CN111866328A

CN111866328A - Camera module and mobile terminal

Info

Publication number: CN111866328A
Application number: CN201910364078.4A
Authority: CN
Inventors: 江依达; 郭利德; 邓良君
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2019-04-30
Filing date: 2019-04-30
Publication date: 2020-10-30
Anticipated expiration: 2039-04-30
Also published as: CN111866328B

Abstract

The application provides a camera module and a mobile terminal, wherein the camera module comprises a bottom plate, a reflecting mirror, a first lens group and a second lens group, wherein the reflecting mirror is packaged on the bottom plate and used for refracting an optical axis; the anti-shake device also comprises an anti-shake motor for driving the reflecting mirror to rotate; the second lens group comprises a plurality of reflecting surfaces for folding ray paths, and at least part of the reflecting surfaces are reflecting surfaces through which the rays are transmitted when the rays are irradiated at a set angle. In the above technical scheme, through increasing the second mirror group in the camera module, this second mirror group is gone up and is had a plurality of plane of reflection and can the face of transmission to light is when passing the second mirror group, can fold the route of light, and then shortens the length of camera module.

Description

Camera module and mobile terminal

Technical Field

The application relates to the technical field of camera shooting, in particular to a camera module and a mobile terminal.

Background

With the popularization of consumer electronic mobile phones, a mobile phone camera has gradually replaced a digital camera, and with higher requirements on shooting, a telephoto lens is more and more important to be developed in the mobile phone camera, so that higher magnification is limited by the size of the mobile phone, and how to miniaturize the telephoto camera with higher magnification on the premise of meeting the performance is a key point. A folded lens camera module as used in the prior art changes the direction of light passing through a first optical axis onto a second optical axis by using the principle of light reflection and forms an image at an image sensor. However, the Total optical length is not fundamentally changed by using a single reflection element to fold the optical path, the Focal length range of the folded camera module is 8-14mm, the telescope ratio | TTL (Total track length)/f (Focal length) | is in the range of 0.8-1.2, the folded camera module is difficult to be applied to a long-focus lens with the Focal length larger than 14mm, and the module size is still long.

Disclosure of Invention

The application provides a camera module and mobile terminal for keep the miniaturization of camera module when increasing the focus, and then improve the effect of making a video recording.

In a first aspect, a camera module is provided, which includes a base plate, a reflecting mirror encapsulated on the base plate for deflecting an optical axis, and a first lens group and a second lens group, wherein the first lens group and the second lens group are arranged along the optical axis. Still including being used for driving speculum pivoted anti-shake motor can prevent through this motor that sets up that the shake from to shooing the influence that brings. When the second lens group is specifically arranged, the second lens group includes a plurality of reflective surfaces for folding the light path, and at least a part of the reflective surfaces are reflective surfaces through which the light is transmitted when the light is irradiated at a set angle. In the above technical scheme, through increasing the second mirror group in the camera module, this second mirror group is gone up and is had a plurality of plane of reflection and can the face of transmission to light is when passing the second mirror group, can fold the route of light, and then shortens the length of camera module, realizes the miniaturization.

When the reflecting surface of the second lens group is arranged, the reflecting surface comprises a first reflecting surface and a second reflecting surface, and the second reflecting surface is a reflecting surface which is permeable to the light rays when the light rays are irradiated at a set angle; wherein the number of the second reflecting surfaces is at least three. The propagation path of light in the second lens group is folded by the matching of the arranged second reflecting surface and the first reflecting surface.

When the second lens group is specifically arranged, the second lens group may adopt different structural forms, such as a single lens, or a plurality of lenses, and in a specific embodiment, the second lens group includes a first prism and a second prism which are oppositely arranged; the first prism is provided with a light incident surface, a second reflecting surface and at least one first reflecting surface; the second prism is provided with two opposite second reflecting surfaces and at least one first reflecting surface, wherein the second reflecting surface far away from the first prism is a light-emitting surface. The propagation path of the light in the second lens group is folded by adopting the cooperation of the two prisms.

When the first prism is specifically arranged, a second reflecting surface is arranged on the first prism and is adjacent to the light incident surface, wherein the included angle between the second reflecting surface of the first prism and the light incident surface is within the range of 19.5-25.5 degrees. In a specific embodiment, the angle between the second reflection surface of the first prism and the light incident surface is 22.5 °.

When the first prism is arranged specifically, a first reflecting surface is arranged on the first prism, and the first reflecting surface and the second reflecting surface are arranged on two sides of the light incident surface respectively; the included angle between the first reflecting surface of the first prism and the light incident surface is within the range of 109.5-115.5 degrees. In one specific embodiment, the first reflecting surface of the first prism forms an angle of 112.5 ° with the light incident surface.

When the second prism is specifically arranged, the light-emitting surface on the second prism is parallel to the light-in surface.

In addition, the second prism is provided with a first reflecting surface, and the included angle between the first reflecting surface of the second prism and the light-emitting surface is within the range of 64.5-70.5 degrees. As a specific implementation, the included angle between the first reflection surface of the second prism and the light exit surface is 67.5 °.

When the second prism is specifically arranged, the other second reflecting surface of the second prism is respectively adjacent to the first reflecting surface and the light-emitting surface; and the included angle between the other second reflecting surface of the second prism and the light-emitting surface is within the range of 42.5-48.5 degrees. As a specific implementation, an included angle between the other second reflection surface of the second prism and the light emitting surface is 45 °.

When specifically setting up the camera module, the telescope ratio of camera module: and | TTL/f | is less than or equal to 0.85. Wherein, the telescope ratio: refers to the ratio of the total optical length to the focal length. Wherein the optical total length is a total length from the object-side surface of the first lens element along the optical axis to the imaging surface.

When specifically setting up the camera module, the rear intercept of camera module and effective focal length's ratio: the | BFL/f | is less than or equal to 0.4. The rear intercept is the total length from the image side surface of the last lens element to the imaging surface along the optical axis.

When the first lens group is specifically arranged, the first lens group may adopt different structures, for example, the first lens group includes: a first lens having a positive refractive power and a second lens having a negative refractive power; the first lens and the second lens are arranged from the object side to the image side.

When the first lens and the second lens are specifically arranged, the refractive indexes Nd of the first lens and the second lens are more than or equal to 1.55, and the Abbe number Vd of the second lens is less than or equal to 32. Or the refractive index Nd of the first lens is more than or equal to 1.53, the refractive index Nd of the second lens is more than or equal to 1.62, and the Abbe number Vd of the second lens is less than or equal to 25.

In addition to the above structure, the first lens group may also adopt other structures, such as the first lens group including a first lens with positive focal power, a second lens with negative focal power, and a third lens with negative focal power; the first lens, the second lens and the third lens are arranged from the object side to the image side.

When the three lenses are specifically arranged, the refractive indexes Nd of the first lens and the second lens are more than or equal to 1.55, the Abbe number Vd of the second lens is less than or equal to 32, and the Abbe number Vd of the third lens is more than or equal to 50.

When the reflector is arranged, the reflector is a prism or a plane mirror; wherein the prism or the plane mirror is positioned in front of the first lens group; or the prism or the plane mirror is positioned between any two lenses of the first lens group.

In addition, the camera module further comprises a variable curved lens positioned on one side of the first lens group close to the object side. The anti-shake can be realized by the arranged variable curved lens.

When the variable curved lens is specifically arranged, the variable curved lens is a liquid lens. The anti-shake effect is realized by changing the shape of the liquid lens.

When the anti-shake motor is specifically arranged, the anti-shake motor is a shape memory alloy wire motor, an electromagnetic motor or a piezoelectric motor.

When the first lens group is arranged, the first lens group is a flat lens group.

In a second aspect, a mobile terminal is provided, which includes a housing and the camera module set in any one of the above-mentioned housings. In the above technical scheme, through increasing the second mirror group in the camera module, this second mirror group is gone up and is had a plurality of plane of reflection and can the face of transmission to light is when passing the second mirror group, can fold the route of light, and then shortens the length of camera module.

Drawings

Fig. 1 is a structural reference diagram of a camera module according to an embodiment of the present application;

FIG. 2 is a schematic view of angles of each surface of a second lens group according to an embodiment of the present application;

Fig. 3 is a reference diagram of another structure of a camera module according to an embodiment of the present disclosure;

fig. 4 is a reference diagram of another structure of a camera module according to an embodiment of the present disclosure;

fig. 5 is a reference diagram of another structure of a camera module according to an embodiment of the present disclosure;

fig. 6 is a reference diagram of another structure of a camera module according to an embodiment of the present disclosure;

fig. 7 is a reference diagram of another structure of a camera module according to an embodiment of the present disclosure;

fig. 8 is a schematic view illustrating a combination of an anti-shake motor and a reflector according to an embodiment of the present disclosure;

fig. 9 is a reference diagram of another structure of a camera module according to an embodiment of the present application.

Detailed Description

In order to make the objects, technical solutions and advantages of the present application more clear, the present application will be further described in detail with reference to the accompanying drawings.

For convenience in understanding the camera module provided in the embodiments of the present application, an application scenario of the camera module is first described, and the camera module is applied to a mobile terminal, such as a notebook computer, a tablet computer, or a mobile phone. When the mobile terminal camera module is used, the camera module is fixed in the mobile terminal and can be used for shooting or taking pictures, but due to the gradual thinning development of the mobile terminal, the size of the camera module is limited not to be too large easily, and the camera shooting effect of the camera is greatly influenced. Therefore, in the embodiments of the present application, a camera module is provided, and the structure of the camera module is described in detail below with reference to specific drawings.

The camera module that this application embodiment provided can adopt periscopic's camera module. As shown in fig. 1, fig. 1 shows a specific structure of a camera module provided by an embodiment of the present application, the camera module employs a periscopic camera module, and at this time, the camera module includes a bottom plate 50, a reflecting mirror 10 packaged on the bottom plate 50 and used for deflecting an optical axis, a first lens group 20 and a second lens group 30 arranged along the optical axis, and when the reflecting mirror 10 is disposed, the reflecting mirror 10 may be disposed in front of the first lens group 10, or disposed between lenses in the first lens group 20. As shown in fig. 1, the camera module has two optical axes, which are a first optical axis and a second optical axis respectively, when light enters the camera module, the light enters the camera module along the first optical axis and is reflected to the second optical axis by the reflector 10 of the camera module, and is irradiated to the lens in the camera module in the transmission process, and the light irradiates the photoreceptor 40 after passing through the lens, and an optical filter (not shown in the figure) can be further disposed between the lens and the photoreceptor. The first lens group 20 and the second lens group 30 provided in the embodiment of the present application are described below by taking a periscopic camera module as an example.

First, a first Lens group 20 and a second Lens group 30 provided in the present embodiment are described, wherein the first Lens group 20 is a Lens group, and the second Lens group 30 is a Lens group for folding light paths. When the first lens group 20 and the second lens group 30 are disposed, the first lens group 20 and the second lens group 30 are disposed along the optical axis and bear the first lens group 20 and the second lens group 30 through the bottom plate 50. In addition, when the first lens group 20 and the second lens group 30 are specifically arranged, the first lens group 20 and the second lens group 30 may include different numbers of lenses, for example, the first lens group 20 may include one lens, or may include two or more lenses, and the specific arrangement may be determined according to actual needs. When the first lens group 20 includes two or more lenses, the two or more lenses may be disposed along the first optical axis, or disposed along the second optical axis, or partially disposed along the first optical axis, and partially disposed along the second optical axis, and may be defined as required in specific settings. In addition, when the lenses in the first lens group 20 are specifically arranged, different lenses can be selected according to the needs. For the second lens group 30, when the second lens group 30 is disposed, the second lens group 30 includes a plurality of reflective surfaces for folding the light path. When light travels into second lens group 30, the plurality of reflective surfaces are arranged such that light is reflected by the plurality of reflective surfaces after entering second lens group L2 to fold the travel path of light, and when the plurality of reflective surfaces are arranged, at least some of the plurality of reflective surfaces are reflective surfaces through which light is transmitted when irradiated at a predetermined angle, so that light can exit second lens group 30. When the plurality of reflecting surfaces are specifically arranged, the reflecting surfaces can be realized by adopting different prisms.

For convenience of describing the reflective surfaces in the second lens group 30, the reflective surfaces are divided according to their functions and named as a first reflective surface and a second reflective surface respectively, wherein the first reflective surface is a reflective surface that performs total reflection and does not allow light to pass through, and the second reflective surface is a reflective surface that allows light to pass through when the light is irradiated at a predetermined angle. When the first reflecting surface and the second reflecting surface are provided, the first reflecting surface and the second reflecting surface may be provided as needed. In addition, in order to greatly reduce the back intercept, the back intercept is the total length from the image side surface of the last lens element along the optical axis to the imaging surface. The number of the second reflecting surfaces is at least three, for example, three, four or five second reflecting surfaces are adopted. In the specific arrangement of the first reflective surface and the second reflective surface, the first reflective surface and the second reflective surface are surfaces on a prism, so that the second lens group 30 provided in the embodiment of the present application includes at least one prism, for example, the first reflective surface and the second reflective surface are formed by one prism, or the first reflective surface and the second reflective surface are formed by two or more prisms.

Taking the example of the second lens group 30 having two prisms as an example, for convenience of description, the two prisms are named as a first prism 31 and a second prism 32 respectively, and the first prism 31 and the second prism 32 are disposed opposite to each other, wherein the refractive index Nd of the first prism 31 and the second prism 32 is greater than or equal to 1.8, such as 1.9, 2.0, 2.1, and the like. When the first prism 31 and the second prism 32 are specifically arranged, the first prism 31 and the second prism 32 have an air gap along the direction of the second optical axis, so that when light enters the second lens group 30, total reflection of the full-field light can occur at least twice through the first reflecting surface, the light path is folded, and the physical length of the camera module is further shortened.

Specifically, when the first prism 31 and the second prism 32 are disposed, as shown in fig. 2, the first prism 31 is provided with a light incident surface 311, the second prism 32 is provided with a light emergent surface 323, and the light emergent surface 323 and the light incident surface 311 are located on two surfaces of the first prism 31 and the second prism 32, which are relatively far away from each other. When light propagates to the second lens assembly 30, the light enters the second lens assembly 30 through the light entrance surface 311, and then exits through the light exit surface 323 after being reflected and transmitted by the first and second reflection surfaces in the second lens assembly 30. For the convenience of understanding the first prism 31 and the second prism 32 provided in the embodiments of the present application, the structure thereof will be described in detail with reference to fig. 1 and 2.

As shown in fig. 1 and 2, the first prism 31 and the second prism 32 are disposed opposite to each other with an air gap therebetween. The first prism 31 and the second prism 32 each include the first reflecting surface and the second reflecting surface, and the number of the first reflecting surface and the second reflecting surface may be set as needed. The second lens group 30 will be described below by taking the group of second lenses L2 shown in fig. 2 as an example. First, a structure of the first prism 31 is described, in which the first prism 31 includes an incident surface 311, a first reflecting surface 312 and a second reflecting surface 313, wherein the second reflecting surface 313 is adjacent to the incident surface 311, and the first reflecting surface 312 and the second reflecting surface 313 are respectively arranged at two sides of the incident surface 311. In addition, the first reflection surface 312, the second reflection surface 313 and the light incident surface 311 form different angles, for example, an included angle between the second reflection surface 313 and the light incident surface 311 is in a range of 19.5 ° to 25.5 °. Specifically, the angles may be different angles such as 20 °, 22.5 °, 24 °, 25.5 °, and the like. The included angle between the first reflection surface 312 and the light incident surface 311 of the first prism 31 is between 109.5 and 115.5 °. Specifically, the angles may be different angles such as 109.5 °, 110.5 °, 112.5 °, and 115.5 °. When light enters the first prism 31 from the light incident surface 311 of the first prism 31, the light first irradiates the second reflecting surface 313, the second reflecting surface 313 irradiates the first reflecting surface 312 after the light is totally reflected, and the light is totally reflected by the first reflecting surface 312, irradiates the second reflecting surface 313, passes through the second reflecting surface 313 and then exits.

The light transmitted by the second reflecting surface 313 is incident into the second prism 32, and the second prism 32 includes two second reflecting surfaces opposite to each other and a first reflecting surface 322, and a certain included angle is formed between the two second reflecting surfaces and the first reflecting surface. For example, the included angle between the first reflection surface 322 of the second prism 32 and the light emitting surface 323 is within the range of 64.5-70.5 °. Specifically, the angles may be different angles such as 64.5 °, 65.5 °, 67.5 °, 68.5 °, and 70.5 °. The included angle between the other second reflection surface 321 of the second prism 32 and the light emitting surface 323 is within the range of 42.5-48.5 °. Specifically, the angles may be different angles such as 42.5 °, 44.5 °, 45 °, 47.5 °, and 48.5 °. One of the two second reflection surfaces is the light emitting surface 323, and the other second reflection surface 321 is parallel to the second reflection surface 313 of the first prism 31 and serves as the incident surface of the second prism 32. And the other second reflection surface 321 of the second prism 32 is adjacent to the first reflection surface 322 and the light emitting surface 323 respectively. After the light is emitted from the second reflection surface of the first prism 31, the light enters the second prism 32 through the second reflection surface 321 of the second prism 32, then the light irradiates the second reflection surface as the light emitting surface 323 and totally reflects on the second reflection surface, the reflected light irradiates the first reflection surface 322, and is reflected by the first reflection surface 322 to be totally reflected on the second reflection surface 321 as the incident surface of the second prism 32, and then the light is emitted from the light emitting surface 323, and the propagation in the second mirror group 30 is completed. As can be seen from the above description, the light rays undergo five total reflections in the second lens group 30, so that the propagation path of the light rays is folded, and the physical length of the camera module is shortened. Like in the camera module that this application embodiment provided, the telescope ratio of camera module: and | TTL/f | is less than or equal to 0.85. Wherein, the telescope ratio: refers to the ratio of the total optical length to the focal length. Wherein the optical total length is a total length from the object-side surface of the first lens element along the optical axis to the imaging surface. And the ratio of the back intercept to the effective focal length of the camera module: the | BFL/f | is less than or equal to 0.4. The rear intercept is the total length from the image side surface of the last lens element to the imaging surface along the optical axis.

When the first lens group 20 is matched with the second lens group 30, the first lens group 20 can comprise a plurality of lenses, which will be described below by way of example.

Referring first to fig. 3, fig. 3 shows an XZ plan view on the second optical axis of a camera module designed to cover the visible spectrum of 470nm to 650 nm. The camera module comprises a reflector 10 for folding an optical axis, and is arranged in an object space of the mirror assembly to fold light from the first optical axis to the second optical axis.

Wherein the first lens group 20 includes a first lens L1 having positive power and a second lens L2 having negative power, and a stop is located in front of the first lens L1, wherein the first lens L1 having positive power and a convex object-side surface functions to collect light rays in the camera module; the second lens element L2 with negative focal power and concave image-side surface corrects chromatic aberration caused by different wavelengths of light in the camera module, the second lens element L2 has a meniscus-shaped structure curved to the image side to correct peripheral light aberration, and reasonable parameter configuration makes the effective focal length of the imaging lens assembly 31mm, and the chief ray angle incident on the light inlet plane of the second lens element 30 through the first lens element 20 is less than 8 °.

Referring collectively to tables 1A-1C, tables 1A-1C provide various optical and physical parameter values for the camera module shown in fig. 3 that provide sufficient telephoto focal length and a small chief ray angle.

When the second lens group 30 is specifically disposed, it includes the first prism 31 and the second prism 32, and when the first prism 31 and the second prism 32 are specifically disposed, the included angle between the first reflection surface and the second reflection surface on the first prism 31 and the second prism 32 can refer to the above detailed description, and will not be described herein again. The light rays transmitted by the first lens group 20 are incident into the second lens group 30, and the light rays are reflected by the second lens group 30 at least five times. When the second lens group 30 is specifically disposed, the length of the second lens group 30 along the second optical axis is less than 9mm, the height of the second lens group 30 along the first optical axis is less than 7mm, and the total volume is less than 820 cubic centimeters.

As shown in fig. 3, when the light reflects the folded light path for multiple times, the back intercept is greatly reduced, the telescopic ratio | TTL/f |, of the camera module is 0.54, and the ratio | BFL/f |, of the back intercept to the effective focal length of the camera module is 0.36, so as to reduce the total length of the camera module;

TABLE 1A

Focal length	31
		F value	5.2
Half FOV	4.6°
		Total track length TTL	16.8
Telephoto ratio TTL/f	0.78
		Design wavelength	650nm，610nm，555nm，510nm，470nm

TABLE 1B

TABLE 1C

S#	K	A	B	C	D
						8	0	4.54E-04	4.59E-05	-4.64E-06	3.11E-07
9	0	2.53E-03	-1.89E-04	1.06E-05	2.05E-07
						10	0	-6.97E-04	-7.52E-04	9.35E-05	-3.76E-06
11	0	-5.80E-03	-1.08E-03	1.76E-04	-1.34E-05

In the structure shown in fig. 3, the second lens group 30 is disposed between the first lens group 20 and the photoreceptor 40, so that light is reflected and folded for multiple times, the incident angle of the light entering the second lens group 30 from the first lens group 20 is optimally adjusted, and the total-field light is reflected at least five times by setting the inclination angle and the refractive index parameter of the second lens group 30, wherein total reflection is achieved for more than two times, the physical length of the camera module on the second optical axis is effectively reduced, and the size of the camera module is reduced. In addition, the imaging lens assembly composed of at least one aspheric lens is adopted in the first lens group 20 and the second lens group 30, a first lens L1 with positive focal power and a second lens L2 with negative focal power are adopted, the refractive index Nd of the material of the first lens L1 and the material of the second lens L2 is more than or equal to 1.55, and the Abbe number Vd of the second lens L2 is less than or equal to 32; in addition, the aspheric lens uses the edge-removed lens along the height direction of the module, and the lens barrel and the bracket are integrally injection-molded, so that the height dimension of the module can be controlled to be less than 7 mm.

As shown in fig. 4, fig. 4 shows an XZ plane (a plane parallel to the base plate 50 in fig. 1) view of a camera module, which is designed to cover a visible spectrum of 470nm to 650nm, on the second optical axis. The camera module comprises a reflector 10 for folding an optical axis, and is arranged in an object space of the mirror assembly to fold light from the first optical axis to the second optical axis.

With continued reference to fig. 4, the first lens group 20 includes a first lens L1 with positive power, a second lens L2 with negative power, and a third lens L3 with negative power. And the aperture stop is located in front of the first lens L1. The lens is characterized in that a first lens L1 with positive focal power, a second lens L2 with negative focal power and a third lens L3 with negative focal power are adopted, the refractive index Nd of materials of the first lens L1 and the second lens L2 is more than or equal to 1.55, the Abbe number Vd of the second lens L2 is less than or equal to 32, and the Abbe number Vd of the third lens L3 is more than or equal to 50; the imaging quality of the camera module is further improved through reasonable optimization configuration. Tables 2A-2C, wherein tables 2A-2C provide various optical and physical parameter values for the camera module shown in fig. 4, provide sufficient telephoto focal length and a small chief ray angle.

TABLE 2A

TABLE 2B

TABLE 2C

S#	K	A	B	C	D
						8	0	6.59E-05	8.64E-06	0	0
9	0	8.58E-04	-2.54E-05	0	0
						10	0	-5.74E-04	-1.50E-05	0	0
11	0	-2.19E-03	-7.37E-06	0	0
						12	0	-4.69E-04	-7.20E-06	0	0
13	0	-6.56E-05	1.37E-05	0	0

When the camera module is used, the second lens group 30 reflects the light in the full field of view at least five times; multiple reflection folding light path greatly reduces intercept behind the optics, realizes camera module telescope ratio | TTL/f | ═ 0.56, and intercept and effective focal length's ratio | BFL/f | ═ 0.38 behind the camera module to reduce periscopic camera module overall length.

As shown in fig. 5, fig. 5 shows an XZ plan view on the second optical axis of the camera module designed to cover the visible spectrum of 470nm to 650 nm. The camera module comprises a reflector 10 for folding an optical axis, and is arranged in an object space of the mirror assembly to fold light from the first optical axis to the second optical axis.

With continued reference to fig. 5, the first lens group 20 includes a first lens L1 having a positive power and a second lens L2 having a negative power, and a stop is located in front of the first lens L1. The refractive index Nd of the material of the first lens L1 is more than or equal to 1.53, the refractive index Nd of the material of the second lens L2 is more than or equal to 1.62, the Abbe number Vd is less than or equal to 25, and the material of the first lens L1 and the material of the second lens L2 can be optical resin.

Referring to tables 3A-3C together, tables 3A-3C show various optical and physical parameter values for the camera module shown in fig. 5 that provide sufficient telephoto focal length and a small chief ray angle.

TABLE 3A

Focal length	31
		F value	4.8
Half FOV	4.55°
		Total track length TTL	21.4
Telephoto ratio TTL/f	0.8
		Design wavelength	650nm，610nm，555nm，510nm，470nm

TABLE 3B

TABLE 3C

S#	K	A	B	C	D
						1	0	1.58E-03	-5.95E-05	2.41E-06	6.49E-08
2	0	7.22E-03	-8.02E-04	5.45E-05	-1.18E-06
						3	0	6.97E-03	-1.81E-03	1.55E-04	-5.37E-06
4	0	1.86E-03	-2.61E-03	2.97E-04	-1.73E-05

In the above structure, the second lens group 30 makes the full field light undergo at least five reflections; multiple reflection folding light path greatly reduces intercept behind the optics, realizes camera module telescope ratio | TTL/f | ═ 0.69, and intercept and effective focal length's ratio | BFL/f | ═ 0.34 behind the camera module to reduce periscopic camera module overall length.

As shown in fig. 6, fig. 6 shows an XZ plan view on the second optical axis of the camera module designed to cover the visible spectrum of 470nm to 650 nm. The camera module comprises a reflector 10 for folding an optical axis, and is arranged in an object space of the mirror assembly to fold light from the first optical axis to the second optical axis.

The first lens group 20 includes a first lens L1 with positive power and a second lens L2 with negative power. The diaphragm is positioned in front of the first lens L1, wherein a first lens L1 with positive focal power and a second lens L2 with negative focal power are adopted, the refractive index Nd of the material of the first lens L1 is more than or equal to 1.53, the refractive index Nd of the material of the second lens L2 is more than or equal to 1.62, and the Abbe number Vd is less than or equal to 25. And when the reflector 10 is disposed, it is disposed between two lenses of the first lens group 20, as shown in fig. 6, the reflector 10 is disposed between the first lens L1 and the second lens L2, and refracts the light from the first optical axis to the second optical axis, which is beneficial to enlarging the aperture and shortening the total length of the camera module.

Referring collectively to tables 4A-4C, tables 4A-4C provide various optical and physical parameter values for a camera module as shown in fig. 6, which provides a sufficient telephoto focal length and a small chief ray angle.

The second lens group 30 can be formed by combining two prism elements, the refractive index Nd of the prism is more than or equal to 1.8, and an air gap which is not 0 is formed between the prism elements along the optical axis, so that the full-field light entering the second lens group 30 through the first lens group 20 can be totally reflected at least twice in the second lens group 30; the length of the second lens group 30 along the second optical axis is less than 9mm, the height along the first optical axis is less than 7mm, and the total volume is less than 820 cubic centimeters.

TABLE 4A

Focal length	31
		F value	5.0
Half FOV	4.5°
		Total track length TTL	19.6
Telephoto ratio TTL/f	0.63
		Design wavelength	650nm，610nm，555nm，510nm，470nm

TABLE 4B

TABLE 4C

S#	K	A	B	C	D
						1	0	-2.60E-03	2.11E-04	-1.40E-05	1.88E-07
2	0	-3.12E-03	2.97E-04	-2.05E-05	4.21E-07
						3	0	-7.67E-03	1.89E-03	-2.49E-04	1.25E-05
4	0	-8.85E-03	2.49E-03	-3.92E-04	2.32E-05

In the structure shown in FIG. 6, the second lens group 30 reflects the full field light at least five times; multiple reflection folding light path greatly reduces intercept behind the optics, realizes camera module telescope ratio | TTL/f | ═ 0.63, and intercept and effective focal length's ratio | BFL/f | ═ 0.34 behind the camera module to reduce periscopic camera module overall length.

As shown in fig. 7, fig. 7 is a YZ plan view of the miniaturized periscopic camera module 500 on a second optical axis, a compact imaging lens camera module designed to cover the visible spectrum of 470nm to 650 nm; the device comprises a reflector 10 for turning an optical axis, wherein the reflector 10 can be arranged between lenses of a mirror assembly to turn light rays from a first optical axis to a second optical axis;

the first lens group 20 comprises a first lens L1 with positive focal power and a second lens L2 with negative focal power, the diaphragm is positioned in front of the first lens L1, the first lens L1 with positive focal power and the second lens L2 with negative focal power are adopted, the first lens L1 is made of materials with refractive index Nd being more than or equal to 1.53, the second lens L2 is made of materials with refractive index Nd being more than or equal to 1.62, and the Abbe number Vd is less than or equal to 25; and when the reflector 10 is disposed between the two lenses of the first lens group 20, as shown in fig. 7, the reflector 10 is disposed between the first lens L1 and the second lens L2, and refracts the light from the first optical axis to the second optical axis, which is beneficial to enlarging the aperture and shortening the total length of the camera module.

Tables 5A-5C provide various optical and physical parameter values for camera module 500 as shown in fig. 8, which provides a sufficient telephoto focal length and a small chief ray angle.

3. A second lens group 30 for multiple reflection to fold the light path, wherein the light is reflected at the second lens group 30 at least five times;

the second lens group 30 can be formed by combining two prism elements, the refractive index Nd of the prism is more than or equal to 1.8, and an air gap with a value different from 0 is formed between the prism elements along the optical axis, so that the full-field light entering the second lens group 30 through the first lens group 20 can be totally reflected at least twice in the second lens group 30; the length of the second lens group 30 along the second optical axis is less than 9mm, the height along the first optical axis is less than 7mm, and the total volume is less than 820 cubic centimeters.

TABLE 5A

Focal length	40mm
		F value	6.22
Half FOV	3.6°
		Total track length TTL	24.8
Telephoto ratio TTL/f	0.62
		Design wavelength	650nm，610nm，555nm，510nm，470nm

TABLE 5B

TABLE 5C

S#	K	A	B	C	D
						1	0	-2.61E-03	2.25E-04	-1.33E-05	2.12E-07
2	0	-2.94E-03	3.08E-04	-1.95E-05	4.02E-07
						3	0	-5.90E-03	1.83E-03	-2.30E-04	1.06E-05
4	0	-7.68E-03	2.67E-03	-3.97E-04	2.17E-05

When the structure as shown in fig. 7 is adopted, the configuration of the parameters of the lens is reasonable, the telescopic ratio | TTL/f | -0.62 of the camera module can be kept while the focal length f is larger than or equal to 40mm, the ratio | BFL/f | -0.37 of the rear intercept of the camera module and the effective focal length is kept, and the total length of the periscopic camera module is reduced.

As can be seen from the above description, when the first lens group 20, the second lens group 30 and the reflecting mirror 10 are specifically arranged, they can be arranged as required. However, the first lens group 20 and the second lens group 30 are arranged from the object side to the image side. In the second lens group 30, only two specific first prisms 31 and second prisms 32 will be exemplified. However, in practical arrangement, the first prism 31 and the second prism 32 may include other surfaces besides the above-mentioned surfaces, for example, the first prism 31 is provided with a light incident surface 311, a second reflecting surface and at least one first reflecting surface; the second prism 32 is provided with two second reflecting surfaces opposite to each other and at least one first reflecting surface. The light path can be changed by arranging more reflecting surfaces, and the length of the camera module is shortened.

In the above embodiments, the provided reflector 10 can be implemented by using different mirrors, for example, the reflector 10 can be a plane mirror or a prism, but also can be other mirrors capable of reflecting light.

In addition, when the camera module is used, the shake easily occurs to influence the shooting effect. Therefore when setting up the camera module, as shown in fig. 8, this camera module still includes an anti-shake motor, and this anti-shake motor is used for driving speculum 10 and rotates, drives speculum 10 through the anti-shake motor and rotates along different axes to realize the effect of anti-shake. In a specific arrangement, the anti-shake motor can be a different motor, such as a shape memory alloy wire motor, an electromagnetic motor or a piezoelectric motor. Taking an electromagnetic motor as an example, as shown in fig. 8, when the electromagnetic motor is installed, the reflector 10 is installed on the bracket 60, and the piezoelectric motor 70 includes two sets of coils 71 and two sets of magnets 72, and the coils and the magnets cooperate to drive the prism to rotate around the optical axis and around the point axis, so that the optical shake prevention of the camera module can be realized.

Of course, besides the above-mentioned anti-shake motor, the anti-shake can be realized by other ways, as shown in fig. 9, in the structure shown in fig. 9, the camera module further includes a variable curved lens 80 located on the side of the first lens group 20 close to the object side. In fig. 9, a variable curved lens 80 is disposed between the first lens group 20 and the reflecting mirror 10, and the anti-shake effect is achieved by changing the curved surface of the variable curved lens 80. In a specific implementation, the variable-curvature lens is a liquid lens. This liquid camera lens has the rete of a encapsulation liquid and drives this rete and take place the driver of deformation, thereby takes place deformation through the different positions that the driver drove the rete and can realize the effect of anti-shake. Of course, when the anti-shake effect is realized, the anti-shake effect can be realized by the variable curved lens 80 alone, or by the anti-shake motor, and the anti-shake effect can be improved by applying the two methods together.

In addition, the liquid lens can be used for realizing focusing besides being used for anti-shaking, and when the liquid lens is used for focusing, the driver drives the membrane material to stretch and retract so as to achieve the focusing effect.

Besides the above focusing method, the first lens group 20 can be used to realize focusing. When the focusing mechanism is specifically arranged, focusing is realized by adopting a mode that the first lens group 20 can move along the optical axis relative to the bottom plate 10, the camera module is further provided with a driving motor for driving the first lens group 20 to move, and when the focusing mechanism is used, the driving motor is arranged to drive the position of the first lens group 20 so as to realize focusing. The drive motor may be a motor capable of driving the component to move, as is common in the art. Of course, in addition to the above, focusing can also be achieved by driving a lens in the first lens group 20 close to the second lens group 30 to move, for example, when the first lens group 20 is specifically configured, the first lens group 20 includes a first lens L1 and a second lens L2, wherein the second lens L2 is located between the first lens L1 and the second lens group 30, and when the second lens L2 is configured, the second lens L2 can move along the optical axis (second optical axis) relative to the base plate 10. The focusing effect can also be achieved by arranging a driving motor to drive the second lens L2 to move.

In order to reduce the thickness of the entire camera module when the first lens group 20 and the second lens group 30 are disposed, the first lens group 20 is a flat lens group as shown in fig. 1. That is, the lenses in the first lens group 20 are flattened, if the lenses are arranged not in a circular shape as a common lens, but in a flat shape, the lenses are worth to have a plane facing the bottom plate 50 and a plane away from the bottom plate 50, and for the components in the first lens group 20, the circular lenses are cut to form two planes, so as to facilitate the packaging of the first lens group 20 on the bottom plate 50, and at the same time, the thickness of the first lens group 20 can be reduced. In addition, the second lens group 30 is a rhombic lens, which also has two planes facing to and away from the bottom plate 50, and when the second lens group 30 is disposed, the thickness of the first lens group 20 is approximately equal to the thickness of the second lens group 30, and the thickness refers to the thickness of the first lens group 20 and the second lens group 30 on the plane perpendicular to the bottom plate 50.

The embodiment of the application also provides a mobile terminal, which can be a common mobile terminal such as a mobile phone, a tablet computer, a notebook computer and the like. However, whichever mobile terminal is adopted, the mobile terminal comprises a shell and the camera module arranged in the shell. In the above technical scheme, by adding the second lens group 30 in the camera module, the second lens group 30 is provided with a plurality of reflecting surfaces and a transmissive surface, so that the path of the light can be folded when the light passes through the second lens L2 group, and the length of the camera module is further shortened, and the camera module with a larger focal length can be placed in the mobile terminal.

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

Claims

1. The utility model provides a camera module which characterized in that includes: the optical lens comprises a bottom plate, a reflecting mirror, a first lens group and a second lens group, wherein the reflecting mirror is packaged on the bottom plate and used for refracting an optical axis; the anti-shake device also comprises an anti-shake motor for driving the reflecting mirror to rotate; wherein the content of the first and second substances,

the second lens group comprises a plurality of reflecting surfaces for folding ray paths, and at least part of the reflecting surfaces in the plurality of reflecting surfaces are reflecting surfaces which are permeable to the rays when the rays are irradiated at a set angle.

2. The camera module according to claim 1, wherein the reflective surface comprises a first reflective surface and a second reflective surface, the second reflective surface being transparent to the light when the light is irradiated at a predetermined angle; wherein the number of the second reflecting surfaces is at least three.

3. The camera module according to claim 2, wherein the second lens group comprises a first prism and a second prism which are oppositely arranged; wherein the content of the first and second substances,

the first prism is provided with a light incident surface, a second reflecting surface and at least one first reflecting surface;

the second prism is provided with two opposite second reflecting surfaces and at least one first reflecting surface, wherein the second reflecting surface far away from the first prism is a light-emitting surface.

4. The camera module of claim 3, wherein said first prism has a second reflective surface disposed adjacent to said light incident surface,

the included angle between the second reflecting surface of the first prism and the light incident surface is within the range of 19.5-25.5 degrees.

5. The camera module according to claim 4, wherein the first prism is provided with a first reflection surface, and the first reflection surface and the second reflection surface are respectively arranged on two sides of the light incident surface; wherein the content of the first and second substances,

the included angle between the first reflecting surface of the first prism and the light incident surface is within the range of 109.5-115.5 degrees.

6. The camera module according to any one of claims 3 to 5, wherein the light exit surface of the second prism is parallel to the light entrance surface.

7. The camera module according to claim 6, wherein the second prism has a first reflection surface, and an included angle between the first reflection surface of the second prism and the light exit surface is within a range of 64.5 ° -70.5 °.

8. The camera module according to claim 7, wherein another second reflection surface of the second prism is adjacent to the first reflection surface and the light emitting surface, respectively; and the included angle between the other second reflecting surface of the second prism and the light-emitting surface is within the range of 42.5-48.5 degrees.

9. The camera module according to any one of claims 1 to 8, wherein a telescopic ratio of the camera module is: and | TTL/f | is less than or equal to 0.85.

10. The camera module of claim 9, wherein a ratio of a back intercept to an effective focal length of the camera module is: the | BFL/f | is less than or equal to 0.4.

11. The camera module according to any one of claims 1 to 10, wherein the reflector is a prism or a plane mirror; wherein the content of the first and second substances,

The prism or the plane mirror is positioned in front of the first lens group; or

The prism or the plane mirror is positioned between any two lenses of the first lens group.

12. The camera module according to any one of claims 1 to 11, further comprising a variable curved lens disposed on a side of the first lens group close to the object side.

13. The camera module of claim 12, wherein the variable camber lens is a liquid lens.

14. The camera module according to any one of claims 1 to 13, wherein the anti-shake motor is a shape memory alloy wire motor, an electromagnetic motor, or a piezoelectric motor.

15. The camera module according to any one of claims 1 to 14, wherein the first lens group is a flat lens group.

16. A mobile terminal, characterized by comprising a housing and the camera module according to any one of claims 1 to 15 disposed in the housing.