Wide-angle zoom projection lens

Abstract

This invention relates to a wide-angle zoom projection lens, comprising, from the magnification side to the reduction side, a first lens group with negative refractive power, a second lens group, a third lens group with positive refractive power, a fourth lens group with positive refractive power, a fifth lens group with positive refractive power, and a sixth lens group with positive refractive power. The lens also includes an aperture. During zooming, the first and sixth lens groups are fixed, while the second to fifth lens groups move along the optical axis to achieve a change in focal length. The foremost lens in the first lens group, closest to the magnification side, is a negative refractive power aspherical lens to achieve a wide-angle effect. The reduction side of the lens has a telecentric characteristic. This provides a wide-angle zoom projection lens that simultaneously satisfies the requirements of high brightness, wide angle, and zoom projection while achieving high resolution.

Description

Wide-angle zoom projection lens This invention relates to a wide-angle zoom projection lens, and more particularly to a lens that simultaneously meets the projection requirements of high brightness, wide angle and zoom while achieving high resolution. Wide-angle projectors require less projection distance and can project a large image from a short distance, making them easy to install. They only need to be placed in front of the projection screen, giving them an advantage in terms of space saving and ease of installation compared to conventional projectors. Furthermore, in addition to meeting the aforementioned wide-angle projection requirements, projection lenses usually need to zoom through multiple lens groups to adjust the projected image to an appropriate size, depending on the projector's installation position. Therefore, enabling a projection lens to simultaneously meet the projection requirements of both wide-angle and zoom while also maintaining projection image quality is the problem that this invention aims to solve. The main objective of this invention is to provide a wide-angle zoom projection lens that simultaneously meets the requirements of high brightness, wide angle, and zoom projection while achieving high resolution. To achieve the above-mentioned effects, the present invention includes a lens with six lens groups arranged sequentially from the magnification side to the reduction side: a first lens group with negative refractive power, a second lens group, a third lens group with positive refractive power, a fourth lens group with positive refractive power, a fifth lens group with positive refractive power, and a sixth lens group with positive refractive power. The lens also includes an aperture. During zooming, the first and sixth lens groups are fixed, while the second to fifth lens groups move along the optical axis to achieve a change in focal length. The foremost lens in the first lens group, closest to the magnification side, is a negative refractive power aspherical lens to achieve a wide-angle effect. The reduction side of the lens has a telephoto lens. The focal length is defined as follows: 1.3≤Ww / Dw≤2.5, where Ww is the width of the projected image at the wide-angle end and Dw is the projection distance at the wide-angle end; where 1.05≤|ft / fw|≤1.7, 1.2≤|f1 / fw|≤1.7, 4.5≤|f5 / fw|≤35.0, 4.0≤Bf / fw≤5.0, where ft is the focal length of the entire lens at the telephoto end, fw is the focal length of the entire lens at the wide-angle end, f1 is the focal length of the first lens group, f5 is the focal length of the fifth lens group, and Bf is the back focal length converted to air; CA / IHm≤12, where CA is the effective diameter of the foremost lens and IHm is the maximum image height on the reduced side of the lens. Furthermore, the aperture is located between or within the fourth and fifth lens groups, and the F-number of the aperture is between 1.7 and 2.6. Also, the first lens group has at least one glass lens with a refractive index (nd) ≥ 1.75 and at least one glass lens with an Abbe number (vd) ≥ 55, and the fifth lens group has at least one cemented lens, at least one glass lens with a refractive index (nd) ≥ 1.75 and at least one glass lens with an Abbe number (vd) ≥ 60. In addition, the first lens group can be grouped together or split into multiple groups for focusing and image plane curvature adjustment. Furthermore, the present invention includes a lens with five lens groups arranged sequentially from the magnification side to the reduction side: a first lens group with negative refractive power, a second lens group, a third lens group with positive refractive power, a fourth lens group with positive refractive power, and a fifth lens group with positive refractive power. The lens also has an aperture. During zooming, the first and fifth lens groups are fixed, while the second to fourth lens groups move along the optical axis to achieve a change in focal length. The foremost lens in the first lens group, closest to the magnification side, is a negative refractive power aspherical lens to achieve a wide-angle effect. The reduction side of the lens has a telecentric characteristic, and 1 0.3≤Ww / Dw≤2.5, where Ww is the width of the projected image at the wide-angle end, and Dw is the projection distance at the wide-angle end; where 1.05≤|ft / fw|≤1.3, 3≤|f1 / fw|≤5, 4.5≤|f4 / fw|≤50.0, 4.0≤Bf / fw≤5.0, where ft is the focal length of the entire lens at the telephoto end, fw is the focal length of the entire lens at the wide-angle end, f1 is the focal length of the first lens group, f4 is the focal length of the fourth lens group, and Bf is the back focal length converted to air; CA / IHm≤12, where CA is the effective diameter of the foremost lens, and IHm is the maximum image height on the reduced side of the lens. Furthermore, the aperture is located between or within the third and fourth lens groups, and the F-number of the aperture is between 1.7 and 2.6. Also, the first lens group has at least one glass lens with a refractive index (nd) ≥ 1.75 and at least one glass lens with an Abbe number (vd) ≥ 55, and the fourth lens group has at least one cemented lens, at least one glass lens with a refractive index (nd) ≥ 1.75 and at least one glass lens with an Abbe number (vd) ≥ 60. In addition, the first lens group can be grouped together or split into multiple groups for focusing and image plane curvature adjustment. First, please refer to Figures 1A and 1B. The wide-angle zoom projection lens 10 of Embodiment 1 of the present invention comprises, from the magnification side to the reduction side, a first lens group 11 with negative refractive power, a second lens group 12, a third lens group 13 with positive refractive power, a fourth lens group 14 with positive refractive power, a fifth lens group 15 with positive refractive power, and a sixth lens group 16 with positive refractive power, as well as a prism P. The lens is also provided with an aperture S1 between (or within) the fourth and fifth lens groups 14 and 15, and the F-value of the aperture S1 is between 1.8 and 2.0. During zooming, the first lens group 11 and the sixth lens group 16 are fixed, and the second to fifth lens groups 12, 13, 14, and 15 move along the optical axis to achieve a change in focal length. The foremost lens 1L1 of the first lens group 11, closest to the magnification side of the lens, is a negative refractive power aspherical lens used to achieve a wide-angle effect. The reduction side of the lens has a telecentric characteristic. Among them, Ww / Dw=1.980, |ft / fw|=1.396, |f1 / fw|=1.532, |f5 / fw|=20.875, Bf / fw=4.709, CA / IHm=8.819, Ww is the width of the projected image at the wide-angle end, Dw is the projection distance at the wide-angle end, ft is the focal length of the entire lens at the telephoto end, fw is the focal length of the entire lens at the wide-angle end, f1 is the focal length of the first lens group, f5 is the focal length of the fifth lens group, Bf is the back focal length when converted to air, CA is the effective diameter of the foremost lens, and IHm is the maximum image height on the reduction side of the lens. The lens design parameters of the wide-angle zoom projection lens 10 are shown in Tables 1A, 1B, and 1C. Among them, 1L1R1 is the magnifying side surface (R1) of the foremost (first) lens (1L1), 1L1R2 is the reducing side surface (R2) of the first lens (1L1), 1L2R1 is the magnifying side surface (R1) of the second lens (1L2), 1L2R2 is the reducing side surface (R2) of the second lens (1L2), ... 1L18R1 is the magnifying side surface (R1) of the eighteenth lens (1L18), 1L18R2 is the reducing side surface (R2) of the eighteenth lens (1L18), and so on. However, the tenth lens (1L10), the eleventh lens (1L11), and the twelfth lens (1L12) can form a cemented lens, and the fourteenth lens (1L14), the fifteenth lens (1L15), and the sixteenth lens (1L16) can form a cemented lens. Table 1A Table 1B Table 1C The wide-angle zoom projection lens 10 uses a first wavelength of 620nm (λ1), a second wavelength of 550nm (λ2), and a third wavelength of 460nm (λ3) at its wide-angle end, along with relative field heights of 0.00, 0.20, 0.40, 0.60, 0.80, and 1.00, to simulate the ray aberrations diagram shown in Figure 1C. The characteristic curves of meridional aberrations (Y-FAN field aberrations) and sagittal aberrations (X-FAN field aberrations) are then observed. The aberration characteristic curves produce aberration values ​​controlled within the range of (-0.02mm, 0.02mm). The telephoto end of the wide-angle zoom projection lens 10 simulates the ray aberration diagram of Figure 1D with a first wavelength of 620nm (λ1), a second wavelength of 550nm (λ2), and a third wavelength of 460nm (λ3), and with relative image heights of 0.00, 0.20, 0.40, 0.60, 0.80, and 1.00, respectively. The meridional aberration characteristic curves and sagittal aberration characteristic curves are observed, and the aberration values ​​produced are controlled within the range of (-0.03mm, 0.02mm). Next, referring to Figures 2A and 2B, the wide-angle zoom projection lens 20 of Embodiment 2 of the present invention comprises, from the magnification side to the reduction side, a first lens group 21 with negative refractive power, a second lens group 22, a third lens group 23 with positive refractive power, a fourth lens group 24 with positive refractive power, a fifth lens group 25 with positive refractive power, and a sixth lens group 26 with positive refractive power, as well as a prism P. The lens is also provided with an aperture S2 between (or within) the fourth and fifth lens groups 24 and 25, and the F-value of the aperture S2 is between 1.8 and 2.09. During zooming, the first lens group 21 and the sixth lens group 26 are fixed, and the second to fifth lens groups 22, 23, 24, and 25 move along the optical axis to achieve a change in focal length. The foremost lens 2L1 of the first lens group 21, closest to the magnification side of the lens, is a negative refractive power aspherical lens used to achieve a wide-angle effect. The reduction side of the lens has a telecentric characteristic. Among them, Ww / Dw=1.981, |ft / fw|=1.574, |f1 / fw|=1.561, |f5 / fw|=19.683, Bf / fw=4.709, CA / IHm=8.667, Ww is the width of the projected image at the wide-angle end, Dw is the projection distance at the wide-angle end, ft is the focal length of the entire lens at the telephoto end, fw is the focal length of the entire lens at the wide-angle end, f1 is the focal length of the first lens group, f5 is the focal length of the fifth lens group, Bf is the back focal length when converted to air, CA is the effective diameter of the foremost lens, and IHm is the maximum image height on the reduction side of the lens. The lens design parameters of the wide-angle zoom projection lens 20 are shown in Tables 2A, 2B, and 2C. Among them, 2L1R1 is the magnifying side surface (R1) of the foremost (first) lens (2L1), 2L1R2 is the reducing side surface (R2) of the first lens (2L1), 2L2R1 is the magnifying side surface (R1) of the second lens (2L2), 2L2R2 is the reducing side surface (R2) of the second lens (2L2), ... 2L18R1 is the magnifying side surface (R1) of the eighteenth lens (2L18), 2L18R2 is the reducing side surface (R2) of the eighteenth lens (2L18), and so on. However, the tenth lens (2L10), the eleventh lens (2L11), and the twelfth lens (2L12) can form a cemented lens, and the fourteenth lens (2L14), the fifteenth lens (2L15), and the sixteenth lens (2L16) can form a cemented lens. Table 2A Table 2B Table 2C The wide-angle zoom projection lens 20 uses a first wavelength of 620nm (λ1), a second wavelength of 550nm (λ2), and a third wavelength of 460nm (λ3) at its wide-angle end, along with relative image heights of 0.00, 0.20, 0.40, 0.60, 0.80, and 1.00, to simulate the ray aberration diagram shown in Figure 2C. The meridional aberration characteristic curve and the sagittal aberration characteristic curve are observed, and the resulting aberration values ​​are controlled within the range of (-0.01mm, 0.02mm). The telephoto end of the wide-angle zoom projection lens 20 uses a first wavelength of 620nm (λ1), a second wavelength of 550nm (λ2), and a third wavelength of 460nm (λ3), along with relative image heights of 0.00, 0.20, 0.40, 0.60, 0.80, and 1.00, respectively, to simulate the ray aberration diagram shown in Figure 2D. The meridional aberration characteristic curve and the sagittal aberration characteristic curve are observed, and the resulting aberration values ​​are controlled within the range of (-0.03mm, 0.02mm). Furthermore, referring to Figures 3A and 3B, the wide-angle zoom projection lens 30 of Embodiment 3 of the present invention comprises, from the magnification side to the reduction side, a first lens group 31 with negative refractive power, a second lens group 32, a third lens group 33 with positive refractive power, a fourth lens group 34 with positive refractive power, a fifth lens group 35 with positive refractive power, and a sixth lens group 36 with positive refractive power, as well as a prism P. The lens is also provided with an aperture S3 between the third and fourth lens groups 34 and 35 (or within the fifth lens group 35), and the F-value of the aperture S3 is between 1.8 and 1.94. During zooming, the first lens group 31 and the sixth lens group 36 are fixed, and the second to fifth lens groups 32, 33, 34, and 35 move along the optical axis to achieve a change in focal length. The foremost lens 3L1 of the first lens group 31, closest to the magnification side of the lens, is a negative refractive power aspherical lens used to achieve a wide-angle effect. The reduction side of the lens has a telecentric characteristic. Among them, Ww / Dw=1.981, |ft / fw|=1.271, |f1 / fw|=1.382, |f5 / fw|=32.652, Bf / fw=4.709, CA / IHm=8.698, Ww is the width of the projected image at the wide-angle end, Dw is the projection distance at the wide-angle end, ft is the focal length of the entire lens at the telephoto end, fw is the focal length of the entire lens at the wide-angle end, f1 is the focal length of the first lens group, f5 is the focal length of the fifth lens group, Bf is the back focal length when converted to air, CA is the effective diameter of the foremost lens, and IHm is the maximum image height on the reduction side of the lens. The lens design parameters of the wide-angle zoom projection lens 30 are shown in Tables 3A, 3B, and 3C. Among them, 3L1R1 is the magnifying side surface (R1) of the foremost (first) lens (3L1), 3L1R2 is the reducing side surface (R2) of the first lens (3L1), 3L2R1 is the magnifying side surface (R1) of the second lens (3L2), 3L2R2 is the reducing side surface (R2) of the second lens (3L2), ... 3L17R1 is the magnifying side surface (R1) of the seventeenth lens (3L17), 3L17R2 is the reducing side surface (R2) of the seventeenth lens (3L17), and so on. However, the tenth lens (3L10), the eleventh lens (3L11), and the twelfth lens (3L12) can form a cemented lens, and the fourteenth lens (3L14) and the fifteenth lens (3L15) can form a cemented lens. Table 3A Table 3B Table 3C The wide-angle zoom projection lens 30 uses a first wavelength of 620nm (λ1), a second wavelength of 550nm (λ2), and a third wavelength of 460nm (λ3) at its wide-angle end, along with relative image heights of 0.00, 0.20, 0.40, 0.60, 0.80, and 1.00, to simulate the ray aberration diagram shown in Figure 3C. The meridional aberration characteristic curve and the sagittal aberration characteristic curve are observed, and the resulting aberration values ​​are controlled within the range of (-0.03mm, 0.03mm). The telephoto end of the wide-angle zoom projection lens 20 uses a first wavelength of 620nm (λ1), a second wavelength of 550nm (λ2), and a third wavelength of 460nm (λ3), along with relative image heights of 0.00, 0.20, 0.40, 0.60, 0.80, and 1.00, respectively, to simulate the ray aberration diagram of Figure 3D. The meridional aberration characteristic curve and the sagittal aberration characteristic curve are observed, and the resulting aberration values ​​are controlled within the range of (-0.03mm, 0.02mm). Furthermore, referring to Figures 4A and 4B, the wide-angle zoom projection lens 40 of Embodiment 4 of the present invention comprises, from the magnification side to the reduction side, a first lens group 41 with negative refractive power, a second lens group 42, a third lens group 43 with positive refractive power, a fourth lens group 44 with positive refractive power, and a fifth lens group 45 with positive refractive power, as well as a prism P. The lens is also provided with an aperture S4 between the third and fourth lens groups 43 and 44 (or within the four lens groups 44), and the F-value of the aperture S4 is between 1.8 and 1.94. During zooming, the first lens group 41 and the fifth lens group 45 are fixed, and the second to fourth lens groups 42, 43, and 44 move along the optical axis to achieve a change in focal length. The first lens group 41 is closest to the fifth lens group 45. The foremost lens 4L1 on the magnifying side of the lens is a negative refractive power aspherical lens used to achieve a wide-angle effect. The reducing side of the lens has a telecentric characteristic. Among them, Ww / Dw=1.977, |ft / fw|=1.275, |f1 / fw|=4.363, |f4 / fw|=24.203, Bf / fw=4.697, CA / IHm=8.641, Ww is the width of the projected image at the wide-angle end, Dw is the projection distance at the wide-angle end, ft is the focal length of the entire lens at the telephoto end, fw is the focal length of the entire lens at the wide-angle end, f1 is the focal length of the first lens group, f4 is the focal length of the fourth lens group, Bf is the back focal length when converted to air, CA is the effective diameter of the foremost lens, and IHm is the maximum image height on the reducing side of the lens. The lens design parameters of the wide-angle zoom projection lens 40 are shown in Tables 4A, 4B, and 4C. Among them, 4L1R1 is the magnifying side surface (R1) of the foremost (first) lens (4L1), 4L1R2 is the reducing side surface (R2) of the first lens (4L1), 4L2R1 is the magnifying side surface (R1) of the second lens (4L2), 4L2R2 is the reducing side surface (R2) of the second lens (4L2), ... 4L17R1 is the magnifying side surface (R1) of the seventeenth lens (4L17), 4L17R2 is the reducing side surface (R2) of the seventeenth lens (4L17), and so on. However, the tenth lens (4L10), the eleventh lens (4L11), and the twelfth lens (4L12) can form a cemented lens, and the fourteenth lens (4L14) and the fifteenth lens (4L15) can form a cemented lens. Table 4A Table 4B Table 4C The wide-angle zoom projection lens 40 uses a first wavelength of 620nm (λ1), a second wavelength of 550nm (λ2), and a third wavelength of 460nm (λ3) at its wide-angle end to simulate the ray aberration diagram shown in Figure 4C with relative image heights of 0.00, 0.20, 0.40, 0.60, 0.80, and 1.00, respectively. It also simulates the ray aberration diagram shown in Figure 3D with relative field heights of 0.40, 0.20, and 0.00. The meridional aberration characteristic curve and the sagittal aberration characteristic curve are observed, and the resulting aberration values ​​are controlled within (- Within the range of 0.02mm, 0.02mm; the telephoto end of the wide-angle zoom projection lens 20 uses a first wavelength of 620nm (λ1), a second wavelength of 550nm (λ2), and a third wavelength of 460nm (λ3), with relative image heights of 0.00, 0.20, 0.40, 0.60, 0.80, and 1.00 respectively to simulate the ray aberration diagram of Figure 4D, observe the meridional aberration characteristic curve and the sagittal aberration characteristic curve, and the generated aberration value is controlled within the range of (-0.02mm, 0.01mm). Furthermore, referring to Figures 5A and 5B, the wide-angle zoom projection lens 50 of Embodiment 5 of the present invention comprises, from the magnification side to the reduction side, a first lens group 51 with negative refractive power, a second lens group 52, a third lens group 53 with positive refractive power, a fourth lens group 54 with positive refractive power, and a fifth lens group 55 with positive refractive power, as well as a prism P. The lens is also provided with an aperture S5 between the third and fourth lens groups 53 and 54 (or within the four lens groups 54), and the F-value of the aperture S5 is between 1.8 and 1.85. During zooming, the first lens group 51 and the fifth lens group 55 are fixed, and the second to fourth lens groups 52, 53, and 54 move along the optical axis to achieve a change in focal length. The first lens group 51 is closest to the fifth lens group 55. The foremost lens 5L1 on the magnifying side of the lens is a negative refractive power aspherical lens used to achieve a wide-angle effect. The reducing side of the lens has a telecentric characteristic. Among them, Ww / Dw=1.989, |ft / fw|=1.088, |f1 / fw|=3.242, |f4 / fw|=47.374, Bf / fw=4.698, CA / IHm=8.458, Ww is the width of the projected image at the wide-angle end, Dw is the projection distance at the wide-angle end, ft is the focal length of the entire lens at the telephoto end, fw is the focal length of the entire lens at the wide-angle end, f1 is the focal length of the first lens group, f4 is the focal length of the fourth lens group, Bf is the back focal length when converted to air, CA is the effective diameter of the foremost lens, and IHm is the maximum image height on the reducing side of the lens. The lens design parameters of the wide-angle zoom projection lens 50 are shown in Tables 5A, 5B, and 5C. Among them, 5L1R1 is the magnifying side surface (R1) of the foremost (first) lens (5L1), 5L1R2 is the reducing side surface (R2) of the first lens (5L1), 5L2R1 is the magnifying side surface (R1) of the second lens (5L2), 5L2R2 is the reducing side surface (R2) of the second lens (5L2), ... 5L17R1 is the magnifying side surface (R1) of the seventeenth lens (5L17), 5L17R2 is the reducing side surface (R2) of the seventeenth lens (5L17), and so on. However, the tenth lens (5L10), the eleventh lens (5L11), and the twelfth lens (5L12) can form a cemented lens, and the fourteenth lens (5L14) and the fifteenth lens (5L15) can form a cemented lens. Table 5A Table 5B Table 5C The wide-angle zoom projection lens 50 uses a first wavelength of 620nm (λ1), a second wavelength of 550nm (λ2), and a third wavelength of 460nm (λ3) at its wide-angle end, along with relative image heights of 0.00, 0.20, 0.40, 0.60, 0.80, and 1.00, to simulate the ray aberration diagram shown in Figure 5C. The meridional aberration characteristic curve and the sagittal aberration characteristic curve are observed, and the resulting aberration values ​​are controlled within the range of (-0.01mm, 0.02mm). The telephoto end of the wide-angle zoom projection lens 20 uses a first wavelength of 620nm (λ1), a second wavelength of 550nm (λ2), and a third wavelength of 460nm (λ3), along with relative image heights of 0.00, 0.20, 0.40, 0.60, 0.80, and 1.00, respectively, to simulate the ray aberration diagram of Figure 5D. The meridional aberration characteristic curve and the sagittal aberration characteristic curve are observed, and the resulting aberration values ​​are controlled within the range of (-0.02mm, 0.02mm). Based on this configuration, the foremost (first) lens 1L1 / 2L1 / 3L1 / 4L1 / 5L1 of this invention is a negative refractive power aspherical lens to achieve a wide-angle effect. The second lens group 12 / 22 / 32 / 42 / 52, the third lens group 13 / 23 / 33 / 43 / 53, the fourth lens group 14 / 24 / 34 / 44 / 54, and the fifth lens group 15 / 25 / 35 are designed as movable groups, which can meet the requirements of zoom projection. At the same time, the aberrations, field curvature, distortion, and lateral chromatic aberration of the wide-angle zoom projection lenses 10, 20, 30, 40, and 50 at the wide-angle and telephoto ends can be controlled within a small range. Therefore, this invention has the effect of simultaneously meeting the requirements of high brightness, wide-angle, and zoom projection, and achieving high resolution. In conclusion, the technical means disclosed in this invention do indeed possess the requirements for invention patents, namely "novelty," "progressiveness," and "industrial applicability." I humbly request that Your Excellency grant me a patent to encourage invention. I am deeply grateful for your kindness. However, the above-disclosed drawings and descriptions are merely preferred embodiments of the present invention. Modifications or equivalent changes made by those skilled in the art within the spirit and scope of this application should still be included within the scope of the patent application. 10, 20, 30, 40, 50: Wide-angle zoom projection lens; 11, 21, 31, 41, 51: First lens group; 12, 22, 32, 42, 52: Second lens group; 13, 23, 33, 43, 53: Third lens group; 14, 24, 34, 44, 54: Fourth lens group; 15, 25, 35, 45, 55: Fifth lens group; 16, 26: Sixth lens group; 1L1, 2L1, 3L1, 4L1, 5L1: Foremost (first...) (I) Lenses 1L2, 2L2, 3L2, 4L2, 5L2; Second lens 1L3, 2L3, 3L3, 4L3, 5L3; Third lens 1L4, 2L4, 3L4, 4L4, 5L4; Fourth lens 1L5, 2L5, 3L5, 4L5, 5L5; Fifth lens 1L6, 2L6, 3L6, 4L6, 5L6; Sixth lens 1L7, 2L7, 3L7, 4L7, 5L7; Seventh lens 1L8, 2L8, 3L... 8, 4L8, 5L8: Eighth lens; 1L9, 2L9, 3L9, 4L9, 5L9: Ninth lens; 1L10, 2L10, 3L10, 4L10, 5L10: Tenth lens; 1L11, 2L11, 3L11, 4L11, 5L11: Eleventh lens; 1L12, 2L12, 3L12, 4L12, 5L12: Twelfth lens; 1L13, 2L13, 3L13, 4L13, 5L13: Thirteenth lens. L14, 2L14, 3L14, 4L14, 5L14: Fourteenth lens; 1L15, 2L15, 3L15, 4L15, 5L15: Fifteenth lens; 1L16, 2L16, 3L16, 4L16, 5L16: Sixteenth lens; 1L17, 2L17, 3L17, 4L17, 5L17: Seventeenth lens; 1L18, 2L18: Eighteenth lens; S1, S2, S3, S4, S5, S6: Aperture; P: Prism. Figure 1A is a schematic diagram of the lens configuration at the wide-angle end of Embodiment 1 of the present invention. Figure 1B is a schematic diagram of the lens configuration at the telephoto end of Embodiment 1 of the present invention. Figure 1C is a diagram of ray aberration at the wide-angle end of Embodiment 1 of the present invention. Figure 1D is a diagram of ray aberration at the telephoto end of Embodiment 1 of the present invention. Figure 2A is a schematic diagram of the lens configuration at the wide-angle end of Embodiment 2 of the present invention. Figure 2B is a schematic diagram of the lens configuration at the telephoto end of Embodiment 2 of the present invention. Figure 2C is a diagram of ray aberration at the wide-angle end of Embodiment 1 of the present invention. Figure 2D is a diagram of ray aberration at the telephoto end of Embodiment 1 of the present invention. Figure 3A is a schematic diagram of the lens configuration at the wide-angle end of Embodiment 3 of the present invention. Figure 3B is a schematic diagram of the lens configuration at the telephoto end of Embodiment 3 of the present invention. Figure 3C is a diagram of ray aberration at the wide-angle end of Embodiment 1 of the present invention. Figure 3D is a diagram of ray aberration at the telephoto end of Embodiment 1 of the present invention. Figure 4A is a schematic diagram of the lens configuration at the wide-angle end of Embodiment 4 of the present invention. Figure 4B is a schematic diagram of the lens configuration at the telephoto end of Embodiment 4 of the present invention. Figure 4C is a light aberration diagram at the wide-angle end of Embodiment 1 of the present invention. Figure 4D is a light aberration diagram at the telephoto end of Embodiment 1 of the present invention. Figure 5A is a schematic diagram of the lens configuration at the wide-angle end of Embodiment 5 of the present invention. Figure 5B is a schematic diagram of the lens configuration at the telephoto end of Embodiment 5 of the present invention. Figure 5C is a light aberration diagram at the wide-angle end of Embodiment 1 of the present invention. Figure 5D is a light aberration diagram at the telephoto end of Embodiment 1 of the present invention. 10: Wide-angle zoom projection lens 11: First lens group 12: Second lens group 13: Third lens group 14: Fourth lens group 15: Fifth lens group 16: Sixth lens group 1L1: Foremost lens 1L2: Second lens 1L3: Third lens 1L4: Fourth Lens 1L5: Fifth Lens 1L6: Sixth Lens 1L7: Seventh Lens 1L8: Eighth Lens 1L9: Ninth Lens 1L10: Tenth Lens 1L11: Eleventh Lens 1L12: Twelfth Lens 1L13: The thirteenth lens 1L14: Fourteenth Lens 1L15: The fifteenth lens 1L16: Sixteenth Lens 1L17: The Seventeenth Lens 1L18: The eighteenth lens S1: Aperture P: Prism

Claims

1. A wide-angle zoom projection lens, comprising six lens groups arranged sequentially from the magnification side to the reduction side of the lens: a first lens group with negative refractive power, a second lens group, a third lens group with positive refractive power, a fourth lens group with positive refractive power, a fifth lens group with positive refractive power, and a sixth lens group with positive refractive power, wherein the lens is also provided with an aperture; during zooming, the first lens group and the sixth lens group are fixed, and the second to fifth lens groups move along the optical axis to achieve a change in focal length; the foremost lens of the first lens group closest to the magnification side of the lens is a negative refractive power aspherical lens to achieve a wide-angle effect, the reduction side of the lens has a telecentric characteristic, and 1.3≤Ww / Dw≤2.5, where Ww is the width of the projected image at the wide-angle end, and Dw is the projection distance at the wide-angle end.

2. The wide-angle zoom projection lens as described in claim 1, wherein, 1.05≤|ft / fw|≤1.7, where ft is the focal length of the entire lens at the telephoto end and fw is the focal length of the entire lens at the wide-angle end.

3. The wide-angle zoom projection lens as described in claim 1, wherein, The aperture is located between or within the fourth and fifth lens groups, and the F-number of the aperture is between 1.7 and 2.

6.

4. The wide-angle zoom projection lens as described in claim 1, wherein, The first lens group has at least one glass lens with a refractive index ≥1.75 and at least one glass lens with an Abbe number ≥55, and the fifth lens group has at least one cemented lens, at least one glass lens with a refractive index ≥1.75 and at least one glass lens with an Abbe number ≥60.

5. The wide-angle zoom projection lens as described in claim 1, wherein, 1.2≤|f1 / fw|≤1.7, 4.5≤|f5 / fw|≤35.0, where fw is the focal length of the entire lens at the wide-angle end, f1 is the focal length of the first lens group, and f5 is the focal length of the fifth lens group.

6. The wide-angle zoom projection lens as described in claim 1, wherein, 4.0≤Bf / fw≤5.0, where fw is the focal length of the entire lens at the wide-angle end, and Bf is the back focal length converted to air.

7. The wide-angle zoom projection lens as described in claim 1, wherein, CA / IHm≤12, where CA is the effective diameter of the foremost lens and IHm is the maximum image height on the reduced side of the lens.

8. A wide-angle zoom projection lens, using five lens groups arranged sequentially from the magnification side to the reduction side of the lens: a first lens group with negative refractive power, a second lens group, a third lens group with positive refractive power, a fourth lens group with positive refractive power, and a fifth lens group with positive refractive power, and the lens is also provided with an aperture; during zooming, the first lens group and the fifth lens group are fixed, and the second to fourth lens groups move along the optical axis to achieve a change in focal length; the foremost lens of the first lens group closest to the magnification side of the lens is a negative refractive power aspherical lens to achieve a wide-angle effect, the reduction side of the lens has a telecentric characteristic, and 1.3≤Ww / Dw≤2.5, where Ww is the width of the projected image at the wide-angle end, and Dw is the projection distance at the wide-angle end.

9. The wide-angle zoom projection lens as described in claim 8, wherein, 1.05≤|ft / fw|≤1.3, where ft is the focal length of the entire lens at the telephoto end and fw is the focal length of the entire lens at the wide-angle end.

10. The wide-angle zoom projection lens as described in claim 8, wherein, The aperture is located between or within the third and fourth lens groups, and the F-number of the aperture is between 1.7 and 2.

6.

11. The wide-angle zoom projection lens as described in claim 8, wherein, The first lens group has at least one glass lens with a refractive index ≥1.75 and at least one glass lens with an Abbe number ≥55, and the fourth lens group has at least one cemented lens, at least one glass lens with a refractive index ≥1.75 and at least one glass lens with an Abbe number ≥60.

12. The wide-angle zoom projection lens as described in claim 8, wherein, 3≤|f1 / fw|≤5, 4.5≤|f4 / fw|≤50.0, where fw is the focal length of the entire lens at the wide-angle end, f1 is the focal length of the first lens group, and f4 is the focal length of the fourth lens group.

13. The wide-angle zoom projection lens as described in claim 8, wherein, 4.0≤Bf / fw≤5.0, where fw is the focal length of the entire lens at the wide-angle end, and Bf is the back focal length converted to air.

14. The wide-angle zoom projection lens as described in claim 8, wherein, CA / IHm≤12, where CA is the effective diameter of the foremost lens and IHm is the maximum image height on the reduced side of the lens.

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