Optical lens and automatic guide transport vehicle

Abstract

The utility model discloses an optical lens and an automated guided vehicle. The optical lens comprises a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens and a seventh lens which are sequentially arranged from an object plane to an image plane along an optical axis. The first lens, the second lens, the third lens, the fifth lens and the sixth lens all have positive focal power, and the fourth lens and the seventh lens all have negative focal power; the focal lengths of the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens and the seventh lens are f1, f2, f3, f4, f5, f6 and f7 respectively, and the focal length of the optical lens is f; wherein 11 < f1 / f < 12, 2.9 < f2 / f < 3.2, 3.8 < f3 / f < 4.0, 3.5 lt; f4 / flt; 4.0, 2.2 lt, 4.0, 2.2 lt; f5 / flt; 2.8, 2.8 lt, 2.8 lt; f6 / flt; 3.2, 2.2 lt, 3.2, 2.2 lt; f7 / flt; and 2.7. By adopting the technical scheme, the imaging quality is improved, and the high-definition image quality requirement is met.

Description

TECHNICAL FIELD

[0001] The embodiment of the utility model relates to optical imaging technical field, especially optical lens and automatic guided transport vehicle. BACKGROUND

[0002] With the development of science and technology, robots gradually replace human heavy work is the trend, wisdom logistics will become the future of the Internet of Things necessary in the big connection.

[0003] In some wisdom logistics scenarios, the automatic guided transport vehicle (AGV) provided with a camera can be applied in unmanned warehouses, wherein the camera is used for image information collection. The light in the unmanned warehouse environment is relatively dark, and the camera needs to work at a distance close enough, with a large enough field of view, and the product size is small and flexible to install, and it is also best to work stably in a certain high temperature environment.

[0004] The existing optical lens generally has the problems of uncorrected optical distortion, difficult correction, small aperture number of wide-angle lens, small amount of light, low image brightness, and defocus in high and low temperature. Therefore, it is urgent to design an optical lens with high imaging performance and small size. UTILITY MODEL CONTENT

[0005] The utility model provides a kind of optical lens and automatic guided transport vehicle to improve imaging quality, satisfy high-definition image quality demand.

[0006] In the first aspect, the utility model embodiment provides an optical lens, which comprises first lens, second lens, third lens, fourth lens, fifth lens, sixth lens and seventh lens arranged in order along optical axis from object plane to image plane;Wherein, the first lens, the second lens, the third lens, the fifth lens and the sixth lens are all positive focal length lens, and the fourth lens and the seventh lens are all negative focal length lens;

[0007] 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, the focal length of the sixth lens is f6, and the focal length of the seventh lens is f7. The focal length of the optical lens is f;Wherein, 11<|f1 / f|<12, 2.9<|f2 / f|<3.2, 3.8<|f3 / f|<4.0, 3.5<|f4 / f|<4.0, 2.2<|f5 / f|<2.8, 2.8<|f6 / f|<3.2, 2.2<|f7 / f|<2.7.

[0008] Optionally, the total length from the object side of the first lens to the image plane is s;The focal length of the optical lens is f;

[0009] wherein 10.5<|s / f|<11.

[0010] Optionally, an image height of the optical system is h; and a focal length of the optical lens is f.

[0011] wherein 3.0<|h / f|<3.5.

[0012] Optionally, the object side surface of the first lens is a convex surface, and the image side surface of the first lens is a concave surface; the object side surface of the second lens is a convex surface, and the image side surface of the second lens is a concave surface; the object side surface of the third lens is a concave surface, and the image side surface of the third lens is a concave surface; the object side surface of the fourth lens is a convex surface, and the image side surface of the fourth lens is a concave surface; the object side surface of the fifth lens is a convex surface, and the image side surface of the fifth lens is a convex surface; the object side surface of the sixth lens is a concave surface, and the image side surface of the sixth lens is a concave surface; and the object side surface of the seventh lens is a convex surface, and the image side surface of the seventh lens is a convex surface.

[0013] Optionally, an effective thickness of the fourth lens is t4; and a total length from the object side surface of the first lens to the image side surface is s.

[0014] wherein 0.1<|t4 / s|<0.15.

[0015] Optionally, the first lens and the fifth lens are glass spherical lenses.

[0016] The second lens, the third lens, the fourth lens, the sixth lens and the seventh lens are plastic aspherical lenses.

[0017] Optionally, a maximum effective diameter of the second lens is d2; and a total length from the object side surface of the first lens to the image side surface is s.

[0018] wherein 0.45<|d2 / s|<0.5.

[0019] Optionally, the optical lens further comprises a diaphragm.

[0020] The diaphragm is located between the fourth lens and the fifth lens; an aperture of the diaphragm is F; wherein 1.65≤F≤1.67.

[0021] Optionally, a refractive index temperature coefficient of the fifth lens is dn5 / dt; wherein 5*10 -6 <|dn5 / dt|<7.5*10 -6 .

[0022] In a second aspect, the utility model embodiment further provides an automatic guided vehicle, comprising the optical lens of any embodiment of the utility model.

[0023] The utility model discloses a through rationally setting the lens quantity in fixed focus lens, the refractive power of each lens can guarantee the balance of the incident angle size of fixed focus lens front and rear group lens under the premise of low cost, reduce the sensitivity of lens, improve the possibility of production, through the focal length of each lens and the focal length relation of optical lens of isolated setting, can correct optical distortion, realize low distortion to improve the imaging definition, thereby improve the imaging quality, satisfy the demand of high definition image quality. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 It is a kind of optical lens structure schematic diagram provided by the utility model embodiment;

[0025] Figure 2 It is a kind of optical modulation function diagram provided by the utility model embodiment;

[0026] Figure 3 It is the lens field curvature and optical distortion diagram of a kind of optical lens provided by the utility model embodiment;

[0027] Figure 4 It is the vertical axis chromatic aberration diagram of a kind of optical lens provided by the utility model embodiment;

[0028] Figure 5 It is the axial chromatic aberration diagram of a kind of optical lens provided by the utility model embodiment;

[0029] Figure 6 It is the optical modulation function & field diagram of a kind of optical lens provided by the utility model embodiment, in the diagram;

[0030] Figure 7 It is the chief ray angle diagram of a kind of optical lens provided by the utility model embodiment;

[0031] Figure 8 It is the relative luminance diagram of a kind of optical lens provided by the utility model embodiment;

[0032] Figure 9 It is another kind of optical modulation function diagram provided by the utility model embodiment;

[0033] Figure 10 It is another kind of optical modulation function diagram provided by the utility model embodiment. DETAILED DESCRIPTION

[0034] The utility model will be further explained in detail in combination with the drawings and embodiment.It can be understood that the specific embodiment described here is only used to explain the utility model, and is not limited to the utility model.In addition, it needs to be explained that, for the convenience of description, only the part related to the utility model is shown in the drawing, not all structures.

[0035] Figure 1 is a structural schematic diagram of an optical lens, as Figure 1 indicated, the optical lens comprises, in sequence along an optical axis from an object plane to an image plane, a first lens G1, a second lens G2, a third lens G3, a fourth lens G4, a fifth lens G5, a sixth lens G6 and a seventh lens G7; wherein the first lens G1, the second lens G2, the third lens G3, the fifth lens G5 and the sixth lens G6 are all positive power lenses, and the fourth lens G4 and the seventh lens G7 are both negative power lenses;

[0036] The focal length of the first lens G1 is f1, the focal length of the second lens G2 is f2, the focal length of the third lens G3 is f3, the focal length of the fourth lens G4 is f4, the focal length of the fifth lens G5 is f5, the focal length of the sixth lens G6 is f6, the focal length of the seventh lens G7 is f7, and the focal length of the optical lens is f; wherein 11<|f1 / f|<12, 2.9<|f2 / f|<3.2, 3.8<|f3 / f|<4.0, 3.5<|f4 / f|<4.0, 2.2<|f5 / f|<2.8, 2.8<|f6 / f|<3.2, and 2.2<|f7 / f|<2.7.

[0037] Wherein, the optical power is equal to the difference between the image beam convergence degree and the object beam convergence degree, which represents the ability of the optical system to deflect light. The greater the absolute value of the optical power, the stronger the bending ability of the light, and the smaller the absolute value of the optical power, the weaker the bending ability of the light. When the optical power is positive, the refraction of the light is convergent; when the optical power is negative, the refraction of the light is divergent. The optical power can be applied to characterize a certain refractive surface of a lens (i.e. a surface of the lens), a certain lens, or a system formed by multiple lenses (i.e. a lens group). In an optional embodiment, the lenses (G1, G2, G3, G4, G5, G6, G7) in the optical lens provided in the embodiment can be fixed in a lens barrel (not shown). Figure 1

[0038] Specifically, the first lens G1 is a negative power lens, which can be used to control the incidence angle of the optical system and correct the field curvature; the second lens G2 is a negative power lens, which can be used to correct off-axis aberration; the optical power of the third lens G3 is opposite to that of the seventh lens G7, the optical power of the fourth lens G4 is opposite to that of the sixth lens G6, and the fifth lens G5 is a positive power lens, which can be used to correct axial aberration and / or off-axis aberration, including field curvature, distortion, chromatic aberration and other aberrations. The optical power of the entire fixed focus lens is distributed in a certain proportion, which can ensure the balance of the incidence angle of the front and rear lens groups, reduce the sensitivity of the lens, improve the production possibility, in other words, improve the production stability and reliability of the lens, thereby improving the product yield.​

[0039] In addition, by reasonably distributing the focal lengths of the lenses (G1, G2, G3, G4, G5, G6, G7), the spherical aberration and the field curvature of the imaging system can be small, and the on-axis and off-axis field image quality can be ensured. The optical system composed of the above lenses (G1, G2, G3, G4, G5, G6, G7) has a short total optical path length, thereby ensuring that the overall size of the lens is small.

[0040] In an optional embodiment, the focal length f of the optical lens is 2.12 mm, and the relative relationship between the focal length of each lens and the focal length f of the optical lens at room temperature 25℃ can be as shown in Table 1.

[0041] Table 1 Relative relationship between focal length of each lens and focal length f of optical lens

[0042] | f1 / f | | f2 / f | | f3 / f | | f4 / f | | f5 / f | | f6 / f | | f7 / f | 11.31 3.11 3.96 3.83 2.49 2.90 2.41

[0043] Exemplarily, Figure 2 is an optical modulation function (Modulation Transfer Function, MTF) provided by the embodiment of the utility model, the MTF is defined by spatial frequency and contrast, which represents the ability of the optical system to transfer contrast, wherein, Figure 2 is an MTF provided by the optical lens of the embodiment of the utility model under the environment of room temperature 25℃. In the figure, the abscissa is spatial frequency (lp / mm), and the ordinate is normalized contrast (OTF modulus).

[0044] Wherein, the spatial frequency (lp / mm) represents the black and white line pairs per millimeter, and the higher the spatial frequency (lp / mm), the more black and white line pairs per millimeter; the contrast is a normalized value, the higher the contrast, the clearer the image observed by the naked eye, the lower the contrast, the more blurred the image observed by the naked eye, and the contrast will decrease when the spatial frequency (lp / mm) increases. Generally speaking, when the normalized contrast is 0.3 or above, a relatively clear image can be observed.

[0045] Figure 2 In the embodiment, the different colors represent different fields of view (half angles) at the center and periphery, and each color has two curves, representing the meridian (vertical axis) image and the sagittal (axial) image. The MTF value in the range of object distance greater than 1000mm is the contrast under different fields of view when the spatial frequency (lp / mm) reaches 150 lp / mm, which can reach above 0.3, and a relatively clear image can be observed. Therefore, the optical lens provided by the embodiment has better clarity under different fields of view, and the image detail restoration degree is higher.

[0046] Exemplarily, Figure 3The left graph is a field curvature graph of the optical lens, wherein the horizontal coordinate is a field curvature value of a visible light wavelength, and the vertical coordinate is a field angle (half angle); the middle solid line (the solid line with a horizontal coordinate of zero) can represent an ideal image surface; the right graph is an optical distortion graph of the optical lens, wherein the horizontal coordinate is a distortion percentage of the visible light wavelength, and the vertical coordinate is the field angle; the middle solid line (the solid line with a horizontal coordinate of zero) can represent the ideal image surface.

[0047] The field curvature (Curvature of Field), also known as image field curvature, refers to that when a planar object is imaged by a lens system, although each object point can form a clear image point behind the lens, the image points are not coplanar but form a curved surface; the greater the field curvature value is, the greater the position offset of the edge light and the central light after focusing through the lens is, and the image surface presents a curved state. The distortion refers to the deformation between the actual image surface and the ideal image surface when an object is imaged by a lens; the deformation is caused by the different local magnification ratios, so that the object and the image are not completely scaled at a constant ratio, and the deformation is the distortion.

[0048] Figure 3 In the graph, different colors represent different color light rays of different wavelengths, and each color has two curves, which represent the meridian (vertical axis) image and the sagittal (axial) image. Figure 3 It can be seen that when the field angle (half angle) is 0-60°, the optical distortion is less than 10%, and the image position point has a high degree of restoration; the optical lens provided by the embodiment has a good correction of the distortion, small imaging distortion, and meets the requirement of low distortion.

[0049] The optical lens provided by the embodiment of the utility model, by reasonably setting the number of lenses in the fixed focus lens and the optical power of each lens, can ensure the balance of the incident angle size of the front and rear group lenses of the fixed focus lens under the premise of low cost, reduce the sensitivity of the lens, and improve the possibility of production; by isolating the focal length of each lens and the focal length relationship of the optical lens, the optical distortion can be corrected, the low distortion is realized, the imaging clarity is improved, the imaging quality is improved, and the high-definition image quality requirement is met.

[0050] Optionally, the total length from the object side to the image side of the first lens G1 is s; the focal length of the optical lens is f; wherein 10.5<|s / f|<11. By reasonably setting the relationship between the total length s from the object side to the image side of the first lens G1 and the focal length f of the optical lens, the higher image quality can be realized while ensuring a smaller size.

[0051] In an optional embodiment, the total track length (TTL) of the optical lens can be less than 22.5mm, so that the product has a size advantage.

[0052] Optionally, the image height of the optical system is h, and the focal length of the optical lens is f, wherein 3.0<|h / f|<3.5.

[0053] Optionally, the refractive index of the first lens G1 is n1, and 1.75<|n1|<1.85.

[0054] Specifically, the refractive index of the first lens G1 is relatively large, and the deflection ability of light is stronger, so that the size of the first lens G1 can be smaller, thereby facilitating the reduction of the aperture of a lens barrel (not shown in the figure) of the optical lens, and the axial chromatic aberration can be effectively corrected.

[0055] Exemplarily, Figure 4 is an axial chromatic aberration diagram of the optical lens provided by the embodiment of the present application, in which the abscissa is a dimensional value, the unit is μm, the ordinate is a field angle value, and the middle solid line (the solid line with the abscissa of zero) can represent an ideal image surface.

[0056] The axial chromatic aberration is because different wavelengths of light form different heights of focal points in the axial direction after being focused by the lens, which is equivalent to different magnifications of imaging, and the axial chromatic aberration can also be called a magnification chromatic aberration or a defocus amount. In the imaging effect, the focal points of different wavelengths will be arranged in sequence in the height direction, and a rainbow edge band is generated at the edge. Under a large viewing angle, the smaller the absolute value of the dimensional value is, the smaller the axial chromatic aberration is, and the better the imaging performance is.

[0057] Figure 4 In the diagram, different colors represent different color light rays of different wavelengths, and Figure 4 It can be seen that the axial chromatic aberration of the optical lens provided by the embodiment is less than 15 μm when the maximum field angle (half angle) is 60°, the axial chromatic aberration is small, and high-quality imaging effect can be achieved.

[0058] In an optional embodiment, the wear degree of the first lens is FA, and |FA|<100. In this way, the scratch damage in daily use can be effectively prevented.

[0059] In still another optional embodiment, the Abbe number of the fourth lens is Vd, and Vd<25. The positional chromatic aberration can be effectively corrected.

[0060] Exemplarily, Figure 5 is an axial chromatic aberration diagram of the optical lens provided by the embodiment of the present application, in which the abscissa is a dimensional value, the unit is μm, the ordinate is a field angle value, and the middle solid line (the solid line with the abscissa of zero) can represent an ideal image surface.

[0061] Wherein, the axial chromatic aberration can also be called the position chromatic aberration, which refers to the different wavelengths of light through the lens after the focal position is located at different positions along the axial direction. Because the polychromatic light will form multiple focal points after passing through the lens, thus resulting in that no matter where the image plane is placed, a clear light spot cannot be obtained. The smaller the absolute value of the dimensional value under different pupil coordinates, the smaller the axial chromatic aberration, and the better the imaging performance.

[0062] Figure 5 In the embodiment, different colors represent different color light rays of different wavelengths, and the Figure 5 It can be seen that the optical lens provided in the embodiment has the absolute value of the dimensional value less than 15 μm under different pupil coordinates, the sagittal chromatic aberration is small, and high-quality imaging effect is beneficial to be realized.

[0063] Optionally, continuing to refer to Figure 1 The object side surface of the first lens G1 is a convex surface, and the image side surface is a concave surface; the object side surface of the second lens G2 is a convex surface, and the image side surface is a concave surface; the object side surface of the third lens G3 is a concave surface, and the image side surface is a concave surface; the object side surface of the fourth lens G4 is a convex surface, and the image side surface is a concave surface; the object side surface of the fifth lens G5 is a convex surface, and the image side surface is a convex surface; the object side surface of the sixth lens G6 is a concave surface, and the image side surface is a concave surface; and the object side surface of the seventh lens G7 is a convex surface, and the image side surface is a convex surface.

[0064] Specifically, the first lens G1, the second lens G2 and the fourth lens G4 can be meniscus structures, the third lens G3 can be a double-concave structure, the fifth lens G5 and the seventh lens G7 can be double-convex structures, and the sixth lens G6 can be a double-concave structure. By reasonably setting the surface shapes of the lenses, the optical power of the optical system can be reasonably distributed, so that the light rays are better transmitted to ensure the imaging quality; and the compact structure of the entire optical lens can be ensured, which is beneficial to improve the integration of the optical lens, thereby reducing the size of the product and facilitating flexible installation.

[0065] On the basis of the above embodiment, the effective thickness (central thickness) of the fourth lens G4 is t4; and the total length from the object side surface to the image side surface of the first lens G1 is s; wherein 0.1 < |t4 / s| < 0.15. The lens shape of the fourth lens G4 is a meniscus thick lens, which can effectively correct the field curvature.

[0066] Optionally, the first lens G1 and the fifth lens G5 are glass spherical lenses; and the second lens G2, the third lens G3, the fourth lens G4, the sixth lens G6 and the seventh lens G7 are plastic aspherical lenses.

[0067] Wherein, the aspherical conic coefficient equation z of the second lens G2, the third lens G3, the fourth lens G4, the sixth lens G6 and the seventh lens G7 satisfies but is not limited to:

[0068]

[0069] In the formula, z is the axial distance of the curved surface to the vertex at a position along the optical axis and perpendicular to the optical axis with a height of h; c represents the curvature at the vertex of the aspherical surface; k is the conic coefficient; A4, A6, A8, A 10 , A 12 , A 16 , A 10 , A 12 , A 14 , and A 16 represent the fourth-order, sixth-order, eighth-order, tenth-order, twelfth-order, fourteenth-order, sixteenth-order, and so on aspherical surface coefficients, respectively.

[0070] For example, Table 2 details the aspherical surface coefficients of the optical lens according to an embodiment of the present application, which includes a quadratic surface constant K, a fourth-order aspherical surface coefficient A4, a sixth-order aspherical surface coefficient A6, an eighth-order aspherical surface coefficient A8, a tenth-order aspherical surface coefficient A 10 , a twelfth-order aspherical surface coefficient A 12 , a fourteenth-order aspherical surface coefficient A 14 , and a sixteenth-order aspherical surface coefficient A 16 .

[0071] Table 2: Design values of aspherical surface coefficients in the optical lens

[0072]

[0073] In the formula, -2.88E-05 represents that the coefficient A4 numbered as “S3” is -2.88*10 -5 , and so on.

[0074] For example, Figure 6 is an MTF&field of view diagram of the optical lens according to an embodiment of the present application, in which the horizontal coordinate is the lens field of view angle (half angle) value, and the vertical coordinate is the normalized contrast, wherein the eight different colors respectively represent spatial frequencies of 80 lp / mm, 100 lp / mm, 120 lp / mm, and 160 lp / mm, the solid line represents the meridional direction, and the dashed line represents the sagittal direction. In an embodiment, Figure 6 is an MTF&field of view diagram of the optical lens according to an embodiment of the present application under a room temperature 25℃ environment.

[0075] It can be known that the MTF value is the contrast under different spatial frequencies (lp / mm) when the field of view angle (half angle) is 60°, which can still reach above 0.3, and a relatively clear image can be observed. It can be known that the diagonal field of view angle (full angle) of the optical lens according to the embodiment can reach 120°, and a relatively high definition can be ensured under a relatively large field of view, and the image detail restoration degree is relatively high. Figure 6 For example,

[0076] Figure 7The utility model embodiment provides a kind of chief ray angle (chiefray angle, CRA) diagram of optical lens, in the drawing, abscissa is normalized image height, ordinate is chief ray angle value.Wherein, chief ray angle value refers to the angle of the central light of a certain field of view imaging beam and optical axis, central light is the light of the aperture diaphragm center of this field of view, i.e. Figure 7 It is known that the maximum chief ray angle is less than 13°, and the image plane can reach φ6.6mm, which is beneficial to reduce optical distortion and increase the field of view.

[0077] In this way, by reasonably matching the spherical lens and the aspherical lens, various aberrations in the optical system can be corrected, thereby improving the resolution of the lens. Moreover, two glass spherical lenses and five aspherical lenses are used, the number of spherical lenses is small, and the proportion of aspherical lenses is large, which is beneficial to low-cost optical lenses. In addition, using two glass spherical lenses (G1, G5), the diagonal field of view angle (full angle) can reach 120°, the maximum image plane is greater than φ6.6mm, and the maximum supported image plane is 7.0mm. On the one hand, it can match a large-sized image sensor, which is beneficial to increase the field of view. On the other hand, the large image plane diameter is beneficial to shorten the TTL of the optical lens, for example, the TTL can be less than 22.5mm, which can make the product smaller and have a size advantage.

[0078] On the basis of the above embodiment, the maximum effective diameter of the second lens G2 is d2, and the total length from the object side of the first lens G1 to the image plane is s, wherein 0.45 < |d2 / s| < 0.5.

[0079] Specifically, the second lens G2 is an aspherical lens. By setting the maximum effective diameter d2 of the second lens to be relatively large, the distortion of the optical system can be effectively limited, and the distortion can be corrected.

[0080] Optionally, referring back to Figure 1 , the optical lens further includes a stop STO; the stop STO is located between the fourth lens G4 and the fifth lens G5; the aperture of the stop STO is F; wherein 1.65 ≤ F ≤ 1.67.

[0081] Specifically, the stop STO is placed in the middle, which is beneficial to reduce aberration and improve image quality; the aperture F of the stop STO is in the range of 1.65-1.67, which is beneficial to increase the amount of light entering the optical lens, so that the optical lens can be applicable to a relatively dark environment. In an optional embodiment, the aperture F of the stop STO is 1.66.

[0082] Illustratively, Figure 8is a relative luminance diagram of an optical lens provided by the embodiment of the utility model, in the diagram, the abscissa is the field angle (half angle) value, and the ordinate is the normalized relative luminance value. Among them, the light degree shown on the object or the illuminated surface by the light source is called the illumination, and the relative luminance is the ratio of the center illumination and the peripheral illumination. The relative luminance is too low to show that the image center is brighter, and the periphery is darker, that is, the vignetting phenomenon, commonly known as the dark corner, and the relative luminance is too low to cause color distortion. By Figure 8 It can be known that when the field angle is 60°, the relative luminance is greater than or equal to 0.45, that is, when the field angle is 60°, the relative luminance is greater than 45%, which indicates that the image edge brightness and the image brightness are relatively small, and the optical lens provided by the embodiment of the utility model can be applied to a relatively dark environment.

[0083] Optionally, the refractive index of the fifth lens G5 is n5, wherein n5 < 1.45, which is conducive to reducing the dispersion of the optical lens.

[0084] Optionally, the refractive index temperature coefficient (D wavelength 587nm) of the fifth lens G5 is between-30℃-70℃, and satisfies 5*10 -6 <|dn / dt|<7.5*10 -6 , which can reduce the defocus amount caused by temperature change, compensate for the image shift caused by temperature change, and make the optical system better realize athermalization.

[0085] Exemplarily, Table 3 is the optical parameters of each lens of the optical system at a first group temperature of 25°, including the curvature radius (unit: mm), the thickness of each lens at the first group temperature of 25℃ (unit: mm), the thickness of each lens at the second group temperature of-30℃ (unit: mm), the thickness of each lens at the third group temperature of 70℃ (unit: mm), the refractive index, and the Abbe number.

[0086] Table 3 is one design value of the optical parameters of each lens in the optical lens

[0087] Surface Radius of curvature Thickness @ 25° Thickness @ -30° Thickness @ 70° Refractive index Abbe number Object plane Infinite 3000 3000 3000 S1 11.71 0.900 0.900 0.900 1.80 46.6 S2 7.04 0.152 0.129 0.171 S3 5.43 0.850 0.847 0.852 1.54 55.7 S4 2.02 4.095 4.107 4.085 S5 -5.58 1.848 1.842 1.854 1.54 55.7 S6 25.75 0.487 0.490 0.484 S7 4.40 2.858 2.847 2.867 1.66 20.4 S8 17.91 0.208 0.208 0.208 STO Infinite 0.557 0.557 0.558 S10 8.19 2.295 2.293 2.297 1.44 94.6 S11 -2.94 0.096 0.098 0.094 S12 -4.97 0.695 0.693 0.697 1.66 20.4 S13 23.40 0.139 0.137 0.140 S14 6.37 2.302 2.294 2.308 1.54 55.7 S15 -4.18 4.300 4.300 4.300 S16 Infinite 0.700 0.700 0.700 1.52 64.2 S17 Infinite 0.015 0.000 0.028 Image plane

[0088] It can be known from Table 3 that compared with the lens thickness in the room temperature 25℃ environment, the deviation of the lens thickness in the-30℃ environment and the 70℃ environment is within ±0.015mm, the thickness of each lens changes little in the high-temperature and low-temperature environments, so that the defocus amount of each lens in the high-temperature and low-temperature environments is small, and the optical lens provided by the embodiment can still clearly image in the high-temperature and low-temperature environments.

[0089] Figure 9 is another MTF diagram provided by the embodiment of the utility model, Figure 9The MTF graph of the optical lens under a 70 DEG C environment, in which, the horizontal coordinate is spatial frequency (lp / mm), and the vertical coordinate is normalized contrast. Figure 10 The MTF graph of the optical lens under a 70 DEG C environment, in which, the horizontal coordinate is spatial frequency (lp / mm), and the vertical coordinate is normalized contrast. Figure 10 The MTF graph of the optical lens under a 70 DEG C environment, in which, the horizontal coordinate is spatial frequency (lp / mm), and the vertical coordinate is normalized contrast. As shown in Figure 2 、 Figure 9 and Figure 10 indicated, under different temperature environments, the MTF value in the range of object distance greater than 1000mm is 150lp / mm when the spatial frequency (lp / mm) reaches 150lp / mm, the contrast under different fields of view can almost reach above 0.3, and a clearer image can be observed, so that it can be known that the optical lens provided in the embodiment can work without defocus in high and low temperature environments, and can clearly image in the high and low temperature environments.

[0090] Based on the same idea, the utility model embodiment still provides a kind of automated guided vehicle, and the automated guided vehicle includes the optical lens provided in any embodiment of the utility model.The automated guided vehicle provided in the utility model embodiment can be any car that can reach specified place according to set route, for example, automated guided vehicle can be loaded goods in automatic or manual mode, can directly transport goods, or also can transport goods by the mode of driving load platform car, and the utility model embodiment is not specially limited to this.

[0091] The automated guided vehicle provided in the utility model embodiment includes the optical lens provided in any embodiment of the utility model, has the corresponding technical features and beneficial effects of optical lens, and the content not described in detail in the embodiment of automated guided vehicle can be referred to the description of optical lens above, and will not be repeated here.

[0092] Note that the above is only the preferred embodiment of the utility model and the technical principle applied.The person skilled in the art will understand that the utility model is not limited to the specific embodiments described herein, and those skilled in the art can make various obvious changes, re-adjustment, mutual combination and replacement without departing from the protection scope of the utility model. Therefore, although the utility model is more specifically described through the above embodiments, the utility model is not limited to the above embodiments, and can include more other equivalent embodiments without departing from the concept of the utility model, and the scope of the utility model is determined by the appended claims.

Claims

1. An optical lens characterized in that, The optical lens comprises, in sequence from an object plane to an image plane along an optical axis, a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens and a seventh lens; wherein the first lens, the second lens, the third lens, the fifth lens and the sixth lens are positive focal power lenses, and the fourth lens and the seventh lens are negative focal power lenses. A focal length of the first lens is f1, a focal length of the second lens is f2, a focal length of the third lens is f3, a focal length of the fourth lens is f4, a focal length of the fifth lens is f5, a focal length of the sixth lens is f6, a focal length of the seventh lens is f7, and a focal length of the optical lens is f; wherein 11<|f1 / f|<12, 2.9<|f2 / f|<3.2, 3.8<|f3 / f|<4.0, 3.5<|f4 / f|<4.0, 2.2<|f5 / f|<2.8, 2.8<|f6 / f|<3.2, and 2.2<|f7 / f|<2.

7.

2. The optical lens of claim 1, wherein, A total length of an object side surface to an image side surface of the first lens is s; and a focal length of the optical lens is f. Wherein 10.5<|s / f|<11.

3. The optical lens of claim 1, wherein, An image height of the optical system is h; and a focal length of the optical lens is f. Wherein 3.0<|h / f|<3.

5.

4. The optical lens of claim 1, wherein, An object side surface of the first lens is a convex surface, and an image side surface thereof is a concave surface; an object side surface of the second lens is a convex surface, and an image side surface thereof is a concave surface; an object side surface of the third lens is a concave surface, and an image side surface thereof is a concave surface; an object side surface of the fourth lens is a convex surface, and an image side surface thereof is a concave surface; an object side surface of the fifth lens is a convex surface, and an image side surface thereof is a convex surface; an object side surface of the sixth lens is a concave surface, and an image side surface thereof is a concave surface; and an object side surface of the seventh lens is a convex surface, and an image side surface thereof is a convex surface.

5. The optical lens of claim 4, wherein, An effective thickness of the fourth lens is t4; and a total length of an object side surface to an image side surface of the first lens is s. Wherein 0.1<|t4 / s|<0.

15.

6. The optical lens of claim 1, wherein, The first lens and the fifth lens are glass spherical lenses. The second lens, the third lens, the fourth lens, the sixth lens and the seventh lens are plastic aspherical lenses.

7. The optical lens of claim 6, wherein, A maximum effective diameter of the second lens is d2; and a total length of an object side surface to an image side surface of the first lens is s. Wherein 0.45<|d2 / s|<0.

5.

8. The optical lens of claim 1, wherein, The optical lens further comprises a diaphragm. The diaphragm is located between the fourth lens and the fifth lens; an aperture of the diaphragm is F; wherein 1.65≤F≤1.

67.

9. The optical lens of claim 8, wherein, The temperature coefficient of the refractive index of the fifth lens is dn5 / dt; wherein, 5*10 -6 |dn5 / dt|<7.5*10 -6 .

10. An automated guided vehicle, characterized by The optical lens comprises the optical lens according to any one of claims 1-9.

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