Optical system, imaging module, and electronic apparatus

Abstract

An optical system (30), wherein there are three or four lenses having refractive power in the optical system (30). The optical system (30) sequentially comprises, from an object side to an image side along an optical axis: a first lens (L1) having positive refractive power, both the object-side surface and image-side surface of the first lens (L1) being convex surfaces near the optical axis; a second lens (L2) having refractive power; and a third lens (L3) having refractive power, one of the second lens (L2) and the third lens (L3) having positive refractive power, and the other having negative refractive power. The optical system (30) satisfies the following condition expressions: 0.25≤f1 / f≤0.85, 0.15≤|f2 / f|≤0.45, and 0.15≤|f3 / f|≤1.25, wherein f1 is the focal length of the first lens (L1), f2 is the focal length of the second lens (L2), and f3 is the focal length of the third lens (L3).

Description

Optical systems, shooting modules and electronic equipment

[0001] Related applications

[0002] This application claims priority to Chinese patent application number 2023117294355, filed on December 14, 2023, entitled “Optical system, shooting module and electronic device,” the entire text of which is hereby incorporated by reference. Technical Field

[0003] The present application relates to the technical field of photographing devices, and in particular to an optical system, a photographing module and an electronic device. Background Art

[0004] An increasing number of electronic devices, such as smartphones, tablets, and e-readers, are equipped with camera modules to enable photography. To adapt the camera module's telephoto design to the electronic device's structural layout and reduce its thickness, periscope camera modules have emerged. These modules incorporate optical transmission elements such as prisms to deflect light, thereby reducing the module's overall size relative to the device's thickness. However, current telephoto camera modules struggle to achieve both miniaturization and good image quality. Summary of the Invention

[0005] According to various embodiments of the present application, an optical system, a shooting module and an electronic device are provided.

[0006] An optical system, wherein the number of lenses having refractive power in the optical system is three or four, and the optical system comprises, in order from the object side to the image side along the optical axis:

[0007] a first lens having positive refractive power, wherein both the object-side surface and the image-side surface of the first lens are convex at the near optical axis;

[0008] a second lens having refractive power; and

[0009] a third lens having a refractive power, wherein one of the second lens and the third lens has a positive refractive power and the other has a negative refractive power;

[0010] The optical system satisfies the following conditional formula:

[0011] 0.25≤f1 / f≤0.85;

[0012] 0.15≤|f2 / f|≤0.45;

[0013] 0.15≤|f3 / f|≤1.25;

[0014] Wherein, f1 is the focal length of the first lens, f2 is the focal length of the second lens, and f3 is the focal length of the third lens.

[0015] A shooting module, comprising an image sensor, an optical transmission element and the above-mentioned optical system;

[0016] The optical transmission element has a light-transmitting surface, and the light-transmitting surface is provided with a light entrance area and a light exit area. The light entrance area is opposite to the optical system, and the light exit area is opposite to the image sensor. The optical transmission element is used to reflect at least part of the light incident on the light entrance area at least twice and then emit it from the light exit area. The photosensitive surface of the image sensor is perpendicular to the axis of the optical system.

[0017] An electronic device includes the above-mentioned shooting module. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the conventional technology, the following briefly introduces the drawings required for use in the embodiments or the conventional technology descriptions. Obviously, the drawings described below are merely embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the disclosed drawings without any creative work.

[0019] FIG1 is a schematic structural diagram of an electronic device in some embodiments.

[0020] FIG2 is a schematic diagram of the optical path of a shooting module in some embodiments.

[0021] FIG3 is a schematic structural diagram of the shooting module in the first embodiment.

[0022] FIG. 4 is a graph showing spherical aberration, astigmatism, and distortion curves of the shooting module in the first embodiment.

[0023] FIG5 is a schematic structural diagram of a shooting module in the second embodiment.

[0024] FIG6 is a graph showing spherical aberration, astigmatism, and distortion curves of the shooting module in the second embodiment.

[0025] FIG. 7 is a schematic structural diagram of a shooting module in the third embodiment.

[0026] FIG8 is a graph showing spherical aberration, astigmatism, and distortion curves of the shooting module in the third embodiment.

[0027] FIG9 is a schematic structural diagram of a shooting module in the fourth embodiment.

[0028] FIG. 10 is a graph showing spherical aberration, astigmatism, and distortion curves of the shooting module in the fourth embodiment.

[0029] FIG11 is a schematic structural diagram of an electronic device including other components in some embodiments. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0031] As used herein, "electronic device" refers to a device that can receive and / or send communication signals, including but not limited to a device that is connected via any one or more of the following connection methods:

[0032] (1) Connection via a wired line, such as Public Switched Telephone Networks (PSTN), Digital Subscriber Line (DSL), digital cable, or direct cable connection;

[0033] (2) Via wireless interfaces, such as cellular networks, wireless local area networks (WLAN), digital television networks such as DVB-H networks, satellite networks, and AM-FM broadcast transmitters.

[0034] An electronic device configured to communicate via a wireless interface may be referred to as a "mobile terminal". Examples of mobile terminals include, but are not limited to, the following electronic devices:

[0035] (1) Satellite phone or cellular phone;

[0036] (2) Personal Communications System (PCS) terminals that can combine cellular radiotelephones with data processing, fax, and data communications capabilities;

[0037] (3) Radiotelephone, pager, Internet / Intranet access, Web browser, notepad, calendar, Personal Digital Assistant (PDA) equipped with a Global Positioning System (GPS) receiver;

[0038] (4) conventional laptop and / or palmtop receivers;

[0039] (5) Conventional laptop and / or palmtop radiotelephone transceivers, etc.

[0040] Traditional periscope camera modules typically use prisms to deflect light to shift the axial dimension of the optical system from the thickness direction to the width direction of the electronic device, thereby compressing the thickness of the electronic device. This arrangement causes the photosensitive surface of the image sensor to be parallel to the thickness direction of the electronic device, and the image sensor occupies the thickness space of the electronic device. However, as the industry's requirements for imaging module quality are getting higher and higher, the size of the imaging surface is also getting larger and larger. The increase in image sensor size will lead to an increase in the thickness of the electronic device. Traditional periscope camera modules have become difficult to achieve miniaturization and good imaging quality.

[0041] To solve the above problems, the present application provides an optical system, a shooting module and an electronic device.

[0042] Please refer to Figures 1 and 2. Figure 1 shows a schematic diagram of the structure of an electronic device 10 in some embodiments, and Figure 2 shows a schematic diagram of the optical path of a camera module 20 in some embodiments. The electronic device 10 provided in this application includes, but is not limited to, devices such as smartphones, tablet computers, e-readers, and wearable devices that can be equipped with a camera module 20 to provide a camera function. The electronic device 10 in the embodiments of this application is exemplified using a smartphone as an example.

[0043] In some embodiments, the electronic device 10 includes a housing 11 and a camera module 20. The camera module 20 is disposed in the housing 11. The electronic device 10 is provided with the camera module 20 to implement a camera function. In some embodiments, the housing 11 includes a middle frame, a display module, and a rear cover. The middle frame can be roughly rectangular. The display module and the rear cover can be respectively disposed on both sides of the middle frame to form a housing space together with the middle frame. The camera module 20 can be accommodated in the housing space of the housing 11. In this application, the direction of the display module of the housing 11 pointing to the rear cover can be regarded as the thickness direction of the electronic device 10.

[0044] In some embodiments, the camera module 20 includes an optical system 30 and an image sensor 22. The optical system 30 includes multiple lenses with refractive power. The photosensitive surface of the image sensor 22 can overlap with the imaging surface 32 of the optical system 30. Light received by the camera module 20 is conditioned by the optical system 30 and can be projected onto the image sensor 22 to form an image. The image sensor 22 includes, but is not limited to, a charge coupled device (CCD) or a complementary metal-oxide semiconductor (CMOS) sensor.

[0045] Furthermore, in some embodiments, the optical system 30 includes three or four lenses having refractive power. The optical system 30 includes, from the object side to the image side along the optical axis, a first lens L1 having positive refractive power, a second lens L2 having refractive power, and a third lens L3 having refractive power. One of the second lens L2 and the third lens L3 has positive refractive power, while the other has negative refractive power. Both the object-side and image-side surfaces of the first lens L1 are convex near the optical axis. The optical system 30 further satisfies the following conditions: 0.25 ≤ f1 / f ≤ 0.85; 0.15 ≤ |f2 / f| ≤ 0.45; and 0.15 ≤ |f3 / f| ≤ 1.25. Here, f1 is the focal length of the first lens L1, f2 is the focal length of the second lens L2, and f3 is the focal length of the third lens L3.

[0046] In some embodiments, the optical system 30 further includes a fourth lens L4 positioned on the image side of the third lens L3. The fourth lens L4 has positive refractive power, and one of the object-side and image-side surfaces of the fourth lens L4 is convex near the optical axis, while the other is concave near the optical axis. The lenses in the optical system 30 can be coaxially arranged, with the common axis of the lenses serving as the axis of the optical system 30. The optical axis of the camera module 20 overlaps with the axis of the optical system 30 in the portion of the optical system 30. Light received by the optical system 30 is sequentially modulated by the first lens L1, the second lens L2, the third lens L3, and the fourth lens L4 before being incident on the imaging surface 32 of the optical system 30, i.e., the image sensor 22.

[0047] In the aforementioned optical system 30, first lens L1 has positive focal power. Combined with its biconvex shape at the near optical axis and the aforementioned design regarding f1 / f, first lens L1 possesses suitable refractive power to focus incident light, thereby shortening the overall length of optical system 30 without introducing excessive aberrations. The combination of positive and negative focal powers of second lens L2 and second lens L2, combined with the aforementioned designs regarding |f2 / f| and |f3 / f|, enables second lens L2 and third lens L3 to smoothly deflect light collected by first lens L1, reducing the angle of deflection at second lens L2 and third lens L3. When optical system 30 comprises four lenses, the combination of second lens L2 and third lens L3 also helps reduce the angle of deflection borne by fourth lens L4, thereby facilitating correction of aberrations in the peripheral field of view and improving the imaging quality of optical system 30. The positive refractive power of fourth lens element L4, combined with the design of one convex object-side surface and one concave image-side surface of fourth lens element L4, further converges light, shortening the axial dimension of optical system 30. This also helps increase the back focal length of optical system 30, achieving a telephoto design. Thus, through the appropriate design of the focal power, surface shape, and focal length of each lens element, the optical system 30 can achieve both compactness and good imaging quality, whether comprising three or four lenses.

[0048] In some embodiments, when the second lens element L2 has positive refractive power, both the object-side and image-side surfaces of the second lens element L2 are convex at the near optical axis. When the second lens element L2 has negative refractive power, both the object-side and image-side surfaces of the second lens element L2 are concave at the near optical axis. When the third lens element L3 has negative refractive power, both the object-side and image-side surfaces of the third lens element L3 are concave at the near optical axis. When the third lens element L3 has positive refractive power, the object-side surface of the third lens element L3 is convex at the near optical axis. Thus, by properly configuring the refractive power and surface shape of the second and third lens elements L2 and L3, the degree of light deflection on each surface of the second and third lens elements L2 and L3 can be reduced, and marginal aberrations can be suppressed, thereby improving the imaging quality of the optical system 30.

[0049] In some embodiments, when the optical system 30 includes a fourth lens element L4, the optical system 30 satisfies the conditional equation: 0.9 ≤ f4 / f ≤ 1.2, where f4 is the focal length of the fourth lens element L4. When this conditional equation is satisfied, the refractive power and surface profile of the fourth lens element L4 can be optimally configured, thereby reducing the overall length of the optical system 30 while increasing the back focal length of the optical system 30, thereby achieving a telephoto design.

[0050] In some embodiments, the optical system 30 satisfies the condition: 0.145 mm -1 ≤FNO / f≤0.195mm -1 Wherein, FNO is the aperture number of the optical system 30. When the above conditional expression is satisfied, the ratio of the aperture number to the focal length of the optical system 30 can be reasonably configured, so that the optical system 30 has sufficient light input, which is conducive to improving the imaging brightness of the optical system 30 and improving the imaging quality of the optical system 30 in low-light environments.

[0051] In some embodiments, the optical system 30 satisfies the conditional equation: 1.3 ≤ TTL / f ≤ 1.5, where TTL is the distance along the optical axis from the object-side surface of the first lens element L1 to the imaging surface 32 of the optical system 30, i.e., the total optical length of the optical system 30. Meeting this conditional equation allows for a reasonable ratio between the total optical length and focal length of the optical system 30, facilitating a balanced adjustment of the axial dimension and effective focal length of the optical system 30, thereby achieving telephoto characteristics while simultaneously compressing the axial dimension of the optical system 30.

[0052] In some embodiments, the shooting module 20 also includes an optical conduction element 21, which is arranged along the optical path between the optical system 30 and the image sensor 22. The optical conduction element 21 can play a role in light path conduction between the optical system 30 and the image sensor 22, and transmit the light emitted by the optical system 30 to the image sensor 22 after at least two reflections, thereby realizing a periscope design, which is conducive to compressing the size of the shooting module 20 in the thickness direction of the electronic device 10.

[0053] In some embodiments, the optical transmission element 21 has a light-transmitting surface 211, which is provided with a light-entry area 2111 and a light-exiting area 2112. The light-entry area 2111 is opposite the optical system 30, while the light-exiting area 2112 is opposite the image sensor 22. The optical transmission element 21 is configured to reflect at least a portion of the light incident on the light-entry area 2111 (i.e., emitted by the optical system 30 onto the optical transmission element 21) at least twice before emitting the light from the light-exiting area 2112. In other words, the optical transmission element 21 is capable of deflecting the light path by 180°, such that the photosensitive surface of the image sensor 22 is perpendicular to the axis of the optical system 30, thereby shifting the extension direction of the image sensor 22 from the thickness direction of the electronic device 10 to the width or length direction of the electronic device 10. The axial direction of the optical system 30 is parallel to the thickness direction of the electronic device 10.

[0054] Thus, the aforementioned camera module 20 is provided with an optical transmission element 21 that deflects the optical path by 180°, so that the photosensitive surface of the image sensor 22 does not occupy the thickness dimension of the electronic device 10. Even if the imaging surface 32 of the optical system 30 is increased, and the size of the image sensor 22 is increased, the size of the camera module 20 in the width direction of the electronic device 10 is only increased, without increasing the thickness dimension of the electronic device 10. Furthermore, the sizes of the optical system 30 and the image sensor 22 at least partially overlap in the axial direction of the optical system 30. This achieves a large image plane design to improve imaging quality while also facilitating a reduction in the thickness dimension of the electronic device 10, thereby achieving both miniaturization and good imaging quality. Furthermore, although the axial direction of the optical system 30 is parallel to the thickness direction of the electronic device 10, the aforementioned optical system 30 can achieve a telephoto effect and good imaging quality by utilizing three or four lenses through the appropriate design of each lens element, thereby facilitating a reduction in the axial dimension of the optical system 30 and the thickness dimension of the electronic device 10.

[0055] The specific configuration of the optical transmission element 21 is not limited, as long as it can bend the optical path by 180° to shift the extension direction of the image sensor 22 from the thickness direction of the electronic device 10 to the width direction. In some embodiments, the optical transmission element 21 further includes a first reflective surface 212 and a second reflective surface 213. Both the first reflective surface 212 and the second reflective surface 213 are inclined relative to the light-transmitting surface 211. The first reflective surface 212 is positioned corresponding to the light-entering region 2111, and the second reflective surface 213 is positioned corresponding to the light-exiting region 2112. At least a portion of the light entering the optical transmission element 21 from the light-entering region 2111 can strike the first reflective surface 212 and be reflected by the first reflective surface 212 to the side of the light-transmitting surface 211 facing away from the optical system 30. Thereafter, the light is reflected by the light-transmitting surface 211 to the second reflective surface 213. The light is then reflected by the second reflective surface 213 to the light-exiting region 2112, and then emitted from the light-exiting region 2112 to the image sensor 22. In other words, the optical transmission element 21 is used to reflect light incident from the light entrance area 2111 sequentially through the first reflective surface 212, the light-transmitting surface 211, and the second reflective surface 213, before emitting from the light exit area 2112. This three-fold reflection folds the light path, accommodating the telephoto design of the optical system 30. This periscope design achieves this telephoto design while also reducing the space occupied by the camera module 20.

[0056] The inclination angles of the first reflective surface 212 and the second reflective surface 213 relative to the light-transmitting surface 211 are not limited, as long as the light can be deflected 180° after being reflected by the first reflective surface 212, the second reflective surface 213 and the light-transmitting surface 211. For example, the angles of the first reflective surface 212 and the second reflective surface 213 relative to the light-transmitting surface 211 can be 25°-35°, for example, 32.5°.

[0057] It is understood that the ends of the first reflective surface 212 and the second reflective surface 213 away from the light-transmitting surface 211 may be connected. Referring to FIG. 2 , in some embodiments, effective light incident on the optical transmission element 21 does not pass through the portions of the first reflective surface 212 and the second reflective surface 213 away from the light-transmitting surface 211. Therefore, in some embodiments, the optical transmission element 21 further includes a bottom surface 214, which is opposite the light-transmitting surface 211 and connects the first reflective surface 212 and the second reflective surface 213. By forming the bottom surface 214 by cutting the end of the optical transmission element 21 away from the optical system 30, the dimension of the optical transmission element 21 in the thickness direction of the electronic device 10 can be reduced without affecting light transmission, thereby facilitating a reduction in the thickness of the electronic device 10.

[0058] In some embodiments, the optical system 30 may further include an aperture STO disposed on the object side of the first lens L1, and the aperture STO is used to constrain the aperture of the light. The shooting module 20 may further include an infrared filter 31 disposed between the optical transmission element 21 and the imaging surface 32, and the infrared filter 31 is used to filter out interference light of the infrared light to prevent the interference light from being projected onto the imaging surface 32 and affecting normal imaging.

[0059] In some embodiments, the camera module 20 satisfies the conditional equation: 0.82 ≤ E1 / H ≤ 1.6, where E1 is the distance between the boundary between the first and second reflective surfaces 212 and 213 (when the first and second reflective surfaces 212 and 213 are in contact), or the boundary between the extended surfaces of the first and second reflective surfaces 212 and 213 (when the first and second reflective surfaces 212 and 213 are in contact with the bottom surface 214), and the light-transmitting surface 211 in the axial direction of the optical system 30, and H is the axial dimension of the optical system 30. Meeting this conditional equation allows for optimal design of the dimensions of the optical system 30 and the optical transmission element 21, thereby reducing the dimension of the camera module 20 in the thickness direction of the electronic device 10.

[0060] In some embodiments, the camera module 20 satisfies the conditional equation: 0.7 ≤ E2 / E1 ≤ 0.95, where E2 is the distance between the bottom surface 214 and the light-transmitting surface 211 in the axial direction of the optical system 30, and E1 is the distance between the boundary between the first reflective surface 212 and the second reflective surface 213, or between the boundary between the first reflective surface 212 and the extended surface of the reflective surface, and the light-transmitting surface 211 in the axial direction of the optical system 30. When this conditional equation is satisfied, the bottom surface 214 can be positioned appropriately on the optical transmission element 21 along the axial direction of the optical system 30, effectively reducing the size of the optical transmission element 21 in the thickness direction of the electronic device 10 while maintaining light transmission.

[0061] In some embodiments, the camera module 20 satisfies the following conditions: 0.4 mm / ° ≤ C / α1 ≤ 0.5 mm / °; 3 ≤ α2 / α1 ≤ 4.1, where C is the thickness of the optical transmission element 21 equivalent to flat glass, i.e., the length of the optical axis within the optical transmission element 21; α1 is the angle between the light-transmitting surface 211 and the first reflective surface 212; and α2 is the angle between the first reflective surface 212 and the second reflective surface 213. Meeting these conditions allows for optimal configuration of the thickness of the optical transmission element 21 equivalent to flat glass, the angle between the light-transmitting surface 211 and the first reflective surface 212, and the angle between the first reflective surface 212 and the second reflective surface 213. This allows for optimal planning of the light transmission path within the optical transmission element 21, effectively folding the light path. This allows for a compact footprint of the optical transmission element 21 while accommodating the telephoto design of the optical system 30.

[0062] Based on the description of the above embodiments, more specific embodiments and drawings are presented below for detailed description.

[0063] First embodiment

[0064] Please refer to Figure 3, which is a schematic diagram of the structure of the camera module 20 in the first embodiment. The camera module 20 includes, from the object side to the image side, an aperture stop STO, a first lens L1 with positive refractive power, a second lens L2 with positive refractive power, a third lens L3 with negative refractive power, a fourth lens L4 with positive refractive power, and an optical transmission element 21. In this embodiment and the following embodiments, the materials of the lenses and the optical transmission element 21 include, but are not limited to, any suitable material, such as glass or plastic.

[0065] The object-side surface and image-side surface of the first lens L1 are both convex at the near optical axis;

[0066] The object-side surface and image-side surface of the second lens L2 are both convex at the near optical axis;

[0067] The object-side surface and image-side surface of the third lens L3 are both concave at the near optical axis;

[0068] The object-side surface of the fourth lens L4 is concave at the near optical axis, and the image-side surface is convex at the near optical axis.

[0069] Table 1 lists the various parameters of the camera module 20 in the first embodiment. The components from the object plane to the imaging plane 32 are arranged in the order listed in Table 1 from top to bottom. The Y radius in Table 1 represents the radius of curvature of the corresponding object-side or image-side surface at the optical axis. The first value in the "Thickness" column for the first lens L1 represents the thickness of the lens along the optical axis, and the second value represents the distance along the optical axis from the image-side surface to the next surface of the lens in the image-side direction.

[0070] It should be noted that, in this embodiment and the following embodiments, the optical system 30 may also be provided with the infrared filter 31, but in this case the distance from the image side surface of the fourth lens L4 (or the third lens L3) to the imaging surface 32 remains unchanged.

[0071] Table 1

[0072] In the first embodiment and the following embodiments, the object side and image side of each lens in the optical system 30 are aspherical surfaces. The aspheric coefficients of the object side or image side of each lens of the optical system 30 in the first embodiment are given in Table 2. Among them, the surface numbers from 1 to 8 respectively represent the object side of the first lens L1, the image side of the first lens L1, the object side of the second lens L2, the image side of the second lens L2, and so on to the image side of the fourth lens L4. And K-A30 from top to bottom respectively represent the type of aspheric coefficient, wherein K represents the cone coefficient, A4 represents the fourth-order aspheric coefficient, A6 represents the sixth-order aspheric coefficient, A8 represents the eighth-order aspheric coefficient, and so on. In addition, the aspheric coefficient formula is as follows:

[0073] Wherein, z is the distance vector height from the vertex of the aspheric surface when the aspheric surface is at a height of h along the optical axis; c is the paraxial curvature of the aspheric surface, c = 1 / R (paraxial curvature c is the inverse of the curvature radius R); k is the conic coefficient; Ai is the correction coefficient of the i-th order aspheric surface.

[0074] Table 2

[0075] Please refer to Figure 4, which shows, from left to right, the longitudinal spherical aberration curve, the astigmatism curve, and the distortion curve of the shooting module 20 in the first embodiment. Among them, the longitudinal spherical aberration curve represents the deviation of the convergent focus of light of different wavelengths after passing through the lens, wherein the ordinate represents the normalized pupil coordinate (Normalized Pupil Coordinator) from the center of the pupil to the edge of the pupil, and the abscissa represents the focus offset, that is, the distance from the imaging surface 32 to the intersection of the light and the optical axis (in mm). It can be seen from the longitudinal spherical aberration diagram that the degree of deviation of the convergent focus of light of each wavelength in the first embodiment tends to be consistent, and the diffuse spots or color halos in the imaging picture are effectively suppressed. In the astigmatism curve diagram (ASTIGMATIC FIELD CURVES), the abscissa represents the focus offset and the ordinate represents the image height, in mm. It can be seen from the astigmatism curve diagram that the field curvature of the shooting module 20 is small, the field curvature and astigmatism of each field of view are well corrected, and the center and edge of the field of view have clear imaging. The distortion curve (DISTORTION) shows the distortion values ​​for different field of view angles. The horizontal axis represents the distortion value (in %), and the vertical axis represents the image height (in mm). As can be seen from the figure, the image distortion caused by the main beam is minimal, indicating that the image quality of the camera module 20 is excellent.

[0076] Second embodiment

[0077] Please refer to Figure 5, which is a schematic structural diagram of the shooting module 20 in the second embodiment. The shooting module 20 includes, from the object side to the image side, an aperture STO, a first lens L1 with positive refractive power, a second lens L2 with negative refractive power, a third lens L3 with positive refractive power, a fourth lens L4 with positive refractive power, and an optical transmission element 21.

[0078] The object-side surface and image-side surface of the first lens L1 are both convex at the near optical axis;

[0079] The object-side surface and image-side surface of the second lens L2 are both concave at the near optical axis;

[0080] The object-side surface of the third lens L3 is convex at the near optical axis, and the image-side surface is concave at the near optical axis.

[0081] The object-side surface of the fourth lens L4 is convex at the near optical axis, and the image-side surface is concave at the near optical axis.

[0082] The various parameters of the shooting module 20 in the second embodiment are given in Table 3, and the meaning of each parameter can be obtained by referring to the first embodiment.

[0083] Table 3

[0084] The aspheric coefficients of the object side or image side of each lens of the optical system 30 in the second embodiment are given in Table 4, where the meanings of each parameter can be obtained by referring to the first embodiment.

[0085] Table 4

[0086] Please refer to Figure 6 , which shows, from left to right, the longitudinal spherical aberration curve, astigmatism curve, and distortion curve of the camera module 20 in the second embodiment. As can be seen from Figure 6 , the longitudinal spherical aberration, astigmatism, and distortion of the camera module 20 are all well controlled, resulting in excellent imaging quality for the camera module 20 of this embodiment.

[0087] Third embodiment

[0088] Please refer to Figure 7, which is a schematic structural diagram of the shooting module 20 in the third embodiment. The shooting module 20 includes, from the object side to the image side, an aperture STO, a first lens L1 with positive refractive power, a second lens L2 with negative refractive power, a third lens L3 with positive refractive power, a fourth lens L4 with positive refractive power, and an optical transmission element 21.

[0089] The object-side surface and image-side surface of the first lens L1 are both convex at the near optical axis;

[0090] The object-side surface and image-side surface of the second lens L2 are both concave at the near optical axis;

[0091] The object-side surface of the third lens L3 is convex at the near optical axis, and the image-side surface is concave at the near optical axis.

[0092] The object-side surface of the fourth lens L4 is concave at the near optical axis, and the image-side surface is convex at the near optical axis.

[0093] The various parameters of the shooting module 20 in the third embodiment are given in Table 5, and the meaning of each parameter can be obtained by referring to the first embodiment.

[0094] Table 5

[0095] The aspheric coefficients of the object side or image side of each lens of the optical system 30 in the third embodiment are given in Table 6, where the meanings of each parameter can be obtained by referring to the first embodiment.

[0096] Table 6

[0097] Please refer to Figure 8 , which shows, from left to right, the longitudinal spherical aberration curve, astigmatism curve, and distortion curve of the camera module 20 in the third embodiment. As can be seen from Figure 8 , the longitudinal spherical aberration, astigmatism, and distortion of the camera module 20 are all well controlled, resulting in excellent imaging quality for the camera module 20 of this embodiment.

[0098] Fourth embodiment

[0099] Please refer to Figure 9, which is a schematic structural diagram of the shooting module 20 in the fourth embodiment. The shooting module 20 includes, from the object side to the image side, an aperture STO, a first lens L1 with positive refractive power, a second lens L2 with negative refractive power, a third lens L3 with positive refractive power, and an optical transmission element 21.

[0100] The object-side surface and image-side surface of the first lens L1 are both convex at the near optical axis;

[0101] The object-side surface and image-side surface of the second lens L2 are both concave at the near optical axis;

[0102] Both the object-side surface and the image-side surface of the third lens L3 are convex surfaces at the near optical axis.

[0103] The various parameters of the shooting module 20 in the fourth embodiment are given in Table 7, and the meaning of each parameter can be obtained by referring to the first embodiment.

[0104] Table 7

[0105] The aspheric coefficients of the object side or image side of each lens of the optical system 30 in the fourth embodiment are given in Table 8, where the meanings of the various parameters can be obtained by referring to the first embodiment.

[0106] Table 8

[0107] Please refer to Figure 10 , which shows, from left to right, the longitudinal spherical aberration curve, astigmatism curve, and distortion curve of the camera module 20 in the fourth embodiment. As can be seen from Figure 10 , the longitudinal spherical aberration, astigmatism, and distortion of the camera module 20 are all well controlled, resulting in excellent imaging quality for the camera module 20 of this embodiment.

[0108] In some embodiments, the shooting module 20 also satisfies the data in Table 9 below, where FOV is the maximum field of view angle of the shooting module 20. The remaining conditional expressions and the effects that can be obtained by satisfying the following data can be obtained by referring to the above records and will not be repeated here.

[0109] Table 9

[0110] Referring to Figure 11, Figure 11 is a schematic diagram of the structure of an electronic device 10 provided in an embodiment of the present application. The electronic device 10 may include a radio frequency (RF) circuit 501, a memory 502 including one or more computer-readable storage media, an input unit 503, a display unit 504, a sensor 505, an audio circuit 506, a wireless fidelity (WiFi) module 507, a processor 508 including one or more processing cores, and a power supply 509. It will be understood by those skilled in the art that the structure of the electronic device 10 shown in Figure 11 does not constitute a limitation on the electronic device 10, and may include more or fewer components than shown, or combine certain components, or arrange the components differently.

[0111] The radio frequency circuit 501 can be used to send and receive information, or receive and send signals during a call. In particular, after receiving downlink information from the base station, it is handed over to one or more processors 508 for processing; in addition, uplink data is sent to the base station. Generally, the radio frequency circuit 501 includes but is not limited to an antenna, at least one amplifier, a tuner, one or more oscillators, a subscriber identity module (SIM) card, a transceiver, a coupler, a low noise amplifier (LNA), a duplexer, etc. In addition, the radio frequency circuit 501 can also communicate with the network and other devices through wireless communication. The wireless communication can use any communication standard or protocol, including but not limited to Global System of Mobile Communications (GSM), General Packet Radio Service (GPRS), Code Division Multiple Access (CDMA), Wideband Code Division Multiple Access (WCDMA), Long Term Evolution (LTE), email, Short Messaging Service (SMS), etc.

[0112] The memory 502 can be used to store applications and data. The applications stored in the memory 502 include executable code. The applications can be composed of various functional modules. The processor 508 executes various functional applications and data processing by running the applications stored in the memory 502. The memory 502 may mainly include a program storage area and a data storage area, wherein the program storage area may store an operating system, applications required for at least one function (such as a sound playback function, an image playback function, etc.), etc.; the data storage area may store data created based on the use of the electronic device 10 (such as audio data, a phone book, etc.), etc. In addition, the memory 502 may include a high-speed random access memory, and may also include a non-volatile memory, such as at least one disk storage device, a flash memory device, or other volatile solid-state storage device. Accordingly, the memory 502 may also include a memory controller to provide the processor 508 and the input unit 503 with access to the memory 502.

[0113] The input unit 503 can be used to receive input digital, character information or user feature information (such as fingerprints), and generate keyboard, mouse, joystick, optical or trackball signal input related to user settings and function control. Specifically, in a specific embodiment, the input unit 503 may include a touch-sensitive surface and other input devices. The touch-sensitive surface, also known as a touch display or touchpad, can collect user touch operations on or near it (such as operations performed by the user using a finger, stylus or any other suitable object or accessory on or near the touch-sensitive surface) and drive the corresponding connection device according to a pre-set program. Optionally, the touch-sensitive surface may include two parts: a touch detection device and a touch controller. The touch detection device detects the user's touch direction and detects the signal generated by the touch operation, and transmits the signal to the touch controller; the touch controller receives the touch information from the touch detection device, converts it into touch point coordinates, and then sends it to the processor 508. It can also receive commands sent by the processor 508 and execute them.

[0114] The display unit 504 can be used to display information input by the user or information provided to the user, as well as various graphical user interfaces of the electronic device 10. These graphical user interfaces can be composed of graphics, text, icons, videos, and any combination thereof. The display unit 504 may include a display panel. Optionally, the display panel can be configured in the form of a liquid crystal display (LCD), an organic light-emitting diode (OLED), or the like. Furthermore, a touch-sensitive surface can cover the display panel. When the touch-sensitive surface detects a touch operation on or near it, it transmits the information to the processor 508 to determine the type of touch event. The processor 508 then provides a corresponding visual output on the display panel based on the type of touch event. Although in Figure 11, the touch-sensitive surface and the display panel are implemented as two independent components to implement input and output functions, in some embodiments, the touch-sensitive surface and the display panel can be integrated to implement input and output functions. It is understood that the display screen 110 can include an input unit 503 and a display unit 504.

[0115] The electronic device 10 may also include at least one sensor 505, such as a light sensor, a motion sensor, and other sensors. Specifically, the light sensor may include an ambient light sensor and a proximity sensor, wherein the ambient light sensor may adjust the brightness of the display panel according to the brightness of the ambient light, and the proximity sensor may turn off the display panel and / or backlight when the electronic device 10 is moved to the ear. As a type of motion sensor, the gravity acceleration sensor can detect the magnitude of acceleration in all directions (generally three axes), and can detect the magnitude and direction of gravity when stationary. It can be used for applications that recognize the posture of the mobile phone (such as horizontal and vertical screen switching, related games, magnetometer posture calibration), vibration recognition related functions (such as pedometer, tapping), etc.; as for other sensors that the electronic device 10 can also be configured with, such as gyroscopes, barometers, hygrometers, thermometers, infrared sensors, etc., they will not be described in detail here.

[0116] The audio circuit 506 can provide an audio interface between the user and the electronic device 10 via a speaker and microphone. The audio circuit 506 can convert received audio data into electrical signals, transmit them to the speaker, and then convert them into sound signals for output. The microphone, on the other hand, converts collected sound signals into electrical signals, which are received by the audio circuit 506 and converted into audio data. The audio data is then processed by the processor 508 and then transmitted to, for example, another electronic device 10 via the RF circuit 501. Alternatively, the audio data can be output to the memory 502 for further processing. The audio circuit 506 may also include an earphone jack to provide communication between an external earphone and the electronic device 10.

[0117] Wireless Fidelity (WiFi) is a short-range wireless transmission technology. Electronic device 10, through WiFi module 507, can help users send and receive emails, browse web pages, and access streaming media, providing users with wireless broadband Internet access. Although FIG11 shows WiFi module 507, it is understood that it is not a required component of electronic device 10 and can be omitted as needed without changing the essence of the invention.

[0118] The processor 508 is the control center of the electronic device 10. It connects the various components of the electronic device 10 using various interfaces and circuits. By running or executing applications stored in the memory 502 and accessing data stored in the memory 502, it performs various functions of the electronic device 10 and processes data, thereby providing overall monitoring of the electronic device 10. Optionally, the processor 508 may include one or more processing cores. Preferably, the processor 508 may integrate an application processor and a modem processor, wherein the application processor primarily processes the operating system, user interface, and application programs, while the modem processor primarily handles wireless communications. It is understood that the modem processor may not be integrated into the processor 508.

[0119] The electronic device 10 also includes a power supply 509 for supplying power to various components. Preferably, the power supply 509 can be logically connected to the processor 508 via a power management system, thereby enabling the power management system to manage charging, discharging, and power consumption. The power supply 509 can also include one or more DC or AC power supplies, a recharging system, a power failure detection circuit, a power converter or inverter, a power status indicator, and other arbitrary components.

[0120] Although not shown in FIG11 , the electronic device 10 may further include a Bluetooth module, etc., which will not be described in detail here. In specific implementations, the above modules may be implemented as independent entities or in any combination as the same or multiple entities. The specific implementation of the above modules can be found in the previous method embodiments and will not be described in detail here.

[0121] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0122] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, and these modifications and improvements fall within the scope of protection of the present application. Therefore, the scope of protection of the present patent application shall be determined by the appended claims.

Claims

1. An optical system, characterized in that: The number of lenses with refractive power in the optical system is three or four, and the optical system includes, in order from the object side to the image side along the optical axis: A first lens having positive refractive power, wherein both the object side surface and the image side surface of the first lens are convex surfaces at the near optical axis; a second lens having refractive power; and a third lens having a refractive power, wherein one of the second lens and the third lens has a positive refractive power, and the other has a negative refractive power; The optical system satisfies the following conditional formula: 0.25≤f1 / f≤0.85; 0.15≤|f2 / f|≤0.45; 0.15≤|f3 / f|≤1.25; Wherein, f1 is the focal length of the first lens, f2 is the focal length of the second lens, and f3 is the focal length of the third lens.

2. The optical system according to claim 1, characterized in that The optical system further includes a fourth lens disposed on the image side of the third lens, wherein the fourth lens has positive refractive power.

3. The optical system according to claim 2, characterized in that One of the object-side surface and the image-side surface of the fourth lens is a convex surface at the near optical axis, and the other is a concave surface at the near optical axis.

4. The optical system according to any one of claims 1 to 3, characterized in that: When the second lens has positive refractive power, the object side surface and the image side surface of the second lens are both convex surfaces at the near optical axis; when the second lens has negative refractive power, the object side surface and the image side surface of the second lens are both concave surfaces at the near optical axis; when the third lens has negative refractive power, the object side surface and the image side surface of the third lens are both concave surfaces at the near optical axis; when the third lens has positive refractive power, the object side surface of the third lens is convex at the near optical axis.

5. The optical system according to any one of claims 1 to 3, characterized in that: The optical system satisfies the following conditional formula: 0.9≤f4 / f≤1.2; Wherein, f4 is the focal length of the fourth lens.

6. The optical system according to any one of claims 1 to 3, characterized in that: The optical system satisfies the following condition: 0.145mm -1 ≤FNO / f≤0.195mm -1 ; Wherein, FNO is the aperture number of the optical system.

7. The optical system according to any one of claims 1 to 3, characterized in that: The optical system satisfies the following conditional formula: 1.3≤TTL / f≤1.5; Wherein, TTL is the distance from the object side surface of the first lens to the imaging surface of the optical system on the optical axis.

8. A shooting module, characterized in that: An optical system comprising an image sensor, an optical transmission element and any one of claims 1 to 7; The optical transmission element has a light-transmitting surface, and the light-transmitting surface is provided with a light entrance area and a light exit area. The light entrance area is opposite to the optical system, and the light exit area is opposite to the image sensor. The optical transmission element is used for emitting at least part of the light incident on the light entrance area from the light exit area after at least two reflections, and the photosensitive surface of the image sensor is perpendicular to the axis of the optical system.

9. The shooting module according to claim 8, characterized in that: The optical transmission element also includes a first reflection surface and a second reflection surface, both of which are inclined to the light-transmitting surface. The optical transmission element is used to transmit the light incident from the light incident area through the first reflection surface, the light-transmitting surface, and the second reflection surface in sequence, and then emit it from the light exiting area.

10. The shooting module according to claim 9, characterized in that: The shooting module satisfies the following condition: 0.82≤E1 / H≤1.6; Wherein, E1 is the distance between the boundary between the first reflecting surface and the second reflecting surface, or the boundary between the extended surfaces of the first reflecting surface and the second reflecting surface and the light-transmitting surface in the axial direction of the optical system, and H is the axial size of the optical system.

11. The shooting module according to claim 9, characterized in that: The optical transmission element further includes a bottom surface, the bottom surface is opposite to the light-transmitting surface and connects the first reflective surface and the second reflective surface, and the camera module satisfies the following conditional formula: 0.7≤E2 / E1≤0.95; Among them, E2 is the distance between the bottom surface and the light-transmitting surface in the axial direction of the optical system, and E1 is the distance between the boundary between the first reflecting surface and the second reflecting surface, or the boundary between the first reflecting surface and the extended surface of the reflecting surface and the light-transmitting surface in the axial direction of the optical system.

12. The shooting module according to claim 9, characterized in that: The shooting module satisfies the following condition: 0.4mm / °≤C / α1≤0.5mm / °; Wherein, C is the thickness of the optical transmission element equivalent to a flat glass, and α1 is the angle between the light-transmitting surface and the first reflecting surface.

13. The shooting module according to claim 9, characterized in that: The shooting module satisfies the following condition: 3≤α2 / α1≤4.1; Wherein, α2 is the angle between the first reflecting surface and the second reflecting surface, and α1 is the angle between the light-transmitting surface and the first reflecting surface.

14. An electronic device, characterized in that: Comprising a shooting module as described in any one of claims 8-13.

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