Infrared DMS lens and camera device with same

Abstract

The infrared DMS lens comprises a first lens, a second lens and a third lens which are sequentially arranged from an object space to an image space along an optical axis, the first lens has negative focal power, the object side surface of the first lens is a concave surface, the image side surface of the first lens is a convex surface, the second lens has positive focal power, the object side surface of the second lens is a convex surface, and the third lens is a concave surface. The third lens has negative focal power, the object side surface of the third lens is a concave surface, the image side surface of the third lens is a convex surface, and the lens meets the conditional expressions that (FOV * f) / h is larger than or equal to 65 and smaller than or equal to 70, f is the whole set of focal length of the infrared DMS lens, FOV is the maximum field angle of the infrared DMS lens, and h is the image height corresponding to the maximum field angle. The infrared DMS lens provided by the utility model has the characteristics of miniaturization, high stability, wide visual field, low cost and the like, and can meet the use requirements at the temperature of-40 DEG C to 105 DEG C while realizing good image quality.

Description

Technical Field

[0001] This utility model belongs to the field of optical lens technology, specifically relating to an infrared DMS lens and a camera device having the same. Background Technology

[0002] With the rapid development and widespread application of autonomous driving assistance systems (ADAS) in automobiles, the requirements for monitoring vehicle conditions and ensuring vehicle safety are constantly increasing. DMS cameras are primarily used to monitor driver status, such as fatigue, inattention, or other dangerous behaviors, accurately detecting facial expressions and head movements under various lighting conditions to provide accurate and timely visual information about the driving environment. While there are many types of automotive infrared lenses currently available, most suffer from the following problems: numerous lenses, large size, low resolution, poor application performance, small aperture, and high cost. Utility Model Content

[0003] To address the technical problems existing in the prior art, the purpose of this utility model is to provide an infrared DMS lens and a camera device having the same.

[0004] To achieve the above objectives and technical effects, the technical solution adopted by this utility model is as follows:

[0005] An infrared DMS lens includes a first lens, a second lens, and a third lens arranged sequentially along the optical axis from the object side to the image side. The first lens has negative optical power, with its object-side surface being concave and its image-side surface being convex. The second lens has positive optical power, with both its object-side and image-side surfaces being convex. The third lens has negative optical power, with its object-side surface being concave and its image-side surface being convex. The infrared DMS lens satisfies the following condition:

[0006] 65≤(FOV×f) / h≤70;

[0007] Where f is the total focal length of the infrared DMS lens, FOV is the maximum field of view of the infrared DMS lens, and h is the image height corresponding to the maximum field of view.

[0008] Furthermore, the infrared DMS lens satisfies the following condition:

[0009] 2.8≤TTL / f≤3.5;

[0010] Where TTL is the distance on the optical axis from the center of the first surface of the lens to the imaging surface.

[0011] Furthermore, the infrared DMS lens satisfies the following condition:

[0012] 0.3≤BFL / TTL≤0.4;

[0013] Wherein, BFL is the distance on the optical axis from the center of the image side of the third lens to the imaging surface of the lens, and TTL is the distance on the optical axis from the center of the first surface of the lens to the imaging surface.

[0014] Furthermore, the infrared DMS lens satisfies the following condition:

[0015] (D+TTL) / FNO≤6.5;

[0016] Where D is the effective optical aperture of the first lens, TTL is the distance from the center of the first surface of the lens to the imaging surface on the optical axis, and FNO is the relative aperture of the infrared DMS lens.

[0017] Furthermore, the effective focal length of the first lens is f1, the effective focal length of the second lens is f2, and the effective focal length of the third lens is f3, satisfying the following condition:

[0018] -13≤f1 / f≤-8;

[0019] 0.85≤f² / f≤1.15;

[0020] -5.2≤f3 / f≤-2.2.

[0021] Furthermore, the first lens has a refractive index of Nd1, the second lens has a refractive index of Nd2, and the third lens has a refractive index of Nd3, satisfying the following condition:

[0022] 1.75≤Nd1≤2.05;

[0023] 1.95≤Nd2≤2.05;

[0024] 1.45≤Nd3≤1.72.

[0025] Furthermore, the Abbe number of the first lens is Vd1, the Abbe number of the second lens is Vd2, and the Abbe number of the third lens is Vd3, satisfying the following condition:

[0026] 20.2≤Vd1≤52;

[0027] 22.5≤Vd1≤29.5;

[0028] 21.2≤Vd3≤72.2.

[0029] Furthermore, an aperture stop is provided between the first lens and the second lens; or, an aperture stop is provided between the first lens and the object.

[0030] Furthermore, the first lens, the second lens, and the third lens are glass spherical lenses.

[0031] This utility model also discloses a camera device, including an electronic photosensitive element and an infrared DMS lens as described above.

[0032] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0033] This utility model discloses an infrared DMS lens and a camera device having the same. The infrared DMS lens features miniaturization, high stability, wide field of view, and low cost. While achieving good image quality, it can also meet the usage requirements at temperatures ranging from -40℃ to 105℃. Attached Figure Description

[0034] Figure 1 This is a schematic diagram of the structure of Embodiment 1 of the present invention;

[0035] Figure 2 This is a schematic diagram of the MTF curve of Embodiment 1 of this utility model;

[0036] Figure 3 This is a schematic diagram of the 83 lp / mm defocus curve of Embodiment 1 of this utility model at a low temperature of -40℃;

[0037] Figure 4 This is a schematic diagram of the defocusing curve of Embodiment 1 of this utility model at a high temperature of 105°C with a diameter of 83 lp / mm.

[0038] Figure 5 This is a schematic diagram of the structure of Embodiment 2 of this utility model;

[0039] Figure 6 This is a schematic diagram of the MTF curve of Embodiment 2 of this utility model;

[0040] Figure 7 This is a schematic diagram of the 83 lp / mm defocusing curve of Embodiment 2 of this utility model at a low temperature of -40℃;

[0041] Figure 8 This is a schematic diagram of the defocusing curve of 83 lp / mm at a high temperature of 105℃ for Embodiment 2 of this utility model;

[0042] Figure 9 This is a schematic diagram of the structure of Embodiment 3 of this utility model;

[0043] Figure 10 This is a schematic diagram of the MTF curve of Embodiment 3 of this utility model;

[0044] Figure 11 This is a schematic diagram of the 83 lp / mm defocusing curve of Embodiment 3 of this utility model at a low temperature of -40℃;

[0045] Figure 12This is a schematic diagram of the defocusing curve of 83 lp / mm at a high temperature of 105℃ for Embodiment 3 of this utility model. Detailed Implementation

[0046] The present invention will now be described in detail so that its advantages and features can be more easily understood by those skilled in the art, thereby providing a clearer and more definite definition of the scope of protection of the present invention.

[0047] The following provides a brief overview of one or more aspects to offer a basic understanding of them. This overview is not an exhaustive summary of all conceived aspects, nor is it intended to identify key or decisive elements of all aspects, nor to define the scope of any or all aspects. Its sole purpose is to present some concepts of one or more aspects in a simplified form to prepare for the more detailed descriptions that follow.

[0048] like Figure 1-12 As shown, an infrared DMS lens includes a first lens 1, a second lens 2, and a third lens 3 arranged sequentially along the optical axis from the object side to the image side.

[0049] The first lens 1 has negative optical power, and the object side of the first lens 1 is concave and the image side is convex.

[0050] The second lens 2 has positive optical power, and the object side and image side of the second lens 2 are both convex.

[0051] The third lens 3 has negative optical power, the object side of the third lens 3 is concave, and the image side of the third lens 3 is convex.

[0052] In some embodiments, the first lens 1, the second lens 2, and the third lens 3 are glass spherical lenses, and an aperture 4 is provided between the first lens 1 and the second lens 2, or an aperture 4 is provided between the object side and the first lens 1.

[0053] In some implementations, the total focal length of the infrared DMS lens is f, the effective focal length of the first lens 1 is f1, the effective focal length of the second lens 2 is f2, and the effective focal length of the third lens 3 is f3, satisfying the following conditions:

[0054] -13≤f1 / f≤-8;

[0055] 0.85≤f² / f≤1.15;

[0056] -5.2≤f3 / f≤-2.2.

[0057] In some embodiments, the refractive index of the first lens 1 is Nd1, the refractive index of the second lens 2 is Nd2, and the refractive index of the third lens 3 is Nd3, satisfying the following condition:

[0058] 1.75≤Nd1≤2.05;

[0059] 1.95≤Nd2≤2.05;

[0060] 1.45≤Nd3≤1.72.

[0061] In some embodiments, the Abbe number of the first lens 1 is Vd1, the Abbe number of the second lens 2 is Vd2, and the Abbe number of the third lens 3 is Vd3, satisfying the following condition:

[0062] 20.2≤Vd1≤52;

[0063] 22.5≤Vd1≤29.5;

[0064] 21.2≤Vd3≤72.2.

[0065] In some implementations, the maximum field of view (FOV) of the infrared DMS lens is denoted as FOV, and the image height corresponding to the maximum FOV is denoted as h. FOV, f, and h satisfy the following condition:

[0066] With a field of view of 65 ≤ (FOV×f) / h ≤ 70, a larger maximum field of view is achieved at the same image height, resulting in a wider field of view, reduced blind spots, and improved security and monitoring effectiveness.

[0067] In some implementations, TTL is the distance along the optical axis from the center of the first surface of the lens to the imaging plane, and TTL and f satisfy the following condition:

[0068] 2.8≤TTL / f≤3.5.

[0069] In some implementations, BFL is the distance along the optical axis from the center of the image side of the third lens 3 to the imaging plane of the lens, and BFL satisfies the conditional expression with TTL:

[0070] 0.3≤BFL / TTL≤0.4.

[0071] In some embodiments, D is the effective optical aperture of the first lens 1, TTL is the distance from the center of the first surface of the lens to the imaging plane on the optical axis, and FNO is the relative aperture of the lens. D, TTL, and FNO satisfy the following condition:

[0072] (D+TTL) / FNO≤6.5.

[0073] Example 1

[0074] like Figure 1-4As shown, an infrared DMS lens includes a first lens 1, a second lens 2, and a third lens 3 arranged sequentially from the object side to the image side along the optical axis. An aperture 4 is provided between the first lens 1 and the second lens 2. A filter 5, a protective glass 6, and an IMA 7 are sequentially arranged on the side of the third lens 3 closest to the image side.

[0075] The optical parameters of each lens and aperture in Example 1 are shown in Table 1.

[0076] Table 1

[0077]

[0078] The surface numbers in Table 1 are assigned according to the surface sequence of each lens; Infinity indicates that the surface is a plane with an infinite radius of curvature; Thickness represents the central axial distance between the current surface and the next surface; Refractive index represents the ability of the material between the current surface and the next surface to deflect light; a blank space indicates that the current position is air with a refractive index of 1; Abbe number represents the dispersion characteristics of the material between the current surface and the next surface; a blank space indicates that the current position is air.

[0079] The optical parameters of Example 1 are shown in Table 2.

[0080] Table 2

[0081]

[0082]

[0083] Figure 2 This is a schematic diagram of the MTF curve for Example 1, where MTF represents the overall imaging quality of the infrared DMS lens. A higher MTF value indicates a clearer image. The horizontal axis represents spatial frequency in lp / mm, and the vertical axis represents the normalized MTF (OTF coefficient), which has no unit. T represents meridional (displayed as a dashed line), and S represents arcuate (displayed as a solid line). Different lines extend upwards to represent different field-of-view angles. Figure 2 It can be seen that the infrared DMS lens of Example 1 has excellent imaging quality in the imaging field from 0 to 0.7.

[0084] Figure 3 This diagram illustrates the defocus curve of the infrared DMS lens of Example 1 at a low temperature of -40°C with a speed of 83 lp / mm. Figure 4 This diagram illustrates the defocus curve of the infrared DMS lens of Example 1 at a high temperature of 105°C with a speed of 83 lp / mm. Figure 3 and Figure 4 The vertical directions all represent the normalized MTF (OTF coefficient), which has no unit. The horizontal directions all represent the optical back focus offset of the infrared DMS lens, in mm. Figure 3and Figure 4 It can be seen that the optical back focus of the infrared DMS lens is controlled within ±0.01mm as the temperature ranges from -40℃ to 105℃, indicating that the infrared DMS lens has good high and low temperature performance and can meet the requirements for use of optical lenses in temperatures ranging from -40℃ to 105℃.

[0085] Example 2

[0086] like Figure 5-8 As shown, an infrared DMS lens includes a first lens 1, a second lens 2, and a third lens 3 arranged sequentially from the object side to the image side along the optical axis. An aperture 4 is provided between the object side and the first lens 1. A filter 5, a protective glass 6, and an IMA 7 are sequentially arranged on the side of the third lens 3 closest to the image side.

[0087] The optical parameters of each lens and aperture in Example 2 are shown in Table 3.

[0088] Table 3

[0089]

[0090]

[0091] The optical parameters of Example 2 are shown in Table 4.

[0092] Table 4

[0093] The focal length f1 of the first lens -34.68 The focal length f2 of the second lens 3.80 The focal length of the third lens is f3. -16.88 f 3.67 BFL 4.3 FOV 87.4 D 1.793 h 4.7 FNO 2.05 TTL 11.1 (FOV×f) / h 68.25 TTL / f 3.02 BFL / TTL 0.39 (D+TTL) / FNO 6.29

[0094] Figure 6 This is a schematic diagram of the MTF curve for Example 2. MTF represents the overall imaging quality of the infrared DMS lens; a higher MTF value results in a clearer image. The horizontal axis represents spatial frequency in lp / mm, and the vertical axis represents the normalized MTF (OTF coefficient), which has no unit. T represents meridional (displayed as a dashed line), and S represents arcuate (displayed as a solid line). Different lines extend upwards to represent different field-of-view angles. Figure 6 It can be seen that the infrared DMS lens of Example 2 has excellent imaging quality in the imaging field from 0 to 0.7.

[0095] Figure 7 This diagram illustrates the defocus curve of the infrared DMS lens of Example 2 at a low temperature of -40°C with a speed of 83 lp / mm. Figure 8 This diagram illustrates the defocus curve of the infrared DMS lens of Example 2 at a high temperature of 105°C with a speed of 83 lp / mm. Figure 7 and Figure 8 The vertical directions all represent the normalized MTF (OTF coefficient), which has no unit. The horizontal directions all represent the optical back focus offset of the infrared DMS lens, in mm. Figure 7 and Figure 8 It can be seen that the optical back focus of the infrared DMS lens is controlled within ±0.01mm as the temperature ranges from -40℃ to 105℃, indicating that the infrared DMS lens has good high and low temperature performance and can meet the requirements for use of optical lenses in temperatures ranging from -40℃ to 105℃.

[0096] The rest is the same as in Example 1.

[0097] Example 3

[0098] like Figure 9-12 As shown, an infrared DMS lens includes a first lens 1, a second lens 2, and a third lens 3 arranged sequentially from the object side to the image side along the optical axis. An aperture 4 is provided between the object side and the first lens 1. A filter 5, a protective glass 6, and an IMA 7 are sequentially arranged on the side of the third lens 3 closest to the image side.

[0099] The optical parameters of each lens and aperture in Example 3 are shown in Table 5.

[0100] Table 5

[0101]

[0102] The optical parameters of Example 3 are shown in Table 6.

[0103] Table 6

[0104]

[0105]

[0106] Figure 10 This is a schematic diagram of the MTF curve for Example 3. MTF represents the overall imaging quality of the infrared DMS lens; a higher MTF value indicates a clearer image. The horizontal axis represents spatial frequency in lp / mm, and the vertical axis represents the normalized MTF (OTF coefficient), which has no unit. T represents meridional (displayed as a dashed line), and S represents arcuate (displayed as a solid line). Different lines extend upwards to represent different field-of-view angles. Figure 6 It can be seen that the infrared DMS lens of Example 3 has excellent imaging quality in the imaging field from 0 to 0.7.

[0107] Figure 11 This diagram illustrates the defocus curve of the infrared DMS lens of Example 3 at a low temperature of -40°C with a speed of 83 lp / mm. Figure 12 This diagram illustrates the defocus curve of the infrared DMS lens of Example 3 at a high temperature of 105°C with a speed of 83 lp / mm. Figure 11 and Figure 12The vertical directions all represent the normalized MTF (OTF coefficient), which has no unit. The horizontal directions all represent the optical back focus offset of the infrared DMS lens, in mm. Figure 11 and Figure 12 It can be seen that the optical back focus of the infrared DMS lens is controlled within ±0.01mm as the temperature ranges from -40℃ to 105℃, indicating that the infrared DMS lens has good high and low temperature performance and can meet the requirements for use of optical lenses in temperatures ranging from -40℃ to 105℃.

[0108] The rest is the same as in Example 1.

[0109] The parts or structures not specifically described in this utility model can be made using existing technology or existing products, and will not be elaborated here.

[0110] The above description is merely an embodiment of this utility model and does not limit the patent scope of this utility model. Any equivalent structural or procedural transformations made based on the content of this utility model specification, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this utility model.

Claims

1. An infrared DMS lens, characterized in that, The infrared DMS lens comprises a first lens, a second lens, and a third lens arranged sequentially from the object side to the image side along the optical axis. The first lens has negative optical power, with a concave object side and a convex image side. The second lens has positive optical power, with a convex object side and a convex image side. The third lens has negative optical power, with a concave object side and a convex image side. The infrared DMS lens satisfies the following condition: 65≤(FOV×f) / h≤70; Where f is the total focal length of the infrared DMS lens, FOV is the maximum field of view of the infrared DMS lens, and h is the image height corresponding to the maximum field of view.

2. The infrared DMS lens according to claim 1, characterized in that, The infrared DMS lens satisfies the following condition: 2.8≤TTL / f≤3.5; Where TTL is the distance on the optical axis from the center of the first surface of the lens to the imaging surface.

3. An infrared DMS lens according to claim 1, characterized in that, The infrared DMS lens satisfies the following condition: 0.3≤BFL / TTL≤0.4; Wherein, BFL is the distance on the optical axis from the center of the image side of the third lens to the imaging surface of the lens, and TTL is the distance on the optical axis from the center of the first surface of the lens to the imaging surface.

4. An infrared DMS lens according to claim 1, characterized in that, The infrared DMS lens satisfies the following condition: (D+TTL) / FNO≤6.5; Where D is the effective optical aperture of the first lens, TTL is the distance from the center of the first surface of the lens to the imaging surface on the optical axis, and FNO is the relative aperture of the infrared DMS lens.

5. An infrared DMS lens according to claim 1, characterized in that, The effective focal length of the first lens is f1, the effective focal length of the second lens is f2, and the effective focal length of the third lens is f3, satisfying the following condition: -13≤f1 / f≤-8; 0.85≤f² / f≤1.15; -5.2≤f3 / f≤-2.

2.

6. An infrared DMS lens according to claim 1, characterized in that, The first lens has a refractive index of Nd1, the second lens has a refractive index of Nd2, and the third lens has a refractive index of Nd3, satisfying the following condition: 1.75≤Nd1≤2.05; 1.95≤Nd2≤2.05; 1.45≤Nd3≤1.

72.

7. An infrared DMS lens according to claim 1, characterized in that, The Abbe number of the first lens is Vd1, the Abbe number of the second lens is Vd2, and the Abbe number of the third lens is Vd3, satisfying the following condition: 20.2≤Vd1≤52; 22.5≤Vd1≤29.5; 21.2≤Vd3≤72.

2.

8. An infrared DMS lens according to claim 1, characterized in that, An aperture stop is provided between the first lens and the second lens; or, an aperture stop is provided between the first lens and the object.

9. An infrared DMS lens according to claim 1, characterized in that, The first lens, the second lens, and the third lens are glass spherical lenses.

10. A camera device, characterized in that, It includes an electronic photosensitive element and an infrared DMS lens as described in any one of claims 1-9.

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