Miniaturized projection lens and imaging device
By miniaturizing the design and using aspherical lenses, and optimizing optical parameters, the problem of excessively large projection lenses has been solved, enabling use in confined spaces and high-brightness imaging.
Patent Information
- Application Number
- CN202511972343.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-25
- Publication Date
- 2026-03-03
AI Technical Summary
Existing projection lenses are usually too large to be used in confined spaces, which limits their application scenarios.
It adopts a miniaturized design and uses five aspherical lenses to meet specific optical parameters and structural conditions, including field of view, total optical length, lens spacing and lens Abbe number, and optimizes the optical path design to reduce size and improve brightness.
This technology enables the miniaturization of projection lenses, expands their application range, reduces the number of lenses, and improves image quality and brightness.
Smart Images
Figure CN121596512A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of optics, specifically to a miniaturized projection lens and imaging device. Background Technology
[0002] A projection lens, also known as a projector lens, is the core optical component of a projector. Based on projection distance, they are categorized into short-throw, medium-throw, long-throw, and special types such as reflective and fisheye lenses. They are widely used in education, engineering, and home applications. The core parameter is the throw ratio, which is the ratio of projection distance to screen width. Short-throw lenses have a throw ratio of less than 1, while ultra-short-throw lenses can reach 0.25, enabling the projection of large images from short distances.
[0003] Currently, existing projection lenses are typically used in conference settings. To increase the transmittance of the projection lens, a large number of lenses are used, resulting in an excessively large size of the projection lens. For some small indoor conferences, the above-mentioned projection lenses are still too large, and their application scenarios are relatively limited. Summary of the Invention
[0004] This invention addresses existing technical problems by providing a miniaturized projection lens and imaging device. Through the setting of the above parameters and structure, the projection lens is miniaturized, making it easier to use in confined spaces and increasing the application range of the miniaturized projection lens.
[0005] The technical solution provided by this invention is as follows:
[0006] A miniaturized projection lens, wherein the miniaturized projection lens comprises, from the object side to the image side, a first lens with negative optical power, a second lens with negative optical power, a third lens with positive optical power, an aperture, a fourth lens with positive optical power, a fifth lens with positive optical power, a sixth lens with negative optical power, and a seventh lens with positive optical power.
[0007] The miniaturized projection lens satisfies the following condition:
[0008] 1mm < f < 2mm;
[0009] TTL < 12mm;
[0010] Where f is the field of view of the miniaturized projection lens, and TTL is the total optical length of the miniaturized projection lens.
[0011] By setting the above parameters and structure, the projection lens is miniaturized, making it easier to use in confined spaces and increasing the application range of the miniaturized projection lens.
[0012] Preferably, the miniaturized projection lens comprises at least five aspherical lenses.
[0013] In this technical solution, the number of lenses used in the miniaturized projection lens is reduced by using a large number of aspherical lenses, thus reducing the size of the miniaturized projection lens and achieving miniaturization of the projection lens.
[0014] Preferably, the miniaturized projection lens satisfies the following condition:
[0015] HFOV > 80°;
[0016] HFOV is the half field of view of the miniaturized projection lens.
[0017] Preferably, the third lens satisfies the following condition:
[0018] Vd3 < 25;
[0019] Wherein, Vd3 is the Abbe number of the third lens.
[0020] In this technical solution, by limiting the Abbe number of the third lens, the thickness of the third lens is reduced, while the optical path is optimized, the dissipation of light received by the aperture is reduced, and the brightness of the miniaturized projection lens is increased.
[0021] Preferably, the miniaturized projection lens satisfies the following condition:
[0022] 0.5 < R52 / R61 < 2;
[0023] Wherein, R52 is the radius of curvature of the fifth lens near the image plane, and R61 is the radius of curvature of the sixth lens near the object plane.
[0024] In this technical solution, by limiting the curvature radii of the fifth and sixth lenses, the light dissipation between the fifth and sixth lenses is further reduced, thereby increasing the brightness of the miniaturized lens.
[0025] Preferably, the sixth lens satisfies the following condition:
[0026] Vd6 < 25;
[0027] Wherein, Vd6 is the Abbe number of the sixth lens.
[0028] In this technical solution, the optical path of the miniaturized projection lens is optimized by limiting the Abbe number of the sixth lens, thereby increasing the imaging quality of the miniaturized projection lens.
[0029] Preferably, the first lens satisfies the following condition:
[0030] Nd1 > 1.75;
[0031] Nd1 is the refractive index of the first lens.
[0032] In this technical solution, by limiting the refractive index of the first lens, the angle of light that the miniaturized projection lens can receive is greatly increased, thus achieving the effect of a large aperture in the miniaturized projection lens.
[0033] Preferably, the miniaturized projection lens satisfies the following condition:
[0034] Φ1 / TTL>0.9;
[0035] Wherein, Φ1 is the outer diameter of the first lens.
[0036] In this technical solution, by limiting the outer diameter of the first lens, the range of light that the first lens can receive is increased, thereby further increasing the brightness of the image formed by the miniaturized projection lens.
[0037] Preferably, the miniaturized projection lens satisfies the following condition:
[0038] D47 / T47 < 0.15;
[0039] Wherein, D47 is the sum of the gaps between the fourth lens and the seventh lens, and T47 is the total optical length of the fourth lens and the seventh lens.
[0040] In this technical solution, by limiting the above parameters, the gap between the fourth and seventh lenses is greatly reduced, thereby achieving miniaturization of the miniaturized projection lens, reducing light dissipation between the fourth and seventh lenses, and increasing the imaging quality of the miniaturized projection lens.
[0041] One of the objectives of this invention is to provide an imaging device, comprising: a miniaturized projection lens;
[0042] An imaging element is configured to receive an image formed by the miniaturized projection lens.
[0043] Compared with the prior art, the miniaturized projection lens and imaging device provided by the present invention have the following beneficial effects:
[0044] 1. By setting the above parameters and structure, the projection lens is miniaturized, making it easier to use in confined spaces and increasing the application range of the miniaturized projection lens.
[0045] 2. By using a large number of aspherical lenses, the number of lenses used in the miniaturized projection lens is reduced, the size of the miniaturized projection lens is reduced, and the miniaturization of the projection lens is achieved.
[0046] 3. The gap between the fourth and seventh lenses has been greatly reduced, enabling miniaturization of the projection lens, reducing light dissipation between the fourth and seventh lenses, and increasing the imaging quality of the miniaturized projection lens. Attached Figure Description
[0047] The preferred embodiments will now be described in a clear and easy-to-understand manner, with reference to the accompanying drawings, to further explain the above-mentioned characteristics, technical features, advantages, and implementation methods of a miniaturized projection lens and imaging device.
[0048] Figure 1 This is a schematic diagram of the structure of a miniaturized projection lens according to the present invention;
[0049] Figure 2 This is an aberration diagram of a miniaturized projection lens according to the present invention;
[0050] Figure 3 This is a coma diagram of a miniaturized projection lens according to the present invention.
[0051] Figure 4 This is a schematic diagram of another miniaturized projection lens according to the present invention;
[0052] Figure 5 This is an aberration diagram of another miniaturized projection lens of the present invention;
[0053] Figure 6 This is a coma diagram of another miniaturized projection lens of the present invention.
[0054] Explanation of the reference numerals: L1, first lens; L2, second lens; L3, third lens; L4, fourth lens; L5, fifth lens; L6, sixth lens; L7, seventh lens; STO, aperture stop; CG1, first protective glass; CG2, second protective glass. Detailed Implementation
[0055] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0056] To keep the drawings concise, each figure only schematically shows the parts relevant to the invention, and these do not represent the actual structure of the product. Furthermore, to facilitate understanding, in some figures, only one of components with the same structure or function is schematically depicted, or only one is labeled. In this document, "one" not only means "only one," but can also mean "more than one."
[0057] Example 1
[0058] like Figure 1 and Figure 4 As shown, a miniaturized projection lens is composed of a first lens L1 with negative optical power, a second lens L2 with negative optical power, a third lens L3 with positive optical power, an aperture stop STO, a fourth lens L4 with positive optical power, a fifth lens L5 with positive optical power, a sixth lens L6 with negative optical power, and a seventh lens L7 with positive optical power, arranged sequentially from the object plane side to the image plane side.
[0059] The miniaturized projection lens satisfies the following condition:
[0060] 1mm < f < 2mm;
[0061] TTL < 12mm;
[0062] Where f is the field of view of the miniaturized projection lens, and TTL is the total optical length of the miniaturized projection lens.
[0063] By setting the above parameters and structure, the projection lens is miniaturized, making it easier to use in confined spaces and increasing the application range of the miniaturized projection lens.
[0064] The miniaturized projection lens contains at least five aspherical lenses.
[0065] By using a large number of aspherical lenses, the number of lenses used in the miniaturized projection lens is reduced, the size of the miniaturized projection lens is reduced, and miniaturization of the projection lens is achieved.
[0066] The miniaturized projection lens satisfies the following condition:
[0067] HFOV > 80°;
[0068] HFOV is the half field of view of the miniaturized projection lens.
[0069] The third lens L3 satisfies the following condition:
[0070] Vd3 < 25;
[0071] Wherein, Vd3 is the Abbe number of the third lens L3.
[0072] In this embodiment, by limiting the Abbe number of the third lens L3, the thickness of the third lens L3 is reduced, while the optical path is optimized, the dissipation of light received by the aperture STO is reduced, and the brightness of the miniaturized projection lens is increased.
[0073] The miniaturized projection lens satisfies the following condition:
[0074] 0.5 < R52 / R61 < 2;
[0075] Wherein, R52 is the radius of curvature of the fifth lens L5 near the image plane side surface, and R61 is the radius of curvature of the sixth lens L6 near the object plane side surface.
[0076] By limiting the curvature radii of the fifth lens L5 and the sixth lens L6, the light dissipation between the fifth lens L5 and the sixth lens L6 is further reduced, increasing the brightness of the miniaturized lens.
[0077] The sixth lens L6 satisfies the following condition:
[0078] Vd6 < 25;
[0079] Wherein, Vd6 is the Abbe number of the sixth lens L6.
[0080] By limiting the Abbe number of the sixth lens (L6), the optical path of the miniaturized projection lens is optimized, thereby increasing the imaging quality of the miniaturized projection lens.
[0081] The first lens L1 satisfies the following condition:
[0082] Nd1 > 1.75;
[0083] Nd1 is the refractive index of the first lens L1.
[0084] By limiting the refractive index of the first lens L1, the angle of light that the miniaturized projection lens can receive is greatly increased, thus achieving the effect of a large aperture in the miniaturized projection lens.
[0085] The miniaturized projection lens satisfies the following condition:
[0086] Φ1 / TTL>0.9;
[0087] Wherein, Φ1 is the outer diameter of the first lens L1.
[0088] By limiting the outer diameter of the first lens L1, the range of light that the first lens L1 can receive is increased, further increasing the brightness of the image formed by the miniaturized projection lens.
[0089] The miniaturized projection lens satisfies the following condition:
[0090] D47 / T47 < 0.15;
[0091] Wherein, D47 is the sum of the gaps between the fourth lens L4 and the seventh lens L7, and T47 is the total optical length of the fourth lens L4 to the seventh lens L7.
[0092] By limiting the parameters mentioned above, the gap between the fourth lens L4 and the seventh lens L7 is greatly reduced, achieving miniaturization of the projection lens, reducing light dissipation between the fourth lens L4 and the seventh lens L7, and increasing the imaging quality of the miniaturized projection lens.
[0093] Example 2
[0094] like Figures 1 to 3 As shown, a miniaturized projection lens is composed of, from the object plane side to the image plane side, a first lens L1 with negative optical power, a second lens L2 with negative optical power, a third lens L3 with positive optical power, an aperture STO, a fourth lens L4 with positive optical power, a fifth lens L5 with positive optical power, a sixth lens L6 with negative optical power, a seventh lens L7 with positive optical power, a first protective glass CG1, and a second protective glass CG2.
[0095] The basic lens data of the miniaturized projection lens in this embodiment is shown in Table 1, and the aspherical coefficients are shown in Table 2.
[0096] The surface number column shows the surface number when the object-side surface is set as surface 1 and the numbering is increased sequentially towards the image side; the surface type column shows the surface type of a lens; the radius of curvature column shows the radius of curvature of a lens, where a positive radius of curvature indicates that the surface is curved towards the object side and a negative radius of curvature indicates that the surface is curved towards the image side; the center thickness column shows the surface spacing on the optical axis between each surface and the surface adjacent to it on the image side; the refractive index column shows the refractive index of a lens; and the Abbe number column shows the Abbe number of a lens.
[0097] In Table 2, K is the conic coefficient, and e is the scientific notation, for example, e-05 represents 10. -5 .
[0098] Table 1
[0099] Face number Surface type radius of curvature / mm Center thickness / mm Refractive index Abbe number OBJ S1 spherical 9.343 1.2 1.80 46.5 S2 spherical 2.676 1.134 S3 aspherical 1.232 0.478 1.54 55.65 S4 aspherical 0.605 0.728 S5 aspherical 2.426 1.073 1.66 20.38 S6 aspherical 3.32 0.575 STO spherical INF 0.139 S8 spherical 15.916 1.021 1.62 60.36 S9 spherical -1.681 0.179 S10 aspherical 6.674 1.031 1.54 55.65 S11 aspherical -3.053 0.077 S12 aspherical -2.093 0.45 1.66 20.38 S13 aspherical 4.33 0.192 S14 aspherical 1.811 1.497 1.54 55.65 S15 aspherical -1.991 0.19 S16 spherical INF 0.21 1.52 64.14 S17 spherical INF 0.5 S18 spherical INF 0.4 1.52 64.14 S19 spherical INF 0.2 IMG
[0100] Table 2
[0101]
[0102]
[0103] In this embodiment, f = 1.12 mm, fno = 1.77, TTL = 11.274 mm, and HFOV = 85.5°;
[0104] Where f is the focal length of the miniaturized projection lens, fno is the aperture number of the miniaturized projection lens, HFOV is the half field of view of the miniaturized projection lens, and TTL is the total optical length of the miniaturized projection lens.
[0105] Vd3 = 20.38; Vd6 = 20.38;
[0106] Wherein, Vd3 is the Abbe number of the third lens L3, and Vd6 is the Abbe number of the sixth lens L6.
[0107] Nd1 = 1.8;
[0108] Wherein, Nd1 is the refractive index of the first lens L1.
[0109] R52=-3.053mm, R61=-2.093mm;
[0110] R52 / R61 = 1.46;
[0111] R52 is the radius of curvature of the fifth lens L5 near the image plane, and R61 is the radius of curvature of the sixth lens L6 near the object plane.
[0112] Φ1=10.72mm, Φ1 / TTL=0.95;
[0113] Wherein, Φ1 is the outer diameter of the first lens L1.
[0114] D47=0.448mm, T47=4.447mm;
[0115] D47 / T47 = 0.101;
[0116] Wherein, D47 is the sum of the gaps between the fourth lens L4 and the seventh lens L7, and T47 is the total optical length of the fourth lens L4 to the seventh lens L7.
[0117] Example 3
[0118] like Figures 4 to 6 As shown, a miniaturized projection lens is composed of, from the object plane side to the image plane side, a first lens L1 with negative optical power, a second lens L2 with negative optical power, a third lens L3 with positive optical power, an aperture STO, a fourth lens L4 with positive optical power, a fifth lens L5 with positive optical power, a sixth lens L6 with negative optical power, a seventh lens L7 with positive optical power, a first protective glass CG1, and a second protective glass CG2.
[0119] The basic lens data of the miniaturized projection lens in this embodiment is shown in Table 3, and the aspherical coefficients are shown in Table 4.
[0120] The surface number column shows the surface number when the object-side surface is set as surface 1 and the numbering is increased sequentially towards the image side; the surface type column shows the surface type of a lens; the radius of curvature column shows the radius of curvature of a lens, where a positive radius of curvature indicates that the surface is curved towards the object side and a negative radius of curvature indicates that the surface is curved towards the image side; the center thickness column shows the surface spacing on the optical axis between each surface and the surface adjacent to it on the image side; the refractive index column shows the refractive index of a lens; and the Abbe number column shows the Abbe number of a lens.
[0121] In Table 4, K is the conic coefficient, and e is the scientific notation, for example, e-05 represents 10. -5 .
[0122] Table 3
[0123]
[0124]
[0125] Table 4
[0126]
[0127] In this embodiment, f = 1.29 mm, fno = 1.82, TTL = 10.93 mm, and HFOV = 85.5°;
[0128] Where f is the focal length of the miniaturized projection lens, fno is the aperture number of the miniaturized projection lens, HFOV is the half field of view of the miniaturized projection lens, and TTL is the total optical length of the miniaturized projection lens.
[0129] Vd3 = 20.38; Vd6 = 20.38;
[0130] Wherein, Vd3 is the Abbe number of the third lens L3, and Vd6 is the Abbe number of the sixth lens L6.
[0131] Nd1 = 1.8;
[0132] Wherein, Nd1 is the refractive index of the first lens L1.
[0133] R52=-2.307mm, R61=-1.735mm;
[0134] R52 / R61 = 1.33;
[0135] R52 is the radius of curvature of the fifth lens L5 near the image plane, and R61 is the radius of curvature of the sixth lens L6 near the object plane.
[0136] Φ1=10.69mm, Φ1 / TTL=0.98;
[0137] Wherein, Φ1 is the outer diameter of the first lens L1.
[0138] D47=0.328mm, T47=4.332mm;
[0139] D47 / T47 = 0.076;
[0140] Wherein, D47 is the sum of the gaps between the fourth lens L4 and the seventh lens L7, and T47 is the total optical length of the fourth lens L4 to the seventh lens L7.
[0141] Example 4
[0142] An imaging device, such as Figures 1 to 6 As shown, it includes: a miniaturized projection lens as described in any of the above embodiments, and an imaging element configured to receive an image formed by the miniaturized projection lens.
[0143] It should be noted that the above embodiments can be freely combined as needed. The above description is only a preferred embodiment of the present invention. It should be pointed out that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.
Claims
1. A miniaturized projection lens, characterized in that, The miniaturized projection lens consists of a first lens with negative optical power, a second lens with negative optical power, a third lens with positive optical power, an aperture, a fourth lens with positive optical power, a fifth lens with positive optical power, a sixth lens with negative optical power, and a seventh lens with positive optical power, arranged sequentially from the object plane side to the image plane side. The miniaturized projection lens satisfies the following condition: 1mm < f < 2mm; TTL < 12mm; Where f is the field of view of the miniaturized projection lens, and TTL is the total optical length of the miniaturized projection lens.
2. The miniaturized projection lens according to claim 1, characterized in that: The miniaturized projection lens contains at least five aspherical lenses.
3. A miniaturized projection lens according to claim 1, characterized in that: The miniaturized projection lens satisfies the following condition: HFOV > 80°; HFOV is the half field of view of the miniaturized projection lens.
4. A miniaturized projection lens according to claim 1, characterized in that: The third lens satisfies the following condition: Vd3 < 25; Wherein, Vd3 is the Abbe number of the third lens.
5. A miniaturized projection lens according to claim 1, characterized in that: The miniaturized projection lens satisfies the following condition: 0.5 < R52 / R61 < 2; Wherein, R52 is the radius of curvature of the fifth lens near the image plane, and R61 is the radius of curvature of the sixth lens near the object plane.
6. A miniaturized projection lens according to claim 1, characterized in that: The sixth lens satisfies the following condition: Vd6 < 25; Wherein, Vd6 is the Abbe number of the sixth lens.
7. A miniaturized projection lens according to claim 1, characterized in that: The first lens satisfies the following condition: Nd1 > 1.75; Nd1 is the refractive index of the first lens.
8. A miniaturized projection lens according to claim 1, characterized in that: The miniaturized projection lens satisfies the following condition: Φ1 / TTL>0.9; Wherein, Φ1 is the outer diameter of the first lens.
9. A miniaturized projection lens according to claim 1, characterized in that: The miniaturized projection lens satisfies the following condition: D47 / T47 < 0.15; Wherein, D47 is the sum of the gaps between the fourth lens and the seventh lens, and T47 is the total optical length of the fourth lens and the seventh lens.
10. An imaging device, characterized in that, include: The miniaturized projection lens as described in any one of claims 1 to 9; An imaging element is configured to receive an image formed by the miniaturized projection lens.