CN114167664A

CN114167664A - Optical lens and terminal device

Info

Publication number: CN114167664A
Application number: CN202010848962.8A
Authority: CN
Inventors: 费永浩; 代郁峰; 傅正华; 邹正鹏
Original assignee: XFusion Digital Technologies Co Ltd
Current assignee: XFusion Digital Technologies Co Ltd
Priority date: 2020-08-21
Filing date: 2020-08-21
Publication date: 2022-03-11

Abstract

The present application provides an optical lens and a terminal device, and the optical lens can be applied in a terminal device with a camera. The optical lens comprises: an infrared cut-off filter; a color filter; a diffractive optical element, which is arranged between the color filter and the infrared cut-off filter, and is used to diffract the output light of the infrared cut-off filter, and to diffract the output light of the infrared cut-off filter. The diffracted light is transmitted to the color filter, so that the light of the first color that is not transmitted (reflected or unusable) of the first pixel of the color filter is diffracted to the second pixel, and the light of the first color is diffracted to the second pixel. Light is transmitted on the second pixel, which is adjacent to the first pixel. The optical lens provided by the present application, by adding a layer of diffractive optical elements between the color filter and the infrared cut-off filter, through the diffraction of light by the diffractive optical element, a certain pixel of the color filter is not transmitted. The light diffracted to the adjacent pixels of the color filter is transmitted, thereby improving the optical utilization rate.

Description

Optical lens and terminal device

Technical Field

The present invention relates to the field of photography or video recording, and more particularly, to an optical lens and a terminal device.

Background

In a conventional camera used in the security or terminal field, a Charge Coupled Device (CCD) or a Complementary Metal Oxide Semiconductor (CMOS) type camera is generally used. The CCD/CMOS lens mainly comprises: the CCD/CMOS photosensitive element comprises a detector, a Color Filter and a micro lens. The light sensing element is used for converting detected light into current, the color filter is used for distinguishing different colors, and the micro lens is used for further collecting light entering the light sensing element. In order to obtain color images, there are generally two types of color filters: RGB (red green blue) type color filters and CMY (cyan/magenta/yellow) type color filters. The RGB type color filter limits the light of each Pixel (Pixel) to a single color resulting in approximately 66% loss of light energy, whereas the CMY type color filter uses mixed colors, where the energy of 2 colors of light is available per Pixel, but the light loss is still around 33%. Therefore, the optical utilization rate of the existing optical camera is low, and how to improve the optical utilization rate of the optical camera is called as a problem which needs to be solved urgently at present.

Disclosure of Invention

The application provides an optical lens and terminal equipment, can promote optical lens's optics utilization ratio.

In a first aspect, an optical lens is provided, the optical lens comprising: an infrared cut filter for reducing crosstalk between pixels of different colors on the color filter; a color filter for filtering the received light; and the diffractive optical element is arranged between the color filter and the infrared cut-off filter and is used for diffracting the output light of the infrared cut-off filter and transmitting the diffracted light to the color filter, so that the light of a first color which is not transmitted on a first pixel of the color filter is diffracted to a second pixel, the light of the first color is transmitted on the second pixel, and the second pixel is adjacent to the first pixel.

According to the optical lens provided by the first aspect, the layer of diffractive optical element is added between the color filter and the infrared cut-off filter, and light which is not transmitted by a certain pixel of the color filter is diffracted to the adjacent pixel of the color filter for transmission through diffraction of the diffractive optical element to the light, so that the optical utilization rate is improved.

It should be understood that, in the embodiment of the present application, the light of the first color that is not transmitted on the first pixel may be understood as that the light of the first color is reflected or absorbed on the first pixel, cannot be transmitted, and thus cannot be utilized on the first pixel.

With reference to the first aspect, in certain implementations of the first aspect, the diffractive optical element includes a periodic micro-nano structure.

With reference to the first aspect, in certain implementation manners of the first aspect, the periodic micro-nano structure includes an inclined periodic micro-nano structure or a vertical periodic micro-nano structure.

The inclined micro-nano structure can be understood as that the micro-nano structure is not parallel to the normal direction of the surface of the DOE layer, namely the micro-nano structure is inclined relative to the surface of the DOE layer, and the included angle between the micro-nano structure and the surface of the DOE layer is not a right angle. The perpendicular micro-nano structure can be understood as that the micro-nano structure is perpendicular to the surface of the DOE layer, namely the micro-nano structure is parallel to the normal direction of the surface of the DOE layer, and the included angle between the micro-nano structure and the surface of the DOE layer is a right angle.

With reference to the first aspect, in certain implementation manners of the first aspect, the tilted periodic micro-nano structure or the vertical periodic micro-nano structure is a grating.

With reference to the first aspect, in certain implementations of the first aspect, the tilted periodic micro-nano structure diffracts light of only a positive first order or a negative first order. In the case where the diffractive optical element includes a tilted periodic micro-nano structure, consecutive 3 pixels on the diffractive optical element repeat for one period, each of the 3 pixels diffracts light of a single color, and each of the 3 pixels diffracts light of a single color in a different color.

For example, 3 consecutive pixels on the DOE diffract blue light, green light, and red light in sequence, or 3 consecutive pixels on the DOE diffract green light, red light, and blue light in sequence.

With reference to the first aspect, in certain implementations of the first aspect, light diffracted by a vertical periodic micro-nano structure (for example, a grating) is bilaterally symmetric, in a case that the diffractive optical element includes the vertical periodic micro-nano structure, two consecutive pixels on the diffractive optical element repeat in one period, after M repetition periods, there are pixels transmitting green light on both sides of 2 × M pixels, respectively, each of two adjacent pixels on the diffractive optical element diffracts light of two different colors, and M is a positive integer.

With reference to the first aspect, in certain implementations of the first aspect, the diffractive optical element includes a plurality of different regions, the plurality of different regions differing in a structural parameter, the structural parameter including: at least one of a period, a duty cycle, or an etch depth. In this implementation, the angle of the CRA incident on the sensor varies due to different fields of view. That is to say, the angles of incidence on the DOE by the same light are different, and in order to match the actual transmission field of view of the light beam, the function of the DOE is further improved, the DOE layer can be partitioned, and the working efficiency of the DOE can be further improved as different regions correspond to different incidence angles of the light.

With reference to the first aspect, in certain implementations of the first aspect, the plurality of different regions have the same geometric center. In the implementation mode, because the light is centrosymmetric when being incident on the sensor, when the DOE layer is partitioned, the DOE layer can be partitioned in a centrosymmetric mode, namely a plurality of different regions have the same geometric center, so that the actual transmission mode of the light can be matched, the complexity of partition design is reduced, and the implementation is facilitated.

With reference to the first aspect, in certain implementations of the first aspect, the diffractive optical element includes a two-dimensional periodic micro-nano structure, a third pixel on the diffractive optical element corresponds to a fourth pixel on the color filter, and light diffracted by the third pixel is transmitted to upper, lower, left, and right (or front, rear, left, and right) pixels adjacent to the fourth pixel. That is, the diffraction of the light beam in four directions of up, down, left and right (or front, back, left and right) is realized by adopting a two-dimensional periodic micro-nano structure.

With reference to the first aspect, in certain implementations of the first aspect, the optical lens further includes a microlens disposed between the color filter and the ir-cut filter, and the diffractive optical element is disposed between the microlens and the ir-cut filter.

With reference to the first aspect, in certain implementations of the first aspect, the optical lens further includes a microlens disposed between the color filter and the infrared cut filter, and the diffractive optical element is disposed between the microlens and the color filter.

With reference to the first aspect, in certain implementations of the first aspect, an adhesive layer is disposed between the diffractive optical element and the color filter.

With reference to the first aspect, in certain implementations of the first aspect, the light of the first color is any one of red light, blue light, or green light; alternatively, the light of the first color is blue and green light, or red and green light.

With reference to the first aspect, in certain implementations of the first aspect, the color filter is a red/green/blue filter, or a cyan/magenta/yellow filter.

The optical lens provided by the application can be applied to a camera, a video camera or terminal equipment with a camera, and the optical utilization rate of the optical lens can be improved.

In a second aspect, a terminal device is provided, which includes: a display screen for displaying a picture or video taken by the optical lens and the optical lens provided in any one of the above-mentioned first aspect or any one of the possible implementations of the first aspect.

The terminal equipment provided by the application can improve the optical utilization rate of the terminal equipment and improve the quality of shot pictures or videos due to the adoption of the optical lens provided by the embodiment of the application, so that the user experience is improved.

For example, the terminal device provided by the present application may be a mobile phone with a photographing function, or may also be a camera or a video camera.

Drawings

Fig. 1 is a schematic configuration diagram of a conventional CCD/CMOS lens.

Fig. 2 is a schematic view showing the RGB type color filter and the CMY type color filter when filtering.

Fig. 3 is a schematic structural diagram of an optical lens provided in the present application.

Fig. 4 is a schematic structural diagram of an optical lens provided in the present application.

Fig. 5 is a schematic structural diagram of an optical lens provided in the present application.

Fig. 6 is a schematic structural diagram of an example DOE layer provided in the present application.

Fig. 7 is a schematic diagram illustrating an example of a DOE layer diffracting light according to the present application.

Fig. 8 is a schematic diagram of diffracted light when an example of DOE layer provided by the present application is a grating structure of a vertical periodic micro-nano structure.

Fig. 9 is a schematic diagram of an arrangement manner of a DOE layer and a color filter when the DOE layer is a grating of a vertical periodic micro-nano structure according to an embodiment of the present disclosure.

FIG. 10 is a schematic diagram of another example of the arrangement of a DOE layer and a color filter when the DOE layer is a vertical periodic micro-nano grating provided in the present application,

fig. 11 is a schematic diagram of an arrangement of a DOE layer and a color filter when the DOE layer is a grating with a tilted periodic micro-nano structure according to an embodiment of the present disclosure.

FIG. 12 is a schematic diagram of different regions of an example DOE layer provided by embodiments of the present application.

Fig. 13 is a schematic diagram of an arrangement of a DOE and colors of corresponding pixels on a filter when a DOE layer is formed of a grating having a two-dimensional periodic micro-nano structure according to an example provided in the present application.

Detailed Description

The technical solution in the present application will be described below with reference to the accompanying drawings.

In the description of the embodiments of the present application, "/" means "or" unless otherwise specified, for example, a/B may mean a or B; "and/or" herein is merely an association describing an associated object, and means that there may be three relationships, e.g., a and/or B, which may mean: a exists alone, A and B exist simultaneously, and B exists alone. In addition, in the description of the embodiments of the present application, "a plurality" means two or more than two.

In the following, the terms "first", "second" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present embodiment, "a plurality" means two or more unless otherwise specified.

The structure of a conventional CCD/CMOS lens is shown in fig. 1, and mainly includes: a CCD/CMOS light sensing element 101, an infrared cut filter (IRCF) 103, and a lens 104. The CCD/CMOS photosensitive element 101 includes a detector 1011, a Color Filter 1012 and a MicroLens 1013. The IRCF103 is used to block infrared light from being received by the detector 1011 to reduce or reduce cross-talk between different colored pixels on the color filter 1012. The detector 1011 is used to convert the detected light into electrical current, the color filter 1012 is used to distinguish different colors, and the micro-lens 1013 further collects the light entering the light sensing element 101. In order to obtain color images, there are generally two types of color filters: RGB (red/green/blue) type color filters and CMY (cyan/magenta/yellow) type color filters.

Different combinations of the three primary colors of red, green and blue can be made to obtain different colors. For example, red (R) and blue (B) are mixed to obtain magenta (M) color, red (R) and green (green, G) are mixed to obtain yellow (Y), blue (B) and green (G) are mixed to obtain cyan (cyan, C), and red (R), blue (B), and green (G) are mixed to obtain white or black.

FIG. 2 is a schematic view showing RGB type color filters and CMY type color filters for filtering light. As shown in fig. 2, the RGB type color filter limits the light of each Pixel (Pixel) to a single color, i.e., each Pixel can only transmit one color of light, and absorbs (or reflects) the other two colors of light, and the absorbed (or reflected) light cannot be used, resulting in a loss of light energy of about 66%, whereas the CMY type color filter uses a mixed color, and can use the energy of 2 colors of light, i.e., each Pixel can transmit two colors of light, and absorb (or reflect) the other color of light, but the light loss is still about 33%.

The current full-color camera mainly includes RGB filters, CMY filters or RYB (red/yellow/blue) filters, wherein the CMY filters have the highest efficiency, but only 66%, and the optical utilization rate is low.

In view of this, the present application provides an optical lens, in which a layer of Diffractive Optical Elements (DOE) is added between a color filter and an infrared cut-off filter, and light that is not transmitted in a certain pixel of the color filter is diffracted to a pixel adjacent to the color filter for transmission through diffraction of the DOE to the light, so as to improve optical utilization.

It should be understood that in the embodiments of the present application, the color light that is not transmitted in a certain pixel may be understood as that the color light is reflected or absorbed, cannot be transmitted, and thus cannot be utilized in the pixel.

The optical lens provided by the application can be applied to a camera, a video camera or terminal equipment with a camera. The embodiments of the present application are not limited thereto.

Fig. 3 is a schematic structural diagram of an optical lens provided in the present application, and as shown in fig. 3, the optical lens 100 includes:

a CCD/CMOS photosensitive element 101, a DOE layer 102, an infrared cut filter 103, and a lens 104. The DOE layer 102 is located between the CCD/CMOS photosensitive element 101 and the infrared cut filter 103. In the embodiment of the present application, the CCD/CMOS photosensitive element may also be referred to as a sensor (sensor).

Fig. 4 is a schematic structural diagram of another example of an optical lens system provided in the present application, and as shown in fig. 4, the optical lens system 100 includes: a CCD/CMOS photosensitive element 101, a DOE layer 102, an infrared cut filter 103, and a lens 104. The CCD/CMOS photosensitive element 101 includes a detector 1011, a color filter 1012, and a microlens 1013. Since the DOE layer 102 is located between the color filter 1012 and the infrared cut filter 103. As shown in fig. 4, the DOE layer 102 may be added on the surface of the microlens 1013, that is, the DOE layer 102 is located between the microlens 1013 and the infrared cut-off filter 103, and this design structure may only add 1 DOE layer in a conventional camera, which is simple to implement, and in a specific implementation process, the distance between the DOE structure 102 and the color filter 1012 needs to be precisely controlled, and the diffraction angle of the DOE layer 102 needs to be matched with this distance, so as to ensure that the optimal effect is achieved.

Fig. 5 is a schematic structural diagram of another example of an optical lens system provided in the present application, and as shown in fig. 5, the optical lens system 100 includes: a CCD/CMOS photosensitive element 101, a DOE layer 102, an infrared cut filter 103, and a lens 104. The CCD/CMOS photosensitive element 101 includes a detector 1011, a color filter 1012, and a microlens 1013. Since the DOE layer 102 is located between the color filter 1012 and the infrared cutoff filter 103, as shown in fig. 5, the DOE layer 102 may be provided between the color filter 1012 and the microlens 1013, so that the distance between the DOE layer 102 and the color filter 1012 can be precisely controlled. Optionally, as shown in fig. 5, an adhesive layer 1014 may be further disposed between the DOE layer 102 and the color filter 1012, and the adhesive layer 1014 is used to control the distance between the color filter 1012 and the DOE layer 102.

It should be understood that the illustration in fig. 4 and 5 is merely an example of the DOE layer positions provided in the embodiments of the present application, and should not impose any limitation on the positions of the DOE layers in the embodiments of the present application.

It should also be understood that in the embodiments of the present application, the DOE layer 102 may be a sheet structure. For example, a sheet of DOE structure or DOE layer may be provided between the infrared cut filter 103 and the color filter 1012. Alternatively, a DOE structure or a DOE layer is provided between the microlens 1013 and the infrared cut filter 103.

It should also be understood that in the embodiments of the present application, the color filters 1012 may be RGB filters, CMY filters, or RYB (red/yellow/blue) filters.

Optionally, in this embodiment of the present application, the DOE layer may include a periodic micro-nano structure. The periodic micro-nano structure comprises an inclined periodic micro-nano structure or a vertical periodic micro-nano structure. The inclined micro-nano structure can be understood as that the micro-nano structure is not parallel to the normal direction of the surface of the DOE layer, namely the micro-nano structure is inclined relative to the surface of the DOE layer, and the included angle between the micro-nano structure and the surface of the DOE layer is not a right angle. The perpendicular micro-nano structure can be understood as that the micro-nano structure is perpendicular to the surface of the DOE layer, namely the micro-nano structure is parallel to the normal direction of the surface of the DOE layer, and the included angle between the micro-nano structure and the surface of the DOE layer is a right angle. In other words, in the embodiments of the present application, the DOE layer may include an optical element of a tilted periodic micro-nano structure or an optical element of a perpendicular periodic micro-nano structure.

Optionally, in this embodiment of the application, the tilted periodic micro-nano structure or the vertical periodic micro-nano structure may be a grating. The grating of the inclined periodic micro-nano structure and the grating of the vertical periodic micro-nano structure have different structural parameters and configuration modes.

It should be understood that, in this embodiment of the present application, the tilted periodic micro-nano structure or the vertical periodic micro-nano structure may be, besides a grating, another optical component having a tilted periodic micro-nano structure or a vertical periodic micro-nano structure, and this embodiment of the present application is not limited herein.

Fig. 6 is a schematic structural view of an example DOE layer provided in the present application. As shown in a of fig. 6, the DOE layer 102 includes a vertical periodic micro-nano structure, which may also be referred to as a binary (binary) periodic micro-nano structure in this embodiment, and light diffracted by the vertical periodic micro-nano structure (e.g., a grating) is symmetric. As shown in b of fig. 6, the DOE layer 102 includes tilted (tilted) periodic micro-nano structures, which diffract light in only the first order or the second order, i.e. in only one direction. Optionally, in this embodiment of the present application, the tilted periodic micro-nano structure may be a trapezoidal tilted periodic micro-nano structure or a blazed grating, and this embodiment of the present application is not limited herein.

Fig. 7 is a schematic diagram illustrating diffraction of light by the DOE layer according to an example of the present application. In the example shown in fig. 7, the DOE layer 102 includes a tilted (sloped) periodic micro-nano structure, and parameters of the grating structure at different pixels (pixels) on the DOE layer 102 are different, for example: the period, duty cycle and etch depth of the grating are different. The color filter 1012 shown in fig. 7 is a CMY filter, and before the color filter 1012, when light enters a grating corresponding to a C (cyan) color pixel on the filter 1012, since the C (cyan) color pixel (for example, the first pixel) on the filter transmits green light and blue light, red light is not transmitted (or may be understood as absorbing or reflecting), that is, the C (cyan) color pixel on the filter cannot utilize red light. The grating corresponding to the C color pixel on the filter diffracts the red light and transmits the green light and the blue light. The distance between the detector 1011 and the DOE layer 102 and the diffraction angle of red light are controlled, so that the red light is diffracted to the adjacent Y (yellow) color pixel (for example, the second pixel) on the filter, and the Y (yellow) color pixel on the filter transmits green light and red light and absorbs blue light. Thus achieving efficient use of red light.

The Y color pixel on the filter (e.g., the first pixel) transmits green and red light and does not transmit (absorb or reflect) blue light, i.e., the Y color pixel on the filter cannot utilize blue light, and therefore the grating corresponding to the Y color pixel on the filter diffracts blue light and transmits red and green light, so that the blue light is diffracted to the adjacent M (magenta) color pixel (e.g., the second pixel). While the pixel of the M (magenta) color on the filter transmits red light and blue light and absorbs green light, thereby achieving efficient use of blue light.

The pixels of the M (magenta) color on the filter transmit red and blue light and do not transmit (absorb or reflect) green light, i.e. the pixels of the M (magenta) color on the filter cannot utilize green light. Therefore, the grating corresponding to the M (magenta) pixel on the filter diffracts green light, transmits red and blue light, and diffracts the green light to the adjacent C color pixel. The pixel of the C (cyan) color on the filter transmits green and blue light and absorbs red light, thereby achieving efficient use of green light.

The next C (cyan) pixel on the filter 1012 transmits green light and blue light, and does not transmit (absorb or reflect) red light, so that the grating corresponding to the C color pixel on the filter 1012 diffracts red light, transmits green light and blue light, and further diffracts red light onto the Y color pixel adjacent to the filter, thereby forming a cycle, and further improving the utilization rate of incident light energy.

The optical lens provided by the application realizes the DOE function by utilizing the inclined or vertical periodic micro-nano structure (such as a grating), and the DOE layer is added between the color filter and the infrared cut-off filter, so that the light which is not transmitted by a certain pixel of the color filter is diffracted to the pixel adjacent to the color filter for transmission through the diffraction of the optical element of the DOE layer, and the optical utilization rate of the optical lens is further improved.

In the embodiment of the present application, the DOE layer may include a grating of a tilted periodic micro-nano structure or a grating of a perpendicular periodic micro-nano structure. Different DOE layer structures correspond to different grating configuration modes, and when the DOE layer comprises a grating structure of a vertical periodic micro-nano structure, because diffracted light is symmetrical, the problem of light receiving wavelength of pixels (pixels) on two sides of the grating needs to be considered. Fig. 8 is a schematic diagram showing diffracted light when the DOE layer includes a grating structure of vertical periodic micro-nano structures, in fig. 8, 102 denotes the DOE layer, 1012 denotes a CMY filter, and a grating corresponding to a yellow (Y) pixel on the color filter 1012 diffracts green and blue light, and it can be seen from fig. 8 that the green and blue light diffracted by the vertical grating structure are bilaterally symmetric, and are respectively diffracted to a cyan (C) color pixel adjacent to the yellow (Y) pixel.

Fig. 9 is a schematic diagram illustrating an arrangement of a DOE layer and a color filter when the DOE layer includes a vertical periodic micro-nano structured grating, as shown in fig. 9, 1012 denotes a CMY filter, 102 denotes the DOE layer, 1021, 1022, and 1023 on the DOE layer 102 are different pixels on the DOE layer 102, the different pixels diffract light of different colors, and parameters of grating structures on the different pixels are different. 10121. 10122 and 10123 denote pixels of different colors on the CMY filter 1012, respectively. The pixel 10121 on the CMY filter corresponds to the pixel 1021 on the DOE layer, the pixel 10122 on the CMY filter corresponds to the pixel 1022 on the DOE layer, the pixel 10123 on the CMY filter corresponds to the pixel 1023 on the DOE layer, and the pixel 1023 on the DOE layer DOEs not have a grating structure.

As shown in fig. 9, the grating on the 1021 pixel diffracts blue and green light, transmits red light, and diffracts the blue and green light onto two pixels adjacent to the pixel 10121 on the filter, the two pixels adjacent to the pixel 10121 being the two pixels 10122, or the pixel 10122 and the pixel 10123. The red light is transmitted to the corresponding pixel 10121. The grating on pixel 1022 diffracts red and green light to transmit blue light and diffracts the red and green light onto two pixels 10121 on the filter adjacent to the pixel 10122, or diffracts the red and green light onto the

pixels

10121 and 10123 on the filter adjacent to the pixel 10122 to transmit blue light onto the corresponding pixel 10122. For the pixel 10121 on the filter, the transmitted light is red light, and the diffracted red light and green light from 1022 are mixed into yellow light, so the pixel 10121 on the filter is a yellow pixel. For the pixel 10122 on the filter, blue light is transmitted, and blue light and green light diffracted by 1021 are transmitted, and the blue light and the green light are mixed into cyan light, so the pixel 10122 on the filter is a cyan pixel. For the pixel 10123 on the filter, because the pixel 1023 on the DOE layer corresponding to the pixel 10123 DOEs not have a grating structure, the pixel 10123 receives 1022 red light and green light diffracted by the grating on the pixel 1021, or receives blue light and green light diffracted by the grating on the pixel 1021, and because full-color display is required, the pixel 10123 needs to display green, so that the pixel 1023 corresponding to the pixel 10123 needs to be set as a pixel which transmits green light, and the pixel which transmits green light and reflects or absorbs red light and blue light, so that green light can be displayed on the pixel 10123. That is, the pixels 1021 and the pixels 1022 on the DOE layer 102 are repeatedly present as one unit, and after the repetition twice, the pixels 1023 transmitting green light are disposed on both sides of the two pixels 1021, respectively. The color filters 1012 are configured to transmit yellow (red green), cyan (blue green), and green light. The yellow pixel and the cyan pixel are repeatedly arranged as a unit, and then the green pixels are respectively present on both sides, thereby realizing full-color display.

Fig. 10 is a schematic diagram illustrating another example of arrangement of DOE layers and color filters when the DOE layers provided by the present application include a vertical grating configuration, as shown in fig. 10, 1012 denotes a CMY filter, 102 denotes a DOE layer, 1021, 1022, and 1023 on the DOE layer 102 are different pixels on the DOE layer 102, respectively, where different pixels diffract light of different colors, and parameters of grating structures on different pixels are different. 10121. 10122 and 10123 denote pixels of different colors on the CMY filter 1012, respectively. The pixel 10121 on the CMY filter corresponds to the pixel 1021 on the DOE layer, the pixel 10122 on the CMY filter corresponds to the pixel 1022 on the DOE layer, the pixel 10123 on the CMY filter corresponds to the pixel 1023 on the DOE layer, and the pixel 1023 on the DOE layer DOEs not have a grating structure. The grating on pixel 1021 diffracts blue and green light, transmits red light, and diffracts the blue and green light to pixel 10122 and pixel 10123 on the filter adjacent to pixel 10121. The red light is transmitted to the corresponding pixel 10121. The grating on pixel 1022 diffracts red and green light, transmits blue light, diffracts red and green light onto

pixels

10121 and 10123 on the filter adjacent to pixel 10122, and no grating structure is present on pixel 1023 on the DOE layer. Unlike fig. 9, in the example shown in fig. 10, a pixel 1021 diffracting blue and green light and a pixel 1022 diffracting red and green light on the DOE layer are present only once as a unit, and then a pixel 1023 transmitting green light is added on both sides, respectively. In the example shown in fig. 10, the yellow pixel and the cyan pixel on the filter are repeated once as a unit, and then there are pixels transmitting green light on both sides, respectively. The filters 1012 are configured for yellow (red green), cyan (blue green) and green transmission. The yellow pixel and the cyan pixel are repeated once as a unit, and then green pixels are respectively present on both sides, thereby realizing full-color display.

It should be understood that, in the embodiment of the present application, when the DOE layer includes a grating of a vertical periodic micro-nano structure, the number of times that two pixels in succession appear as one unit on the DOE layer may be other values. The embodiments of the present application are not limited thereto.

That is, in the embodiment of the present application, in the case where the diffractive optical element includes the vertical periodic micro-nano structure, two pixels (for example, 1021 and 1022 in the example shown in fig. 9 and 10) that are continuous on the diffractive optical element repeat one period, after M (for example, M is 2 in the example shown in fig. 9 and M is 1 in the example shown in fig. 10) repeating periods, pixels that transmit green light are present on both sides of 2 × M pixels, respectively, and each of two pixels adjacent on the diffractive optical element diffracts light of two different colors, where M is a positive integer.

Fig. 11 is a schematic diagram illustrating an arrangement of a DOE layer and a color filter when the DOE layer includes a grating having a tilted periodic micro-nano structure according to an example provided by the present application. As shown in fig. 11, 1012 denotes a CMY filter, 102 denotes a DOE layer, 1021, 1022, and 1023 on the DOE layer 102 are different pixels on the DOE layer 102, respectively, the different pixels diffract light of different colors, parameters of grating structures on the different pixels are different, and the grating structure on each pixel diffracts light of a single color. 10121. 10122 and 10123 denote pixels of different colors on the CMY filter 1012, respectively. The pixel 10121 on the CMY filter corresponds to the pixel 1021 on the DOE layer, the pixel 10122 on the CMY filter corresponds to the pixel 1022 on the DOE layer, and the pixel 10123 on the CMY filter corresponds to the pixel 1023 on the DOE layer.

As shown in fig. 11, the grating on 1021 pixel diffracts blue light, transmits red and green light, diffracts blue light onto the pixel 10122 on the filter adjacent to the pixel 10121, and transmits red and green light onto the corresponding pixel 10121. The grating on pixel 1022 diffracts green light, transmits blue and red light, diffracts green light onto a pixel 10123 on the filter adjacent to the pixel 10122, and transmits blue and red light onto the corresponding pixel 10122. The grating on the 1023 pixel diffracts red light, transmits blue and green light, diffracts red light onto the next pixel 10121 on the filter adjacent to the pixel 10123, and transmits blue and green light onto the corresponding pixel 10123. And circulating in sequence. For the pixel 10121 on the filter, the transmitted light is red light and green light, and 1023 diffracted red light, red light and green light are mixed into yellow light, so that the pixel 10121 on the filter is a yellow pixel. For pixel 10122 on the filter, it transmits blue and red light, and 1021 diffracted blue light. The blue light and the red light are mixed into magenta (M) light, and thus the pixel 10122 on the filter is a magenta pixel. For pixel 10123 on the filter, it transmits blue and green light, and 1022 diffracted green light. The blue light and the green light are mixed into cyan (C) light, and thus, the pixel 10123 on the filter is a cyan pixel. That is, the pixel 1021, the pixel 1022, and the pixel 1023 on the DOE layer 102 repeatedly appear as one unit. The yellow pixel, the magenta pixel and the cyan pixel on the filter are correspondingly repeated as a unit, thereby realizing full-color display.

That is, in the embodiment of the present application, in the case that the DOE includes a tilted periodic micro-nano structure, consecutive 3 pixels ((for example, three

pixels

1021, 1022, and 1023 in the example shown in fig. 11) on the DOE repeat with one period, each of the 3 pixels diffracts light of a single color, and each of the 3 pixels diffracts light of a single color with a different color.

It should be understood that, in the embodiment of the present application, when the DOE includes the tilted periodic micro-nano structure, the number of times that consecutive 3 pixels on the DOE layer repeatedly appear as one unit is not limited. For example, 1 time, 2 times, 3 times, etc. The embodiments of the present application are not limited thereto.

It should also be understood that in the embodiment of the present application, when the DOE includes the tilted periodic micro-nano structure, and when three consecutive pixels on the DOE are repeated in one period, the order of the three consecutive pixels may be changed, for example, in the example shown in fig. 11, 3 consecutive pixels on the DOE sequentially diffract blue light, green light, and red light. Optionally, in this embodiment of the application, 3 consecutive pixels may also sequentially diffract blue light, red light, and green light, or green light, red light, and blue light, and the color of the corresponding pixel on the filter also changes accordingly. The embodiments of the present application are not limited thereto.

Optionally, as a possible implementation manner, for an optical lens, angles of main light angles (CRA) incident on a sensor (sensor) from different view fields are different, and solid angles of a single field angle incident on the lens are also different, where angles of edge view fields are not centrosymmetric, so that diffraction angles of DOE layers are also different, and therefore, in order to ensure that the DOE matches an actual transmission view field of a light beam, functions of the DOE may be further improved, the DOE layer may be partitioned, different regions correspond to different incident angles of light, and corresponding structural parameters of different regions are different. That is, therefore, the structural parameters on the DOE are different from each other in each Pixel (Pixel) and also different in different positions (or regions). The structural parameters include, for example: period, duty cycle, or etch depth, etc.

Optionally, in this embodiment of the application, as a possible implementation manner, since the light is centrosymmetric when being incident on the sensor, when the DOE layer is partitioned, the DOE layer may be centrosymmetric and partitioned, that is, a plurality of different regions have the same geometric center, so that an actual transmission manner of the light may be matched, complexity of partition design is reduced, and implementation is facilitated. For example, in the schematic diagram of different regions of the DOE layer provided in the embodiment of the present application shown in fig. 12, as shown in a in fig. 12, the division manner is to perform circular division with the center of the DOE layer as an origin. The b-diagram in fig. 12 shows the matrix partitions with the DOE layer center as the origin.

It should be understood that, in the embodiment of the present application, there is no limitation on the number of regions obtained after the DOE layer is partitioned.

Since the micro-nano structure (such as a grating) is related to polarization, the periodic micro-nano structure can be designed to be a 2-dimensional structure, that is, diffraction of light beams in four directions, namely up, down, left and right (or front, back, left and right) is realized by adopting the two-dimensional periodic micro-nano structure, and further, different configurations of optical elements are realized.

Fig. 13 is a schematic diagram illustrating an arrangement manner of a DOE and colors of corresponding pixels on a filter when an example of a DOE layer provided by the present application includes a two-dimensional periodic micro-nano structure. As shown in a diagram in fig. 13, 102 denotes a DOE layer, which is implemented by a two-dimensional grating structure. 1021, 1022, and 1023 on the DOE layer 102 represent different pixels on the DOE layer 102, respectively, which diffract different colors of light, with different parameters of the grating structure on different pixels. The pixel 1021 diffracts blue light and green light in four directions, namely, up, down, left, and right, and transmits red light. The pixel 1022 diffracts red and green light in four directions, up, down, left, and right, and transmits blue light. The pixel 1023 has no grating structure and does not diffract light. As shown in b diagram in fig. 13, 1012 denotes CMY filters corresponding to 102, and 10121, 10122, 10123 denote pixels of different colors on the CMY filters 1012, respectively. The pixel 10121 on the CMY filter corresponds to the pixel 1021 on the DOE layer, the pixel 10122 on the CMY filter corresponds to the pixel 1022 on the DOE layer, and the pixel 10123 on the CMY filter corresponds to the pixel 1023 on the DOE layer.

As shown in fig. 13, for the pixel 10121 on the filter, the transmitted light is red light, and the diffracted red light and green light, which are diffracted by the three pixels 1022 on the left, right, and lower (or left, right, and upper) sides, are mixed into yellow light, and thus the pixel 10121 on the filter is a yellow pixel. For the pixel 10122 on the filter, the transmitted light is blue light, and the four pixels 1021 in the up, down, left, and right directions diffract the blue light and the green light, which are mixed into cyan light, so that the pixel 10122 on the filter is a cyan pixel. Because full-color display is needed, the pixel 10123 receives the diffracted blue light and green light diffracted by the four pixels 1021 in the up-down, left-right directions, and because full-color display is needed, the pixel 10123 needs to display green, so the pixel 1023 corresponding to the pixel 10123 needs to be set as a pixel for transmitting green light, the green pixel transmits green light, and reflects or absorbs red light and blue light, so that green light can be displayed on the pixel 10123, and full-color display is realized.

Optionally, in this embodiment of the application, the DOE layer may adopt a polarization-independent periodic micro-nano structure, that is, light of different colors is diffracted on pixels of the DOE layer in the up-down, left-right directions, respectively, and only light of one color is diffracted in a certain direction. The embodiments of the present application are not limited thereto.

The optical lens provided by the application adds a layer of diffractive optical element DOE between the color filter and the infrared cut-off filter, and optionally, the DOE layer can be realized by using a grating. Through diffraction of the DOE layer to light, the light which is not transmitted by a certain pixel of the color filter is diffracted to the adjacent pixel of the color filter to be transmitted, so that the optical utilization rate is improved, and the quality of an optical lens is improved.

The application also provides a terminal device, which comprises a display screen and any one of the optical lenses provided by the embodiment of the application. The display screen is used for displaying pictures or videos shot by the optical lens.

For example, the terminal device provided in the present application may be a mobile phone with a photographing function, a Personal Digital Assistant (PDA), or a camera or a video camera, and the present application is not limited herein.

It should be understood that the above description is only for the purpose of helping those skilled in the art better understand the embodiments of the present application, and is not intended to limit the scope of the embodiments of the present application. Various equivalent modifications or changes, or combinations of any two or more of the above, may be apparent to those skilled in the art in light of the above examples given. Such modifications, variations, or combinations are also within the scope of the embodiments of the present application.

It should also be understood that the foregoing descriptions of the embodiments of the present application focus on highlighting differences between the various embodiments, and that the same or similar elements that are not mentioned may be referred to one another and, for brevity, are not repeated herein.

It should also be understood that the manner, the case, the category, and the division of the embodiments are only for convenience of description and should not be construed as a particular limitation, and features in various manners, the category, the case, and the embodiments may be combined without contradiction.

It is also to be understood that the terminology and/or the description of the various embodiments herein is consistent and mutually inconsistent if no specific statement or logic conflicts exists, and that the technical features of the various embodiments may be combined to form new embodiments based on their inherent logical relationships.

The above description is only for the specific embodiments of the present application, but the scope of the present application is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present application, and shall be covered by the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. An optical lens, comprising:

the infrared cut-off filter is used for reducing crosstalk among pixels with different colors on the color filter;

the color filter is used for filtering the received light;

and the diffractive optical element is arranged between the color filter and the infrared cut-off filter and is used for diffracting the output light of the infrared cut-off filter and transmitting the diffracted light to the color filter, so that the light of a first color, which is not transmitted on a first pixel of the color filter, is diffracted to a second pixel, the light of the first color is transmitted on the second pixel, and the second pixel is adjacent to the first pixel.

2. An optical lens according to claim 1,

the diffractive optical element comprises a periodic micro-nano structure.

3. An optical lens according to claim 2, wherein the periodic micro-nano structure is a grating.

4. An optical lens according to claim 2 or 3, wherein the consecutive 3 pixels on the diffractive optical element are repeated for one period, each of the consecutive 3 pixels diffracting light of a single color being different in color.

5. An optical lens according to claim 2 or 3, wherein 2 pixels in succession on the diffractive optical element are repeated for one period, and after M repetition periods, pixels transmitting green light are respectively present on both sides of 2 × M pixels, and each of two pixels adjacent on the diffractive optical element diffracts light of two different colors, M being a positive integer.

6. An optical lens according to any one of claims 1 to 5, characterized in that the diffractive optical element comprises a plurality of different regions on which structural parameters are different, the structural parameters comprising: at least one of a period, a duty cycle, or an etch depth.

7. An optical lens according to claim 6, characterized in that the plurality of different regions have the same geometric center.

8. An optical lens according to any one of claims 1 to 7, wherein the diffractive optical element comprises a two-dimensional periodic micro-nano structure, a third pixel on the diffractive optical element corresponds to a fourth pixel on the color filter, and light diffracted by the third pixel is transmitted to pixels above, below, to the left and to the right adjacent to the fourth pixel.

9. An optical lens according to any one of claims 1 to 8, further comprising a microlens disposed between the color filter and the ir cut filter, the diffractive optical element being disposed between the microlens and the ir cut filter.

10. An optical lens according to any one of claims 1 to 8, further comprising a microlens disposed between the color filter and the infrared cut filter, the diffractive optical element being disposed between the microlens and the color filter.

11. An optical lens according to claim 10, wherein an adhesive layer is provided between the diffractive optical element and the color filter.

12. The optical lens according to any one of claims 1 to 11,

the light of the first color is any one of red light, blue light or green light; or,

the light of the first color is blue light and green light, or red light and green light.

13. An optical lens according to any one of claims 1 to 12, wherein the color filter is a red/green/blue filter or a cyan/magenta/yellow filter.

14. A terminal device comprising an optical lens of any one of claims 1-13 and a display screen for displaying a photograph or video taken by the optical lens.