High-brightness low-cost DMD welcome lamp lens

Abstract

The utility model relates to a high-brightness low-cost DMD welcome lamp lens. An optical system of the lens is composed of a first lens, a second lens, a third lens, a diaphragm, a fourth lens and a fifth lens which are sequentially arranged from left to right along a light incident light path. The lenses are made of plastic and glass materials, the first lens, the second lens, the third lens and the fourth lens are plastic aspheric lenses, and the fifth lens is a glass spherical lens. By reasonably distributing the focal power and the surface type of each lens, the central thickness of each lens, the axial distance between the lenses and the like, the imaging performance requirement of the lens is met, the total length of the lens and the radial size of each lens are reduced, and the miniaturization of the lens group is realized.

Description

Technical Field

[0001] The utility model relates to the technical field of lenses, in particular to a high-brightness and low-cost DMD welcome light lens. Background Art

[0002] The in-vehicle projection loqo lighting system generally consists of three parts: lighting system, film pattern (or transparent display screen to achieve dynamic pattern) and imaging projection. It is generally a transplantation application of conventional consumer projection system. There are many in-vehicle projection solutions at present, including MLA solution based on semiconductor etching process, traditional film solution (plastic or glass), transparent display screen (dynamic pattern can be achieved), and DLP and LCOS-based solutions (such solutions are relatively expensive and need to consider automotive-grade chips and LEDs. They are suitable for high-end models and will become more popular after the cost and corresponding automotive-grade standards are met). GAC Passenger Cars first used the exterior rearview mirror welcome light solution, which was favored by customers after application and greatly improved the user experience. However, as users become younger and younger, the market is increasingly dissatisfied with solutions that can only project a single LOGO, and expects a mature DMD solution that can project different patterns or even dynamic videos. Its brightness and cost are the main constraints of this solution. Utility Model Content

[0003] In view of the deficiencies in the prior art, the technical problem to be solved by the utility model is to provide a high-brightness and low-cost DMD welcome light lens, which not only has a large light aperture and low tolerance sensitivity, but also has good high and low temperature stability.

[0004] In order to solve the above technical problems, the technical solution of the utility model is: a high-brightness and low-cost DMD welcome light lens, the optical system of the lens is composed of a first lens, a second lens, a third lens, an aperture, a fourth lens and a fifth lens arranged in sequence from left to right along the incident light path of the light; without considering the backcurvature caused by the aspheric coefficient, the first lens is a double concave negative lens, the object side surface of which is concave, and the image side surface is concave; the second lens is a meniscus concave negative lens, the object side surface of which is convex, and the image side surface is concave; the third lens is a double convex positive lens, the object side surface of which is convex, and the image side surface is convex; the fourth lens is a meniscus convex positive lens, the object side surface of which is concave, and the image side surface is convex; the fifth lens is a double convex positive lens, the object side surface of which is convex, and the image side surface is convex; the lenses are made of plastic and glass materials, the first lens, the second lens, the third lens, and the fourth lens are plastic aspheric lenses, and the fifth lens is a glass spherical lens.

[0005] Preferably, the focal length of the optical system is f, and the focal lengths of the first lens, the second lens, the third lens, the fourth lens and the fifth lens are f1, f2, f3, f4, f5 respectively, wherein f1, f2, f3, f4, f5 and f satisfy the following ratio: -3.0 <f1 / f<-2.0,-52.0<f2 / f<-51.0,6.0<f3 / f<7.0,15.0<f4 / f<16.0,2.0<f5 / f<3.0。

[0006] Preferably, the first lens satisfies the relationship: 1.5≤N d ≤1.8, V d ≥50.0; the second lens satisfies the relationship: 1.5≤N d ≤1.8, V d ≥50.0; the third lens satisfies the relationship: 1.6≤N d ≤1.9, V d ≤50.0; the fourth lens satisfies the relationship: 1.5≤N d ≤1.8, V d ≥50.0; the fifth lens satisfies the relationship: 1.5≤N d ≤1.8, V d ≥50.0; where N d is the refractive index, V d is the Abbe constant.

[0007] Preferably, the axial distances between the lenses satisfy the following relationship: the air gap between the first lens and the second lens is 2.5 to 3.0 mm; the air gap between the second lens and the third lens is 2.5 to 3.0 mm; the air gap between the third lens and the aperture is 6.0 to 6.5 mm; the air gap between the aperture and the fourth lens is 3.0 to 3.5 mm; the air gap between the fourth lens and the fifth lens is 0.1 to 0.5 mm.

[0008] Preferably, the total optical length TTL of the optical system and the focal length f of the optical system satisfy: TTL / f≤11.

[0009] Preferably, the F number of the optical system is ≤2.4.

[0010] Preferably, the image height H of the optical system and the focal length f of the optical system satisfy: H / f≥1.0.

[0011] Preferably, the aperture of the optical system is located between the third lens and the fourth lens.

[0012] Compared with the prior art, the utility model has the following beneficial effects:

[0013] 1. The imaging angle of the lens to the object is greater than 90 degrees, and it can project a 1cm wide picture at a distance of 100cm while ensuring that the TV Distortion is less than 1%;

[0014] 2. It has the advantages of large aperture, low tolerance sensitivity and good high and low temperature stability;

[0015] 3. Through the reasonable matching of optical lenses, the system structure is compact and reasonable, easy to assemble, with low tolerance sensitivity, and more suitable for large-scale high-yield production;

[0016] 4. The glass-plastic hybrid structure has lower manufacturing cost and lighter weight, which is conducive to the manufacture and installation of modules;

[0017] 5. Able to make good compensation for focal plane displacement at high and low temperatures, and have adaptability to complex environments;

[0018] 6. Corrected various axial chromatic aberrations, vertical chromatic aberrations and high-order chromatic aberrations to ensure that the imaging system can have high imaging quality even at large angles;

[0019] 7. Give full play to the advantages of aspherical lenses in correcting aberrations, meet the requirements of high-definition imaging, have a smaller lens outer diameter and a shorter optical length, and ensure the miniaturization of the lens;

[0020] 8. RI is above 80%.

[0021] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific implementation methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a schematic diagram of the optical structure of an embodiment of the utility model;

[0023] Figure 2 This is a vertical axis chromatic aberration diagram of the full working band of an embodiment of the utility model;

[0024] Figure 3 This is a field curvature distortion diagram of the full working band of an embodiment of the utility model;

[0025] Figure 4 This is the MTF diagram of the full working band of the embodiment of the utility model.

[0026] In the figure: STO-aperture; L1-first lens; L2-second lens; L3-third lens; L4-fourth lens; L5-fifth lens; IMA-imaging surface. DETAILED DESCRIPTION

[0027] In order to make the above features and advantages of the present invention more obvious and easy to understand, embodiments are given below with reference to the accompanying drawings for detailed description as follows.

[0028] like Figures 1 to 4 As shown, a high-brightness and low-cost DMD welcome light lens, the optical system of the lens is composed of a first lens, a second lens, a third lens, an aperture, a fourth lens and a fifth lens arranged in sequence from left to right along the incident light path of the light;

[0029] In the embodiment of the utility model, the first lens and the second lens are both plastic aspherical lenses with negative optical power, which can adjust large-angle light while reducing the distortion of the optical system. Reasonable lens matching enables the optical system to achieve wide-angle, low distortion, low dispersion, large aperture, and low-temperature drift design, while well correcting the on-axis and off-axis aberrations, so that the lens has good imaging quality, such as Figures 2 to 4 The technical indicators achieved by the optical system of this embodiment are as follows:

[0030] (1) Focal length: 3.0 ≤ EFFL ≤ 4.0 mm;

[0031] (2) Aperture F ≤ 2.5;

[0032] (3) Field of view: 2w ≥ 94°;

[0033] (4) Working band: visible light band.

[0034] To achieve the above design parameters, the specific design adopted by the optical system of this embodiment is shown in the following table:

[0035]

[0036]

[0037] The aspheric coefficients of the aspheric lenses of the optical system of this embodiment are as follows:

[0038]

[0039] The optical system of this embodiment reduces the total length of the lens and the radial size of each lens while meeting the imaging performance requirements of the lens by reasonably allocating the optical power, surface shape, center thickness of each lens, and axial distance between each lens, thereby miniaturizing the lens group.

[0040] The utility model is not limited to the above-mentioned best implementation mode. Anyone can derive other forms of high-brightness and low-cost DMD welcome light lenses under the inspiration of the utility model. All equivalent changes and modifications made according to the scope of the patent application of the utility model shall fall within the scope of the utility model.

Claims

1. A high-brightness and low-cost DMD welcome light lens, including an optical system, characterized in that: The optical system of the lens consists of a first lens, a second lens, a third lens, an aperture, a fourth lens and a fifth lens which are arranged in sequence from left to right along the incident light path of the light; without considering the backcurvature caused by the aspheric coefficient, the first lens is a double concave negative lens; the second lens is a meniscus concave negative lens; the third lens is a double convex positive lens; the fourth lens is a meniscus convex positive lens; the fifth lens is a double convex positive lens; the first lens, the second lens, the third lens and the fourth lens are plastic aspheric lenses, and the fifth lens is a glass spherical lens.

2. According to claim 1, a high-brightness and low-cost DMD welcome light lens, characterized in that: The object side surface of the first lens is concave, and the image side surface is concave; the object side surface of the second lens is convex, and the image side surface is concave; the object side surface of the third lens is convex, and the image side surface is convex; the object side surface of the fourth lens is concave, and the image side surface is convex; the object side surface of the fifth lens is convex, and the image side surface is convex.

3. The high-brightness and low-cost DMD welcome light lens according to claim 1, characterized in that: The focal length of the optical system is f, and the focal lengths of the first lens, the second lens, the third lens, the fourth lens, and the fifth lens are f1, f2, f3, f4, and f5, respectively, where f1, f2, f3, f4, and f5 satisfy the following ratio with f: -3.0 <f1 / f<-2.0,-52.0<f2 / f<-51.0, 6.0 <f3 / f<7.0,15.0<f4 / f<16.0,2.0<f5 / f<3.0。 4. The high-brightness and low-cost DMD welcome light lens according to claim 2, characterized in that: The first lens satisfies the relationship: 1.5≤N d ≤1.8, V d ≥50.0; the second lens satisfies the relationship: 1.5≤N d ≤1.8, V d ≥50.0; the third lens satisfies the relationship: 1.6≤N d ≤1.9, V d ≤50.0; the fourth lens satisfies the relationship: 1.5≤N d ≤1.8, V d ≥50.0; the fifth lens satisfies the relationship: 1.5≤N d ≤1.8, V d ≥50.0; where N d is the refractive index, V d is the Abbe constant.

5. The high-brightness and low-cost DMD welcome light lens according to claim 1, characterized in that: The axial distances between the lenses satisfy the following relationship: the air gap between the first lens and the second lens is 2.5 to 3.0 mm; the air gap between the second lens and the third lens is: The air gap between the third lens and the aperture is 2.5~3.0mm; the air gap between the third lens and the aperture is 6.0~6.5mm; the air gap between the aperture and the fourth lens is 3.0~3.5mm; the air gap between the fourth lens and the fifth lens is 0.1~0.5mm.

6. The high-brightness and low-cost DMD welcome light lens according to claim 1, characterized in that: The total optical length TTL of the optical system and the focal length f of the optical system satisfy: TTL / f≤11.

7. The high-brightness and low-cost DMD welcome light lens according to claim 1, characterized in that: The F number of the optical system is ≤2.

4.

8. The high-brightness and low-cost DMD welcome light lens according to claim 1, characterized in that: The image height H of the optical system and the focal length f of the optical system satisfy: H / f≥1.

0.

9. The high-brightness and low-cost DMD welcome light lens according to claim 1, characterized in that: The aperture stop of the optical system is located between the third lens and the fourth lens.

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