CN215297723U - Optical element, camera module and electronic equipment - Google Patents

Abstract

The application relates to an optical element, a camera module and electronic equipment, wherein the optical element comprises a lens base layer, a micro-lens structure and a Fresnel lens, and the lens base layer is provided with a first surface and a second surface opposite to the first surface; the micro-lens structure comprises a plurality of micro-lenses which are arranged on the first surface in an array mode, and the curvatures of the micro-lenses with different distances from the center of the first surface are different; the Fresnel lens is arranged on the second surface. In the optical element of this application, through set up the microlens structure including a plurality of microlenses on the first surface at lens basic unit, fresnel lens on the second surface of cooperation lens basic unit images, and in the microlens structure, the camber of the microlens of the centre interval difference apart from the first surface is different, can all play fine receipts light effect to the light of optical element different positions department, under the prerequisite that keeps less thickness, can make optical element also have better formation of image effect under the wide-angle scene, the definition of formation of image is high.

Description

Optical element, camera module and electronic equipment

Technical Field

The application relates to the technical field of optical components, in particular to an optical element, a camera module and electronic equipment.

Background

In recent years, with the development of multimedia technology, lenses are used more and more widely, and the lenses are provided in digital cameras, video cameras, mobile phones and other devices so as to meet the shooting requirements of people at any time and any place. In order to enhance the light receiving effect of the lens, the lens can have higher definition in a large-angle scene and can clearly image, the lens in the related art generally adopts a design of stacking a plurality of lenses, and the problem exists that the lens is thicker and occupies a large space.

SUMMERY OF THE UTILITY MODEL

Accordingly, it is desirable to provide an optical element, an image pickup module, and an electronic apparatus, which solve the problems of a thick image pickup module and a large occupied space.

An embodiment of the present application provides an optical element, including: a lens base layer having a first surface and a second surface opposite to the first surface; a microlens structure including a plurality of microlenses arranged in an array on a first surface, the microlenses having different distances from a center of the first surface and different curvatures; and the Fresnel lens is arranged on the second surface.

Based on above-mentioned embodiment, through set up the microlens structure including a plurality of microlenses on the first surface at lens basic unit, the fresnel lens on the second surface of cooperation lens basic unit images, and in the microlens structure, the camber of the microlens different from the centre-to-centre spacing of first surface is different, because the microlens of different curvatures has different refraction effect to light, can all play fine receipts light effect to the light of optical element different positions department, under the prerequisite that keeps less thickness, can make optical element also have better formation of image effect under to the wide-angle scene, the definition of formation of image is high.

In one embodiment, the curvature of the microlenses at the central position away from the first surface is greater than the curvature of the microlenses at the central position near the first surface.

Based on the above embodiment, by making the curvature of the microlens at the central position far from the first surface larger than the curvature of the microlens at the central position near the first surface, that is, in the optical element, the curvature of the microlens at the position closer to the outer edge thereof is larger, the light-collecting effect for the light ray having a larger degree of deflection at the position of the outer edge is relatively stronger, and the curvature of the microlens at the position closer to the central position thereof is smaller, the light-collecting effect for the light ray having a smaller degree of deflection at the central position is relatively weaker, so that clear imaging can be realized for the light rays everywhere on the optical element.

In one embodiment, the microlenses are arranged in an annular array on the first surface such that lines connecting the centers of the microlenses form a plurality of concentric circles centered at the center of the first surface.

Based on the above embodiment, by arranging the plurality of microlenses on the first surface in an annular array, the processing and manufacturing of the optical element are facilitated, and the microlenses are distributed on the first surface more densely and uniformly, so that light rays passing through different positions on the optical element can pass through the microlenses, the imaging of the optical element is more uniform, and the imaging definition of the optical element is further improved.

In one embodiment, the microlenses located on the same concentric circle have the same curvature, and the microlenses located on different concentric circles have different curvatures.

Based on the above embodiment, because the distances from the different microlenses located on the same concentric circle to the center of the first surface are all equal, and the deflection degrees of the light rays at the corresponding positions when the light rays pass through the optical element are all equal, the microlenses with the same curvature can achieve the light receiving effect of the same degree on the light rays, so that the light rays passing through the optical element are more uniform. And the micro-lenses on different concentric circles are not equal to the central distance from the first surface, and the deflection degrees of the light rays at the corresponding positions when the light rays pass through the optical element are different, so that the micro-lenses with different curvatures respectively play different light receiving effects on the light rays, and the different positions on the optical element can have better imaging effects.

In one embodiment, the fresnel lens includes a central lens located at a central position of the second surface, and a plurality of annular lenses arranged in an annular array around the central lens.

Based on the above embodiment, the fresnel lens is configured to include the central lens located at the central position of the second surface and the plurality of annular lenses arranged in an annular array around the central lens, that is, as much optical material as possible is removed from the second surface of the lens base layer, only the bending degree of the lens base layer is maintained, and on the premise that the imaging effect of the fresnel lens is not affected, the fresnel lens is made to be lighter and thinner, and the thickness of the optical element is further reduced.

In one embodiment, the annular lenses are arranged in one-to-one correspondence with concentric circles.

Based on the above embodiment, the plurality of annular lenses arranged around the central lens in the fresnel lens are arranged in the annular array and correspond to the plurality of concentric circles formed by the connecting lines of the centers of the microlenses in the microlens structure one by one, so that in the use process of the optical element, the light passing through each annular lens of the fresnel lens can enter the microlenses on the corresponding concentric circles in the microlens structure and is received by the microlenses, and the imaging uniformity of the optical element is improved on the premise of improving the imaging effect of the optical element.

In one embodiment, the orthographic projection of the microlens on the second surface falls entirely within the corresponding annular lens.

Based on the above embodiment, the orthographic projection of the micro lens on the second surface completely falls into the corresponding annular lens, that is, the plurality of annular lenses arranged around the central lens annular array in the fresnel lens can completely cover the micro lens at the corresponding position in the micro lens structure, so that each micro lens can accurately receive light rays passing through different positions of the fresnel lens, and the situation of imaging errors caused by the fact that light rays with different deflection degrees enter the same micro lens can not occur, thereby ensuring the imaging stability of the optical element.

The embodiment of the application further provides a camera shooting module, which includes: an optical element as described above; and a photosensitive element disposed opposite to the optical element.

Based on above-mentioned embodiment, through adopting optical element as above, under the prerequisite of keeping less thickness, can make the module of making a video recording also have better formation of image effect under to the wide-angle scene, the imaging definition is high.

In one embodiment, the first surface of the lens substrate faces the photosensitive element.

Based on the above embodiment, since the microlens structure is disposed on the first surface, and the fresnel lens is disposed on the second surface, the light passing through each annular lens of the fresnel lens can enter the corresponding microlens on the concentric circle in the microlens structure, and is collected by the microlens, so that the first surface of the lens base layer faces the photosensitive element, that is, the first surface is used as the light exit surface of the optical element in the camera module, and the second surface is used as the light entrance surface of the optical element, which enables the optical element to have a better imaging effect in a large-angle scene, and has a high imaging definition.

An embodiment of the present application further provides an electronic device, including: the camera module is provided.

Based on above-mentioned embodiment, through adopting the module of making a video recording as above, under the prerequisite that keeps less thickness, can make electronic equipment also have better formation of image effect under to the wide-angle scene, the imaging definition is high.

Optical element based on this application embodiment, module and electronic equipment make a video recording, through set up the microlens structure including a plurality of microlenses on the first surface at lens basic unit, the fresnel lens on the second surface of cooperation lens basic unit images, and in the microlens structure, the curvature of the microlens different from the centre-to-centre spacing of first surface is different, because the microlens of different curvatures has different refraction effect to light, can all play fine receipts light effect to the light of optical element different positions department, under the prerequisite that keeps less thickness, can make optical element also have better formation of image effect under to the wide-angle scene, the definition of formation of image is high.

Drawings

FIG. 1 is a schematic diagram of a full-section structure of an optical element according to an embodiment of the present disclosure;

FIG. 2 is a schematic diagram of a microlens structure on a first surface of an optical element according to one embodiment of the present application;

FIG. 3 is a schematic diagram of a Fresnel lens on the second surface of the optical element according to an embodiment of the present disclosure;

fig. 4 is a schematic full-section structural diagram of a camera module according to an embodiment of the present application.

Detailed Description

In order to make the aforementioned objects, features and advantages of the present application more comprehensible, embodiments accompanying the present application are described in detail below with reference to the accompanying drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application. This application is capable of embodiments in many different forms than those described herein and that modifications may be made by one skilled in the art without departing from the spirit and scope of the application and it is therefore not intended to be limited to the specific embodiments disclosed below.

It will be understood that when an element is referred to as being "secured to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present.

Unless defined otherwise, technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein in the description of the present application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

In the related art, in order to enhance the light receiving effect of the lens and enable the lens to have high definition even in a large-angle scene and to clearly image, an optical element in the lens generally adopts a design of stacking a plurality of lenses, and the problem is that the thickness of the optical element is thick and the occupied space is large.

Fig. 1 is a schematic full-section structural diagram of an optical element 100 provided in an embodiment of the present application, fig. 2 is a schematic diagram of a microlens structure 120 on a first surface 111 of the optical element 100 provided in an embodiment of the present application, and fig. 3 is a schematic structural diagram of a fresnel lens 130 on a second surface 112 of the optical element 100 provided in an embodiment of the present application.

In order to at least partially solve the above problem, referring to fig. 1 to 3, an embodiment of the present application provides an optical element 100, where the optical element 100 includes a lens base layer 110, a microlens structure 120, and a fresnel lens 130. The optical element 100 is a basic unit in an optical system, is a component used for imaging or cooperating with imaging in a camera module, and is generally made of a transparent optical material.

The lens substrate 110 has a first surface 111 and a second surface 112 opposite to the first surface 111. The lens substrate 110 is a substrate for carrying other components of the optical element 100. In order to facilitate the arrangement of other components to realize the optical imaging function of the optical element 100, and reduce the size occupied by the lens base layer 110, the lens base layer 110 may be configured as a plano lens without diopter, in which both sides of the plano lens are flat, and then any one of the flat surfaces on the lens base layer 110 is the first surface 111, and the other flat surface opposite to the first surface 111 is the second surface 112.

The microlens structure 120 not only has the basic functions of focusing, imaging, etc. of the conventional lens, but also has the characteristics of small unit size and high integration, so that it can perform functions that the conventional optical element 100 cannot perform, and can constitute many novel optical systems. The microlens structure 120 may include a plurality of light-transmitting structures connected to each other, or may include a plurality of light-transmitting structures formed independently of each other. Specifically, as shown in fig. 2, in some embodiments, the microlens structure 120 includes a plurality of microlenses 121 arranged in an array on the first surface 111, and the number and arrangement of the microlenses 121 can be adjusted according to the usage scenario of the optical element 100. In the microlens structure 120, curvatures of the microlenses 121 having different pitches from the center of the first surface 111 are different. The curvature of the lens is a numerical value mathematically indicating the degree of curvature of the curved surface of the lens at a certain point, and the larger the curvature of the microlens 121, the larger the degree of projection or depression of the microlens 121, and conversely, the smaller the curvature of the microlens 121, the smaller the degree of projection or depression of the microlens 121. In the microlens structure 120 of the embodiment of the application, if the distance between the centers of any two different microlenses 121 and the first surface 111 is different, the curvatures of the two microlenses 121 are also different. Since the lens substrate 110 is generally of a regular structure, the center of the first surface 111 is its centroid. As shown in fig. 1 to 3, in the present embodiment, the lens substrate 110 is a cylinder structure, and the first surface 111 is a circle, and the center of the first surface 111 is the center of the circle. There may or may not be a specific correspondence between the center distance of the microlenses 121 from the first surface 111 and the curvature of the microlenses 121, such as a linear correspondence. The micro lenses 121 with different curvatures have different refraction effects on light, and the light at different positions of the optical element 100 can be well received by reasonably setting the curvatures of the micro lenses 121 at different positions.

Meanwhile, the fresnel lens 130 is disposed on the second surface 112 of the lens substrate 110. As shown in fig. 3, the fresnel lens 130, also known as a screw lens, is a lighter and thinner lens made by removing as much optical material as possible from a normal lens and only preserving the curvature of the optical surface of the normal lens. It is also understood that the continuous surface portion of the ordinary lens is made by collapsing it onto a flat surface. The fresnel lens 130 may be made of an optical material such as glass, resin, or silicon. The fresnel lens 130 is disposed on the second surface 112, so that the optical element 100 can have the light transmission and imaging effects of the lens while keeping the thickness small.

In the optical element 100 in this embodiment, the microlens structure 120 including the plurality of microlenses 121 is disposed on the first surface 111 of the lens base layer 110, and the fresnel lens 130 on the second surface 112 of the lens base layer 110 is used for imaging, and in the microlens structure 120, the curvatures of the microlenses 121 having different distances from the center of the first surface 111 are different, because the microlenses 121 having different curvatures have different refraction effects on light, a good light-collecting effect can be achieved on light at different positions of the optical element 100, on the premise of keeping a small thickness, the optical element 100 can have a good imaging effect in a large-angle scene, and the imaging definition is high.

As described above, the curvature of the microlenses 121 at different positions can be set properly, so as to achieve a good light-collecting effect for the light rays at different positions of the optical element 100. Therefore, in some embodiments, the curvature of the microlenses 121 at the central position away from the first surface 111 is greater than the curvature of the microlenses 121 at the central position near the first surface 111. By making the curvature of the microlens 121 at the position far from the center of the first surface 111 larger than the curvature of the microlens 121 at the position near the center of the first surface 111, that is, in the optical element 100, the larger the curvature of the microlens 121 at the position closer to the outer edge thereof, the stronger the light-collecting effect on the light ray having a larger degree of deflection at the position of the outer edge is, and the smaller the curvature of the microlens 121 at the position closer to the center thereof, the weaker the light-collecting effect on the light ray having a smaller degree of deflection at the position of the center is, the clear image formation can be achieved for the light rays everywhere on the optical element 100.

In order to enable the microlens structure 120 to cover a larger area on the first surface 111, in some embodiments, referring to fig. 2, a plurality of microlenses 121 are arranged in an annular array on the first surface 111, such that a line connecting centers of the microlenses 121 forms a plurality of concentric circles 122 centered on the center of the first surface 111. By arranging the plurality of microlenses 121 on the first surface 111 in an annular array, the processing and manufacturing of the optical element 100 are facilitated, and the microlenses 121 are distributed on the first surface 111 more densely and uniformly, so that light rays passing through different positions on the optical element 100 can pass through the microlenses 121, the image of the optical element 100 is more uniform, and the image definition of the optical element 100 is further improved.

Further, when the microlenses 121 are arranged in a circular array on the first surface 111, the curvatures of the microlenses 121 located on the same concentric circle 122 are the same, and the curvatures of the microlenses 121 located on different concentric circles 122 are different. Because the center distances from the different microlenses 121 on the same concentric circle 122 to the first surface 111 are the same, and the deflection degrees of the light rays at the corresponding positions when passing through the optical element 100 are the same, the microlenses 121 with the same curvature can have the same light receiving effect on the light rays, so that the light rays passing through the optical element 100 are more uniform. The distances between the microlenses 121 on different concentric circles 122 and the center of the first surface 111 are different, and the deflection degrees of the light rays at the corresponding positions when passing through the optical element 100 are also different, so that the microlenses 121 with different curvatures respectively have different light receiving effects on the light rays, so that the different positions on the optical element 100 can have better imaging effects.

Meanwhile, in order to cooperate with the microlens structure 120 for better imaging, referring to fig. 3, the fresnel lens 130 includes a central lens 131 located at the central position of the second surface 112, and a plurality of annular lenses 132 arranged in an annular array around the central lens 131. Similar to the first surface 111, the center of the second surface 112 is the centroid, in this embodiment, the lens substrate 110 is a cylinder structure, and the second surface 112 is a circle, and the center of the second surface 112 is the center of the circle. By arranging the fresnel lens 130 to include the central lens 131 at the central position of the second surface 112 and the plurality of annular lenses 132 arranged in an annular array around the central lens 131, that is, removing as much optical material as possible from the second surface 112 of the lens base layer 110, only the curvature of the lens base layer 110 is preserved, and the fresnel lens 130 is made lighter and thinner without affecting the imaging effect thereof, thereby further reducing the thickness of the optical element 100.

On this basis, in order to improve the integrity of the optical element 100, as shown in fig. 1, the annular lenses 132 are disposed in one-to-one correspondence with the concentric circles 122. The plurality of annular lenses 132 arranged in the fresnel lens 130 in an annular array around the central lens 131 are arranged in one-to-one correspondence with the plurality of concentric circles 122 formed by the connecting lines of the centers of the microlenses 121 in the microlens structure 120, so that, in the use process of the optical element 100, light passing through each annular lens 132 of the fresnel lens 130 can enter the microlens 121 on the corresponding concentric circle 122 in the microlens structure 120 and is received by the microlens 121, and the imaging uniformity of the optical element 100 is improved on the premise of improving the imaging effect of the optical element 100.

Further, along the direction perpendicular to the second surface 112, the projection of the microlens 121 on the second surface 112 completely falls into the corresponding annular lens 132, that is, the orthographic projection of the microlens 121 on the second surface 112 completely falls into the corresponding annular lens 132, which means that the plurality of annular lenses 132 arranged around the central lens 131 in the fresnel lens 130 in an annular array can completely cover the microlenses 121 at the corresponding positions in the microlens structure 120, so that each microlens 121 can accurately collect light passing through different positions of the fresnel lens 130, and the situation that the light passing through different deflection degrees enters the same microlens 121 to cause imaging errors does not occur, thereby ensuring the imaging stability of the optical element 100.

Fig. 4 is a schematic full-sectional structural diagram of the camera module 10 according to an embodiment of the present application.

Referring to fig. 4, an embodiment of the present invention further provides a camera module 10, where the camera module 10 includes the optical element 100 and the photosensitive element 200, and the photosensitive element 200 is disposed opposite to the optical element 100. The photosensitive element 200 receives the light transmitted from the optical element 100, and after processing, the imaging function of the camera module 10 is realized. The camera module 10 of the embodiment of the present application can make the camera module 10 have a good imaging effect even under a large-angle scene on the premise of keeping a small thickness by adopting the optical element 100 as described above, and the imaging definition is high.

In the use process of the camera module 10, as shown in fig. 4, the first surface of the lens base layer 110 may face the photosensitive element 200, and since the microlens structure 120 is disposed on the first surface and the fresnel lens 130 is disposed on the second surface, when the light emitted by the light source 300 or the light reflected by the object 300 is irradiated onto the optical element 100, the light passes through each annular lens of the fresnel lens 130, enters the corresponding microlens on the concentric circle in the microlens structure 120, and is received by the microlens, therefore, the first surface of the lens base layer 110 faces the photosensitive element 200, that is, the first surface is used as the light exit surface of the optical element 100 and the second surface is used as the light entrance surface of the optical element 100 in the camera module 10, so that the optical element 100 can have a better imaging effect even in a large-angle scene, and the imaging definition is high.

The embodiment of the present application further provides an electronic device, which includes the camera module 10 as described above. The electronic device is any device having an image acquisition function, and may be any one of wearable devices such as a mobile phone, a tablet computer, a notebook computer, a personal digital assistant, an intelligent bracelet, and an intelligent watch, for example, and the camera module 10 cooperates with the electronic device to acquire and reproduce an image of a target object. Because in the above-mentioned module 10 of making a video recording, set up the microlens structure 120 including a plurality of microlenses on the first surface of lens basic unit 110, the fresnel lens 130 on the second surface of cooperation lens basic unit 110 images, and in microlens structure 120, the curvature of the microlens that the centre spacing apart from the first surface is different, can all play fine receipts light effect to the light of optical element 100 different positions department, under the prerequisite that keeps less thickness, can make electronic equipment also have better formation of image effect under to the wide-angle scene, the definition of formation of image is high.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present application, and the description thereof is more specific and detailed, but not construed as limiting the claims. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the concept of the present application, which falls within the scope of protection of the present application. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims (10)

1. An optical element, comprising:

a lens base layer having a first surface and a second surface opposite to the first surface;

a microlens structure including a plurality of microlenses arranged in an array on the first surface, the microlenses differing in curvature in spacing from a center of the first surface; and

and the Fresnel lens is arranged on the second surface.

2. An optical element according to claim 1, wherein a curvature of the microlens at a central position distant from the first surface is larger than a curvature of the microlens at a central position close to the first surface.

3. An optical element as recited in claim 1, wherein a plurality of said microlenses are arranged in an annular array on said first surface such that lines joining the centers of said microlenses form a plurality of concentric circles centered about the center of said first surface.

4. The optical element according to claim 3, wherein the microlenses located on the same concentric circle have the same curvature, and the microlenses located on different concentric circles have different curvatures.

5. An optical element as recited in claim 3, wherein said Fresnel lens comprises a central lens located at a central location of said second surface and a plurality of annular lenses arranged in an annular array around said central lens.

6. An optical element according to claim 5, wherein the annular lenses are arranged in one-to-one correspondence with the concentric circles.

7. An optical element as recited in claim 6, wherein an orthographic projection of said microlenses at said second surface falls entirely within a corresponding said annular lens.

8. The utility model provides a module of making a video recording which characterized in that includes:

an optical element according to any one of claims 1 to 7; and

and the photosensitive element is arranged opposite to the optical element.

9. The camera module of claim 8, wherein the first surface of the lens substrate faces the photosensitive element.

10. An electronic device, comprising: a camera module according to claim 9.

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