Zoom lens
Through the combination of two-component structure and the negative-positive power of 11 lenses and combined with the glued lens design, the existing zoom lens has solved the problems of small aperture and large chromatic aberration, and achieved miniaturized, high-resolution and high-temperature adaptability of zoom lenses, suitable for high-pixel and large-aperture imaging in the security field.
Patent Information
- Application Number
- CN202422436539.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-10
- Publication Date
- 2025-07-22
- Estimated Expiration
- 2034-10-10
AI Technical Summary
The existing two-group ultra-wide-angle zoom lens has a small aperture and a large color difference, which cannot meet the environmental needs of darker light and high color restoration. At the same time, it is costly and cannot adapt to large temperature changes.
A zoom lens with a two-component structure uses 11 lenses. Through the combination of negative-positive power, the light passes at a large angle. The power of the focus lens group and the zoom lens group are combined with the glued lens design to achieve miniaturization and high resolution, and adapt to temperature changes.
It realizes a miniaturized, high-resolution zoom lens, adapts to clear imaging within the temperature range of -40℃~80℃, with an aperture number of FNO between 1.6 and 3, and a maximum effective diameter of less than 25mm, meeting the imaging needs of high pixels and large apertures.
Smart Images
Figure CN223139946U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to a zoom lens and belongs to the technical field of optical devices. Background Art
[0002] In the security field, zoom lenses have been widely used due to their advantages such as long shooting distance and large shooting angle, but the high cost has limited the use scenarios of zoom lenses. With the development of technology, high pixels, large aperture, simple structure, good imaging effects in different temperature environments, and the ability to take into account larger target area imaging have become requirements for the new generation of security zoom lenses.
[0003] The disadvantages of the mainstream two-group ultra-wide-angle zoom lens on the market are small aperture and large chromatic aberration, which cannot meet the requirements of low-light environments and high color reproduction requirements. It is increasingly unable to meet market demand. The advantage of this application is that it can not only take into account good performance and miniaturization, but also adapt to large temperature changes. Utility Model Content
[0004] The utility model solves the technical problems existing in the prior art and provides a zoom lens.
[0005] A zoom lens comprises a focus lens group and a zoom lens group which are sequentially arranged from an object plane to an image plane along an optical axis, wherein the focus lens group comprises a first lens, a second lens, a third lens and a fourth lens which are sequentially arranged from the object plane to the image plane; and the zoom lens group comprises a fifth lens, a sixth lens, a seventh lens, an eighth lens, a ninth lens, a tenth lens and an eleventh lens which are sequentially arranged from the object plane to the image plane.
[0006] The second lens is glued to the third lens, the tenth lens is glued to the eleventh lens, the sixth lens is glued to the seventh lens to form a glued lens; the eighth lens is glued to the ninth lens to form a glued lens.
[0007] The object side surface of the fourth lens is concave, and the image side surface of the sixth lens is convex; the object side surface and the image side surface of the fifth lens are both convex; the focal length of the focus lens group is F1, the focal length of the zoom lens group is F2, and the focal length of the zoom lens at the wide-angle end is FW, satisfying: -2.45≤F1 / FW≤-1.4; 1.91≤F2 / FW≤3.35.
[0008] The total focal length of the fifth lens, the sixth lens, the seventh lens, the eighth lens and the ninth lens is F, the focal length of the zoom lens at the telephoto end is FT, and the relationship: 2.64≤F / FT≤2.94 is satisfied.
[0009] The effective focal length of the zoom lens is 4mm to 10mm, and the field of view angle ranges from 50° to 133°.
[0010] The advantages of the present utility model are that while taking into account good performance and miniaturization, it can also adapt to large temperature changes.
[0011] The present utility model adopts a two-component structure and uses 11 lenses. By setting the optical powers of the focusing lens group and the zoom lens group in a negative-positive combination. The optical power of the focusing lens group is negative, and the optical power of the zoom lens group is positive, ensuring that light can enter the subsequent structure through the focusing lens group at a large angle, and ensuring the ultra-wide-angle characteristics of the zoom lens. The fifth lens has a positive optical power, the sixth lens has a positive optical power, the seventh lens has a positive optical power, the eighth lens has a negative optical power, the ninth lens has a negative optical power, the tenth lens has a negative optical power, and the eleventh lens has a positive optical power. The optical total length of the zoom lens is less than 60 mm. Under a 1 / 1.8" target surface, the aperture number FNO satisfies 1.6 < FNO < 3, the maximum effective diameter < 25 mm, and the resolution is good in the 436 nm - 650 nm band. Thus, a zoom lens with small size, high resolution, and confocal at high and low temperatures is realized, meeting the use requirements of clear imaging under a 1 / 1.8" target surface. Brief Description of the Drawings
[0012] In order to more clearly illustrate the technical solutions in the embodiments of the present utility model or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present utility model. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings. As shown in the figures:
[0013] Figure 1 is the two-dimensional view of the wide-angle end of the present utility model.
[0014] Figure 2 is the two-dimensional view of the telephoto end of the embodiment of the present utility model.
[0015] Figure 3 is the optical distortion characteristic curve of the telephoto and short focal lengths of the present utility model, representing the astigmatism curve and distortion curve of the optical imaging system, which represents the meridional image plane curvature, sagittal image plane curvature, and distortion magnitude values corresponding to different image heights. The abscissa is the focus offset amount, the ordinate is the image height, and the solid and dashed lines represent the meridional and sagittal components of different image heights.
[0016] Figure 4 is the optical distortion characteristic curve of the telephoto and short focal lengths of the present utility model, representing the astigmatism curve and distortion curve of the optical imaging system, which represents the meridional image plane curvature, sagittal image plane curvature, and distortion magnitude values corresponding to different image heights. The abscissa is the distortion magnitude, and the ordinate is the image height.
[0017] Figure 5It is the optical distortion characteristic curves of the long focal length and short focal length of the present utility model, representing the astigmatism curve and distortion curve of the optical imaging system, which represent the meridional image plane curvature, sagittal image plane curvature and the distortion magnitude values corresponding to different image heights. The abscissa is the focus offset, and the ordinate is the image height. The solid line and the dashed line represent the meridional and sagittal components of different image heights.
[0018] Figure 6 It is the optical distortion characteristic curves of the long focal length and short focal length of the present utility model, representing the astigmatism curve and distortion curve of the optical imaging system, which represent the meridional image plane curvature, sagittal image plane curvature and the distortion magnitude values corresponding to different image heights. The abscissa is the distortion magnitude, and the ordinate is the image height. Specific embodiments
[0019] Next, the technical solutions in the embodiments of the present utility model will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without making creative efforts shall fall within the protection scope of the present utility model.
[0020] Embodiment 1: As Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 and Figure 6 shown, an optical zoom lens (2.5 - fold continuous visible light zoom lens) includes a first focusing lens group and a zoom lens group arranged in sequence along the optical axis from the object plane to the image plane. The focusing lens group and the zoom lens group move along the optical axis during zooming. The focusing lens group has a negative optical power, and the zoom lens group has a positive optical power.
[0021] The focusing lens group includes a first lens L1, a second lens L2, a third lens L3, and a fourth lens L4 arranged in sequence from the object plane to the image plane; the zoom lens group includes a fifth lens L5, a sixth lens L6, a seventh lens L7, an eighth lens L8, a ninth lens L9, a tenth lens L10, and an eleventh lens L11 arranged in sequence from the object plane to the image plane; the third lens L3, the fifth lens L5, the sixth lens L6, the seventh lens L7, and the eleventh lens L11 have positive optical powers; the first lens L1, the second lens L2, the fourth lens L4, the eighth lens L8, the ninth lens L9, and the tenth lens L10 have negative optical powers.
[0022] The second lens L2 and the third lens L3 are cemented together, the tenth lens L10 and the eleventh lens L11 are cemented together, and the cemented lens formed by cementing the sixth lens L6 and the seventh lens L7 together has a positive optical power; the cemented lens formed by cementing the eighth lens L8 and the ninth lens L9 together has a positive optical power.
[0023] The object side of the fourth lens is concave, and the image side of the sixth lens L6 is convex; the object side and the image side of the fifth lens L5 are both convex; the focal length of the focusing lens group is F1, the focal length of the zoom lens group is F2, and the focal length of the zoom lens at the wide-angle end is FW, satisfying: -2.45 ≤ F1 / FW ≤ -1.4; 1.91 ≤ F2 / FW ≤ 3.35.
[0024] For the fifth lens L5, the sixth lens L6 and the seventh lens L7, the total focal length of the eighth lens L8 and the ninth lens L9 is F, and the focal length of the zoom lens at the telephoto end is FT, satisfying:
[0025] 2.64 ≤ F / FT ≤ 2.94.
[0026] The effective focal length of the zoom lens is 4 mm to 10 mm, and the field of view angle range is 50° to 133°.
[0027] The aspherical surface of the lens satisfies the relationship:
[0028]
[0029] where x is the distance from the corresponding point on the aspherical surface to the plane tangent to the surface vertex, h is the distance from the corresponding point on the aspherical surface to the optical axis, c is the curvature of the aspherical surface vertex, k is the conic coefficient, and Ai is the coefficient corresponding to the i-th high-order term in the aspherical surface formula.
[0030] Example 2: As Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 and Figure 6 shown, an optical zoom lens (2.5x continuous visible light zoom lens) adopts a two-element structure, uses 11 lenses, and adopts a negative-positive combination method by setting the optical power of the focusing lens group and the zoom lens group. The optical power of the focusing lens group is negative, and the optical power of the zoom lens group is positive, ensuring that light can enter the subsequent structure through the focusing lens group at a large angle, and ensuring the ultra-wide-angle characteristics of the zoom lens. The fifth lens has a positive optical power, the sixth lens has a positive optical power, the seventh lens has a positive optical power, the eighth lens has a negative optical power, the ninth lens has a negative optical power, the tenth lens has a negative optical power, and the eleventh lens has a positive optical power. The optical total length of the zoom lens is less than 60 mm. Under the 1 / 1.8" target surface, the aperture number FNO satisfies 1.6 < FNO < 3, the maximum effective diameter < 25 mm, and the resolution is good in the 436 nm to 650 nm band, thus realizing a zoom lens with small size, high resolution, and confocal at high and low temperatures, meeting the use requirements of clear imaging under the 1 / 1.8" target surface.
[0031] Example 3: AsFigure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 and Figure 6 As shown in Figure 5 and Figure 6 , an optical zoom lens (2.5x continuous visible light zoom lens) has an effective focal length f` = 4 - 10 mm and a zoom ratio of 2.5x.
[0032] 1. The field of view angle range is 50° - 133°.
[0033] 2. The operating temperature is -40°C - 80°C.
[0034] 3. The volume of the optical system is less than 13 mm (width) × 13 mm (height) × 58 mm (length).
[0035] 4. Fno 1.6 - 3.
[0036] Table 1 Optical Parameters of Each Lens
[0037]
[0038]
[0039] Table 2
[0040] Surface serial number K A B C D E S6 -12.5275 -2.21041 0.000261 5.82E-07 -8.69E-08 7.60E-10 S7 -27.0269 -1.34546 0.000277 1.18E-06 -1.02E-07 8.33E-10 S9 12.86386 -2.82459 0.000128 3.20E-06 -6.86E-08 1.66E-09 S10 -55.6787 -8.70026 0.000176 3.84E-06 -6.27E-08 1.81E-09
[0041] In Table 2, K is the conic coefficient, and A, B, C, D, E are the coefficients of the high-order aspheric surface.
[0042] When the aspheric surface satisfies the above parameters, it also satisfies the following relational expressions:
[0043]
[0044] Among them, x is the distance from the corresponding point on the aspheric surface to the plane tangent to the surface vertex, h is the distance from the corresponding point on the aspheric surface to the optical axis, c is the curvature of the aspheric surface vertex, k is the conic coefficient, and Ai is the coefficient corresponding to the i-th high-order term in the aspheric surface formula.
[0045] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principles of the present invention shall be included in the protection scope of the present invention.
Claims
1. A zoom lens, characterized in that, It includes a focusing lens group and a zoom lens group arranged in sequence from the object plane to the image plane along the optical axis. The focusing lens group includes a first lens, a second lens, a third lens, and a fourth lens arranged in sequence from the object plane to the image plane; the zoom lens group includes a fifth lens, a sixth lens, a seventh lens, an eighth lens, a ninth lens, a tenth lens, and an eleventh lens arranged in sequence from the object plane to the image plane.
2. The zoom lens according to claim 1, wherein The second lens is cemented to the third lens, the tenth lens is cemented to the eleventh lens, and the sixth lens is cemented to the seventh lens to form a cemented lens; the eighth lens is cemented to the ninth lens to form a cemented lens.
3. A zoom lens according to claim 1, characterized in that, The object side surface of the fourth lens is concave, and the image side surface of the sixth lens is convex; the object side surface and the image side surface of the fifth lens are both convex; the focal length of the focusing lens group is F1, the focal length of the zoom lens group is F2, and the focal length of the zoom lens at the wide-angle end is FW, satisfying: -2.45 ≤ F1 / FW ≤ -1.4; 1.91 ≤ F2 / FW ≤ 3.
35.
4. A zoom lens according to claim 1, characterized in that, The total focal length of the fifth lens, the sixth lens, the seventh lens, the eighth lens, and the ninth lens is F, and the focal length of the zoom lens at the telephoto end is FT, satisfying: 2.64 ≤ F / FT ≤ 2.
94.
5. A zoom lens according to claim 1, characterized in that, The effective focal length of the zoom lens is 4 mm to 10 mm, and the field of view angle range is 50° to 133°.