Wide-angle projection lens and system thereof

Abstract

The application discloses a wide-angle projection lens and a system thereof. The wide-angle projection lens comprises, in sequence along the optical axis direction, a refractive assembly and a reflection assembly. The refractive assembly comprises a fixed group and a double-group linkage focusing group. The fixed group comprises a first aspheric lens, a first spherical lens, a double-cemented negative focal length lens, a double-cemented positive focal length lens, a negative focal length lens, a diaphragm and a positive focal length lens. The double-cemented negative focal length lens is composed of a second spherical lens and a third spherical lens. The double-cemented positive focal length lens is composed of a fourth spherical lens and a fifth spherical lens. The negative focal length lens is a sixth spherical lens. The positive focal length lens is a seventh spherical lens. The double-group linkage focusing group comprises a double-cemented lens, a tenth spherical lens and a second aspheric lens. The double-cemented lens is composed of an eighth spherical lens and a ninth spherical lens. The reflection assembly comprises an aspheric mirror. The embodiment of the application can realize super-short-focus clear projection and can be widely applied to the field of optical technology.

Description

Technical Field

[0001] This invention relates to the field of optical technology, and more particularly to a wide-angle projection lens and system thereof. Background Technology

[0002] Projection lenses are widely used in education, entertainment, and other fields. In certain applications, ultra-short-throw projection is required even with a small projection distance. Lenses with a throw ratio of 0.3 or less can project images exceeding 100 inches in size even at very close distances to the screen; this is also known as ultra-short-throw projection. Achieving ultra-short-throw projection presents significant challenges. For example, changes in projection distance can cause drastic changes in image parameters, leading to blurred image focus. Summary of the Invention

[0003] In view of this, the purpose of this invention is to provide a wide-angle projection lens and system that can achieve clear projection with ultra-short throw.

[0004] In a first aspect, embodiments of the present invention provide a wide-angle projection lens, comprising a refractive assembly and a reflective assembly sequentially along the optical axis. The refractive assembly includes a fixed group and a dual-group linkage focusing group. The fixed group includes a first aspherical lens, a first spherical lens, a cemented doublet negative focal length lens, a cemented doublet positive focal length lens, a negative focal length lens, an aperture stop, and a positive focal length lens. The cemented doublet negative focal length lens is composed of a second spherical lens and a third spherical lens. The cemented doublet positive focal length lens is composed of a fourth spherical lens and a fifth spherical lens. The negative focal length lens is a sixth spherical lens, and the positive focal length lens is a seventh spherical lens. The dual-group linkage focusing group includes a cemented doublet lens, a tenth spherical lens, and a second aspherical lens. The cemented doublet lens is composed of an eighth spherical lens and a ninth spherical lens. The reflective assembly includes an aspherical reflector.

[0005] Optionally, the refractive index and dispersion coefficient of the second spherical lens satisfy the following relationship:

[0006] 1.85≤n d2 ≤2.15

[0007] 15≤v d2 ≤35

[0008] Where, n d2 V represents the refractive index of the second spherical lens. d2 This represents the dispersion coefficient of the second spherical lens.

[0009] Optionally, the refractive index and dispersion coefficient of the third spherical lens satisfy the following relationship:

[0010] 1.45≤n d3 ≤1.65

[0011] 50≤v d3 ≤80

[0012] Where, n d3 The refractive index of the third spherical lens, v d3 This represents the dispersion coefficient of the third spherical lens.

[0013] Optionally, the refractive index and dispersion coefficient of the eighth spherical lens satisfy the following relationship:

[0014] 1.8≤n d8 ≤2.2

[0015] 13≤v d8 ≤37

[0016] Where, n d8 The refractive index of the eighth spherical lens, v d8 This represents the dispersion coefficient of the eighth spherical lens.

[0017] Optionally, the refractive index and dispersion coefficient of the ninth spherical lens satisfy the following relationship:

[0018] 1.4≤n d9 ≤1.7

[0019] 49≤v d9 ≤81

[0020] Where, n d9 The refractive index of the ninth spherical lens, v d9 This represents the dispersion coefficient of the ninth spherical lens.

[0021] Optionally, the refractive index of the fourth spherical lens is less than that of the fifth spherical lens, and the Abbe number of the fourth spherical lens is greater than that of the fifth spherical lens.

[0022] Optionally, the first aspherical lens is a biconvex aspherical lens, the first spherical lens is a biconvex spherical lens, the second spherical lens is a biconcave spherical lens, the third spherical lens is a plano-convex spherical lens, the fourth spherical lens is a crescent-shaped aspherical lens, the fifth spherical lens is a biconvex spherical lens, the sixth spherical lens is a biconcave spherical lens, the seventh and eighth spherical lenses are both biconvex spherical lenses, the ninth and tenth spherical lenses are both biconcave spherical lenses, and the second aspherical lens is a crescent-shaped aspherical lens.

[0023] Optionally, the focal length of the wide-angle projection lens satisfies the following relationship:

[0024] -6≤f1 / EFL≤-5

[0025] -6≤f2 / EFL≤-5

[0026] 20≤fasp / EFL≤150

[0027] Where f1 represents the focal length of the refractive component, f2 represents the focal length of the reflective component, EFL represents the focal length of the wide-angle projection lens, and fasp represents the focal length of the second aspherical lens.

[0028] Secondly, embodiments of the present invention provide a wide-angle projection system, which includes, in sequence along the optical axis, an illumination component and the aforementioned wide-angle projection lens, wherein the illumination component includes an image chip surface and protective glass, an equivalent length prism, and an optical engine protective glass.

[0029] Optionally, the total length of the wide-angle projection lens satisfies the following relationship:

[0030] 0.08≤BFL / TOL≤0.15

[0031] 0.3≤D / TOL≤0.5

[0032] Where TOL represents the total length of the wide-angle projection lens, BFL represents the equivalent length of the air plate between the image chip surface and the first aspherical lens, and D represents the distance between the vertex of the second aspherical lens and the vertex of the aspherical mirror.

[0033] The implementation of this invention provides the following beneficial effects: The wide-angle projection lens in this embodiment includes a refraction component and a reflection component along the optical axis. The refraction component includes a fixed group and a dual-group linkage focusing group. The fixed group includes an aspherical lens and several spherical lenses. The dual-group linkage focusing group includes several spherical lenses. The incident light passes through the refraction component to balance distortion, coma, spherical aberration, field curvature, and astigmatism, and is corrected by the aspherical reflector before being projected onto a plane at a preset distance to form a high-definition image, thereby achieving clear projection in ultra-short throw. Attached Figure Description

[0034] Figure 1 This is a schematic diagram of the structure of a wide-angle projection lens provided in an embodiment of the present invention;

[0035] Figure 2 This is a schematic diagram of the structure of a wide-angle projection system provided in an embodiment of the present invention;

[0036] Figure 3 This is an optical path diagram of a wide-angle projection system provided in an embodiment of the present invention;

[0037] Figure 4 This is a lens distribution diagram of a wide-angle projection system provided in an embodiment of the present invention;

[0038] Figure 5This is a projection optical path diagram of a wide-angle projection system provided in an embodiment of the present invention;

[0039] Figure 6 This is a calibration comparison diagram of a wide-angle projection system provided in an embodiment of the present invention;

[0040] Figure 7 This is a projection area distribution diagram of a wide-angle projection system provided in an embodiment of the present invention;

[0041] Figure 8 This is a movement curve diagram of a dual-group linkage focusing group provided in an embodiment of the present invention;

[0042] Figure 9 This is an optical transfer function curve of a wide-angle projection system on a 75-inch projection screen provided in an embodiment of the present invention;

[0043] Figure 10 This is an optical transfer function curve of a wide-angle projection system on a 100-inch projection screen provided in an embodiment of the present invention;

[0044] Figure 11 This is an optical transfer function curve of a wide-angle projection system provided in an embodiment of the present invention on a 140-inch projection screen. Detailed Implementation

[0045] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments. The step numbers in the following embodiments are only for ease of explanation and do not limit the order of the steps. The execution order of each step in the embodiments can be adapted according to the understanding of those skilled in the art.

[0046] In the following description, references are made to “some embodiments,” which describe a subset of all possible embodiments. However, it is understood that “some embodiments” may be the same subset or different subsets of all possible embodiments and may be combined with each other without conflict.

[0047] In the following description, the terms "first, second, third" are used merely to distinguish similar objects and do not represent a specific ordering of objects. It is understood that "first, second, third" may be interchanged in a specific order or sequence where permitted, so that the embodiments of the invention described herein can be implemented in an order other than that illustrated or described herein.

[0048] Unless otherwise defined, all technical and scientific terms used in the embodiments of this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used in the embodiments of this invention is for descriptive purposes only and is not intended to limit the invention.

[0049] Before providing a further detailed description of the embodiments of the present invention, the nouns and terms involved in the embodiments of the present invention will be explained, and the nouns and terms involved in the embodiments of the present invention shall be interpreted as follows.

[0050] See Figure 1 This invention provides a wide-angle projection lens, which includes a refractive assembly 105 and a reflective assembly 106 sequentially along the optical axis. The refractive assembly 105 includes a fixed group 110 and a dual-group linkage focusing group 120. The fixed group 110 includes a first aspherical lens 111, a first spherical lens 112, a cemented doublet negative focal length lens, a cemented doublet positive focal length lens, a negative focal length lens 117, an aperture stop 118, and a positive focal length lens 119. The cemented doublet negative focal length lens is composed of a second spherical lens 113 and... The third spherical lens 114 is composed of a cemented doublet positive focal length lens, which is composed of a fourth spherical lens 115 and a fifth spherical lens 116. The negative focal length lens is a sixth spherical lens 117, and the positive focal length lens is a seventh spherical lens 119. The dual-group linkage focusing group includes a cemented doublet lens, a tenth spherical lens 123, and a second aspherical lens 124. The cemented doublet lens is composed of an eighth spherical lens 121 and a ninth spherical lens 122. The reflecting assembly includes an aspherical mirror 130.

[0051] The first focusing group (focus1) is composed of the eighth spherical lens 121 and the ninth spherical lens 122, while the second focusing group (focus2) is composed of the tenth spherical lens 123 and the second aspherical lens 124. The combined focal length of the second focusing group (focus2) is positive. The first focusing group (focus1) and the second focusing group (focus2) together form a dual-group linkage focusing group 120. The fixed group 110 remains fixed along the optical axis, while the dual-group linkage focusing group 120 can move along the optical axis.

[0052] See Figure 3The incident light passes through the first aspherical lens 111 to correct and balance field curvature and coma in the wide-angle projection lens; then through the first spherical lens 112 to correct and balance distortion and astigmatism in the wide-angle projection lens, as well as correct some field curvature and coma; then through a cemented doublet negative focal length lens composed of the second spherical lens 113 and the third spherical lens 114 to correct axial chromatic aberration and introduce some negative spherical aberration to balance the overall spherical aberration; then through a cemented doublet positive focal length lens composed of the fourth spherical lens 115 and the fifth spherical lens 116 to balance coma and astigmatism at various wavelengths off-axis; then through the sixth spherical lens 117 to increase the lens F-number, expand the maximum divergence angle of the acceptable beam, improve overall illumination, and balance some system spherical aberration and astigmatism; finally, through the aperture stop 118 to block stray light exceeding the aperture specifications, wherein the light... The aperture 118 determines the entrance pupil diameter of the lens; then, the seventh spherical lens 119 is appropriately bent to reduce the diameter of subsequent lens groups, so that the distance between the beams in the off-axis fields of view is increased after a certain distance, becoming more dispersed (the magnification of the refractive assembly 110 mainly depends on this); then, a cemented doublet composed of the eighth spherical lens 121 and the ninth spherical lens 122 balances a certain degree of variation in transverse chromatic aberration and some distortion within the focusing range; then, focus2 composed of the tenth spherical lens 123 and the second aspherical lens 124 balances the variation in distortion, coma, field curvature, and astigmatism within the focusing range; finally, the light passes through the aspherical mirror 130, which corrects the final coma, astigmatism, spherical aberration, and distortion in the system, and reflects the light onto a plane at a certain projection distance to form a high-definition image. IMA1 represents the primary imaging plane.

[0053] It should be noted that, as needed, a steering prism, a reflector, etc., can be added to the air gap between the reflector 130 and the refractive assembly 105 so that the concave surface of the reflector does not face the refractive assembly. Therefore, this addable part and the reflector are collectively referred to as the reflector assembly 106.

[0054] Optionally, the refractive index and dispersion coefficient of the second spherical lens satisfy the following relationship:

[0055] 1.85≤n d2 ≤2.15

[0056] 15≤v d2 ≤35

[0057] Where, n d2 V represents the refractive index of the second spherical lens. d2 This represents the dispersion coefficient of the second spherical lens.

[0058] It should be noted that the second spherical lens is a high refractive index and high dispersion lens. The refractive index and dispersion of the second spherical lens are determined according to the actual application, and this embodiment does not impose specific limitations.

[0059] Optionally, the refractive index and dispersion coefficient of the third spherical lens satisfy the following relationship:

[0060] 1.45≤n d3 ≤1.65

[0061] 50≤v d3 ≤80

[0062] Where, n d3 The refractive index of the third spherical lens, v d3 This represents the dispersion coefficient of the third spherical lens.

[0063] It should be noted that the third spherical lens is a low-refractive-index, low-dispersion lens. The refractive index and dispersion of the third spherical lens are determined based on the actual application, and this embodiment does not impose specific limitations. The refractive indices and dispersions of the second and third spherical lenses are used in combination according to actual conditions.

[0064] Optionally, the refractive index and dispersion coefficient of the eighth spherical lens satisfy the following relationship:

[0065] 1.8≤n d8 ≤2.2

[0066] 13≤v d8 ≤37

[0067] Where, n d8 The refractive index of the eighth spherical lens, v d8 This represents the dispersion coefficient of the eighth spherical lens.

[0068] The eighth spherical lens is a high refractive index and high dispersion lens. The refractive index and dispersion of the eighth spherical lens are determined according to the actual application, and this embodiment does not impose specific limitations.

[0069] Optionally, the refractive index and dispersion coefficient of the ninth spherical lens satisfy the following relationship:

[0070] 1.4≤n d9 ≤1.7

[0071] 49≤v d9 ≤81

[0072] Where, n d9 The refractive index of the ninth spherical lens, v d9 This represents the dispersion coefficient of the ninth spherical lens.

[0073] The ninth spherical lens is a low-refractive-index, low-dispersion lens. The refractive index and dispersion of the ninth spherical lens are determined based on the actual application; this embodiment does not impose specific limitations. The refractive indices and dispersions of the eighth and ninth spherical lenses are used in combination according to actual conditions.

[0074] Optionally, the refractive index of the fourth spherical lens is less than that of the fifth spherical lens, and the Abbe number of the fourth spherical lens is greater than that of the fifth spherical lens.

[0075] Both the fourth and fifth spherical lenses are high-refractive-index, high-dispersion lenses. The refractive index and Abbe number of the fourth and fifth spherical lenses are determined according to the actual application, and no specific limitations are imposed in this embodiment.

[0076] Optionally, the first aspherical lens is a biconvex aspherical lens, the first spherical lens is a biconvex spherical lens, the second spherical lens is a biconcave spherical lens, the third spherical lens is a plano-convex spherical lens, the fourth spherical lens is a crescent-shaped aspherical lens, the fifth spherical lens is a biconvex spherical lens, the sixth spherical lens is a biconcave spherical lens, the seventh and eighth spherical lenses are both biconvex spherical lenses, the ninth and tenth spherical lenses are both biconcave spherical lenses, and the second aspherical lens is a crescent-shaped aspherical lens.

[0077] The first aspherical lens, the first spherical lens, the third spherical lens, the fifth spherical lens, the seventh spherical lens, the eighth spherical lens, and the second aspherical lens have positive focal lengths, while the second spherical lens, the fourth spherical lens, the sixth spherical lens, the ninth spherical lens, and the tenth spherical lens have negative focal lengths. The concave portion of the fourth spherical lens faces the reflecting component, the concave portion of the second aspherical lens faces the reflecting component, and the concave portion of the concave aspherical mirror faces the reflecting component.

[0078] It should be noted that the first aspherical lens and the first to tenth spherical lenses can be made of glass, while the second aspherical lens can be made of plastic.

[0079] Optionally, the focal length of the wide-angle projection lens satisfies the following relationship:

[0080] -6≤f1 / EFL≤-5

[0081] -6≤f2 / EFL≤-5

[0082] 20≤fasp / EFL≤150

[0083] Where f1 represents the focal length of the refractive component, f2 represents the focal length of the reflective component, EFL represents the focal length of the wide-angle projection lens, and fasp represents the focal length of the second aspherical lens.

[0084] The focal lengths of the wide-angle projection lens, the refractive component, the reflective component, and the second aspherical lens are used in combination, and the specific combination is determined according to the actual application. This embodiment does not impose any specific limitations.

[0085] See Figure 2This invention provides a wide-angle projection system, which includes, in sequence along the optical axis 102, an illumination component and the aforementioned wide-angle projection lens. The illumination component includes an image chip surface and protective glass 101, an equivalent length prism 103, and an optical engine protective glass 104.

[0086] See Figure 3 Light passes through the image chip surface and protective glass 101 via transmission or reflection, and is modulated by the chip to form the desired image. It then passes through a prism 103 of equivalent length (this prism may actually be a multicolor combining prism or a steering prism, etc.), through the optical engine protective glass 104, and enters the refraction component 105. The light emitted by the illumination component is a telecentric optical path.

[0087] Optionally, see Figure 4 The total length of the wide-angle projection lens satisfies the following relationship:

[0088] 0.08≤BFL / TOL≤0.15

[0089] 0.3≤D / TOL≤0.5

[0090] Where TOL represents the total length of the wide-angle projection lens, BFL represents the equivalent length of the air plate between the image chip surface and the first aspherical lens, and D represents the distance between the vertex of the second aspherical lens and the vertex of the aspherical mirror.

[0091] It should be noted that the total length of the wide-angle projection lens, the equivalent air plate length between the image chip surface and the first aspherical lens, and the distance between the second aspherical lens and the aspherical reflector are determined according to the actual application, and this embodiment does not impose specific limitations.

[0092] Figure 5 This is a ray diagram representing a wide-angle projection system, where M represents the wide-angle projection system, R represents the ray, and L represents the projected image. Figure 6 A comparison chart showing optical distortion correction of wide-angle projection systems; Figure 7 This indicates the imaging range area of ​​a wide-angle projection system. (Combined with...) Figures 5 to 7 The characteristics of a catadioptric lens: large angles introduce huge optical distortion, and large angles also cause the image center O' to deviate significantly from the optical axis center O, by 140% of half the image height. The actual imaging range of the lens is the annular area enclosed by radii Rmax and Rmin. Since the chip is rectangular, the frame represents the actual projected imaging area. Optical distortion calculations typically use paraxial magnification of the optical axis as a reference. Figure 6(The uncorrected curve in the image) Due to the image shift characteristics of catadioptric lenses, the paraxial magnification at its optical axis point O is no longer a reference point. Therefore, point O', where the shortest distance Rmin between the image edge and optical axis point O is the minimum magnification reference point, is used. The calculation and optimization are then performed to obtain... Figure 6 The optical distortion (after correction) represented by the mid-solid curve. For example... Figure 7 As shown, the actual projection imaging area has excellent grid distortion (the short black lines extending from each point are the orthogonal components of the distortion at that point in the x / y direction), while the optical axis has a large distortion but does not actually participate in the imaging, thus achieving extremely low image distortion.

[0093] See Figure 8 , Figure 8 This graph shows the movement curves of the first focusing group (focus1) and the second focusing group (focus2) in the dual-group linkage focusing system. Figure 8 It can be seen that the first focusing group (focus1) and the second focusing group (focus2) are moving curves with the same direction but different curvatures.

[0094] The implementation of this invention provides the following beneficial effects: The wide-angle projection lens in this embodiment includes a refraction component and a reflection component along the optical axis. The refraction component includes a fixed group and a dual-group linkage focusing group. The fixed group includes an aspherical lens and several spherical lenses. The first focusing group includes several spherical lenses, and the second focusing group includes an aspherical lens and several spherical lenses. The incident light passes through the refraction component to balance distortion, coma, spherical aberration, field curvature, and astigmatism, and is then corrected by the aspherical reflector before being projected onto a plane at a preset distance to form a high-definition image, thereby achieving clear projection in ultra-short throw mode.

[0095] In addition, this embodiment includes two aspherical lenses and several spherical lenses, which can reduce system errors and achieve clear focusing over a wide range from 75 inches to 140 inches with a projection ratio of 0.21; see also... Figure 5 (b) Throw ratio = Screen width (N) / Throw distance (P), where H represents screen height. Without architectural changes, the throw ratio can be adjusted within the range of 0.19-0.26. For details, see [link to relevant documentation]. Figures 9-11 , Figure 9 A graph representing the modulation transfer function of a 75-foot projected image. Figure 10 The modulation transfer function curve represents the projection image at a height of 100 feet. Figure 11 The graph represents the modulation transfer function (MTF) curves of a 140-foot projected image, where T and S represent the optical transfer function curves in the tangential and radial directions, respectively. From... Figures 9-11As can be seen, the simulation results are within the standard range, meaning that the wide-angle projection system of this embodiment can have good imaging quality.

[0096] In a specific embodiment, the parameter design of each lens in the wide-angle projection system is shown in Table 1 and Table 2. Table 1 includes the lens parameters of lenses 101 to 104 in the illumination assembly and the lens parameters of lenses 111 to 130 in the wide-angle projection lens. Table 2 includes the relevant parameters of the first aspherical lens 111, the second aspherical lens 124 and the aspherical reflector 130.

[0097] Table 1

[0098]

[0099] Table 2

[0100]

[0101] The above is a detailed description of the preferred embodiments of the present invention. However, the present invention is not limited to the embodiments described. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of the present invention. All such equivalent modifications or substitutions are included within the scope defined by the claims of this application.

Claims

1. A wide-angle projection lens, characterized in that, The system includes a refractive assembly and a reflective assembly sequentially along the optical axis. The refractive assembly comprises a fixed group and a dual-group linkage focusing group. The fixed group includes a first aspherical lens, a first spherical lens, a cemented doublet negative focal length lens, a cemented doublet positive focal length lens, a negative focal length lens, an aperture stop, and a positive focal length lens. The cemented doublet negative focal length lens is composed of a second and a third spherical lens, the cemented doublet positive focal length lens is composed of a fourth and a fifth spherical lens, the negative focal length lens is a sixth spherical lens, and the positive focal length lens is a seventh spherical lens. The dual-group linkage focusing group includes a cemented doublet lens, a tenth spherical lens, and a second aspherical lens. The cemented doublet lens is composed of an eighth and a ninth spherical lens. The reflective assembly includes an aspherical mirror. The first aspherical lens is a biconvex aspherical lens, and the first spherical lens... The first aspherical lens is a biconvex spherical lens, the second spherical lens is a biconcave spherical lens, the third spherical lens is a plano-convex spherical lens, the fourth spherical lens is a crescent-shaped spherical lens, the fifth spherical lens is a biconvex spherical lens, the sixth spherical lens is a biconcave spherical lens, the seventh and eighth spherical lenses are both biconvex spherical lenses, the ninth and tenth spherical lenses are both biconcave spherical lenses, and the second aspherical lens is a crescent-shaped aspherical lens; the focal lengths of the first aspherical lens, the first spherical lens, the third spherical lens, the fifth spherical lens, the seventh spherical lens, the eighth spherical lens, and the second aspherical lens are positive, while the focal lengths of the second spherical lens, the fourth spherical lens, the sixth spherical lens, the ninth spherical lens, and the tenth spherical lens are negative.

2. The wide-angle projection lens according to claim 1, characterized in that, The refractive index and dispersion coefficient of the second spherical lens satisfy the following relationship: 1.85≤n d2 ≤2.15 15≤v d2 ≤35 Where, n d2 V represents the refractive index of the second spherical lens. d2 This represents the dispersion coefficient of the second spherical lens.

3. The wide-angle projection lens according to claim 2, characterized in that, The refractive index and dispersion coefficient of the third spherical lens satisfy the following relationship: 1.45≤n d3 ≤1.65 50≤v d3 ≤80 Where, n d3 The refractive index of the third spherical lens, v d3 This represents the dispersion coefficient of the third spherical lens.

4. The wide-angle projection lens according to claim 1, characterized in that, The refractive index and dispersion coefficient of the eighth spherical lens satisfy the following relationship: 1.8≤n d8 ≤2.2 13≤v d8 ≤37 Where, n d8 The refractive index of the eighth spherical lens, v d8 This represents the dispersion coefficient of the eighth spherical lens.

5. The wide-angle projection lens according to claim 4, characterized in that, The refractive index and dispersion coefficient of the ninth spherical lens satisfy the following relationship: 1.4≤n d9 ≤1.7 49≤v d9 ≤81 Where, n d9 The refractive index of the ninth spherical lens, v d9 This represents the dispersion coefficient of the ninth spherical lens.

6. The wide-angle projection lens according to claim 1, characterized in that, The refractive index of the fourth spherical lens is less than that of the fifth spherical lens, and the Abbe number of the fourth spherical lens is greater than that of the fifth spherical lens.

7. The wide-angle projection lens according to any one of claims 1-6, characterized in that, The first aspherical lens is a biconvex aspherical lens, the first spherical lens is a biconvex spherical lens, the second spherical lens is a biconcave spherical lens, the third spherical lens is a plano-convex spherical lens, the fourth spherical lens is a crescent-shaped aspherical lens, the fifth spherical lens is a biconvex spherical lens, the sixth spherical lens is a biconcave spherical lens, the seventh and eighth spherical lenses are both biconvex spherical lenses, the ninth and tenth spherical lenses are both biconcave spherical lenses, and the second aspherical lens is a crescent-shaped aspherical lens.

8. The wide-angle projection lens according to any one of claims 1-6, characterized in that, The focal length of a wide-angle projection lens satisfies the following relationship: -6≤f1 / EFL≤-5 -6≤f2 / EFL≤-5 20≤fasp / EFL≤150 Where f1 represents the focal length of the refractive component, f2 represents the focal length of the reflective component, EFL represents the focal length of the wide-angle projection lens, and fasp represents the focal length of the second aspherical lens.

9. A wide-angle projection system, characterized in that, Along the optical axis, it sequentially includes: an illumination assembly and a wide-angle projection lens as described in any one of claims 1-8, wherein the illumination assembly includes an image chip surface and protective glass, an equivalent length prism, and an optical engine protective glass.

10. The wide-angle projection system according to claim 9, characterized in that, The total length of the wide-angle projection lens satisfies the following relationship: 0.08≤BFL / TOL≤0.15 0.3≤D / TOL≤0.5 Where TOL represents the total length of the wide-angle projection lens, BFL represents the equivalent length of the air plate between the image chip surface and the first aspherical lens, and D represents the distance between the vertex of the second aspherical lens and the vertex of the aspherical mirror.

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