Zoom optical system and image pickup apparatus

Abstract

The application discloses a zoom optical system and a camera device, the zoom optical system comprising a lens barrel and a lens group, the lens group comprising a first lens group with positive refractive power, a second lens group with negative refractive power, a third lens group with positive refractive power, a fourth lens group with negative refractive power, a fifth lens group with positive refractive power and a sixth lens group with negative refractive power arranged in sequence from the object side to the image side, the image surface size is set to phi 9.4 mm, through reasonable setting of the six lens groups and conditional restriction of the wide-angle end focal length of the zoom optical system and the focal length ratio of each lens group, the aperture F number of the zoom optical system can reach 1.08, under such aperture number, more light quantity can be obtained in a weak light environment, the multi-aspherical lens is combined with the multi-ZOOM group structure, and the imaging quality is ensured, so that the imaging quality under weak light and long focal length is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of optical system design, in particular to a zoom optical system applied to a monitoring system and a camera device. BACKGROUND

[0002] The mainstream high-image-quality monitoring system zoom lens on the market has a small aperture, and the effect is not ideal in a weak light environment, or the performance decreases sharply at a long focal length, which cannot meet the market demand. SUMMARY

[0003] The main purpose of the present application is to provide a zoom optical system and a camera device, which aims to improve the imaging quality in weak light and at a long focal length.

[0004] To achieve the above purpose, the present application provides a zoom optical system, which has an object side and an image side arranged oppositely along an optical axis direction, and comprises:

[0005] a lens barrel; and

[0006] a plurality of lens groups arranged in the lens barrel, including a first lens group with positive focal power, a second lens group with negative focal power, a third lens group with positive focal power, a fourth lens group with negative focal power, a fifth lens group with positive focal power, a sixth lens group with negative focal power, and an image surface arranged in sequence from the object side to the image side, wherein the second lens group and the fourth lens group are movably arranged along the extension direction of the optical axis to zoom the zoom optical system, the fifth lens group moves cooperatively along the optical axis direction to focus the zoom optical system, and the image surface has a diameter of 9.4mm;

[0007] wherein the focal length of the zoom optical system at a wide-angle end is fw, the focal length of the first lens group is f1, the focal length of the second lens group is f2, the focal length of the third lens group is f3, the focal length of the fourth lens group is f4, the focal length of the fifth lens group is f5, the focal length of the sixth lens group is f6, and the zoom optical system satisfies the following conditions:

[0008] 0.163<fw / f1<0.221, and -1.278<fw / f2<-0.945, and 0.405<fw / f3<0.548, and -0.242<fw / f4<-0.179, and 0.424<fw / f5<0.574, and -0.321<fw / f6<-0.237.

[0009] Optionally, the first lens group comprises, from the object side to the image side, a first lens with positive refractive power, a second lens with negative refractive power, a third lens with positive refractive power, and a fourth lens with positive refractive power;

[0010] The first lens, the second lens, the third lens, and the fourth lens are all glass spherical lenses;

[0011] The first lens and the second lens are cemented together;

[0012] The focal length of the first lens is f11, the focal length of the second lens is f12, the focal length of the third lens is f13, and the focal length of the fourth lens is f14, and each lens in the first lens group satisfies the following conditions:

[0013] 0.058 < f1 / f11 < 0.086, and -0.662 < f1 / f12 < -0.441, and 0.427 < f1 / f13 < 0.641, and 0.29 < f1 / f14 < 0.435.

[0014] Optionally, the second lens group comprises, from the object side to the image side, a fifth lens with negative refractive power, a sixth lens with negative refractive power, a seventh lens with positive refractive power, and an eighth lens with negative refractive power;

[0015] The fifth lens, the sixth lens, and the seventh lens are all glass spherical lenses, and the eighth lens is a glass aspherical lens;

[0016] The sixth lens and the seventh lens are cemented together;

[0017] The focal length of the fifth lens is f21, the focal length of the sixth lens is f22, the focal length of the seventh lens is f23, and the focal length of the eighth lens is f24, and each lens in the second lens group satisfies the following conditions:

[0018] 0.372 < f2 / f21 < 0.558, and 0.082 < f2 / f22 < 0.123, and -0.11 < f2 / f23 < -0.073, and 0.219 < f2 / f24 < 0.328.

[0019] Optionally, the third lens group comprises, from the object side to the image side, a ninth lens with positive refractive power and a tenth lens with positive refractive power;

[0020] The ninth lens is a glass aspherical lens, and the tenth lens is a glass spherical lens;

[0021] A focal length of the ninth lens is f31, a focal length of the tenth lens is f32, and each lens in the third lens group satisfies the following conditions:

[0022] 0.243 < f3 / f31 < 0.365, and 0.619 < f3 / f32 < 0.928.

[0023] Optionally, the fourth lens group comprises an eleventh lens with negative refractive power, the eleventh lens being a glass aspheric lens; and / or,

[0024] The sixth lens group comprises a fifteenth lens with negative refractive power, the fifteenth lens being a glass spherical lens.

[0025] Optionally, the fifth lens group comprises, in order from the object side to the image side, a twelfth lens with positive refractive power, a thirteenth lens with negative refractive power, and a fourteenth lens with positive refractive power;

[0026] The twelfth lens and the thirteenth lens are glass spherical lenses, and the fourteenth lens is a glass aspheric lens;

[0027] The twelfth lens and the thirteenth lens are cemented together;

[0028] A focal length of the twelfth lens is f51, a focal length of the thirteenth lens is f52, and a focal length of the fourteenth lens is f53, and each lens in the fifth lens group satisfies the following conditions:

[0029] 0.015 < f5 / f51 < 0.023, and -0.72 < f5 / f52 < -0.480, and 1.008 < f5 / f53 < 1.511.

[0030] Optionally, the zoom optical system satisfies the following condition: 0.313 < øL11 / TTL < 0.383;

[0031] Wherein, øL11 is an effective clear aperture of the first lens, and TTL is an optical total length of the zoom optical system.

[0032] Optionally, the zoom optical system satisfies the following condition:

[0033] ;

[0034] Wherein, is a relative displacement of the second lens group when the zoom optical system is at a wide-angle end position and when the zoom optical system is at a telephoto end position, For a relative displacement of the fourth lens group when the zoom optical system is at the wide-angle end position and when the zoom optical system is at the telephoto end position, TTL is an overall optical length of the zoom optical system.

[0035] Optionally, the zoom optical system further comprises a stop, the stop being located between the second lens group and the third lens group.

[0036] Wherein, a distance of the stop to an image plane of the zoom optical system on the optical axis is L, an overall optical length of the zoom optical system is TTL, and within the zoom optical system: 0.435 < L / TTL < 0.532.

[0037] A camera device, the camera device comprising a zoom optical system, the zoom optical system having an object side and an image side oppositely arranged along an optical axis direction, the zoom optical system comprising:

[0038] A lens barrel; and,

[0039] A plurality of lens groups, disposed in the lens barrel, comprising a first lens group with positive refractive power, a second lens group with negative refractive power, a third lens group with positive refractive power, a fourth lens group with negative refractive power, a fifth lens group with positive refractive power, a sixth lens group with negative refractive power, and an image plane, arranged in order from the object side to the image side, wherein the second lens group and the fourth lens group are movably arranged along an extension direction of the optical axis to zoom the zoom optical system, the fifth lens group is moved cooperatively along the optical axis direction to focus the zoom optical system, and the image plane has a diameter of 9.4mm.

[0040] Wherein, a focal length of the zoom optical system at the wide-angle end is fw, a focal length of the first lens group is f1, a focal length of the second lens group is f2, a focal length of the third lens group is f3, a focal length of the fourth lens group is f4, a focal length of the fifth lens group is f5, and a focal length of the sixth lens group is f6, and the zoom optical system satisfies the following conditions:

[0041] 0.163 < fw / f1 < 0.221, and -1.278 < fw / f2 < -0.945, and 0.405 < fw / f3 < 0.548, and -0.242 < fw / f4 < -0.179, and 0.424 < fw / f5 < 0.574, and -0.321 < fw / f6 < -0.237.

[0042] In the technical scheme provided by the present application, the second lens group and the fourth lens group are movably mounted along the optical axis direction of the lens barrel for zooming, and the fourth lens group moves along the optical axis direction to make the zoom optical system zoom from the wide-angle end to the telephoto end, and the fifth lens group is driven by an external force to move along the optical axis direction corresponding to the positions, imaging wavelengths and imaging object distances of the second lens group and the fourth lens group, so that the zoom optical system keeps the image plane clear during zooming, and the first lens group has positive focal power, the second lens group has negative focal power, the third lens group has positive focal power, the fourth lens group has negative focal power, the fifth lens group has positive focal power, and the sixth lens group has negative focal power, through reasonable setting of the six lens groups and conditional restriction of the wide-angle end focal length of the zoom optical system and the focal length ratio of each lens group, the aperture F number of the zoom optical system can reach 1.08, so that more light can be introduced in a weak light environment, and the imaging quality is ensured through the combination of multiple aspherical lenses and the multiple ZOOM group structure, so as to improve the imaging quality in weak light and long focal length. BRIEF DESCRIPTION OF DRAWINGS

[0043] In order to more clearly illustrate the technical schemes in the embodiments of the present application or the prior art, the drawings needed in the following embodiment or prior art description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor on the basis of the drawings shown.

[0044] Figure 1 The structure schematic diagram of the first embodiment of the zoom optical system provided by the present application at the wide-angle end;

[0045] Figure 2 The structure schematic diagram of the zoom optical system at the intermediate magnification;

[0046] Figure 3 The structure schematic diagram of the zoom optical system at the telephoto end;

[0047] Figure 4 The aberration diagram of the zoom optical system in Figure 1 at the wide-angle end;

[0048] Figure 5 The field curvature / distortion diagram of the zoom optical system in Figure 1 at the wide-angle end;

[0049] Figure 6 The spherical aberration diagram of the zoom optical system in Figure 2 at the intermediate magnification;

[0050] Figure 7 is the field curvature / distortion map of the zoom optical system in the middle magnification of the zoom optical system in FIG. 1; Figure 2

[0051] is the aberration map of the zoom optical system in the telephoto end of the zoom optical system in FIG. 1; Figure 8 Figure 3

[0052] Figure 9 is the field curvature / distortion map of the zoom optical system in the telephoto end of the zoom optical system in FIG. 1; Figure 3

[0053] BRIEF DESCRIPTION OF DRAWINGS

[0054]

[0055] The implementation, functional features and advantages of the present application will be further described with reference to the accompanying drawings. DETAILED DESCRIPTION

[0056] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the protection scope of the present application.

[0057] It should be noted that if the directionality indication is involved in the embodiments of the present application, the directionality indication is only used to explain the relative position relationship, movement condition and the like between components in a certain posture, and if the certain posture is changed, the directionality indication is also changed accordingly.

[0058] In addition, if the description of "first", "second" and the like is involved in the embodiments of the present application, the description of "first", "second" and the like is only for the purpose of description, and cannot be understood as indicating or implying the relative importance of the indicated technical features or implicitly indicating the number of the indicated technical features. Therefore, the features limited by "first", "second" can explicitly or implicitly include at least one of the features. In addition, the meaning of "and / or" appearing throughout the text includes three parallel schemes. Taking "A and / or B" as an example, it includes A scheme, or B scheme, or A and B scheme. In addition, the technical solutions of each embodiment can be combined with each other, but it must be based on the realization of those skilled in the art. When the combination of technical solutions appears contradictory or unachievable, it should be considered that the combination of technical solutions does not exist, and is not within the protection scope of the present application.

[0059] ​​​The zoom lens of the mainstream high image quality monitoring system on the market is small in aperture, and the effect is not ideal in a weak light environment, or the performance is sharply reduced at a long focal length, which cannot meet the market demand.

[0060] The present application provides a zoom optical system, aiming at improving the technical problem that wide angle and small distortion cannot coexist in the prior art, please refer to Figures 1 to 9 , the specific embodiment of the zoom optical system is shown in the drawing.

[0061] Figures 1 to 9 An embodiment of the zoom optical system provided by the present application.

[0062] Please refer to Figures 1 to 3 , the zoom optical system has a relative arrangement along the optical axis direction of the object side and the image side, the zoom optical system includes a lens barrel (not shown in the figure) and a plurality of lens groups, the lens barrel is arranged along the extension direction of the optical axis, the lens groups are arranged in the lens barrel, the lens groups include a first lens group 1 with positive focal power, a second lens group 2 with negative focal power, a third lens group 3 with positive focal power, a fourth lens group 4 with negative focal power, a fifth lens group 5 with positive focal power, a sixth lens group 6 with negative focal power and an image surface 7 arranged in sequence from the object side to the image side, wherein the second lens group 2 and the fourth lens group 4 are movably arranged along the extension direction of the optical axis to zoom the zoom optical system, the fifth lens group 5 is moved along the optical axis direction to focus the zoom optical system, and the size of the image surface 7 is set to φ9.4mm.

[0063] It should be noted that the second lens group 2 and the fourth lens group 4 are moved along the extension direction of the optical axis to zoom, the fourth lens group 4 is moved along the optical axis direction to zoom the zoom optical system from the wide angle end to the telephoto end, and the fifth lens group 5 is driven by external force to move along the optical axis corresponding to the position, imaging wavelength and imaging object distance of the second lens group 2 and the fourth lens group 4 to focus, so that the image surface 7 of the zoom optical system remains clear during zooming.

[0064] It should be noted that the second lens group 2 and the fourth lens group 4 can be driven by external force to move along the optical axis direction, wherein the external force driving can be driven by a driving motor, or manually adjusted without limitation.

[0065] And, the focal length of the zoom optical system at the wide-angle end is fw, the focal length of the first lens group 1 is fl, the focal length of the second lens group 2 is f2, the focal length of the third lens group 3 is f3, the focal length of the fourth lens group 4 is f4, the focal length of the fifth lens group 5 is f5, the focal length of the sixth lens group 6 is f6, and the zoom optical system satisfies the following conditions: 0.163 < fw / fl < 0.221, and -1.278 < fw / f2 < -0.945, and 0.405 < fw / f3 < 0.548, and -0.242 < fw / f4 < -0.179, and 0.424 < fw / f5 < 0.574, and -0.321 < fw / f6 < -0.237.

[0066] In the technical scheme provided by the application, the second lens group 2 and the fourth lens group 4 are movably mounted on the lens barrel along the optical axis for zooming, and the fourth lens group 4 moves along the optical axis in coordination to make the zoom optical system zoom from the wide-angle end to the telephoto end, and the fifth lens group 5 is driven by an external force to move along the optical axis for focusing corresponding to the positions, imaging wavelengths and imaging object distances of the second lens group 2 and the fourth lens group 4, so that the zoom optical system keeps the image plane 7 clear during zooming, and the first lens group 1 has positive refractive power, the second lens group 2 has negative refractive power, the third lens group 3 has positive refractive power, the fourth lens group 4 has negative refractive power, the fifth lens group 5 has positive refractive power, and the sixth lens group 6 has negative refractive power, the image plane diameter is set to φ9.4mm, and through reasonable arrangement of the six lens groups and conditional restriction of the focal length ratio of the zoom optical system at the wide-angle end and each lens group, the aperture F number of the zoom optical system can reach 1.08, so that more light can be introduced in a weak light environment, and the imaging quality is ensured by the combination of multiple aspherical lenses and multiple zoom groups, thereby improving the imaging quality in a weak light environment and at a long focal length.

[0067] In a specific embodiment, the ratio of the focal length of the zoom optical system at the wide-angle end to the focal length of each lens group is as follows: fw / fl = 0.19; fw / f2 = -1.09; fw / f3 = 0.47; fw / f4 = -0.21; fw / f5 = 0.49; and fw / f6 = -0.27.

[0068] In particular, the first lens group 1 comprises, sequentially arranged from the object side to the image side, a first lens 11 with positive refractive power, a second lens 12 with negative refractive power, a third lens 13 with positive refractive power, and a fourth lens 14 with positive refractive power; the focal length of the first lens 11 is f11, the focal length of the second lens 12 is f12, the focal length of the third lens 13 is f13, and the focal length of the fourth lens 14 is f14; the focal length ratio of each lens in the first lens group 1 satisfies the following conditions: 0.058 < f1 / f11 < 0.086, and -0.662 < f1 / f12 < -0.441, and 0.427 < f1 / f13 < 0.641, and 0.29 < f1 / f14 < 0.435.

[0069] More specifically, in one embodiment, the first lens 11 is a convex-concave lens with positive refractive power, i.e., the object side surface of the first lens 11 is convex, and the image side surface is concave; the second lens 12 is a biconvex spherical lens with negative refractive power; the third lens 13 is a convex-concave spherical lens with positive refractive power; and the fourth lens 14 is a convex-concave spherical lens with positive refractive power; and the focal length ratio of each lens in the first lens group 1 is as follows: f1 / f11 = 0.07; f1 / f12 = -0.53; f1 / f13 = 0.51; and f1 / f14 = 0.35.

[0070] More specifically, in this embodiment, the focal length values of the first lens group 1 and each lens in the first lens group 1 are as follows: f1 = 72.435; f11 = 1048.4; f12 = -136.8; f13 = 141.3; and f14 = 208.2.

[0071] In particular, the second lens group 2 comprises, sequentially arranged from the object side to the image side, a fifth lens 21 with negative refractive power, a sixth lens 22 with negative refractive power, a seventh lens 23 with positive refractive power, and an eighth lens 24 with negative refractive power; the fifth lens 21, the sixth lens 22, and the seventh lens 23 are glass spherical lenses, and the eighth lens 24 is a glass aspherical lens; the sixth lens 22 and the seventh lens 23 are cemented together; the focal length of the fifth lens 21 is f21, the focal length of the sixth lens 22 is f22, the focal length of the seventh lens 23 is f23, and the focal length of the eighth lens is f24; the focal length ratio of each lens in the second lens group 2 satisfies the following conditions: 0.372 < f2 / f21 < 0.558, and 0.082 < f2 / f22 < 0.123, and -0.11 < f2 / f23 < -0.073, and 0.219 < f2 / f24 < 0.328.

[0072] More specifically, in this embodiment, the fifth lens 21 is a convex-concave lens with negative focal power, i.e. the object side surface of the fifth lens 21 is convex and the image side surface is concave, the sixth lens 22 is a double-concave spherical lens with negative focal power, the seventh lens 23 is a convex-concave spherical lens, i.e. the object side surface of the seventh lens 23 is convex and the image side surface is concave, and the eighth lens 24 is a concave-convex aspherical lens, i.e. the object side surface of the eighth lens 24 is concave and the image side surface is convex. The ratio of the focal length of the second lens group 2 to the focal length of each lens in the second lens group 2 is as follows: f2 / f21=0.45; f2 / f22=0.10; f2 / f23=-0.09; and f2 / f24=0.26.

[0073] More specifically, in this embodiment, the focal length of the second lens group 2 and the focal length of each lens in the second lens group 2 are as follows: f2=-12.498; f21=-28.0; f22=-126.9; f23=142.5; and f24=-47.64.

[0074] Specifically, the third lens group 3 includes, in order from the object side to the image side, a ninth lens 31 with positive focal power and a tenth lens 32 with positive focal power. The ninth lens 31 is a glass aspherical lens and the tenth lens 32 is a glass spherical lens. The focal length of the ninth lens 31 is f31 and the focal length of the tenth lens 32 is f32. The ratio of the focal length of the third lens group 3 to the focal length of each lens in the third lens group 3 satisfies the following conditions: 0.243

[0075] More specifically, in this embodiment, the ninth lens 31 is a convex-concave aspherical lens with positive focal power, i.e. the object side surface of the ninth lens 31 is convex and the image side surface is concave, and the tenth lens 32 is a double-convex lens with positive focal power. The ratio of the focal length of the third lens group 3 to the focal length of each lens in the third lens group 3 is as follows: f3 / f31=0.29; and f3 / f32=0.74.

[0076] More specifically, in this embodiment, the focal length of the third lens group 3 and the focal length of each lens in the third lens group 3 are as follows: f3=29.128; f31=99.7; and f32=39.2.

[0077] Specifically, the fourth lens group 4 includes an eleventh lens 41 with negative focal power. The eleventh lens 41 is a glass aspherical lens. More specifically, in this embodiment, the eleventh lens 41 is a concave-convex lens, i.e. the object side surface of the eleventh lens 41 is concave and the image side surface is convex, and the focal length of the eleventh lens 41 is f41=-65.96.

[0078] Specifically, the fifth lens group 5 includes, sequentially from the object side to the image side, a twelfth lens 51 with positive refractive power, a thirteenth lens 52 with negative refractive power, and a fourteenth lens 53 with positive refractive power; the twelfth lens 51 and the thirteenth lens 52 are glass spherical lenses, and the fourteenth lens 53 is a glass aspherical lens; the twelfth lens 51 and the thirteenth lens 52 are cemented together; the focal length of the twelfth lens 51 is f51, the focal length of the thirteenth lens 52 is f52, and the focal length of the fourteenth lens 53 is f53; and the ratio of the focal length of each lens in the fifth lens group 5 satisfies the following conditions: 0.015 < f5 / f51 < 0.023, -0.72 < f5 / f52 < -0.480, and 1.008 < f5 / f53 < 1.511.

[0079] More specifically, in this embodiment, the twelfth lens 51 is a biconvex lens with positive refractive power, the thirteenth lens 52 is a biconcave lens with negative refractive power, and the fourteenth lens 53 is a biconvex lens with positive refractive power; and the ratio of the focal length of each lens in the fifth lens group 5 is as follows: f5 / f51 = 0.02; f5 / f52 = -0.58; and f5 / f53 = 1.21.

[0080] More specifically, in this embodiment, the fifth lens group 5 and the focal length of each lens in the fifth lens group 5 are as follows: f5 = 27.845; f51 = 1528.2; f52 = -48.3; and f53 = 23.

[0081] Specifically, the sixth lens group 6 includes a fifteenth lens 61 with negative refractive power, and the fifteenth lens 61 is a glass spherical lens. More specifically, in this embodiment, the fifteenth lens 61 is a meniscus lens, and the focal length of the fifteenth lens 61 is f61 = -49.815.

[0082] Specifically, in order to ensure the stability of the zoom optical system under temperature changes, the first lens 11, the second lens 12, the third lens 13, the fourth lens 14, the fifth lens 21, the sixth lens 22, the seventh lens 23, the tenth lens 32, the twelfth lens 51, the thirteenth lens 52, and the fifteenth lens 61 are all glass spherical lenses. Since glass lenses are not easily affected by thermal expansion and contraction, they can well resist the problem of lens deformation caused by heat, maintain high precision of the lens for a long time, and reduce costs under the premise of ensuring image quality and reliability, have low assembly sensitivity, and improve the yield of finished products.

[0083] In the embodiment, the eighth lens 24, the ninth lens 31, the eleventh lens 41, and the fourteenth lens 53 are all glass aspherical lenses. The aspherical lens has the characteristic that the curvature continuously changes from the center of the lens to the periphery of the lens. Unlike the spherical lens with constant curvature from the center of the lens to the periphery of the lens, the aspherical lens has better curvature radius characteristics, has the advantages of improving the distortion aberration and the astigmatism aberration, and can eliminate the aberration as much as possible during imaging, thereby improving the imaging quality of the lens. The lens made of glass can reduce the influence of temperature on the optical performance of the lens.

[0084] Further, in order to reduce the loss of light energy, increase the imaging clarity, protect the scale surface, and further optimize the processing flow to meet the design requirements, in the embodiment, the first lens 11 and the second lens 12 are glued and connected to form a first glued lens, the sixth lens 22 and the seventh lens 23 are glued and connected to form a second glued lens, and the twelfth lens 51 and the thirteenth lens 52 are glued and connected to form a third glued lens. In this way, the glued parts are reasonably used, and the optical components improve the image quality of the optical system.

[0085] In this way, by reasonably allocating the focal power of the lenses, adjusting the shape and material of the glass, effectively eliminating the chromatic aberration and secondary spectrum, and mutually compensating and offsetting the spherical aberration, coma, and astigmatism on each lens, the clear imaging effect is achieved, and the optimal correction of high-order aberration and chromatic aberration is realized.

[0086] Specifically, in a specific embodiment, the refractive index, the curvature radius, and the thickness interval of the lens are as shown in the following table:

[0087]

[0088] Further, in the embodiment, the aspherical surface shape of the aspherical lens satisfies the following conditions:

[0089]

[0090] wherein c is the curvature corresponding to the radius, y is the radial coordinate (which has the same unit as the lens length), k is the conic quadratic curve coefficient (when the k coefficient is less than -1, the surface curve is a hyperbola, when the k coefficient is equal to -1, it is a parabola, when the k coefficient is between -1 and 0, it is an ellipse, when the k coefficient is equal to 0, it is a circle, and when the k coefficient is greater than 0, it is a flat circle), A, B, C, D, E, F, and G are high-order aspherical coefficients (please refer to Table 2 below), and the shape and size of the aspherical surface of the lens can be set through the above parameters.

[0091] Table 2 Conic coefficients and aspheric coefficients corresponding to aspheric lenses

[0092]

[0093] Specifically, the zoom optical system further comprises a diaphragm 8, which is located between the second lens group 2 and the third lens group 3; that is, the diaphragm 8 is located between the seventh lens 23 and the eighth lens 24. In the embodiment, the zoom optical system satisfies the following condition: 0.435 < L / TTL < 0.532; wherein L is the distance from the diaphragm 8 to the image plane 7 on the optical axis, and TTL is the total optical length of the zoom optical system. It should be noted that the total optical length is the distance from the object-side central vertex of the first lens 11 to the image plane 7. In a specific embodiment, L = 73.7 mm.

[0094] In the embodiment, the ratio of the distance from the diaphragm 8 to the image plane 7 to the total optical length of the zoom optical system is: L / TTL = 0.48.

[0095] Specifically, in the embodiment, the zoom optical system further comprises a filter, which is located between the sixth lens group 6 and the image plane 7. The filter is used to filter out unnecessary band light and stray light, so as to reduce light noise and reduce the difficulty of subsequent photoelectric module processing part. The filter can also be used to adjust the color degree of the object image during final imaging, thereby improving the imaging quality.

[0096] Specifically, the image plane 7 can be understood as the surface of the photosensitive chip facing the object side, that is, the surface of the CCD or CMOS image sensor. It can be understood that the light carrying the object information can pass through the first lens group 1, the second lens group 2, the diaphragm 8, the third lens group 3, the fourth lens group 4, the fifth lens group 5, the sixth lens group 6, the filter and finally image on the image plane 7.

[0097] Specifically, the zoom optical system satisfies the following condition: 0.313 < øL11 / TTL < 0.383; wherein øL11 is the effective clear aperture of the first lens 1111, and TTL is the total optical length of the zoom optical system.

[0098] In the embodiment, the ratio of the effective clear aperture of the first lens 1111 to the total optical length of the zoom optical system is: øL11 / TTL = 0.35.

[0099] Specifically, the zoom optical system satisfies the following condition: 0.197 < øL12 / TTL < 0.240; wherein øL12 is the effective clear aperture of the second lens 1112, and TTL is the total optical length of the zoom optical system. ​TTL is the total track length of the zoom optical system.

[0100] In the embodiment, the ratio of the moving amount of the second lens group 2 when the zoom optical system moves from the wide angle end to the telephoto end to the total track length of the zoom optical system is: TTL = 0.218.

[0101] Specifically, the zoom optical system satisfies the following condition: 0.123 TTL < 0.151; wherein, TTL is the total track length of the zoom optical system.

[0102] In the embodiment, the ratio of the moving amount of the third lens group 3 when the zoom optical system moves from the wide angle end to the telephoto end to the total track length of the zoom optical system is: TTL = 0.137.

[0103] Specifically, the embodiment sets the size of the image surface 7 to be φ9.4mm, and achieves the following performance parameters:

[0104] The wide angle end focal length fw = 13.58mm, the telephoto end focal length ft = 214.97mm; the wide angle end aperture number = 1.08, the telephoto end aperture number = 4.7; the optical distortion range is between 3.59% and 1.26%; the total track length of the zoom lens TTL = 152.4mm.

[0105] Table 3: Zoom data of the zoom optical system at the wide angle end, the intermediate magnification position, and the telephoto end, respectively

[0106]

[0107] Table 4: Focal length / aperture values of a specific embodiment of the zoom optical system lens at the wide angle end, the intermediate magnification position, and the telephoto end, respectively

[0108]

[0109] In the embodiment, please refer to Figures 1 to 3 Fig. 1 is a structural schematic diagram of the zoom optical system at the wide angle end, the intermediate magnification position, and the telephoto end, respectively; wherein the intermediate magnification can be understood as the position schematic diagram of each lens group in the zoom optical system when the zoom optical system is between the wide angle end and the telephoto end.

[0110] Figures 4 to 5 The figures respectively show the longitudinal aberration, field curvature and distortion of the zoom optical system at the wide-angle end, wherein S and T respectively represent the aberration corresponding to the sagittal image plane and the tangential image plane.

[0111] Please refer to Figures 6 to 7 The figures respectively show the longitudinal aberration, field curvature and distortion of the zoom optical system at the wide-angle end, wherein S and T respectively represent the aberration corresponding to the sagittal image plane and the tangential image plane.

[0112] Please refer to Figures 8 to 9 The figures respectively show the longitudinal aberration, field curvature and distortion of the zoom optical system at the wide-angle end, wherein S and T respectively represent the aberration corresponding to the sagittal image plane and the tangential image plane.

[0113] From the above figures, it can be seen that the spherical aberration, field curvature and distortion of the zoom optical system in the present embodiment can be well corrected at the intermediate magnification, wide-angle end and telephoto end.

[0114] From the above figures, it can be seen that the spherical aberration, field curvature and distortion of the zoom optical system in the present embodiment can be well corrected at the intermediate magnification, wide-angle end and telephoto end.

[0115] In summary, the zoom optical system of the present application adopts a six-group structure of "positive-negative-positive-negative-positive-negative", and the focal length changes with the corresponding movement of the second lens group 2 and the fourth lens group 4. The fourth lens group 4 is used for focusing, and the focal length can change from <13.58mm at the wide-angle end to >214.97mm at the telephoto end. The optical distortion at the wide-angle end and the telephoto end is between 3.59% and 1.26%, which has the effects of wide angle, small distortion and large zoom.

[0116] The distance between the first lens group 1 and the image plane 7 is fixed, and the distance between the first lens group 1 and the image plane 7 is less than 152.4mm.

[0117] In addition, the present application also provides a camera device, which comprises the zoom optical system of the above technical solution. Since the camera device comprises the zoom optical system, the specific structure of the zoom optical system is referred to the above embodiments. Since the zoom optical system of the present camera device adopts all the technical solutions of the above embodiments, it at least has all the beneficial effects brought by the technical solutions of the above embodiments, which will not be repeated here.

[0118] The above merely describes optional embodiments of the present application, and does not limit the patent scope of the present application. Any equivalent structural changes made according to the content of the present application specification and drawings, or direct / indirect application in other related technical fields are included in the patent protection scope of the present application.

Claims

1. A zoom optical system characterized in that, The zoom optical system has an object side and an image side arranged oppositely along an optical axis direction, and comprises: a lens barrel; and a plurality of lens groups arranged in the lens barrel in sequence from the object side to the image side, including a first lens group with positive refractive power, a second lens group with negative refractive power, a third lens group with positive refractive power, a fourth lens group with negative refractive power, a fifth lens group with positive refractive power, a sixth lens group with negative refractive power, and an image surface, wherein the second lens group and the fourth lens group are movably arranged along the extension direction of the optical axis to zoom the zoom optical system, the fifth lens group is moved along the optical axis direction to focus the zoom optical system, and the image surface has a diameter of 9.4 mm; wherein the focal length of the zoom optical system at the wide-angle end is fw, the focal length of the first lens group is f1, the focal length of the second lens group is f2, the focal length of the third lens group is f3, the focal length of the fourth lens group is f4, the focal length of the fifth lens group is f5, the focal length of the sixth lens group is f6, and the zoom optical system satisfies the following conditions: 0.163 < fw / f1 < 0.221, and -1.278 < fw / f2 < -0.945, and 0.405 < fw / f3 < 0.548, and -0.242 < fw / f4 < -0.179, and 0.424 < fw / f5 < 0.574, and -0.321 < fw / f6 < -0.

237.

2. The zoom optical system according to claim 1, characterized by The first lens group comprises, in sequence from the object side to the image side, a first lens with positive refractive power, a second lens with negative refractive power, a third lens with positive refractive power, and a fourth lens with positive refractive power; The first lens, the second lens, the third lens, and the fourth lens are all glass spherical lenses; The first lens and the second lens are cemented together; The focal length of the first lens is f11, the focal length of the second lens is f12, the focal length of the third lens is f13, and the focal length of the fourth lens is f14, and the lenses in the first lens group satisfy the following conditions: 0.058 < f1 / f11 < 0.086, and -0.662 < f1 / f12 < -0.441, and 0.427 < f1 / f13 < 0.641, and 0.29 < f1 / f14 < 0.

435.

3. The zoom optical system according to claim 1, wherein The second lens group comprises, in sequence from the object side to the image side, a fifth lens with negative refractive power, a sixth lens with negative refractive power, a seventh lens with positive refractive power, and an eighth lens with negative refractive power; The fifth lens, the sixth lens, and the seventh lens are glass spherical lenses, and the eighth lens is a glass aspherical lens; The sixth lens and the seventh lens are cemented together; The focal length of the fifth lens is f21, the focal length of the sixth lens is f22, the focal length of the seventh lens is f23, and the focal length of the eighth lens is f24, and the lenses in the second lens group satisfy the following conditions: 0.372 < f2 / f21 < 0.558, and 0.082 < f2 / f22 < 0.123, and -0.11 < f2 / f23 < -0.073, and 0.219 < f2 / f24 < 0.

328.

4. The zoom optical system according to claim 1, characterized by The third lens group comprises, sequentially from the object side to the image side, a ninth lens having positive refractive power, a tenth lens having positive refractive power; The ninth lens is a glass aspheric lens, and the tenth lens is a glass spherical lens; The focal length of the ninth lens is f31, the focal length of the tenth lens is f32, and each lens in the third lens group satisfies the following condition: 0.243 < f3 / f31 < 0.365, and 0.619 < f3 / f32 < 0.

928.

5. The zoom optical system according to claim 1, wherein The fourth lens group comprises an eleventh lens having negative refractive power, the eleventh lens being a glass aspheric lens; and / or, The sixth lens group comprises a fifteenth lens having negative refractive power, the fifteenth lens being a glass spherical lens.

6. The zoom optical system according to claim 1, characterized by The fifth lens group comprises, sequentially from the object side to the image side, a twelfth lens having positive refractive power, a thirteenth lens having negative refractive power, and a fourteenth lens having positive refractive power; The twelfth lens and the thirteenth lens are glass spherical lenses, and the fourteenth lens is a glass aspheric lens; The twelfth lens and the thirteenth lens are cemented together; The focal length of the twelfth lens is f51, the focal length of the thirteenth lens is f52, and the focal length of the fourteenth lens is f53, and each lens in the fifth lens group satisfies the following condition: 0.015 < f5 / f51 < 0.023, and -0.72 < f5 / f52 < -0.480, and 1.008 < f5 / f53 < 1.

511.

7. The zoom optical system according to claim 1, wherein The zoom optical system satisfies the following condition: 0.313 < øL11 / TTL < 0.383; Wherein, øL11 is the effective clear aperture of the first lens, and TTL is the total optical length of the zoom optical system.

8. The zoom optical system according to claim 1, characterized by The zoom optical system satisfies the following condition: ； wherein TTL is an overall optical length of the zoom optical system, and TTL is an overall optical length of the zoom optical system, and 9. The zoom optical system according to claim 1, wherein The zoom optical system further comprises a diaphragm, the diaphragm being located between the second lens group and the third lens group; Wherein, the distance from the diaphragm to the image plane of the zoom optical system on the optical axis is L, the total optical length of the zoom optical system is TTL, and in the zoom optical system: 0.435 < L / TTL < 0.

532.

10. An image pickup apparatus characterized by comprising: A zoom optical system as claimed in any one of claims 1 to 9.

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