An infrared wide-angle lens

Abstract

This invention provides an infrared wide-angle lens, comprising a first lens, a second lens, an aperture stop, a third lens, a fourth lens, a fifth lens, and a filter arranged sequentially from the object side to the image side along the optical axis. The object side and image side of the optical axis region of the first lens are concave, while the object side and image side of the optical axis region of the second lens are convex and concave. Through the structural and parameter settings of the first, second, third, fourth, and fifth lenses, the infrared wide-angle lens enables the product's field of view to reach 90 to 120 degrees, significantly improving the product's field of view.

Description

Technical Field

[0001] This invention relates to the field of wide-angle lens technology, and in particular to an infrared wide-angle lens. Background Technology

[0002] An infrared wide-angle lens is a photographic lens with a shorter focal length than a standard lens, a wider angle of view than a standard lens, a longer focal length than a fisheye lens, and a narrower angle of view than a fisheye lens. Infrared wide-angle lenses are further divided into two types: ordinary wide-angle lenses and ultra-wide-angle lenses.

[0003] Existing infrared wide-angle lenses generally have a field of view of less than 90 degrees, resulting in a small field of view. Moreover, their aperture values ​​are generally around 1.8 to 2.0, which is a large aperture value. Summary of the Invention

[0004] The purpose of this invention is to provide an infrared wide-angle lens to solve the problems of small field of view and large aperture value in existing infrared wide-angle lenses.

[0005] This invention provides an infrared wide-angle lens, comprising a first lens, a second lens, an aperture stop, a third lens, a fourth lens, a fifth lens, and a filter arranged sequentially from the object side to the image side along the optical axis. The object side and image side of the first lens in the optical axis region are concave, while the object side and image side of the second lens in the optical axis region are convex. The infrared wide-angle lens satisfies the following relationship:

[0006] f1'<0, f2'>0, f3'>0, f4'>0, f5'<0;

[0007] 0.25 <IH / TTL<0.38;

[0008] -1.25 <f1' / f3'<-0.6,0.2<f1' / f5'<0.5,-0.4<f' / f12'<-0.15,0.8<f' / f345'<1.5,-4<f12' / f345'<-2;

[0009] Wherein, f' is the focal length of the infrared wide-angle lens, TTL is the distance between the object side and the image plane of the first lens, IH is the half-image height of the infrared wide-angle lens, the focal lengths of the first lens to the fifth lens are f1', f2', f3', f4', and f5' respectively, f12' is the combined focal length of the first lens and the second lens, and f345' is the combined focal length of the third lens, the fourth lens, and the fifth lens.

[0010] The aforementioned infrared wide-angle lens, through the structure and parameter settings of the first, second, third, fourth, and fifth lenses, enables the product's field of view to reach 90 to 120 degrees, greatly improving the product's field of view.

[0011] Furthermore, the refractive index of the first lens, the second lens, the third lens, and the fourth lens are all greater than 1.50, and the Abbe number is greater than 18.

[0012] Furthermore, the fifth lens has a refractive index greater than 1.50 and an Abbe number greater than 50.

[0013] Furthermore, the aperture number of the infrared wide-angle lens is greater than or equal to 1.1.

[0014] Furthermore, the infrared wide-angle lens also satisfies the following relationship:

[0015] 0.6 <SAG11 / SAG12<1.1;

[0016] 0.8 <SAG21 / SAG22<1.28,

[0017] -0.75 <SAG51 / SAG52<0.38;

[0018] Wherein, SAG11 is the sagitta of the object-side surface of the first lens, SAG12 is the sagitta of the image-side surface of the first lens, SAG21 is the sagitta of the object-side surface of the second lens, SAG22 is the sagitta of the image-side surface of the second lens, SAG51 is the sagitta of the object-side surface of the fifth lens, and SAG52 is the sagitta of the image-side surface of the fifth lens.

[0019] Furthermore, the infrared wide-angle lens also satisfies the following relationship:

[0020] 1.2 <Y11 / Y21<1.7;

[0021] 0.95 <Y11 / Y52<1.35;

[0022] Wherein, Y11 is the maximum effective radius of the object side of the first lens, Y21 is the maximum effective radius of the object side of the second lens, and Y52 is the maximum effective radius of the image side of the fifth lens.

[0023] Furthermore, the infrared wide-angle lens also satisfies the following relationship:

[0024] 0.08 < |R1+R2 / R1-R2| < 0.6;

[0025] 2.55 < |R3+R4 / R3-R4| < 15;

[0026] 0.25 < |R1 / R2| < 0.9;

[0027] 0.35 <R3 / R4<0.95;

[0028] Wherein, R1 is the radius of curvature of the object side of the first lens, R2 is the radius of curvature of the image side of the first lens, R3 is the radius of curvature of the object side of the second lens, and R4 is the radius of curvature of the image side of the second lens.

[0029] Furthermore, the infrared wide-angle lens also satisfies the following relationship:

[0030] 0.36≤T2 / T4≤0.65;

[0031] 1.45≤T4 / T5≤2.7;

[0032] Wherein, T2 is the center thickness of the second lens, T4 is the center thickness of the fourth lens, and T5 is the center thickness of the fifth lens.

[0033] Furthermore, the infrared wide-angle lens also satisfies the following relationship:

[0034] 0.05 <A1 / A2<0.1;

[0035] 12 <A3 / A4<20;

[0036] 0.04≤A4 / T5≤0.11;

[0037] Wherein, A1 is the air gap between the first lens and the second lens, A2 is the air gap between the second lens and the third lens, A3 is the air gap between the third lens and the fourth lens, A4 is the air gap between the fourth lens and the fifth lens, and T5 is the center thickness of the fifth lens.

[0038] Furthermore, the infrared wide-angle lens also satisfies the following relationship:

[0039] 0.17 <T12 / TTL<0.25;

[0040] 0.25 <T12 / T345<0.55;

[0041] Wherein, T12 is the combined center thickness of the first lens and the second lens, and T345 is the combined center thickness of the third lens, the fourth lens and the fifth lens. Attached Figure Description

[0042] Figure 1 This is a schematic diagram of the structure of the infrared wide-angle lens in the first embodiment of the present invention;

[0043] Figure 2 for Figure 1 The multicolor diffraction modulation transfer function curve of the infrared wide-angle lens in the image under infrared light characteristics;

[0044] Figure 3 for Figure 1 The curve of the Y-field of view of the infrared wide-angle lens under relative illumination;

[0045] Figure 4 for Figure 1 The transfer function curve of multicolor diffraction defocus modulation under infrared light characteristics of the infrared wide-angle lens;

[0046] Figure 5 This is a schematic diagram of the structure of the infrared wide-angle lens in the first embodiment of the present invention;

[0047] Figure 6 for Figure 5 The multicolor diffraction modulation transfer function curve of the infrared wide-angle lens in the image under infrared light characteristics;

[0048] Figure 7 for Figure 5 The curve of the Y-field of view of the infrared wide-angle lens under relative illumination;

[0049] Figure 8 for Figure 5 The transfer function curve of multicolor diffraction defocus modulation under infrared light characteristics of the infrared wide-angle lens;

[0050] Figure 9 This is a schematic diagram of the structure of the infrared wide-angle lens in the first embodiment of the present invention;

[0051] Figure 10 for Figure 9 The multicolor diffraction modulation transfer function curve of the infrared wide-angle lens in the image under infrared light characteristics;

[0052] Figure 11 for Figure 9 The curve of the Y-field of view of the infrared wide-angle lens under relative illumination;

[0053] Figure 12 for Figure 9 The transfer function curve of multicolor diffraction defocus modulation under infrared light characteristics of the infrared wide-angle lens;

[0054] Figure 13 This is a schematic diagram of the structure of the infrared wide-angle lens in the first embodiment of the present invention;

[0055] Figure 14 for Figure 13 The multicolor diffraction modulation transfer function curve of the infrared wide-angle lens in the image under infrared light characteristics;

[0056] Figure 15 for Figure 13 The curve of the Y-field of view of the infrared wide-angle lens under relative illumination;

[0057] Figure 16 for Figure 13 The transfer function curve of multicolor diffraction defocus modulation under infrared light characteristics of the infrared wide-angle lens;

[0058] Figure 17 This is a schematic diagram of the structure of the infrared wide-angle lens in the first embodiment of the present invention;

[0059] Figure 18 for Figure 17 The multicolor diffraction modulation transfer function curve of the infrared wide-angle lens in the image under infrared light characteristics;

[0060] Figure 19 for Figure 17 The curve of the Y-field of view of the infrared wide-angle lens under relative illumination;

[0061] Figure 20 for Figure 17 The transfer function curve of the multicolor diffraction defocus modulation of the infrared wide-angle lens under the infrared light characteristics.

[0062] The following detailed description, in conjunction with the accompanying drawings, will further illustrate the present invention. Detailed Implementation

[0063] To facilitate understanding of the present invention, a more complete description will be given below with reference to the accompanying drawings. Several embodiments of the invention are illustrated in the drawings. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

[0064] It should be noted that when a component is said to be "fixed to" another component, it can be directly on the other component or there may be an intervening component. When a component is said to be "connected to" another component, it can be directly connected to the other component or there may be an intervening component. The terms "vertical," "horizontal," "left," "right," and similar expressions used in this document are for illustrative purposes only.

[0065] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0066] Example 1

[0067] Please see Figures 1 to 4 The first embodiment of the present invention provides an infrared wide-angle lens, comprising a first lens 11, a second lens 12, an aperture stop, a third lens 13, a fourth lens 14, a fifth lens 15, and a filter 16 arranged sequentially from the object side to the image side along the optical axis. The object side 111 of the optical axis region of the first lens 11 is concave, and the image side 112 is concave. The object side 121 of the optical axis region of the second lens 12 is convex, and the image side 122 is concave. The infrared wide-angle lens satisfies the following relationship:

[0068] f1'<0, f2'>0, f3'>0, f4'>0, f5'<0;

[0069] 0.25 <IH / TTL<0.38;

[0070] -1.25 <f1' / f3'<-0.6,0.2<f1' / f5'<0.5,-0.4<f' / f12'<-0.15,0.8<f' / f345'<1.5,-4<f12' / f345'<-2;

[0071] Wherein, f' is the focal length of the infrared wide-angle lens, TTL is the distance between the object side 111 of the first lens 11 and the image plane, IH is the half-image height of the infrared wide-angle lens, the focal lengths of the first lens 11 to the fifth lens 15 are f1', f2', f3', f4', and f5' respectively, f12' is the combined focal length of the first lens 11 and the second lens 12, and f345' is the combined focal length of the third lens 13, the fourth lens 14, and the fifth lens 15. Specifically, in this embodiment, the structural parameters of the infrared wide-angle lens satisfy Table 1, and the aspherical parameters satisfy Tables 2 and 3.

[0072] Table 1

[0073]

[0074]

[0075] Table 2

[0076]

[0077] Table 3

[0078]

[0079] The aforementioned infrared wide-angle lens, through the structure and parameter settings of the first lens 11, the second lens 12, the third lens 13, the fourth lens 14, and the fifth lens 15, enables the product's field of view to reach 100 degrees, greatly improving the product's field of view.

[0080] Please see Figures 5 to 8 The second embodiment of the present invention provides an infrared wide-angle lens, including a first lens 21, a second lens 22, an aperture stop, a third lens 23, a fourth lens 24, a fifth lens 25, and a filter 26 arranged sequentially from the object side to the image side along the optical axis. The object side 211 of the optical axis region of the first lens 21 is concave, and the image side 212 is concave. The object side 221 of the optical axis region of the second lens 22 is convex, and the image side 222 is concave. Specifically, in this embodiment, the structural parameters of the infrared wide-angle lens satisfy Table 4, and the aspherical parameters satisfy Tables 5 and 6.

[0081] Table 4

[0082]

[0083] Table 5

[0084]

[0085]

[0086] Table 6

[0087]

[0088] The aforementioned infrared wide-angle lens, through the structure and parameter settings of the first lens 21, the second lens 22, the third lens 23, the fourth lens 24, and the fifth lens 25, enables the product's field of view to reach 112.15 degrees, greatly improving the product's field of view.

[0089] Please see Figures 9 to 12 The third embodiment of the present invention provides an infrared wide-angle lens, including a first lens 31, a second lens 32, an aperture stop, a third lens 33, a fourth lens 34, a fifth lens 35, and a filter 36 arranged sequentially from the object side to the image side along the optical axis. The object side 311 of the optical axis region of the first lens 31 is concave, and the image side 312 is concave. The object side 321 of the optical axis region of the second lens 32 is convex, and the image side 322 is concave. Specifically, in this embodiment, the structural parameters of the infrared wide-angle lens satisfy Table 7, and the aspherical parameters satisfy Tables 8 and 9.

[0090] Table 7

[0091]

[0092]

[0093] Table 8

[0094]

[0095] Table 9

[0096]

[0097] The aforementioned infrared wide-angle lens, through the structure and parameter settings of the first lens 31, the second lens 32, the third lens 33, the fourth lens 34, and the fifth lens 35, enables the product's field of view to reach 117 degrees, greatly improving the product's field of view.

[0098] Please see Figures 13 to 16 The fourth embodiment of the present invention provides an infrared wide-angle lens, comprising a first lens 41, a second lens 42, an aperture stop, a third lens 43, a fourth lens 44, a fifth lens 45, and a filter 46 arranged sequentially from the object side to the image side along the optical axis. The object side 411 of the optical axis region of the first lens 41 is concave, and the image side 412 is concave. The object side 421 of the optical axis region of the second lens 42 is convex, and the image side 422 is concave. Specifically, in this embodiment, the structural parameters of the infrared wide-angle lens satisfy Table 10, and the aspherical parameters satisfy Tables 11 and 12.

[0099] Table 10

[0100]

[0101] Table 11

[0102]

[0103] Table 12

[0104]

[0105] The aforementioned infrared wide-angle lens, through the structure and parameter settings of the first lens 41, the second lens 42, the third lens 43, the fourth lens 44, and the fifth lens 45, enables the product's field of view to reach 91.1 degrees, greatly improving the product's field of view.

[0106] Please see Figures 17 to 20The fifth embodiment of the present invention provides an infrared wide-angle lens, comprising a first lens 51, a second lens 52, an aperture stop, a third lens 53, a fourth lens 54, a fifth lens 55, and a filter 56 arranged sequentially from the object side to the image side along the optical axis. The object side 511 of the optical axis region of the first lens 51 is concave, and the image side 512 is concave. The object side 521 of the optical axis region of the second lens 52 is convex, and the image side 522 is concave. Specifically, in this embodiment, the structural parameters of the infrared wide-angle lens satisfy Table 13, and the aspherical parameters satisfy Tables 14 and 15.

[0107] Table 13

[0108]

[0109]

[0110] Table 14

[0111]

[0112] Table 15

[0113]

[0114] The aforementioned infrared wide-angle lens, through the structure and parameter settings of the first lens 51, the second lens 52, the third lens 53, the fourth lens 54, and the fifth lens 55, enables the product's field of view to reach 117 degrees, greatly improving the product's field of view.

[0115] In one embodiment of the present invention, the refractive index of the first lens, the second lens, the third lens, and the fourth lens are all greater than 1.50, and the Abbe number is greater than 18.

[0116] In one embodiment of the present invention, the fifth lens has a refractive index greater than 1.50 and an Abbe number greater than 50.

[0117] In one embodiment of the present invention, the aperture number of the infrared wide-angle lens is greater than or equal to 1.1.

[0118] In one embodiment of the present invention, the infrared wide-angle lens also satisfies the following relationship:

[0119] 0.6 <SAG11 / SAG12<1.1;

[0120] 0.8 <SAG21 / SAG22<1.28,

[0121] -0.75 <SAG51 / SAG52<0.38;

[0122] Wherein, SAG11 is the sagitta of the object-side surface of the first lens, SAG12 is the sagitta of the image-side surface of the first lens, SAG21 is the sagitta of the object-side surface of the second lens, SAG22 is the sagitta of the image-side surface of the second lens, SAG51 is the sagitta of the object-side surface of the fifth lens, and SAG52 is the sagitta of the image-side surface of the fifth lens.

[0123] In one embodiment of the present invention, the infrared wide-angle lens also satisfies the following relationship:

[0124] 1.2 <Y11 / Y21<1.7;

[0125] 0.95 <Y11 / Y52<1.35;

[0126] Wherein, Y11 is the maximum effective radius of the object side of the first lens, Y21 is the maximum effective radius of the object side of the second lens, and Y52 is the maximum effective radius of the image side of the fifth lens.

[0127] In one embodiment of the present invention, the infrared wide-angle lens also satisfies the following relationship:

[0128] 0.08 < |R1+R2 / R1-R2| < 0.6;

[0129] 2.55 < |R3+R4 / R3-R4| < 15;

[0130] 0.25 < |R1 / R2| < 0.9;

[0131] 0.35 <R3 / R4<0.95;

[0132] Wherein, R1 is the radius of curvature of the object side of the first lens, R2 is the radius of curvature of the image side of the first lens, R3 is the radius of curvature of the object side of the second lens, and R4 is the radius of curvature of the image side of the second lens.

[0133] Furthermore, the infrared wide-angle lens also satisfies the following relationship:

[0134] 0.36≤T2 / T4≤0.65;

[0135] 1.45≤T4 / T5≤2.7;

[0136] Wherein, T2 is the center thickness of the second lens, T4 is the center thickness of the fourth lens, and T5 is the center thickness of the fifth lens.

[0137] In one embodiment of the present invention, the infrared wide-angle lens also satisfies the following relationship:

[0138] 0.05 <A1 / A2<0.1;

[0139] 12 <A3 / A4<20;

[0140] 0.04≤A4 / T5≤0.11;

[0141] Wherein, A1 is the air gap between the first lens and the second lens, A2 is the air gap between the second lens and the third lens, A3 is the air gap between the third lens and the fourth lens, A4 is the air gap between the fourth lens and the fifth lens, and T5 is the center thickness of the fifth lens.

[0142] In one embodiment of the present invention, the infrared wide-angle lens also satisfies the following relationship:

[0143] 0.17 <T12 / TTL<0.25;

[0144] 0.25 <T12 / T345<0.55;

[0145] Wherein, T12 is the combined center thickness of the first lens and the second lens, and T345 is the combined center thickness of the third lens, the fourth lens and the fifth lens.

[0146] The aforementioned infrared wide-angle lens, through the structure and parameter settings of the first, second, third, fourth, and fifth lenses, enables the product's field of view to reach 90-120 degrees, greatly improving the product's field of view.

[0147] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.

Claims

1. An infrared wide-angle lens, characterized in that, The system includes a first lens, a second lens, an aperture stop, a third lens, a fourth lens, a fifth lens, and a filter, arranged sequentially from the object side to the image side along the optical axis. The object side and image side of the first lens in the optical axis region are both concave, while the object side and image side of the second lens in the optical axis region are both convex. The infrared wide-angle lens satisfies the following relationship: f1'<0, f2'>0, f3'>0, f4'>0, f5'<0; 0.25 <IH / TTL<0.38; -1.25 <f1' / f3'<-0.6,0.2<f1' / f5'<0.5,-0.4<f' / f12'<-0.15,0.8<f' / f345'<1.5,-4<f12' / f345'<-2; Wherein, f' is the focal length of the infrared wide-angle lens, TTL is the distance between the object side of the first lens and the image plane, IH is the half image height of the infrared wide-angle lens, the focal lengths of the first lens to the fifth lens are f1', f2', f3', f4', and f5' respectively, f12' is the combined focal length of the first lens and the second lens, and f345' is the combined focal length of the third lens, the fourth lens, and the fifth lens; The refractive index of the first lens, the second lens, the third lens, and the fourth lens are all greater than 1.50, and the Abbe number is greater than 18. The fifth lens has a refractive index greater than 1.50 and an Abbe number greater than 50. The infrared wide-angle lens also satisfies the following relationship: 0.6 <SAG11 / SAG12<1.1; 0.8 <SAG21 / SAG22<1.28, -0.75 <SAG51 / SAG52<0.38; Wherein, SAG11 is the sagitta of the object-side surface of the first lens, SAG12 is the sagitta of the image-side surface of the first lens, SAG21 is the sagitta of the object-side surface of the second lens, SAG22 is the sagitta of the image-side surface of the second lens, SAG51 is the sagitta of the object-side surface of the fifth lens, and SAG52 is the sagitta of the image-side surface of the fifth lens.

2. The infrared wide-angle lens according to claim 1, characterized in that, The aperture number of the infrared wide-angle lens is greater than or equal to 1.

1.

3. The infrared wide-angle lens according to claim 1, characterized in that, The infrared wide-angle lens also satisfies the following relationship: 1.2 <Y11 / Y21<1.7; 0.95 <Y11 / Y52<1.35; Wherein, Y11 is the maximum effective radius of the object side of the first lens, Y21 is the maximum effective radius of the object side of the second lens, and Y52 is the maximum effective radius of the image side of the fifth lens.

4. The infrared wide-angle lens according to claim 1, characterized in that, The infrared wide-angle lens also satisfies the following relationship: 0.08 < |R1+R2 / R1-R2| < 0.6; 2.55 < |R3+R4 / R3-R4| < 15; 0.25 < |R1 / R2| < 0.9; 0.35 <R3 / R4<0.95; Wherein, R1 is the radius of curvature of the object side of the first lens, R2 is the radius of curvature of the image side of the first lens, R3 is the radius of curvature of the object side of the second lens, and R4 is the radius of curvature of the image side of the second lens.

5. The infrared wide-angle lens according to claim 1, characterized in that, The infrared wide-angle lens also satisfies the following relationship: 0.36≤T2 / T4≤0.65; 1.45≤T4 / T5≤2.7; Wherein, T2 is the center thickness of the second lens, T4 is the center thickness of the fourth lens, and T5 is the center thickness of the fifth lens.

6. The infrared wide-angle lens according to claim 1, characterized in that, The infrared wide-angle lens also satisfies the following relationship: 0.05 <A1 / A2<0.1; 12 <A3 / A4<20; 0.04≤A4 / T5≤0.11; Wherein, A1 is the air gap between the first lens and the second lens, A2 is the air gap between the second lens and the third lens, A3 is the air gap between the third lens and the fourth lens, A4 is the air gap between the fourth lens and the fifth lens, and T5 is the center thickness of the fifth lens.

7. The infrared wide-angle lens according to claim 1, characterized in that, The infrared wide-angle lens also satisfies the following relationship: 0.17 <T12 / TTL<0.25; 0.25 <T12 / T345<0.55; Wherein, T12 is the combined center thickness of the first lens and the second lens, and T345 is the combined center thickness of the third lens, the fourth lens and the fifth lens.

Images