Compact zoom optical system

Abstract

The utility model relates to a compact zoom optical system. The compact zoom optical system comprises a compensation group, a diaphragm, a zoom group and an imaging group which are sequentially arranged along an incident light path, the lenses with focal power of the compensation group are a meniscus positive lens G1, a meniscus negative lens G2, a meniscus negative lens G3 and a meniscus positive lens G4 in sequence; the lenses with focal power of the zoom group are a biconvex positive lens G5, a biconvex positive lens G6, a meniscus negative lens G7, a biconvex positive lens G8, a biconcave negative lens G9, a biconvex positive lens G10 and a meniscus negative lens G11 in sequence, the biconvex lens G6 and the meniscus lens G7 are bonded to form a first gluing group H1, the biconvex lens G8 and the biconcave lens G9 are bonded to form a second gluing group H2, and the biconvex lens G8 and the biconcave lens G9 are bonded to form a third gluing group H2. And the biconvex lens G10 and the meniscus lens G11 are bonded to form a third gluing group H3. The compact zoom optical system is compact in optical structure, has multi-point focal length, and is flexible in application range; in addition, high-resolution imaging and low distortion are achieved, it is ensured that clear images are obtained under different focal lengths within a certain range, and the monitoring and detection accuracy is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of photoelectricity, in particular to a compact zoom optical system. Background Art

[0002] With the continued development of my country's intelligent manufacturing industry and the rapid growth of high-tech manufacturing and strategic emerging industries, the laser cutting industry has also experienced rapid development in recent years, with a market size expected to reach US$6.9 billion by 2030. Secondly, with the advancement of computer intelligence and automation, the laser cutting industry has introduced intelligent machine vision technology into production, integrating advanced intelligent control systems, machine vision, and automated feeding devices, gradually replacing traditional processing technologies, thereby improving production accuracy and processing efficiency, reducing manual operations, and minimizing errors.

[0003] Secondly, with the increasing diversification of laser processing applications, machine vision systems are increasingly demanding higher precision, faster speeds, and better processing results. These systems must also be adaptable to diverse application scenarios and ensure clear images at a range of focal lengths. Therefore, designing a machine vision lens that achieves both high precision and multi-focality is crucial for the highly variable laser cutting industry. In the future, the laser cutting industry will enter a new era of intelligence, automation, and efficiency. Equipment will become even more intelligent, enabling automated production and remote monitoring. Laser cutting technology will continue to innovate, expanding its application areas. Utility Model Content

[0004] In view of this, an object of the present invention is to provide a compact zoom optical system with a compact optical structure and multiple focal lengths, so as to ensure that a clear image is obtained at different focal lengths within a certain range.

[0005] The utility model is implemented by the following scheme: a compact zoom optical system, comprising a compensation group, an aperture, a magnification group and an imaging group arranged in sequence along an incident light path; the lenses having optical focal power in the compensation group along the incident light path are sequentially a meniscus positive lens G1, a meniscus negative lens G2, a meniscus negative lens G3 and a meniscus positive lens G4; the lenses having optical focal power in the magnification group along the incident light path are sequentially a biconvex positive lens G5, a biconvex positive lens G6, a meniscus negative lens G7, a biconvex positive lens G8, a biconcave negative lens G9, a biconvex positive lens G10 and a meniscus negative lens G11, wherein the biconvex lens G6 and the meniscus lens G7 are bonded to form a first cemented group H1, the biconvex lens G8 and the biconcave lens G9 are bonded to form a second cemented group H2, and the biconvex lens G10 and the meniscus lens G11 are bonded to form a third cemented group H3.

[0006] Furthermore, in the compensation group, the air gap between the meniscus positive lens G1 and the meniscus negative lens G2 is 0.1 mm, the air gap between the meniscus negative lens G2 and the meniscus negative lens G3 is 3.71 mm, and the air gap between the meniscus negative lens G3 and the meniscus positive lens G4 is 4.03 mm.

[0007] Furthermore, the air gap between the biconvex positive lens G5 and the first cemented group H1 in the zoom group is 0.1 mm, the air gap between the first cemented group H1 and the second cemented group H2 is 0.1 mm, and the air gap between the second cemented group H2 and the third cemented group H3 is 0.8 mm.

[0008] Furthermore, the air gap between the compensation group and the aperture varies between 2.8-13.7 mm; the air gap between the aperture and the zoom group varies between 0.8-7.2 mm; and the air gap between the zoom group and the imaging group varies between 14.36-8.0 mm.

[0009] Furthermore, the refractive index of the meniscus positive lens G1 is n1 and the Abbe number is V1, which satisfy the relationship: 1.72<n1<1.85, 48<V1<60; the refractive index of the meniscus negative lens G2 is n2 and the Abbe number is V2, which satisfy the relationship: 1.85<n2<1.95, 33<V2<36; the refractive index of the meniscus negative lens G3 is n3 and the Abbe number is V3, which satisfy the relationship: 1.78<n3<1.89, 39<V3<44; the refractive index of the meniscus positive lens G4 is n4 and the Abbe number is V4, which satisfy the relationship: 2.05<n4<1.15, 17<V4<18; the refractive index of the biconvex positive lens G5 is n5 and the Abbe number is V5, which satisfy the relationship : 1.82<n5<1.85, 40<V5<45; the refractive index of the biconvex positive lens G6 is n6 and the Abbe number is V6, which satisfy the relationship: 1.49<n6<1.5, 74<V6<80; the refractive index of the meniscus negative lens G7 is n7 and the Abbe number is V7, which satisfy the relationship: 1.9<n7<1.92, 31<V7<34; the refractive index of the biconvex positive lens G8 is n8 and the Abbe number is V8, which satisfy the relationship: 1.92<n8<1.93, 20<V8<21; the refractive index of the biconcave negative lens G9 is n9 and the Abbe number is V9, which satisfy the relationship: 1.8<n9<1.81, 25<V9<26; the refractive index of the biconvex positive lens G10 is n 10 , Abbe number is V 10 , which satisfies the relationship: 1.58<n 10 <1.61、63<V 10 <69; the refractive index of the meniscus negative lens G11 is n 11 , Abbe number is V 11 , which satisfies the relationship: 1.83<n11 <1.86、23<V 11 <25.

[0010] Furthermore, all lenses are glass spherical lenses.

[0011] Furthermore, the imaging group includes a flat glass G12 and an imaging surface, and the air gap between the flat glass G12 and the imaging surface is 0.1 mm.

[0012] Compared with the existing technology, the present invention has the following beneficial effects: the present invention has a compact zoom optical system with a compact optical structure, multiple focal lengths, and a flexible application range; compared with fixed focal length lenses, the zoom optical system has more flexible usage characteristics, and can change the focal length within a certain range according to different industrial application scenarios to perform real-time fine adjustment of the image, meet various special needs, and improve the flexibility and application range of the equipment; it also has high-resolution imaging and low distortion, ensuring clear images at different focal lengths within a certain range, thereby improving the accuracy of monitoring and detection.

[0013] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below through specific embodiments and related drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a schematic diagram of the optical system of an embodiment of the utility model;

[0015] Figure 2 This is the MTF curve of the optical system at a focal length of 5.5mm according to the embodiment of the present invention;

[0016] Figure 3 This is an MTF curve diagram of the optical system at 8mm focal length according to an embodiment of the present invention;

[0017] Figure 4 This is an MTF curve diagram of the optical system at a focal length of 12mm according to an embodiment of the present invention;

[0018] Figure 5 This is a graph showing the field curvature and distortion of the optical system at a focal length of 5.5 mm according to an embodiment of the present invention;

[0019] Figure 6 This is a graph of field curvature and distortion at 8mm focal length for the optical system of an embodiment of the utility model;

[0020] Figure 7 This is a graph of field curvature and distortion at a focal length of 12mm for the optical system of an embodiment of the present utility model; DETAILED DESCRIPTION

[0021] It should be noted that the following detailed descriptions are exemplary and are intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which the present application belongs.

[0022] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or combinations thereof.

[0023] like Figures 1 to 7 As shown, a compact zoom optical system includes a compensation group, an aperture, a magnification group and an imaging group arranged in sequence along an incident light path; the lenses having optical power in the compensation group along the incident light path are, in sequence, a meniscus positive lens G1, a meniscus negative lens G2, a meniscus negative lens G3 and a meniscus positive lens G4; the lenses having optical power in the magnification group along the incident light path are, in sequence, a biconvex positive lens G5, a biconvex positive lens G6, a meniscus negative lens G7, a biconvex positive lens G8, a biconcave negative lens G9, a biconvex positive lens G10 and a meniscus negative lens G11, wherein the biconvex lens G6 and the meniscus lens G7 are cemented into a first cemented group H1, the biconvex lens G8 and the biconcave lens G9 are cemented into a second cemented group H2, and the biconvex lens G10 and the meniscus lens G11 are cemented into a third cemented group H3. The optical power of the first bonding group H1 is positive, the optical power of the second bonding group H2 is negative, and the optical power of the third bonding group H3 is positive; the total optical power of the compensation group is negative, and the total optical power of the zoom group is positive.

[0024] The object side of the meniscus positive lens G1 is convex, and the image side is concave; the object side of the meniscus negative lens G2 is convex, and the image side is concave; the object side of the meniscus negative lens G3 is convex, and the image side is concave; the object side of the meniscus positive lens G4 is convex, and the image side is concave; the object side of the biconvex positive lens G5 is convex, and the image side is convex; the object side of the biconvex positive lens G6 is convex, and the image side is convex; the object side of the meniscus negative lens G7 is concave, and the image side is convex; the object side of the biconvex positive lens G8 is convex, and the image side is convex; the object side of the biconvex negative lens G9 is concave, and the image side is concave; the object side of the biconvex positive lens G10 is convex, and the image side is convex; the object side of the meniscus negative lens G11 is concave, and the image side is convex.

[0025] The optical system adjusts the focal length by changing the relative positions of the compensation group and the zoom group. When the optical system zooms from the short focal length to the long focal length, the zoom group moves axially from the image plane to the object plane to adjust the magnification. When the optical system focuses from the close focal length to the telephoto focal length, the compensation group moves axially from the object plane to the image plane to compensate.

[0026] The optical system has eleven spherical mirror lenses. During the design process, the refractive indices and Abbe numbers of various glass materials are fully considered to optimize the aberrations borne by each optical component. It has a compact structure and a reasonable layout. Through careful parameter optimization, the optical focal length of each lens is reasonably distributed, effectively balancing the overall aberration of the optical system, thereby improving the imaging quality and meeting the image quality requirements of the optical system.

[0027] The zoom optical system has a compact optical structure, multiple focal lengths, and a flexible range of applications. Compared to fixed-focal-length lenses, zoom optical systems are more flexible in use. They can change the focal length within a certain range to perform real-time fine-tuning of the image according to different industrial application scenarios, meeting various special needs and improving the flexibility and application range of the equipment. Secondly, the compact zoom optical system also has high-resolution imaging and low distortion, ensuring clear images at different focal lengths within a certain range, thereby improving the accuracy of monitoring and detection.

[0028] In this embodiment, the air gap between the meniscus positive lens G1 and the meniscus negative lens G2 in the compensation group is 0.1 mm, the air gap between the meniscus negative lens G2 and the meniscus negative lens G3 is 3.71 mm, and the air gap between the meniscus negative lens G3 and the meniscus positive lens G4 is 4.03 mm.

[0029] In this embodiment, the air gap between the biconvex positive lens G5 and the first cemented group H1 in the zoom group is 0.1 mm, the air gap between the first cemented group H1 and the second cemented group H2 is 0.1 mm, and the air gap between the second cemented group H2 and the third cemented group H3 is 0.8 mm.

[0030] In this embodiment, the air gap between the compensation group and the aperture varies between 2.8-13.7 mm; the air gap between the aperture and the zoom group varies between 0.8-7.2 mm; and the air gap between the zoom group and the imaging group varies between 14.36-8.0 mm.

[0031] In this embodiment, the refractive index of the meniscus positive lens G1 is n1 and the Abbe number is V1, which satisfy the relationship: 1.72<n1<1.85, 48<V1<60; the refractive index of the meniscus negative lens G2 is n2 and the Abbe number is V2, which satisfy the relationship: 1.85<n2<1.95, 33<V2<36; the refractive index of the meniscus negative lens G3 is n3 and the Abbe number is V3, which satisfy the relationship: 1.78<n3<1.89, 39<V3<44; the refractive index of the meniscus positive lens G4 is n4 and the Abbe number is V4, which satisfy the relationship: 2.05<n4<1.15, 17<V4<18; the refractive index of the biconvex positive lens G5 is n5 and the Abbe number is V5, which satisfy the relationship Formula: 1.82<n5<1.85, 40<V5<45; the refractive index of the biconvex positive lens G6 is n6 and the Abbe number is V6, which satisfy the relationship: 1.49<n6<1.5, 74<V6<80; the refractive index of the meniscus negative lens G7 is n7 and the Abbe number is V7, which satisfy the relationship: 1.9<n7<1.92, 31<V7<34; the refractive index of the biconvex positive lens G8 is n8 and the Abbe number is V8, which satisfy the relationship: 1.92<n8<1.93, 20<V8<21; the refractive index of the biconcave negative lens G9 is n9 and the Abbe number is V9, which satisfy the relationship: 1.8<n9<1.81, 25<V9<26; the refractive index of the biconvex positive lens G10 is n 10 , Abbe number is V 10 , which satisfies the relationship: 1.58<n 10 <1.61、63<V 10 <69; the refractive index of the meniscus negative lens G11 is n 11 , Abbe number is V 11 , which satisfies the relationship: 1.83<n 11 <1.86、23<V 11 <25.

[0032] In order to achieve high resolution at multiple focal lengths, the design uses the change in the compensation group and the change in the magnification group to compensate for each other and offset each other to achieve clear imaging. In the first bonding group H1, crown glass G6 with excellent achromatic performance, low expansion coefficient, and low refractive index and heavy flint glass G7 with high temperature resistance, good chemical stability, and high refractive index are selected. G6 and G7 are bonded together to form a cemented lens, which neutralizes the refraction of light of different wavelengths, reduces light dispersion, and effectively corrects the chromatic aberration of the optical system. In the second bonding group H2, two high-refractive-index positive and negative lenses of heavy flint glass are bonded together to form a cemented lens, which reduces the reflection and scattering of light in the air gap, reduces glare, increases image brightness, and significantly improves the clarity and accuracy of vision, thereby improving imaging quality. In the third cemented group H3, a cemented lens is formed by sequentially bonding heavy phosphorus crown glass G10 and heavy flint glass G11. The materials are tightly connected, ensuring that the third cemented group H3 has better mechanical strength and shock resistance, which can effectively reduce the problem of optical system failure caused by vibration. At the same time, it can effectively reduce the absorption and reflection of light by the optical elements themselves, effectively improve the light transmittance of the optical system, and ensure the clarity and brightness of the image.

[0033] In this embodiment, all lenses are glass spherical lenses.

[0034] In this embodiment, the imaging group includes a flat glass G12 and an imaging surface, and the air gap between the flat glass G12 and the imaging surface is 0.1 mm.

[0035] The optical system achieves the following technical indicators: image plane size ≤φ8.8mm, EFFL=5.5mm~12mm, image space F / #=2.8, total optical length ∑<60mm, and operating wavelength: FdC (visible).

[0036] To achieve the above design parameters, the specific parameters of the optical system of this embodiment are shown in Table 1:

[0037] Table 1 Data of each lens in the optical system (unit: mm)

[0038]

[0039] For the biconvex lens G5, the curvature radius of the R10 surface is designed to be equal to the curvature radius of the R11 surface; for the biconvex lens G6, the curvature radius of the R12 surface is designed to be equal to the curvature radius of the R13 surface; for the biconcave lens G9, the curvature radius of the R16 surface is designed to be equal to the curvature radius of the R17 surface; this can effectively save time in the research and development of molds, and at the same time help to reduce manufacturing processes and production costs.

[0040] The MTF curve of the optical system is as follows: Figure 2As shown in the figure, when the focal length is 5.5mm, the edge field MTF is ≥0.15@150Lp / mm, and the center field MTF is ≥0.4@150Lp / mm; Figure 3 The figure shows that when the focal length is 8mm, the edge field MTF in the figure is ≥0.2@150Lp / mm, and the center field MTF is ≥0.4@150Lp / mm; Figure 4 The figure shows a focal length of 12mm. The MTF of the edge field of view is ≥0.2@150Lp / mm, and the MTF of the center field of view is ≥0.4@150Lp / mm, ensuring clear images at different focal lengths.

[0041] The field curvature and distortion curves of the optical system are as follows: Figure 5 The figure shows that when the focal length is 5.5mm, the field curvature is ≤±0.08mm and the optical distortion is ≤-0.8%. Figure 6 The figure shows that when the focal length is 8mm, the field curvature is ≤±0.08mm and the optical distortion is ≤-0.4%. Figure 7 The figure shows a 12mm focal length with field curvature ≤±0.08mm and optical distortion ≤0.4%, ensuring low field curvature and distortion at all focal lengths.

[0042] Unless otherwise stated, any numerical range disclosed for any technical solution disclosed in the present invention is a preferred numerical range. Those skilled in the art should understand that a preferred numerical range is merely a numerical range that provides a more significant or representative technical effect among a wide range of practicable values. Due to the large number of numerical values, it is impossible to enumerate them exhaustively. Therefore, only some numerical values ​​are disclosed in the present invention to illustrate the technical solution of the present invention. Furthermore, the numerical values ​​listed above should not be construed as limiting the scope of protection of the present invention.

[0043] If the present invention discloses or involves components or structural parts that are fixedly connected to each other, then, unless otherwise stated, the fixed connection can be understood as: a detachable fixed connection (for example, connection using bolts or screws), and can also be understood as: a non-detachable fixed connection (for example, riveting, welding). Of course, the mutual fixed connection can also be replaced by an integrated structure (for example, manufactured by integral molding using a casting process) (except where it is obviously not possible to use an integrated molding process).

[0044] In addition, unless otherwise stated, the terms used in any technical solution disclosed in the above-mentioned utility model to express positional relationships or shapes include states or shapes that are approximate, similar or close thereto.

[0045] Any component provided by the present invention can be assembled from multiple separate components, or can be a separate component manufactured by an integral forming process.

[0046] The above description is merely a preferred embodiment of the present invention and does not constitute any limitation thereto. Any person skilled in the art may utilize the above disclosure to modify or remodel the present invention into equivalent embodiments. However, any simple modifications, equivalent variations, and modifications to the above embodiments that do not depart from the technical content of the present invention and are based on the technical essence of the present invention shall remain within the scope of protection of the present invention.

Claims

1. A compact zoom optical system, characterized in that: The invention comprises a compensation group, an aperture, a zoom group and an imaging group arranged in sequence along the incident light path; the lenses having optical focal power in the compensation group along the incident light path are a meniscus positive lens G1, a meniscus negative lens G2, a meniscus negative lens G3 and a meniscus positive lens G4 in sequence; the lenses having optical focal power in the zoom group along the incident light path are a biconvex positive lens G5, a biconvex positive lens G6, a meniscus negative lens G7, a biconvex positive lens G8, a biconcave negative lens G9, a biconvex positive lens G10 and a meniscus negative lens G11 in sequence, wherein the biconvex lens G6 and the meniscus lens G7 are bonded to form a first cemented group H1, the biconvex lens G8 and the biconcave lens G9 are bonded to form a second cemented group H2, and the biconvex lens G10 and the meniscus lens G11 are bonded to form a third cemented group H3.

2. The compact zoom optical system according to claim 1, wherein: In the compensation group, the air gap between the meniscus positive lens G1 and the meniscus negative lens G2 is 0.1 mm, the air gap between the meniscus negative lens G2 and the meniscus negative lens G3 is 3.71 mm, and the air gap between the meniscus negative lens G3 and the meniscus positive lens G4 is 4.03 mm.

3. The compact zoom optical system according to claim 1, wherein: In the zoom group, the air gap between the biconvex positive lens G5 and the first cemented group H1 is 0.1 mm, the air gap between the first cemented group H1 and the second cemented group H2 is 0.1 mm, and the air gap between the second cemented group H2 and the third cemented group H3 is 0.8 mm.

4. The compact zoom optical system according to claim 1, wherein: The air gap between the compensation group and the diaphragm varies between 2.8-13.7 mm; the air gap between the diaphragm and the zoom group varies between 0.8-7.2 mm; and the air gap between the zoom group and the imaging group varies between 14.36-8.0 mm.

5. The compact zoom optical system according to claim 1, wherein: The refractive index of the meniscus positive lens G1 is n1 and the Abbe number is V1, which satisfy the relationship: 1.72<n1<1.85, 48<V1<60; the refractive index of the meniscus negative lens G2 is n2 and the Abbe number is V2, which satisfy the relationship: 1.85<n2<1.95, 33<V2<36; the refractive index of the meniscus negative lens G3 is n3 and the Abbe number is V3, which satisfy the relationship: 1.78<n3<1.89, 39<V3<44; the refractive index of the meniscus positive lens G4 is n4 and the Abbe number is V4, which satisfy the relationship: 2.05<n4<1.15, 17<V4<18; the refractive index of the biconvex positive lens G5 is n5 and the Abbe number is V5, which satisfy the relationship:

1. 82<n5<1.85, 40<V5<45; the refractive index of the biconvex positive lens G6 is n6 and the Abbe number is V6, which satisfy the relationship: 1.49<n6<1.5, 74<V6<80; the refractive index of the meniscus negative lens G7 is n7 and the Abbe number is V7, which satisfy the relationship: 1.9<n7<1.92, 31<V7<34; the refractive index of the biconvex positive lens G8 is n8 and the Abbe number is V8, which satisfy the relationship: 1.92<n8<1.93, 20<V8<21; the refractive index of the biconcave negative lens G9 is n9 and the Abbe number is V9, which satisfy the relationship: 1.8<n9<1.81, 25<V9<26; the refractive index of the biconvex positive lens G10 is n 10 , Abbe number is V 10 , which satisfies the relationship: 1.58<n 10 <1.61、63<V 10 <69; the refractive index of the meniscus negative lens G11 is n 11 , Abbe number is V 11 , which satisfies the relationship: 1.83<n 11 <1.86、23<V 11 <25.

6. The compact zoom optical system according to claim 1, wherein: All lenses are glass spherical lenses.

7. The compact zoom optical system according to claim 1, wherein: The imaging group includes a flat glass G12 and an imaging surface, and the air gap between the flat glass G12 and the imaging surface is 0.1 mm.

Images