High-resolution compact short-focus optical system

Abstract

The utility model relates to a high-resolution compact short-focus optical system, which comprises a front group A, a rear group B and an imaging group C which are sequentially arranged from left to right along the optical axis direction, and is characterized in that the front group A comprises a first lens with negative focal power, a second lens with positive focal power and a third lens with positive focal power which are sequentially arranged from left to right; the rear group B comprises a fourth lens with negative focal power, a fifth lens with positive focal power and a sixth lens with positive focal power which are sequentially arranged from left to right; and the imaging group C comprises plane glass and an imaging surface which are sequentially arranged from left to right. According to the utility model, the design is reasonable, through the reasonable optical system layout, the groups are compact, the branches are symmetrical, the stability and reliability of the optical system are ensured, higher pixels and a more compact structure are realized, and the cost is lower.

Description

Technical Field

[0001] This utility model belongs to the field of optical lens technology, and in particular relates to a high-resolution compact short-focal-length optical system. Background Technology

[0002] In recent years, with the transformation and upgrading of the manufacturing industry, screw fastening machines have been widely used in industrial production, greatly improving production efficiency. Especially in industries such as electronics, automobiles, home appliances, and communications, the miniaturization, precision, and large-scale production of products have led to a continuous increase in demand for automatic screw fastening machines. Furthermore, with advancements in mechanical manufacturing technology and the development of artificial intelligence, screw fastening machines are gradually evolving towards intelligent operation, incorporating machine vision capture systems and acquiring more intelligent functions such as automatic feeding, automatic positioning, and defect detection. High-precision machine vision system positioning significantly improves the accuracy and speed of screw fastening, thereby increasing production efficiency and product quality while reducing labor costs and labor intensity.

[0003] In the future, with the gradual rise of domestic brands and the development of emerging industries such as new energy, medical devices, and aerospace, new market demands will be brought to the screw fastening machine industry. At the same time, this will also place higher demands on the fastening accuracy and quality of screw fastening machines. Therefore, designing a high-resolution, compact, short-focal-length optical system to meet the broader screw fastening machine market will become very meaningful. Utility Model Content

[0004] The purpose of this invention is to provide a high-resolution, compact, short-focal-length optical system for use with screw machines, in order to achieve higher pixel counts and a more compact structure.

[0005] To achieve the above objectives, the technical solution adopted by this utility model is: a high-resolution compact short-focal-length optical system, the optical system comprising a front group A, a rear group B, and an imaging group C arranged sequentially from left to right along the optical axis; the front group A comprising a first lens with negative optical power, a second lens with positive optical power, and a third lens with positive optical power arranged sequentially from left to right; the rear group B comprising a fourth lens with negative optical power, a fifth lens with positive optical power, and a sixth lens with positive optical power arranged sequentially from left to right; and the imaging group C comprising a planar glass and an imaging surface arranged sequentially from left to right.

[0006] Furthermore, the first lens is a biconcave lens, with both its left and right sides being concave; the second lens is a biconvex lens, with both its left and right sides being convex; the third lens is a meniscus lens, with both its left and right sides being convex; the fourth lens is a biconcave lens, with both its left and right sides being concave; the fifth lens is a meniscus lens, with both its left and right sides being concave; and the sixth lens is a biconvex lens, with both its left and right sides being convex.

[0007] Furthermore, the air distance between the first lens and the second lens is 8.22 mm; the air distance between the second lens and the third lens is 0.1 mm; the air distance between the fourth lens and the fifth lens is 0.28 mm; the air distance between the fifth lens and the sixth lens is 0.1 mm; and the air distance from the flat glass to the imaging surface is 0.2 mm.

[0008] Furthermore, the air distance between the front group A and the rear group B is 10.99 mm.

[0009] Furthermore, an aperture is provided between the front group A and the rear group B; the air distance between the front group A and the aperture is 8.91 mm; the air distance between the aperture and the rear group B is 2.08 mm.

[0010] Furthermore, the optical system focuses the entire group during movement. When the object distance is 250mm, the air distance between the rear group B and the imaging group C is 11.91mm; when the object distance is at infinity, the air distance between the rear group B and the imaging group C is 11.35mm.

[0011] Furthermore, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, and the sixth lens are all all-glass spherical lenses, and the left and right sides of the first lens, the second lens, the third lens, the fourth lens, the fifth lens, and the sixth lens are all coated with anti-reflection coatings.

[0012] Furthermore, the total focal length f of the optical system, the focal length of the first lens is f1, the focal length of the second lens is f2, the focal length of the third lens is f3, the focal length of the fourth lens is f4, the focal length of the fifth lens is f5, and the focal length of the sixth lens is f6, where:

[0013] The ratio of f1 to f satisfies the following relationship: 1.0 < |f1 / f| < 1.37;

[0014] The ratio of f2 to f satisfies the following relationship: 1.65 < |f2 / f| < 2.30;

[0015] The ratio of f3 to f satisfies the following relationship: 3.28 < |f3 / f| < 3.83;

[0016] The ratio of f4 to f satisfies the following relationship: 0.47 < |f4 / f| < 0.79;

[0017] The ratio of f5 to f satisfies the following relationship: 1.50 < |f5 / f| < 2.02;

[0018] The ratio of f6 to f satisfies the following relationship: 0.94 < |f6 / f| < 1.25.

[0019] Furthermore, the first lens has a refractive index of n1 and an Abbe number of V1, satisfying the following relationships: 1.80 < n1 < 2.05, 34.0 < V1 < 35.5; the second lens has a refractive index of n2 and an Abbe number of V2, satisfying the following relationships: 1.57 < n2 < 1.62, 66.5 < V2 < 71.0; and the third lens has a refractive index of n3 and an Abbe number of V3, satisfying the following relationships: 1.62 < n3 < 1.72, 34.5 < V3 < 36. 0.5; The fourth lens has a refractive index of n4 and an Abbe number of V4, satisfying the following relationships: 1.64 < n4 < 1.95, 18.0 < V4 < 19.5; The fifth lens has a refractive index of n5 and an Abbe number of V5, satisfying the following relationships: 1.62 < n5 < 1.72, 33.0 < V5 < 37.0; The sixth lens has a refractive index of n6 and an Abbe number of V6, satisfying the following relationships: 1.65 < n6 < 1.80, 38.0 < V6 < 40.5.

[0020] Furthermore, the total optical power of the front group A is positive, and the total optical power of the rear group B is positive.

[0021] Compared with the prior art, the present invention has the following advantages: The present invention is reasonably designed. Through a reasonable optical system layout, its groups are compact and the distribution is symmetrical, which ensures the stability and reliability of the optical system, achieves higher pixel count, more compact structure, and more economical cost. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the optical system at an infinity object distance according to an embodiment of the present invention;

[0023] Figure 2 This is a schematic diagram of the optical system of this utility model at an object distance of 250mm;

[0024] Figure 3 It is an MTF curve at a 250mm object distance;

[0025] Figure 4 It is the MTF curve at a 500mm object distance;

[0026] Figure 5 It is the MTF curve at a 2000mm object distance;

[0027] Figure 6 It is the MTF curve of an object at infinity.

[0028] Figure 7 It shows the field curvature and distortion at a 250mm object distance;

[0029] Figure 8 It shows the field curvature and distortion at a 500mm object distance;

[0030] Figure 9 It shows the field curvature and distortion at an object distance of 2000mm;

[0031] Figure 10 It is the field curvature and distortion diagram of an object at infinity.

[0032] In the picture:

[0033] A - Front group A; B - Rear group B; C - Imaging group C; 1 - First lens; 2 - Second lens; 3 - Third lens; 4 - Fourth lens; 5 - Fifth lens; 6 - Sixth lens; 7 - Plane glass; 8 - Imaging plane; ST - Aperture stop. Detailed Implementation

[0034] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0035] In the description of this utility model, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0036] like Figure 1 As shown, this utility model aims to address the rise of the screw machine market and the development of emerging industries by providing a high-resolution, compact, short-focal-length optical system for use with it, achieving higher pixel counts, a more compact structure, and a more economical cost solution. Specifically, the optical system includes a front group A, a rear group B, and an imaging group C arranged sequentially from left to right along the optical axis from the object side to the image side. An aperture stop ST is provided between the front group A and the rear group B. The total optical power of the front group A is positive, and the total optical power of the rear group B is positive. The front group A includes a first lens with negative optical power, a second lens with positive optical power, and a third lens with positive optical power arranged sequentially from left to right. The rear group B includes a fourth lens with negative optical power, a fifth lens with positive optical power, and a sixth lens with positive optical power arranged sequentially from left to right. The imaging group C includes a planar glass and an imaging surface arranged sequentially from left to right.

[0037] In this embodiment, the first lens is a biconcave lens, with both its left and right sides being concave; the second lens is a biconvex lens, with both its left and right sides being convex; the third lens is a meniscus lens, with its left side being convex and its right side being concave; the fourth lens is a biconcave lens, with both its left and right sides being concave; the fifth lens is a meniscus lens, with its left side being concave and its right side being convex; and the sixth lens is a biconvex lens, with both its left and right sides being convex. The convex surfaces of the third and fourth lenses are both away from the aperture stop ST. It should be noted that here, the left side of the lens refers to the object side, and the right side refers to the image side.

[0038] In this embodiment, in the front group A, the air distance between the first lens and the second lens is 8.22 mm; the air distance between the second lens and the third lens is 0.1 mm.

[0039] In this embodiment, in the rear group B, the air distance between the fourth lens and the fifth lens is 0.28 mm; the air distance between the fifth lens and the sixth lens is 0.1 mm.

[0040] In this embodiment, in imaging group C, the air distance from the flat glass to the imaging surface is 0.2 mm.

[0041] In this embodiment, the air distance between the front group A and the rear group B is 10.99 mm. Specifically, the air distance between the front group A and the aperture is 8.91 mm, and the air distance between the aperture and the rear group B is 2.08 mm.

[0042] In this embodiment, the optical system uses a whole-group moving focusing method for focusing, that is, the front group A, the aperture and the rear group B move together as a whole. Specifically, when the object distance is 250mm, the air distance between the rear group B and the imaging group C is 11.91mm; when the object distance is at infinity, the air distance between the rear group B and the imaging group C is 11.35mm.

[0043] In this embodiment, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, and the sixth lens are all all-glass spherical lenses. The left and right sides of the first lens, the second lens, the third lens, the fourth lens, the fifth lens, and the sixth lens are all coated with anti-reflection films, which reduces the reflection of incident light on the surface of the element, increases the light transmittance, improves the brightness of the optical system, and ensures its imaging quality.

[0044] In this embodiment, the second lens is designed as a biconvex lens, and the material used is heavy phosphorus crown glass with low refractive index and low dispersion, which reduces the dispersion of light of different wavelengths on the spherical surface of the lens. In addition, the lens made of this material also has good temperature resistance and high strength, effectively improving the imaging quality of the optical system in high and low temperature environments.

[0045] In this embodiment, the total focal length f of the optical system, the focal length of the first lens is f1, the focal length of the second lens is f2, the focal length of the third lens is f3, the focal length of the fourth lens is f4, the focal length of the fifth lens is f5, and the focal length of the sixth lens is f6, wherein:

[0046] The ratio of f1 to f satisfies the following relationship: 1.0 < |f1 / f| < 1.37;

[0047] The ratio of f2 to f satisfies the following relationship: 1.65 < |f2 / f| < 2.30;

[0048] The ratio of f3 to f satisfies the following relationship: 3.28 < |f3 / f| < 3.83;

[0049] The ratio of f4 to f satisfies the following relationship: 0.47 < |f4 / f| < 0.79;

[0050] The ratio of f5 to f satisfies the following relationship: 1.50 < |f5 / f| < 2.02;

[0051] The ratio of f6 to f satisfies the following relationship: 0.94 < |f6 / f| < 1.25.

[0052] In this embodiment, the refractive index of the first lens is n1 and the Abbe number is V1, which satisfy the following relationships: 1.80 < n1 < 2.05 and 34.0 < V1 < 35.5.

[0053] In this embodiment, the refractive index of the second lens is n2 and the Abbe number is V2, which satisfy the following relationships: 1.57 < n2 < 1.62 and 66.5 < V2 < 71.0.

[0054] In this embodiment, the refractive index of the third lens is n3 and the Abbe number is V3, which satisfy the following relationships: 1.62 < n3 < 1.72 and 34.5 < V3 < 36.5.

[0055] In this embodiment, the refractive index of the fourth lens is n4 and the Abbe number is V4, which satisfy the following relationships: 1.64 < n4 < 1.95 and 18.0 < V4 < 19.5.

[0056] In this embodiment, the refractive index of the fifth lens is n5 and the Abbe number is V5, which satisfy the following relationships: 1.62 < n5 < 1.72 and 33.0 < V5 < 37.0.

[0057] In this embodiment, the refractive index of the sixth lens is n6 and the Abbe number is V6, which satisfy the following relationships: 1.65 < n6 < 1.80 and 38.0 < V6 < 40.5.

[0058] In this embodiment, the optical system consists of six all-glass spherical lenses, which are focused using a group-by-group moving focusing method. The design process fully considers the interrelationships between the lenses, the surface type, performance parameters, and cost factors. Through a reasonable optical system layout, the group is compact and the distribution is symmetrical, ensuring the stability and reliability of the optical system.

[0059] In this embodiment, the parameters of each lens are shown in the table below:

[0060] .

[0061] In this embodiment, the MTF curve of the optical system is as follows: Figure 3 The figure shows MTF ≥ 0.2 @ 200 lp / mm and MTF ≥ 0.4 @ 125 lp / mm at an object distance of 250 mm. Figure 4 The figure shows MTF ≥ 0.2@200lp / mm and MTF ≥ 0.4@125lp / mm at an object distance of 500mm. Figure 5 The figure shows MTF ≥ 0.2@200lp / mm and MTF ≥ 0.4@125lp / mm at an object distance of 2000mm. Figure 6 The figure shows the MTF at infinity object distance, with values ​​of MTF ≥ 0.2 @ 200 lp / mm and MTF ≥ 0.4 @ 125 lp / mm.

[0062] In this embodiment, the field curvature and distortion diagram of the optical system are as follows: Figure 7 As shown, at an object distance of 250 mm, the field curvature in the figure is ≤ ±0.05 mm, and the optical distortion is ≤ -0.1%; Figure 8 As shown, at an object distance of 500mm, the field curvature in the figure is ≤±0.05mm, and the optical distortion is ≤-0.1%; Figure 9 As shown, at an object distance of 2000mm, the field curvature in the figure is ≤±0.05mm, and the optical distortion is ≤-0.1%; Figure 10 As shown, at an object distance of infinity, the field curvature in the figure is ≤ ±0.05 mm, and the optical distortion is ≤ -0.1%.

[0063] In this embodiment, the optical system achieves the following technical specifications: f=12mm, relative aperture: F / #=2.8, target surface size ≤φ9.4mm, and working wavelength: FdC (visible).

[0064] If this utility model discloses or relates to mutually fixedly connected parts or structural components, then, unless otherwise stated, a fixed connection can be understood as: a detachable fixed connection (e.g., using bolts or screws), or a non-detachable fixed connection (e.g., riveting, welding). Of course, mutually fixed connections can also be replaced by an integral structure (e.g., manufactured using a casting process) (except where it is obviously impossible to use an integral forming process).

[0065] In addition, unless otherwise stated, the terms used to indicate positional relationships or shapes in any of the technical solutions disclosed in this utility model above include states or shapes that are similar to, close to, or approximate with them.

[0066] Any component provided by this utility model can be assembled from multiple individual components, or it can be a single component manufactured by a one-piece molding process.

[0067] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of this utility model and not to limit it; although the utility model has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications can still be made to the specific implementation of this utility model or equivalent substitutions can be made to some technical features without departing from the spirit of the technical solution of this utility model, and all such modifications and substitutions should be covered within the scope of the technical solution claimed by this utility model.

Claims

1. A high-resolution, compact, short-focal-length optical system, characterized in that: The optical system includes a front group A, a rear group B, and an imaging group C arranged sequentially from left to right along the optical axis. The front group A includes a first lens with negative optical power, a second lens with positive optical power, and a third lens with positive optical power arranged sequentially from left to right. The rear group B includes a fourth lens with negative optical power, a fifth lens with positive optical power, and a sixth lens with positive optical power arranged sequentially from left to right. The imaging group C includes a planar glass and an imaging surface arranged sequentially from left to right.

2. The high-resolution compact short-focal-length optical system according to claim 1, characterized in that: The first lens is a biconcave lens, with both its left and right sides being concave; the second lens is a biconvex lens, with both its left and right sides being convex; the third lens is a meniscus lens, with both its left and right sides being convex; the fourth lens is a biconcave lens, with both its left and right sides being concave; the fifth lens is a meniscus lens, with both its left and right sides being concave; and the sixth lens is a biconvex lens, with both its left and right sides being convex.

3. A high-resolution compact short-focal-length optical system according to claim 1 or 2, characterized in that: The air distance between the first and second lenses is 8.22 mm; the air distance between the second and third lenses is 0.1 mm; the air distance between the fourth and fifth lenses is 0.28 mm; the air distance between the fifth and sixth lenses is 0.1 mm; and the air distance from the flat glass to the imaging surface is 0.2 mm.

4. The high-resolution compact short-focal-length optical system according to claim 1, characterized in that: The air distance between the front group A and the rear group B is 10.99 mm.

5. A high-resolution compact short-focal-length optical system according to claim 1 or 4, characterized in that: An aperture is provided between the front group A and the rear group B; the air distance between the front group A and the aperture is 8.91 mm; the air distance between the aperture and the rear group B is 2.08 mm.

6. The high-resolution compact short-focal-length optical system according to claim 1, characterized in that: The optical system focuses for the movement of the entire group. When the object distance is 250mm, the air distance between the rear group B and the imaging group C is 11.91mm; when the object distance is at infinity, the air distance between the rear group B and the imaging group C is 11.35mm.

7. A high-resolution compact short-focal-length optical system according to claim 1, characterized in that: The first lens, the second lens, the third lens, the fourth lens, the fifth lens, and the sixth lens are all all-glass spherical lenses, and the left and right sides of the first lens, the second lens, the third lens, the fourth lens, the fifth lens, and the sixth lens are coated with anti-reflection coatings.

8. A high-resolution compact short-focal-length optical system according to claim 1, characterized in that: The optical system has a total focal length f, a focal length of f1 for the first lens, a focal length of f2 for the second lens, a focal length of f3 for the third lens, a focal length of f4 for the fourth lens, a focal length of f5 for the fifth lens, and a focal length of f6 for the sixth lens, where: The ratio of f1 to f satisfies the following relationship: 1.0 < |f1 / f| < 1.37; The ratio of f2 to f satisfies the following relationship: 1.65 < |f2 / f| < 2.30; The ratio of f3 to f satisfies the following relationship: 3.28 < |f3 / f| < 3.83; The ratio of f4 to f satisfies the following relationship: 0.47 < |f4 / f| < 0.79; The ratio of f5 to f satisfies the following relationship: 1.50 < |f5 / f| < 2.02; The ratio of f6 to f satisfies the following relationship: 0.94 < |f6 / f| < 1.

25.

9. A high-resolution compact short-focal-length optical system according to claim 1, characterized in that: The first lens has a refractive index of n1 and an Abbe number of V1, satisfying the following relationships: 1.80 < n1 < 2.05, 34.0 < V1 < 35.5; the second lens has a refractive index of n2 and an Abbe number of V2, satisfying the following relationships: 1.57 < n2 < 1.62, 66.5 < V2 < 71.0; the third lens has a refractive index of n3 and an Abbe number of V3, satisfying the following relationships: 1.62 < n3 < 1.72, 34.5 < V3 < 36.

5. The fourth lens has a refractive index of n4 and an Abbe number of V4, satisfying the following relationships: 1.64 < n4 < 1.95, 18.0 < V4 < 19.5; the fifth lens has a refractive index of n5 and an Abbe number of V5, satisfying the following relationships: 1.62 < n5 < 1.72, 33.0 < V5 < 37.0; the sixth lens has a refractive index of n6 and an Abbe number of V6, satisfying the following relationships: 1.65 < n6 < 1.80, 38.0 < V6 < 40.

5.

10. A high-resolution compact short-focal-length optical system according to claim 1, characterized in that: The total optical power of the front group A is positive, and the total optical power of the back group B is positive.

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