 on the image sensor.

The electronic device for imaging an object touching the display screen shown in fig. 13 is largely the same as the first embodiment, except that: a transparent glass layer 7 is arranged on the image sensor 2, an imaging layer 1 is arranged on the upper surface of the transparent glass layer 7, and the zone plate structure 3 on the imaging layer 1 corresponds to the light-transmitting part of the upper circuit layer 4.

Similarly, the electronic apparatus for imaging an object outside the display screen shown in fig. 14A and 14B is mostly the same as the second embodiment, except that: a transparent glass layer 7 is arranged on each image sensor, an imaging layer 1 is arranged on the upper surface of the transparent glass layer 7, and the zone plate structure 3 on the imaging layer 1 corresponds to the light-transmitting part of the upper circuit layer 4.

Imaging layer 1 is fixed on image sensor through transparent glass, adjusts the distance between circuit net and the imaging layer 1 through the thickness of adjusting transparent glass, and when production, the imaging device that will produce directly the laminating under the display screen can. The transparent glass does not influence the convergence of light on the image sensor, and simultaneously, the production cost is greatly reduced.

In addition, for the outer edge of the zone plate structure, each zone may be too thin to be machined. By providing the imaging layer 1 on the upper surface of the image sensor 2 on which the transparent glass layer 7 is provided, processing is easier.

The imaging layer 1 in the above embodiments of the present application is an imaging plate structure, and is disposed above or below the circuit layer 4. The present application proposes another realizable way of the imaging layer 1, by using the circuit layer 4 itself, when designing a circuit, the intricate circuit lines of the circuit layer 4 are designed to a configuration including a light-transmitting portion and a light-shielding portion, for example, in a portion where light transmission is required, the circuit is set to be sparse or even transparent, and in a portion where light transmission is not required, the circuit is set to be dense and light-tight. Wherein, the light-transmitting part and the light-shielding part play the role of a zone plate structure, namely, the circuit layer can be regarded as the zone plate structure. The light transmission part is a light coherence enhancement part, and the light shielding part is a light coherence cancellation part, so that the light passes through the light transmission part of the circuit layer 4 and then is converged on the image sensor.

In addition, the imaging layer can be made of conductive materials, the imaging layer is equivalent to a large-area conductor and can be used for supplying power, and compared with the power supplied through a wire, the imaging layer is smaller in resistance and more stable in voltage. When the imaging layer sets up in the display screen, each part that needs the power supply in the display screen, for example light emitting pixel, distance sensor, ambient light sensor etc. all can get the electricity from the imaging layer.

Further, when power is needed to be supplied, the shading strips can be communicated through connecting pieces to ensure the whole constant voltage, and the connecting pieces are made of conductive materials. For example, the shading tapes may be connected by a number of connecting strips.

Various different modes can be selected for the zone plate structure 3, such as a zone plate with even-number zone shielding, a zone plate with odd-number zone shielding, a circular ring zone plate, a rectangular grid zone plate, and the like, or other zone plates specially designed to meet the requirements of different imaging conditions.

Further, the present application discloses a tilted zone plate structure for use in oblique angle ray imaging, see fig. 15 and 16, which provide tilted zone plate structures suitable for two different oblique angle ray imaging, respectively. The light-blocking band and the light-transmitting band of the tilted zone plate structure 301 are not concentric circles, but are tilted on one side.

Referring to fig. 17, fig. 17 shows how to obtain the tilted zone plate structure 301, first, a concentric ring zone plate structure, i.e. a positive zone plate structure 302, is placed on the normal plane of the incident light (i.e. the wavefront of the incident plane wave), orthogonal to the incident optical axis; then, the intersection point of the focal plane of the positive band plate structure 302 and the optical axis of the incident light is taken and recorded as point F, which is the focus of the positive band plate structure 302; finally, the center of the positive zone plate structure 302 is projected with the point F as the center, and the projection falling on the diffraction plane is the tilted zone plate structure 301. The tilted zone plate structure 301 has the best focusing effect on obliquely incident light.

In a specific example, see fig. 18, comprising an image sensor 2, a tilted zone plate structure 301 and a transparent glass plate 8. As shown in fig. 19, the optimum imaging angle θ of the tilted zone plate structure 301 in this example is 50 °, the refractive index of the transparent glass plate 8 is 1.5, and the total reflection occurs at the glass-air interface when the light in the transparent glass plate 8 propagates toward the finger printing surface in the direction of 50 °; at the glass-skin interface, the total reflection will be destroyed and most of the light will be transmitted out of the transparent glass plate 8. Thus, the reflected light passes through the tilted zone plate structure 301, and after convergent imaging, the valley-ridge lines will have strong contrast on the output image. On the other hand, after external ambient light enters the glass from air, the angle of the external ambient light is smaller than 41.8 degrees, and the external ambient light cannot be well converged and imaged through the inclined zone plate structure 301, so that the ambient light noise is reduced.

Further, the inclined angle of the tilted zone plate structure 301 should be away from the incident direction of the ambient light. For example, when an imaging device using an inclined zone plate structure is used in a mobile device such as a mobile phone, the inclination angle thereof should be toward the lower end of the display screen, which is a direction away from the sunlight in general.

It should be noted that the inclination angle of the tilted zone plate structure described in the present application refers to an incident angle at which the tilted zone plate structure can achieve an optimal converging effect of the incident light, that is, the inclination angle corresponds to the incident angle of the incident light.

The tilted zone plate structure 301 in this embodiment may be used in all other embodiments in this application. Especially the use of the tilted zone plate structure 301 in fingerprint acquisition is optimal because the tilted angle of the tilted zone plate structure can accept the total reflected light with an intensity of about 6 times the normal incidence.

The application also provides a split-field imaging device, which comprises at least two imaging devices, wherein each imaging device comprises a zone plate structure, and an image sensor is arranged below the zone plate structure, wherein each zone plate structure can correspond to one image sensor, and a plurality of zone plate structures can also correspond to one image sensor; the corresponding tilted field of view rays cooperate with the tilted zone plate structures 301, each zone plate structure being configured to focus the object field of view rays onto a corresponding image sensor, respectively. The target object is divided into a plurality of sub-fields of view to be imaged on corresponding imaging devices respectively, and finally the partial images of the target object obtained on the imaging devices are spliced into a complete target object image through image processing.

To the above-mentioned image device of dividing the visual field, this application still provides an equipment, including display screen and above-mentioned image device of dividing the visual field, divide the visual field image device to correspond the printing opacity portion that sets up below the display screen.

The minimum unit for receiving the optical signal in the image collector is a photosensitive pixel (also called photosensitive pixel, pixel), and a plurality of photosensitive pixels are usually arranged in the image collector. Photosensitive pixels used by image collectors in the market all have wider field angles. The field angle of the photosensitive pixel refers to the maximum angle formed by incident light rays in different directions, which can be responded by the photosensitive pixel. When the existing image collector is used for directly imaging, the field angle is large, and the obtained image is not clear. The application further provides a narrow-field-of-view photosensitive pixel element.

As shown in fig. 20, a narrow-field photosensitive pixel element includes a photoelectric conversion unit and photosensitive pixels 9, a field diaphragm 10 is disposed on the photosensitive pixels 9, the field diaphragm 10 is a diaphragm with an opening in the middle, the opening can transmit light, and the part outside the opening cannot transmit light, or a light shielding wall 11 is disposed between two photosensitive pixels 9, or both the field diaphragm 10 and the light shielding wall 11 are disposed. The zone plate structure 3 is arranged above the photosensitive pixel 9, so that light rays emitted by an object point A in a set view field are converged in a small hole of a view field diaphragm 10 of the photosensitive pixel 9 through the zone plate structure 3, and correspondingly, the photoelectric conversion unit can receive the light rays with higher intensity, so that images in the view field of an object space can be imaged clearly, and effective output is generated; at an object point B outside the set field of view, the light emitted by the object point B will pass through the zone plate structure 3 and converge outside the aperture of the field stop 10 of the photosensitive pixel, so that the photoelectric conversion unit cannot sense or can only sense the light emitted by the object point outside the object field of view with low intensity, and then the image outside the object field of view cannot be acquired or the acquired part will not affect the imaging of the light in the object field of view on the photoelectric conversion unit, and cannot generate effective output. So that the angle of view of the photosensitive pixel can be defined, and in addition, the arrangement of the light blocking wall 11 can prevent crosstalk of large-angle light.

In the embodiments described above, a one-layer zone plate structure is used, and a zone plate structure generally does not have a converging effect on light rays in only one direction, but rather on light rays within a range, which is sometimes detrimental. The present application provides another embodiment based on the above embodiment, which is mostly the same as the above embodiment, except that a dual-layer zone plate structure is adopted, that is, a first zone plate and a second zone plate with the same structure, that is, an additional layer of identical zone plate structure is added on the basis of the single-layer zone plate structure in the above embodiment, the additional layer of zone plate structure may be disposed above or below the original zone plate structure, the light transmission bands of the two-layer zone plate structure may be completely aligned or have a certain offset, and two zone plate structures stacked up and down are disposed, as shown in fig. 21 and 22. Light rays in the direction of the connecting line between the central points of the two zone plate structures can penetrate through the two zone plates and form images, and light rays in other directions cannot. In some cases, the object to be measured is only extremely intense in a certain direction, such as the case of total internal reflection in a light guide plate. By arranging the double-layer zone plate structure, only light in a certain direction is received, for example, only reflected light generated by total reflection is received, so that the light intensity can be greatly increased, and the contrast is improved. On the other hand, when the field of view is small, the two-layer zone plate structure may function as a collimator.

In the description of the present application, it is to be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, are merely for convenience of description, and do not indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and thus, are not to be construed as limiting the present application. Further, in the description of the present application, "a plurality" means two or more.

The same and similar parts in the various embodiments in this specification may be referred to each other. The above-described embodiments of the present invention should not be construed as limiting the scope of the present invention.

Claims

1. An electronic device comprising an imaging device and a display screen, the imaging device comprising an imaging layer and an image sensor located on a lower side of the imaging layer, the display screen comprising a circuit layer;

when the circuit layer includes a plurality of first printing opacity parts be equipped with on the imaging layer with first printing opacity part one-to-one's imaging hole, every be equipped with the zone plate structure in the imaging hole, wherein, the area of first printing opacity part is enough to set up at least one zone plate structure, the zone plate structure includes shading band and printing opacity area, the zone plate structure makes the light of reflecting through the target assemble in image sensor is last to form images, wherein, the light that passes through the zone plate structure is totally coherent enhancement light.

2. The electronic device of claim 1, wherein the light-blocking bands are removed when a sum of areas of the light-transmitting bands of the zone plate structure within the imaging aperture is greater than a sum of areas of light-blocking bands.

3. The electronic device of claim 1, comprising at least three image sensors for receiving red, green, and blue light, respectively;

the imaging layer is provided with a zone plate structure corresponding to each image sensor;

4. The electronic device of claim 1, wherein the zone plate structure comprises first and second zone plates of identical structure, the first and second zone plates being arranged one above the other such that light in a line between center points of the first and second zone plates can pass through the first and second zone plates and be imaged.

5. The electronic device of claim 1, wherein the imaging layer is made of a conductive material.

6. The electronic device of claim 5, wherein the light shielding strips are connected to each other by a connecting member, and the connecting member is made of a conductive material.

7. The electronic device of claim 5, wherein the imaging layer is further configured to supply power.

8. An electronic device comprising a display screen, an imaging layer, and an image sensor;

the imaging layer is positioned below or above the circuit layer;

wherein the zone plate structure comprises a shading band and a transmitting band; when the target object contacts the display screen, after the target object reflects, the incident light passes through the light-transmitting part and the light-transmitting belt and is converged on the image sensor to form an image.

9. The electronic device of claim 8, wherein when at least two imaging holes are formed in the imaging layer, image-side fields of view of adjacent imaging holes do not coincide.

10. The electronic device of claim 8, wherein when at least two imaging apertures are formed in the imaging layer, object fields of view of adjacent imaging apertures coincide.

11. The electronic device of claim 8, wherein the number of imaging apertures is 3.

12. The electronic device of claim 8, further comprising light emitting pixels arranged in an array on the circuit layer, wherein the number of light emitting pixels per unit area is reduced, a plurality of imaging holes are formed in the imaging layer corresponding to the missing light emitting pixels, and a zone plate structure is disposed in each imaging hole.

13. The electronic device of claim 12, wherein at least one light-emitting pixel is spaced between two adjacent missing light-emitting pixels.

14. The electronic device of claim 8, wherein the distance between the image sensor and the imaging layer is set such that light from a point on the object plane converges at a point on the image sensor.

15. The electronic device of claim 8, wherein the imaging aperture and the light-transmissive ribbon of the zone plate structure are also used for vias for circuit line routing.

16. The electronic device of claim 8, wherein the imaging layer is aligned with the circuit layer such that an area of overlap of the light-transmissive strip of the imaging layer with the second light-transmissive portion of the circuit layer is maximized or meets a predetermined area threshold range.

17. The electronic device of claim 8, comprising at least three image sensors for receiving red, green, and blue light, respectively;

18. The electronic device of claim 8, wherein the zone plate structure comprises first and second zone plates of identical structure, the first and second zone plates being arranged one above the other such that light in a line between center points of the first and second zone plates can pass through the first and second zone plates and be imaged.

19. The electronic device of claim 8, wherein the imaging layer is made of a conductive material.

20. The electronic device of claim 19, wherein the light shielding strips are connected to each other by a connecting member, and the connecting member is made of a conductive material.

21. The electronic device of claim 19, wherein the imaging layer is further configured to provide power.

22. An imaging device comprising an imaging layer, the imaging layer being located below or above a circuit layer;

the circuit layer comprises a plurality of second light-transmitting parts, the imaging layer comprises a plurality of imaging holes, zone plate structures are arranged in the imaging holes, the imaging layer is aligned with the circuit layer, so that light-transmitting belts of the imaging layer are overlapped with the second light-transmitting parts of the circuit layer, and one zone plate structure corresponds to a plurality of second light-transmitting parts;

wherein the zone plate structure comprises a shading band and a transmitting band; when the target object contacts the display screen, after the target object reflects, the incident light rays pass through the second light transmission part and the light transmission belt and are converged on the image sensor to form an image.

23. The imaging apparatus of claim 22, comprising at least three image sensors for receiving red, green and blue light, respectively;

24. An imaging device according to claim 22, wherein the zone plate structure comprises first and second zone plates of identical structure, the first and second zone plates being arranged one above the other so that light in a line between the central points of the first and second zone plates can pass through the first and second zone plates and be imaged.

25. The imaging apparatus of claim 22, wherein the imaging layer is made of a conductive material.

26. The imaging device as claimed in claim 25, wherein the light shielding strips are connected to each other by a connecting member, and the connecting member is made of a conductive material.

27. The imaging apparatus of claim 25, wherein the imaging layer is further configured to supply power.

28. An imaging layer comprising a zone plate structure formed by a circuit line arrangement, the zone plate structure comprising a light blocking portion and a light transmitting portion, wherein light passing through the zone plate structure is generally coherence enhancing light, the light transmitting portion focusing light reflected by a target onto an image sensor for imaging.

29. A tilted zone plate structure, wherein the tilted zone plate structure is obtained by:

30. A tilted zone plate structure according to claim 29, wherein the tilted zone plate structure has an inclined angle away from the incident direction of ambient light, said inclined angle being the angle of incidence θ of the incident light rays.

31. A split-field imaging device is characterized by comprising at least two imaging devices, wherein each imaging device comprises a zone plate structure, an image sensor is arranged below the zone plate structure, each zone plate structure corresponds to one image sensor, or a plurality of zone plate structures correspond to one image sensor; each of the zone plate structures is for converging object field rays onto a corresponding image sensor, respectively, wherein corresponding tilted field rays cooperate to use the tilted zone plate structure of claim 29.

32. An imaging layer comprising the tilted zone plate structure of claim 29 or 30.

33. The narrow-field-of-view photosensitive pixel is applied to the electronic device of claim 1 or 8, wherein a field-of-view diaphragm is arranged on the upper surface of the photosensitive pixel, a zone plate structure is arranged above the field-of-view diaphragm, the zone plate structure comprises a shading zone and a light-transmitting zone, and the zone plate structure enables light reflected by a target to be converged on an image sensor for imaging;

34. The narrow-field photosensitive pixel of claim 33, wherein a light-shielding wall is disposed between adjacent photosensitive pixels, the light-shielding wall being located on an upper side of the photosensitive pixel.