Projection optical lens and projection optical system

Abstract

The utility model discloses a kind of projection optical lens and projection optical system, it is related to projection lens technical field, wherein, including first lens, second lens, third lens, fourth lens, fifth lens, sixth lens, seventh lens, eighth lens, ninth lens and emitting light chip sequentially arranged from object side to image side along optical axis, the refractive power of first lens, second lens, fifth lens, seventh lens is negative, the refractive power of remaining lens is positive;Wherein, first lens, second lens are plastic aspheric lens, third lens, fourth lens, fifth lens, sixth lens, seventh lens, eighth lens and ninth lens are glass spherical lens, the aperture value F of projection optical lens is less than or equal to 2.0;The lens of utility model provides, and picture brightness is high, by different lens mutual combination and reasonable allocation refractive power, with low cost, high brightness and very good abenign performance, picture is brighter, projection effect is better.

Description

Technical Field

[0001] This utility model relates to the field of projection lens technology, and in particular to a projection optical lens and a projection optical system. Background Technology

[0002] With the development of projection technology, projectors are increasingly widely used in education, medical care, and home use. People have higher and higher requirements for projectors. As the core component of projectors, the requirements for various parameters of the lens are also increasing. However, the aperture of projector lenses on the market is generally small, which results in low brightness of the projected image during the day, affecting daily use. In order to increase the aperture, some projector lenses use more spherical lenses or glass aspherical lenses, which makes them expensive.

[0003] In related technologies, plastic aspherical lenses are used in projector lenses to reduce costs. However, due to the high heat generated by projectors, these lenses often experience defocusing due to high temperatures.

[0004] Therefore, how to increase the aperture, reduce costs, and avoid high-temperature defocusing has become an urgent problem to be solved in this field. Utility Model Content

[0005] The main purpose of this invention is to propose a projection optical lens and projection optical system, which aims to increase the aperture of the projector lens, reduce costs, and avoid high-temperature defocusing.

[0006] To achieve the above objectives, the projection optical lens proposed in this utility model has an image side and an object side arranged opposite to each other along the optical axis. The projection optical lens includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, an eighth lens, a ninth lens, and a light-emitting chip arranged sequentially along the optical axis from the object side to the image side. The first lens has a negative optical power, the second lens has a negative optical power, the third lens has a positive optical power, the fourth lens has a positive optical power, the fifth lens has a negative optical power, the sixth lens has a positive optical power, the seventh lens has a negative optical power, the eighth lens has a positive optical power, and the ninth lens has a positive optical power. The first and second lenses are plastic aspherical lenses, and the third, fourth, fifth, sixth, seventh, eighth, and ninth lenses are glass spherical lenses. The aperture value of the projection optical lens is F≤2.0.

[0007] In one embodiment, the object side of the first lens is convex and the image side is concave. The focal length of the first lens is f1, and f1 satisfies: -30 mm < f1 < -15 mm; the object side of the second lens is concave and the image side is convex. The focal length of the second lens is f2, and f2 satisfies: -50 mm < f2 < -30 mm; the object side of the third lens is concave and the image side is convex. The focal length of the third lens is f3, and f3 satisfies: 100 mm < f3 < 200 mm; the object side of the fourth lens is convex and the image side is convex. The focal length of the fourth lens is f4, and f4 satisfies: 20 mm < f4 < 35 mm; the object side of the fifth lens is convex and the image side is concave. The focal length of the fifth lens is f5, and f5 satisfies: -25 mm < f5 < -10 mm; the object side of the sixth lens is convex and the image side is convex. The focal length of the sixth lens is f6, and f6 satisfies: 10 mm < f6 < 20 mm; the object side of the seventh lens is concave and the image side is convex. The focal length of the seventh lens is f7, and f7 satisfies: -25 mm < f7 < -10 mm; the object side of the eighth lens is convex and the image side is convex. The focal length of the eighth lens is f8, and f8 satisfies: 25 mm < f8 < 40 mm; the object side of the ninth lens is convex and the image side is convex. The focal length of the ninth lens is f9, and f9 satisfies: 25 mm < f9 < 40 mm.

[0008] In one embodiment, the refractive index n1 and the dispersion coefficient v1 of the first lens satisfy: 1.50 ≤ n1 ≤ 1.60; 50.0 ≤ v1 ≤ 60.0; the refractive index n2 and the dispersion coefficient v2 of the second lens satisfy: 1.50 ≤ n2 ≤ 1.60; 50.0 ≤ v2 ≤ 60.0; the refractive index n3 and the dispersion coefficient v3 of the third lens satisfy: 1.45 ≤ n3 ≤ 1.55; 65.0 ≤ v3 ≤ 95.0; the refractive index n4 and the dispersion coefficient v4 of the fourth lens satisfy: 1.75 ≤ n4 ≤ 1.95; 30.0 ≤ v4 ≤ 55.0; the refractive index n5 and the dispersion coefficient v5 of the fifth lens satisfy: 1.75 ≤ n5 ≤ 1.95; 20.0 ≤ v5 ≤ 35.0; the refractive index n6 and the dispersion coefficient v6 of the sixth lens satisfy: 1.45 ≤ n6 ≤ 1.60; 75.0 ≤ v6 ≤ 95.0; the refractive index n7 and the dispersion coefficient v7 of the seventh lens satisfy: 1.75 ≤ n7 ≤ 1.95; 20.0 ≤ v7 ≤ 35.0; the refractive index n8 and the dispersion coefficient v8 of the eighth lens satisfy: 1.40 ≤ n8 ≤ 1.60; 75.0 ≤ v8 ≤ 95.0; the refractive index n9 and the dispersion coefficient v9 of the ninth lens satisfy: 1.75 ≤ n9 ≤ 1.95; 20.0 ≤ v9 ≤ 35.0.

[0009] In one embodiment, the diameter D1 of the first lens satisfies: D1≤30mm.

[0010] In one embodiment, the light-emitting chip has a light-emitting surface close to the ninth lens, and the diameter IC of the light-emitting surface satisfies: IC≤13.5mm.

[0011] In one embodiment, the effective focal length of the projection optical lens is EFL, the light-emitting chip has a light-emitting surface close to the ninth lens, and the distance TTL between the object-side vertex of the first lens and the light-emitting surface satisfies: TTL / EFL≤9.

[0012] In one embodiment, both the first lens and the second lens are even-order aspherical lenses.

[0013] In one embodiment, the fifth lens, the sixth lens, and the seventh lens form an adhesive lens group.

[0014] In one embodiment, a prism is disposed between the light-emitting chip and the ninth lens.

[0015] This utility model also proposes a projection optical system using the projection optical lens described above; the projection optical lens includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, an eighth lens, a ninth lens, and a light-emitting chip arranged sequentially along the optical axis from the object side to the image side. The first lens has a negative optical power, the second lens has a negative optical power, the third lens has a positive optical power, the fourth lens has a positive optical power, the fifth lens has a negative optical power, the sixth lens has a positive optical power, the seventh lens has a negative optical power, the eighth lens has a positive optical power, and the ninth lens has a positive optical power; wherein, the first lens and the second lens are plastic aspherical lenses, and the third lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens, the eighth lens, and the ninth lens are glass spherical lenses.

[0016] The technical solution of this utility model has a large light transmission capacity and high image brightness. By combining different lenses and rationally allocating the optical power, it has the performance of low cost, high brightness and very good heat dissipation, resulting in a brighter image and better projection effect. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0018] Figure 1 A schematic diagram of the structure of an embodiment of the projection optical lens provided by this utility model;

[0019] Figure 2 for Figure 1 A schematic diagram of the transverse chromatic aberration curve of a projection optical lens;

[0020] Figure 3 for Figure 1 A schematic diagram of the SPOT point of a projection optical lens;

[0021] Figure 4 for Figure 1 A schematic diagram of the MTF of a projection optical lens.

[0022] Explanation of icon numbers:

[0023] 100. Projection optical lens; 1. First lens; 2. Second lens; 3. Third lens; 4. Fourth lens; 5. Fifth lens; 6. Sixth lens; 7. Seventh lens; 8. Eighth lens; 9. Ninth lens; 10. Aperture; 11. Prism; 12. Light-emitting chip.

[0024] The realization of the purpose, functional features and advantages of this utility model will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0025] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present utility model.

[0026] It should be noted that if the embodiments of this utility model involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indicators will also change accordingly.

[0027] Furthermore, if the embodiments of this utility model involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the use of "and / or" or "and / or" throughout the text includes three parallel solutions. For example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this utility model.

[0028] With the development of projection technology, projectors are increasingly widely used in education, medical care, and home use. People have higher and higher requirements for projectors. As the core component of projectors, the requirements for various parameters of the lens are also increasing. However, the aperture of projector lenses on the market is generally small, which results in low brightness of the projected image during the day, affecting daily use. In order to increase the aperture, some projector lenses use more spherical lenses or glass aspherical lenses, which makes them expensive.

[0029] In related technologies, plastic aspherical lenses are used in projector lenses to reduce costs. However, due to the high heat generated by projectors, these lenses often experience defocusing due to high temperatures. To solve this problem, this utility model proposes a novel projector lens design. This design uses special materials and structures to effectively dissipate heat and maintain optical stability, ensuring clear imaging even in high-temperature environments, while reducing costs and improving user experience.

[0030] This utility model proposes a projection optical lens 100. Please refer to [link / reference]. Figure 1In one embodiment of this utility model, the projection optical lens 100 has an image side and an object side arranged opposite to each other along the optical axis. The projection optical lens 100 includes a first lens 1, a second lens 2, a third lens 3, a fourth lens 4, a fifth lens 5, a sixth lens 6, a seventh lens 7, an eighth lens 8, a ninth lens 9, and a light-emitting chip 12 arranged sequentially along the optical axis from the object side to the image side. The optical power of the first lens 1 is negative, the optical power of the second lens 2 is negative, the optical power of the third lens 3 is positive, the optical power of the fourth lens 4 is positive, the optical power of the fifth lens 5 is negative, the optical power of the sixth lens 6 is positive, the optical power of the seventh lens 7 is negative, the optical power of the eighth lens 8 is positive, and the optical power of the ninth lens 9 is positive. Among them, the first lens 1 and the second lens 2 are plastic aspherical lenses, and the third lens 3, the fourth lens 4, the fifth lens 5, the sixth lens 6, the seventh lens 7, the eighth lens 8, and the ninth lens 9 are plastic spherical lenses. The aperture value F of the projection optical lens 100 is ≤2.0.

[0031] The technical solution of this utility model has a large light transmission capacity and high screen brightness. By combining different lenses and rationally allocating the optical power, it has the performance of low cost, high brightness and very good heat dissipation, resulting in a brighter screen and better projection effect. Furthermore, by setting the first and second plastic aspherical lenses with negative optical power, the incident angle of light entering the optical system is controlled, which is beneficial for distortion correction, shortening the projection distance and increasing the projection ratio. It can also control the light path well, making the structure more compact while introducing more light, and keeping the total lens length within 60.7mm.

[0032]

[0033] Where Z represents the distance from the vertex of the surface along the optical axis, c is the curvature of the vertex of the surface; y is the distance from the optical axis to the surface; k is the conic coefficient (when the k coefficient is less than -1, the surface curve is a hyperbola; when the k coefficient is equal to -1, it is a parabola; when the k coefficient is between -1 and 0, it is an ellipse; when the k coefficient is equal to 0, it is a circle; when the k coefficient is greater than 0, it is an oval). A, B, C, D, E, F, and G represent the fourth, sixth, eighth, tenth, twelfth, fourteenth, and sixteenth order aspherical coefficients, respectively. The shape and size of the aspherical surfaces of the object side and image side of the lens can be set by using the above parameters.

[0034] Furthermore, an aperture stop 10 is provided between the fourth lens 4 and the fifth lens 5, which can further improve the imaging quality and reduce the interference of stray light.

[0035] In an embodiment of the present utility model, the object side of the first lens 1 is convex and the image side is concave. The focal length of the first lens 1 is f1, and f1 satisfies: -30 mm < f1 < -15 mm; the object side of the second lens 2 is concave and the image side is convex. The focal length of the second lens 2 is f2, and f2 satisfies: -50 mm < f2 < -30 mm; the object side of the third lens 3 is concave and the image side is convex. The focal length of the third lens 3 is f3, and f3 satisfies: 100 mm < f3 < 200 mm; the object side of the fourth lens 4 is convex and the image side is convex. The focal length of the fourth lens 4 is f4, and f4 satisfies: 20 mm < f4 < 35 mm; the object side of the fifth lens 5 is convex and the image side is concave. The focal length of the fifth lens 5 is f5, and f5 satisfies: -25 mm < f5 < -10 mm; the object side of the sixth lens 6 is convex and the image side is convex. The focal length of the sixth lens 6 is f6, and f6 satisfies: 10 mm < f6 < 20 mm; the object side of the seventh lens 7 is concave and the image side is convex. The focal length of the seventh lens 7 is f7, and f7 satisfies: -25 mm < f7 < -10 mm; the object side of the eighth lens 8 is convex and the image side is convex. The focal length of the eighth lens 8 is f8, and f8 satisfies: 25 mm < f8 < 40 mm; the object side of the ninth lens 9 is convex and the image side is convex. The focal length of the ninth lens 9 is f9, and f9 satisfies: 25 mm < f9 < 40 mm. Thus, by comprehensively setting the optical power and the cooperation relationship of the shapes of each lens, compactness and light weight can be achieved.

[0036] In one embodiment of this utility model, the refractive index n1 and dispersion coefficient v1 of the first lens 1 satisfy: 1.50≤n1≤1.60; 50.0≤v1≤60.0; the refractive index n2 and dispersion coefficient v2 of the second lens 2 satisfy: 1.50≤n2≤1.60; 50.0≤v2≤60.0; the refractive index n3 and dispersion coefficient v3 of the third lens 3 satisfy: 1.45≤n3≤1.55; 65.0≤v3≤95.0; the refractive index n4 and dispersion coefficient v4 of the fourth lens 4 satisfy: 1.75≤n4≤1.95; 30.0≤v4≤55.0; the refractive index n5 and dispersion coefficient v1 of the fifth lens 5 satisfy: 1.50≤n1≤1.60; 50.0≤v1≤60 ... The refractive index n6 and dispersion coefficient v6 of the sixth lens 6 satisfy the following conditions: 1.75≤n5≤1.95; 20.0≤v5≤35.0; the refractive index n6 and dispersion coefficient v6 of the seventh lens 7 satisfy the following conditions: 1.45≤n6≤1.60; 75.0≤v6≤95.0; the refractive index n7 and dispersion coefficient v7 of the seventh lens 7 satisfy the following conditions: 1.75≤n7≤1.95; 20.0≤v7≤35.0; the refractive index n8 and dispersion coefficient v8 of the eighth lens 8 satisfy the following conditions: 1.40≤n8≤1.60; 75.0≤v8≤95.0; the refractive index n9 and dispersion coefficient v9 of the ninth lens 9 satisfy the following conditions: 1.75≤n9≤1.95; 20.0≤v9≤35.0. By optimizing the refractive index and dispersion coefficient of each lens, and using lens combinations with different dispersion characteristics to correct chromatic aberration, light of different wavelengths can be focused on the same plane, reducing color edge blurring, improving image detail and clarity, and ensuring that light of different colors maintains an appropriate intensity ratio when passing through each lens, avoiding some colors being too strong or too weak, and further improving color reproduction.

[0037] In one embodiment of this utility model, the diameter D1 of the first lens 1 satisfies: D1≤30mm. Thus, a smaller diameter of the first lens 1 helps reduce the incident angle of edge rays, thereby reducing aberrations and preventing the lens aperture from being too large, thus meeting the installation space requirements of the final product.

[0038] In one embodiment of this utility model, the light-emitting chip 12 has a light-emitting surface close to the eighth lens 8, and the diameter IC of the light-emitting surface satisfies: IC≤13.5mm. This configuration can more effectively guide light into the lens group, reduce light scattering and loss during transmission, thereby improving the light utilization rate of the entire system, making the projected image brighter, and the smaller diameter of the light-emitting surface results in less heat generation and better thermal stability during operation.

[0039] In one embodiment of this utility model, the effective focal length of the projection optical lens 100 is EFL, the light-emitting chip 12 has a light-emitting surface close to the eighth lens 8, and the distance TTL between the object-side vertex of the first lens 1 and the light-emitting surface satisfies: TTL / EFL ≤ 9. This helps to control the propagation angle and path of light, enabling the light to be focused more accurately on the imaging plane, reducing aberrations, chromatic aberrations, and other problems, thereby improving the clarity and resolution of the image, making the details of the projected image richer and the edges sharper. Furthermore, the compact structure allows for more space for other components, facilitating the layout and design of the entire projection system, and improving the system's integration and stability.

[0040] In one embodiment of this utility model, both the first lens 1 and the second lens 2 are even-order aspherical lenses. This configuration allows even-order aspherical lenses to possess good axial symmetry, making it easier to grasp and calculate the laws governing light refraction and reflection in projection system design. Furthermore, it significantly improves the correction of common aberrations such as spherical aberration, coma, and astigmatism, thereby further enhancing image quality.

[0041] In one embodiment of this invention, the fifth lens 5, the sixth lens 6, and the seventh lens 7 form a bonded lens group. Thus, by forming a bonded lens group, chromatic aberration of the lens is better corrected, the lens's resolving power is improved, and the overall structure of the projection system is simplified, making the projection system more compact and reducing its size and weight.

[0042] In one embodiment of this utility model, a prism 11 is disposed between the light-emitting chip 12 and the ninth lens 9. Thus, the refraction and reflection of light by the prism 11 can help correct aberrations. Simultaneously, the prism 11 also acts as a physical barrier, preventing dust, moisture, and other contaminants from directly contacting the light-emitting chip 12, thus avoiding performance degradation and extending its lifespan. The design of the prism 11 makes the light more concentrated during transmission, further optimizing the optical path and improving the uniformity and stability of the projection effect.

[0043] This utility model also proposes a projection optical system using the projection optical lens 100 as described above; the specific structure of the projection optical lens 100 is as described in the above embodiments. Since the projection optical system adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be described in detail here.

[0044] In one embodiment of this utility model, the focal length of the projection optical lens 100 is f = 10.53, the aperture value is F = 2.0, the luminous surface diameter is IC = 13.5mm, and the material, thickness, radius of curvature, and semi-diameter of each lens are shown in Table 1.

[0045] Table 1 Lens Parameters

[0046]

[0047]

[0048] The design values ​​for the aspherical coefficient in projection optical lenses are shown in Table 2:

[0049] Table 2 Design parameters for aspheric coefficient

[0050] Face number 1 2 3 4 K -0.74633438 -1.42215689 -1.15145988 -0.30162096 4th order term -0.00032934 0.00012940 0.00045161 0.00046437 6th order term 2.718572E-07 -4.839315E-06 -5.786043E-06 -3.909986E-06 8th order term 3.473969E-08 1.322422E-07 6.213612E-08 3.793542E-08 10th-order term -5.166779E-10 -9.394327E-10 -4.141408E-10 -2.394987E-10 12th order term 3.761768E-12 -1.315482E-11 9.996737E-14 1.459434E-13 14th order term -1.417832E-14 2.906119E-13 2.411729E-14 5.952906E-15 16th order term 2.183878E-17 -1.431316E-15 -1.421641E-16 -1.355930E-17

[0051] Figure 2 This is a schematic diagram of the vertical axis color difference curve in this embodiment. Figure 2 As can be seen, the lateral offset of the focal position will not exceed ±2μm. The example can effectively correct color difference and reduce the occurrence of colored edges.

[0052] Figure 3 This is a schematic diagram of the SPOT point in this embodiment. Figure 3 The study demonstrated the focal point distribution of light at different wavelengths, further verifying the lens's high-precision imaging performance and ensuring clear, distortion-free images.

[0053] Figure 4 This is a schematic diagram of the MTF in this embodiment. Figure 3 As can be seen, the MTF of this embodiment is greater than 0.5, which can maintain the contrast of details very well and has excellent imaging performance.

[0054] The above description is merely an exemplary embodiment of the present utility model and does not limit the patent scope of the present utility model. Any equivalent structural transformations made based on the technical concept of the present utility model and the contents of the present utility model specification and drawings, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present utility model.

Claims

1. A projection optical lens, characterized in that, The projection optical lens has an image side and an object side arranged opposite to each other along the optical axis. The projection optical lens includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, an eighth lens, a ninth lens, and a light-emitting chip arranged sequentially along the optical axis from the object side to the image side. The first lens has a negative optical power, the second lens has a negative optical power, the third lens has a positive optical power, the fourth lens has a positive optical power, the fifth lens has a negative optical power, the sixth lens has a positive optical power, the seventh lens has a negative optical power, the eighth lens has a positive optical power, and the ninth lens has a positive optical power. Wherein, the first lens and the second lens are plastic aspherical lenses, the third lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens, the eighth lens and the ninth lens are glass spherical lenses, and the aperture value of the projection optical lens is F≤2.

0.

2. The projection optical lens as described in claim 1, characterized in that, The object plane side of the first lens is convex, and the image plane side is concave. The focal length of the first lens is f1, which satisfies: -30mm. <f1<-15mm; The object plane of the second lens is concave, and the image plane is convex. The focal length of the second lens is f2, which satisfies: -50mm. <f2<-30mm; The object plane side of the third lens is concave, and the image plane side is convex. The focal length of the third lens is f3, which satisfies: 100mm. <f3<200mm; The fourth lens has a convex object plane and a convex image plane. The focal length of the fourth lens is f4, which satisfies the condition: 20mm. <f4<35mm; The fifth lens has a convex surface on the object plane and a concave surface on the image plane. The focal length of the fifth lens is f5, which satisfies -25mm. <f5<-10mm; The object plane side of the sixth lens is convex, and the image plane side is also convex. The focal length of the sixth lens is f6, which satisfies the following condition: 10mm. <f6<20mm; The object plane of the seventh lens is concave, and the image plane is convex. The focal length of the seventh lens is f7, which satisfies: -25mm. <f7<-10mm; The object plane side of the eighth lens is convex, and the image plane side is also convex. The focal length of the eighth lens is f8, which satisfies: 25mm. <f8<40mm; The object plane side of the ninth lens is convex, and the image plane side is also convex. The focal length of the ninth lens is f9, which satisfies: 25mm. <f9<40mm。 3. The projection optical lens as described in claim 1, characterized in that, The refractive index n1 and dispersion coefficient v1 of the first lens satisfy: 1.50≤n1≤1.60; 50.0≤v1≤60.0; The refractive index n2 and dispersion coefficient v2 of the second lens satisfy: 1.50≤n2≤1.60; 50.0≤v2≤60.0; The refractive index n3 and dispersion coefficient v3 of the third lens satisfy: 1.45≤n3≤1.55; 65.0≤v3≤95.0; The refractive index n4 and dispersion coefficient v4 of the fourth lens satisfy: 1.75≤n4≤1.95; 30.0≤v4≤55.0; The refractive index n5 and dispersion coefficient v5 of the fifth lens satisfy: 1.75≤n5≤1.95; 20.0≤v5≤35.0; The refractive index n6 and dispersion coefficient v6 of the sixth lens satisfy: 1.45≤n6≤1.60; 75.0≤v6≤95.0; The refractive index n7 and dispersion coefficient v7 of the seventh lens satisfy: 1.75≤n7≤1.95; 20.0≤v7≤35.0; The refractive index n8 and dispersion coefficient v8 of the eighth lens satisfy: 1.40≤n8≤1.60; 75.0≤v8≤95.0; The refractive index n9 and dispersion coefficient v9 of the ninth lens satisfy the following conditions: 1.75≤n9≤1.95; 20.0≤v9≤35.

0.

4. The projection optical lens as described in claim 1, characterized in that, The diameter D1 of the first lens satisfies: D1≤30mm.

5. The projection optical lens as described in claim 1, characterized in that, The light-emitting chip has a light-emitting surface close to the ninth lens, and the diameter IC of the light-emitting surface satisfies: IC≤13.5mm.

6. The projection optical lens as described in claim 1, characterized in that, The effective focal length of the projection optical lens is EFL, the light-emitting chip has a light-emitting surface close to the ninth lens, and the distance TTL between the object-side vertex of the first lens and the light-emitting surface satisfies: TTL / EFL≤9.

7. The projection optical lens as described in claim 1, characterized in that, Both the first lens and the second lens are even-order aspherical lenses.

8. The projection optical lens as described in claim 1, characterized in that, An aperture stop is provided between the fourth lens and the fifth lens.

9. The projection optical lens as described in claim 1, characterized in that, The fifth lens, the sixth lens, and the seventh lens form an adhesive lens group.

10. A projection optical system, characterized in that, Use the projection optical lens as described in any one of claims 1-9.

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