Periscopic lens

Abstract

The invention relates to a periscopic lens, which comprises a lens barrel, a prism, a lens group and a spacing element group, the lens barrel is provided with an object side end face and an image side end face, the prism is arranged on the object side of the lens barrel and is used for reflecting light, and the lens group comprises first to sixth lenses which are sequentially arranged from the object side end face to the image side end face and are arranged on the same optical axis. The focal power of the second to third lenses is positive, negative and negative in sequence, and the spacing element group comprises first to fifth spacing elements corresponding to the image sides of the first to fifth lenses in sequence. Based on the structure of the periscopic lens barrel, the third to fifth lenses and the third to fifth spacer elements satisfy the relational expression: 0.33 < = (T34 + T45) / L < = 0.37; 0.10 < = (d4m-d3s) / d3mlt; 0.85, 0.29 lt, 0.28 lt; (d5s-d3m) / d4slt; therefore, the requirements of lens miniaturization and picture stray light reduction can be met.

Description

Technical Field

[0001] The present invention relates to the technical field of periscope lenses, and in particular to a periscope lens. Background Art

[0002] With the development of high-performance, high-quality, and ultra-thin mobile phones, higher requirements are also placed on mobile phone camera technology. The proportion of telephoto lenses used in mobile phone cameras is also increasing, and the demand for zoom multiples and aperture of telephoto lenses is also increasing. At the same time, to meet the demand for small size, prisms are used more and more widely. However, under the current size conditions of lenses with prisms, while ensuring the amount of light required for imaging, the light can easily reach the edge area of ​​the lens after reflection. This part of the light will be abnormally reflected in the edge area of ​​the lens and produce stray light. In order to solve this kind of stray light problem, a common technical solution is to proportionally expand the size of the lens to keep the light away from the edge of the lens. However, this is contrary to the development direction of miniaturization of lenses, and the cost of the product is also high. Summary of the invention

[0003] Since existing periscope telephoto lenses are limited by product size, resulting in serious stray light problems in actual use, it is necessary to provide a periscope lens.

[0004] A periscope lens, comprising: A lens barrel having an object side end surface and an image side end surface; A lens group is mounted on the lens barrel, wherein the lens group includes a first lens, a second lens with positive optical power, a third lens with negative optical power, a fourth lens with negative optical power, a fifth lens and a sixth lens which are arranged in sequence from the object side end surface to the image side end surface and arranged on the same optical axis; a spacer element group mounted on the lens barrel, the spacer element group comprising a first spacer element disposed on the image side of the first lens and abutting against the image side surface of the first lens, a second spacer element disposed on the image side of the second lens and abutting against the image side surface of the second lens, a third spacer element disposed on the image side of the third lens and abutting against the image side surface of the third lens, a fourth spacer element disposed on the image side of the fourth lens and abutting against the image side surface of the fourth lens, and a fifth spacer element disposed on the image side of the fifth lens and abutting against the image side surface of the fifth lens; and a prism, disposed on the object side of the lens barrel and having a reflective surface, wherein the reflective surface is arranged obliquely to the optical axis of the lens group and an angle between a normal line of the reflective surface and the optical axis of the lens group is an acute angle; The air gap T34 between the third lens and the fourth lens on the optical axis, the air gap T45 between the fourth lens and the fifth lens on the optical axis, the object side inner diameter d3s of the third spacer element, the image side inner diameter d3m of the third spacer element, the object side inner diameter d4s of the fourth spacer element, the image side inner diameter d4m of the fourth spacer element, and the object side inner diameter d5s of the fifth spacer element satisfy the following conditions: 0.33≤(T34+T45) / L≤0.37; 0.10≤(d4m-d3s) / d3m<0.85; and 0.29<(d5s-d3m) / d4s<0.6.

[0005] With such arrangement, firstly, the integrated structure of the prism replaces the existing lens group for realizing the reflection and convergence functions, which is conducive to promoting the miniaturization of the lens; secondly, by controlling the ratio of the air gap between the third lens, the fourth lens and the fifth lens on the optical axis to the total length of the lens within a reasonable range, the trend of the light in the lens can be effectively guaranteed, and the utilization rate of the light can be improved; but since the air gaps between the third, fourth and fifth lenses are too large, it is easier for the light to reach the edge of the lens after passing through these three lenses, especially for the fourth lens located in the middle, the stray light generated before and after the light is refracted by the fourth lens is more, by controlling the inner diameters of the third spacing element and the fourth spacing element, under the premise of not blocking the effective light, the internal reflected stray light generated in the fourth lens and the stray light refracted on the inner side surface of the spacing element can be reduced as much as possible, thereby reducing the adverse effect of the stray light on the picture.

[0006] In one embodiment, the prism further has an incident surface and an exit surface located on both sides of the reflective surface, the incident surface and the exit surface are both spherical surfaces, the incident surface is convex, and the exit surface is concave, and the axial distance Y from the intersection of the incident surface and the optical axis to the image side surface of the sixth lens satisfies: 23.90 mm <Y<24.15mm。

[0007] In one embodiment, the maximum height L of the lens barrel and the effective focal length f of the periscope lens satisfy the following conditions: 0.35 <L / f<0.51。

[0008] In one embodiment, the air gap T34 between the third lens and the fourth lens on the optical axis, the air gap T45 between the fourth lens and the fifth lens on the optical axis, the maximum thickness CP3 of the third spacing element, and the maximum thickness CP4 of the fourth spacing element satisfy the following: 1.30<(T34+T45) / (CP3+CP4)<4.75.

[0009] In one embodiment, the positive and negative properties of the optical power of the first lens and the optical power of the sixth lens are the same, and the positive and negative properties of the optical power of the fifth lens and the optical power of the sixth lens are different; The effective focal length f5 of the fifth lens, the object side inner diameter d5s of the fifth spacing element, and the object side inner diameter d4s of the fourth lens satisfy: 4.5<|f5 / (d5s-d4s)|<11.85, preferably 4.5<|f5 / (d5s-d4s)|<7.05.

[0010] In one embodiment, the effective focal length f3 of the third lens, the air gap T34 between the third lens and the fourth lens on the optical axis, and the object side inner diameter d3s of the third spacing element satisfy: -2.15 mm -1 <f3 / T34 / d3s<-1.00mm -1 .

[0011] In one embodiment, the spacing distance EP12 between the first spacing element and the second spacing element along the optical axis, the spacing distance EP23 between the second spacing element and the third spacing element along the optical axis, and the center thickness CT2 of the second lens satisfy: 1.40<(EP12+EP23) / CT2<2.05.

[0012] In one embodiment, the sum of the maximum thicknesses ∑CP1 of all the spacing elements between the first lens and the second lens, the air gap T12 between the first lens and the second lens on the optical axis, the maximum thickness CP2 of the second spacing element, and the air gap T23 between the second lens and the third lens on the optical axis satisfy the following conditions: 5.55<∑CP1 / T12+CP2 / T23<12.15, preferably 5.55<∑CP1 / T12+CP2 / T23<7.00.

[0013] In one embodiment, the maximum thickness CP2 of the second spacer element, the spacing distance EP23 between the second spacer element and the third spacer element along the optical axis, and the center thickness CT3 of the third lens satisfy: 1.85<(CP2+EP23) / CT3<2.75.

[0014] In one embodiment, the object side inner diameter d0s of the lens barrel and the object side inner diameter d1s of the first spacing element satisfy the following relationship: 1.00 <d0s / d1s<1.41。

[0015] In one embodiment, the image side inner diameter d0m of the lens barrel and the image side outer diameter D5m of the fifth spacing element satisfy the following relationship: 1.05≤d0m / D5m≤1.10.

[0016] In one embodiment, the maximum thickness CP4 of the fourth spacer element, the spacing distance EP45 between the fourth spacer element and the fifth spacer element along the optical axis, and the effective focal length f5 of the fifth lens satisfy: -0.22≤(CP4+EP45) / f5≤0.20 and (CP4+EP45)≠0.

[0017] In one embodiment, the minimum aperture d0smin of the lens barrel on the object side and the inner diameter d3s of the third spacing element on the object side satisfy the following conditions: 0.85 <d0smin / d3s<1.30。 BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 A schematic diagram of the structure of a periscope lens in an embodiment provided in the present application; Figure 2 for Figure 1 Schematic diagram of the size markings of the middle lens barrel, lens group and spacer element group; Figure 3A It is a schematic diagram of the structure of the periscope lens in working condition 1-1; Figure 3B It is a schematic diagram of the structure of the periscope lens in working condition 1-2; Figure 3C It is a schematic diagram of the structure of the periscope lens in working condition 1-3; Figure 4A is a distortion curve diagram of the periscope lens in Example 1; Figure 4B is a magnification chromatic aberration curve diagram of the periscope lens in Example 1; Figure 5A It is a schematic diagram of the structure of the periscope lens in working condition 2-1; Figure 5B It is a schematic diagram of the structure of the periscope lens in working condition 2-2; Figure 5C This is a schematic diagram of the structure of the periscope lens in Works 2-3; Fig. 6A is a distortion curve diagram of the periscope lens in Example 2; Figure 6B is a magnification chromatic aberration curve diagram of the periscope lens in Example 2; Fig. 7A It is a schematic diagram of the structure of the periscope lens in working condition 3-1; Figure 7B It is a schematic diagram of the structure of the periscope lens in working condition 3-2; Figure 7C It is a schematic diagram of the structure of the periscope lens in working condition 3-3; Fig. 8Ais a distortion curve diagram of the periscope lens in Example 3; Figure 8B is a magnification chromatic aberration curve diagram of the periscope lens in Example 3; Fig. 9A The test spot diagram of a periscope lens when (T34+T45) / L=0.34, (d4m-d3s) / d3m=0.08, (d5s-d3m) / d4s=0.2; Fig. 9B The test spot diagram of a periscope lens when (T34+T45) / L=0.34, (d4m-d3s) / d3m=0.1, (d5s-d3m) / d4s=0.3; Fig. 9C The test spot diagram of a periscope lens when (T34+T45) / L=0.34, (d4m-d3s) / d3m=0.87, (d5s-d3m) / d4s=0.62.

[0019] Reference numerals: E1, first lens; E2, second lens; E3, third lens; E4, fourth lens; E5, fifth lens; E6, sixth lens; P0, lens barrel; P1, first spacing element; P1b, first auxiliary spacing element; P2, second spacing element; P3, third spacing element; P4, fourth spacing element; P5, fifth spacing element; P5b, fifth auxiliary spacing element. DETAILED DESCRIPTION

[0020] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present invention, so the present invention is not limited by the specific embodiments disclosed below.

[0021] 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", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0022] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0023] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0024] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0025] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used herein are for illustrative purposes only and are not intended to be the only implementation method.

[0026] With the development of high-performance, high-quality, and ultra-thin mobile phones, higher requirements are also placed on mobile phone camera technology. The proportion of telephoto lenses used in mobile phone cameras is also increasing, and the demand for zoom multiples and aperture of telephoto lenses is also increasing. At the same time, to meet the demand for small size, prisms are used more and more widely. However, under the current size conditions of lenses with prisms, while ensuring the amount of light required for imaging, the light can easily reach the edge area of ​​the lens after reflection. This part of the light will be abnormally reflected in the edge area of ​​the lens and produce stray light. In order to solve stray light problems such as reflected stray light in the lens, a common technical solution is to proportionally expand the size of the lens to keep the light away from the edge of the lens. However, this is contrary to the development direction of miniaturization of lenses, and the cost of the product is also high.

[0027] Based on this, it is necessary to provide a periscope lens that can reduce stray light while ensuring image quality.

[0028] See also Figure 1 , Figure 1 This is a schematic diagram of the structure of a periscope lens in an embodiment provided in the present application. Figure 2 for Figure 1Schematic diagram of the size markings of the lens barrel P0, the lens group and the spacer element group. The present application provides a periscope lens comprising a lens barrel P0, a prism P, a lens group mounted on the lens barrel P0 and a spacer element group mounted on the lens barrel P0, wherein the lens barrel P0 has an object side end face and an image side end face and the inner wall is stepped, the prism P is disposed on the object side of the lens barrel P0 and has a reflective surface, the reflective surface is inclined to the optical axis of the lens group and the angle between the normal of the reflective surface and the optical axis of the lens group is an acute angle, so as to achieve the transfer of the light path, in addition, the prism P can replace the existing lens group for realizing the reflection and convergence functions, which is conducive to promoting the miniaturization of the lens, the lens group comprises a first lens E1 arranged in sequence from the object side end face to the image side end face and arranged on the same optical axis, a second lens E2 having a positive optical power, a third lens E3 having a negative optical power, a fourth lens E4 having a negative optical power, a fifth lens E5 and a sixth lens E6, the spacer element group comprises a lens E1 disposed on the image side of the first lens E1 and abutting against the first lens E1 The first spacing element P1 on the image side of the third lens E3, the second spacing element P2 disposed on the image side of the second lens E2 and abutting the image side of the second lens E2, the third spacing element P3 disposed on the image side of the third lens E3 and abutting the image side of the third lens E3, the fourth spacing element P4 disposed on the image side of the fourth lens E4 and abutting the image side of the fourth lens E4, and the fifth spacing element P5 disposed on the image side of the fifth lens E5 and abutting the image side of the fifth lens E5. Based on the structure of the periscope lens, the air gap T34 on the optical axis between the third lens E3 and the fourth lens E4, the air gap T45 on the optical axis between the fourth lens E4 and the fifth lens E5, the object side inner diameter d3s of the third spacing element P3, the image side inner diameter d3m of the third spacing element P3, the object side inner diameter d4s of the fourth spacing element P4, the image side inner diameter d4m of the fourth spacing element P4, and the object side inner diameter d5s of the fifth spacing element P5 satisfy the following: 0.33≤(T34+T45) / L≤0.37; 0.10≤(d4m-d3s) / d3m<0.85; and 0.29<(d5s-d3m) / d4s<0.6.

[0029] Based on the constraints of the above three conditional expressions, by controlling the ratio of the air gap between the third lens E3, the fourth lens E4 and the fifth lens E5 on the optical axis to the total length of the lens within a reasonable range, the trend of the light in the lens can be effectively guaranteed and the utilization rate of the light can be improved; however, if the air gap between the third lens E3, the fourth lens E4 and the fifth lens is too large, the light is more likely to reach the edge of the lens after passing through these three lenses, especially for the fourth lens E4 located in the middle, the light will generate more stray light before and after being refracted by the fourth lens E4. By controlling the shapes of the third spacing element P3, the fourth spacing element P4 and the fifth spacing element P5 by conditional expressions 2 and 3, the internal reflected stray light generated in the fourth lens E4 and the stray light refracted on the inner side surface of the spacing element can be reduced as much as possible without blocking the effective light, thereby reducing the adverse effect of the stray light on the picture.

[0030] Specifically, Figures 9A to 9C As shown, Fig. 9A This is a schematic diagram of the light spot of the lens test when the conditions (T34+T45) / L=0.34, (d4m-d3s) / d3m=0.08, (d5s-d3m) / d4s=0.2 are met. Fig. 9B This is a schematic diagram of the light spot of the lens test when the conditions (T34+T45) / L=0.34, (d4m-d3s) / d3m=0.1, (d5s-d3m) / d4s=0.3 are met. Fig. 9C This is a schematic diagram of the light spot of the lens test when the conditional formula (T34+T45) / L=0.34, (d4m-d3s) / d3m=0.87, (d5s-d3m) / d4s=0.62 is met. By comparing the three light spot diagrams, we can see that Fig. 9A The spot area is larger and more diffuse. Fig. 9C The light spot energy is larger and more concentrated. Fig. 9B The test results of the representative lens are good, that is to say, controlling the values ​​of (T34+T45) / L, (d4m-d3s) / d3m and (d5s-d3m) / d4s within the conditional range provided in this application can significantly reduce the amount of stray light, thereby obtaining a better imaging effect. Fig. 9AThe reason for the generation of internal stray light is as follows: when the inner aperture of the third spacer element P3 is relatively large, and the inner diameters of the fourth spacer element P4 and the fifth spacer element P5 remain unchanged, the marginal rays refracted by the third lens E3 will be reflected when hitting the object side surface of the fourth lens E4 and return to the marginal structure area of the third lens E3. After multiple reflections on the inner surface of the marginal area of the third lens E3, they will exit from the image side of the third lens E3 and reach the photosensitive chip behind the lens together with the effective rays, thus generating internal reflection stray light. In other words, in this case, the stray light is formed within the marginal structure area of the third lens E3, and the third spacer element P3 cannot effectively block the formation and continuous transmission of this internal reflection stray light. The fourth spacer element P4 and the fifth spacer element P5 also cannot effectively block the continuous transmission of this internal reflection stray light, resulting in interference of this internal reflection stray light on the image. Fig. 9C The reason for the generation of stray light is as follows: the inner aperture of the third spacer element P3 is relatively small, the inner aperture of the fourth spacer element P4 is relatively small, and the inner aperture of the fifth spacer element P5 is relatively large. The marginal rays refracted by the third lens E3 and the fourth lens E4 hit the inner side surface of the fourth spacer element P4 and are reflected to form stray light. This part of the stray light will not be blocked by the fifth spacer element P5 and the subsequent spacer elements when further passing through the fifth lens E5, and thus reach the photosensitive chip behind the lens together with the effective rays and form an image, resulting in a decrease in image quality. In other words, in this case, the stray light is formed on the inner surface of the fourth spacer element P4, and the fifth spacer element P5 cannot effectively block the continuous transmission of this internal reflection stray light, resulting in interference of this stray light on the image. As Fig. 9B shown in, by controlling the inner diameters of the third spacer element P3, the fourth spacer element P4, and the fifth spacer element P5 within a reasonable range according to the conditional formula provided in this application, it is possible to ensure the effective rays required for imaging and also block the excess rays at the edges of the lens, thereby reducing the risk of lens stray light.

[0031] Optionally, in an embodiment provided in this application, the prism P further has an incident surface and an exit surface located on both sides of the reflection surface. Both the incident surface and the exit surface are spherical surfaces. The incident surface is a convex surface and the exit surface is a concave surface. The axial distance Y from the intersection point of the incident surface and the optical axis to the image side surface of the sixth lens E6 satisfies: 23.90 mm < Y < 24.15 mm. By providing the optical power prism P with a convex incident surface and a concave exit surface, the object-side light ray aperture can be effectively reduced without changing the system aperture size, thereby reducing the screen occupation ratio. Satisfying the conditional formula 23.90 mm < Y < 24.15 mm can better improve the performance while keeping the overall structure compact when the focal length is fixed.

[0032] Optionally, in an embodiment provided by the present application, the maximum height L of the lens barrel P0 and the effective focal length f of the periscope lens satisfy: 0.35 < L / f < 0.51. By restricting the above conditional formula, the length of the lens body can be controlled on the premise of ensuring performance parameters, thereby reducing the overall length and height of the module integration, and realizing the functions of being thin, light, and miniaturized.

[0033] Optionally, in an embodiment provided by the present application, the air gap T34 between the third lens E3 and the fourth lens E4 on the optical axis, the air gap T45 between the fourth lens E4 and the fifth lens E5 on the optical axis, the maximum thickness CP3 of the third spacer P3, and the maximum thickness CP4 of the fourth spacer P4 satisfy: 1.30 < (T34 + T45) / (CP3 + CP4) < 4.75. Based on the restriction of this conditional formula, by controlling the air gap between the third lens E3, the fourth lens E4, and the fifth lens E5 on the optical axis and the thickness of the spacer elements therebetween, the divergence angle and convergence ability of the marginal rays can be controlled, ensuring good imaging quality and marginal brightness; it can also ensure that the bending degrees of the third lens E3 and the fifth lens E5 are not too large, ensuring the processability of the lens, and at the same time can effectively control the stray light generated by the fourth lens E4, improving the clarity of the picture.

[0034] Optionally, in an embodiment provided by the present application, the positive and negative attributes of the optical power of the first lens E1 and the sixth lens E6 are the same, and the positive and negative attributes of the optical power of the fifth lens E5 and the sixth lens E6 are different; the effective focal length f5 of the fifth lens E5, the object-side inner diameter d5s of the fifth spacer P5, and the object-side inner diameter d4s of the fourth lens E4 satisfy: 4.5 < |f5 / (d5s - d4s)| < 11.85. Through the restriction of this conditional formula, the first lens E1 and the sixth lens E6 have the same positive and negative attributes of optical power, and the fifth lens E5 and the sixth lens E6 have different positive and negative attributes of optical power, which can ensure the balanced light path trend of the system, make the lens aperture differences not large, thereby improving the overall assembly performance; based on the conditional formula 4.5 < |f5 / (d5s - d4s)| < 11.85, by controlling the optical power of the fifth lens E5, the height of the tail-end light rays can be effectively controlled, and by controlling the object-side inner diameter of the fifth spacer P5, it is beneficial to improve the imaging quality at the edge and reduce stray light. The preferred range of this conditional formula is 4.5 < |f5 / (d5s - d4s)| < 7.05.

[0035] Optionally, in an embodiment provided by the present application, the effective focal length f3 of the third lens E3, the air gap T34 between the third lens E3 and the fourth lens E4 on the optical axis, and the object-side inner diameter d3s of the third spacer P3 satisfy: -2.15 mm -1 < f3 / T34 / d3s < -1.00 mm-1 By constraining the conditional expression, the effective focal length of the third lens E3 and the ratio of the air gap between the third lens E3 and the fourth lens E4 on the optical axis are controlled within a reasonable range, and the angle of light emission on the image side of the third lens E3 can be controlled to ensure that the bending angle of the image side of the third lens E3 is reasonable, and the processability of the lens is improved. At the same time, the inner diameter of the object side of the third spacing element P3 is controlled to control the formation of stray light of the third lens E3, reduce unnecessary light passing through, and improve the edge imaging quality.

[0036] Optionally, in an embodiment provided in the present application, the spacing distance EP12 between the first spacing element P1 and the second spacing element P2 along the optical axis, the spacing distance EP23 between the second spacing element P2 and the third spacing element P3 along the optical axis, and the center thickness CT2 of the second lens E2 satisfy: 1.40<(EP12+EP23) / CT2<2.05. Based on the constraint of this conditional expression, it is helpful to control the effective diameter difference between the first lens E1 and the second lens E2 and the thickness ratio of the second lens E2, ensure the molding process of the second lens E2, ensure the structural rationality of the two lenses, thereby improving the overall molding process and assembly stability of the lens, and improving the yield of the system.

[0037] Optionally, in an embodiment provided in the present application, the sum of the maximum thickness of all the spacer elements between the first lens E1 and the second lens E2 ∑CP1, the air gap T12 between the first lens E1 and the second lens E2 on the optical axis, the maximum thickness CP2 of the second spacer element P2, and the air gap T23 between the second lens E2 and the third lens E3 on the optical axis satisfy: 5.55<∑CP1 / T12+CP2 / T23<12.15. Based on the constraints of the above conditional expressions, the thickness of the side of the second lens E2 can be controlled within a suitable range to ensure the stability of lens molding; ensure that the deflection angle of the light before and after the second lens E2 is not too large, thereby reducing the sensitivity of the system; and at the same time, the thickness of the side of the third lens E3 can be indirectly controlled and the light can pass smoothly through the third lens E3, thereby ensuring the processability and thickness ratio of the two lens molds, thereby facilitating the surface stability of the two lenses after molding, and ultimately helping to improve the quality of the lens. Optionally, the present application further provides a first auxiliary spacer element P1b (with a maximum thickness of CP1b along the optical axis) between the first lens E1 and the second lens E2, with the two ends of the spacer element respectively contacting the image side surface of the first spacer element P1 and the object side surface of the second lens E2, so that the relative position of the second lens E2 can be further fixed, and the edge of the second lens E2 can be shielded to prevent stray light from being generated due to multiple reflections after the light enters the edge of the second lens E2. The preferred range of the conditional expression is 5.55<∑CP1 / T12+CP2 / T23<7.00.

[0038] Optionally, in an embodiment provided by the present application, the maximum thickness CP2 of the second spacer element P2, the spacing distance EP23 between the second spacer element P2 and the third spacer element P3 along the optical axis direction, and the central thickness CT3 of the third lens E3 satisfy: 1.85 < (CP2 + EP23) / CT3 < 2.75. Based on the constraint of the above conditional formula, the central thickness of the third lens E3 can be ensured to be within a reasonable range, the thickness ratio of the third lens E3 is constrained, the lens forming process is ensured, and at the same time, the edge thickness of the fourth lens E4 can be indirectly controlled and the light can pass through the fourth lens E4 smoothly, ensuring the processability and thickness ratio of the two lenses, thus being beneficial to the surface shape stability after the two lenses are formed, and ultimately contributing to the improvement of the lens quality.

[0039] Optionally, in an embodiment provided by the present application, the object-side inner diameter d0s of the lens barrel P0 and the object-side inner diameter d1s of the first spacer element P1 satisfy: 1.00 < d0s / d1s < 1.41. Based on the constraint of this conditional formula, controlling the object-side inner diameter of the lens barrel P0 can effectively ensure the aperture size of the lens, make the light input of the system sufficient, improve the overall light input of the optical system, so that this telephoto lens can also obtain good shooting clarity at night; at the same time, it can also constrain the formation of stray light, reduce the entry of excess light into the system, and improve the imaging quality.

[0040] Optionally, in an embodiment provided by the present application, the image-side inner diameter d0m of the lens barrel P0 and the image-side outer diameter D5m of the fifth spacer element P5 satisfy: 1.05 ≤ d0m / D5m ≤ 1.10. Through the constraint of this conditional formula, it is possible to avoid the excessive exit angle of the light after passing through the sixth lens E6, thereby reducing the stray light caused by the secondary reflection of the light on the image-side end face of the lens barrel P0, and at the same time constraining the outer dimension of the lens barrel P0 to ensure the miniaturization of the lens.

[0041] Optionally, in an embodiment provided by the present application, the maximum thickness CP4 of the fourth spacer element P4, the spacing distance EP45 between the fourth spacer element P4 and the fifth spacer element P5 along the optical axis direction, and the effective focal length f5 of the fifth lens E5 satisfy: -0.22 ≤ (CP4 + EP45) / f5 ≤ 0.20 and (CP4 + EP45) ≠ 0. By constraining the focal length of the fifth lens E5, the light height and light throughput of the system light entering the sixth lens E6 from the fifth lens E5 can be controlled, the effective diameter difference between the fifth lens E5 and the sixth lens E6 can be improved, the light height difference can be reasonably controlled, and combined with the constraint of the edge thickness of the fifth lens E5, the forming difficulty of the fifth lens E5 can be reduced and the assembly stability of the fifth lens E5 and the front and rear lenses can be improved, thus ensuring the overall structural stability.

[0042] Optionally, in an embodiment provided by the present application, the minimum aperture d0smin of the lens barrel P0 on the object side and the inner diameter d3s of the object side of the third spacer element P3 satisfy: 0.85 < d0smin / d3s < 1.30. Based on the constraint of this conditional formula, the trend of the light direction change when passing through the first lens E1, the second lens E2, and the third lens E3 can be made smoother, avoiding the situation of too large a light deflection angle in the optical system, which is beneficial to reducing the sensitivity of the optical system, improving the lens processability, and at the same time ensuring smooth light transition and system stability.

[0043] The present application also provides a periscope lens, including: A lens barrel P0, having an object-side end face and an image-side end face; A prism P, placed on the object side of the lens barrel P0 and having a reflecting surface for reflecting light towards the object-side end face; A lens group, mounted on the lens barrel P0, the lens group includes a first lens E1, a second lens E2 with positive optical power, a third lens E3 with negative optical power, a fourth lens E4 with negative optical power, a fifth lens E5, and a sixth lens E6 arranged in sequence from the object-side end face to the image-side end face and coaxially arranged; and A spacer element group, mounted on the lens barrel P0, the spacer element group includes a first spacer element P1 placed on the image side of the first lens E1 and abutting against the image side surface of the first lens E1, a second spacer element P2 placed on the image side of the second lens E2 and abutting against the image side surface of the second lens E2, a third spacer element P3 placed on the image side of the third lens E3 and abutting against the image side of the third lens E3, a fourth spacer element P4 placed on the image side of the fourth lens E4 and abutting against the image side of the fourth lens E4, a fifth spacer element P5 placed on the image side of the fifth lens E5 and abutting against the image side surface of the fifth lens E5; The maximum height L of the lens barrel P0, the effective focal length f of the periscope lens, the air gap T34 between the third lens E3 and the fourth lens E4 on the optical axis, the air gap T45 between the fourth lens E4 and the fifth lens E5 on the optical axis, the maximum thickness CP3 of the third spacer element P3, and the maximum thickness CP4 of the fourth spacer element P4 satisfy: 0.35 < L / f < 0.51; and 1.30 < (T34 + T45) / (CP3 + CP4) < 4.75.

[0044] The present invention achieves telephoto by arranging a prism and reasonably distributing the focal length of the lens to shorten the total length, further constrains the ratio of the maximum height of the lens group barrel to the effective focal length, controls the length of the entire lens while ensuring the effective focal length of the lens, thereby reducing the overall length and height after module integration. However, due to performance requirements, the air gap between some lenses is relatively large, which is not conducive to the support of the lens on the one hand, and on the other hand, the excessive thickness of the lens edge will affect the processability of the lens. By constraining the air gap between the third, fourth, and fifth lenses and the thickness of the spacing element, the divergence angle of the light at the edge of the lens can be controlled and the lens's ability to converge light can be improved, thereby ensuring better imaging quality and edge brightness. At the same time, the maximum thickness of the third and fourth spacing elements is reasonably set to ensure the overall curvature of the third, fourth, and fifth lenses to ensure the processability of the lens.

[0045] Some specific and non-restrictive examples of the present application are described in more detail below with reference to the accompanying drawings.It is to be understood that any one of the following examples one to three is applicable to all embodiments of the present application.In the three embodiments provided in the present application, each embodiment comprises three working conditions, and the parameters (surface type, radius of curvature, center thickness, material, cone coefficient, etc.) of the lens used for imaging in the three working conditions are the same, and the distance between the lenses is the same, and the difference is that the parameters (thickness, object side inner diameter, image side inner diameter, etc.) of the structure (lens barrel, spacing element) used for auxiliary imaging are different.

[0046] For the convenience of description, in the following examples, OBJ represents the object plane of the lens, STO represents the surface of the aperture, f represents the effective focal length of the periscope lens, fi represents the effective focal length of the i-th lens, i=1, 2, 3, 4, 5, 6, Semi-FOV represents half of the maximum field of view, and FNO is the aperture size of the periscope lens.

[0047] Also, please refer again to Figure 1 , the surface numbers of the functional surfaces that the light passes through along the reverse direction of the optical path are defined as S1 to SN in sequence, where S1 represents the surface number of the first functional surface that the light passes through along the reverse direction of the optical path, and SN represents the surface number of the Nth functional surface that the light passes through along the reverse direction of the optical path. Specifically, S1, S2, and S3 represent the incident surface, the reflecting surface, and the emitting surface of the prism P, respectively, S4 and S5 represent the object side surface and the image side surface of the first lens E1, respectively, S6 and S7 represent the object side surface and the image side surface of the second lens E2, respectively, S8 and S9 represent the object side surface and the image side surface of the third lens E3, respectively, S10 and S11 represent the object side surface and the image side surface of the fourth lens E4, respectively, S12 and S13 represent the object side surface and the image side surface of the fifth lens E5, respectively, and S14 and S15 represent the object side surface and the image side surface of the sixth lens E6, respectively.

[0048] The optical path is explained as follows: the light emitted by the object enters the prism from S1, is reflected by S2, and is emitted from S3. It passes through S4~S15 in sequence and reaches the photosensitive chip behind the lens.

[0049] The aspheric surface involved in this patent satisfies the following formula:

[0050] In the above formula, x represents the distance vector height from the position at a height of h along the optical axis to the vertex of the aspheric surface, c represents the curvature, h represents the radial distance from the optical axis, k represents the cone coefficient, and Ai represents the i-th order constant.

[0051] In the embodiments provided below, the concave-convex directions of the object side and image side of each lens are based on the lens itself. Figure 3A Taking the fourth lens E4 and the fifth lens E5 arranged in sequence from the object to the image as an example, if the surface concavo-convex type of the fourth lens E4 is object convex and image concave, it means that the object side surface of the fourth lens E4 gradually moves away from the fifth lens E5 from the edge to the center of the lens, and the image side surface of the fourth lens E4 gradually moves away from the fifth lens from the edge to the center of the lens.

[0052] See also Figure 2 , Figure 2 A schematic diagram of the dimensions of an optical imaging lens of the present application is shown. Figure 2 Parameters such as d1s, d3s, d3m, d4s, d4m, d5s, D5m, d0s, d0m, CP1, EP12, CP2, EP23, CP3, CP4, EP45, L, CP4, EP45, etc. are indicated in the figure to clearly and intuitively understand the meaning of the parameters. In order to facilitate the description of the optical imaging lens and the surface shape of the specific lens, these parameters will no longer be reflected in the drawings when describing the specific embodiments later.

[0053] Embodiment 1 like FIG. 3A to FIG. 3C As shown, this embodiment involves three working conditions 1-1, 1-2, and 1-3. Figure 3A It is a schematic diagram of the structure of the periscope lens in working condition 1-1. Figure 3B This is a schematic diagram of the structure of the periscope lens in working condition 1-2. Figure 3C The figure is a schematic diagram of the structure of the periscope lens in working condition 1-3. In working conditions 1-1, 1-2, and 1-3, the parameters of the lens used for imaging (surface shape, radius of curvature, thickness, material, and conic coefficient) are the same, while the parameters of the lens barrel and multiple spacer elements used for auxiliary imaging (maximum thickness, inner diameter, lens edge thickness) are at least partially different, see Table 8 for details.

[0054] Specifically, in this embodiment, the optical power and surface concavo-convex type of each lens in the lens group are as follows: the positive and negative properties of the optical power of the first lens E1 to the sixth lens E6 are: positive, positive, negative, negative, negative, positive, the first lens E1 has a convex object and a concave image, the second lens E2 has a convex object and a convex image, the third lens E3 has a convex object and a concave image, the fourth lens E4 has a convex object and a concave image, the fifth lens E5 has a concave object and a convex image, and the sixth lens E6 has a convex object and a convex image.

[0055] In this embodiment, except for the first spacer P1, the object side and image side of the other spacers in the spacer group are respectively abutted against two adjacent lenses. In this embodiment, the first spacer P1 and the first auxiliary spacer P1b are sequentially arranged between the first lens E1 and the second lens E2 from the object to the image, the object side and image side of the first spacer P1 are respectively abutted against the first lens E1 and the first auxiliary spacer P1b, and the image side surface of the first auxiliary spacer P1b is abutted against the object side surface of the second lens E2.

[0056] Table 1 shows the design data of the lens in the periscope lens in Example 1, and Table 2 shows the aspheric coefficients of twelve surfaces S4 to S15. In the table, S16 and S17 respectively represent the object side and image side of the filter, and S18 represents the receiving surface of the sensor.

[0057] Table 1

[0058] Table 2

[0059] After simulation test, the results are as follows Figure 4A and Figure 4B As shown, Figure 4A is a distortion curve diagram of the periscope lens in Example 1, Figure 4B : is a magnification chromatic aberration curve of the periscope lens in Example 1. FIG. 4A to FIG. 4B It can be seen that the periscope lens of Example 1 can achieve good imaging quality.

[0060] Embodiment 2 like FIG. 5A to FIG. 5C As shown, this embodiment involves three working conditions 2-1, 2-2, and 2-3. Figure 5A This is a schematic diagram of the structure of the periscope lens in working condition 2-1. Figure 5B This is a schematic diagram of the structure of the periscope lens in working condition 2-2. Figure 5C The figure is a schematic diagram of the structure of the periscope lens in working condition 2-3. In working conditions 2-1, 2-2, and 2-3, the parameters (surface shape, radius of curvature, thickness, material, and conic coefficient) of the lens used for imaging are the same, while the parameters of the lens barrel and multiple spacer elements used for auxiliary imaging are at least partially different, as shown in Table 8.

[0061] Specifically, in this embodiment, the optical power and surface concavo-convex type of each lens in the lens group are as follows: the positive and negative properties of the optical power of the first lens E1 to the sixth lens E6 are: positive, positive, negative, negative, negative, positive, the first lens E1 has a convex object and a concave image, the second lens E2 has a convex object and a convex image, the third lens E3 has a convex object and a concave image, the fourth lens E4 has a convex object and a concave image, the fifth lens E5 has a concave object and a convex image, and the sixth lens E6 has a convex object and a convex image. In this embodiment, except for the first spacing element P1 and the fifth spacing element P5, the object sides and image sides of the other spacing elements in the spacing element group are respectively abutted against two adjacent lenses. In this embodiment, the first spacing element P1 and the first auxiliary spacing element P1b are sequentially arranged between the first lens E1 and the second lens E2 from the object to the image, the object side and the image side of the first spacing element P1 are respectively abutted against the first lens E1 and the first auxiliary spacing element P1b, and the image side surface of the first auxiliary spacing element P1b is abutted against the object side surface of the second lens E2. The fifth spacing element P5 and the fifth auxiliary spacing element P5b are sequentially arranged between the fifth lens E5 and the sixth lens E6 from the object to the image, the object side and the image side of the fifth spacing element P5 are respectively abutted against the fifth lens E5 and the fifth auxiliary spacing element P5b, and the image side of the fifth auxiliary spacing element P5b is abutted against the object side surface of the sixth lens E6.

[0062] Table 3 shows the design data of the lens in the periscope lens in Example 2, and Table 4 shows the aspheric coefficients of twelve surfaces S4 to S15. In the table, S16 and S17 respectively represent the object side and image side of the filter placed on the image side of the lens barrel P0, and S18 represents the receiving surface of the sensor placed on the image side of the filter.

[0063] Table 3

[0064] Table 4

[0065] After simulation test, the results are as follows Fig. 6A and Figure 6B As shown, Fig. 6A is a distortion curve diagram of the periscope lens in Example 2, Figure 6B : is a magnification chromatic aberration curve of the periscope lens in Example 2. FIG. 6A to FIG. 6B It can be seen that the periscope lens of the second embodiment can achieve good imaging quality.

[0066] Embodiment 3 like 7A to 7C As shown, this embodiment involves three working conditions 3-1, 3-2, and 3-3. Fig. 7A This is a schematic diagram of the structure of the periscope lens in working condition 3-1. Figure 7B This is a schematic diagram of the structure of the periscope lens in working condition 3-2. Figure 7C The figure is a schematic diagram of the structure of the periscope lens in working condition 3-3. In working conditions 3-1, 3-2, and 3-3, the parameters (surface shape, radius of curvature, thickness, material, and conic coefficient) of the lens used for imaging are the same, while the parameters of the lens barrel and multiple spacer elements used for auxiliary imaging are at least partially different, as shown in Table 8.

[0067] Specifically, in this embodiment, the focal length and surface concavo-convex type of each lens in the lens group are as follows: the positive and negative properties of the focal lengths of the first lens E1 to the sixth lens E6 are: negative, positive, negative, negative, positive, negative, the first lens E1 has a convex object and a concave image, the second lens E2 has a convex object and a concave image, the third lens E3 has a convex object and a concave image, the fourth lens E4 has a concave object and a convex image, the fifth lens E5 has a convex object and a convex image, and the sixth lens E6 has a concave object and a concave image. In this embodiment, except for the first spacing element P1 in the spacing element group, the object side and the image side of the remaining spacing elements are respectively abutted against two adjacent lenses. In this embodiment, the first spacing element P1 and the first auxiliary spacing element P1b are arranged in sequence from the object to the image between the first lens E1 and the second lens E2, the object side and the image side of the first spacing element P1 are respectively abutted against the first lens E1 and the first auxiliary spacing element P1b, and the image side of the first auxiliary spacing element P1b is abutted against the object side of the second lens E2.

[0068] Table 5 shows the design data of the lens in the periscope lens in Example 3, and Table 6 shows the aspheric coefficients of twelve surfaces S4 to S15. In the table, S16 and S17 respectively represent the object side and image side of the filter placed on the image side of the lens barrel P0, and S18 represents the receiving surface of the sensor placed on the image side of the filter.

[0069] Table 5

[0070] Table 6

[0071] After simulation test, the results are as follows Fig. 8A and Figure 8B As shown, Fig. 8A is a distortion curve diagram of the periscope lens in Example 3, Figure 8B : is a magnification chromatic aberration curve of the periscope lens in Example 3. FIG. 8A to FIG. 8B It can be seen that the periscope lens of Example 3 can achieve good imaging quality.

[0072] The optical parameters of Examples 1 to 3 are shown in Table 7: Table 7

[0073] The black material data corresponding to the structures of Examples 1 to 3 are shown in Table 8: Table 8

[0074] The relationship satisfied by the data of Examples 1 to 3 is shown in Table 9: Table 9

[0075] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described 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.

[0076] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A periscope lens, characterized in that: include: A lens barrel having an object side end surface and an image side end surface; A lens group is mounted on the lens barrel, wherein the lens group includes a first lens, a second lens with positive optical power, a third lens with negative optical power, a fourth lens with negative optical power, a fifth lens and a sixth lens which are arranged in sequence from the object side end surface to the image side end surface and arranged on the same optical axis; a spacer element group, mounted on the lens barrel, the spacer element group comprising a first spacer element disposed on the image side of the first lens and abutting against the image side surface of the first lens, a second spacer element disposed on the image side of the second lens and abutting against the image side surface of the second lens, a third spacer element disposed on the image side of the third lens and abutting against the image side surface of the third lens, a fourth spacer element disposed on the image side of the fourth lens and abutting against the image side surface of the fourth lens, and a fifth spacer element disposed on the image side of the fifth lens and abutting against the image side surface of the fifth lens; as well as a prism, disposed on the object side of the lens barrel and having a reflective surface, wherein the reflective surface is arranged obliquely to the optical axis of the lens group and an angle between a normal line of the reflective surface and the optical axis of the lens group is an acute angle; The air gap T34 between the third lens and the fourth lens on the optical axis, the air gap T45 between the fourth lens and the fifth lens on the optical axis, the object side inner diameter d3s of the third spacer element, the image side inner diameter d3m of the third spacer element, the object side inner diameter d4s of the fourth spacer element, the image side inner diameter d4m of the fourth spacer element, and the object side inner diameter d5s of the fifth spacer element satisfy the following conditions: 0.33≤(T34+T45) / L≤0.37; 0.10≤(d4m-d3s) / d3m<0.85; and 0.29<(d5s-d3m) / d4s<0.

6.

2. The periscope lens according to claim 1, characterized in that: The prism also has an incident surface and an exit surface located on both sides of the reflecting surface, the incident surface and the exit surface are both spherical surfaces, the incident surface is convex, and the exit surface is concave, and the axial distance Y from the intersection of the incident surface and the optical axis to the image side surface of the sixth lens satisfies: 23.90 mm <Y<24.15mm。 3. The periscope lens according to any one of claim 1 or claim 2, characterized in that: The maximum height L of the lens barrel and the effective focal length f of the periscope lens satisfy the following conditions: 0.35 <L / f<0.51。 4. The periscope lens according to any one of claims 1 or 2, characterized in that: An air gap T34 on the optical axis between the third lens and the fourth lens, an air gap T45 on the optical axis between the fourth lens and the fifth lens, a maximum thickness CP3 of the third spacing element, and a maximum thickness CP4 of the fourth spacing element satisfy the following: 1.30<(T34+T45) / (CP3+CP4)<4.

75.

5. The periscope lens according to any one of claim 1 or claim 2, characterized in that: The positive and negative properties of the optical power of the first lens and the optical power of the sixth lens are the same, and the positive and negative properties of the optical power of the fifth lens and the optical power of the sixth lens are different; The effective focal length f5 of the fifth lens, the object side inner diameter d5s of the fifth spacing element, and the object side inner diameter d4s of the fourth lens satisfy the following relationship: 4.5<|f5 / (d5s-d4s)|<11.

85.

6. The periscope lens according to any one of claim 1 or claim 2, characterized in that: The effective focal length f3 of the third lens, the air gap T34 between the third lens and the fourth lens on the optical axis, and the object side inner diameter d3s of the third spacing element satisfy: -2.15 mm -1 <f3 / T34 / d3s<-1.00mm -1 .

7. The periscope lens according to claim 1, characterized in that: The spacing distance EP12 between the first spacing element and the second spacing element along the optical axis, the spacing distance EP23 between the second spacing element and the third spacing element along the optical axis, and the center thickness CT2 of the second lens satisfy: 1.40<(EP12+EP23) / CT2<2.

05.

8. The periscope lens according to claim 1, characterized in that: The sum of the maximum thicknesses ∑CP1 of all spacing elements between the first lens and the second lens, the air gap T12 between the first lens and the second lens on the optical axis, the maximum thickness CP2 of the second spacing element, and the air gap T23 between the second lens and the third lens on the optical axis satisfy: 5.55<∑CP1 / T12+CP2 / T23<12.

15.

9. The periscope lens according to claim 1, characterized in that: The maximum thickness CP2 of the second spacer element, the spacing distance EP23 between the second spacer element and the third spacer element along the optical axis, and the center thickness CT3 of the third lens satisfy the following: 1.85<(CP2+EP23) / CT3<2.

75.

10. The periscope lens according to any one of claims 7 to 9, characterized in that: The object side inner diameter d0s of the lens barrel and the object side inner diameter d1s of the first spacing element satisfy: 1.00 <d0s / d1s<1.41。 11. The periscope lens according to any one of claims 7 to 9, characterized in that: The image side inner diameter d0m of the lens barrel and the image side outer diameter D5m of the fifth spacer element satisfy the following: 1.05≤d0m / D5m≤1.

10.

12. The periscope lens according to any one of claims 7 to 9, characterized in that: The maximum thickness CP4 of the fourth spacer element, the spacing distance EP45 between the fourth spacer element and the fifth spacer element along the optical axis, and the effective focal length f5 of the fifth lens satisfy: -0.22≤(CP4+EP45) / f5≤0.20, and (CP4+EP45) / f5≠0.

13. The periscope lens according to any one of claims 7 to 9, characterized in that: The minimum aperture d0smin of the lens barrel on the object side and the inner diameter d3s of the third spacing element on the object side satisfy the following conditions: 0.85 <d0smin / d3s<1.30。

Images