electronic devices

Abstract

This application discloses an electronic device, belonging to the field of electronic device technology. The electronic device includes: a screen; and a lens, the lens comprising a body and multiple protrusions, the body being disposed opposite to the screen, the protrusions being located on the side of the body closer to the screen, each protrusion forming a microlens, and the multiple microlenses being combined to form a microlens array; wherein, among the multiple microlenses, at least two microlenses have different optical parameters, the optical parameters including at least one of radius of curvature and conic coefficient.

Description

Technical Field

[0001] This application belongs to the field of electronic equipment technology, and specifically relates to an electronic device. Background Technology

[0002] Head-mounted VR (Virtual Reality) devices require the display to be close to the eyes, so in order to maintain the perceived quality of the image (reduce screen artifacts such as the screen door effect), optical lenses need to be inserted in a limited space to improve the device's resolution.

[0003] In related technologies, in order to solve the problem of image quality degradation caused by chromatic aberration of refractive lenses, multiple lenses with different refractive indices and different light-receiving surfaces are required to improve chromatic aberration.

[0004] However, increasing the number of lenses will inevitably increase the size and weight of the head-mounted VR device, and users are quite sensitive to the weight of the head-mounted VR device, resulting in technical problems such as strong pressure when wearing the head-mounted VR device and poor user experience. Summary of the Invention

[0005] This application aims to provide an electronic device that at least solves the technical problems of strong pressure when wearing head-mounted VR devices and poor user experience.

[0006] To solve the above-mentioned technical problems, this application is implemented as follows:

[0007] In a first aspect, embodiments of this application propose an electronic device, which includes: a screen; a lens, the lens including a body and a plurality of protrusions, the body being disposed opposite to the screen, the protrusions being disposed on the side of the body close to the screen, each protrusion forming a microlens, and the plurality of microlenses being combined to form a microlens array; wherein, among the plurality of microlenses, at least two microlenses have different optical parameters, the optical parameters including at least one of radius of curvature and conic coefficient.

[0008] This application achieves a segmented design of the light-receiving surface of the lens by setting multiple protrusions on the light-receiving side of the body. Based on this, different segmented areas are designed with different optical parameters to change the focusing direction of light of different wavelengths. This helps to reduce the dispersion amplitude of the light emitted through the lens, reduce the color difference between the image observed by the user and the actual image to be displayed, and thus improve the quality of the image observed by the user.

[0009] Furthermore, compared to the existing technology's solution of stacking multiple lenses, this application solves the dispersion problem through a segmented design on a single lens, without increasing the number of lenses between the user and the screen. The size and weight of the electronic device do not need to be increased accordingly, thus solving the technical problems of strong pressure when wearing the device and poor user experience in related technologies. This achieves the technical effects of optimizing the lens structure, providing convenient conditions for the miniaturization and lightweight design of electronic devices, and improving the wearing comfort of electronic devices.

[0010] On the other hand, the lens block design proposed in this application has solved the color difference problem caused by dispersion at the physical level. Electronic devices no longer need to perform a lot of anti-dispersion processing in advance through color difference correction algorithms, thereby freeing up the computing power of electronic devices, reducing the possibility of electronic devices experiencing stuttering and delay, and thus achieving the technical effect of reducing the power consumption of electronic devices and optimizing the user experience of electronic devices.

[0011] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0012] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0013] Figure 1 This is a schematic diagram of the structure of an electronic device according to an embodiment of this application;

[0014] Figure 2 yes Figure 1 The electronic device in the illustrated embodiment is Figure 1 Optical path diagram of region A in the middle;

[0015] Figure 3 yes Figure 1 The electronic device in the illustrated embodiment is Figure 1 Optical path diagram of region B in the middle;

[0016] Figure 4 This is a schematic diagram of the structure of an electronic device according to an embodiment of this application;

[0017] Figure 5 This is a schematic diagram of the structure of an electronic device according to an embodiment of this application;

[0018] Figure 6 This is a schematic diagram of the structure of an electronic device according to an embodiment of this application.

[0019] Figure label:

[0020] 100 Electronic device, 110 Screen, 120 Lens, 122 Body, 124 Protrusion, 126 Microlens, 1262 First microlens, 1264 Second microlens, 1266 Third microlens, 128 Microlens array. Detailed Implementation

[0021] The embodiments of this application will now be described in detail. Examples of these embodiments are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0022] The terms "first" and "second" in the specification and claims of this application may explicitly or implicitly include one or more of the features. In the description of this application, unless otherwise stated, "multiple" means two or more. Furthermore, "and / or" in the specification and claims indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0023] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0024] The following is combined Figures 1 to 6 This application describes an electronic device 100 according to an embodiment of the present application.

[0025] like Figure 1 , Figure 2 , Figure 3 and Figure 4 As shown, according to some embodiments of this application, an electronic device 100 includes: a screen 110; a lens 120, the lens 120 including a body 122 and a plurality of protrusions 124, the body 122 being disposed opposite to the screen 110, the protrusions 124 being disposed on the side of the body 122 near the screen 110, each protrusion 124 forming a microlens 126, and the plurality of microlenses 126 being combined to form a microlens array 128; wherein, among the plurality of microlenses 126, at least two microlenses 126 have different optical parameters, the optical parameters including at least one of radius of curvature and conic coefficient.

[0026] This application defines an electronic device 100 that utilizes the refraction principle of an optical lens to change the direction of light, focusing a screen 110 close to the human eye and simultaneously magnifying the image size of the screen 110, providing the user with a wider field of view and an immersive experience similar to a giant screen cinema. Specifically, the electronic device 100 can be a head-mounted VR headset.

[0027] The electronic device 100 includes a screen 110 and a lens 120. The screen 110 is the light-emitting structure of the electronic device 100, and the screen 110 can display the image information required by the user. The lens 120 is disposed opposite to the screen 110, and the light-emitting sides of the lens 120 and the screen 110 are spaced apart. When the user wears the electronic device 100 correctly, the lens 120 is located between the screen 110 and the user's eyes. The lens 120 can expand the user's field of view through the principle of refraction, allowing the user to observe clear and magnified image information.

[0028] During refraction, light inevitably undergoes chromatic aberration, resulting in a color difference between the image observed by the user and the actual image, impacting the user experience. To address this, related technologies employ both structural and algorithmic solutions. Structural solutions use multiple lenses stacked between the eye and the display to alter the light path, reducing aberration. However, increasing the number of lenses increases the product's size and weight, leading to greater pressure on the user. Algorithmic solutions utilize pre-processing with chromatic aberration correction algorithms to pre-correct color differences before the image is output to the display. However, this computational compensation process requires significant power, increasing power consumption and potentially causing image latency.

[0029] In this application, the lens 120 includes a body 122 and protrusions 124. The side of the body 122 facing the screen 110 is the light-receiving side. Multiple protrusions 124 are provided on the light-receiving side of the body 122, and each protrusion 124 is outwardly convex. Each protrusion 124 can form a microlens 126 on the light-receiving side of the body 122. The multiple microlenses 126 formed by the multiple protrusions 124 are combined on the light-receiving side of the body 122 to form a microlens array 128. Furthermore, among the multiple microlenses 126, at least two microlenses 126 are designed with different optical parameters. Different optical parameters correspond to different wavelengths, and the two microlenses 126 designed with different optical parameters can change the focusing position of light of the corresponding wavelength through refraction.

[0030] in, Figure 2 and Figure 3In the diagram, arrow a shows the incident light rays directed toward the light-receiving side, and arrow b shows the outgoing light rays emitted from the backlight side of lens 120. Figure 3 The middle arrow c indicates the direction of change in the focusing position of the emitted light.

[0031] The optical parameters include at least one of the radius of curvature and the conic coefficient. Changing at least one of the radius of curvature and the conic coefficient can change the wavelength adapted to the microlens 126, enabling it to specifically change the focusing position of light of a certain wavelength. It should be noted that the optical parameters include not only the radius of curvature and / or the conic coefficient, but other optical parameters can also be introduced to change the dispersion and improve the effect.

[0032] As can be seen, this application achieves a segmented design of the light-receiving surface of the lens 120 by setting multiple protrusions 124 on the light-receiving side of the body 122. Based on this, different segmented areas are designed with different optical parameters to change the focusing direction of different wavelengths of light, thereby reducing the dispersion amplitude of the light emitted through the lens 120, reducing the color difference between the image observed by the user and the actual image to be displayed, and thus improving the quality of the image observed by the user.

[0033] Furthermore, compared to the solution of stacking multiple lenses in related technologies, this application solves the dispersion problem by using a segmented design on a single lens 120. This does not increase the number of lenses 120 between the user and the screen 110, and the size and weight of the electronic device 100 do not need to be increased accordingly. This solves the technical problems of strong pressure when wearing the device and poor user experience in related technologies. In turn, it achieves the technical effects of optimizing the structure of the lens 120, providing convenient conditions for the miniaturization and lightweight design of the electronic device 100, and improving the wearing comfort of the electronic device 100.

[0034] On the other hand, the 120-segment lens design proposed in this application has solved the color difference problem caused by dispersion at the physical level. The electronic device 100 no longer needs to perform a lot of anti-dispersion processing in advance through the color difference correction algorithm, thereby freeing up the computing power of the electronic device 100, reducing the possibility of the electronic device 100 experiencing stuttering and delay, and thus achieving the technical effect of reducing the power consumption of the electronic device 100 and optimizing the user experience of the electronic device 100.

[0035] like Figure 4 and Figure 5 As shown, in some embodiments, optionally, the microlens 126 is a regular polygon on the side of the body 122 near the screen 110.

[0036] In this embodiment, when the lens 120 is viewed from the light-receiving side, the microlens 126 formed by the protrusion 124 on the body 122 is a regular polygon, specifically including a regular square, a regular pentagon, or a regular hexagon.

[0037] By designing the microlens 126 as a regular polygon, a regular and uniform microlens array 128 can be formed on the light-receiving side of the lens 120, optimizing the segmented design effect of the light-receiving side of the lens 120 and improving the chromatic aberration improvement effect of the lens 120. On the other hand, designing the microlens 126 as a regular polygon can reduce the processing difficulty or mold complexity of the lens 120, thereby reducing the process complexity and production cost of the lens 120.

[0038] like Figure 4 and Figure 5 As shown, in some embodiments, the microlens 126 may optionally be square or hexagonal.

[0039] In this embodiment, the microlens 126 is square or hexagonal.

[0040] Figure 4 As can be seen, each microlens 126 in the microlens array 128 is a regular hexagon, and each microlens 126 has the same size. Multiple regular hexagonal microlenses 126 are spliced ​​together to form the microlens array 128.

[0041] Figure 5 As can be seen, each microlens 126 in the microlens array 128 is a regular quadrilateral, and each microlens 126 has the same size. Multiple regular quadrilateral microlenses 126 are spliced ​​together to form the microlens array 128.

[0042] Therefore, by designing the microlens 126 as a regular square or regular hexagon, multiple microlenses 126 can be tightly spliced ​​together, eliminating the gap between two adjacent microlenses 126, thereby improving the coverage of the microlens array 128 on the light-receiving side of the lens 120, avoiding dead angles in chromatic aberration improvement on the lens 120, and thus achieving the technical effect of improving the chromatic aberration improvement effect of the lens 120 and optimizing the user experience.

[0043] like Figure 1 , Figure 4 and Figure 5 As shown, in some embodiments, optionally, the side length of the microlens 126 is L, and the maximum size of the orthographic projection of the lens 120 is D, the side length and the maximum size satisfying the following formula:

[0044] K = L ÷ D; (1)

[0045] K≤1÷(3×n); (2)

[0046] Where K is the segmentation coefficient of microlens 126, and n is a positive integer.

[0047] In this embodiment, the side length of the hexagonal microlens 126 or the square microlens 126 is L. The shape of the lens 120 can be obtained by orthographic projection of the lens 120, and the maximum size D can be obtained on the orthographic projection.

[0048] For example, Figure 4 and Figure 5 This is a front view of a circular lens 120. The shape of the orthographic projection of the circular lens 120 corresponds to the outer contour of the circle in this front view. The orthographic projection of the circular lens 120 has the same size in all directions, and the maximum size D is the diameter.

[0049] For example, such as Figure 6 This is a front view of a square lens 120. The shape of the orthographic projection of the square lens 120 corresponds to the outer contour of the rectangle in this front view. The maximum dimension D of the orthographic projection of the square lens 120 is the diagonal dimension.

[0050] Based on this, the ratio of side length L to maximum size D is the segmentation coefficient K of microlens 126. Specifically, the segmentation coefficient K of microlens 126 is ≤ 1 ÷ (3 × n), where n is a positive integer. The segmentation coefficient is used to determine the number of microlenses 126 that need to be arranged on the body 122, and the specific number of microlenses 126 is positively correlated with the value of K. During the design process, the final number of microlenses 126 needs to be determined by combining the value of K and the actual parameter requirements.

[0051] By defining the shape and number of microlenses 126 using the above formulas (1) and (2), the effect of microlenses 126 on improving the dispersion problem can be enhanced, thereby reducing the color difference of the image observed by the user, and thus achieving the technical effect of improving the image display effect of electronic device 100 and enhancing the user experience.

[0052] In some embodiments, optionally, a three-dimensional coordinate system is established with the thickness direction of the lens 120 as the Z-axis. The formula for calculating the surface profile of the microlens 126 in this three-dimensional coordinate system is as follows:

[0053]

[0054] in, X These are the coordinate values ​​along the X-axis. Y The coordinate value is along the Y-axis. z(X,Y) coordinates (X,Y) The dimensions of lens 120 in the Z-axis direction Rx Let be the radius of curvature of microlens 126 in the X-axis direction. RyLet be the radius of curvature of microlens 126 along the Y-axis. Cx Here is the conicity of microlens 126 in the X-axis direction. Cy is the conicity coefficient of microlens 126 in the Y-axis direction.

[0055] In this embodiment, the lens 120 is placed in a three-dimensional coordinate system. Specifically, the Z-axis of the three-dimensional coordinate system corresponds to the thickness direction of the lens 120, and the X-axis and Y-axis of the three-dimensional coordinate system correspond to the length and width of the lens 120, respectively. The shape of the lens 120 can be determined by the coordinate values ​​in this three-dimensional coordinate system.

[0056] Microlenses 126 at different positions can be optimized for different center wavelengths, and two microlenses 126 with the same design parameters are spaced apart from each other. The position of each microlens 126 on the body 122 is different, and the different optical design parameters such as the radius of curvature are manifested in different designs for different center wavelengths.

[0057] Specifically, taking the microlens 126 as a regular hexagon or a regular square as an example, the surface shape of the lens 120 can be designed according to the above formula (3). By dividing the multiple microlenses 126 into sections, it is equivalent to cutting the light-receiving side of the lens 120 into a fine design. Different sections formed by different optical parameters are used to adjust the focusing position of different wavelengths of light to achieve color difference optimization. This helps to reduce the dispersion amplitude of the light emitted through the lens 120, reduce the color difference between the image observed by the user and the image to be displayed, thereby improving the quality of the image observed by the user.

[0058] Furthermore, the surface shape calculation formula (3) can be used in conjunction with automated processing equipment to achieve automated processing of lens 120 or automated processing of injection mold, thereby achieving the technical effect of improving the production efficiency of lens 120 and improving the forming accuracy of lens 120.

[0059] In some embodiments, the surface of the protrusion 124 is optionally centrally symmetrical.

[0060] In this embodiment, when Rx = Ry , Cx = Cy When the microlens 126 is designed, it has a centrally symmetrical shape; otherwise, the surface of the microlens 126 is an irregular free-form surface.

[0061] The centrally symmetrical microlens 126 is more conducive to the processing and forming of the surface, which helps to reduce the difficulty of machining the microlens 126 and the structural complexity of the mold, thereby achieving the technical effect of reducing the processing difficulty of lens 120 and reducing the production cost of lens 120.

[0062] In some embodiments, the body 122 and the protrusion 124 are optionally an integral structure.

[0063] In this embodiment, the body 122 and the protrusion 124 are an integral structure. In the lens 120 with an integral structure, there is no structural cross section between the body 122 and the protrusion 124, which will not affect the transmission direction of the light path, thereby ensuring that the lens 120 can effectively form an image and effectively reduce the chromatic aberration of the image.

[0064] Furthermore, manufacturing the lens 120 using an integral molding process can reduce the processing difficulty and complexity of the lens 120, which is conducive to improving the production efficiency of the lens 120 and reducing the production cost of the lens 120.

[0065] like Figure 4 and Figure 5 As shown, in some embodiments, optionally, among the plurality of microlenses 126, at least two microlenses 126 with the same optical parameters are included; the two microlenses 126 with the same optical parameters are distributed at intervals in the microlens array 128.

[0066] In this embodiment, the microlens array 128 is divided into multiple microlenses 126 by optical parameters, wherein at least two microlenses 126 designed with the same set of optical parameters belong to the same type of microlens 126. Based on this, the two microlenses 126 of the same type are distributed at intervals in the microlens array 128, and at least one non-identical microlens 126 with different optical parameters is interspersed between the two microlenses 126 of the same type, so that multiple types of microlenses 126 can be interspersed and separated in the microlens array 128.

[0067] By designing the microlens array 128 in an interleaved distribution manner, the uniformity of the lens 120 in optimizing the dispersion problem can be improved, avoiding significant differences in the dispersion optimization amplitude between different areas of the lens 120, making the final image quality more uniform, and thus achieving the technical effect of improving the imaging quality of the electronic device 100 and enhancing the user experience.

[0068] like Figure 4 and Figure 5 As shown, in some embodiments, optionally, the plurality of microlenses 126 include a first microlens 1262, a second microlens 1264, and a third microlens 1266; the first radius of curvature and the first conic coefficient of the first microlens 1262 correspond to the center wavelength of red light; the second radius of curvature and the second conic coefficient of the second microlens 1264 correspond to the center wavelength of green light; and the third radius of curvature and the third conic coefficient of the third microlens 1266 correspond to the center wavelength of blue light.

[0069] In this embodiment, the plurality of microlenses 126 include three types of microlenses 126: a first microlens 1262, a second microlens 1264, and a third microlens 1266. The three types of microlenses 126 correspond to the red, green, and blue color channels in the RGB color mode, respectively.

[0070] Specifically, the first radius of curvature and the first conic coefficient of the first microlens 1262 correspond to the center wavelength of red light. The first microlens 1262 can change the focusing position of the red light incident on the lens, thereby reducing the dispersion amplitude of the red light. Correspondingly, the second radius of curvature and the second conic coefficient of the second microlens 1264 correspond to the center wavelength of green light. The second microlens 1264 can change the focusing position of the green light incident on the lens, thereby reducing the dispersion amplitude of the green light. The third radius of curvature and the third conic coefficient of the third microlens 1266 correspond to the center wavelength of blue light. The third microlens 1266 can change the focusing position of the blue light incident on the lens, thereby reducing the dispersion amplitude of the blue light. Thus, starting from the three primary colors, the dispersion problem of the lens 120 is improved, the chromatic aberration of the image is reduced, and ultimately, the imaging quality of the electronic device 100 is improved, optimizing the user experience.

[0071] Specifically, the number of types of microlenses 126 can be increased based on the first microlens 1262, the second microlens 1264 and the third microlens 1266. For example, microlenses 126 corresponding to the center wavelength of yellow light can be added to further enhance the dispersion improvement effect and imaging quality of the lens 120.

[0072] like Figure 4 and Figure 5 As shown, in some embodiments, optionally, the first microlens 1262, the second microlens 1264 and the third microlens 1266 are uniformly distributed on the body 122.

[0073] In this embodiment, among the first microlens 1262, the second microlens 1264, and the third microlens 1266, two microlenses 126 of the same type are spaced apart in the microlens array 128, and at least one dissimilar microlens 126 with different optical parameters is interspersed between the two identical microlenses 126, so that multiple microlenses 126 can be interspersed and separated in the microlens array 128. Furthermore, the first microlens 1262, the second microlens 1264, and the third microlens 1266 are uniformly distributed on the body 122.

[0074] By designing the microlens array 128 using interleaved and uniform distribution methods, the uniformity of the lens 120 in optimizing chromatic aberration can be improved, avoiding significant differences in chromatic aberration optimization amplitude between different areas of the lens 120. This results in a more consistent final image quality, thereby improving the imaging quality of the electronic device 100 and enhancing the user experience.

[0075] The electronic device 100 can be a terminal or other devices besides a terminal. For example, the electronic device 100 can be a mobile phone, tablet computer, laptop computer, handheld computer, vehicle-mounted electronic device 100100, mobile internet device (MID), augmented reality (AR) / virtual reality (VR) device, robot, wearable device, ultra-mobile personal computer (UMPC), netbook, or personal digital assistant (PDA), etc. It can also be a personal computer (PC), television (TV), ATM, or self-service machine, etc. The embodiments of this application do not specifically limit it.

[0076] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0077] Although embodiments of this application have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of this application, the scope of which is defined by the claims and their equivalents.

Claims

1. An electronic device, comprising: The electronic device comprises: a screen; a lens comprising a body and a plurality of protrusions, the body being arranged opposite to the screen, the protrusions being arranged on a side of the body close to the screen, each of the protrusions forming a microlens, and the plurality of microlenses combining to form a microlens array; wherein at least two of the plurality of microlenses have different optical parameters, the optical parameters including at least one of a radius of curvature and a conic constant; the plurality of microlenses including a first microlens, a second microlens, and a third microlens; the first microlens having a first radius of curvature and a first conic constant corresponding to a central wavelength of red light; the second microlens having a second radius of curvature and a second conic constant corresponding to a central wavelength of green light; the third microlens having a third radius of curvature and a third conic constant corresponding to a central wavelength of blue light; the first microlens, the second microlens, and the third microlens being uniformly distributed on the body.

2. The electronic device according to claim 1, wherein: the microlenses on the side of the body close to the screen are regular polygons.

3. The electronic device of claim 2, wherein, The microlenses are regular quadrilaterals or regular hexagons.

4. The electronic device according to claim 2, wherein: a side length of the microlenses is L, a maximum dimension of a front projection of the lens is D, the side length and the maximum dimension satisfy the following formula: K = L ÷ D; K ≤ 1 ÷ (3 × n); wherein K is a cutting coefficient of the microlenses, and n is a positive integer.

5. The electronic device according to claim 1, wherein: a three-dimensional coordinate system is established with a thickness direction of the lens as a Z axis, and a surface type of the microlenses in the three-dimensional coordinate system is calculated according to the following formula: wherein is a coordinate value in the X-axis direction, is a coordinate value in the Y-axis direction, is a coordinate is a dimension of the lens in the Z-axis direction at the point, is a radius of curvature of the microlens in the X-axis direction, is a radius of curvature of the microlens in the Y-axis direction, is a conic constant of the microlens in the X-axis direction, is a conic constant of the microlens in the Y-axis direction.

6. The electronic device according to claim 1, wherein: a surface of the protrusions is centrally symmetric.

7. The electronic device according to claim 1, wherein: the body and the protrusions are of an integrated structure.

8. The electronic device according to any one of claims 1 to 7, wherein: at least two of the plurality of microlenses have the same optical parameters; the two microlenses with the same optical parameters are distributed at intervals in the microlens array.

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