A mobile terminal with built-in anamorphic lens

Abstract

The present invention discloses a mobile terminal with a built-in anamorphic lens, wherein 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, wherein the cylindrical lens group comprises at least a group of negative optical power cylindrical lenses and a group of positive optical power cylindrical lenses. The wide-screen anamorphic lens is provided in the mobile terminal, and the optical characteristics of the cylindrical lens in the wide-screen anamorphic lens can "compress" the incident light entering horizontally, while the incident light entering vertically 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 can be distorted and corrected by an image correction module to obtain a wide-screen picture and video, thereby satisfying the user's demand for wide-screen shooting of the mobile terminal.

Description

Technical Field

[0001] The present invention relates to the technical field of mobile phone lenses, and in particular to a mobile terminal with a built-in anamorphic lens. Background Art

[0002] There are more and more built-in cameras in mobile phones. The mainstream flagship phones on the market already have built-in wide-angle cameras, ultra-wide-angle cameras, telephoto cameras, and macro cameras. With the development of future technology and demand, it is bound to be a major demand for using mobile phones to simply and quickly shoot wide-screen pictures and videos, which is currently impossible for mobile phone software and hardware to achieve. Summary of the invention

[0003] Therefore, the technical problem to be solved by the present invention 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.

[0004] In order to solve the above technical problems, the technical solution of the present invention is as follows:

[0005] A mobile terminal with a built-in anamorphic lens is provided on the mobile terminal. The wide-screen anamorphic lens comprises a cylindrical lens group and a spherical lens group. The cylindrical lens group comprises at least one group of negative optical power cylindrical lenses and one group of positive optical power cylindrical lenses.

[0006] Furthermore, the cylindrical lens group and the spherical lens group are arranged in sequence from the object side to the image side along the optical axis.

[0007] Furthermore, 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, the first lens and the second lens are negative optical power cylindrical lenses, and the third lens is a positive optical power cylindrical lens.

[0008] Furthermore, the spherical lens group includes at least four aspherical lenses.

[0009] Furthermore, 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 and the seventh lens are all even-order aspherical lenses.

[0010] Furthermore, a refracting element is provided between the cylindrical lens group and the spherical lens group. The refracting element is located on the optical path of the incident light incident through the cylindrical lens group and refracts the incident light to the spherical lens group.

[0011] Furthermore, the mechanical center line of the cylindrical lens group and the mechanical center line of the spherical lens group are perpendicular to each other.

[0012] Furthermore, the refracting element is a prism, a plane mirror or a pentaprism.

[0013] Furthermore, the distortion coefficient of the widescreen anamorphic lens ranges from 1.33 to 2.0.

[0014] Furthermore, the thickness of the widescreen anamorphic lens is no more than 12 mm.

[0015] Furthermore, the wide-screen anamorphic lens is embedded in the mobile terminal.

[0016] Furthermore, the mobile terminal is a mobile phone or a tablet computer.

[0017] The technical solution of the present invention has the following advantages:

[0018] 1. The mobile terminal with a built-in anamorphic lens provided by the present invention has a small wide-screen anamorphic lens arranged on the mobile terminal. By utilizing the optical properties of a cylindrical lens group consisting of at least one group of negative optical power cylindrical lenses and one group of positive optical power cylindrical lenses in the wide-screen anamorphic lens, the incident light entering the cylindrical lens group horizontally can be "compressed", while the incident light entering the cylindrical lens group vertically remains unchanged. Therefore, the wide-screen anamorphic lens can compress the wide-screen image into a standard image area. After the compressed image captured by the wide-screen anamorphic lens is distorted and corrected by an image correction module, a wide-screen picture and video can be obtained, thereby meeting the user's demand for wide-screen shooting of the mobile terminal.

[0019] 2. The mobile terminal with a built-in anamorphic lens provided by the present invention, the wide-screen anamorphic lens utilizes the optical properties of a cylindrical lens group composed of three cylindrical lenses to "compress" the incident light entering horizontally, while the incident light entering vertically remains unchanged, and then passes through the spherical lens group at the back to perform comprehensive correction on the incident light, thereby increasing the field of view of the lens for horizontal shooting, making the aspect ratio of the actual shot picture larger, and realizing the function of wide-screen photos and videos.

[0020] 3. In the mobile terminal with a built-in anamorphic lens provided by the present invention, a refractive element is arranged between the cylindrical lens group and the spherical lens group of the wide-screen anamorphic lens. The refractive element can change the direction of the light path, so that the cylindrical lens group and the spherical lens group can be arranged in a non-linear manner, such as a periscope 'L' shape, which is conducive to installing the wide-screen anamorphic lens on the mobile terminal. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0022] Figure 1 It is a schematic diagram of the back side of a mobile phone with a wide-screen anamorphic lens installed in an embedded manner in the first embodiment of the present invention;

[0023] Figure 2 It is a cross-sectional view of the side of a mobile phone with a wide-screen anamorphic lens installed in an embedded manner in the first embodiment of the present invention;

[0024] Figure 3 is a schematic structural diagram of a lens assembly in Embodiment 1 of the present invention;

[0025] Figure 4 is a light path diagram of the lens group in the first embodiment of the present invention;

[0026] Figure 5 is an optical distortion curve of the lens assembly in the first embodiment of the present invention, wherein the abscissa is the distortion percentage and the ordinate is the field of view angle;

[0027] Figure 6 : is the MTF (Modulation Transfer Function) transfer function curve of the lens group in the first embodiment of the present invention, wherein the abscissa represents the spatial frequency and the ordinate represents the MTF value.

[0028] Description of reference numerals: 100, mobile terminal; 200, wide-screen anamorphic lens; 210, cylindrical lens group; 220, spherical lens group;

[0029] P1, first lens; P2, second lens; P3, third lens; PM, refractive element; P4, fourth lens; P5, fifth lens; P6, sixth lens; P7, seventh lens;

[0030] 1. Object-side surface of the first lens; 2. Image-side surface of the first lens; 3. Object-side surface of the second lens; 4. Image-side surface of the second lens; 5. Image-side surface of the third lens; 6. Light incident surface of the refractive element; 7. Light exit surface of the refractive element; 8. Object-side surface of the fourth lens; 9. Image-side surface of the fourth lens; 10. Stop; 11. Object-side surface of the fifth lens; 12. Image-side surface of the fifth lens; 13. Object-side surface of the sixth lens; 14. Image-side surface of the sixth lens; 15. Object-side surface of the seventh lens; 16. Image-side surface of the seventh lens. DETAILED DESCRIPTION

[0031] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0032] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0033] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0034] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0035] Embodiment 1

[0036] like Figure 1 and Figure 2As shown, a mobile terminal with a built-in anamorphic lens is provided on the mobile terminal 100, and a small wide-screen anamorphic lens 200 is provided. The wide-screen anamorphic lens 200 has the function of shooting squeezed anamorphic images. The wide-screen anamorphic lens 200 can be installed on the mobile terminal in an embedded structure. For example, a groove is provided on the mobile terminal 100, and the lens module containing the wide-screen anamorphic lens is embedded and fixed in the groove as a whole. In other embodiments, the lens module containing the wide-screen anamorphic lens can also be rotatably connected to the mobile terminal through a rotating mechanism. The rotating mechanism can specifically be a rotating pin. The lens module containing the wide-screen anamorphic lens is rotatably connected to the rotating pin. During the rotation process, the lens module has at least one state of being built-in on the mobile terminal. The built-in of the lens module can be understood as all or part of the lens module extending into the interior of the mobile terminal, or it can be understood as that after the lens module is installed on the mobile terminal, the lens module cannot be removed from the mobile terminal in any other manner except the destructive removal manner, so as to distinguish it from the lens module installed in an external structure.

[0037] In widescreen anamorphic lenses, the definition of widescreen refers to the aspect ratio of the image being shot is greater than the current high-definition television screen aspect ratio of 16:9. For example, the aspect ratio of the image shot in an anamorphic lens is 2.7:1, which is a widescreen anamorphic lens. The distortion coefficient of a widescreen anamorphic lens ranges from 1.33 to 2.0, for example, the distortion coefficient can be 1.33, 1.5, 1.8, 2.0, etc.

[0038] Combination Figure 3 and Figure 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 arranged in sequence from the object side to the image side, and the cylindrical lens group 210 includes at least one group of negative power cylindrical lenses and one group of positive power cylindrical lenses. By utilizing the optical properties of the cylindrical lens group composed 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 incident light entering the cylindrical lens group 210 vertically remains unchanged, so the wide-screen anamorphic lens can compress the wide-screen image into the standard image area, and the compressed image captured by the wide-screen anamorphic lens can be restored to obtain wide-screen pictures and videos after being distorted and corrected by the image correction module, thereby meeting the user's demand for wide-screen shooting of mobile terminals.

[0039] Among them, the overall shape of the cylindrical lens is generally cylindrical or semi-cylindrical, which can be understood as a part of the cylindrical glass body cut longitudinally. 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 of the cylindrical lens parallel to the axis is the axial meridian direction, and the direction of the cylindrical lens perpendicular to the axis is the refractive power meridian direction. The radii of the cylindrical lens in the axial meridian direction and the refractive power meridian are different, so the cylindrical lens has different magnifications on the axial meridian and the refractive power meridian. According to this characteristic of the cylindrical lens, the incident light entering the cylindrical lens horizontally will be compressed, while the incident light entering the cylindrical lens vertically will remain unchanged, so the wide picture can be compressed to the standard picture area to be captured by the lens.

[0040] In this embodiment, the mobile terminal may be a mobile electronic terminal such as a mobile phone or a tablet computer.

[0041] In this embodiment, the optical structure principle diagram and the optical path diagram of the wide-screen anamorphic lens are respectively as follows: Figure 3 and Figure 4 As shown, the widescreen anamorphic lens includes a cylindrical lens group 210, a refracting element PM, and a spherical lens group 220, which are arranged in sequence from the object side to the image side. The refracting 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 center line of the cylindrical lens group 210 and the mechanical center line of the spherical lens group 220 are perpendicular to each other. In other embodiments, the refracting element PM can also be located between multiple lens combinations in the cylindrical lens group or between multiple lens combinations in the spherical lens group.

[0042] 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 prism or a pentaprism, and the spherical lens group is composed of four aspherical lenses. The widescreen anamorphic lens arranged in this structural form, in addition to the horizontal compression deformation effect of the picture, also has the visual effects of horizontal brushing and elliptical out-of-focus light spots. Horizontal brushing refers to the formation of a horizontally extending light on the light source of the picture, and the thickness of this light is related to the shooting distance, the light intensity of the light source, and the deformation coefficient of the widescreen anamorphic lens. Of course, it can be understood here that the number of cylindrical lenses constituting the cylindrical lens group can also be four or more, and the number of aspherical lenses constituting the spherical lens group can also be four or more, as long as the cylindrical lenses constituting the cylindrical lens group can "compress" the incident light entering horizontally, while the incident light entering vertically remains unchanged, the spherical lenses constituting the spherical lens group can perform comprehensive correction on the incident light, thereby increasing the field of view of the lens for horizontal shooting, increasing the aspect ratio of the actual shot, and obtaining wide-screen video or photos without sacrificing pixels.

[0043] In this embodiment, the cylindrical lens group includes a first lens P1, a second lens P2, and a third lens P3 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 power cylindrical lenses, and the third lens P3 is a positive 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 arranged in sequence from the object side to the image side along the optical axis; the fourth lens P4, the fifth lens P5, the sixth lens P6, and the seventh lens P7 are all even-order aspherical lenses. The aspherical coefficients of the aspherical lenses satisfy the following equation:

[0044] Z=cy 2 / [1+{1-(1+k)c 2 y 2} +1 / 2 ]+A4y 4 +A6y 6 +A8y 8 +A 10 y 10

[0045] Where: Z is the aspheric surface sag, c is the aspheric surface paraxial curvature, y is the lens aperture, k is the cone coefficient, A4 is the 4th aspheric surface coefficient, A6 is the 6th aspheric surface coefficient, A8 is the 8th aspheric surface coefficient, A 10 is the 10th-order aspheric coefficient.

[0046] In this embodiment, the object side surface and the image side surface of the first lens P1 are both concave at the near optical axis, the object side surface of the second lens P2 is convex at the near optical axis, the image side surface of the second lens P2 is concave at the near optical axis, the image side surface 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, the image side surface and the object side surface of the fourth lens P4 are both convex at the near optical axis, and are biconvex lenses, the object side surface of the fifth lens P5 is concave at the near optical axis, the image side surface and the object side surface of the sixth lens P6 are both convex at the near optical axis, and are biconvex lenses; 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 its object side surface and image side surface both have inflection points at off-axis positions.

[0047] The thickness of the widescreen anamorphic lens is not more than 12mm. In this embodiment, the thickness of the cylindrical lens group along the optical axis is 5.50mm; the thickness of the spherical lens group along the optical axis is 5.20mm; and the thickness of the refractive element PM along the optical axis is 2.40mm. The overall size of this widescreen anamorphic lens is relatively small, and the mechanical center line of the cylindrical lens group is perpendicular to the mechanical center line of the spherical lens group, so that the widescreen anamorphic lens can be embedded in a thinner mobile terminal. Of course, the sizes of the cylindrical lens group, the spherical lens group and the refractive element PM can also be appropriately reduced in proportion.

[0048] The parameters of each lens in this embodiment are listed below:

[0049]

[0050] Cylindrical aspheric coefficient:

[0051] 1. K = -1.1411, A4 = 9.0e －4 , A6=6.37e －5 , A8=2.5772e －6 , A10 = -7.20396e －7 ;

[0052] 2. K = -1.6136, A4 = 1.9e －3 , A6=2.00e －4 , A8=5.01650e －5 , A10 = -6.30190e －6 ;

[0053] 5. K=-3.8613, A4=-3.0e －4 , A6=-1.00e －4 , A8=5.6852e －6 ;

[0054] Aspheric coefficients:

[0055] 8、K=-0.3923,A4=8.2e －3 ,A6=4.00e －4 ,A8=9.000e －4 ,A10=-5.400e －3 ;

[0056] 9、K=4.9815,A4=1.87e －2 ,A6=-5.1e －3 ,A8=-1.07e －2 ,A10=3.60e －3 ;

[0057] 11、K=-4.9919,A4=-3.18e －2 ,A6=5.8e －3 ,A8=-1.42e －2 ,A10=1.27e －2 ;

[0058] 12、K=-2.511,A4=4.8448e －5 ,A6=1.99e －2 ,A8=-5.5e －3 ,A10=7.5e －3 ;

[0059] 13、K=0.8828,A4=-9.1e －3 ,A6=7.0e －4 ,A8=-7.0e －4 ,A10=4.0e －4 ;

[0060] 14、K=1.3393,A4=-4.1e －2 ,A6=2.69e －2 ,A8=-1.45e －2 ,A10=2.8e －3 ;

[0061] 15、K=4.9988,A4=-3.671e －1 ,A6=1.166e －1 ,A8=-1.60e －2 ,A10=-4.90e －3 ;

[0062] 16、K=-4.8512,A4=-1.256e －1 ,A6=5.34e －2 ,A8=-1.22e －2, A10=7.0e －4 ;

[0063] Among them, k is the cone coefficient, A4 is the 4th-order aspheric coefficient, A6 is the 6th-order aspheric coefficient, A8 is the 8th-order aspheric coefficient, and A10 is the 10th-order aspheric coefficient.

[0064] Figure 5 is an optical distortion curve diagram of the lens group in Example 1, Figure 3 "img Ht" in Chinese is image height, and its full English name is image height; Figure 6 The MTF (Modulation Transfer Function) transfer function curve (optical transfer function) of the lens group in Example 1 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 clarity of the lens.

[0065] Embodiment 2

[0066] 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 serves as the front lens group, and the cylindrical lens group composed of three cylindrical lenses serves as the rear lens group; compared with the wide-screen anamorphic lens of the first embodiment, the wide-screen anamorphic lens of this structural arrangement still has the function of image squeezing and anamorphic shooting, but the captured image lacks the visual effects of horizontal brushing and elliptical out-of-focus light spots.

[0067] Embodiment 3

[0068] The difference from the first embodiment is that the wide-screen anamorphic lens includes two cylindrical lens groups and one spherical lens group, and the cylindrical lens group 1, the spherical lens group, and the cylindrical lens group 2 are arranged in sequence from the object side to the image side along the optical axis. The wide-screen anamorphic lens with this arrangement not only has the effect of horizontal compression deformation of the picture, but also has the visual effects of horizontal drawing and elliptical out-of-focus light spots, and the optical effect is the same as that of the first embodiment.

[0069] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.

Claims

1. 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 comprises at least one group of negative optical power cylindrical lenses and one group of positive optical power cylindrical lenses; The cylindrical lens group and the spherical lens group are arranged in sequence from the object side to the image side along the optical axis; A refracting element is provided between the cylindrical lens group and the spherical lens group. The refracting element is located on the optical path of the incident light incident through the cylindrical lens group and refracts the incident light to the spherical lens group.

2. The mobile terminal with a built-in anamorphic lens according to claim 1, characterized in that: 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, the first lens and the second lens are negative optical power cylindrical lenses, and the third lens is a positive optical power cylindrical lens.

3. The mobile terminal with a built-in anamorphic lens according to claim 1, characterized in that: The spherical lens group includes at least four aspherical lenses.

4. The mobile terminal with a built-in anamorphic lens according to claim 3, characterized in that: The spherical lens group includes a fourth lens, a fifth lens, a sixth lens and a seventh lens which are sequentially arranged along the optical axis from the object side to the image side; the fourth lens, the fifth lens, the sixth lens and the seventh lens are all even-order aspherical lenses.

5. The mobile terminal with a built-in anamorphic lens according to claim 1, characterized in that: The mechanical center line of the cylindrical lens group and the mechanical center line of the spherical lens group are perpendicular to each other.

6. The mobile terminal with a built-in anamorphic lens according to claim 1, characterized in that: The refracting element is a prism, a plane mirror or a pentaprism.

7. The mobile terminal with a built-in anamorphic lens according to claim 1, characterized in that: The distortion coefficient of the widescreen anamorphic lens ranges from 1.33 to 2.

0.

8. The mobile terminal with a built-in anamorphic lens according to claim 1, characterized in that: The thickness of the widescreen anamorphic lens is no more than 12 mm.

9. The mobile terminal with a built-in anamorphic lens according to claim 1, characterized in that: The wide-screen anamorphic lens is embedded in the mobile terminal.

10. The mobile terminal with a built-in anamorphic lens according to claim 1, characterized in that: The mobile terminal is a mobile phone or a tablet computer.

Images