Zoom lens

Abstract

The application discloses a zoom lens, which comprises, in order from the object side to the image side along the optical axis, 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 positive refractive power, wherein the fourth lens group comprises a cemented lens, and a fifth lens group with positive refractive power; wherein the first lens group and the third lens group are fixed groups; the second lens group and the fourth lens group are zoom groups; the fifth lens group is a focusing group; and the zoom lens satisfies: -0.8≤FB / FG4≤-0.1, wherein FB is the total effective focal length of the cemented lens in the fourth lens group, and FG4 is the effective focal length of the fourth lens group.

Description

Technical Field

[0001] This application relates to the field of optical components, and more specifically, to a zoom lens. Background Technology

[0002] With the rapid development of technology, zoom lenses are widely used in fields such as security monitoring and intelligent transportation. At the same time, users are also placing higher demands on zoom lenses, such as:

[0003] 1. To meet the need for providing full-color images at night, a low difference requirement is put forward for the consistency of the visible and infrared image planes of the zoom lens;

[0004] 2. To improve the accuracy of identification and judgment, low distortion is required for zoom lenses;

[0005] 3. To meet the demands for clear and high-resolution images, a large aperture is required for zoom lenses;

[0006] 4. To meet the demand for low cost, miniaturization of zoom lenses has been required;

[0007] 5. In order to meet the requirements of higher production yield, it is proposed to reduce the design tolerance sensitivity of zoom lenses.

[0008] However, existing zoom lenses have many problems, such as: 1) Existing zoom lenses have difficulty in taking infrared light into account to correct off-axis chromatic aberration; 2) Existing zoom lenses have difficulty in balancing long back focal length and high zoom ratio; 3) Existing zoom lenses have difficulty in maintaining low distortion during zooming; 4) Existing zoom lenses have difficulty in balancing large aperture and small aperture; 5) Existing zoom lenses have poor consistency between visible and infrared image height; 6) Existing zoom lenses have sensitive group tolerances and have difficulty in ensuring high resolution throughout the zoom range.

[0009] Therefore, designing a zoom lens that can achieve at least one of the following characteristics—continuous zoom, independent imaging of visible and infrared light, low tolerance sensitivity, and excellent image quality—while satisfying the requirements of miniaturization, is one of the pressing problems that many lens designers need to solve. Summary of the Invention

[0010] This application provides a zoom lens comprising, along the optical axis from the object side to the image side, the following in sequence: a first lens group with positive optical power, which is a fixed group; a second lens group with negative optical power, which is a zoom group; a third lens group with positive optical power, which is a fixed group; a fourth lens group with positive optical power, which is a zoom group and includes a cemented lens; and a fifth lens group with positive optical power, which is a focusing group; wherein the zoom lens satisfies: -0.8≤FB / FG4≤-0.1, where FB is the total effective focal length of the cemented lens in the fourth lens group, and FG4 is the effective focal length of the fourth lens group.

[0011] In one embodiment, the first lens group includes, sequentially from the object side to the image side along the optical axis: a first lens having positive optical power; a second lens having negative optical power; and a third lens having positive optical power.

[0012] In one embodiment, the second lens group includes, sequentially from the object side to the image side along the optical axis: a fourth lens having negative optical power; a fifth lens having negative optical power; and a sixth lens having positive optical power.

[0013] In one embodiment, the third lens group includes, sequentially from the object side to the image side along the optical axis: a seventh lens having positive optical power; and an eighth lens having negative optical power.

[0014] In one embodiment, the fourth lens group includes, sequentially from the object side to the image side along the optical axis: a ninth lens having positive optical power; a tenth lens having negative optical power; an eleventh lens having positive optical power; a twelfth lens having negative optical power; and a thirteenth lens having positive optical power.

[0015] In one embodiment, the fifth lens group includes, sequentially from the object side to the image side along the optical axis: a fourteenth lens with positive optical power; a fifteenth lens with negative optical power; and a sixteenth lens with positive optical power.

[0016] In one embodiment, the object-side surfaces of the first lens, the second lens, and the third lens are all convex, and the image-side surfaces are all concave.

[0017] In one embodiment, the second and third lenses in the first lens group form a cemented doublet lens.

[0018] In one embodiment, the object-side surface of the fourth lens is concave, and the image-side surface is concave; the object-side surface of the fifth lens is concave, and the image-side surface is concave; and the object-side surface of the sixth lens is convex, and the image-side surface is concave.

[0019] In one embodiment, in the second lens group, the fifth lens and the sixth lens constitute a cemented doublet lens.

[0020] In one embodiment, the object-side surface of the seventh lens is convex, and the image-side surface is convex; while the object-side surface of the eighth lens is concave, and the image-side surface is convex.

[0021] In one embodiment, the object-side surface of the ninth lens is convex, and the image-side surface is convex; the image-side surface of the tenth lens is concave; the object-side surface of the eleventh lens is convex, and the image-side surface is convex; the object-side surface of the twelfth lens is concave, and the image-side surface is concave; and the object-side surface of the thirteenth lens is convex, and the image-side surface is convex.

[0022] In one embodiment, in the fourth lens group, the tenth lens, the eleventh lens, and the twelfth lens form a cemented triplet lens, or the tenth lens, the eleventh lens, the twelfth lens, and the thirteenth lens form a cemented quadruplet lens.

[0023] In one embodiment, the object-side surface of the fourteenth lens is convex, and the image-side surface is convex; the object-side surface of the fifteenth lens is concave, and the image-side surface is concave; and the object-side surface of the sixteenth lens is convex, and the image-side surface is convex.

[0024] In one implementation, the zoom lens satisfies: -1.6≤FG2 / Fw≤-1.1, where FG2 is the effective focal length of the second lens group and Fw is the total effective focal length of the zoom lens when it is in wide-angle mode.

[0025] In one implementation, the zoom lens satisfies: 4.1≤FG3 / Fw≤5.5, where FG3 is the effective focal length of the third lens group and Fw is the total effective focal length of the zoom lens when it is in wide-angle mode.

[0026] In one embodiment, the zoom lens satisfies: 3.1≤FG4 / Fw≤4.0, where FG4 is the effective focal length of the fourth lens group and Fw is the total effective focal length of the zoom lens when it is in wide-angle mode.

[0027] In one implementation, the zoom lens satisfies: 2.3≤FG5 / Fw≤3.4, where FG5 is the effective focal length of the fifth lens group and Fw is the total effective focal length of the zoom lens when it is in wide-angle mode.

[0028] In one implementation, the zoom lens satisfies: 4.1 < Ft / Fw ≤ 4.5, where Ft is the total effective focal length of the zoom lens when it is in telephoto mode, and Fw is the total effective focal length of the zoom lens when it is in wide-angle mode.

[0029] In one embodiment, the zoom lens further includes a beam splitter prism located between the fifth lens group and the imaging plane of the zoom lens; the zoom lens satisfies: 0.1 < L / Fw ≤ 0.4, where L is the distance on the optical axis between the image side of the beam splitter prism and the imaging plane of the zoom lens, and Fw is the total effective focal length of the zoom lens when it is in wide-angle mode.

[0030] In one implementation, the zoom lens satisfies: 1.5 < BFL / Fw ≤ 1.8, where BFL is the distance on the optical axis between the image side of the lens closest to the image side and the imaging plane of the zoom lens, and Fw is the total effective focal length of the zoom lens when it is in wide-angle mode.

[0031] In one implementation, the zoom lens satisfies: 2.0 ≤ TTL / Ft < 3.0, where TTL is the distance on the optical axis from the object side of the lens closest to the object side to the imaging plane of the zoom lens, and Ft is the total effective focal length of the zoom lens when it is in telephoto mode.

[0032] In one embodiment, the zoom lens satisfies: 9.0 ≤ TTL / H < 9.6, where TTL is the distance on the optical axis from the object side of the lens closest to the object side to the imaging plane of the zoom lens, and H is the diagonal length of the effective pixel area on the imaging plane of the zoom lens.

[0033] In one implementation, the zoom lens satisfies: 0.2≤Dmax / TTL<0.5, where Dmax is the maximum effective aperture of the zoom lens during zooming, and TTL is the distance on the optical axis from the object side of the lens closest to the object side to the imaging plane of the zoom lens.

[0034] In one implementation, the zoom lens satisfies: 1.0 ≤ 2Fw × tan(FOVw / 2) / H ≤ 1.3, where Fw is the total effective focal length of the zoom lens in wide-angle mode, FOVw is the maximum field of view of the zoom lens in wide-angle mode, and H is the diagonal length of the effective pixel area on the imaging plane of the zoom lens.

[0035] In one embodiment, the zoom lens satisfies: 5.2≤FG1 / Fw≤5.7, where FG1 is the effective focal length of the first lens group and Fw is the total effective focal length of the zoom lens when it is in wide-angle mode.

[0036] In one embodiment, the zoom lens satisfies: 0.1≤D1 / TTL≤0.4, where D1 is the distance the second lens group moves from the wide-angle state to the telephoto state, and TTL is the distance on the optical axis from the object side of the lens closest to the object side to the imaging plane of the zoom lens.

[0037] In one embodiment, the zoom lens satisfies: 2.5≤D1 / D2≤5.5, where D1 is the distance the second lens group moves from the wide-angle state to the telephoto state, and D2 is the distance the fourth lens group moves from the wide-angle state to the telephoto state.

[0038] In an exemplary embodiment of this application, a five-group, three-motor architecture of fixed + zoom + fixed + zoom + focus is adopted. The fourth lens group includes a cemented lens. By reasonably setting the optical power of the first to fifth lens groups and the ratio of the total effective focal length of the cemented lens in the fourth lens group to the effective focal length of the fourth lens group, the zoom lens provided by this application can have at least one of the following beneficial effects: continuous zoom, independent imaging of visible light and infrared light, miniaturization, and low distortion. Attached Figure Description

[0039] Other features, objects, and advantages of this application will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0040] Figure 1 This is a schematic diagram of the zoom lens in wide-angle mode according to Embodiment 1 of this application;

[0041] Figure 2 This is a distortion image of the zoom lens in wide-angle mode according to Embodiment 1 of this application;

[0042] Figure 3 This is a schematic diagram of the zoom lens in telephoto mode according to Embodiment 1 of this application;

[0043] Figure 4 This is a distortion image of the zoom lens in telephoto mode according to Embodiment 1 of this application;

[0044] Figure 5 This is a schematic diagram of the zoom lens in wide-angle mode according to Embodiment 2 of this application;

[0045] Figure 6 This is a distortion image of the zoom lens in wide-angle mode according to Embodiment 2 of this application;

[0046] Figure 7 This is a schematic diagram of the zoom lens in telephoto mode according to Embodiment 2 of this application;

[0047] Figure 8 This is a distortion image of the zoom lens in telephoto mode according to Embodiment 2 of this application;

[0048] Figure 9 This is a schematic diagram of the zoom lens in wide-angle mode according to Embodiment 3 of this application;

[0049] Figure 10This is a distortion image of the zoom lens in wide-angle mode according to Embodiment 3 of this application;

[0050] Figure 11 This is a schematic diagram of the zoom lens in telephoto mode according to Embodiment 3 of this application;

[0051] Figure 12 This is a distortion image of the zoom lens in telephoto mode according to Embodiment 3 of this application;

[0052] Figure 13 This is a schematic diagram of the zoom lens in wide-angle mode according to Embodiment 4 of this application;

[0053] Figure 14 This is a distortion image of the zoom lens in wide-angle mode according to Embodiment 4 of this application;

[0054] Figure 15 This is a structural schematic diagram of the zoom lens in telephoto mode according to Embodiment 4 of this application; and

[0055] Figure 16 This is a distortion image of the zoom lens in telephoto mode according to Embodiment 4 of this application. Detailed Implementation

[0056] To better understand this application, various aspects of this application will be described in more detail with reference to the accompanying drawings. It should be understood that these detailed descriptions are merely illustrative of exemplary embodiments of this application and are not intended to limit the scope of this application in any way. Throughout the specification, the same reference numerals refer to the same elements. The expression "and / or" includes any and all combinations of one or more of the associated listed items.

[0057] It should be noted that in this specification, the terms "first," "second," "third," etc., are used only to distinguish one feature from another and do not imply any limitation on the features. Therefore, without departing from the teachings of this application, the first lens discussed below may also be referred to as the second lens or the third lens.

[0058] In the accompanying drawings, the thickness, size, and shape of the lenses have been slightly exaggerated for ease of illustration. Specifically, the shapes of the spherical or aspherical surfaces shown in the drawings are illustrated by way of example. That is, the shapes of the spherical or aspherical surfaces are not limited to those shown in the drawings. The drawings are for illustrative purposes only and are not strictly to scale.

[0059] In this article, the paraxial region refers to the region near the optical axis. If the lens surface is convex and the location of the convexity is not defined, it means that the lens surface is convex at least in the paraxial region; if the lens surface is concave and the location of the concaveness is not defined, it means that the lens surface is concave at least in the paraxial region. The surface of each lens closest to the subject is called the object-side surface of the lens, and the surface of each lens closest to the imaging plane is called the image-side surface of the lens.

[0060] It should also be understood that the terms "comprising," "including," "having," "containing," and / or "comprising," when used in this specification, indicate the presence of the stated features, elements, and / or components, but do not exclude the presence or addition of one or more other features, elements, components, and / or combinations thereof. Furthermore, when expressions such as "at least one of..." appear after a list of listed features, they modify the entire list of features, not individual elements in the list. Additionally, when describing embodiments of this application, the word "may" is used to mean "one or more embodiments of this application." And the term "exemplary" is intended to refer to an example or illustration.

[0061] Unless otherwise specified, all terms used herein (including technical and scientific terms) shall have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains. It should also be understood that terms (e.g., those defined in common dictionaries) shall be interpreted as having the meaning consistent with their meaning in the context of the relevant art and shall not be interpreted in an idealized or overly formalized sense, unless expressly so specified herein.

[0062] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0063] The features, principles and other aspects of this application are described in detail below.

[0064] A zoom lens according to an exemplary embodiment of this application may include five lens groups with optical power: a first lens group with positive optical power, a second lens group with negative optical power, a third lens group with positive optical power, a fourth lens group with positive optical power, and a fifth lens group with positive optical power. These five lens groups are arranged sequentially along the optical axis from the object side to the image side. The first and third lens groups are fixed groups, and their positions relative to the imaging plane of the zoom lens are fixed. The second and fourth lens groups are zoom groups, and they can move along the optical axis between the object side and the image side, respectively, to enable continuous zooming of the zoom lens. The fifth lens group is a focusing group, which makes a non-linear movement along the optical axis corresponding to the movement of the second and fourth lens groups to achieve a compensation effect.

[0065] In an exemplary embodiment, the first lens group includes at least two lenses with positive optical power and at least one lens with negative optical power; the second lens group includes at least one lens with positive optical power and at least two lenses with negative optical power; the third lens group includes at least one lens with positive optical power and at least one lens with negative optical power; the fourth lens group includes at least three lenses with positive optical power and at least two lenses with negative optical power; and the fifth lens group includes at least two lenses with positive optical power and at least one lens with negative optical power.

[0066] In an exemplary embodiment, the first lens group may include three lenses with optical power: a first lens, a second lens, and a third lens. The second lens group may include three lenses with optical power: a fourth lens, a fifth lens, and a sixth lens. The third lens group may include two lenses with optical power: a seventh lens and an eighth lens. The fourth lens group may include five lenses with optical power: a ninth lens, a tenth lens, an eleventh lens, a twelfth lens, and a thirteenth lens. The fifth lens group may include three lenses with optical power: a fourteenth lens, a fifteenth lens, and a sixteenth lens. These sixteen lenses are arranged sequentially along the optical axis from the object side to the image side.

[0067] The zoom lens according to an exemplary embodiment of this application also includes a beam splitter prism located between the fifth lens group and the imaging plane of the zoom lens.

[0068] In an exemplary embodiment, the zoom lens according to this application further includes an aperture stop disposed between the third lens group and the fourth lens group, and more specifically, the aperture stop is disposed between the eighth lens and the ninth lens.

[0069] In an exemplary embodiment, the position of the second lens group along the optical axis is adjustable; that is, the second lens group can move from the image side to the object side or from the object side to the image side along the optical axis to enable continuous zooming of the zoom lens. Specifically, by changing the position of the second lens group on the optical axis, the zoom lens can switch from a wide-angle state to a telephoto state or vice versa, enabling continuous zooming. Exemplarily, the focal length of the zoom lens is adjusted by regulating the spacing between the third and fourth lenses on the optical axis, and / or the spacing between the sixth and seventh lenses on the optical axis, to achieve a better imaging position and enable continuous zooming, ensuring clear imaging at different distances from the subject.

[0070] In an exemplary embodiment, the position of the fourth lens group along the optical axis is adjustable; that is, the fourth lens group can move from the image side to the object side or from the object side to the image side along the optical axis to enable continuous zooming of the zoom lens. Specifically, by changing the position of the fourth lens group on the optical axis, the zoom lens can switch from a wide-angle state to a telephoto state or vice versa, enabling continuous zooming. For example, the focal length of the zoom lens can be adjusted by adjusting the spacing between the eighth and ninth lenses on the optical axis, and / or the spacing between the thirteenth and fourteenth lenses on the optical axis, to give the zoom lens an optimal imaging position, thereby achieving continuous zooming and ensuring clear imaging at different distances from the subject.

[0071] In an exemplary embodiment, the position of the fifth lens group along the optical axis is adjustable. For example, the fifth lens group can make a non-linear movement along the optical axis corresponding to the movement of the second and fourth lens groups to achieve a compensation effect, thereby stabilizing the image quality of the zoom lens during continuous zooming. Exemplarily, by adjusting the spacing between the thirteenth and fourteenth lenses on the optical axis, and / or the spacing between the sixteenth lens and the beam splitter on the optical axis, the zoom lens can be adjusted to have a better imaging position during zooming, ensuring clear imaging at different distances from the subject.

[0072] For example, the second lens group performs the primary zoom function and has a large range of motion, while the fourth lens group performs the secondary zoom function and maintains a stable focal length. By changing the position of the second lens group on the optical axis, the zoom lens can switch from wide-angle to telephoto mode or vice versa, enabling continuous zooming.

[0073] In an exemplary embodiment, the first lens group may have positive optical power. The first lens group may be a fixed group. The position of the first lens group along the optical axis may be fixed, that is, the position of the first lens group relative to the imaging plane is fixed. This arrangement of the first lens group is beneficial for converging light and reducing the aperture of the rear lens.

[0074] In an exemplary embodiment, a first lens group (fixed group) with positive optical power, in conjunction with a second lens group (zoom group) with negative optical power, constitutes a telephoto lens structure, which is beneficial for achieving a constant aperture throughout the zoom range. The first lens group has a smaller optical power, which is beneficial for correcting the secondary spectrum.

[0075] In an exemplary embodiment, the second lens group may have negative optical power. The second lens group may be a zoom group. The position of the second lens group along the optical axis is adjustable, that is, the second lens group can move along the optical axis from the image side to the object side or from the object side to the image side to achieve continuous zoom. This arrangement of the second lens group is advantageous for undertaking the main zoom function, has a large range of motion, and can realize continuous zoom of the zoom lens from wide-angle to telephoto or from telephoto to wide-angle.

[0076] In an exemplary embodiment, the third lens group may have positive optical power. The third lens group may be a fixed group. The position of the third lens group along the optical axis may be fixed, that is, the position of the third lens group relative to the imaging plane is fixed. This arrangement of the third lens group is beneficial for making the outgoing light rays smoother and reducing the generation of aberrations.

[0077] In an exemplary embodiment, the fourth lens group may have positive optical power. The fourth lens group may be a zoom group. The position of the fourth lens group along the optical axis is adjustable, that is, the fourth lens group can move along the optical axis from the image side to the object side or from the object side to the image side to achieve continuous zoom. This arrangement of the fourth lens group is beneficial for undertaking secondary zoom functions and maintaining a stable focal length.

[0078] In an exemplary embodiment, the fifth lens group may have positive optical power. The fifth lens group may be a focusing group. The fifth lens group may move non-linearly along the optical axis in accordance with the movements of the second and fourth lens groups to achieve a compensation effect, ensuring stable image quality of the zoom lens during continuous zooming. This arrangement of the fifth lens group facilitates focusing or adjusting the focus, achieving image plane correction, and ensuring that the image quality on the imaging plane of the zoom lens remains stable during zooming, enabling clear focusing from object distances of 2m to infinity.

[0079] In an exemplary embodiment, the first lens group may include three lenses with optical power: a first lens with positive optical power, a second lens with negative optical power, and a third lens with positive optical power. The first lens group adopts a positive-negative-positive configuration, which is beneficial for converging light rays to smoothly enter the optical system and reducing the aperture of the rear lens.

[0080] In an exemplary embodiment, the object-side surfaces of the first, second, and third lenses can be convex, and the image-side surfaces can be concave. Such surface configuration helps to reduce distortion.

[0081] In an exemplary embodiment, the second and third lenses may be cemented lenses. Using a set of cemented lenses helps reduce chromatic aberration and lowers the tolerance sensitivity of the first lens group.

[0082] In an exemplary embodiment, the second lens group may include three lenses with optical power: a fourth lens with negative optical power, a fifth lens with negative optical power, and a sixth lens with positive optical power. The fourth lens has a concave object-side surface and a concave image-side surface; the fifth lens has a concave object-side surface and a concave image-side surface; and the sixth lens has a convex object-side surface and a concave image-side surface. The second lens group has a large negative optical power and undertakes the main zoom function of the optical system; the fourth lens in the second lens group bears the main negative optical power, which is beneficial to improving the zoom efficiency of the lens; the combination of the above-mentioned lens optical power and shape in the second lens group helps to balance the spherical aberration introduced by the fourth lens.

[0083] In an exemplary embodiment, the fifth and sixth lenses may be cemented lenses. In the second lens group, the fourth lens is paired with a set of cemented lenses, which helps to balance the positional chromatic aberration of the second lens group and reduce the tolerance sensitivity of the motion group.

[0084] In an exemplary embodiment, the third lens group may include two lenses with optical power: a seventh lens with positive optical power and an eighth lens with negative optical power. The object-side surface of the seventh lens may be convex, and the image-side surface may also be convex. The object-side surface of the eighth lens may be concave, and the image-side surface may be convex. The third lens group, employing the combination of optical power and shape of the aforementioned lenses as an intermediate fixed group, facilitates adjustment of the light angle, ensuring a smooth transition of light to the rear optical system, and improving system resolution. Simultaneously, it allows for a reduction in the aperture of the rear lenses, thus lowering costs. The combination of positive and negative lenses in the third lens group facilitates mutual compensation of positive and negative spherical aberrations, further improving system resolution.

[0085] In an exemplary embodiment, the third lens group can be located relatively close to the aperture stop, with an overall positive optical power. By converging the light rays, the amount of light entering the aperture stop can be controlled, which is beneficial for the stability of the aperture throughout the zoom range and to achieve continuous changes in image brightness without abrupt changes.

[0086] In an exemplary embodiment, the fourth lens group may include five lenses with optical power: a ninth lens with positive optical power, a tenth lens with negative optical power, an eleventh lens with positive optical power, a twelfth lens with negative optical power, and a thirteenth lens with positive optical power. The object-side surface of the ninth lens may be convex, and the image-side surface may also be convex. The object-side surface of the tenth lens may be either convex or concave, and the image-side surface may be concave. The object-side surface of the eleventh lens may be convex, and the image-side surface may also be convex. The object-side surface of the twelfth lens may be concave, and the image-side surface may also be concave. The object-side surface of the thirteenth lens may be convex, and the image-side surface may also be convex. The fourth lens group performs a secondary zoom function of the zoom lens; the ninth lens in this group provides the primary positive optical power, which is beneficial for improving the zoom efficiency of the lens. The combination of optical power and shape of the lenses in the fourth lens group helps to balance the spherical aberration introduced by the ninth lens.

[0087] In an exemplary embodiment, the tenth lens, the eleventh lens, and the twelfth lens may be configured as a cemented triplet lens.

[0088] In an exemplary embodiment, the tenth lens, the eleventh lens, the twelfth lens, and the thirteenth lens can be configured as a four-colloidal lens.

[0089] In the fourth lens group, the ninth lens is paired with a cemented lens, which is equivalent to introducing an aspherical lens. This provides greater freedom, better balances the aberrations of the fourth lens group, reduces the tolerance sensitivity of the moving group, and corrects system aberrations, thus improving system resolution.

[0090] In this application, by setting a cemented lens, it is beneficial to control the direction of light, reduce the tolerance sensitivity of the zoom lens, and improve the production and assembly yield; at the same time, it can also effectively correct the system chromatic aberration, realize independent imaging of visible light and infrared light, and greatly improve the imaging quality.

[0091] In an exemplary embodiment, the fifth lens group may include three lenses with optical power: a fourteenth lens with positive optical power, a fifteenth lens with negative optical power, and a sixteenth lens with positive optical power. The fourteenth lens may have a convex object-side surface and a convex image-side surface. The fifteenth lens may have a concave object-side surface and a concave image-side surface. The sixteenth lens may have a convex object-side surface and a convex image-side surface. The fourteenth lens bears the majority of the positive optical power in this group, which is beneficial for improving lens focusing efficiency. The combination of optical power and shape of the lenses in this group helps to balance the spherical aberration introduced by the fourteenth lens. The fifteenth and sixteenth lenses use a combination of negative and positive lenses, and the curvature of the image-side surface of the fifteenth lens and the object-side surface of the sixteenth lens are similar, which can compensate for their off-axis aberrations and distortions, achieving the effect of a cemented lens. This helps to balance the positional chromatic aberration of the fifth lens group and reduce the tolerance sensitivity of the moving group.

[0092] In an exemplary embodiment, the fifteenth lens has a large negative optical power, making the entire system from the first lens to the fifteenth lens negative optical power. This, together with the last lens (i.e., the sixteenth lens) with positive optical power, forms a reverse telephoto architecture, shifting the image principal plane backward and increasing the back focal length of the optical system. The fifth lens group, acting as the focusing group, controls the movement of the focusing group during zooming, allowing for a return stroke. This significantly reduces the focusing distance in telephoto mode, greatly shortening the overall lens length and facilitating miniaturization.

[0093] This application, by reasonably setting the optical power of each lens group and the optical power and surface shape of each lens, is beneficial for the zoom lens to have a good ability to correct optical aberrations and chromatic aberrations at different distances from the subject. At the same time, it helps to reduce the tolerance sensitivity of the system and improve the uniformity of the image.

[0094] In an exemplary embodiment of this application, the zoom lens according to this application satisfies: 5.2≤FG1 / Fw≤5.7, where FG1 is the effective focal length of the first lens group, and Fw is the total effective focal length of the zoom lens in wide-angle mode. Satisfying 5.2≤FG1 / Fw≤5.7, by reasonably controlling the focal length value of the first lens group, is beneficial to achieving reasonable aberration distribution and high image quality.

[0095] In an exemplary embodiment of this application, the zoom lens according to this application satisfies: -1.6 ≤ FG2 / Fw ≤ -1.1, where FG2 is the effective focal length of the second lens group, and Fw is the total effective focal length of the zoom lens in wide-angle mode. Satisfying -1.6 ≤ FG2 / Fw ≤ -1.1, by reasonably controlling the focal length value of the second lens group, is beneficial to achieving reasonable aberration distribution and high image quality.

[0096] In an exemplary embodiment of this application, the zoom lens according to this application satisfies: 4.1≤FG3 / Fw≤5.5, where FG3 is the effective focal length of the third lens group, and Fw is the total effective focal length of the zoom lens when it is in wide-angle mode. Satisfying 4.1≤FG3 / Fw≤5.5, by reasonably controlling the focal length value of the third lens group, is beneficial to achieving reasonable aberration distribution and high image quality.

[0097] In an exemplary embodiment of this application, the zoom lens according to this application satisfies: 3.1≤FG4 / Fw≤4.0, where FG4 is the effective focal length of the fourth lens group, and Fw is the total effective focal length of the zoom lens in wide-angle mode. Satisfying 3.1≤FG4 / Fw≤4.0, by reasonably controlling the focal length value of the fourth lens group, is beneficial to achieving reasonable aberration distribution and high image quality.

[0098] In an exemplary embodiment of this application, the zoom lens according to this application satisfies: 2.3≤FG5 / Fw≤3.4, where FG5 is the effective focal length of the fifth lens group, and Fw is the total effective focal length of the zoom lens in wide-angle mode. Satisfying 2.3≤FG5 / Fw≤3.4, by reasonably controlling the focal length value of the fifth lens group, is beneficial to achieving reasonable aberration distribution and high image quality.

[0099] In an exemplary embodiment of this application, the zoom lens according to this application satisfies: 4.1 < Ft / Fw ≤ 4.5, where Ft is the total effective focal length of the zoom lens in telephoto mode, and Fw is the total effective focal length of the zoom lens in wide-angle mode. By satisfying 4.1 < Ft / Fw ≤ 4.5 and reasonably controlling the ratio of the focal length in telephoto mode to the focal length in wide-angle mode, the zoom ratio of the zoom lens reaches 4.28 or higher, which is beneficial for achieving a large zoom ratio and increasing the applicability of the zoom lens.

[0100] In an exemplary embodiment of this application, the zoom lens further includes a beam-splitting prism located between the fifth lens group and the imaging plane of the zoom lens; the zoom lens satisfies: 0.1 < L / Fw ≤ 0.4, where L is the distance on the optical axis between the image-side surface of the beam-splitting prism and the imaging plane of the zoom lens, and Fw is the total effective focal length of the zoom lens in wide-angle mode. Satisfying 0.1 < L / Fw ≤ 0.4 allows for reasonable control of the optical back focal length of the zoom lens, reducing the sensitivity of lens thickness and air gap value to MTF, improving production yield, and reducing production costs.

[0101] In an exemplary embodiment of this application, the zoom lens according to this application satisfies: 1.5 < BFL / Fw ≤ 1.8, where BFL is the distance on the optical axis between the image-side surface of the lens closest to the image side and the imaging plane of the zoom lens, and Fw is the total effective focal length of the zoom lens in wide-angle mode. Satisfying 1.5 < BFL / Fw ≤ 1.8 ensures a sufficiently long back focal length, which is beneficial for the placement of the optical prism and enables consistency between the visible and infrared paths.

[0102] In an exemplary embodiment of this application, the zoom lens according to this application satisfies: 2.0 ≤ TTL / Ft < 3.0, where TTL is the distance on the optical axis from the object side of the lens closest to the object side to the imaging plane of the zoom lens, and Ft is the total effective focal length of the zoom lens in telephoto mode. Satisfying 2.0 ≤ TTL / Ft < 3.0, while ensuring a certain total effective focal length in telephoto mode, controls the overall optical length of the system, making the overall optical length of the system smaller, which is beneficial for miniaturization.

[0103] In an exemplary embodiment of this application, the zoom lens according to this application satisfies: 9.0 ≤ TTL / H < 9.6, where TTL is the distance on the optical axis from the object side of the lens closest to the object side to the imaging plane of the zoom lens, and H is the diagonal length of the effective pixel area on the imaging plane of the zoom lens. Satisfying 9.0 ≤ TTL / H < 9.6, under a certain system image height, by controlling the overall optical length of the system, the overall optical length of the system is made smaller, which is beneficial for miniaturization.

[0104] For example, the distance TTL from the center of the object side of the first lens to the imaging surface of the zoom lens on the optical axis can satisfy TTL≤125mm.

[0105] In an exemplary embodiment of this application, the zoom lens according to this application satisfies: 0.2 ≤ Dmax / TTL < 0.5, where Dmax is the maximum effective aperture of the zoom lens during zooming, and TTL is the distance on the optical axis from the object side of the lens closest to the object side to the imaging plane of the zoom lens. Satisfying 0.2 ≤ Dmax / TTL < 0.5, within a given total system optical length, controls the maximum aperture during system zooming, resulting in a smaller maximum aperture, which is beneficial for miniaturization. For example, by limiting the aperture of the first lens group, the aperture of the largest lens in the first lens group is reduced, thereby reducing the effective aperture of the lens, reducing the material required for the zoom lens, and lowering the cost of the zoom lens.

[0106] In an exemplary embodiment of this application, the zoom lens according to this application satisfies: 1.0 ≤ 2Fw × tan(FOVw / 2) / H ≤ 1.3, where Fw is the total effective focal length of the zoom lens in wide-angle mode, FOVw is the maximum field of view of the zoom lens in wide-angle mode, and H is the diagonal length of the effective pixel area on the imaging plane of the zoom lens. By satisfying 1.0 ≤ 2Fw × tan(FOVw / 2) / H ≤ 1.3 and controlling the relationship between the focal length and field of view of the system in wide-angle mode, the ratio of the actual image height to the theoretical image height is relatively small, which is beneficial for achieving low distortion.

[0107] In an exemplary embodiment of this application, the zoom lens according to this application satisfies: -0.8 ≤ FB / FG4 ≤ -0.1, where FB is the total effective focal length of the cemented lenses in the fourth lens group, and FG4 is the effective focal length of the fourth lens group. Satisfying -0.8 ≤ FB / FG4 ≤ -0.1, by reasonably allocating the focal length ratio between the cemented lenses and the fourth lens group, allows for the correction of the overall chromatic aberration of the fourth lens group, which helps to reduce the tolerance sensitivity of the fourth lens group.

[0108] In an exemplary embodiment of this application, the zoom lens according to this application satisfies: 0.1 ≤ D1 / TTL ≤ 0.4, where D1 is the movement distance of the second lens group from the wide-angle state to the telephoto state, and TTL is the distance on the optical axis from the object side of the lens closest to the object side to the imaging plane of the zoom lens. Satisfying 0.1 ≤ D1 / TTL ≤ 0.4, by controlling the movement distance of the second lens group, increases the zoom range of the optical system, which is beneficial for achieving a large zoom ratio.

[0109] In an exemplary embodiment of this application, the zoom lens according to this application satisfies: 2.5 ≤ D1 / D2 ≤ 5.5, where D1 is the distance the second lens group moves from a wide-angle state to a telephoto state, and D2 is the distance the fourth lens group moves from a wide-angle state to a telephoto state. By satisfying 2.5 ≤ D1 / D2 ≤ 5.5 and selecting an appropriate ratio between the moving distances of the second and fourth lens groups, the zoom range of the zoom lens is increased, thus expanding its applicability.

[0110] The zoom lens according to this application consists of five lens groups with optical powers of positive, negative, positive, positive, and positive, and an aperture stop. By moving the zoom group and the focus group, the system zoom ratio can reach 4.28 or higher.

[0111] In the exemplary embodiment, the first to the sixteenth lenses are all glass spherical lenses. By using glass spherical lenses, this application helps to reduce the processing difficulty of the lenses; at the same time, through material matching, a heat-free design is achieved.

[0112] In an exemplary embodiment, the zoom lens may further include a filter for correcting color deviation and / or a protective glass for protecting the photosensitive element located on the imaging surface. This application proposes a zoom lens that, while satisfying the requirements of miniaturization, excellent image quality, large aperture, independent imaging of visible and infrared light, and stable optical performance under different usage environments, also achieves a large field of view and low cost. The zoom lens according to the above embodiments of this application can employ multiple lens elements, such as the sixteen elements mentioned above. By rationally allocating the optical power, surface shape, center thickness of each lens, and on-axis spacing between lenses, incident light can be effectively converged, the overall optical length of the imaging lens can be reduced, and the manufacturability of the imaging lens can be improved, making the zoom lens more conducive to manufacturing.

[0113] However, those skilled in the art will understand that the number of lenses constituting the zoom lens can be changed without departing from the technical solutions claimed in this application to obtain the various results and advantages described in this specification. For example, although sixteen lenses are described as an example in the embodiment, the zoom lens is not limited to including sixteen lenses. If desired, the zoom lens may also include other numbers of lenses.

[0114] The following describes in further detail, with reference to the accompanying drawings, specific embodiments of the zoom lens applicable to the above-described embodiments.

[0115] Example 1

[0116] The following is for reference Figures 1 to 4 The zoom lens 100 according to Embodiment 1 of this application is described. Figure 1This is a schematic diagram of the zoom lens 100 in wide-angle mode according to Embodiment 1 of this application. Figure 3 This is a schematic diagram of the zoom lens 100 in telephoto mode according to Embodiment 1 of this application.

[0117] like Figure 1 and Figure 3 As shown, the zoom lens 100 includes, from the object side to the image side, the following components in sequence: a first lens group G1 with positive optical power, a second lens group G2 with negative optical power, a third lens group G3 with positive optical power, a fourth lens group G4 with positive optical power, a fifth lens group G5 with positive optical power, a beam splitter G6, and an imaging plane IMA.

[0118] The first lens group G1 includes a first lens L1, a second lens L2, and a third lens L3. The first lens L1 has positive optical power, with its object-side surface S1 being convex and its image-side surface S2 being concave. The second lens L2 has negative optical power, with its object-side surface S3 being convex and its image-side surface S4 being concave. The third lens L3 has positive optical power, with its object-side surface S4 being convex and its image-side surface S5 being concave. The second lens L2 and the third lens L3 are cemented together to form a cemented lens.

[0119] The second lens group G2 includes a fourth lens L4, a fifth lens L5, and a sixth lens L6. The fourth lens L4 can have negative optical power, with its object-side surface S6 being concave and its image-side surface S7 being concave. The fifth lens L5 can have negative refractive power, with its object-side surface S8 being concave and its image-side surface S9 being concave. The sixth lens L6 can have positive refractive power, with its object-side surface S9 being convex and its image-side surface S10 being concave. The fifth lens L5 and the sixth lens L6 are cemented together to form a cemented lens.

[0120] The third lens group G3 includes a seventh lens L7 and an eighth lens L8. The seventh lens L7 can have positive refractive power, with its object-side surface S11 being convex and its image-side surface S12 being convex. The eighth lens L8 can have negative refractive power, with its object-side surface S13 being concave and its image-side surface S14 being convex.

[0121] The fourth lens group G4 includes the ninth lens L9, the tenth lens L10, the eleventh lens L11, the twelfth lens L12, and the thirteenth lens L13. The ninth lens L9 has positive optical power, with its object-side surface S16 and image-side surface S17 being convex. The tenth lens L10 has negative optical power, with its object-side surface S18 and image-side surface S19 being concave. The eleventh lens L11 has positive optical power, with its object-side surface S19 and image-side surface S20 being convex. The twelfth lens L12 has negative optical power, with its object-side surface S20 and image-side surface S21 being concave. The thirteenth lens L13 has positive optical power, with its object-side surface S22 and image-side surface S23 being convex. The tenth lens L10, the eleventh lens L11, and the twelfth lens L12 are cemented together to form a cemented lens.

[0122] The aperture STO can be set between the third lens group G3 and the fourth lens group G4. More specifically, the aperture STO can be set between the eighth lens L8 and the ninth lens L9.

[0123] The fifth lens group G5 includes the fourteenth lens L14, the fifteenth lens L15, and the sixteenth lens L16. The fourteenth lens L14 has positive optical power, with both its object-side surface S24 and image-side surface S25 being convex. The fifteenth lens L15 can have negative optical power, with both its object-side surface S26 and image-side surface S27 being concave. The sixteenth lens L16 has positive optical power, with both its object-side surface S28 and image-side surface S29 being convex.

[0124] The beam splitter G6 has an object-side surface S30 and an image-side surface S31. Light from the object passes through each surface in sequence (i.e., passes through the object-side surface S1 of the first lens L1 in sequence to the image-side surface S31 of the beam splitter G6) and is finally imaged on the imaging surface IMA. An image sensing chip may be provided at the imaging surface.

[0125] Table 1 shows the basic parameters of the zoom lens 100 of Embodiment 1, where the units for radius of curvature and thickness / distance are millimeters (mm).

[0126]

[0127]

[0128] Table 1

[0129] In this embodiment, by changing the positions of the second lens group G2, the fourth lens group G4, and the fifth lens group G5 on the optical axis, the total effective focal length of the zoom lens 100 can be changed as the distance from the subject changes, thereby achieving continuous zoom of the zoom lens 100.

[0130] Table 2 shows the air gaps on the optical axis of the first and second lens groups (T1), the second and third lens groups (T2), the third and fourth lens groups (T3), the fourth and fifth lens groups (T4), and the fifth lens group and beam splitter (T5) of the zoom lens 100 in Embodiment 1 when it is in wide-angle and telephoto modes. Table 2 also shows the total effective focal length F, total optical length TTL, and aperture value Fno of the zoom lens 100. F and Fno change as the zoom lens 100 switches from wide-angle to telephoto mode or vice versa, while TTL remains constant. All values ​​for F, TTL, T1, T2, T3, T4, and T5 are in millimeters (mm).

[0131] Wide-angle state Telephoto mode F(mm) 14 60 Fno 1.6 1.9 TTL(mm) 120 120 T1(mm) 1.48 30.49 T2(mm) 30.73 1.72 T3 (mm) 11.12 1.10 T4 (mm) 0.18 8.35 T5 (mm) 0.30 2.15

[0132] Table 2

[0133] Figure 2 and Figure 4 Distortion diagrams are shown for the zoom lens 100 in wide-angle and telephoto modes, respectively. According to... Figure 2 and Figure 4 It can be seen that the zoom lens 100 given in Example 1 can achieve good imaging quality at different focal lengths.

[0134] Example 2

[0135] The following is for reference Figures 5 to 8 The zoom lens 200 according to Embodiment 2 of this application is described. Figure 5 This is a schematic diagram of the zoom lens 200 in wide-angle mode according to Embodiment 2 of this application. Figure 7 This is a schematic diagram of the zoom lens 200 in telephoto mode according to Embodiment 2 of this application.

[0136] In this embodiment and the following embodiments, for the sake of brevity, the omitted parts are similar to the description in Embodiment 1.

[0137] like Figure 5 and Figure 7 As shown, the zoom lens 200 of Embodiment 2 has the same number of lenses and optical power as the zoom lens 100 of Embodiment 1. The difference is that the object side surface S18 of the tenth lens L10 of the zoom lens 200 of Embodiment 2 is convex, and the tenth lens L10, the eleventh lens L11, the twelfth lens L12 and the thirteenth lens L13 are cemented together to form a cemented lens.

[0138] Table 3 shows the basic parameters of the zoom lens 200 of Embodiment 2, where the units for radius of curvature and thickness / distance are millimeters (mm). Table 4 shows the air gaps on the optical axis of the first and second lens groups (T1), the second and third lens groups (T2), the third and fourth lens groups (T3), the fourth and fifth lens groups (T4), the fifth lens group and the beam splitter (T5), the total effective focal length F, the total optical length TTL, and the aperture value Fno of the zoom lens 200 when the zoom lens 200 is in wide-angle and telephoto states, respectively. The units for F, TTL, T1, T2, T3, T4, and T5 are millimeters (mm).

[0139]

[0140] Table 3

[0141]

[0142]

[0143] Table 4

[0144] Figure 6 and Figure 8 The distortion diagrams for zoom lens 200 in wide-angle and telephoto modes are shown respectively. According to... Figure 6 and Figure 8 It can be seen that the zoom lens 200 given in Example 2 can achieve good imaging quality at different focal lengths.

[0145] Example 3

[0146] The following is for reference Figures 9 to 12 The zoom lens 300 according to Embodiment 3 of this application is described. Figure 9 This is a schematic diagram of the zoom lens 300 in wide-angle mode according to Embodiment 3 of this application. Figure 11 This is a schematic diagram of the zoom lens 300 in telephoto mode according to Embodiment 3 of this application.

[0147] like Figure 9 and Figure 11 As shown, the zoom lens 300 of Embodiment 3 has the same number of lenses and optical power as the zoom lens 100 of Embodiment 1. The difference is that the object side S18 of the tenth lens L10 of the zoom lens 300 of Embodiment 3 is convex, and the tenth lens L10, the eleventh lens L11, the twelfth lens L12 and the thirteenth lens L13 are cemented together to form a cemented lens.

[0148] Table 5 shows the basic parameters of the zoom lens 300 of Embodiment 3, where the units for radius of curvature and thickness / distance are millimeters (mm). Table 6 shows the air gaps on the optical axis of the first and second lens groups (T1), the second and third lens groups (T2), the third and fourth lens groups (T3), the fourth and fifth lens groups (T4), the fifth lens group and the beam splitter (T5), the total effective focal length F, the total optical length TTL, and the aperture value Fno of the zoom lens 300 when it is in wide-angle and telephoto states, respectively. The units for F, TTL, T1, T2, T3, T4, and T5 are millimeters (mm).

[0149]

[0150]

[0151] Table 5

[0152] Wide-angle state Telephoto mode F(mm) 14 60 Fno 1.6 1.9 TTL(mm) 120 120 T1(mm) 2.04 33.04 T2(mm) 32.94 1.93 T3 (mm) 8.48 1.10 T4 (mm) 1.67 7.60 T5 (mm) 0.30 1.75

[0153] Table 6

[0154] Figure 10 and Figure 12 The distortion diagrams for zoom lens 300 in wide-angle and telephoto modes are shown respectively. According to... Figure 10 and Figure 12 It can be seen that the zoom lens 300 given in Example 3 can achieve good imaging quality at different focal lengths.

[0155] Example 4

[0156] The following is for reference Figures 13 to 16 The zoom lens 400 according to Embodiment 4 of this application is described. Figure 13 This is a schematic diagram of the zoom lens 400 in wide-angle mode according to Embodiment 4 of this application. Figure 15 This is a structural schematic diagram of the zoom lens 400 in telephoto mode according to Embodiment 4 of this application.

[0157] like Figure 13 and Figure 15 As shown, the zoom lens 400 of Embodiment 4 has the same number of lenses and optical power as the zoom lens 100 of Embodiment 1. The difference is that the object side surface S18 of the tenth lens L10 of the zoom lens 400 of Embodiment 4 is convex, and the tenth lens L10, the eleventh lens L11, the twelfth lens L12 and the thirteenth lens L13 are cemented together to form a cemented lens.

[0158] Table 7 shows the basic parameters of the zoom lens 400 of Embodiment 4, where the units for radius of curvature and thickness / distance are millimeters (mm). Table 8 shows the air gaps on the optical axis of the first and second lens groups (T1), the second and third lens groups (T2), the third and fourth lens groups (T3), the fourth and fifth lens groups (T4), the fifth lens group and the beam splitter (T5), the total effective focal length F, the total optical length TTL, and the aperture value Fno of the zoom lens 400 when it is in wide-angle and telephoto states, respectively. The units for F, TTL, T1, T2, T3, T4, and T5 are millimeters (mm).

[0159]

[0160] Table 7

[0161]

[0162]

[0163] Table 8

[0164] Figure 14 and Figure 16 The distortion diagrams for zoom lens 400 in wide-angle and telephoto modes are shown respectively. According to... Figure 14 and Figure 16 It can be seen that the zoom lens 400 given in Example 4 can achieve good imaging quality at different focal lengths.

[0165] In summary, Examples 1 to 4 satisfy the relationships shown in Table 9.

[0166] Conditional / Example 1 2 3 4 5.2≤FG1 / Fw≤5.7 5.354 5.469 5.478 5.533 -1.6≤FG2 / Fw≤-1.1 -1.340 -1.455 -1.435 -1.466 4.1≤FG3 / Fw≤5.5 4.351 5.360 4.980 5.321 3.1≤FG4 / Fw≤4.0 3.332 3.645 3.725 3.663 2.3≤FG5 / Fw≤3.4 3.159 2.531 2.564 2.557 4.1 < Ft / Fw ≤ 4.5 4.286 4.286 4.286 4.286 0.1 < L / Fw ≤ 0.4 0.229 0.243 0.243 0.243 1.5 < BFL / Fw ≤ 1.8 1.671 1.686 1.686 1.686 2.0 ≤ TTL / Ft < 3.0 2.000 2.000 2.000 2.000 9.0 ≤ TTL / H < 9.6 9.375 9.375 9.375 9.375 0.2 ≤ Dmax / TTL < 0.5 0.364 0.371 0.372 0.370 1.0≤2Fw×tan(FOVw / 2) / H≤1.3 1.115 1.115 1.115 1.115 -0.8≤FB / FG4≤-0.1 -0.340 -0.735 -0.724 -0.739 0.1 ≤ D1 / TTL ≤ 0.4 0.242 0.260 0.258 0.263 2.5 ≤ D1 / D2 ≤ 5.5 2.895 4.531 4.201 4.603

[0167] Table 9

[0168] This application also provides an imaging device, whose electronic photosensitive element can be a photocoupled device (CCD) or a complementary metal oxide semiconductor device (CMOS). The imaging device can be a stand-alone imaging device such as a machine vision system, or an imaging module integrated into a mobile electronic device such as a machine vision system. The imaging device is equipped with the zoom lens described above.

[0169] The above description is merely a preferred embodiment of this application and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of the invention involved in this application is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the inventive concept. For example, technical solutions formed by substituting the above features with (but not limited to) technical features with similar functions disclosed in this application.

Claims

1. A zoom lens, characterized in that, Along the optical axis from the object side to the image side, the following are included in sequence: A first lens group having positive optical power, wherein the first lens group is a fixed group; A second lens group with negative optical power, the second lens group being a zoom group; A third lens group with positive optical power, wherein the third lens group is a fixed group; A fourth lens group having positive optical power, the fourth lens group being a zoom group, comprising a cemented lens; and A fifth lens group with positive optical power, wherein the fifth lens group is a focusing group; in, The first lens group comprises, along the optical axis from the object side to the image side, a first lens having positive optical power, a second lens having negative optical power, and a third lens having positive optical power. The second lens group comprises, along the optical axis from the object side to the image side, a fourth lens having negative optical power, a fifth lens having negative optical power, and a sixth lens having positive optical power. The third lens group includes, along the optical axis from the object side to the image side, a seventh lens with positive optical power and an eighth lens with negative optical power. The fourth lens group includes, in sequence along the optical axis from the object side to the image side: a ninth lens with positive optical power, a tenth lens with negative optical power, an eleventh lens with positive optical power, a twelfth lens with negative optical power, and a thirteenth lens with positive optical power. The fifth lens group includes, along the optical axis from the object side to the image side, a fourteenth lens with positive optical power, a fifteenth lens with negative optical power, and a sixteenth lens with positive optical power. The zoom lens has sixteen lenses with optical power. The zoom lens satisfies: -0.8≤FB / FG4≤-0.1, where FB is the total effective focal length of the cemented lens in the fourth lens group, and FG4 is the effective focal length of the fourth lens group.

2. The zoom lens according to claim 1, characterized in that, The object-side surfaces of the first lens, the second lens, and the third lens are all convex, and the image-side surfaces are all concave.

3. The zoom lens according to claim 1, characterized in that, In the first lens group, the second lens and the third lens together form a cemented doublet lens.

4. The zoom lens according to claim 1, characterized in that, In the second lens group, the fifth lens and the sixth lens form a cemented doublet lens.

5. The zoom lens according to claim 1, characterized in that, In the fourth lens group, the tenth lens, the eleventh lens, and the twelfth lens form a cemented triplet lens, or the tenth lens, the eleventh lens, the twelfth lens, and the thirteenth lens form a cemented quadruplet lens.

6. The zoom lens according to any one of claims 1-5, characterized in that, The zoom lens satisfies: -1.6≤FG2 / Fw≤-1.1, where FG2 is the effective focal length of the second lens group and Fw is the total effective focal length of the zoom lens when it is in wide-angle mode.

7. The zoom lens according to any one of claims 1-5, characterized in that, The zoom lens satisfies: 4.1≤FG3 / Fw≤5.5, where FG3 is the effective focal length of the third lens group and Fw is the total effective focal length of the zoom lens when it is in wide-angle mode.

8. The zoom lens according to any one of claims 1-5, characterized in that, The zoom lens satisfies: 3.1≤FG4 / Fw≤4.0, where FG4 is the effective focal length of the fourth lens group and Fw is the total effective focal length of the zoom lens when it is in wide-angle mode.

9. The zoom lens according to any one of claims 1-5, characterized in that, The zoom lens satisfies: 2.3≤FG5 / Fw≤3.4, where FG5 is the effective focal length of the fifth lens group and Fw is the total effective focal length of the zoom lens when it is in wide-angle mode.

10. The zoom lens according to any one of claims 1-5, characterized in that, The zoom lens satisfies: 4.1 < Ft / Fw ≤ 4.5, where Ft is the total effective focal length of the zoom lens when it is in telephoto mode, and Fw is the total effective focal length of the zoom lens when it is in wide-angle mode.

11. The zoom lens according to any one of claims 1-5, characterized in that, The zoom lens also includes a beam splitter prism located between the fifth lens group and the imaging plane of the zoom lens; The zoom lens satisfies: 0.1 < L / Fw ≤ 0.4, where L is the distance between the image-side surface of the beam splitter and the imaging surface of the zoom lens on the optical axis, and Fw is the total effective focal length of the zoom lens when it is in wide-angle mode.

12. The zoom lens according to any one of claims 1-5, characterized in that, The zoom lens satisfies: 1.5 < BFL / Fw ≤ 1.8, where BFL is the distance between the image side of the lens closest to the image side and the imaging plane of the zoom lens on the optical axis, and Fw is the total effective focal length of the zoom lens when it is in wide-angle mode.

13. The zoom lens according to any one of claims 1-5, characterized in that, The zoom lens satisfies: 2.0≤TTL / Ft<3.0, where TTL is the distance from the object side of the lens closest to the object side to the imaging plane of the zoom lens on the optical axis, and Ft is the total effective focal length of the zoom lens when it is in telephoto mode.

14. The zoom lens according to any one of claims 1-5, characterized in that, The zoom lens satisfies: 9.0≤TTL / H<9.6, where TTL is the distance from the object side of the lens closest to the object side to the imaging surface of the zoom lens on the optical axis, and H is the diagonal length of the effective pixel area on the imaging surface of the zoom lens.

15. The zoom lens according to any one of claims 1-5, characterized in that, The zoom lens satisfies the following condition: 0.2 ≤ Dmax / TTL < 0.5, where Dmax is the maximum effective light-passing aperture of the zoom lens during the zoom process, and TTL is the distance on the optical axis from the object side of the lens closest to the object side to the imaging plane of the zoom lens.

16. The zoom lens according to any one of claims 1-5, characterized in that, The zoom lens satisfies: 1.0≤2Fw×tan(FOVw / 2) / H≤1.3, where Fw is the total effective focal length of the zoom lens in wide-angle mode, FOVw is the maximum field of view of the zoom lens in wide-angle mode, and H is the diagonal length of the effective pixel area on the imaging plane of the zoom lens.

17. The zoom lens according to any one of claims 1-5, characterized in that, The zoom lens satisfies: 5.2≤FG1 / Fw≤5.7, where FG1 is the effective focal length of the first lens group and Fw is the total effective focal length of the zoom lens when it is in wide-angle mode.

18. The zoom lens according to any one of claims 1-5, characterized in that, The zoom lens satisfies: 0.1≤D1 / TTL≤0.4, where D1 is the distance the second lens group moves from the wide-angle state to the telephoto state, and TTL is the distance from the object side of the lens closest to the object side in the zoom lens to the imaging plane of the zoom lens on the optical axis.

19. The zoom lens according to any one of claims 1-5, characterized in that, The zoom lens satisfies: 2.5 ≤ D1 / D2 ≤ 5.5, where, D1 is the distance the second lens group moves from the wide-angle state to the telephoto state, and D2 is the distance the fourth lens group moves from the wide-angle state to the telephoto state.

20. The zoom lens according to claim 1, characterized in that, The zoom lens satisfies any one of the following conditions: 5.354≤FG1 / Fw≤5.533 -1.466≤FG2 / Fw≤-1.340, 4.351≤FG3 / Fw≤5.360, 3.332≤FG4 / Fw≤3.725 2.531≤FG5 / Fw≤3.159, 4.286≤Ft / Fw≤4.5 4.1 < Ft / Fw ≤ 4.286 0.229≤L / Fw≤0.243, 1.671≤BFL / Fw≤1.686 9.375≤TTL / H<9.6, 9.0≤TTL / H≤9.375 0.364≤Dmax / TTL≤0.372 1.115≤2Fw×tan(FOVw / 2) / H≤1.3, 1.0≤2Fw×tan(FOVw / 2) / H≤1.115, -0.739≤FB / FG4≤-0.340, 0.242≤D1 / TTL≤0.263 2.895≤D1 / D2≤4.603, Wherein, FG1 is the effective focal length of the first lens group, Fw is the total effective focal length of the zoom lens in wide-angle mode, FG2 is the effective focal length of the second lens group, FG3 is the effective focal length of the third lens group, FG5 is the effective focal length of the fifth lens group, Ft is the total effective focal length of the zoom lens in telephoto mode, and the zoom lens also includes a beam splitter prism located between the fifth lens group and the imaging plane of the zoom lens, L is the distance on the optical axis between the image side of the beam splitter prism and the imaging plane of the zoom lens, and BFL is the focal length of the zoom lens closest to the image side. The distance between the image-side surface of the lens and the imaging plane of the zoom lens on the optical axis; TTL is the distance between the object-side surface of the lens closest to the object side in the zoom lens and the imaging plane of the zoom lens on the optical axis; H is the diagonal length of the effective pixel area on the imaging plane of the zoom lens; Dmax is the maximum effective light-passing aperture of the zoom lens during zooming; FOVw is the maximum field of view of the zoom lens when it is in wide-angle mode; D1 is the distance the second lens group moves from wide-angle mode to telephoto mode; and D2 is the distance the fourth lens group moves from wide-angle mode to telephoto mode.

Images