A low distortion, low CRA, high pixel miniaturized lens

Abstract

The present invention belongs to the technical field of optical lenses, and discloses a low-distortion, small CRA, high-pixel miniaturized lens, comprising a first plastic lens, a second plastic lens, a third plastic lens, a fourth plastic lens, and a fifth plastic lens arranged in sequence along the optical axis from the object side to the image side, wherein the first plastic lens, the third plastic lens, and the fifth plastic lens have a negative focal length, and the second plastic lens and the fourth plastic lens have a positive focal length; an aperture is arranged between the first plastic lens and the second plastic lens. The present invention can correct distortion and CRA, and can ensure high resolution; when working in an environment of ‑40°C to +60°C, it does not defocus; the mutual compensation of the optical power of positive and negative lenses is adopted, which not only ensures the performance of the optical system, but also reduces the cost of component processing, simplifies the structure, reduces the weight, and is also conducive to mass production, meeting market demand.

Description

Technical Field

[0001] The present invention belongs to the technical field of optical lenses, and in particular relates to a miniaturized lens with low distortion, small CRA and high pixel. Background Art

[0002] As time goes by, there are more and more testing equipment on the market, and there are some new demands in some smart fields. For example, the smart screen field has new requirements for lenses in repeated iterations, such as miniaturization, high pixels, and large aperture. However, most of the products on the market currently have large distortion, small aperture, large CRA, and pixels within 5MP. There is also a problem of low yield, which can no longer meet the current market demand. Summary of the invention

[0003] The object of the present invention is to provide a low-distortion, low-CRA, high-pixel miniaturized lens to solve the above-mentioned problems existing in the prior art.

[0004] In order to achieve the above object, the present invention adopts the following technical solutions:

[0005] A low-distortion, low-CRA, high-pixel miniaturized lens comprises a first plastic lens, a second plastic lens, a third plastic lens, a fourth plastic lens and a fifth plastic lens which are sequentially arranged along an optical axis from an object side to an image side, wherein the first plastic lens, the third plastic lens and the fifth plastic lens have a negative focal length, and the second plastic lens and the fourth plastic lens have a positive focal length; and an aperture is arranged between the first plastic lens and the second plastic lens.

[0006] As a preferred technical solution in the present invention, the amount of light entering the aperture is between 1.4 and 6.0.

[0007] As a preferred technical solution in the present invention, the first plastic lens, the second plastic lens and the fourth plastic lens are all high-refractive-index plastic lenses.

[0008] As a preferred technical solution in the present invention, the first plastic lens, the second plastic lens, the third plastic lens, the fourth plastic lens and the fifth plastic lens are sequentially arranged in a combination of even-order aspherical surfaces.

[0009] As a preferred technical solution of the present invention, the materials of the first plastic lens, the second plastic lens, the third plastic lens, the fourth plastic lens and the fifth plastic lens are different.

[0010] As a preferred technical solution of the present invention, the first plastic lens, the second plastic lens, the third plastic lens, the fourth plastic lens and the fifth plastic lens are all aspherical lenses.

[0011] As a preferred technical solution in the present invention, the low-distortion, small CRA, high-pixel miniaturized lens is a fixed-focus lens with a focal length between 3 and 3.5, an aperture between 1.4 and 6.0, and a total length between 7 and 11 cm.

[0012] As a preferred technical solution in the present invention, the third plastic lens and the fifth plastic lens are both made of low-dispersion material.

[0013] Beneficial effects: The present invention provides a low-distortion detection and calibration lens, comprising a first plastic lens, a second plastic lens, a third plastic lens, a fourth plastic lens and a fifth plastic lens which are sequentially arranged along the optical axis from the object side to the image side, wherein the first plastic lens, the third plastic lens and the fifth plastic lens have a negative focal length, and the second plastic lens and the fourth plastic lens have a positive focal length, wherein the fifth plastic lens plays a role in correcting distortion, and the fourth plastic lens and the fifth plastic lens play a role in correcting distortion and correcting CRA to a certain extent, thereby ensuring high resolution; when working in an environment of -40°C to +60°C, it does not defocus; the mutual compensation of the optical focal length of positive and negative lenses is adopted, which not only ensures the performance of the optical system, but also reduces the processing cost of parts, simplifies the structure, reduces the weight, and is also conducive to mass production, meeting market demand. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic structural diagram of a low-distortion, small-CRA, high-pixel miniaturized lens of the present invention;

[0015] Figure 2 The MTF curve of the low-distortion, low-CRA, high-pixel miniaturized lens of the present invention in the working band of 700nm~1100nm;

[0016] Figure 3 is a focus curve diagram according to an embodiment of the present invention;

[0017] Figure 4 The point diagram of the low-distortion, small-CRA, high-pixel miniaturized lens of the present invention;

[0018] Figure 5 This is a relative illumination diagram of the low-distortion, small-CRA, high-pixel miniaturized lens of the present invention.

[0019] In the figure: 1-first plastic lens; 2-second plastic lens; 3-third plastic lens; 4-fourth plastic lens; 5-fifth plastic lens. DETAILED DESCRIPTION

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the present invention will be briefly introduced below in combination with the drawings and the description of the embodiments or the prior art. Obviously, the following description of the structure of the drawings is only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. It should be noted that the description of these embodiments is used to help understand the present invention, but does not constitute a limitation of the present invention.

[0021] Example:

[0022] like Figure 1 As shown, this embodiment provides a low-distortion, low-CRA, high-pixel miniaturized lens, comprising a first plastic lens 1, a second plastic lens 2, a third plastic lens 3, a fourth plastic lens 4, and a fifth plastic lens 5, which are sequentially arranged along the optical axis from the object side to the image side, wherein the first plastic lens 1, the third plastic lens 3, and the fifth plastic lens 5 have a negative focal length, and the second plastic lens 2 and the fourth plastic lens 4 have a positive focal length; an aperture is arranged between the first plastic lens 1 and the second plastic lens 2, and the amount of light entering the aperture is between 1.4 and 6.0, wherein the fifth plastic lens 5 plays a role in correcting distortion, and the fourth plastic lens 4 and the fifth plastic lens 5 play a role in correcting distortion and correcting CRA to a certain extent.

[0023] Furthermore, the first plastic lens 1, the second plastic lens 2 and the fourth plastic lens 4 are all high refractive index plastic lenses. Due to the curvature system of the first plastic lens 1, the second plastic lens 2, the third plastic lens 3, the fourth plastic lens 4 and the fifth plastic lens 5 and the coordination of multiple plastic sheets, the distortion can be reduced to less than 1% to achieve a low distortion function.

[0024] Furthermore, in order to achieve a resolution of more than 8 million, the first plastic lens 1, the second plastic lens 2, the third plastic lens 3, the fourth plastic lens 4 and the fifth plastic lens 5 are arranged in sequence by a combination of even-order aspherical surfaces, which can effectively correct aberrations such as spherical aberration, coma, astigmatism, field curvature, etc., thereby improving the resolution quality of the lens. At the same time, the materials of the first plastic lens 1, the second plastic lens 2, the third plastic lens 3, the fourth plastic lens 4 and the fifth plastic lens 5 are different, and the aberrations can be reduced by matching the dispersion coefficient. At the same time, the image quality can be further improved through the high-precision plastic lens barrel, thereby achieving an ideal resolution.

[0025] Furthermore, in order to achieve the cost reduction requirement, the present invention applies lenses in the field of smart door locks and smart screens, and also uses a wavelength band of 400-1100nm. When designing, low distortion, miniature, high pixel, and low cost are mainly considered. At the same time, the image plane reserves a chip that meets 1 / 2.5. At the same time, the structure needs to consider an extremely simple way to focus, that is, thread focusing. The coating adopts a wavelength band of 400~900nm. The lens is considered in the stray light evaluation stage, and no ink extinction is required in the later stage.

[0026] Furthermore, the low distortion, small CRA, high pixel miniaturized lens of the present invention can be used as an athermal fixed-focus high-definition optical lens, wherein the first plastic lens 1, the second plastic lens 2, the third plastic lens 3, the fourth plastic lens 4 and the fifth plastic lens 5 are all aspherical lenses. Meanwhile, the low distortion, small CRA, high pixel miniaturized lens (athermal fixed-focus high-definition optical lens) of the present invention is a fixed-focus lens with a focal length of 3 to 3.5, an aperture of 1.4 to 6.0, and a total length of 7 to 11 cm, while ensuring high resolution; a temperature compensation design is adopted to operate in an environment of -40°C to +60°C without defocusing; mutual compensation of the optical power of positive and negative lenses is adopted to not only ensure the performance of the optical system, but also reduce the processing cost of parts, simplify the structure, reduce the weight, and facilitate mass production, meeting market demand; preferably, the third plastic lens 3 and the fifth plastic lens 5 are both made of low-dispersion material, and while using low-dispersion material, the image quality can also be improved.

[0027] The relevant parameters of each lens of the low distortion, small CRA, high pixel miniaturized lens provided by the present invention are shown in Table 1 and Table 2 below:

[0028] Table 1: Relevant parameters of each lens

[0029]

[0030] Table 2: Coefficient values ​​of even-order aspheric surfaces of corresponding lenses

[0031]

[0032] In Tables 1 and 2 above, S1 and S2 correspond to the two sides of the first plastic lens 1 respectively, S3 and S4 correspond to the two sides of the second plastic lens 2 respectively, S5 and S6 correspond to the two sides of the third plastic lens 3 respectively, S7 and S8 correspond to the two sides of the fourth plastic lens 4 respectively, and S9 and S10 correspond to the two sides of the fifth plastic lens 5 respectively.

[0033] Please refer to Figure 2 and Figure 3 As shown, Figure 2 and Figure 3The MTF curve and the focus curve of an embodiment of a low-distortion, low-CRA, high-pixel miniaturized lens of the present invention in the working band of 400nm to 1100nm are shown respectively. Figure 2 and Figure 3 It can be seen that the low-distortion, small-CRA, high-pixel miniaturized lens of the present invention has a good focusing effect, can ensure high resolution, and has good imaging quality.

[0034] Please refer to Figure 5 , Figure 5 FIG. 1 shows a relative illumination diagram of an embodiment of a low distortion detection and calibration lens of the present invention, wherein the horizontal axis is the field of view and the vertical axis is the relative illumination. Figure 4 It can be seen from the figure that the relative illumination of this embodiment reaches more than 80%, which has good relative illumination.

[0035] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the protection scope of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A low distortion, low CRA, high pixel miniaturized lens, characterized in that: The invention comprises a first plastic lens (1), a second plastic lens (2), a third plastic lens (3), a fourth plastic lens (4) and a fifth plastic lens (5) which are arranged in sequence along the optical axis from the object side to the image side, wherein the first plastic lens (1), the third plastic lens (3) and the fifth plastic lens (5) have a negative focal length, and the second plastic lens (2) and the fourth plastic lens (4) have a positive focal length; an aperture is arranged between the first plastic lens (1) and the second plastic lens (2); the number of lenses having optical power in the low-distortion, small CRA and high-pixel miniaturized lens is five, and the parameters of each lens are as follows: Among them, S1 and S2 correspond to the two sides of the first plastic lens respectively, S3 and S4 correspond to the two sides of the second plastic lens respectively, S5 and S6 correspond to the two sides of the third plastic lens respectively, S7 and S8 correspond to the two sides of the fourth plastic lens respectively, and S9 and S10 correspond to the two sides of the fifth plastic lens respectively.

2. The low distortion, small CRA, high pixel miniaturized lens according to claim 1, characterized in that: The first plastic lens (1), the second plastic lens (2), the third plastic lens (3), the fourth plastic lens (4) and the fifth plastic lens (5) are made of different materials.

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