Ultra-wide-angle optical lens

Abstract

The invention discloses an ultra-wide-angle optical lens which comprises an optical lens group, the optical lens group is provided with an optical axis, and the optical lens group is sequentially provided with a first lens, a second lens, a third lens, a fourth lens and a fifth lens from the object space to the image space along the optical axis. A diaphragm is arranged between the third lens and the fourth lens, the first lens, the second lens and the fourth lens have negative focal power, and the third lens and the fifth lens have positive focal power; the optical lens group satisfies the following relational expression: F2 * F3 / F1 is greater than or equal to 1.45; iH / EFL > = 1.9; fOV / (D * TTL) > = 1.2; wherein F1, F2 and F3 are the effective focal lengths of the first lens, the second lens and the third lens respectively, IH is the maximum image plane height of the optical lens group, EFL is the equivalent focal length of the optical lens group, FOV is the maximum field angle of the optical lens group, D is the head aperture size of the optical lens group, and TTL is the total optical length of the optical lens group. According to the invention, a 220-degree ultra-wide-angle field of view is realized, and the miniaturization and imaging quality of the optical lens are ensured at the same time.

Description

Technical Field

[0001] The present application relates to the technical field of optical lenses, and in particular to an ultra-wide-angle optical lens. Background Art

[0002] In recent years, the automotive industry has developed rapidly, and people have gradually proposed the concepts of assisted driving and autonomous driving. Car cameras have become an indispensable part of automotive parts, and car lenses, as core components of car cameras, play a very important role, especially wide-angle lenses in car lenses. This kind of lens is often used in car blind spot monitoring and 360° real-time imaging. With the popularization of the adaptation of this kind of car wide-angle lens, people's requirements for this kind of lens are getting higher and higher. At the same time, with the complexity of the car system, the installation space of the car lens is compressed smaller and smaller. In order to take into account the demand for miniaturization of lenses, conventional car wide-angle lenses on the market generally make sacrifices in imaging quality, field of view and cost.

[0003] Conventional automotive wide-angle lenses currently on the market usually achieve the demand for lens miniaturization by reducing image quality, reducing field of view or increasing material costs. Therefore, how to achieve ultra-wide-angle and compact structure design while ensuring high imaging quality has become an important issue facing the current optical lens field. Summary of the invention

[0004] In order to solve the problem that conventional vehicle-mounted wide-angle lenses cannot achieve both miniaturization and clear imaging, the present application provides an ultra-wide-angle optical lens that achieves the design requirements of ultra-wide angle, high imaging quality and compact structure.

[0005] An ultra-wide-angle optical lens, comprising an optical lens group, the optical lens group having an optical axis, the optical lens group sequentially arranged along the optical axis from the object side to the image side, a first lens, a second lens, a third lens, a fourth lens and a fifth lens, an aperture stop being arranged between the third lens and the fourth lens, the first lens, the second lens and the fourth lens having negative optical power, and the third lens and the fifth lens having positive optical power; The optical lens group satisfies the following relationship: F2*F3 / F1|≥1.45; IH / EFL ≥ 1.9; FOV / (D*TTL)≥1.2; Among them, F1, F2, and F3 are the effective focal lengths of the first lens, the second lens, and the third lens respectively, IH is the maximum image plane height of the optical lens group, EFL is the equivalent focal length of the optical lens group, FOV is the maximum field of view of the optical lens group, D is the head aperture size of the optical lens group, and TTL is the total optical length of the optical lens group.

[0006] By adopting the above technical solution and setting the ratio between the image height and the effective focal length, the 220° ultra-wide angle of the lens is realized; by reasonably allocating the optical power of the first lens, the second lens, and the third lens, the requirement of clear imaging of the 220° ultra-wide angle of light is realized, so that the lens can achieve good clarity while achieving an ultra-wide angle, and by controlling the relationship between the maximum field of view angle and the head aperture size and the total optical length, the miniaturization of the optical lens group is realized. Through theoretical calculation and analysis of the reflection and refraction optical system, the initial configuration of the optical system is determined, which effectively improves the problem of low imaging quality.

[0007] Preferably, the optical lens group further satisfies the following relationship: FOV / 2 / α4≥1.8; wherein α4 is the angle between the tangent of the arc length at the maximum aperture of the fourth surface and the optical axis.

[0008] By adopting the above technical solution, the surface angle of the second lens facing the image plane (i.e., the fourth surface from the object side to the image side) is small, which is beneficial to improving the lens demoulding efficiency while achieving an ultra-wide angle of 220°, thereby reducing mass production costs and improving production efficiency.

[0009] Preferably, the total optical length TTL of the optical lens further satisfies the following relationship: TTL≤12.7 mm.

[0010] By adopting the above technical solution, the range of the total optical length is specified, so that the lens is more miniaturized, meets the demand for miniaturization, and is suitable for smaller and smaller installation spaces.

[0011] Preferably, the second lens, the third lens, the fourth lens and the fifth lens are all aspherical lenses.

[0012] By adopting the above technical solution and adding the design of the aspherical lens, the aberration can be corrected better, thereby further improving the imaging quality.

[0013] Preferably, the refractive index of the first lens is Nd1, and Nd1≤1.75; the lower half aperture of the maximum field of view of the ultra-wide-angle optical lens is less than 5.8 mm.

[0014] By adopting the above technical solution, the size of the lens head is miniaturized, the assembly space is saved, and a high cost performance is achieved.

[0015] Preferably, the first lens is a negative meniscus lens convex to the object side, the second lens is a negative meniscus lens convex to the object side, the third lens is a biconvex positive lens, the fourth lens is a negative meniscus lens convex to the object side, and the fifth lens is a biconvex positive lens; The optical lenses are, in order along the optical path, a negative meniscus lens convex toward the object, a negative meniscus lens convex toward the object, a double convex positive lens, an aperture, a negative meniscus lens convex toward the object, and a double convex positive lens.

[0016] By adopting the above technical solution, the combination mode and parameters of multiple optical lenses work together to adjust the optical path of the incident light, which is conducive to balanced adjustment of the light transmitted from multiple directions and improves the imaging quality.

[0017] Preferably, the first lens is a convex meniscus negative lens, the second lens is a double concave negative lens, the third lens is a double convex positive lens, the fourth lens is a convex object negative meniscus lens, and the fifth lens is a double convex positive lens; the optical lenses are, in order along the optical path, a convex object negative meniscus lens, a double concave negative lens, a double convex positive lens, an aperture, a convex object negative meniscus lens, and a double convex positive lens.

[0018] Preferably, the first lens is a convex meniscus negative lens, the second lens is a convex meniscus negative lens, the second lens is a double concave negative lens, the fourth lens is a double concave negative lens, and the fifth lens is a double convex positive lens; the optical lenses are, in order along the optical path, a convex meniscus negative lens, a convex object negative meniscus negative lens, a double convex positive lens, an aperture, a double concave negative lens, and a double convex positive lens.

[0019] Preferably, the fourth lens and the fifth lens are cemented lenses.

[0020] By adopting the above technical solution, a cemented lens is used to correct the aberration of the optical lens, thereby eliminating or balancing the chromatic aberration produced by the lens, reducing the assembly sensitivity of the optical system, improving the imaging resolution of the optical imaging lens, and also reducing the cost.

[0021] Preferably, the second lens, the third lens, the fourth lens and the fifth lens are all made of plastic.

[0022] By adopting the above technical solution and using lenses made of plastic, the material cost is reduced.

[0023] In summary, this application at least includes the following beneficial effects: (1) The present application adopts a catadioptric optical system configuration and a specific optical relationship design, so that the optical lens of the present application achieves the design requirements of ultra-wide angle while ensuring high imaging quality. The field of view angle can reach 220°, achieving the final effect of ultra-wide-angle light input and clear imaging.

[0024] (2) The present application reasonably sets the material and shape of the lens so that the aperture and total length of the lens are kept at a very small value, thus achieving the requirement of miniaturization of the lens; at the same time, the specific shape of the lens can improve the lens demolding efficiency and thus reduce production costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a lens layout diagram of the ultra-wide-angle optical lens of the present application; Figure 2 1 is a schematic diagram of the optical path of the ultra-wide-angle optical lens of Example 1 of the present application; Figure 3 is an optical transfer function diagram of the ultra-wide-angle optical lens of Example 1 of the present application; Figure 4 Schematic diagram of the optical path of the ultra-wide-angle optical lens of Example 2 of the present application; Figure 5 Schematic diagram of the optical path of the ultra-wide-angle optical lens of Example 3 of the present application; Figure 6 yes Figure 2 The visual angle diagram formed by the displayed light path; Figure 7 This is a 220° ultra-wide-angle field of view of the ultra-wide-angle optical lens of this application.

[0026] Description of reference numerals: 1. First lens; 2. Second lens; 3. Third lens; 4. Fourth lens; 5. Fifth lens; 6. Aperture; 7. Filter; 8. Protective glass. DETAILED DESCRIPTION

[0027] The present application provides an ultra-wide-angle optical lens. In order to make the purpose, technical solution and advantages of the present application clearer, the implementation method of the present application will be further described in detail below.

[0028] The technical solutions in some embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the specification. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments.

[0029] It should be noted that in this specification, the expressions of first, second, third, etc. are only used to distinguish one feature from another feature, and do not represent any limitation on the features. Therefore, without departing from the present invention, the first lens discussed below may also be referred to as the second lens or the third lens.

[0030] An embodiment of the present application discloses an ultra-wide-angle optical lens, including an optical lens group, the optical lens group having an optical axis, the optical lens group being sequentially arranged along the optical axis from the object side to the image side with a first lens 1, a second lens 2, a third lens 3, a fourth lens 4 and a fifth lens 5, and an aperture 6 (i.e., STO) being arranged between the third lens 3 and the fourth lens 4.

[0031] The first lens 1 , the second lens 2 , and the fourth lens 4 have negative refractive power, and the third lens 3 and the fifth lens 5 have positive refractive power.

[0032] The first lens 1 has a first surface S1 and a second surface S2, the second lens 2 has a third surface S3 and a fourth surface S4, the third lens 3 has a fifth surface S5 and a sixth surface S6, and the cemented lens: the fourth lens 4 and the fifth lens 5 have an eighth surface S8, a ninth surface S9 and a tenth surface S10, and the seventh surface (not marked in the figure) between the sixth surface S6 and the eighth surface S8 is the aperture 6.

[0033] The optical lens group satisfies the following relationship: The effective focal length F1 of the first lens 1, the effective focal length F2 of the second lens 2, and the effective focal length F3 of the third lens 3 satisfy: |F2*F3 / F1|≥1.45; The maximum image plane height IH and the equivalent focal length EFL of the optical lens group satisfy the following conditions: IH / EFL ≥ 1.9; The maximum field of view FOV of the optical lens group, the head aperture size D of the optical lens group and the total optical length TTL satisfy: FOV / (D*TTL)≥1.2; the total optical length is the distance from the center of the object side of the first lens 1 to the imaging surface.

[0034] The maximum field of view FOV of the optical lens group and the angle α4 between the tangent of the arc length at the maximum aperture of the fourth surface and the optical axis satisfy: FOV / 2 / α4≥1.8; this condition controls the second lens 2 to have a smaller angle toward the image surface, that is, to make the fourth mirror surface from the object side to the image side: that is, the fourth surface S4 is smaller. Such a shape is easy to demold, improves production efficiency, and reduces mass production costs.

[0035] The total optical length TTL meets the requirement of TTL≤12.7mm.

[0036] The refractive index Nd1 of the first lens 1 satisfies: Nd1≤1.75; the lower half aperture of the maximum field of view of the ultra-wide-angle optical lens is less than 5.8 mm, which realizes the miniaturization of the lens head size, saves assembly space, and has a high cost performance.

[0037] By satisfying the above conditions and constraining the ratio of the above data, the length of the lens can be effectively limited, so that the lens can meet the requirements of structural miniaturization while also having an ultra-wide-angle field of view and ensuring imaging clarity.

[0038] In the embodiment of the present application, the optical focal length is reasonably controlled by the third lens 3 so that the total optical length TTL of the optical lens group is ≤12.7 mm to meet the demand for miniaturization of the lens group.

[0039] In the embodiment of the present application, the second lens 2, the third lens 3, the fourth lens 4 and the fifth lens 5 are all aspherical lenses, and the materials of the second lens 2, the third lens 3, the fourth lens 4 and the fifth lens 5 are all plastic.

[0040] The imaging quality can be effectively improved by increasing the number of aspherical lenses, while making them out of plastic helps save costs.

[0041] In the embodiment of the present application, the fourth lens 4 and the fifth lens 5 are cemented lenses. The cementation of lenses can effectively improve the chromatic aberration of the optical system, reduce the assembly sensitivity of the system, and reduce the cost.

[0042] In the embodiment of the present application, the aperture 6 is placed between the third lens 3 and the cemented lens, and the light of the lens group before the transition aperture 6 is conducive to shortening the total length of the optical lens group. By adjusting the size of the aperture, the clarity and brightness of the image can be balanced.

[0043] In an embodiment of the present application, arranged in sequence from the object side to the image side are: a first lens 1, a second lens 2, a third lens 3, an aperture 6, a fourth lens 4, a fifth lens 5, a filter 7 and a protective glass 8, wherein the filter 7 has an eleventh surface S11 and a twelfth surface S12, and the protective glass 8 has a thirteenth surface S13 and a fourteenth surface S14.

[0044] Embodiment 1: In Example 1, Figure 1 As shown, the first lens 1 is a negative meniscus lens convex to the object side, the second lens 2 is a negative meniscus lens convex to the object side, the third lens 3 is a double convex positive lens, the fourth lens 4 is a negative meniscus lens convex to the object side, and the fifth lens 5 is a double convex positive lens; like Figure 2 As shown, the optical lenses are, in order along the optical path, a negative meniscus lens convex toward the object, a negative meniscus lens convex toward the object, a double convex positive lens, an aperture 6, a negative meniscus lens convex toward the object, a double convex positive lens, a filter 7 and a protective glass 8.

[0045] The negative meniscus lens convex toward the object as the first lens 1 has negative optical power. The curved shape of the first lens 1 convex toward the object is conducive to collecting large-angle light of the lens and is more conducive to the sliding of liquids such as raindrops.

[0046] The convex object-side meniscus negative lens as the second lens 2 has negative optical power, which can fine-tune the light collected by the first lens 1 and make the light smoothly transition to the rear optical system, which is beneficial to make the picture brightness more uniform and improve the imaging quality of the optical lens.

[0047] The double convex positive lens as the third lens 3 has positive focal power, which can compress the light and make it enter the aperture smoothly, which is beneficial to increase the aperture diameter and increase the light throughput of the system; and the aspherical third lens 3 made of plastic material has a better light converging effect, which is beneficial to improve the resolution.

[0048] In this embodiment 1, the convex object-side meniscus negative lens as the fourth lens 4 and the double convex positive lens as the fifth lens 5 are cemented together to form a cemented lens, which can eliminate or balance the chromatic aberration produced by the lens and reduce the tolerance sensitivity; and both are plastic lenses, which can effectively reduce costs.

[0049] Based on the structure of the optical lens provided in the above-mentioned Example 1, when the optical lens sequentially includes a convex meniscus negative lens, a convex meniscus negative lens, a double convex positive lens, an aperture 6, a convex object negative meniscus negative lens, a double convex positive lens, a filter 7 and a protective glass 8, Table 1 shows various parameters of multiple optical lenses of the optical lens.

[0050] Table 1: like Figure 2 As shown, the object side surface S1 of the first lens 1, i.e., the negative meniscus lens convex toward the object, is convex, and the image side surface S2 is concave; The object side surface S3 of the second lens 2, i.e., the negative meniscus lens convex toward the object, is convex, and the image side surface S4 is concave; The object side surface S5 of the third lens 3, i.e., the biconvex positive lens, is convex, and the image side surface S6 is convex; The fourth lens 4, i.e., the negative meniscus lens convex toward the object, has an object side surface S8 that is convex, and an image side surface S9 that is concave; The object side surface S9 of the fifth lens element 5, i.e., the biconvex positive lens, is convex, and the image side surface S10 is convex; The fourth lens 4 and the fifth lens 5 are glued together and share S9, so S9 is concave relative to the fourth lens 4 and is convex relative to the fifth lens 5.

[0051] The object side surface of the filter 7 is S11, and the image side surface is S12; the object side surface of the protective glass 8 is S13, and the image side surface is S14, and IMA is an imaging surface.

[0052] Furthermore, the second lens 2, the third lens 3, the fourth lens 4 and the fifth lens 5 in the embodiments of the present application are aspherical surfaces, satisfying the following equations: Among them, Z(h) is the distance vector height from the vertex of the aspherical surface when the aspherical surface is at a height h along the main optical axis; c=1 / r, c is the curvature of the pole of the aspherical surface, r represents the curvature radius of the mirror surface, k is the cone coefficient, A, B, C, D, E, F, G are high-order aspherical coefficients.

[0053] Furthermore, parameters of the object-side surface and the image-side surface of the second lens 2 , the third lens 3 , the fourth lens 4 , and the fifth lens 5 are shown in Table 2.

[0054] Table 2: The parameters of the optical lens of this embodiment 1 are shown in Table 3.

[0055] Table 3: FOV 220 <![CDATA[α4]]> 53.8245 F1 -5.8521 F2 -2.4231 F3 3.8330 EFL 0.9629 IH 1.92 Nd1 1.7400 D 14.00 TTL 12.70 In this embodiment 1, the relationship between the maximum field of view FOV of the optical lens assembly and the angle α4 between the tangent of the arc length at the maximum aperture of the fourth surface and the optical axis is: FOV / 2 / α4=2.0437, satisfying the relationship FOV / 2 / α4≥1.8; The relationship between the effective focal length F1 of the first lens 1, the effective focal length F2 of the second lens 2, and the effective focal length F3 of the third lens 3 is: |F2*F3 / F1|=1.5871, satisfying the relationship |F2*F3 / F1|≥1.45; The relationship between the maximum image plane height IH of the optical lens group and the equivalent focal length EFL of the optical lens group is: IH / EFL=1.9940, satisfying the relationship IH / EFL≥1.95; The refractive index of the first lens 1 is Nd1=1.74, satisfying the relationship Nd1≤1.75; The relationship between the maximum field of view FOV of the optical lens group, the head aperture size D of the optical lens group and the total optical length TTL of the optical lens group is: FOV / (D*TTL)=1.2373, satisfying the relationship FOV / (D*TTL)≥1.2.

[0056] The optical transfer function of the optical lens of this embodiment is shown in FIG. Figure 3 As shown, it can be seen that the imaging quality of the optical lens from the center to the edge of the field of view is very uniform, that is, the imaging quality of this embodiment is high and the entire image is very clear.

[0057] In summary, the optical lens of this embodiment can achieve the ultra-wide-angle requirement while ensuring high imaging quality, and the field of view angle can reach 220°, achieving the final effect of clear ultra-wide-angle light input imaging.

[0058] Embodiment 2: In another specific embodiment 2 of the present application, Figure 4 As shown, the first lens 1 is a negative meniscus lens convex to the object side, the second lens 2 is a double concave negative lens, the third lens 3 is a double convex positive lens, the fourth lens 4 is a negative meniscus lens convex to the object side, and the fifth lens 5 is a double convex positive lens; The optical lenses are, in order along the optical path, a negative meniscus lens convex toward the object, a double concave negative lens, a double convex positive lens, an aperture 6, a negative meniscus lens convex toward the object, a double convex positive lens, a filter 7 and a protective glass 8.

[0059] The negative meniscus lens convex toward the object as the first lens 1 has negative optical power. The curved shape of the first lens 1 convex toward the object is conducive to collecting large-angle light of the lens and is more conducive to the sliding of liquids such as raindrops.

[0060] The double concave negative lens as the second lens 2 has negative optical power, can collect the light from the first lens 1 and make fine adjustments so that the light enters the rear lens group, which is helpful to avoid excessive dispersion of light and cause the rear lens to have an excessively large aperture.

[0061] The double convex positive lens as the third lens 3 has positive focal power, which can compress the light and make it enter the aperture smoothly, which is beneficial to increase the aperture diameter and increase the light throughput of the system; and the aspherical third lens 3 made of plastic material has a better light converging effect, which is beneficial to improve the resolution.

[0062] In this embodiment, a convex object-side meniscus negative lens as the fourth lens 4 and a double convex positive lens as the fifth lens 5 are cemented together to form a cemented lens, which can eliminate or balance the chromatic aberration produced by the lens and reduce tolerance sensitivity; and both are plastic lenses, which can effectively reduce costs.

[0063] Based on the structure of the optical lens provided in the above-mentioned embodiment 2, when the optical lens sequentially includes a convex meniscus negative lens, a biconcave negative lens, a biconvex positive lens, an aperture 6, a convex object negative meniscus negative lens, a biconvex positive lens, a filter 7 and a protective glass 8, Table 4 shows various parameters of multiple optical lenses of the optical lens.

[0064] Table 4: Furthermore, the second lens 2, the third lens 3, the fourth lens 4 and the fifth lens 5 in the embodiments of the present application are aspherical surfaces, satisfying the following equations: Among them, Z(h) is the distance vector height from the vertex of the aspherical surface when the aspherical surface is at a height h along the main optical axis; c=1 / r, c is the curvature of the pole of the aspherical surface, r represents the curvature radius of the mirror surface, k is the cone coefficient, A, B, C, D, E, F, G are high-order aspherical coefficients.

[0065] Furthermore, parameters of the object-side surface and the image-side surface of the second lens 2 , the third lens 3 , the fourth lens 4 , and the fifth lens 5 are shown in Table 5.

[0066] Table 5: The parameters of the optical lens of this embodiment 2 are shown in Table 6.

[0067] Table 6: FOV 220 <![CDATA[α4]]> 60.5700 F1 -6.0431 F2 -2.2170 F3 4.0190 EFL 0.9558 IH 1.92 Nd1 1.7400 D 14.20 TTL 12.70 In the second embodiment, the relationship between the maximum field of view FOV of the optical lens assembly and the angle α4 between the tangent of the arc length at the maximum aperture of the fourth surface and the optical axis is: FOV / 2 / α4=1.8161, satisfying the relationship FOV / 2 / α4≥1.8; The relationship between the effective focal length F1 of the first lens 1, the effective focal length F2 of the second lens 2, and the effective focal length F3 of the third lens 3 is: |F2*F3 / F1|=1.4745, satisfying the relationship |F2*F3 / F1|≥1.45; The relationship between the maximum image plane height IH of the optical lens group and the equivalent focal length EFL of the optical lens group is: IH / EFL=2.0089, satisfying the relationship IH / EFL≥1.95; The refractive index of the first lens 1 is Nd1=1.7400, satisfying the relationship Nd1≤1.75; The relationship between the maximum field of view FOV of the optical lens group, the head aperture size D of the optical lens group and the total optical length TTL of the optical lens group is: FOV / (D*TTL)=1.2199, satisfying the relationship FOV / (D*TTL)≥1.2.

[0068] Embodiment 3: In another specific embodiment 3 of the present application, Figure 5 As shown, the first lens 1 is a convex meniscus negative lens toward the object, the second lens 2 is a convex meniscus negative lens toward the object, the second lens 2 is a double concave negative lens, the fourth lens 4 is a double concave negative lens, and the fifth lens 5 is a double convex positive lens; The optical lenses are, in order along the optical path, a negative meniscus lens convex toward the object, a negative meniscus lens convex toward the object, a double convex positive lens, an aperture 6, a double concave negative lens, and a double convex positive lens.

[0069] The negative meniscus lens convex toward the object as the first lens 1 has negative optical power. The curved shape of the first lens 1 convex toward the object is conducive to collecting large-angle light of the lens and is more conducive to the sliding of liquids such as raindrops.

[0070] The convex object-side meniscus negative lens as the second lens 2 has negative optical power, which can fine-tune the light collected by the first lens 1 and make the light smoothly transition to the rear optical system, which is beneficial to make the picture brightness more uniform and improve the imaging quality of the optical lens.

[0071] The double convex positive lens as the third lens 3 has positive focal power, which can compress the light and make it enter the aperture smoothly, which is beneficial to increase the aperture diameter and increase the light throughput of the system; and the aspherical third lens 3 made of plastic material has a better light converging effect, which is beneficial to improve the resolution.

[0072] In this embodiment, a double concave negative lens as the fourth lens 4 and a double convex positive lens as the fifth lens 5 are cemented to form a cemented lens, which can eliminate or balance the chromatic aberration produced by the lens and reduce tolerance sensitivity; and both are plastic lenses, which can effectively reduce costs.

[0073] Based on the structure of the optical lens provided in the above-mentioned Example 3, when the optical lens sequentially includes a convex meniscus negative lens, a convex object negative meniscus negative lens, a double convex positive lens, an aperture 6, a double concave negative lens, a double convex positive lens, a filter 7 and a protective glass 8, Table 7 shows various parameters of multiple optical lenses of the optical lens.

[0074] Table 7: Furthermore, the second lens 2, the third lens 3, the fourth lens 4 and the fifth lens 5 in the embodiments of the present application are aspherical surfaces, satisfying the following equations: Among them, Z(h) is the distance vector height from the vertex of the aspherical surface when the aspherical surface is at a height h along the main optical axis; c=1 / r, c is the curvature of the pole of the aspherical surface, r represents the curvature radius of the mirror surface, k is the cone coefficient, A, B, C, D, E, F, G are high-order aspherical coefficients.

[0075] Furthermore, parameters of the object-side surface and the image-side surface of the second lens 2 , the third lens 3 , the fourth lens 4 , and the fifth lens 5 are shown in Table 8.

[0076] Table 8: The parameters of the optical lens of this embodiment 3 are shown in Table 9.

[0077] Table 9: FOV 220 <![CDATA[α4]]> 56.6319 F1 -5.8366 F2 -2.5630 F3 4.6102 EFL 0.9598 IH 1.92 Nd1 1.7400 D 14.00 TTL 12.70 In this embodiment 3, the relationship between the maximum field of view FOV of the optical lens assembly and the angle α4 between the tangent of the arc length at the maximum aperture of the fourth surface and the optical axis is: FOV / 2 / α4=1.9424, satisfying the relationship FOV / 2 / α4≥1.8; The relationship between the effective focal length F1 of the first lens 1, the effective focal length F2 of the second lens 2, and the effective focal length F3 of the third lens 3 is: |F2*F3 / F1|=2.0245, satisfying the relationship |F2*F3 / F1|≥1.45; The relationship between the maximum image plane height IH of the optical lens group and the equivalent focal length EFL of the optical lens group is: IH / EFL=2.0005, satisfying the relationship IH / EFL≥1.95; The refractive index of the first lens 1 is Nd1=1.7400, satisfying the relationship Nd1≤1.75; The relationship between the maximum field of view FOV of the optical lens group, the head aperture size D of the optical lens group and the total optical length TTL of the optical lens group is: FOV / (D*TTL)=1.2372, satisfying the relationship FOV / (D*TTL)≥1.2.

[0078] Reference Figure 6 and Figure 7 , is a field of view diagram that can be obtained by the embodiment of the present application, wherein Figure 6 is half the viewing angle formed by the optical path shown in Example 1, Figure 7 The 220° ultra-wide-angle field of view formed by the complete optical path of this embodiment is demonstrated.

[0079] In summary, the optical lens group of the present application achieves the requirement of miniaturization of the lens by reasonably matching the lens shape and optical focal length of each lens, reducing the aperture and total optical length of the lens, and realizes the requirement of low cost by reasonably selecting a glass-plastic hybrid structure. By reasonably allocating the optical focal length of the lens, the requirement of clear imaging within the range of 220° ultra-wide-angle field of view is achieved, and at the same time has the advantages of ultra-wide-angle field of view, miniaturization and clear imaging.

[0080] The above are only optional embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. An ultra-wide-angle optical lens, characterized in that: The optical lens group comprises an optical axis, wherein the optical lens group comprises a first lens (1), a second lens (2), a third lens (3), a fourth lens (4) and a fifth lens (5) arranged in sequence along the optical axis from the object side to the image side, an aperture (6) is arranged between the third lens (3) and the fourth lens (4), the first lens (1), the second lens (2) and the fourth lens (4) have negative optical power, and the third lens (3) and the fifth lens (5) have positive optical power; The optical lens group satisfies the following relationship: F2*F3 / F1|≥1.45; IH / EFL ≥ 1.9; FOV / (D*TTL)≥1.2; Wherein, F1, F2, and F3 are respectively the effective focal lengths of the first lens (1), the second lens (2), and the third lens (3); IH is the maximum image plane height of the optical lens group; EFL is the equivalent focal length of the optical lens group; FOV is the maximum field of view angle of the optical lens group; D is the head aperture size of the optical lens group; and TTL is the total optical length of the optical lens group.

2. The ultra-wide-angle optical lens according to claim 1, characterized in that: The optical lens assembly further satisfies the following relationship: FOV / 2 / α4≥1.8; wherein α4 is the angle between the tangent of the arc length at the maximum aperture of the fourth surface and the optical axis.

3. The ultra-wide-angle optical lens according to claim 1, characterized in that: The total optical length TTL of the optical lens further satisfies the following relationship: TTL≤12.7 mm.

4. The ultra-wide-angle optical lens according to claim 1, characterized in that: The second lens (2), the third lens (3), the fourth lens (4) and the fifth lens (5) are all aspherical lenses.

5. The ultra-wide-angle optical lens according to claim 1, characterized in that: The refractive index of the first lens (1) is Nd1, and Nd1≤1.75; the lower half aperture of the maximum field of view of the ultra-wide-angle optical lens is less than 5.8 mm.

6. The ultra-wide-angle optical lens according to claim 1, characterized in that: The first lens (1) is a negative meniscus lens convex toward the object, the second lens (2) is a negative meniscus lens convex toward the object, the third lens (3) is a double convex positive lens, the fourth lens (4) is a negative meniscus lens convex toward the object, and the fifth lens (5) is a double convex positive lens; The optical lenses are, in order along the optical path, a negative meniscus lens convex toward the object, a negative meniscus lens convex toward the object, a double convex positive lens, an aperture (6), a negative meniscus lens convex toward the object, and a double convex positive lens.

7. The ultra-wide-angle optical lens according to claim 1, characterized in that: The first lens (1) is a convex meniscus negative lens, the second lens (2) is a biconcave negative lens, the third lens (3) is a biconvex positive lens, the fourth lens (4) is a convex meniscus negative lens, and the fifth lens (5) is a biconvex positive lens; The optical lenses are, in order along the optical path, a negative meniscus lens convex toward the object, a double concave negative lens, a double convex positive lens, an aperture (6), a negative meniscus lens convex toward the object, and a double convex positive lens.

8. The ultra-wide-angle optical lens according to claim 1, characterized in that: The first lens (1) is a convex meniscus negative lens, the second lens (2) is a convex meniscus negative lens, the second lens (2) is a biconcave negative lens, the fourth lens (4) is a biconcave negative lens, and the fifth lens (5) is a biconvex positive lens; The optical lenses are, in order along the optical path, a meniscus negative lens convex toward the object, a meniscus negative lens convex toward the object, a double convex positive lens, an aperture (6), a double concave negative lens, and a double convex positive lens.

9. An ultra-wide-angle optical lens according to any one of claims 6 to 8, characterized in that: The fourth lens (4) and the fifth lens (5) are cemented lenses.

10. The ultra-wide-angle optical lens according to claim 1, characterized in that: The second lens (2), the third lens (3), the fourth lens (4) and the fifth lens (5) are all made of plastic.

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