3D printing projection lens and 3D printing projection light machine
Patent Information
- Application Number
- CN202522006689.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-09-17
- Publication Date
- 2026-09-15
- Estimated Expiration
- 2035-09-17
AI Technical Summary
[0051]This application provides a 3D printed projection lens and a 3D printed projection optical engine. The 3D printed projection lens is composed of three single lenses arranged sequentially along the optical path: a front group, a middle group, and a rear group. Through the division of labor and cooperation of multiple lens groups, aberrations are corrected in a segmented manner, which enables the design of a high-performance optical system. This allows the 3D printed projection lens to have better performance, thereby enabling the 3D printed projection optical engine to achieve clear imaging at a lower cost, which is beneficial for industrial production and application.
Smart Images
Figure CN224758797U_ABST
Abstract
Description
Technical Field
[0001] This application belongs to the field of projection lens technology, and particularly relates to a 3D printed projection lens and a 3D printed projection optical engine. Background Technology
[0002] The 3D printing projection optical engine can precisely cure liquid resin using ultraviolet light, achieving micron-level resolution printing. It can also improve the phenomenon that when the thickness of the cured liquid resin layer is large, the cured resin on the curved surface will show obvious stepped texture due to the height difference of each layer of cured resin. This greatly improves the problems of insufficient surface quality and precision in 3D printing.
[0003] Existing 3D printed projection optical engines are typically encapsulated within a housing. Therefore, heat dissipation is crucial for the high-power light source inside these engines, as good heat dissipation minimizes thermal drift and reduces the impact on imaging accuracy. Simultaneously, the display chip's micromirror array is temperature-sensitive, also requiring heat dissipation to maintain its stability.
[0004] Currently, to improve image quality, a larger galvanometer scanning range is required, which leads to a larger size of 3D printed projection optical engines. However, the large size of 3D printed projection optical engines results in higher mold-making costs. Therefore, there is an urgent need to provide a new type of 3D printed projection optical engine that can achieve high image quality using a single lens and its combination in a 3D printed projection lens, while also having lower mold-making costs. Utility Model Content
[0005] In view of this, embodiments of this application provide a 3D printed projection lens and a 3D printed projection optical engine. The 3D printed projection lens achieves excellent imaging quality under strict space constraints and at a low cost by combining multiple single lenses and using a segmented aberration correction method.
[0006] A first aspect of this application provides a 3D printed projection lens, comprising: a front group, a middle group, and a rear group arranged sequentially from the object side to the image side along the optical path direction, wherein the front group and the middle group are separate and spaced apart, and the middle group and the rear group are separate and spaced apart.
[0007] Along the optical path direction, the front group includes at least one negative power lens and two positive power lenses;
[0008] The middle group includes at least two negative power lenses and one positive power lens;
[0009] The rear group includes at least one set of combined optical power lenses arranged in a positive-negative-positive configuration, and two positive optical power lenses.
[0010] In some embodiments, the negative power lens in the front group is biconcave in shape;
[0011] And / or, the positive power lens in the middle group is biconvex in shape.
[0012] In some embodiments, the front group is provided with a first negative power lens, a second positive power lens and a third positive power lens arranged sequentially along the optical path direction;
[0013] The refractive index of the material of the first negative power lens is less than or equal to 1.65, and the Abbe number of the material of the first negative power lens is less than or equal to 36.
[0014] And / or, the refractive index of the material of the second positive focal length lens is greater than or equal to 1.8, and the Abbe number of the material of the second positive focal length lens is less than or equal to 40;
[0015] And / or, the refractive index of the material of the third positive power lens is less than or equal to 1.65, and the Abbe number of the material of the third positive power lens is greater than or equal to 60.
[0016] In some embodiments, the middle group is arranged sequentially along the optical path direction with a fourth negative power lens, a fifth negative power lens and a sixth positive power lens;
[0017] The refractive index of the material of the fourth negative power lens is less than or equal to 1.65, and the Abbe number of the material of the fourth negative power lens is greater than or equal to 60.
[0018] And / or, the refractive index of the material of the fifth negative power lens is less than or equal to 1.65, and the Abbe number of the material of the fifth negative power lens is greater than or equal to 60;
[0019] And / or, the refractive index of the material of the sixth positive focal power lens is greater than or equal to 1.65 and less than or equal to 1.75, and the Abbe number of the material of the sixth positive focal power lens is greater than or equal to 50 and less than or equal to 60.
[0020] In some embodiments, the rear group includes an aperture stop, a seventh positive power lens, an eighth negative power lens, a ninth positive power lens, a tenth positive power lens, and an eleventh positive power lens arranged sequentially along the optical path direction.
[0021] The refractive index of the material of the seventh spherical positive power lens is less than or equal to 1.65, and the Abbe number of the material of the seventh spherical positive power lens is greater than or equal to 60.
[0022] And / or, the refractive index of the material of the eighth negative power lens is greater than or equal to 1.65, and the Abbe number of the material of the eighth negative power lens is less than or equal to 36;
[0023] And / or, the refractive index of the material of the ninth positive focal power lens is greater than or equal to 1.65 and less than or equal to 1.75, and the Abbe number of the material of the ninth positive focal power lens is greater than or equal to 50 and less than or equal to 60;
[0024] And / or, the refractive index of the material of the tenth positive power lens is less than or equal to 1.65, and the Abbe number of the material of the tenth positive power lens is greater than or equal to 60;
[0025] And / or, the refractive index of the material of the eleventh positive power lens is less than or equal to 1.65, and the Abbe number of the material of the eleventh positive power lens is greater than or equal to 60.
[0026] In some embodiments, the front group comprises a first spherical negative power lens, a second spherical positive power lens, and a third spherical positive power lens arranged sequentially from the object side to the image side along the optical path direction;
[0027] The middle group consists of a fourth spherical negative power lens, a fifth spherical negative power lens, and a sixth spherical positive power lens arranged sequentially from the object side to the image side along the optical path direction.
[0028] The rear group consists of an aperture stop, a seventh spherical positive power lens, an eighth spherical negative power lens, a ninth spherical positive power lens, a tenth spherical positive power lens, and an eleventh spherical positive power lens arranged sequentially from the object side to the image side along the optical path direction.
[0029] In some embodiments, the focal length of the 3D printed projection lens is 24mm to 36mm;
[0030] And / or, the focal length of the front group is 82mm to 124mm;
[0031] And / or, the focal length of the middle group is -236mm to -157mm;
[0032] And / or, the focal length of the rear group is 39mm to 58mm;
[0033] And / or, the focal length of the first spherical negative power lens is -124mm to -82mm;
[0034] And / or, the focal length of the second spherical positive power lens is 161mm to 241mm;
[0035] And / or, the focal length of the third spherical positive power lens is 71mm to 107mm;
[0036] And / or, the focal length of the fourth spherical negative power lens is -95mm to -63mm;
[0037] And / or, the focal length of the fifth spherical negative power lens is -51mm to -34mm;
[0038] And / or, the focal length of the sixth spherical positive power lens is 52mm to 78mm;
[0039] And / or, the focal length of the seventh spherical positive power lens is 62mm to 94mm;
[0040] And / or, the focal length of the eighth spherical negative power lens is -52mm to -34mm;
[0041] And / or, the focal length of the ninth spherical positive power lens is 68mm to 102mm;
[0042] And / or, the focal length of the tenth spherical positive power lens is 71mm to 106mm;
[0043] And / or, the focal length of the eleventh spherical positive power lens is 134mm to 202mm.
[0044] In some embodiments, the 3D printed projection lens is composed of 12 single lenses arranged in a single lens;
[0045] And / or, the 3D-printed projection lens is used to operate in the optical wavelength range of 370nm to 440nm;
[0046] And / or, the aperture number of the 3D printed projection lens is 1.7 to 1.9;
[0047] And / or, the working distance of the 3D printing projection lens is 200mm to 1000mm.
[0048] A second aspect of this application provides a 3D printed projection optical engine, including the 3D printed projection lens described above.
[0049] In some embodiments, the 3D printed projection optical engine further includes: a display chip, a display chip protective glass, a galvanometer, and a prism equivalent plate, wherein the display chip, the display chip protective glass, the galvanometer, and the prism equivalent plate are arranged sequentially from the image side to the object side along the optical path direction.
[0050] Compared with the prior art, this application has the following technical effects:
[0051] This application provides a 3D printed projection lens and a 3D printed projection optical engine. The 3D printed projection lens is composed of three single lenses arranged sequentially along the optical path: a front group, a middle group, and a rear group. Through the division of labor and cooperation of multiple lens groups, aberrations are corrected in a segmented manner, which enables the design of a high-performance optical system. This allows the 3D printed projection lens to have better performance, thereby enabling the 3D printed projection optical engine to achieve clear imaging at a lower cost, which is beneficial for industrial production and application. Attached Figure Description
[0052] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0053] Figure 1 This is a schematic diagram of the structure of a 3D printed projection lens provided in an embodiment of this application;
[0054] Figure 2 This is a schematic diagram of the front assembly of a 3D printed projection lens provided in an embodiment of this application;
[0055] Figure 3 This is a schematic diagram of the structure of the middle group in a 3D printed projection lens provided in an embodiment of this application;
[0056] Figure 4 This is a schematic diagram of the rear element in a 3D printed projection lens provided in an embodiment of this application;
[0057] Figure 5 yes Figure 1 A schematic diagram of the surfaces of a 3D-printed projection lens;
[0058] Figure 6 This is a schematic diagram of the light path of a 3D printed projection lens provided in an embodiment of this application;
[0059] Figure 7 This is a schematic diagram of an actual scene where light passes through the 3D printing projection lens provided in the embodiments of this application;
[0060] Figure 8 This is an MTF curve of a 3D printed projection lens image on a display chip, provided in an embodiment of this application.
[0061] Figure label:
[0062] 300 - 3D printing projection lens, 301 - Display chip, 302 - Display chip protective glass, 303 - Galvanometer, 304 - Prism equivalent plate, 310 - Front group, 311 - First spherical negative power lens, 312 - Second spherical positive power lens, 313 - Third spherical positive power lens, 320 - Middle group, 321 - Fourth spherical negative power lens, 322 - Fifth spherical negative power lens, 323 - Sixth spherical positive power lens, 330 - Rear group, 331 - Aperture stop, 332 - Seventh spherical positive power lens, 333 - Eighth spherical negative power lens, 334 - Ninth spherical positive power lens, 335 - Tenth spherical positive power lens, 336 - Eleventh spherical positive power lens, 1 - Object plane. Detailed Implementation
[0063] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present application.
[0064] The term "comprising" and any variations thereof in the specification, claims, and accompanying drawings are intended to cover a non-exclusive inclusion. For example, a process, method, system, product, or apparatus that comprises a series of steps or units is not limited to the steps or units listed, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to such processes, methods, products, or apparatus.
[0065] Furthermore, the terms "first," "second," "third," "fourth," "fifth," "sixth," "seventh," "eighth," and "ninth" are used to distinguish different objects, rather than to describe a specific order.
[0066] The term "at least one" means "one or more".
[0067] The term "electrical connection" can refer to a direct electrical connection between two components, or an electrical connection between two components via one or more other components; "electrical connection" can refer to an electrical connection via a wire, or an electrical connection via a radio signal.
[0068] Furthermore, the utility model proposed in this application can be fully understood by the following specific embodiments, enabling those skilled in the art to complete it. However, the embodiments of the application are not limited to the following embodiments. Those skilled in the art can deduce other embodiments based on the disclosed embodiments, and such embodiments should all fall within the scope of this utility model. For example, slightly separating the closely spaced positive and negative lenses while maintaining a similar single lens profile, or simply splitting a positive power lens into two positive power lenses, should all be considered appropriate extensions of this utility model and within the protection scope of this utility model.
[0069] Example 1
[0070] This application provides a 3D printed projection lens, for reference... Figures 1 to 5 As shown, the 3D printing projection lens 300 in this embodiment may include: a front group 310, a middle group 320 and a rear group 330 arranged sequentially from the object side to the image side along the optical path direction, wherein the front group 310 and the middle group 320 are separate and spaced apart, and the middle group 320 and the rear group 330 are separate and spaced apart.
[0071] Please refer to the following: Figures 1 to 5 As shown, along the optical path, the front group 310 includes at least one negative power lens and two positive power lenses, the middle group 320 includes at least two negative power lenses and one positive power lens, and the rear group 330 includes at least an aperture stop, a set of combined lenses arranged in a "positive-negative-positive" pattern, and two positive power lenses.
[0072] It should be noted that in the "positive-negative-positive" arrangement of the combined lenses in the rear group 330, the positive power lens, negative power lens, and positive power lens are close together.
[0073] In practical applications, the arrangement of at least one negative power lens and two positive power lenses in the front group 310 can be, for example, negative-positive-positive-negative-positive; or negative-positive-positive-negative-positive-positive; or negative-positive-positive-negative-positive-positive, etc. There are many combinations, and no specific limitation is made here.
[0074] As an example, the front group 310 may include a first negative power lens, a second positive power lens, and a third positive power lens arranged sequentially along the optical path. By first using a negative power lens as the object-side primary lens, not only can the system's field of view be effectively expanded, but distortion can also be significantly suppressed, ensuring sharp edge image quality. At the same time, the light divergence characteristics of this negative power lens provide optimized optical path control freedom for subsequent lens groups, enabling the two subsequent positive power lenses to achieve synergistic optical compensation. Furthermore, these two positive power lenses are precisely matched and form a converging dual engine, which not only completes primary beam shaping but also delivers a uniform light field to the middle group 320 with a wavefront accuracy of λ / 4.
[0075] In practical applications, the arrangement of at least two negative power lenses and one positive power lens in the middle group 320 can be, for example, negative-negative-positive-negative-negative-positive, etc., without specific limitations.
[0076] As an example, the middle group 320 may include a fourth negative power lens, a fifth negative power lens, and a sixth positive power lens arranged sequentially along the optical path. By using two negative power lenses to form a double negative power lens, the image plane can be further flattened. Then, when light passes through the positive power lens, the positive power lens and the two negative power lenses can produce opposite aberrations, and most of the opposite aberrations can cancel each other out.
[0077] It should be understood that in each group of "positive-negative-positive" combined lenses in the rear group 330, the proximity of the positive power lens, negative power lens, and positive power lens means that the positive power lens, negative power lens, and positive power lens are just next to each other, and there is air between any adjacent "positive-negative" or "negative-positive" pairs.
[0078] As an example, the rear group 330 may include: an aperture stop 331, a seventh positive power lens, an eighth negative power lens, a ninth positive power lens, a tenth positive power lens, and an eleventh positive power lens arranged sequentially along the optical path. By placing the aperture stop 331 at the front end of the rear group 330, the aperture stop 331 can effectively suppress edge field distortion rays and reduce higher-order aberrations. Simultaneously, a progressive power distribution scheme is adopted behind the aperture stop 331. Specifically, a positive power lens is used as the first positive power lens, mainly used to correct axial chromatic aberration and control the principal ray to enter the image plane at a near-perpendicular angle. Then, the negative power lens actively adjusts the image plane curvature using its negative power characteristics to improve field curvature aberration. Next, another positive power lens is used, followed by... Two positive power lenses form a compound positive power lens group, which can keep the total optical power of the system positive, improve the uniformity of illumination at the edge of the field of view, and reduce the light deflection angle step by step, significantly reducing spherical aberration and coma, and also providing additional degrees of freedom for chromatic aberration correction. In addition, the last lens is a positive power lens, which serves as the terminal lens of the rear group 330 and is located closest to the prism equivalent plate 304, thus bearing the main positive power and ensuring that a high-quality converging real image is formed on the display chip, such as the tilted digital micromirror device (DMD), as the imaging surface of the display chip. At the same time, this positive power lens, as the last optical interface, matches the optical characteristics of the prism equivalent plate 304, which can reduce interface reflection loss and work with all the lenses in front of it to complete the aberration balance of the entire optical system.
[0079] It should be noted that the above-mentioned direction along the optical path from the object side to the image side is the opposite direction according to the order of light propagation. The optical path direction in the embodiment of this application is... Figures 1 to 5 The OX direction shown is the direction from O to X.
[0080] In practical applications, the front group 310 and the middle group 320, which are arranged sequentially from the object side to the image side along the optical path, can be separated by an air gap, meaning that the front group 310 and the middle group 320 do not contact each other. Similarly, the middle group 320 and the rear group 330 can also be separated by an air gap, meaning that the middle group 320 and the rear group 330 do not contact each other.
[0081] The 3D printing projection lens provided in this application embodiment is a large-volume 3D printing projection lens. It corrects aberrations by using a segmented approach. Specifically, it is composed of three lens groups along the optical path: a front group, a middle group, and a rear group. Through the division of labor and cooperation of multiple single lenses, that is, through the arrangement and combination of multiple negative power lenses and multiple positive power lenses, aberrations of different fields of view and apertures are corrected in stages. The optical power is highly dispersed, and the sensitivity of a single lens is reduced. This enables high-precision printing at the micron level and can improve the problem of obvious stepped textures on curved surfaces caused by height differences in each layer of cured liquid resin when the layer thickness is large. The image quality is better.
[0082] Therefore, the large-volume, cost-effective 3D printed projection lens in this embodiment has better performance and has broad application prospects in fields such as micro-nano manufacturing and biomedicine.
[0083] In some embodiments, reference Figure 2 As shown, in the 3D printed projection lens 300 provided in this application embodiment, the front group 310 may include: along the optical path direction ( Figure 2 The first spherical negative power lens 311, the second spherical positive power lens 312, and the third spherical positive power lens 313 are arranged sequentially (in the direction of the OX arrow in the image).
[0084] Furthermore, the first spherical negative power lens 311 can specifically be a biconcave spherical negative power lens. The refractive index Nd1 of the material of the first spherical negative power lens 311 is less than or equal to 1.65, and the Abbe number Vd1 of the material of the first spherical negative power lens 311 is less than or equal to 36. Thus, the material of the first spherical negative power lens 311 has a low refractive index and a low Abbe number.
[0085] The refractive index Nd2 of the material of the second spherical positive power lens 312 is greater than or equal to 1.8, and the Abbe number Vd2 of the material of the second spherical positive power lens 312 is less than or equal to 40. Therefore, the material of the second spherical positive power lens 312 has a high refractive index and a low Abbe number.
[0086] The refractive index Nd3 of the material of the third spherical positive power lens 313 is less than or equal to 1.65, and the Abbe number Vd3 of the material of the third spherical positive power lens 313 is greater than or equal to 60. Therefore, the material of the third spherical positive power lens 313 has a low refractive index and a high Abbe number.
[0087] It should be noted that "spherical" refers to a single lens whose surface shape is spherical, and its surface curvature determines the refraction path of light. Spherical lenses control the convergence or divergence of light rays through their radius of curvature and optical power (positive or negative). For example, a spherical lens with positive optical power can be used to converge light rays and compensate for the diverging effect of a spherical lens with negative optical power, while a spherical lens with negative optical power can be used to diverge light rays, adjust the optical path length, and correct aberrations.
[0088] Furthermore, the second spherical positive power lens 312 and the third spherical positive power lens 313 are both positive power lenses that are split from a single positive power lens, because split lenses are more effective at correcting aberrations.
[0089] The 3D-printed projection lens provided in this application uses a double concave spherical negative power lens as the object-side primary lens. Its double concave structure not only effectively expands the system's field of view but also significantly suppresses distortion, ensuring clear edge image quality. At the same time, its unique concave curvature design achieves two major breakthrough advantages: it not only significantly expands the system's field of view to an ultra-wide range of 120° but also precisely controls the distortion rate to below 0.1%. Moreover, the light divergence characteristics of the double concave spherical negative power lens provide optimized optical path control freedom for subsequent lenses, enabling the subsequent second and third spherical positive power lenses to achieve synergistic optical compensation. In addition, the two precisely matched spherical positive power lenses obtained from the lens split can form a converging dual engine, which not only completes the primary beam shaping but also delivers a uniform light field with a wavefront accuracy of λ / 4 to the middle group.
[0090] In some embodiments, reference Figure 3 As shown, in the 3D printing projection lens 300 provided in this application embodiment, the middle group 320 may include: along the optical path direction ( Figure 3 The fourth spherical negative power lens 321, the fifth spherical negative power lens 322, and the sixth spherical positive power lens 323 are arranged sequentially (in the direction of the OX arrows).
[0091] Furthermore, the refractive index Nd4 of the material of the fourth spherical negative power lens 321 is less than or equal to 1.65, and the Abbe number Vd4 of the material of the fourth spherical negative power lens 321 is greater than or equal to 60. Thus, the material of the fourth spherical negative power lens 321 has a low refractive index and a high Abbe number.
[0092] The refractive index Nd5 of the material of the fifth spherical negative power lens 322 is less than or equal to 1.65, and the Abbe number Vd5 of the material of the fifth spherical negative power lens 322 is greater than or equal to 60. Therefore, the material of the fifth spherical negative power lens 322 has a low refractive index and a high Abbe number.
[0093] The refractive index Nd6 of the material of the sixth spherical positive power lens 323 is greater than or equal to 1.65 and less than or equal to 1.75, and the Abbe number Vd6 of the material of the sixth spherical positive power lens 323 is greater than or equal to 50 and less than or equal to 60. Therefore, the material of the sixth spherical positive power lens 323 has a medium refractive index and a medium Abbe number.
[0094] Furthermore, the sixth spherical positive power lens 323 can be a biconvex spherical positive power lens.
[0095] Furthermore, there is a large air gap between the sixth spherical positive power lens 323 and the fourth spherical negative power lens 321 and the fifth spherical negative power lens 322.
[0096] The 3D printing projection lens provided in this application embodiment forms a double negative optical power lens by using a fourth spherical negative optical power lens and a fifth spherical negative optical power lens, which can further flatten the image plane. Then, the light enters a sixth spherical positive optical power lens. At this time, the sixth spherical positive optical power lens and the fourth and fifth spherical negative optical power lenses can produce opposite aberrations. Most of the opposite aberrations can cancel each other out. Moreover, there is a large air gap between the sixth spherical positive optical power lens and the fourth and fifth spherical negative optical power lenses, which can achieve large optical power separation and reduce the risk of introducing a large number of aperture aberrations. In addition, the surface light of the sixth spherical positive optical power lens is higher than that of the fourth and fifth spherical negative optical power lenses, thereby creating a local beam undulation, which can play a role in correcting field curvature.
[0097] In some embodiments, reference Figure 4 As shown, in the 3D printed projection lens 300 provided in this application embodiment, the rear group 330 may include: along the optical path direction ( Figure 4 The aperture 331, the seventh spherical positive power lens 332, the eighth spherical negative power lens 333, the ninth spherical positive power lens 334, the tenth spherical positive power lens 335, and the eleventh spherical positive power lens 336 are arranged sequentially (in the direction of the OX arrows).
[0098] Furthermore, the refractive index Nd7 of the material of the seventh spherical positive power lens 332 is less than or equal to 1.65, and the Abbe number Vd7 of the material of the seventh spherical positive power lens 332 is greater than or equal to 60. Thus, the material of the seventh spherical positive power lens 332 has a low refractive index and a high Abbe number.
[0099] The refractive index Nd8 of the material of the eighth spherical negative power lens 333 is greater than or equal to 1.65, and the Abbe number Vd8 of the material of the eighth spherical negative power lens 333 is less than or equal to 36. Therefore, the material of the eighth spherical negative power lens 333 has a low refractive index and a low Abbe number.
[0100] The refractive index Nd9 of the material of the ninth spherical positive power lens 334 is greater than or equal to 1.65 and less than or equal to 1.75, and the Abbe number Vd9 of the material of the ninth spherical positive power lens 334 is greater than or equal to 50 and less than or equal to 60. Therefore, the material of the ninth spherical positive power lens 334 has a medium refractive index and a medium Abbe number.
[0101] The refractive index Nd10 of the material of the tenth spherical positive power lens 335 is less than or equal to 1.65, and the Abbe number Vd10 of the material of the tenth spherical positive power lens 335 is greater than or equal to 60. Therefore, the material of the tenth spherical positive power lens 335 has a low refractive index and a high Abbe number.
[0102] The refractive index Nd11 of the material of the eleventh spherical positive power lens 336 is less than or equal to 1.65, and the Abbe number Vd11 of the material of the eleventh spherical positive power lens 336 is greater than or equal to 60. Therefore, the material of the eleventh spherical positive power lens 336 has a low refractive index and a high Abbe number.
[0103] The 3D printing projection lens provided in this application embodiment, by placing the aperture stop at the foremost position of the rear group, can effectively suppress edge field distortion rays and reduce higher-order aberrations. Simultaneously, a progressive power lens allocation scheme is adopted behind the aperture stop: a seventh spherical positive power lens serves as the first positive power lens, primarily used to correct axial chromatic aberration and control the principal ray to enter the image plane at a near-perpendicular angle; subsequently, an eighth spherical negative power lens is configured, whose negative power characteristics can actively adjust the image plane curvature and improve field curvature aberration; then, the... The nine-spherical positive power lens, the tenth-spherical positive power lens, and the eleventh-spherical positive power lens constitute a composite positive power group. The ninth-spherical positive power lens serves as a transition, and the tenth-spherical positive power lens and the eleventh-spherical positive power lens are derived through lens splitting technology. This design achieves three advantages: (1) It keeps the total optical power of the system positive, improving the uniformity of illumination at the edge field of view; (2) It reduces the light deflection angle step by step, significantly reducing spherical aberration and coma; (3) The multi-layer structure can provide additional degrees of freedom for chromatic aberration correction.
[0104] In some embodiments, in the 3D printing projection lens provided in this application, the focal length of the 3D printing lens is 24mm to 36mm; and / or, the focal length of the front group is 82mm to 124mm; and / or, the focal length of the middle group is -236mm to -157mm; and / or, the focal length of the rear group is 39mm to 58mm; and / or, the focal length of the first spherical negative power lens is -124mm to -82mm; and / or, the focal length of the second spherical positive power lens is 161mm to 241mm; and / or, the focal length of the third spherical positive power lens is 71mm to 107mm; and / or, the focal length of the fourth spherical negative power lens is... The focal lengths are: -95mm to -63mm; and / or, the focal length of the fifth spherical negative power lens is -51mm to -34mm; and / or, the focal length of the sixth spherical positive power lens is 52mm to 78mm; and / or, the focal length of the seventh spherical positive power lens is 62mm to 94mm; and / or, the focal length of the eighth spherical negative power lens is -52mm to -34mm; and / or, the focal length of the ninth spherical positive power lens is 68mm to 102mm; and / or, the focal length of the tenth spherical positive power lens is 71mm to 106mm; and / or, the focal length of the eleventh spherical positive power lens is 134mm to 202mm.
[0105] Specifically, the focal length of a 3D printed projection lens can be 24mm, 26mm, 28mm, 30mm, 33mm, or 36mm, etc.
[0106] The focal length of the front element can be 82mm, 85mm, 90mm, 100mm, 110mm, 100mm or 124mm, etc.
[0107] The focal length of the middle group can be -236mm, -200mm, -170mm or -157mm, etc.
[0108] The focal length of the rear element can be 39mm, 40mm, 44mm, 48mm, 50mm, or 58mm, etc.
[0109] The focal length of a first spherical negative power lens can be -124mm, -120mm, -110mm, -100mm, -80mm, or -82mm, etc.
[0110] The focal length of the second spherical positive power lens can be 161mm, 180mm, 200mm, 220mm or 241mm, etc.
[0111] The focal length of a third spherical positive power lens can be 71mm, 80mm, 90mm, 100mm, or 107mm, etc.
[0112] The focal length of the fourth spherical negative power lens can be -95mm, -85mm, -80mm, -75mm, -70mm or -63mm, etc.
[0113] The focal length of the fifth spherical negative power lens can be -51mm, -50mm, -45mm, -40mm, -38mm, or -34mm, etc.
[0114] The focal length of the sixth spherical positive power lens can be 52mm, 55mm, 60mm, 65mm, 70mm or 78mm, etc.
[0115] The focal length of the seventh spherical positive power lens can be 62mm, 70mm, 75mm, 80mm, 85mm or 94mm, etc.
[0116] The focal length of the eighth spherical negative power lens can be -52mm, -50mm, -45mm, -40mm, -36mm, or -34mm, etc.
[0117] Ninth-dimensional spherical positive power lenses are available in 68mm, 70mm, 80mm, 90mm, 100mm, or 102mm.
[0118] Tenth-power spherical positive optical lenses are available in 71mm, 80mm, 85mm, 90mm, 100mm, or 106mm.
[0119] The eleventh spherical positive focal length lens has a focal length of 134mm, 150mm, 170mm, 190mm, 200mm, or 202mm, etc.
[0120] The 3D printing projection lens provided in this application embodiment first uses a negative power lens to expand the field of view and suppress distortion in the front group. Then, two positive power lenses initially converge the light to provide a uniform beam for the subsequent middle group. The middle group then uses two double negative power lenses to further flatten the image plane. Subsequently, a positive power lens compensates for edge astigmatism, and the surface light of this positive power lens is higher than that of the two negative power lenses, creating local beam undulations, which has the function of correcting field curvature. It also completes the shaping of light speed in front of the aperture, so that the light transitions smoothly to the rear group. In the rear group, the aperture and a positive power lens first control the main light to be perpendicular to the image plane. Then, a negative power lens adjusts the curvature of the image plane, improving telecentrism and resolution. Finally, three positive power lenses eliminate secondary spectrum, correct chromatic aberration, and achieve edge MTF optimization.
[0121] The following provides identification information for the optical elements or specific locations of the 3D-printed projection lens in this embodiment, including surface, type, radius of curvature, thickness, and glass type, thereby obtaining a specific 3D-printed projection lens. The actual configuration of this 3D-printed projection lens is shown in Table 1 below.
[0122] It should be noted that the object surface in Table 1 generally refers to the plane that provides the "raw image / light signal" to be projected, which is the "input end" of the 3D printing projection lens. It should be noted that the object surface in Table 1 is... Figure 7 Surface 1 in the middle.
[0123] The image plane generally refers to the "final imaging plane" formed after the object's image is projected through a 3D printing projection lens. Specifically, it can be the upper surface of liquid resin (where the resin receives light signals and solidifies).
[0124] Each individual lens, aperture, object plane, and image plane is a spherical surface, and its surface curvature determines the refraction path of light.
[0125] Thickness refers to the thickness of a single optical element or the thickness of the air, measured in mm.
[0126] Figure 5 The diagram shows the specific optical surface numbers of the 3D printed projection lens in this embodiment, numbered S1-S12, S14-23 according to the optical path direction (from O to X). Each optical surface facing O is designated as the left surface, and each optical surface facing X is designated as the right surface.
[0127] Table 1
[0128]
[0129]
[0130] Figure 6 This is a schematic diagram of the light path of a 3D printed projection lens with the parameters in Table 1.
[0131] Figure 7 This is a schematic diagram of a real-world scenario using a 3D-printed projection lens with the parameters listed in Table 1.
[0132] It should be noted that, Figure 6 and Figure 7 The different colors in the image represent different beams of light in the field of view.
[0133] This application provides a 3D printed projection lens. The front group uses a biconcave negative power lens and a bipositive power lens to jointly correct field aberrations, which are mainly caused by distortion. Specifically, the lens closest to the projection surface in the front group uses a negative power lens to expand the field of view, suppress distortion, and extend the back intercept. This allows the system to maintain a longer effective focal length while compressing the overall length of the lens and making the edge field magnification more uniform. Moreover, the negative power lens can diverge light, providing more space for the positive power lens to adjust the image plane. The two positive power lenses initially converge the light, providing uniform light for the subsequent middle group.
[0134] The middle group uses a combination of double negative power lenses and double convex positive power lenses to correct field curvature and astigmatism. Specifically, a fine balance is achieved through the "overcorrection" of the double negative power lenses and the "reversal" of the positive power lenses. The double negative power lenses correct field curvature while further flattening the image plane, thereby correcting astigmatism. The positive power lenses reconverge the divergent light rays emitted by the negative power lenses and can also form an achromatic unit with the lenses. Field curvature correction is achieved through the undulation of light rays on the surfaces of the positive and negative power lenses. However, because this method introduces a large amount of aperture aberration, a large air gap is required to separate the positive and negative power.
[0135] The rear group first adjusts the light through the aperture stop, then uses positive power lenses to control the principal ray to be perpendicular to the image plane, and negative power lenses to adjust the curvature of the image plane, improving telecentrism and resolution. In this way, multiple positive power lenses can eliminate second-order spectral distortion, correct chromatic aberration, and optimize edge MTF. Therefore, through the synergistic effect of aperture stop division and multiple power lenses, aperture aberrations can be optimized. Furthermore, the lens splitting method reduces the pressure on the positive power lenses to correct spherical aberration, thus reducing the risk of higher-order aberrations and compressing space, reducing the use of single lenses. Specifically, the rear group uses three positive power lenses to handle the optical power, ensuring transmittance in the ultraviolet (UV) band, primarily serving to maintain telecentrism, correct spherical aberration, and ensure smooth light transitions.
[0136] Therefore, the 3D printed projection lens in this embodiment achieves effects such as small F#, high brightness, and good imaging.
[0137] In some embodiments, the 3D printed projection lens provided in this application is composed of 12 single lenses arranged in a single lens array; and / or, the 3D printed projection lens is used to operate in the optical wavelength range of 370nm to 440nm; and / or, the aperture number (F#) of the 3D printed projection lens is 1.7 to 1.9; and / or, the working distance of the 3D printed projection lens is 200mm to 1000mm; and / or, the 3D printed projection lens is suitable for a 0.78-inch DMD.
[0138] Specifically, 3D printed projection lenses can be used to work in optical wavelengths such as 370nm, 390nm, 410nm, or 440nm.
[0139] The F# of a 3D printed projection lens can be 1.8, 1.85, or 1.9, etc.
[0140] The working distance of a 3D printing projection lens can be 200mm, 400mm, 600mm, 800mm, or 1000mm, etc.
[0141] The 3D printed projection lens provided in this application embodiment can achieve effects such as small F#, high brightness and good imaging by setting the working band, working distance, F# and DMD size of the 3D printed projection lens.
[0142] Figure 8 A schematic diagram of the modulation transfer function (MTF) at a display chip (e.g., DMD) is shown. It should be noted that MTF is an important indicator for evaluating the ability of an optical system to transmit signals at different spatial frequencies. It represents the overall resolving power of the optical system and reflects its ability to reproduce object details; a value closer to 1 indicates better transmission performance.
[0143] The MTF diagram represents the overall resolving power of an optical system. Figure 8 The horizontal axis represents spatial frequency in cycles per millimeter (mm), and the vertical axis represents the optical transfer function (OTF) modulus (i.e., the MTF value). The OTF modulus is used to evaluate the imaging quality of 3D printed projection lenses, with a value ranging from 0 to 1. A higher and straighter MTF curve indicates better imaging quality, stronger ability to reproduce realistic images, better overlap of curves across different fields of view, and better image quality consistency. Figure 8 In the mean, the MTF observation line pairs are 56 lp / mm.
[0144] from Figure 8 It can be clearly seen that in the visible light band (usually in the range of 380nm to 760nm), when the spatial frequency is 56lp / mm, the MTF of the entire field of view is greater than or equal to 0.4, the imaging quality is good, and it can meet the actual use requirements.
[0145] Example 2
[0146] This application provides a 3D printed projection optical engine, which may include at least one 3D printed projection lens as described in Embodiment 1, arranged sequentially from the object side to the image side along the optical path direction.
[0147] Further reference Figure 1 As shown, the 3D printing projection optical engine in this embodiment may further include: along the optical path direction from the image side to the object side (i.e., from... Figure 1 The display chip 301, display chip protective glass 302, galvanometer 303 and prism equivalent plate 304 are arranged sequentially in the X to O direction.
[0148] In practical applications, the display chip can be a DMD, etc., depending on the actual needs.
[0149] The 3D printing projection optical engine provided in this application embodiment uses an eleventh spherical positive power lens in the 3D printing projection lens as the rear terminal lens. Located closest to the prism equivalent plate, it can bear the main positive power, ensuring the formation of a high-quality converging real image on the DMD imaging surface. At the same time, as the final optical interface, it can match the optical characteristics of the prism equivalent plate, reducing interface reflection loss. In conjunction with the multiple single lenses in front, it achieves aberration balance of the entire optical system. As a result, the 3D printing projection optical engine has high imaging quality and low cost, which is beneficial for industrial production and application.
[0150] This section only introduces the content related to the invention point; other information can be obtained by referring to relevant technologies, and will not be explained in detail here.
[0151] The above are merely preferred embodiments of this application and are not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.
Claims
1. A 3D-printed projection lens, characterized in that, include: The front group, middle group, and rear group are arranged sequentially from the object side to the image side along the optical path direction. The front group and the middle group are separate and spaced apart, and the middle group and the rear group are separate and spaced apart. Along the optical path direction, the front group includes at least one negative power lens and two positive power lenses; The middle group includes at least two negative power lenses and one positive power lens; The rear group includes at least one set of combined optical power lenses arranged in a positive-negative-positive configuration, and two positive optical power lenses.
2. The 3D printed projection lens according to claim 1, characterized in that, The negative power lens in the front group is biconcave in shape; And / or, the positive power lens in the middle group is biconvex in shape.
3. The 3D printed projection lens according to claim 1 or 2, characterized in that, The front group consists of a first negative power lens, a second positive power lens, and a third positive power lens arranged sequentially along the optical path direction. The refractive index of the material of the first negative power lens is less than or equal to 1.65, and the Abbe number of the material of the first negative power lens is less than or equal to 36. And / or, the refractive index of the material of the second positive focal length lens is greater than or equal to 1.8, and the Abbe number of the material of the second positive focal length lens is less than or equal to 40; And / or, the refractive index of the material of the third positive power lens is less than or equal to 1.65, and the Abbe number of the material of the third positive power lens is greater than or equal to 60.
4. The 3D printed projection lens according to claim 1 or 2, characterized in that, The middle group consists of a fourth negative power lens, a fifth negative power lens, and a sixth positive power lens arranged sequentially along the optical path. The refractive index of the material of the fourth negative power lens is less than or equal to 1.65, and the Abbe number of the material of the fourth negative power lens is greater than or equal to 60. And / or, the refractive index of the material of the fifth negative power lens is less than or equal to 1.65, and the Abbe number of the material of the fifth negative power lens is greater than or equal to 60; And / or, the refractive index of the material of the sixth positive focal power lens is greater than or equal to 1.65 and less than or equal to 1.75, and the Abbe number of the material of the sixth positive focal power lens is greater than or equal to 50 and less than or equal to 60.
5. The 3D printed projection lens according to claim 1 or 2, characterized in that, The rear group includes an aperture stop, a seventh positive power lens, an eighth negative power lens, a ninth positive power lens, a tenth positive power lens, and an eleventh positive power lens arranged sequentially along the optical path direction. The refractive index of the material of the seventh spherical positive power lens is less than or equal to 1.65, and the Abbe number of the material of the seventh spherical positive power lens is greater than or equal to 60. And / or, the refractive index of the material of the eighth negative power lens is greater than or equal to 1.65, and the Abbe number of the material of the eighth negative power lens is less than or equal to 36; And / or, the refractive index of the material of the ninth positive focal power lens is greater than or equal to 1.65 and less than or equal to 1.75, and the Abbe number of the material of the ninth positive focal power lens is greater than or equal to 50 and less than or equal to 60; And / or, the refractive index of the material of the tenth positive power lens is less than or equal to 1.65, and the Abbe number of the material of the tenth positive power lens is greater than or equal to 60; And / or, the refractive index of the material of the eleventh positive power lens is less than or equal to 1.65, and the Abbe number of the material of the eleventh positive power lens is greater than or equal to 60.
6. The 3D printed projection lens according to claim 1 or 2, characterized in that, The front group consists of a first spherical negative power lens, a second spherical positive power lens, and a third spherical positive power lens arranged sequentially from the object side to the image side along the optical path direction. The middle group consists of a fourth spherical negative power lens, a fifth spherical negative power lens, and a sixth spherical positive power lens arranged sequentially from the object side to the image side along the optical path direction. The rear group consists of an aperture stop, a seventh spherical positive power lens, an eighth spherical negative power lens, a ninth spherical positive power lens, a tenth spherical positive power lens, and an eleventh spherical positive power lens arranged sequentially from the object side to the image side along the optical path direction.
7. The 3D printed projection lens according to claim 6, characterized in that, The focal length of the 3D printed projection lens is 24mm to 36mm; And / or, the focal length of the front group is 82mm to 124mm; And / or, the focal length of the middle group is -236.2368mm to -157mm; And / or, the focal length of the rear group is 39mm to 58mm; And / or, the focal length of the first spherical negative power lens is -124mm to -82mm; And / or, the focal length of the second spherical positive power lens is 161mm to 241mm; And / or, the focal length of the third spherical positive power lens is 71mm to 107mm; And / or, the focal length of the fourth spherical negative power lens is -95mm to -63mm; And / or, the focal length of the fifth spherical negative power lens is -51mm to -34mm; And / or, the focal length of the sixth spherical positive power lens is 52mm to 78mm; And / or, the focal length of the seventh spherical positive power lens is 62mm to 94mm; And / or, the focal length of the eighth spherical negative power lens is -52mm to -34mm; And / or, the focal length of the ninth spherical positive power lens is 68mm to 102mm; And / or, the focal length of the tenth spherical positive power lens is 71mm to 106mm; And / or, the focal length of the eleventh spherical positive power lens is 134mm to 202mm.
8. The 3D printed projection lens according to claim 1 or 2, characterized in that, The 3D printed projection lens is composed of 12 single lenses arranged in a single lens; And / or, the 3D-printed projection lens is used to operate in the optical wavelength range of 370nm to 440nm; And / or, the aperture number of the 3D printed projection lens is 1.7 to 1.9; And / or, the working distance of the 3D printing projection lens is 200mm to 1000mm.
9. A 3D printing projection light engine, characterized in that, Includes a 3D printed projection lens as described in any one of claims 1 to 8.
10. The 3D printing projection optical engine according to claim 9, characterized in that, The 3D printing projection optical engine also includes: a display chip, a display chip protective glass, a galvanometer, and a prism equivalent plate. The display chip, the display chip protective glass, the galvanometer, and the prism equivalent plate are arranged sequentially from the image side to the object side along the optical path direction.