Diaphragm preposed athermalization robot vision optical system
By designing a front-mounted thermal-free robot vision optical system in a robot vision lens, the combination of glass and plastic lenses and spherical and aspherical lens structures are adopted, the imaging instability caused by temperature drift is solved, and a high resolution, wide field angle and low-cost robot vision lens is achieved.
Patent Information
- Application Number
- CN202420595800.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-03-26
- Publication Date
- 2025-04-15
- Estimated Expiration
- 2034-03-26
AI Technical Summary
Existing robot vision lenses have temperature drift problems in high and low temperature environments, resulting in unstable imaging, low resolution, small field angle, large architecture volume, and high cost.
A thermal-free robot vision optical system is designed for front-mounted diaphragm. By fronting the diaphragm on the side of the glass first lens, and using a combination of glass and plastic lenses, including a positive biconvex lens, a negative lens and an aspherical lens, combined with a spherical and aspherical lens structure design, aberration correction and temperature stability of lens imaging within the temperature range of 0℃ to +40℃ are achieved.
Maintain clear imaging within the temperature range of 0℃~+40℃, ensure stable image quality, and achieve high resolution (13 million pixels) and wide field of view angle robot vision optical system, reducing the total length and cost of the lens.
Smart Images
Figure CN222762327U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the field of robot vision optical systems, and in particular relates to a robot vision optical system with an athermal diaphragm in front. Background Art
[0002] In industry, robot vision lenses can be used in automated production lines to help robots detect and identify products, thereby improving production efficiency and quality. It can help robots perform precise positioning, measurement and detection, avoid human errors, and improve the degree of automation of production lines.
[0003] In the home, robot vision lenses can be used in smart home systems, such as smart security monitoring systems, smart home assistants, etc. Through robot vision lenses, home remote monitoring, intelligent identification and automatic control can be achieved, improving home security and convenience of life.
[0004] As robot vision lenses are increasingly used in detection applications, the requirements for their performance are also getting higher and higher. However, the robot lenses on the market have low resolution, small field of view, and large structure size. And when the robot vision lens adopts an all-glass lens design, the lens cost price will be relatively high. The use of plastic lenses can improve the price competitiveness of the lens, but the side effect of using plastic aspheric lenses is the focus drift problem caused by the large thermal expansion coefficient. Since the refractive index of the lens material will change due to temperature, the lens size, lens barrel material, and lens mount material will expand and contract with temperature changes. These factors cause ordinary robot lenses to have different imaging back focus (back intercept) in high and low temperature environments, which is called temperature drift of lens imaging. Utility Model Content
[0005] The utility model aims to provide an athermal robot vision optical system with a pre-aperture aperture, which can correct aberrations within a temperature range of 0°C to +40°C, so that the lens can maintain clear imaging within a temperature range of 0°C to +40°C and ensure stable image quality.
[0006] In order to achieve the above purpose, the technical solution adopted by the utility model is:
[0007] A athermal robot vision optical system with an aperture in front, the athermal robot vision optical system comprising, from the object side to the image side, an aperture, a first lens G1 made of glass, a second lens P2 made of plastic, a third lens P3 made of plastic, a fourth lens P4 made of plastic, a fifth lens P5 made of plastic, and a glass filter E6;
[0008] The first lens G1 is a positive biconvex lens; the second lens P2 is a negative lens, and the object side surface is convex and aspherical, and the image side surface is concave and aspherical; the third lens P3 is a positive lens, and the object side surface is convex and aspherical, and the image side surface is convex and aspherical; the fourth lens P4 is a negative lens, and the object side surface is concave and aspherical, and the image side surface is convex and aspherical; the fifth lens P5 is a positive lens, and the object side surface is convex and aspherical, and the image side surface is concave and aspherical.
[0009] Several optional methods are also provided below, but they are not intended to be additional limitations on the above-mentioned overall solution, but are merely further supplements or preferences. Under the premise that there are no technical or logical contradictions, each optional method can be combined with the above-mentioned overall solution separately, and multiple optional methods can also be combined.
[0010] Preferably, the refractive indices of the first lens G1, the second lens P2, the third lens P3, the fourth lens P4, the fifth lens P5 and the glass filter E6 satisfy the following relationship:
[0011] 1.70≤nd1≤2.00, 1.50≤nd2≤1.80, 1.30≤nd3≤1.70, 1.50≤nd4≤1.80, 1.30≤nd5≤1.70, 1.45≤nd6≤1.60, wherein nd1, nd2, nd3, nd4, nd5 and nd6 are refractive indices of the first lens G1, the second lens P2, the third lens P3, the fourth lens P4, the fifth lens P5 and the glass filter E6 respectively.
[0012] Preferably, the Abbe numbers of the first lens G1, the second lens P2, the third lens P3, the fourth lens P4, the fifth lens P5 and the glass filter E6 satisfy the following relationship:
[0013] 35≤vd1≤45, 23≤vd2≤35, 45≤vd3≤65, 23≤vd4≤35, 45≤vd5≤65, 60≤vd6≤68, where vd1, vd2, vd3, vd4, vd5 and vd6 are the Abbe numbers of the first lens G1, the second lens P2, the third lens P3, the fourth lens P4, the fifth lens P5 and the glass filter E6 respectively.
[0014] Preferably, the curvature radii of the first lens G1, the second lens P2, the third lens P3, the fourth lens P4 and the fifth lens P5 satisfy the following relationship:
[0015] 10 ≤ r1 ≤ 15, -15 ≤ r2 ≤ -10, 2 ≤ r3 ≤ 5, 0.5 ≤ r4 ≤ 3, 6 ≤ r5 ≤ 9, -3 ≤ r6 ≤ -1, -3 ≤ r7 ≤ -0.5, -3 ≤ r8 ≤ -1, 0.5 ≤ r9 ≤ 2, 0.6 ≤ r10 ≤ 2, where r1, r3, r5, r7, and r9 are the curvature radii of the object sides of the first lens G1, the second lens P2, the third lens P3, the fourth lens P4, and the fifth lens P5 respectively, and r2, r4, r6, r8, and r10 are the curvature radii of the image sides of the first lens G1, the second lens P2, the third lens P3, the fourth lens P4, and the fifth lens P5 respectively.
[0016] Preferably, the focal lengths of the first lens G1, the second lens P2, the third lens P3, the fourth lens P4, and the fifth lens P5 satisfy the following relationship:
[0017] 0.68 < f1 / f < 1.82, -2.06 < f2 / f < -1.38, 0.25 < f3 / f < 1.37, -1.48 < f4 / f < -0.12, 3.98 < f5 / f < 5.32, where f1 is the effective focal length of the first lens G1, f2 is the effective focal length of the second lens P2, f3 is the effective focal length of the third lens P3, f4 is the effective focal length of the fourth lens P4, f5 is the effective focal length of the fifth lens P5, and f is the effective focal length of the anastigmatic robot vision optical system with the diaphragm in front.
[0018] Preferably, the aspheric formulas of the second lens P2, the third lens P3, the fourth lens P4, and the fifth lens P5 are:
[0019]
[0020] In the formula, z is the axial distance from the vertex of the surface to the vertex at the position along the optical axis where the height perpendicular to the optical axis is h, c represents the curvature at the vertex of the aspheric surface, K is the conic coefficient, and A4, A6, A8, A 10 are the coefficients of the even-order aspheric high-order terms.
[0021] Preferably, the thicknesses of the first lens G1, the second lens P2, the third lens P3, the fourth lens P4, the fifth lens P5, and the glass filter E6 satisfy the following relationship:
[0022] 0.7≤d1≤1.1, 0.4≤d3≤0.6, 1.5≤d5≤1.8, 0.3≤d7≤0.6, 0.7≤d9≤0.9, 0.6≤d11≤0.8, wherein d1 is the thickness of the first lens G1, d3 is the thickness of the second lens P2, d5 is the thickness of the third lens P3, d7 is the thickness of the fourth lens P4, d9 is the thickness of the fifth lens P5, and d11 is the thickness of the glass filter E6, and the unit of thickness is millimeter.
[0023] Preferably, the distances between the first lens G1, the second lens P2, the third lens P3, the fourth lens P4, the fifth lens P5, the glass filter E6 and the image plane satisfy the following relationship:
[0024] 0.2≤d2≤0.4, 0.2≤d4≤0.4, 0.2≤d6≤0.4, 0.1≤d8≤0.3, 0.6≤d10≤0.9, 0.7≤d12≤0.9, wherein d2 is the distance between the first lens G1 and the second lens P2, d4 is the distance between the second lens P2 and the third lens P3, d6 is the distance between the third lens P3 and the fourth lens P4, d8 is the distance between the fourth lens P4 and the fifth lens P5, d10 is the distance between the fifth lens P5 and the glass filter E6, and d12 is the distance between the glass filter E6 and the image plane, and the unit of the distance is millimeter.
[0025] The utility model provides an athermal robot vision optical system with a pre-aperture aperture. The apex is placed on the object side of the first lens (glass) through a first lens (glass), a second lens to a fifth lens (plastic) and a material combination. The apex can be corrected for spherical aberration, astigmatism, coma, chromatic aberration and the like within a temperature range of 0°C to +40°C, and can compensate for changes in air spacing caused by temperature changes in the lens barrel material and the lens mount material in the lens, thereby achieving a rear focus zero displacement, allowing the lens to maintain clear imaging within a temperature range of 0°C to +40°C, and ensuring stable image quality.
[0026] The utility model adopts a lens structure design combining a spherical surface (Sphere Surface) and an aspherical surface (Asphere Surface), and the first lens and the second lens, the fourth lens and the fifth lens are a combination of a positive lens and a negative lens, which can well correct aberrations, so that other parameters, such as distortion, analysis, chromatic aberration, image circle, main ray angle, etc. meet the design requirements of the robot lens, realize wide-band imaging of 455nm~655nm, and enable the lens resolution to reach 13 million pixels. BRIEF DESCRIPTION OF THE DRAWINGS
[0027] Figure 1This is a schematic diagram of the structure of a robot vision optical system with athermal aperture in front of the utility model;
[0028] Figure 2 This is the MTF curve diagram of the utility model when the resolution is 223lp / mm;
[0029] Figure 3 This is the defocus curve diagram of the utility model at 20°C;
[0030] Figure 4 This is the defocus curve diagram of the utility model at 0°C;
[0031] Figure 5 This is the defocus curve diagram of the utility model at 40°C;
[0032] Figure 6 It is the field curvature and distortion diagram of the utility model;
[0033] Figure 7 This is an illumination curve diagram of the present utility model. DETAILED DESCRIPTION
[0034] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.
[0035] It should be noted that when a component is referred to as being “connected” to another component, it may be directly connected to the other component or there may be a central component; when a component is referred to as being “fixed” to another component, it may be directly fixed to the other component or there may be a central component.
[0036] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention.
[0037] In order to overcome the problems of low resolution, small field of view, large structure volume and temperature drift of the robot lens in the prior art, the present embodiment provides an athermal robot vision optical system with a pre-aperture aperture.
[0038] like Figure 1As shown, the utility model is a pre-aperture athermal robot vision optical system, which includes, from the object side to the image side, an aperture, a first lens G1 made of glass, a second lens P2 made of plastic, a third lens P3 made of plastic, a fourth lens P4 made of plastic, a fifth lens P5 made of plastic, and a glass filter E6.
[0039] The first lens G1 is a positive biconvex lens; the second lens P2 is a negative lens, and the object side surface is convex and aspherical, and the image side surface is concave and aspherical; the third lens P3 is a positive lens, and the object side surface is convex and aspherical, and the image side surface is convex and aspherical; the fourth lens P4 is a negative lens, and the object side surface is concave and aspherical, and the image side surface is convex and aspherical; the fifth lens P5 is a positive lens, and the object side surface is convex and aspherical, and the image side surface is concave and aspherical. The aspherical formula is:
[0040]
[0041] Where z is the axial distance from the surface to the vertex at a height h perpendicular to the optical axis along the optical axis, c represents the curvature at the vertex of the aspheric surface, K is the cone coefficient, A4, A6, A8, A 10 is the coefficient of the higher-order term of the even-order aspheric surface.
[0042] The utility model uses a first lens (glass), a second lens to a fifth lens (plastic) and a material combination, and places the aperture in front of the object side of the first lens (glass), which can correct aberrations within a temperature range of 0°C to +40°C, so that the lens maintains clear imaging within a temperature range of 0°C to +40°C, and ensures stable image quality. At the same time, by adopting a lens structure design combining a spherical surface (Sphere Surface) and an aspherical surface (Asphere Surface), and the first lens and the second lens, the fourth lens and the fifth lens are a combination of a positive lens and a negative lens, the aberration can be well corrected, and other parameters, such as distortion, resolution, chromatic aberration, image circle, main ray angle, etc., meet the design requirements of the robot lens, and achieve wide-band imaging of 455nm to 655nm, and the lens resolution can reach 13 million pixels.
[0043] On the basis of the above structure, the utility model controls the lens parameters so that the total length of the entire visual optical system is short and has a larger field of view angle.
[0044] The refractive indices of the optical system of the present utility model satisfy the following relationships: 1.70 ≤ nd1 ≤ 2.00, 1.50 ≤ nd2 ≤ 1.80, 1.30 ≤ nd3 ≤ 1.70, 1.50 ≤ nd4 ≤ 1.80, 1.30 ≤ nd5 ≤ 1.70, 1.45 ≤ nd6 ≤ 1.60, where nd1, nd2, nd3, nd4, and nd5 are the refractive indices of the first lens G1, the second lens P2, the third lens P3, the fourth lens P4, the fifth lens P5, and the glass filter E6, respectively.
[0045] The Abbe numbers of the optical system of the present utility model satisfy the following relationships: 35 ≤ vd1 ≤ 45, 23 ≤ vd2 ≤ 35, 45 ≤ vd3 ≤ 65, 23 ≤ vd4 ≤ 35, 45 ≤ vd5 ≤ 65, 60 ≤ vd6 ≤ 68, where vd1, vd2, vd3, vd4, vd5, and vd6 are the Abbe numbers of the first lens G1, the second lens P2, the third lens P3, the fourth lens P4, the fifth lens P5, and the glass filter E6, respectively.
[0046] The radius of curvature of the optical system of the present utility model satisfies the following relationships: 10 ≤ r1 ≤ 15, -15 ≤ r2 ≤ -10, 2 ≤ r3 ≤ 5, 0.5 ≤ r4 ≤ 3, 6 ≤ r5 ≤ 9, -3 ≤ r6 ≤ -1, -3 ≤ r7 ≤ -0.5, -3 ≤ r8 ≤ -1, 0.5 ≤ r9 ≤ 2, 0.6 ≤ r10 ≤ 2, where r1, r3, r5, r7, and r9 are the radius of curvature of the object side surfaces of the first lens G1, the second lens P2, the third lens P3, the fourth lens P4, and the fifth lens P5, respectively, and r2, r4, r6, r8, and r10 are the radius of curvature of the image side surfaces of the first lens G1, the second lens P2, the third lens P3, the fourth lens P4, and the fifth lens P5, respectively.
[0047] The focal lengths of the optical system of the present utility model satisfy the following relationships: 0.68 < f1 / f < 1.82, -2.06 < f2 / f < -1.38, 0.25 < f3 / f < 1.37, -1.48 < f4 / f < -0.12, 3.98 < f5 / f < 5.32, where f1 is the effective focal length of the first lens G1, f2 is the effective focal length of the second lens P2, f3 is the effective focal length of the third lens P3, f4 is the effective focal length of the fourth lens P4, f5 is the effective focal length of the fifth lens P5, and f is the effective focal length of the athermalized robot vision optical system with a front diaphragm.
[0048] The thickness of the optical system of the present invention satisfies the following relationship: 0.7≤d1≤1.1, 0.4≤d3≤0.6, 1.5≤d5≤1.8, 0.3≤d7≤0.6, 0.7≤d9≤0.9, 0.6≤d11≤0.8, wherein d1 is the thickness of the first lens G1, d3 is the thickness of the second lens P2, d5 is the thickness of the third lens P3, d7 is the thickness of the fourth lens P4, d9 is the thickness of the fifth lens P5, d11 is the thickness of the glass filter E6, and the unit of thickness is millimeter. Controlling the thickness of each lens is conducive to correcting aberrations and mutual compensation, thereby improving imaging quality.
[0049] The spacing of the optical system of the utility model satisfies the following relationship: 0.2≤d2≤0.4, 0.2≤d4≤0.4, 0.2≤d6≤0.4, 0.1≤d8≤0.3, 0.6≤d10≤0.9, 0.7≤d12≤0.9, wherein d2 is the spacing between the first lens G1 and the second lens P2, d4 is the spacing between the second lens P2 and the third lens P3, d6 is the spacing between the third lens P3 and the fourth lens P4, d8 is the spacing between the fourth lens P4 and the fifth lens P5, d10 is the spacing between the fifth lens P5 and the glass filter E6, d12 is the spacing between the glass filter E6 and the image plane, and the spacing unit is millimeter. Control of the spacing is conducive to reducing the total length of the lens while ensuring the imaging quality.
[0050] The utility model adjusts the optical power of each lens to compensate for each other and controls the thickness of each lens, which is beneficial to correcting aberrations and mutual compensation, can reduce tolerance sensitivity and reduce the difficulty in the molding process, and is beneficial to shortening the overall length of the lens. The overall optical length of the optical system of the utility model is less than 9.1mm, making the structure more compact, making the lens more ultra-thin and miniaturized, and on this basis ensuring a larger field of view angle, achieving short overall length and large field of view imaging.
[0051] In order to intuitively demonstrate the advantages of the athermal robot vision optical system with a pre-aperture aperture of the present invention, a specific example is used below for illustration, but the specific implementation of the present invention is not limited thereto.
[0052] In this implementation case, the five lenses and glass filters (filters and chip protection glass) of the athermal robot vision optical system in front of the aperture have a total of twelve surfaces, of which the surface shape, radius of curvature, lens thickness, lens spacing, lens refractive index, Abbe number and cone coefficient values meet the following conditions respectively:
[0053] The optical parameters of the athermal robot vision optical system with an aperture pre-aperture are shown in Table 1, the aspheric coefficients are shown in Table 2, and the relative focal lengths of the lenses are shown in Table 3.
[0054] Table 1 Optical parameters
[0055] Surf Type Radius Thickness Index ABB S101 Sphere 13.331 0.954 1.88 40.8 S102 Sphere -13.331 0.358 S201 Asphere 3.907 0.557 1.63 23.4 S202 Asphere 2.003 0.287 S301 Asphere 7.032 1.709 1.54 56.0 S302 Asphere -1.904 0.289 S401 Asphere -1.090 0.495 1.63 23.4 S402 Asphere -1.796 0.106 S501 Asphere 1.368 0.797 1.54 56.0 S502 Asphere 1.238 0.800 S601 Sphere INFINITY 0.700 1.52 64.2 S602 Sphere INFINITY 0.761 IMA Sphere INFINITY TOTALLENGTH: 7.813
[0056] Table 2 Aspheric coefficients
[0057] Surf K <![CDATA[A4]]> <![CDATA[A6]]> <![CDATA[A8]]> <![CDATA[A 10 ]]> S201 -22.793 -0.014 -0.012 3.099E-03 -1.012E-03 S202 -5.103 -0.011 -3.840E-03 -3.374E-04 9.125E-05 S301 7.223 -0.018 -3.140E-03 2.527E-03 -2.449E-04 S302 -0.379 0.010 5.780E-004 -3.474E-04 3.334E-04 S401 -4.625 2.026E-03 5.941E-03 3.987E-04 -2.344E-04 S402 -5.674 9.017E-03 2.113E-03 5.607E-04 -9.498E-05 S501 -4.082 -0.032 1.344E-03 3.632E-04 -2.428E-05 S502 -2.946 -0.029 3.395E-03 -2.516E-04 8.830E-06
[0058] Table 3 Relative focal lengths of lenses
[0059]
[0060]
[0061] Note: In the table, Surf indicates the surface of the lens or glass filter, Type indicates the surface type, Radius indicates the radius of curvature (in mm), Thickness indicates the thickness and spacing (in mm, and the row with a numerical value of the refractive index (e.g., 0.954) indicates the physical thickness of the lens itself, and the row with an infinite value of the refractive index (e.g., 0.358) indicates the spacing between the current object and the next object), Index indicates the refractive index, ABB indicates the Abbe number, and S101, S201, S301, S401, S501, and S601 are respectively The object side surfaces of the first lens G1, the second lens P2, the third lens P3, the fourth lens P4, the fifth lens P5 and the glass filter E6, S102, S202, S302, S402, S502 and S602 are respectively the image side surfaces of the first lens G1, the second lens P2, the third lens P3, the fourth lens P4, the fifth lens P5 and the glass filter E6, IMA is the image plane, TOTALLENGTH is the entire optical system, Sphere is the spherical surface, Asphere is the aspherical surface, and INFINITY is infinity.
[0062] Optical tests were performed based on the athermalized robot vision optical system in front of the aperture in this embodiment. The test results are as follows: Figures 2 to 7 shown.
[0063] Figure 2 This is the MTF curve of this embodiment when the resolution is 223lp / mm. It can be seen from the figure that the central field MTF is higher than 50% at the Nyquist frequency of 223lp / mm, and the field modulation transfer function within 0.7 is higher than 40%. There is a slight astigmatism, and the robot visual optical system has excellent image quality.
[0064] Figure 3 This is the defocus curve of this embodiment at 20°C. The defocus curve shows the relationship between the meridian and sagittal MTF and the defocus amount of different fields of view when the spatial frequency is set to 223lp / mm. The horizontal axis of the figure is the defocus amount, and the vertical axis is the contrast. Through this figure, it can be seen whether the best focal plane of each field of view is relatively consistent and whether the MTF is sensitive to defocus. Figure 3It can be seen that the best focal planes of each field of view are basically the same, and the image quality of each field of view is uniform and clear.
[0065] Figure 4 is the defocus curve of this embodiment at 0°C, Figure 4 It can be seen that at a low temperature of 0°C, compared with the defocus curve at 20°C, there is no obvious defocus and the image quality is clear.
[0066] Figure 5 is the defocus curve of this embodiment at 40°C. Figure 5 It can be seen that at a high temperature of 40°C, compared with the defocus curve at 20°C, there is no obvious defocus and the image quality is clear.
[0067] Figure 6 The field curvature and distortion diagram of this embodiment shows that the maximum field curvature of the entire field of view is less than 0.026 mm, and the maximum distortion is -0.898%, which meets the design requirements. The optical system has a strong aberration correction capability.
[0068] Figure 7 This is an illumination curve diagram of the utility model. As can be seen from the diagram, it reflects the illumination ratio of each field of view relative to the 0° field of view, and the relative illumination of the entire field of view is better than 50%.
[0069] From the experimental results, it can be seen that the total optical length of the robot vision optical system with an aperture in front and athermalization in this embodiment is 7.8 mm, the field of view angle is 70 degrees, and clear imaging is maintained within the temperature range of 0°C to +40°C, and the image quality is stable, thereby realizing a robot vision optical system with high pixel, wide band, large field of view, aperture in front, athermalization, and short total length.
[0070] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.
[0071] The above-mentioned embodiments only express several implementation methods of the utility model, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the utility model. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the utility model, which all belong to the protection scope of the utility model. Therefore, the protection scope of the utility model shall be based on the attached claims.
Claims
1. A robot vision optical system with athermal aperture, characterized in that: The athermal robot vision optical system with a stop in front comprises, from the object side to the image side, a stop, a first lens (G1) made of glass, a second lens (P2) made of plastic, a third lens (P3) made of plastic, a fourth lens (P4) made of plastic, a fifth lens (P5) made of plastic, and a glass filter (E6); The first lens (G1) is a positive biconvex lens; the second lens (P2) is a negative lens, and the object side surface is convex and aspherical, and the image side surface is concave and aspherical; the third lens (P3) is a positive lens, and the object side surface is convex and aspherical, and the image side surface is convex and aspherical; the fourth lens (P4) is a negative lens, and the object side surface is concave and aspherical, and the image side surface is convex and aspherical; the fifth lens (P5) is a positive lens, and the object side surface is convex and aspherical, and the image side surface is concave and aspherical.
2. The athermalized robot vision optical system in front of the aperture according to claim 1, characterized in that: The refractive indices of the first lens (G1), the second lens (P2), the third lens (P3), the fourth lens (P4), the fifth lens (P5) and the glass filter (E6) satisfy the following relationship: 1.70≤nd1≤2.00, 1.50≤nd2≤1.80, 1.30≤nd3≤1.70, 1.50≤nd4≤1.80, 1.30≤nd5≤1.70, 1.45≤nd6≤1.60, wherein nd1, nd2, nd3, nd4, nd5 and nd6 are the refractive indices of the first lens (G1), the second lens (P2), the third lens (P3), the fourth lens (P4), the fifth lens (P5) and the glass filter (E6), respectively.
3. The athermalized robot vision optical system in front of the aperture according to claim 1, characterized in that: The Abbe numbers of the first lens (G1), the second lens (P2), the third lens (P3), the fourth lens (P4), the fifth lens (P5) and the glass filter (E6) satisfy the following relationship: 35≤vd1≤45, 23≤vd2≤35, 45≤vd3≤65, 23≤vd4≤35, 45≤vd5≤65, 60≤vd6≤68, wherein vd1, vd2, vd3, vd4, vd5 and vd6 are the Abbe numbers of the first lens (G1), the second lens (P2), the third lens (P3), the fourth lens (P4), the fifth lens (P5) and the glass filter (E6), respectively.
4. The athermalized robot vision optical system in front of the aperture according to claim 1, characterized in that: The curvature radii of the first lens (G1), the second lens (P2), the third lens (P3), the fourth lens (P4) and the fifth lens (P5) satisfy the following relationship: 10 ≤ r1 ≤ 15, -15 ≤ r2 ≤ -10, 2 ≤ r3 ≤ 5, 0.5 ≤ r4 ≤ 3, 6 ≤ r5 ≤ 9, -3 ≤ r6 ≤ -1, -3 ≤ r7 ≤ -0.5, -3 ≤ r8 ≤ -1, 0.5 ≤ r9 ≤ 2, 0.6 ≤ r10 ≤ 2, where r1, r3, r5, r7, and r9 are the curvature radii of the object sides of the first lens (G1), the second lens (P2), the third lens (P3), the fourth lens (P4), and the fifth lens (P5) respectively, and r2, r4, r6, r8, and r10 are the curvature radii of the image sides of the first lens (G1), the second lens (P2), the third lens (P3), the fourth lens (P4), and the fifth lens (P5) respectively.
5. The athermalized robot vision optical system in front of the aperture according to claim 1, characterized in that: The focal lengths of the first lens (G1), the second lens (P2), the third lens (P3), the fourth lens (P4), and the fifth lens (P5) satisfy the following relationship: 0.68 < f1 / f < 1.82, -2.06 < f2 / f < -1.38, 0.25 < f3 / f < 1.37, -1.48 < f4 / f < -0.12, 3.98 < f5 / f < 5.32, where f1 is the effective focal length of the first lens (G1), f2 is the effective focal length of the second lens (P2), f3 is the effective focal length of the third lens (P3), f4 is the effective focal length of the fourth lens (P4), f5 is the effective focal length of the fifth lens (P5), and f is the effective focal length of the athermalized robot vision optical system with a front diaphragm.
6. The athermalized robot vision optical system in front of the aperture according to claim 1, characterized in that: The aspheric formulas of the second lens (P2), the third lens (P3), the fourth lens (P4), and the fifth lens (P5) are: Where z is the axial distance from the surface to the vertex at a height h perpendicular to the optical axis along the optical axis, c represents the curvature at the vertex of the aspheric surface, K is the cone coefficient, A4, A6, A8, A 10 is the coefficient of the higher-order term of the even-order aspheric surface.
7. The athermalized robot vision optical system in front of the aperture according to claim 1, characterized in that: The thicknesses of the first lens (G1), the second lens (P2), the third lens (P3), the fourth lens (P4), the fifth lens (P5), and the glass filter (E6) satisfy the following relationship: 0.7 ≤ d1 ≤ 1.1, 0.4 ≤ d3 ≤ 0.6, 1.5 ≤ d5 ≤ 1.8, 0.3 ≤ d7 ≤ 0.6, 0.7 ≤ d9 ≤ 0.9, 0.6 ≤ d11 ≤ 0.8, where d1 is the thickness of the first lens (G1), d3 is the thickness of the second lens (P2), d5 is the thickness of the third lens (P3), d7 is the thickness of the fourth lens (P4), d9 is the thickness of the fifth lens (P5), and d11 is the thickness of the glass filter (E6), and the thickness unit is millimeter.
8. The athermalized robot vision optical system in front of the aperture according to claim 1, characterized in that: The distances between the first lens (G1), the second lens (P2), the third lens (P3), the fourth lens (P4), the fifth lens (P5), the glass filter (E6), and the image plane satisfy the following relationship: 0.2≤d2≤0.4, 0.2≤d4≤0.4, 0.2≤d6≤0.4, 0.1≤d8≤0.3, 0.6≤d10≤0.9, 0.7≤d12≤0.9, wherein d2 is a distance between the first lens (G1) and the second lens (P2), d4 is a distance between the second lens (P2) and the third lens (P3), d6 is a distance between the third lens (P3) and the fourth lens (P4), d8 is a distance between the fourth lens (P4) and the fifth lens (P5), d10 is a distance between the fifth lens (P5) and the glass filter (E6), and d12 is a distance between the glass filter (E6) and the image plane, and the unit of the distance is millimeter.