Optical imaging system, imaging module and electronic device

Abstract

The present invention provides an optical imaging system, an imaging module, and an electronic device. The optical imaging system sequentially includes, along the optical axis from the object side to the image side: a prism; a first lens having refractive power, the object side surface of the first lens being convex near the optical axis; a second lens having refractive power; a third lens having refractive power; a fourth lens having refractive power, the image side surface of the fourth lens being convex near the optical axis; a fifth lens having refractive power; a sixth lens having refractive power; and the optical imaging system satisfies the following conditional formula: 1.7 < CT / TTL * 10 < 3, where CT is the total air gap sum on the optical axis from the image side surface of the first lens to the object side surface of the sixth lens, and TTL is the distance on the optical axis from the object side surface of the first lens to the imaging surface of the optical imaging system. The total length of the above optical imaging system has more space, enabling the realization of the requirement of thinning, and furthermore, by reasonably distributing the refractive power, the telephoto characteristics can be achieved, obtaining good optical performance.

Description

Technical Field

[0001] The present invention relates to optical imaging technology, and in particular to an optical imaging system, an imaging module and an electronic device. Background Art

[0002] In recent years, with the improvement of people's living standards and the continuous development of science and technology, portable electronic products such as smartphones have been updated at a faster pace, and the camera lenses installed on them have become more and more diversified to meet the needs of consumers, such as wide-angle lenses, telephoto lenses, TOF lenses, etc.

[0003] In the process of realizing this application, the inventors found that there are at least the following problems in the prior art: Due to the trend of electronic products becoming thinner and lighter, existing electronic products are usually equipped with ultra-thin lenses with shorter focal lengths, but the imaging effect is not good when shooting distant scenes, and telephoto lenses are generally long in size, which makes it difficult to install them on thin and light electronic devices. Therefore, how to realize a telephoto lens with good imaging quality and that can meet the requirements of thinness and lightness is a problem that needs to be solved urgently. Summary of the invention

[0004] In view of the above, it is necessary to propose an optical imaging system, an imaging module and an electronic device to solve the above problems.

[0005] The embodiment of the present application provides an optical imaging system, which includes, from the object side to the image side, along the optical axis:

[0006] A prism, wherein the prism comprises an incident surface, a reflecting surface and an exiting surface;

[0007] A first lens having refractive power, wherein the object side surface of the first lens is a convex surface at a near optical axis;

[0008] a second lens having refractive power;

[0009] a third lens having refractive power;

[0010] a fourth lens having refractive power, wherein the image side surface of the fourth lens is a convex surface at the near optical axis;

[0011] a fifth lens having refractive power;

[0012] a sixth lens having a refractive power;

[0013] The optical imaging system satisfies the following conditional formula:

[0014] 1.7 <CT / TTL*10<3;

[0015] Wherein, CT is the sum of the air gaps on the optical axis from the image side surface of the first lens to the object side surface of the sixth lens, and TTL is the distance on the optical axis from the object side surface of the first lens to the imaging surface of the optical imaging system.

[0016] The above-mentioned optical imaging system deflects the light transmission path in the optical imaging system by adding a reflective prism, so that the light no longer propagates in a straight line, so as to convert the system volume originally accumulated on the longitudinal axis to the horizontal axis, so that the total length of the optical imaging system has more space, which can meet the demand for lightweight and thinness. In addition, the refractive force is reasonably distributed, the gap between each lens is compressed to make it more compact, and the design of the lens barrel structure is simpler. At the same time, the total length of the optical imaging system will not be excessively increased while ensuring the telephoto characteristics, and the imaging quality can also be effectively guaranteed.

[0017] In some embodiments, an aperture is further included, and the aperture is arranged on the object side of the first lens. The refractive power of the first lens is positive, the refractive power of the second lens is positive, the refractive power of the third lens is negative, the refractive power of the fourth lens is positive, the object side of the fifth lens is concave at the near optical axis, and the image side is convex at the near optical axis, and the refractive power of the sixth lens is negative, and its image side is concave at the near optical axis.

[0018] In this way, by rationally configuring the refractive power and the surface shape of each lens, the overall size of the optical imaging system can be effectively reduced to meet the characteristics of miniaturization.

[0019] In some embodiments, the optical imaging system satisfies the following condition:

[0020] f*ImgH / 10≥1.75mm 2 ;

[0021] Wherein, f is the effective focal length of the optical imaging system, and ImgH is half of the image height corresponding to the maximum field of view angle of the optical imaging system.

[0022] In this way, the number of pixels can be increased by increasing the size of the chip to ensure the resolution of the telephoto lens. If it is lower than the lower limit, it becomes difficult to increase the pixels. At the same time, the focal length is too short, which is not conducive to the shooting experience of the telephoto lens when the background is blurred.

[0023] In some embodiments, the optical imaging system satisfies the following condition:

[0024] 0.8mm -1 <tanω / P*100<3mm -1 ;

[0025] Wherein, ω is half of the maximum field of view of the optical imaging system, the prism includes an incident surface, a reflection surface and an exit surface, the prism is cut into an isosceles right triangle by a surface that is perpendicular to both the incident surface and the reflection surface, and p is the length of the hypotenuse of the isosceles right triangle.

[0026] In this way, the size of the field of view angle can be controlled within a small range, making it easier for light to reach the lens from the reflective surface of the prism, and less likely to have harmful light paths such as total reflection. If it is higher than the upper limit, the prism size is too small, and light leakage is prone to occur. If it is lower than the lower limit, the prism size is too large, resulting in the entire module being large, which does not conform to the trend of thinness and lightness.

[0027] In some embodiments, the optical imaging system satisfies the following condition:

[0028] 7 <D / f*100<14;

[0029] Wherein, D is the distance from the exit surface of the prism to the object side of the first lens on the optical axis, and f is the effective focal length of the optical imaging system.

[0030] In this way, by controlling the distance between the exit surface of the prism and the object side surface of the first lens on the optical axis, the divergence angle of the light beam at the prism can be controlled, so that the optical imaging system has a higher imaging quality, and the difficulty of assembling the prism and the lens can be reduced. If it is higher than the upper limit, the distance is too large, the light diverges widely, the diameter of the lens increases, and the overall lens is large. If it is lower than the lower limit, the space is small and the difficulty of assembly increases.

[0031] In some embodiments, the optical imaging system satisfies the following condition:

[0032] 0.22<(R7+R8) / (R7-R8)<3.3;

[0033] Wherein, R7 is the curvature radius of the object side surface of the fourth lens at the optical axis, and R8 is the curvature radius of the image side surface of the fourth lens at the optical axis.

[0034] In this way, the fourth lens can provide a part of positive refractive power, and the image side surface of the fourth lens is convex at the optical axis. The curvature radii of the object side surface and the image side surface of the fourth lens at the optical axis are reasonably optimized, which can reduce the air gap between the image side surface of the third lens and the object side surface of the fourth lens, make the arrangement between the lenses more compact, and at the same time avoid excessive curvature of the fifth lens and the sixth lens.

[0035] In some embodiments, the optical imaging system satisfies the following condition:

[0036] f12 / f>0.49;

[0037] Wherein, f12 is the combined focal length of the first lens and the second lens, and f is the effective focal length of the optical imaging system.

[0038] In this way, the first lens and the second lens are positive lenses, which can jointly provide positive refractive power for the optical imaging system. The combined focal length of the first lens and the second lens can be reasonably controlled to be not less than the lower limit, so that the refractive power of the first lens and the second lens will not be too large, thereby ensuring that the entire optical imaging system has a longer focal length value to achieve a blurred background shooting experience.

[0039] In some embodiments, the optical imaging system satisfies the following condition:

[0040] -4 <f4 / R8<-0.9;

[0041] Wherein, f4 is the focal length of the fourth lens, and R8 is the radius of curvature of the image side surface of the fourth lens at the optical axis.

[0042] In this way, the image side surface of the fourth lens is convex near the optical axis, and is curved in the same direction as the object side surface of the fifth lens, satisfying the above relationship. The optical imaging system has a better ability to balance chromatic aberration and distortion.

[0043] In some embodiments, the optical imaging system satisfies the following condition:

[0044] 0.15 <v3 / (v1+v2)<0.24;

[0045] Wherein, v1 is the Abbe number of the first lens, v2 is the Abbe number of the second lens, and v3 is the Abbe number of the third lens.

[0046] In this way, the first lens and the second lens are positive lenses, which can provide positive refractive power and control the focal length of the entire optical imaging system. The third lens is a negative lens, and a smaller Abbe number is configured for the third lens to correct spherical aberration, which can improve the resolution. If it is higher than the upper limit, the ability of the third lens to correct aberration is insufficient, the modulation transfer function of the optical imaging system decreases, and the resolution is reduced. If it is lower than the lower limit, the material cost is too high, which is not conducive to actual production.

[0047] In some embodiments, the optical imaging system satisfies the following condition:

[0048] 0.8 <R9 / R10<1.3;

[0049] Wherein, R10 is the curvature radius of the object side surface of the fifth lens at the optical axis, and R11 is the curvature radius of the image side surface of the fifth lens at the optical axis.

[0050] In this way, by optimizing the curvature radius of the fifth lens element, the shapes of the object side surface and the image side surface can be made similar, and the curvature of the shapes is small, thereby reducing the sensitivity of optical performance.

[0051] The embodiment of the present application further proposes an imaging module, including:

[0052] Optical imaging systems; and

[0053] A photosensitive element is arranged on the image side of the optical imaging system.

[0054] The imaging module of the embodiment of the present invention includes an optical imaging system, which deflects the light transmission path in the optical imaging system by adding a reflective prism, so that the light no longer propagates in a straight line, so as to convert the system volume originally accumulated on the longitudinal axis into a lateral axis, so that the total length of the optical imaging system has more space, which can meet the demand for lightweight and thinness. In addition, the refractive force is reasonably distributed, the gap between each lens is compressed to make it more compact, and the design of the lens barrel structure is simpler. At the same time, the total length of the optical imaging system will not be excessively increased while ensuring the telephoto characteristics, and the imaging quality can also be effectively guaranteed.

[0055] An embodiment of the present invention provides an electronic device, comprising: a housing and an imaging module according to the above embodiment, wherein the imaging module is mounted on the housing.

[0056] The electronic device of the embodiment of the present invention includes an imaging module. The optical imaging system in the imaging module deflects the light transmission path in the optical imaging system by adding a reflective prism, so that the light no longer propagates in a straight line, so as to convert the system volume originally accumulated on the longitudinal axis to the lateral axis, so that the total length of the optical imaging system has more space, which can meet the demand for lightweight and thinness. In addition, the refractive force is reasonably distributed, the gap between each lens is compressed to make it more compact, and the design of the lens barrel structure is simpler. At the same time, the total length of the optical imaging system will not be excessively increased while ensuring the telephoto characteristics, and the imaging quality can also be effectively guaranteed. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] The above and / or additional aspects and advantages of the present invention may become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0058] Figure 1 Schematic diagram of the structure of the optical imaging system according to the first embodiment of the present invention.

[0059] Figure 2 4 is a graph showing spherical aberration, astigmatism and distortion of the optical imaging system in the first embodiment of the present invention.

[0060] Figure 3 Schematic diagram of the structure of an optical imaging system according to a second embodiment of the present invention.

[0061] Figure 4 4 is a graph showing spherical aberration, astigmatism and distortion of the optical imaging system in the second embodiment of the present invention.

[0062] Figure 5 Schematic diagram of the structure of an optical imaging system according to the third embodiment of the present invention.

[0063] Figure 6 3 is a graph showing spherical aberration, astigmatism and distortion of the optical imaging system in the third embodiment of the present invention.

[0064] Figure 7 4 is a schematic structural diagram of an optical imaging system according to a fourth embodiment of the present invention.

[0065] Figure 8 4 is a graph showing spherical aberration, astigmatism and distortion of the optical imaging system in the fourth embodiment of the present invention.

[0066] Fig. 9 4 is a schematic structural diagram of an optical imaging system according to a fifth embodiment of the present invention.

[0067] Fig.10 It is a graph showing spherical aberration, astigmatism and distortion of the optical imaging system in the fifth embodiment of the present invention.

[0068] Fig.11 It is a structural schematic diagram of an imaging module according to an embodiment of the present invention.

[0069] Fig.12 Schematic diagram of the structure of an electronic device according to an embodiment of the present invention.

[0070] Main component symbols

[0071] Electronic device 200

[0072] Image acquisition module 100

[0073] Optical imaging system 10

[0074] First lens L1

[0075] Second lens L2

[0076] The third lens L3

[0077] The fourth lens L4

[0078] Fifth lens L5

[0079] Sixth lens L6

[0080] Infrared filter L7

[0081] Aperture STO

[0082] Incident surface S1

[0083] Reflective surface S2

[0084] Exit surface S3

[0085] Object side S5, S7, S9, S11, S13, S15, S17

[0086] Like the side S6, S8, S10, S12, S14, S16, S18

[0087] Imaging surface S19

[0088] Photosensitive element 20

[0089] Housing 210 DETAILED DESCRIPTION

[0090] In order to make the purpose, technical scheme and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0091] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", clockwise", "counterclockwise" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are used only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0092] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or mutual communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0093] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0094] The disclosure below provides many different embodiments or examples to realize different structures of the present invention. In order to simplify the disclosure of the present invention, the parts and settings of specific examples are described below. Of course, they are only examples, and the purpose is not to limit the present invention. In addition, the present invention can repeat reference numbers and / or reference letters in different examples, and this repetition is for the purpose of simplicity and clarity, which itself does not indicate the relationship between the various embodiments and / or settings discussed. In addition, the present invention provides various specific examples of processes and materials, but those of ordinary skill in the art can be aware of the application of other processes and / or the use of other materials.

[0095] See also Figure 1 The optical imaging system 10 of the embodiment of the present invention includes, from the object side to the image side along the optical axis, an isosceles right-angle prism L0, a first lens L1 with positive refractive power, a second lens L2 with refractive power, a third lens L3 with refractive power, a fourth lens L4 with refractive power, a fifth lens L5 with refractive power, and a sixth lens L6 with refractive power.

[0096] The first lens L1 has an incident surface S1, a reflecting surface S2 and an exit surface S3. The first lens L1 has an object-side surface S5 and an image-side surface S6. The object-side surface S5 of the first lens L1 is a convex surface at the near optical axis. The second lens L2 has an object-side surface S7 and an image-side surface S8. The third lens L3 has an object-side surface S9 and an image-side surface S10. The fourth lens L4 has an object-side surface S11 and an image-side surface S12. The object-side surface S11 of the fourth lens L4 is a convex surface at the near optical axis. The fifth lens L5 has an object-side surface S13 and an image-side surface S14. The sixth lens L6 has an object-side surface S15 and an image-side surface S16.

[0097] The optical imaging system 10 satisfies the following relationship:

[0098] 1.7 <CT / TTL*10<3;

[0099] Wherein, CT is the sum of air gaps on the optical axis from the image-side surface S6 of the first lens L1 to the object-side surface S15 of the sixth lens L6, and TTL is the distance on the optical axis from the object-side surface S6 of the first lens L1 to the imaging surface S19 of the optical imaging system 10.

[0100] The above optical imaging system 10 deflects the light transmission path in the optical imaging system 10 by adding a reflective prism, so that the light no longer propagates in a straight line, so as to convert the system volume originally accumulated on the longitudinal axis into the horizontal direction, so that the total length of the optical imaging system 10 has more space, which can meet the demand for lightness and thinness, and reasonably distribute the refractive force, compress the gap between each lens, make it more compact, and also make the design of the lens barrel structure more simple. At the same time, the total length of the optical imaging system 10 will not be excessively increased while ensuring the telephoto characteristics, and the imaging quality can also be effectively guaranteed. If it is lower than the lower limit, the optical imaging system 10 is over-compressed, the light is deflected too much at a small air gap, the degree of freedom is reduced, and it is not conducive to the telephoto characteristics; if it is higher than the upper limit, the lenses are not compact enough, the total length is too long, and the actual assembly and production are difficult.

[0101] When imaging, the light incident from the outside is incident on the incident surface S1 of the isosceles right prism L0 along the optical axis LA, is bent and redirected by the reflection surface S2, and then is emitted from the exit surface S3 and passes through the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5 and the sixth lens L6 in sequence along the optical axis to reach the imaging surface S19.

[0102] In some embodiments, the optical imaging system 10 further includes a stop STO, which is disposed on the object side S5 of the first lens L1, the refractive power of the first lens L1 is positive, the refractive power of the second lens L2 is positive, the refractive power of the third lens L3 is negative, the refractive power of the fourth lens L4 is positive, the object side S13 of the fifth lens L5 is concave at the near optical axis, and the image side S14 is convex at the near optical axis, the refractive power of the sixth lens L6 is negative, and its image side S16 is concave at the near optical axis.

[0103] In this way, by reasonably configuring the refractive power and the surface shape of each lens, the overall size of the optical imaging system 10 can be effectively reduced to meet the characteristics of miniaturization.

[0104] In some embodiments, the optical imaging system 10 further includes an infrared filter L7, and the infrared filter L7 has an object-side surface S17 and an image-side surface S18. The infrared filter L7 is disposed on the image side of the sixth lens L6, and the infrared filter L7 is used to filter the imaging light, specifically to isolate the infrared light, to prevent the infrared light from being received by the photosensitive element, thereby preventing the infrared light from affecting the color and clarity of the normal image, thereby improving the imaging quality of the optical imaging system 10. Preferably, the infrared filter L7 is an infrared cutoff filter.

[0105] In some embodiments, the optical imaging system 10 satisfies the following conditional formula:

[0106] f*ImgH / 10≥1.75mm 2 ;

[0107] Wherein, f is the effective focal length of the optical imaging system, and ImgH is half of the image height corresponding to the maximum field of view of the optical imaging system.

[0108] In this way, the number of pixels can be increased by increasing the size of the chip to ensure the resolution of the telephoto lens. If it is lower than the lower limit, it becomes difficult to increase the pixels. At the same time, the focal length is too short, which is not conducive to the shooting experience of the telephoto lens when the background is blurred.

[0109] In some embodiments, the optical imaging system 10 satisfies the following conditional formula:

[0110] 0.8mm -1 <tanω / P*100<3mm -1 ;

[0111] Wherein, ω is half of the maximum field of view of the optical imaging system 10, the isosceles right prism L0 is cut into an isosceles right triangle by the surface which is perpendicular to both the incident surface S1 and the reflecting surface S2, and p is the length of the hypotenuse of the isosceles right triangle.

[0112] In this way, the size of the field of view angle can be controlled within a small range, making it easier for light to reach the lens from the reflective surface of the prism, and less likely to have harmful light paths such as total reflection. If it is higher than the upper limit, the prism size is too small, and light leakage is prone to occur. If it is lower than the lower limit, the prism size is too large, resulting in the entire module being large, which does not conform to the trend of thinness and lightness.

[0113] In some embodiments, the optical imaging system 10 satisfies the following conditional formula:

[0114] 7 <D / f*100<14;

[0115] Wherein, D is the distance from the exit surface S3 of the isosceles right prism L0 to the object side surface S5 of the first lens L1 on the optical axis, and f is the effective focal length of the optical imaging system 10 .

[0116] In this way, by controlling the distance between the exit surface S3 of the isosceles right prism L0 and the object side surface S5 of the first lens L1 on the optical axis, the divergence angle of the light beam at the prism can be controlled, so that the optical imaging system 10 has a higher imaging quality, and the difficulty of assembling the prism and the lens can be reduced. If it is higher than the upper limit, the distance is too large, the light diverges widely, the diameter of the lens increases, and the overall lens is large-scaled. If it is lower than the lower limit, the space is small and the difficulty of assembly increases.

[0117] In some embodiments, the optical imaging system 10 satisfies the following conditional formula:

[0118] 0.22<(R7+R8) / (R7-R8)<3.3;

[0119] Wherein, R7 is the curvature radius of the object-side surface S11 of the fourth lens L4 at the optical axis, and R8 is the curvature radius of the image-side surface S12 of the fourth lens L4 at the optical axis.

[0120] In this way, the fourth lens L4 can provide a part of positive refractive power, and the image-side surface S12 of the fourth lens L4 is convex at the optical axis. The curvature radii of the object-side surface S11 and the image-side surface S12 of the fourth lens L4 at the optical axis are reasonably optimized, so that the air gap between the image-side surface S9 of the third lens L3 and the object-side surface S11 of the fourth lens S10 can be reduced, so that the arrangement between the lenses is more compact, and at the same time, excessive curvature of the fifth lens L5 and the sixth lens L6 can be avoided.

[0121] In some embodiments, the optical imaging system 10 satisfies the following conditional formula:

[0122] f12 / f>0.49;

[0123] Wherein, f12 is the combined focal length of the first lens L1 and the second lens L2, and f is the effective focal length of the optical imaging system 10.

[0124] In this way, the first lens L1 and the second lens L2 are positive lenses, which can jointly provide positive refractive power for the optical imaging system 10. The combined focal length of the first lens L1 and the second lens L2 can be reasonably controlled to be not less than the lower limit, so that the refractive power of the first lens L1 and the second lens L2 will not be too large, thereby ensuring that the entire optical imaging system 10 has a longer focal length value to achieve a blurred background shooting experience.

[0125] In some embodiments, the optical imaging system 10 satisfies the following conditional formula:

[0126] -4 <f4 / R8<-0.9;

[0127] Wherein, f4 is the focal length of the fourth lens L4, and R8 is the radius of curvature of the image-side surface S12 of the fourth lens L4 at the optical axis.

[0128] Thus, the image-side surface S12 of the fourth lens L4 is convex near the optical axis and is curved in the same direction as the object-side surface S13 of the fifth lens L5, satisfying the above relationship. The optical imaging system 10 has better ability to balance chromatic aberration and distortion.

[0129] In some embodiments, the optical imaging system 10 satisfies the following conditional formula:

[0130] 0.15 <v3 / (v1+v2)<0.24;

[0131] Wherein, v1 is the Abbe number of the first lens L1, v2 is the Abbe number of the second lens L3, and v3 is the Abbe number of the third lens L3.

[0132] In this way, the first lens L1 and the second lens L2 are positive lenses, which can provide positive refractive power and control the focal length of the entire optical imaging system 10. The third lens L3 is a negative lens, and a smaller Abbe number is configured for the third lens L3 to correct spherical aberration, which can improve the resolution. If it is higher than the upper limit, the ability of the third lens L3 to correct aberration is insufficient, the modulation transfer function of the optical imaging system 10 decreases, and the resolution is reduced. If it is lower than the lower limit, the material cost is too high, which is not conducive to actual production.

[0133] In some embodiments, the optical imaging system 10 satisfies the following conditional formula:

[0134] 0.8 <R9 / R10<1.3;

[0135] Wherein, R10 is the curvature radius of the object-side surface S13 of the fifth lens L5 at the optical axis, and R11 is the curvature radius of the image-side surface S14 of the fifth lens L5 at the optical axis.

[0136] In this way, by optimizing the curvature radius of the fifth lens L5, the shapes of the object side surface and the image side surface can be made similar, and the curvature of the shapes is smaller, thereby reducing the sensitivity of optical performance.

[0137] In some embodiments, the object-side surfaces and the image-side surfaces of the first lens L1 to the sixth lens L6 are all aspherical surfaces.

[0138] The shape of the aspheric surface is determined by the following formula:

[0139]

[0140] Among them, Z is the longitudinal distance from any point on the aspheric surface to the surface vertex, r is the distance from any point on the aspheric surface to the optical axis, c is the vertex curvature (the inverse of the radius of curvature), k is the cone constant, and Ai is the correction coefficient of the i-th order aspheric surface.

[0141] First embodiment

[0142] Please refer to Figure 1 The optical imaging system 10 of the first embodiment includes, from the object side to the image side along the optical axis, an isosceles right-angle prism L0, an aperture 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, a fifth lens L5 with negative refractive power, a sixth lens L6 with negative refractive power, and an infrared filter L7.

[0143] Among them, the object side surface S5 of the first lens L1 is convex at the near optical axis, and the image side surface S6 is concave at the near optical axis; the object side surface S7 of the second lens L2 is convex at the near optical axis, and the image side surface S8 is concave at the near optical axis; the object side surface S9 of the third lens L3 is concave at the near optical axis, and the image side surface S10 is concave at the near optical axis; the object side surface S11 of the fourth lens L4 is convex at the near optical axis, and the image side surface S12 is convex at the near optical axis; the object side surface S13 of the fifth lens L5 is concave at the near optical axis, and the image side surface S14 is convex at the near optical axis; the object side surface S15 of the sixth lens L6 is concave at the near optical axis, and the image side surface S16 is concave at the near optical axis.

[0144] The object-side surface S5 of the first lens L1 is convex at the near circumference, and the image-side surface S6 is concave at the near circumference; the object-side surface S7 of the second lens L2 is convex at the near circumference, and the image-side surface S8 is concave at the near circumference; the object-side surface S9 of the third lens L3 is concave at the near circumference, and the image-side surface S10 is concave at the near circumference; the object-side surface S11 of the fourth lens L4 is convex at the near circumference, and the image-side surface S12 is convex at the near circumference; the object-side surface S13 of the fifth lens L5 is concave at the near circumference, and the image-side surface S14 is convex at the near circumference; the object-side surface S15 of the sixth lens L6 is concave at the near circumference, and the image-side surface S16 is convex at the near circumference.

[0145] The reference wavelengths of the focal length, refractive index and Abbe number in the first embodiment are all 587.5617 nm, and the optical imaging system 10 in the first embodiment meets the conditions in the following table.

[0146] Table 1

[0147]

[0148] It should be noted that, in Table 1, f is the focal length of the optical imaging system 10, FNO is the aperture number of the optical imaging system 10, FOV is the maximum field angle of the optical imaging system 10, TTL is the distance from the object side of the first lens to the imaging surface of the optical imaging system on the optical axis, and the Y radius is the curvature radius of each surface at the optical axis.

[0149] Table 2

[0150]

[0151]

[0152] Figure 2 The longitudinal spherical aberration curve, astigmatism curve and distortion curve of the optical imaging system 10 of the first embodiment are shown, wherein the longitudinal spherical aberration curve represents the deviation of the focal point of light of different wavelengths after passing through each lens of the optical imaging system 10; the astigmatism curve represents the meridional image curvature and the sagittal image curvature; and the distortion curve represents the distortion magnitude value corresponding to different field angles. Figure 2 It can be seen that the optical imaging system 10 provided in the first embodiment can achieve good imaging quality.

[0153] Second embodiment

[0154] Please refer to Figure 3 The optical imaging system 10 of the second embodiment includes, from the object side to the image side along the optical axis, an isosceles right-angle prism L0, an aperture 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, a fifth lens L5 with negative refractive power, a sixth lens L6 with negative refractive power, and an infrared filter L7.

[0155] Among them, the object side surface S5 of the first lens L1 is convex at the near optical axis, and the image side surface S6 is concave at the near optical axis; the object side surface S7 of the second lens L2 is convex at the near optical axis, and the image side surface S8 is concave at the near optical axis; the object side surface S9 of the third lens L3 is convex at the near optical axis, and the image side surface S10 is concave at the near optical axis; the object side surface S11 of the fourth lens L4 is convex at the near optical axis, and the image side surface S12 is convex at the near optical axis; the object side surface S13 of the fifth lens L5 is concave at the near optical axis, and the image side surface S14 is convex at the near optical axis; the object side surface S15 of the sixth lens L6 is concave at the near optical axis, and the image side surface S16 is concave at the near optical axis.

[0156] The object-side surface S5 of the first lens L1 is convex at the near circumference, and the image-side surface S6 is concave at the near circumference; the object-side surface S7 of the second lens L2 is convex at the near circumference, and the image-side surface S8 is concave at the near circumference; the object-side surface S9 of the third lens L3 is convex at the near circumference, and the image-side surface S10 is concave at the near circumference; the object-side surface S11 of the fourth lens L4 is convex at the near circumference, and the image-side surface S12 is convex at the near circumference; the object-side surface S13 of the fifth lens L5 is concave at the near circumference, and the image-side surface S14 is convex at the near circumference; the object-side surface S15 of the sixth lens L6 is concave at the near circumference, and the image-side surface S16 is convex at the near circumference.

[0157] The reference wavelengths of the focal length, refractive index and Abbe number in the second embodiment are all 587.5618 nm, and the optical imaging system 10 in the second embodiment meets the conditions in the following table.

[0158] Table 3

[0159]

[0160] It should be noted that, in Table 3, f is the focal length of the optical imaging system 10, FNO is the aperture number of the optical imaging system 10, FOV is the maximum field angle of the optical imaging system 10, TTL is the distance from the object side of the first lens to the imaging surface of the optical imaging system on the optical axis, and the Y radius is the curvature radius of each surface at the optical axis.

[0161] Table 4

[0162]

[0163]

[0164] Figure 4The longitudinal spherical aberration curve, astigmatism curve and distortion curve of the optical imaging system 10 of the second embodiment are shown, wherein the longitudinal spherical aberration curve represents the deviation of the convergence point of light of different wavelengths after passing through each lens of the optical imaging system 10; the astigmatism curve represents the meridional image curvature and the sagittal image curvature; and the distortion curve represents the distortion magnitude value corresponding to different field angles. Figure 4 It can be seen that the optical imaging system 10 provided in the second embodiment can achieve good imaging quality.

[0165] Third embodiment

[0166] Please refer to Figure 5 The optical imaging system 10 of the third embodiment includes, from the object side to the image side along the optical axis, an isosceles right-angle prism L0, an aperture 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, a fifth lens L5 with positive refractive power, a sixth lens L6 with negative refractive power, and an infrared filter L7.

[0167] Among them, the object side surface S5 of the first lens L1 is convex at the near optical axis, and the image side surface S6 is concave at the near optical axis; the object side surface S7 of the second lens L2 is convex at the near optical axis, and the image side surface S8 is concave at the near optical axis; the object side surface S9 of the third lens L3 is convex at the near optical axis, and the image side surface S10 is concave at the near optical axis; the object side surface S11 of the fourth lens L4 is convex at the near optical axis, and the image side surface S12 is convex at the near optical axis; the object side surface S13 of the fifth lens L5 is concave at the near optical axis, and the image side surface S14 is convex at the near optical axis; the object side surface S15 of the sixth lens L6 is concave at the near optical axis, and the image side surface S16 is concave at the near optical axis.

[0168] The object-side surface S5 of the first lens L1 is convex at the near circumference, and the image-side surface S6 is concave at the near circumference; the object-side surface S7 of the second lens L2 is convex at the near circumference, and the image-side surface S8 is concave at the near circumference; the object-side surface S9 of the third lens L3 is convex at the near circumference, and the image-side surface S10 is concave at the near circumference; the object-side surface S11 of the fourth lens L4 is convex at the near circumference, and the image-side surface S12 is convex at the near circumference; the object-side surface S13 of the fifth lens L5 is concave at the near circumference, and the image-side surface S14 is convex at the near circumference; the object-side surface S15 of the sixth lens L6 is concave at the near circumference, and the image-side surface S16 is convex at the near circumference.

[0169] The reference wavelengths of the focal length, refractive index and Abbe number in the third embodiment are all 587.5618 nm, and the optical imaging system 10 in the third embodiment meets the conditions in the following table.

[0170] Table 5

[0171]

[0172]

[0173] It should be noted that, in Table 5, f is the focal length of the optical imaging system 10, FNO is the aperture number of the optical imaging system 10, FOV is the maximum field angle of the optical imaging system 10, TTL is the distance from the object side of the first lens to the imaging surface of the optical imaging system on the optical axis, and the Y radius is the curvature radius of each surface at the optical axis.

[0174] Table 6

[0175]

[0176]

[0177] Figure 6 The longitudinal spherical aberration curve, astigmatism curve and distortion curve of the optical imaging system 10 of the third embodiment are shown, wherein the longitudinal spherical aberration curve represents the deviation of the convergence point of light of different wavelengths after passing through each lens of the optical imaging system 10; the astigmatism curve represents the meridional image curvature and the sagittal image curvature; and the distortion curve represents the distortion magnitude value corresponding to different field angles. Figure 6 It can be seen that the optical imaging system 10 provided in the third embodiment can achieve good imaging quality.

[0178] Fourth embodiment

[0179] Please refer to Figure 7 The optical imaging system 10 of the fourth embodiment includes, from the object side to the image side along the optical axis, an isosceles right-angle prism L0, an aperture 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, a fifth lens L5 with negative refractive power, a sixth lens L6 with negative refractive power, and an infrared filter L7.

[0180] Among them, the object side surface S5 of the first lens L1 is convex at the near optical axis, and the image side surface S6 is concave at the near optical axis; the object side surface S7 of the second lens L2 is convex at the near optical axis, and the image side surface S8 is concave at the near optical axis; the object side surface S9 of the third lens L3 is convex at the near optical axis, and the image side surface S10 is concave at the near optical axis; the object side surface S11 of the fourth lens L4 is concave at the near optical axis, and the image side surface S12 is convex at the near optical axis; the object side surface S13 of the fifth lens L5 is concave at the near optical axis, and the image side surface S14 is convex at the near optical axis; the object side surface S15 of the sixth lens L6 is convex at the near optical axis, and the image side surface S16 is concave at the near optical axis.

[0181] The object-side surface S5 of the first lens L1 is convex at the near circumference, and the image-side surface S6 is concave at the near circumference; the object-side surface S7 of the second lens L2 is convex at the near circumference, and the image-side surface S8 is concave at the near circumference; the object-side surface S9 of the third lens L3 is convex at the near circumference, and the image-side surface S10 is concave at the near circumference; the object-side surface S11 of the fourth lens L4 is convex at the near circumference, and the image-side surface S12 is convex at the near circumference; the object-side surface S13 of the fifth lens L5 is concave at the near circumference, and the image-side surface S14 is convex at the near circumference; the object-side surface S15 of the sixth lens L6 is concave at the near circumference, and the image-side surface S16 is convex at the near circumference.

[0182] The reference wavelengths of the focal length, refractive index and Abbe number in the fourth embodiment are all 587.5618 nm, and the optical imaging system 10 in the fourth embodiment meets the conditions in the following table.

[0183] Table 7

[0184]

[0185]

[0186] It should be noted that, in Table 7, f is the focal length of the optical imaging system 10, FNO is the aperture number of the optical imaging system 10, FOV is the maximum field angle of the optical imaging system 10, TTL is the distance from the object side of the first lens to the imaging surface of the optical imaging system on the optical axis, and the Y radius is the curvature radius of each surface at the optical axis.

[0187] Table 8

[0188]

[0189] Figure 8 The longitudinal spherical aberration curve, astigmatism curve and distortion curve of the optical imaging system 10 of the fourth embodiment are shown, wherein the longitudinal spherical aberration curve represents the deviation of the convergence point of light of different wavelengths after passing through each lens of the optical imaging system 10; the astigmatism curve represents the meridional image curvature and the sagittal image curvature; and the distortion curve represents the distortion magnitude value corresponding to different field angles. Figure 8 It can be seen that the optical imaging system 10 provided in the fourth embodiment can achieve good imaging quality.

[0190] Fifth embodiment

[0191] Please refer to Fig. 9The optical imaging system 10 of the fifth embodiment includes, from the object side to the image side along the optical axis, an isosceles right-angle prism L0, an aperture 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, a fifth lens L5 with positive refractive power, a sixth lens L6 with negative refractive power, and an infrared filter L7.

[0192] Among them, the object side surface S5 of the first lens L1 is convex at the near optical axis, and the image side surface S6 is concave at the near optical axis; the object side surface S7 of the second lens L2 is convex at the near optical axis, and the image side surface S8 is concave at the near optical axis; the object side surface S9 of the third lens L3 is convex at the near optical axis, and the image side surface S10 is concave at the near optical axis; the object side surface S11 of the fourth lens L4 is concave at the near optical axis, and the image side surface S12 is convex at the near optical axis; the object side surface S13 of the fifth lens L5 is concave at the near optical axis, and the image side surface S14 is convex at the near optical axis; the object side surface S15 of the sixth lens L6 is concave at the near optical axis, and the image side surface S16 is concave at the near optical axis.

[0193] The object-side surface S5 of the first lens L1 is convex at the near circumference, and the image-side surface S6 is concave at the near circumference; the object-side surface S7 of the second lens L2 is convex at the near circumference, and the image-side surface S8 is concave at the near circumference; the object-side surface S9 of the third lens L3 is convex at the near circumference, and the image-side surface S10 is concave at the near circumference; the object-side surface S11 of the fourth lens L4 is concave at the near circumference, and the image-side surface S12 is convex at the near circumference; the object-side surface S13 of the fifth lens L5 is concave at the near circumference, and the image-side surface S14 is convex at the near circumference; the object-side surface S15 of the sixth lens L6 is concave at the near circumference, and the image-side surface S16 is convex at the near circumference.

[0194] The reference wavelengths of the focal length, refractive index and Abbe number in the fifth embodiment are all 587.5618 nm, and the optical imaging system 10 in the fifth embodiment meets the conditions in the following table.

[0195] Table 9

[0196]

[0197]

[0198] It should be noted that, in Table 9, f is the focal length of the optical imaging system 10, FNO is the aperture number of the optical imaging system 10, FOV is the maximum field angle of the optical imaging system 10, TTL is the distance from the object side of the first lens to the imaging surface of the optical imaging system on the optical axis, and the Y radius is the curvature radius of each surface at the optical axis.

[0199] Table 10

[0200]

[0201] Fig.10 The longitudinal spherical aberration curve, astigmatism curve, and distortion curve of the optical imaging system 10 of the fifth embodiment are shown, where the longitudinal spherical aberration curve represents the deviation of the convergence points of light rays of different wavelengths after passing through each lens of the optical imaging system 10; the astigmatism curve represents the curvature of the meridional image plane and the sagittal image plane; the distortion curve represents the distortion magnitude values corresponding to different field angles. According to Fig.10 it can be seen that the optical imaging system 10 given in the fifth embodiment can achieve good imaging quality.

[0202] Table 11 shows the values of CT / TTL*10, f*ImgH / 10, 0.8 < tanω / P*100, D / f*100, (R7 + R8) / (R7 - R8), f12 / f, f4 / R8, v3 / (v1 + v2), and R9 / R10 in the optical imaging systems 10 of the first to fifth embodiments.

[0203] Table 11

[0204]

[0205] Please refer to Fig.11 , the image pickup module 100 of the embodiment of the present invention includes an optical imaging system 10 and a photosensitive element 20, and the photosensitive element 20 is disposed on the image side of the optical imaging system 10.

[0206] Specifically, the photosensitive element 20 can adopt a complementary metal oxide semiconductor (CMOS) image sensor or a charge-coupled device (CCD).

[0207] In the optical imaging system 10 of the image pickup module 100 of the embodiment of the present invention, the light transmission path in the optical imaging system is deflected by adding a reflection prism, so that the light no longer propagates in a straight line, converting the system volume originally stacked on the vertical axis into a horizontal direction, providing more space for the total length of the optical imaging system, meeting the requirement of thinning. Moreover, by reasonably distributing the bending force and compressing the gaps between the lenses to make it more compact, the design of the lens barrel structure becomes simpler. At the same time, while ensuring the telephoto characteristics, the total length of the optical imaging system will not increase excessively, and the imaging quality can be effectively guaranteed. If it is lower than the lower limit, the optical imaging system is overly compressed, the deflection angle of the light is too large in a small air gap, the degree of freedom decreases, which is not conducive to the telephoto characteristics; if it is higher than the upper limit, the lenses are not compact enough, the total length is too long, and the actual assembly and production are difficult.

[0208] Please continue to refer to Fig.12 The electronic device 200 of the embodiment of the present invention includes a housing 210 and an imaging module 100 , and the imaging module 100 is installed on the housing 210 for acquiring images.

[0209] The electronic device 200 of the embodiment of the present invention includes, but is not limited to, miniaturized smart phones, mobile phones and PDAs (Personal Digital Assistants), game consoles, PCs, smart phones, car-mounted cameras, surveillance cameras, tablet computers, laptop computers, e-book readers, portable multimedia players (PMPs), portable phones, video phones, digital still cameras, mobile medical devices, wearable devices, and other electronic devices that support imaging.

[0210] The optical imaging system 10 in the electronic device 1000 of the above embodiment deflects the light transmission path in the optical imaging system by adding a reflective prism, so that the light no longer propagates in a straight line, so as to convert the system volume originally accumulated on the longitudinal axis into the horizontal direction, so that the total length of the optical imaging system has more space, which can meet the demand for lightness and thinness, and reasonably distribute the refractive force, compress the gap between each lens, make it more compact, and also make the design of the lens barrel structure more simple. At the same time, the total length of the optical imaging system will not be excessively increased while ensuring the telephoto characteristics, and the imaging quality can also be effectively guaranteed. If it is lower than the lower limit, the optical imaging system is over-compressed, the light is deflected too much at a small air gap, the degree of freedom is reduced, and it is not conducive to the telephoto characteristics; if it is higher than the upper limit, the lenses are not compact enough, the total length is too long, and the actual assembly and production are difficult.

[0211] It is obvious to those skilled in the art that the present application is not limited to the details of the exemplary embodiments described above, and that the present application can be implemented in other specific forms without departing from the spirit or essential features of the present application. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive, and the scope of the present application is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present application.

[0212] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present application and are not intended to limit it. Although the present application has been described in detail with reference to the preferred embodiments, a person of ordinary skill in the art should understand that the technical solution of the present application may be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the present application.

Claims

1. An optical imaging system, characterized in that: From the object side to the image side along the optical axis, it includes: A prism, wherein the prism comprises an incident surface, a reflecting surface and an exiting surface; A first lens having positive refractive power, wherein the object side surface of the first lens is convex at the near optical axis; a second lens having positive refractive power; A third lens element having negative refractive power; a fourth lens element having positive refractive power, wherein the image side surface of the fourth lens element is a convex surface at the near optical axis; a fifth lens having a refractive power, wherein the object side surface of the fifth lens is a concave surface at the near optical axis, and the image side surface of the fifth lens is a convex surface at the near optical axis; a sixth lens having negative refractive power, wherein the image side surface of the sixth lens is a concave surface at the near optical axis, and the image side surface of the sixth lens is an aspherical surface; The optical imaging system further comprises an aperture, which is arranged on the object side of the first lens; The optical imaging system satisfies the following conditional formula: 1.7 <CT / TTL*10<3 Wherein, CT is the sum of the air gaps on the optical axis from the image side surface of the first lens to the object side surface of the sixth lens, and TTL is the distance on the optical axis from the object side surface of the first lens to the imaging surface of the optical imaging system.

2. The optical imaging system according to claim 1, wherein: The optical imaging system satisfies the following conditional formula: f*ImgH / 10≥1.75mm 2 ; Wherein, f is the effective focal length of the optical imaging system, and ImgH is half of the image height corresponding to the maximum field of view angle of the optical imaging system.

3. The optical imaging system according to claim 1, wherein: The optical imaging system satisfies the following conditional formula: 0.8 mm -1 <tanω / P*100<3mm -1 ; Wherein, ω is half of the maximum field of view of the optical imaging system, the prism is cut into an isosceles right triangle by a surface that is perpendicular to both the incident surface and the reflective surface, and p is the length of the hypotenuse of the isosceles right triangle.

4. The optical imaging system according to claim 1, wherein: The optical imaging system satisfies the following conditional formula: 7 <D / f*100<14; Wherein, D is the distance from the exit surface of the prism to the object side of the first lens on the optical axis, and f is the effective focal length of the optical imaging system.

5. The optical imaging system according to claim 1, wherein: The optical imaging system satisfies the following conditional formula: 0.22<(R7+R8) / (R7-R8)<3.3; Wherein, R7 is the curvature radius of the object side surface of the fourth lens at the optical axis, and R8 is the curvature radius of the image side surface of the fourth lens at the optical axis.

6. The optical imaging system according to claim 1, wherein: The optical imaging system satisfies the following conditional formula: f12 / f>0.49; Wherein, f12 is the combined focal length of the first lens and the second lens, and f is the effective focal length of the optical imaging system.

7. The optical imaging system according to claim 1, wherein: The optical imaging system satisfies the following conditional formula: -4 <f4 / R8<-0.9; Wherein, f4 is the focal length of the fourth lens, and R8 is the radius of curvature of the image side surface of the fourth lens at the optical axis.

8. The optical imaging system according to claim 1, wherein: The optical imaging system satisfies the following conditional formula: 0.15 <v3 / (v1+v2)<0.24; Wherein, v1 is the Abbe number of the first lens, v2 is the Abbe number of the second lens, and v3 is the Abbe number of the third lens.

9. The optical imaging system according to claim 1, wherein: The optical imaging system satisfies the following conditional formula: 0.8 <R9 / R10<1.3; Wherein, R10 is the curvature radius of the object side surface of the fifth lens at the optical axis, and R11 is the curvature radius of the image side surface of the fifth lens at the optical axis.

10. An imaging module, comprising: The optical imaging system according to any one of claims 1 to 9; and A photosensitive element is arranged on the image side of the optical imaging system.

11. An electronic device comprising: case; and The imaging module described in claim 10 is mounted on the housing.

Images