WO2022032855A1

WO2022032855A1 - Mobile terminal having built-in anamorphic lens

Info

Publication number: WO2022032855A1
Application number: PCT/CN2020/120801
Authority: WO
Inventors: 李�杰; 吴伟
Original assignee: 广东思锐光学股份有限公司
Priority date: 2020-08-14
Filing date: 2020-10-14
Publication date: 2022-02-17

Abstract

Disclosed in the present application is a mobile terminal having a built-in anamorphic lens. The mobile terminal is provided with a widescreen anamorphic lens; the widescreen anamorphic lens comprises a cylindrical lens group and a spherical lens group, and the cylindrical lens group at least comprises a group of negative focal power cylindrical lenses and a group of positive focal power cylindrical lenses. The widescreen anamorphic lens is provided in the mobile terminal, and due to optical characteristics of the cylindrical lenses in the widescreen anamorphic lens, incident light entering a horizontal direction can be "compressed", and incident light entering in a vertical direction remains unchanged, so that the widescreen anamorphic lens can compress a picture of a wide screen into a standard picture area. After the compressed picture photographed by the widescreen anamorphic lens is subjected to morphing correction by means of an image correction module, a widescreen picture and a widescreen video can be obtained, thereby meeting requirements of users for widescreen photographing of a mobile terminal.

Description

A mobile terminal with built-in anamorphic lens

technical field

The present application relates to the technical field of mobile phone lenses, and in particular, to a mobile terminal with a built-in anamorphic lens.

Background technique

The number of built-in cameras in mobile phones is increasing, and mainstream flagship mobile phones on the market have built-in wide-angle cameras, ultra-wide-angle cameras, telephoto cameras, and macro cameras. With the development of technology and demand in the future, there is bound to be a great demand for simple and fast shooting of wide-screen pictures and videos using mobile phones, which cannot be achieved by current mobile phone software and hardware.

SUMMARY OF THE INVENTION

Therefore, the technical problem to be solved by the present application is to overcome the defect that the built-in lens on the mobile phone in the prior art cannot realize the wide-screen shooting function, thereby providing a mobile terminal with a built-in anamorphic lens.

In order to solve the above-mentioned technical problems, the technical scheme of the present application is as follows:

A mobile terminal with a built-in anamorphic lens, the mobile terminal is provided with a wide-screen anamorphic lens; the wide-screen anamorphic lens includes a cylindrical lens group and a spherical lens group, and the cylindrical lens group at least includes one group A negative refractive power cylindrical lens and a group of positive refractive power cylindrical lenses.

Further, the cylindrical lens group and the spherical lens group are sequentially arranged along the optical axis from the object side to the image side.

Further, the cylindrical lens group includes a first lens, a second lens and a third lens arranged in sequence from the object side to the image side along the optical axis, and the first lens and the second lens have negative focal lengths A cylindrical lens, the third lens is a cylindrical lens with positive refractive power.

Further, the spherical lens group includes at least four aspherical lenses.

Further, the spherical lens group includes a fourth lens, a fifth lens, a sixth lens and a seventh lens arranged in sequence from the object side to the image side along the optical axis; the fourth lens, the fifth lens, the sixth lens Both the lens and the seventh lens are even-order aspherical lenses.

Further, a refractive element is arranged between the cylindrical lens group and the spherical lens group, and the refractive element is located on the optical path of the incident light incident through the cylindrical lens group and refracts the incident light to the The spherical lens group.

Further, the mechanical center line of the cylindrical lens group and the mechanical center line of the spherical lens group are perpendicular to each other.

Further, the inflection element is a triangular prism, a plane mirror or a pentaprism.

Further, the deformation coefficient of the wide-screen anamorphic lens ranges from 1.33 to 2.0.

Further, the thickness of the wide-screen anamorphic lens is not more than 12mm.

Further, the wide-screen anamorphic lens is embedded in the mobile terminal.

Further, the mobile terminal is a mobile phone or a tablet computer.

The technical solution of the present application has the following advantages:

1. The mobile terminal with a built-in anamorphic lens provided by this application, by arranging a small wide-screen anamorphic lens on the mobile terminal, utilizes at least one group of negative refractive power cylindrical lenses and a The optical characteristics of the cylindrical lens group composed of cylindrical lenses with positive refractive power can "compress" the incident light entering the cylindrical lens group horizontally, while the incident light entering the cylindrical lens group in the vertical direction remains unchanged. The screen anamorphic lens can compress the wide-screen image into the standard screen area. After the compressed image captured by the wide-screen anamorphic lens is deformed and corrected by the image correction module, wide-screen pictures and videos can be obtained, satisfying the user’s needs. Demand for wide-screen shooting on mobile terminals.

2. The mobile terminal provided by this application with a built-in anamorphic lens, the wide-screen anamorphic lens utilizes the optical characteristics of the cylindrical lens group composed of three cylindrical lenses to "compress" the incident light entering horizontally, while the vertical direction The incoming incident light remains unchanged, and then comprehensively corrects the incident light through the rear spherical lens group, thereby increasing the field of view of the horizontal shooting of the lens, making the aspect ratio of the actual shooting picture larger, and realizing wide-screen photos and videos. function.

3. The mobile terminal with the built-in anamorphic lens provided by this application, a refractive element is arranged between the cylindrical lens group and the spherical lens group of the wide-screen anamorphic lens, and the refractive element can change the direction of the optical path, thereby making the cylindrical lens. The group and the spherical lens group can be arranged in a non-linear form, such as a periscope 'L' shape, which is beneficial for installing a wide-screen anamorphic lens on a mobile terminal.

Description of drawings

In order to more clearly illustrate the specific embodiments of the present application or the technical solutions in the prior art, the accompanying drawings that need to be used in the description of the specific embodiments or the prior art will be briefly introduced below. The drawings are some embodiments of the present application. For those of ordinary skill in the art, other drawings can also be obtained from these drawings without any creative effort.

1 is a schematic diagram of the back of a mobile phone in which a wide-screen anamorphic lens is embedded in the first embodiment of the application;

2 is a cross-sectional view of a side surface of a mobile phone in which a wide-screen anamorphic lens is embedded in the first embodiment of the application;

3 is a schematic structural diagram of a lens group in Embodiment 1 of the present application;

4 is an optical path diagram of a lens group in Embodiment 1 of the present application;

Fig. 5 is the optical distortion curve of the lens group in the first embodiment of the application, the abscissa is the distortion percentage, and the ordinate is the field of view angle;

6 is a MTF (Modulation Transfer Function) transfer function curve of the lens group in Embodiment 1 of the present application, wherein the abscissa represents the spatial frequency, and the ordinate represents the MTF value.

Reference numeral description: 100, mobile terminal; 200, wide-screen anamorphic lens; 210, cylindrical lens group; 220, spherical lens group;

P1, the first lens; P2, the second lens; P3, the third lens; PM, the refractive element; P4, the fourth lens; P5, the fifth lens; P6, the sixth lens; P7, the seventh lens;

1. The object side of the first lens; 2. The image side of the first lens; 3. The object side of the second lens; 4. The image side of the second lens; 5. The image side of the third lens; 6. Refractive element 7, the light exit surface of the refractive element; 8, the object side of the fourth lens; 9, the image side of the fourth lens; 10, the diaphragm; 11, the object side of the fifth lens; 12, the first The image side of the five lenses; 13, the object side of the sixth lens; 14, the image side of the sixth lens; 15, the object side of the seventh lens; 16, the image side of the seventh lens.

detailed description

The technical solutions of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present application, but not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.

In the description of this application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. The indicated orientation or positional relationship is based on the orientation or positional relationship shown in the accompanying drawings, which is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the indicated device or element must have a specific orientation or a specific orientation. construction and operation, and therefore should not be construed as limitations on this application. Furthermore, the terms "first", "second", and "third" are used for descriptive purposes only and should not be construed to indicate or imply relative importance.

In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense, for example, it may be a fixed connection or a detachable connection Connection, or integral connection; can be mechanical connection, can also be electrical connection; can be directly connected, can also be indirectly connected through an intermediate medium, can be internal communication between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood in specific situations.

In addition, the technical features involved in the different embodiments of the present application described below can be combined with each other as long as there is no conflict with each other.

Example 1

As shown in Figures 1 and 2, a mobile terminal with a built-in anamorphic lens is provided with a small wide-screen anamorphic lens 200 on the mobile terminal 100, and the wide-screen anamorphic lens 200 has the function of shooting squeezing anamorphic images. The wide-screen anamorphic lens 200 can be mounted on the mobile terminal by an embedded structure. For example, the mobile terminal 100 is provided with a groove, and the lens module containing the wide-screen anamorphic lens is integrally embedded and fixed on the groove. In other embodiments, the lens module containing the wide-screen anamorphic lens can also be rotated and connected to the mobile terminal through a rotating mechanism, and the rotating mechanism can specifically rotate a pin. In the above, during the rotation process of the lens module, at least one state is built into the mobile terminal. The built-in lens module can be understood as all or a part of the lens module extending into the interior of the mobile terminal, or it can be understood as the lens module is installed in the mobile terminal. After being installed on the mobile terminal, the lens module cannot be disassembled from the mobile terminal by other methods except the destructive disassembly method, so as to be different from the lens module installed by the plug-in structure.

In the widescreen anamorphic lens, the definition of widescreen means that the aspect ratio of the captured image is larger than the current HDTV screen aspect ratio of 16:9. For example, the aspect ratio of the captured image in the anamorphic lens is 2.7:1. This is a widescreen anamorphic lens. The distortion factor of a wide-screen anamorphic lens ranges from 1.33 to 2.0, for example, the distortion factor can be 1.33, 1.5, 1.8, 2.0, etc.

3 and 4, in this embodiment, the wide-screen anamorphic lens includes a cylindrical lens group 210, a spherical lens group 220, and a refractive element PM that are sequentially arranged from the object side to the image side. The cylindrical lens group 210 is at least It includes a group of negative refractive power cylindrical lenses and a group of positive refractive power cylindrical lenses. Using the optical characteristics of the cylindrical lens group consisting of at least one group of negative-power cylindrical lenses and one group of positive-power cylindrical lenses, the incident light entering the cylindrical lens group 210 horizontally can be "compressed", while the vertical The direction of the incident light entering the cylindrical lens group 210 remains unchanged, so the wide-screen anamorphic lens can compress the wide-screen image into a standard image area, and the compressed image captured by the wide-screen anamorphic lens passes through the image correction module. After the deformation is corrected, wide-screen pictures and videos can be restored to meet the needs of users for wide-screen photography of mobile terminals.

Wherein, the overall shape of the cylindrical lens is generally cylindrical or semi-cylindrical, which can be understood as a longitudinal section of a cylindrical glass body. The axis of the cylindrical lens is the axis of the cylindrical glass body, and the cylindrical lens includes a cylindrical surface and a plane; the cylindrical surface of the cylindrical lens is a parallel surface in the direction parallel to the axis, and a circular surface in the direction perpendicular to the axis. The direction parallel to the axis of the cylindrical lens is the axial meridian direction, and the direction perpendicular to the cylindrical lens and the axis is the direction of the refractive power meridian. The meridian and the refractive power meridian have different magnifications. According to this characteristic of the cylindrical lens, the incident light entering the cylindrical lens in the horizontal direction will be compressed, while the incident light entering the cylindrical lens in the vertical direction remains unchanged, so the wide The frame of the picture is compressed to a standard picture area and is taken in by the lens.

In this embodiment, the mobile terminal may be a mobile electronic terminal such as a mobile phone and a tablet computer.

In this embodiment, the optical structure schematic diagram and the optical path diagram of the wide-screen anamorphic lens are shown in FIG. 3 and FIG. 4 respectively. The wide-screen anamorphic lens includes a cylindrical lens group 210, The refractive element PM, the spherical lens group 220, the refractive element PM is located on the optical path of the incident light incident through the cylindrical lens group 210 and refracts the incident light to the spherical lens group 220, the mechanical centerline of the cylindrical lens group 210 and the spherical surface The mechanical centerlines of the lens groups 220 are perpendicular to each other. In other embodiments, the refractive element PM may also be located between a plurality of lens combinations in a cylindrical lens group or between a plurality of lens combinations in a spherical lens group.

In this embodiment, the cylindrical lens group is composed of three cylindrical lenses, the refractive element PM is any one of a plane mirror, a triangular prism or a pentaprism, and the spherical lens group is composed of four aspherical lenses. The wide-screen anamorphic lens arranged in this structure, in addition to the horizontal compression deformation effect of the picture, also has the visual effect of horizontal drawing and elliptical out-of-focus light spot. The light source will form a horizontally extending light, the thickness of this light is related to the shooting distance, the light intensity of the light source, and the deformation coefficient of the wide-screen anamorphic lens. Of course, it can be understood here that the number of cylindrical lenses constituting the cylindrical lens group may also be four or more, and the number of aspheric lenses constituting the spherical lens group may also be more than four, as long as the cylindrical lens group is constituted The cylindrical lens of the lens group can "compress" the incident light entering horizontally, while the incident light entering in the vertical direction remains unchanged. The increase of the field of view makes the aspect ratio of the actual shot larger, so that wide-screen video or photos can be obtained without sacrificing pixels.

In this embodiment, the cylindrical lens group includes a first lens P1, a second lens P2 and a third lens P3 which are arranged in sequence from the object side to the image side along the optical axis; the first lens P1 and the second lens P2 are negative The refractive power cylindrical lens, and the third lens P3 is a positive refractive power cylindrical lens. The spherical lens group includes a fourth lens P4, a fifth lens P5, a sixth lens P6 and a seventh lens P7 which are sequentially arranged along the optical axis from the object side to the image side; the fourth lens P4, the fifth lens P5 and the sixth lens Both P6 and the seventh lens P7 are even-order aspherical lenses. The aspheric coefficient of an aspheric lens satisfies the following equation:

Z=cy ² /[1+{1−(1+k)c ² y ² } ^+1/2 ]+A ₄ y ⁴ +A ₆ y ⁶ +A ₈ y ⁸ +A ₁₀ y ¹⁰

Among them: Z is the sag of aspheric surface, c is the paraxial curvature of the aspheric surface, y is the lens diameter, k is the conic coefficient, A4 is the _4th -order aspherical coefficient, A6 is the _6th -order aspherical coefficient, and A8 is the _8th -order aspherical coefficient The spherical coefficient, A ₁₀ , is a tenth-order aspheric coefficient.

In this embodiment, the object side and the near-optical axis of the image side of the first lens P1 are both concave surfaces, the object side of the second lens P2 is convex at the near-optical axis, and the image-side near-optical axis of the second lens P2 is Concave surface, the image side of the third lens P3 is convex at the near optical axis, the angle between the light incident surface of the refractive element PM and the mechanical center line of the third lens P3 is 45 degrees, and the image side and object side of the fourth lens P4 are at The near optical axis is convex, which is a biconvex lens, the object side of the fifth lens P5 is concave at the near optical axis, and the image side and the object side of the sixth lens P6 are convex at the near optical axis, which is a double lens. Convex lens; the object side surface of the seventh lens P7 is convex at the near optical axis, the image side surface of the seventh lens P7 is concave at the near optical axis, and both the object side surface and the image side surface of the seventh lens P7 have inflection points off-axis .

A widescreen anamorphic lens is no thicker than 12mm. In this embodiment, the thickness of the cylindrical lens group along the optical axis is 5.50 mm; the thickness of the spherical lens group along the optical axis direction is 5.20 mm; the thickness of the refractive element PM along the optical axis direction is 2.40 mm. The overall size of this wide-screen anamorphic lens is small, and the mechanical center line of the cylindrical lens group is perpendicular to the mechanical center line of the spherical lens group, which can realize the embedded type of wide-screen anamorphic lens on thin mobile terminals. Install. Of course, the sizes of the cylindrical lens group, the spherical lens group and the refractive element PM can also be reduced in appropriate proportions.

The parameters of each lens in this embodiment are listed below:

Cylindrical aspheric coefficients:

1. K=-1.1411, A4=9.0e ^-4 , A6=6.37e- ⁵ , A8=2.5772e- ⁶ , A10=-7.20396e ^-7 ;

2. K=-1.6136, A4=1.9e ^-3 , A6=2.00e ^-4 , A8=5.01650e- ⁵ , A10=-6.30190e- ⁶ ;

5. K=-3.8613, A4=-3.0e ^-4 , A6=-1.00e ^-4 , A8=5.6852e- ⁶ ;

Aspheric coefficients:

8. K=-0.3923, A4=8.2e ^-3 , A6=4.00e ^-4 , A8=9.000e ^-4 , A10=-5.400e ^-3 ;

9. K=4.9815, A4=1.87e ^-2 , A6=-5.1e ^-3 , A8=-1.07e ^-2 , A10=3.60e ^-3 ;

11. K=-4.9919, A4=-3.18e ^-2 , A6=5.8e ^-3 , A8=-1.42e ^-2 , A10=1.27e ^-2 ;

12. K=-2.511, A4=4.8448e- ⁵ , A6=1.99e ^-2 , A8=-5.5e ^-3 , A10=7.5e ^-3 ;

13. K=0.8828, A4=-9.1e ^-3 , A6=7.0e ^-4 , A8=-7.0e ^-4 , A10=4.0e ^-4 ;

14. K=1.3393, A4=-4.1e ^-2 , A6=2.69e ^-2 , A8=-1.45e ^-2 , A10=2.8e ^-3 ;

15. K=4.9988, A4=-3.671e ^-1 , A6=1.166e ^-1 , A8=-1.60e ^-2 , A10=-4.90e ^-3 ;

16. K=-4.8512, A4=-1.256e ^-1 , A6=5.34e ^-2 , A8=-1.22e ^-2 , A10=7.0e ^-4 ;

Here, k is a conic coefficient, A4 is a 4th-order aspherical coefficient, A6 is a 6th-order aspherical coefficient, A8 is an 8th-order aspherical coefficient, and A10 is a 10th-order aspherical coefficient.

Fig. 5 is the optical distortion curve diagram of the lens group in the first embodiment, "img Ht" in Fig. 3 is the image height, and the full English name is image height; Fig. 6 is the MTF (Modulation Transfer Function) transfer function of the lens group in the first embodiment The curve graph (optical transfer function) can comprehensively reflect the imaging quality of the system. The smoother the curve shape and the higher the height relative to the X-axis, the better the imaging quality of the system and the higher the sharpness of the lens.

Embodiment 2

The difference from the first embodiment is that the positions of the cylindrical lens group and the spherical lens group are interchanged, the spherical lens group composed of four aspherical lenses is used as the front lens group, and the cylindrical lens composed of three cylindrical lenses is used as the front lens group. Compared with the wide-screen anamorphic lens in the structural arrangement of the first embodiment, the wide-screen anamorphic lens still has the function of image squeezing and distortion shooting, but the captured image The picture lacks the visual effects of horizontal brushing and elliptical out-of-focus spots.

Embodiment 3

The difference from the first embodiment is that the wide-screen anamorphic lens includes two groups of cylindrical lens groups and one group of spherical lens groups. The first cylindrical lens group, the spherical lens group, and the second cylindrical lens group follow the optical axis from the object Set in turn from square to image square. The wide-screen anamorphic lens in this arrangement not only has the effect of horizontal compression and deformation of the picture, but also has the visual effect of horizontal drawing and elliptical out-of-focus light spot, and the optical effect is the same as that of the first embodiment.

Obviously, the above-mentioned embodiments are only examples for clear description, and are not intended to limit the implementation manner. For those of ordinary skill in the art, changes or modifications in other different forms can also be made on the basis of the above description. There is no need and cannot be exhaustive of all implementations here. And the obvious changes or changes derived from this are still within the protection scope of the present invention.

Claims

A mobile terminal with a built-in anamorphic lens, characterized in that the mobile terminal is provided with a wide-screen anamorphic lens; the wide-screen anamorphic lens comprises a cylindrical lens group and a spherical lens group, and the cylindrical lens group At least one group of cylindrical lenses with negative refractive power and one group of cylindrical lenses with positive refractive power are included.
The mobile terminal with a built-in anamorphic lens according to claim 1, wherein the cylindrical lens group and the spherical lens group are sequentially arranged along the optical axis from the object side to the image side.
The mobile terminal with a built-in anamorphic lens according to claim 1 or 2, wherein the cylindrical lens group comprises a first lens, a second lens, and a first lens, a second lens, and a first lens, which are sequentially arranged along the optical axis from the object side to the image side. Three lenses, the first lens and the second lens are cylindrical lenses with negative refractive power, and the third lens is a cylindrical lens with positive refractive power.
The mobile terminal with a built-in anamorphic lens according to claim 1 or 2, wherein the spherical lens group includes at least four aspherical lenses.
The mobile terminal with a built-in anamorphic lens according to claim 4, wherein the spherical lens group comprises a fourth lens, a fifth lens, a sixth lens and The seventh lens; the fourth lens, the fifth lens, the sixth lens and the seventh lens are all even-order aspherical lenses.
The mobile terminal with a built-in anamorphic lens according to claim 2, wherein a refractive element is arranged between the cylindrical lens group and the spherical lens group, and the refractive element is located through the cylindrical surface The incident light rays incident on the lens group are on the optical path and the incident light rays are refracted to the spherical lens group.
The mobile terminal with a built-in anamorphic lens according to claim 6, wherein the mechanical center line of the cylindrical lens group and the mechanical center line of the spherical lens group are perpendicular to each other.
The mobile terminal with a built-in anamorphic lens according to claim 6, wherein the inflection element is a triangular prism, a plane mirror or a pentaprism.
The mobile terminal with a built-in anamorphic lens according to claim 1, wherein the deformation coefficient of the wide-screen anamorphic lens ranges from 1.33 to 2.0.
The mobile terminal with a built-in anamorphic lens according to claim 1, wherein the thickness of the wide-screen anamorphic lens is not greater than 12 mm.
The mobile terminal with a built-in anamorphic lens according to claim 1, wherein the wide-screen anamorphic lens is embedded in the mobile terminal.
The mobile terminal with a built-in anamorphic lens according to claim 1, wherein the mobile terminal is a mobile phone or a tablet computer.