Deep-probe infrared wide-angle lens suitable for detecting temperature in furnace

Abstract

The application discloses a deep-probing infrared wide-angle lens suitable for detecting the temperature in a furnace, which comprises, from the object side to the image side, an attenuation sheet, a first lens, a second lens, a third lens, a lens A and a lens B; wherein the first lens is a concave-convex lens with positive refractive power; the second lens is a convex-concave lens with positive refractive power; the third lens is a concave-convex lens with positive refractive power; the lens A and the lens B are both convex-concave lenses with positive refractive power; and the object side surface and the image side surface of the rest lenses are all spherical surfaces, with the exception that the object side surface of the lens B is an aspherical surface. The application can realize accurate measurement up to 2000 DEG C, the detection depth reaches more than 550 mm, can well protect the lens and the detector, and avoid the influence caused by high temperature; the smaller focal length is adopted, the larger field of view is obtained, the imaging width is large, a smaller detector is adapted, and the reliability is high; the aperture of the whole optical lens is small, and the cost can be saved to the maximum extent; the imaging quality is good, the transfer function reaches or approaches the diffraction limit, and the resolution accuracy is high.

Description

Technical Field

[0001] The invention relates to a deep-detection infrared wide-angle lens suitable for detecting temperature in a furnace, and belongs to the technical field of temperature measurement in boilers. Background Art

[0002] Boilers, as devices that convert fuel into heat energy, have long played a vital role in industrial production. Measuring the furnace's temperature is the most direct indicator of sufficient and stable combustion. Accurately measuring the furnace's temperature allows for the proper control of the even distribution of fuel combustion.

[0003] Different lenses have different applicable occasions and usage conditions. The temperature of a boiler can be as high as 800-2000°C, and general temperature measuring lenses cannot meet the requirements of high-temperature use of boilers. There is little research on the detection of high-temperature boilers in the existing technology. Patent application number 202210685429.3 discloses a wide-angle infrared lens for boilers. Although this lens can be used for boiler temperature measurement at 1500°C to 2000°C, the detection depth is less than 100mm; and the focal length is large and the field of view is small, with a horizontal field of view angle of 84.4° and a vertical field of view angle of 72°; at the same time, the assembly adjustment is difficult and the cost is high; the resolution also needs to be improved. Summary of the Invention

[0004] The present invention provides a deep-detection infrared wide-angle lens suitable for furnace temperature detection. The lens can be used for furnace temperature detection at different high temperatures and is suitable for temperature detection of power generation boilers, industrial boilers, production boilers, etc., and can achieve accurate measurement up to 2000°C. The detection depth reaches more than 550mm, which can well protect the lens and detector, avoid the influence of high temperature, and extend the service life. The lens has a focal length of 3.3mm and a field of view of 160°, which is suitable for smaller detectors. The overall volume and weight are significantly reduced, and the cost advantage is relatively obvious. The lens is easy to assemble and has high resolution.

[0005] In order to solve the above technical problems, the technical solutions adopted by the present invention are as follows:

[0006] A deep-detection infrared wide-angle lens suitable for furnace temperature detection comprises an attenuation plate, a first lens, a second lens, a third lens, a lens A, and a lens B, which are arranged in sequence from the object side to the image side; wherein the first lens is a positive meniscus lens; the second lens is a positive meniscus lens; the third lens is a positive meniscus lens; both lenses A and B are positive meniscus lenses; except for the object side surface of lens B which is aspherical, the object side surfaces and image side surfaces of the other lenses are all spherical.

[0007] The total length of the above lenses is approximately 120mm. These lenses use only one aspherical surface, significantly reducing the difficulty of assembly and adjustment.

[0008] In order to further improve safety, a deep-detection infrared wide-angle lens suitable for furnace temperature detection includes an attenuation plate, a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, a lens A, and a lens B, which are arranged in sequence from the object side to the image side; wherein the first lens is a positive convex-concave lens; the second lens is a positive convex-concave lens; the third lens, the fourth lens, and the fifth lens are all positive convex-concave lenses; the sixth lens is a positive convex-concave lens; the seventh lens is a positive convex-concave lens; and both lens A and lens B are positive convex-concave lenses.

[0009] The total length of the above lenses is about 800mm.

[0010] Since the opening of some furnace cavities is relatively narrow and the chamber is relatively large, the short lens needs to extend the lens and the detector into the chamber together. The high temperature can easily cause damage or malfunction of the detector. For this reason, this application specially designs this extended version. This extended version allows the lens to be extended into the chamber, while the detector is outside the cavity, which can effectively protect the detector and improve measurement safety.

[0011] The attenuation sheet of this application is a flat lens.

[0012] The above-mentioned deep-detection infrared wide-angle lens suitable for furnace temperature detection has a focal length f' of 3.3mm and a field of view of 160°; it is compatible with the detector 384*288-17um; and the detection depth reaches more than 550mm.

[0013] The above lens is suitable for wavelengths between 8 and 14 μm, with a diagonal imaging area of ​​8.16 mm. Its horizontal field of view is 120°, its vertical field of view is 90°, and its diagonal field of view is 160°. This application utilizes a smaller focal length, resulting in a larger field of view and adaptability to smaller detectors. This significantly reduces overall size and weight, resulting in significant cost advantages.

[0014] From the object side to the image side, the two sides of the first lens are the first object side surface and the first image side surface, the two sides of the second lens are the second object side surface and the second image side surface, the two sides of the third lens are the third object side surface and the third image side surface, the two sides of the fourth lens are the fourth object side surface and the fourth image side surface, the two sides of the fifth lens are the fifth object side surface and the fifth image side surface; the two sides of the sixth lens are the sixth object side surface and the sixth image side surface; the two sides of the seventh lens are the seventh object side surface and the seventh image side surface; the two sides of lens A are the eighth object side surface and the eighth image side surface; the two sides of lens B are the ninth object side surface and the ninth image side surface; the fourth object side surface, the fifth object side surface, the sixth object side surface, the sixth image side surface, the seventh object side surface and the ninth image side surface are all aspherical surfaces; the first object side surface, the first image side surface, the second object side surface, the second image side surface, the third object side surface, the third image side surface, the fourth image side surface, the fifth image side surface, the seventh image side surface, the eighth object side surface, the eighth image side surface and the ninth image side surface are all spherical lenses. This can effectively correct aberrations and improve imaging quality.

[0015] To further ensure the imaging effect, the curvature radius of the first object side surface is -13.829±0.005mm, and the curvature radius of the first image side surface is -13.614±0.005mm; the curvature radius of the second object side surface is 34.51±0.005mm, and the curvature radius of the second image side surface is 109.27±0.005mm; the curvature radius of the third object side surface is -112.24±0.005mm, and the curvature radius of the third image side surface is -70.005±0.005mm; the curvature radius of the fourth object side surface is 104.96±0.005mm, and the curvature radius of the fourth image side surface is 101.57±0.005mm; the curvature radius of the fifth object side surface is 106.89±0.005mm. ±0.005mm, the radius of curvature of the fifth image side is 97.20±0.005mm; the radius of curvature of the sixth object side is 58.865±0.005mm, and the radius of curvature of the sixth image side is 55.204±0.005mm; the radius of curvature of the seventh object side is 49.493±0.005mm, and the radius of curvature of the seventh image side is 47.475±0.005mm; the radius of curvature of the eighth object side is 17.58±0.005mm, and the radius of curvature of the eighth image side is 20.115±0.005mm; the radius of curvature of the ninth object side is 15.014±0.005mm, and the radius of curvature of the ninth image side is 14.85±0.005mm.

[0016] To further ensure imaging quality, the center distance between the first lens and the second lens is 0.2±0.005mm, the center distance between the second lens and the third lens is 40±0.005mm, the center distance between the third lens and lens A is 40±0.005mm, the center distance between lens A and lens B is 8.42±0.005mm, and the center distance from lens B to the image plane is 13.186±0.005mm.

[0017] To further ensure imaging quality, the center distance between the first lens and the second lens is 0.2±0.005mm, the center distance between the second lens and the third lens is 40±0.005mm, the center distance between the third lens and the fourth lens is 136.6±0.005mm, and the center distance between the fourth lens and the fifth lens is 147.37±0.005mm; the center distance between the fifth lens and the sixth lens is 208.57±0.005mm, the center distance between the sixth lens and the seventh lens is 103.955±0.005mm, the center distance between the seventh lens and lens A is 88.23±0.005mm, the center distance between lens A and lens B is 8.42±0.005mm, and the center distance from lens B to the image plane is 11.46±0.005mm.

[0018] The aperture of the deep-detection infrared wide-angle lens suitable for furnace temperature detection is located on the object side of the eighth surface.

[0019] To ensure stability and durability, all lenses are made of single-crystal germanium.

[0020] To further ensure imaging stability and quality, the center thickness of the first lens is 4.800±0.05mm, the center thickness of the second lens is 3.500±0.05mm, the center thickness of the third lens is 4.000±0.05mm, the center thickness of the fourth lens is 7.800±0.05mm, the center thickness of the fifth lens is 8.800±0.05mm, the center thickness of the sixth lens is 8.670±0.05mm, the center thickness of the seventh lens is 10.00±0.05mm, the center thickness of lens A is 2.500±0.05mm, and the center thickness of lens B is 2.000±0.05mm.

[0021] In order to balance imaging quality and lens volume, the outer diameter of the first lens is 12.00~18.00mm, the outer diameter of the second lens is 24.00~22.00mm, the outer diameter of the third lens is 37.00~39.00mm, the outer diameter of the fourth lens is 38.00~41.00mm, the outer diameter of the fifth lens is 38.00~42.00mm, the outer diameter of the sixth lens is 40.00~34.00mm, the outer diameter of the seventh lens is 36.00~41.00mm, the outer diameter of lens A is 18.00~16.00mm, and the outer diameter of lens B is 15.00~12.00mm.

[0022] The above lens is an uncooled lens suitable for the long-wave detector 384*288-17um movement.

[0023] In order to ensure the conjugation of the image and the difficulty of subsequent assembly and adjustment, this application adopts three-stage imaging, which greatly reduces the optical aperture. The above-mentioned wide-angle lens suitable for temperature measurement in the furnace has a system combined focal length f' of 3.3mm, a diagonal imaging surface of 8.16mm, and a diagonal field of view of 160°.

[0024] The technologies not mentioned in this invention are all referred to the prior art.

[0025] The present invention is applicable to the wide-angle infrared lens for measuring temperature in the furnace, and has the following beneficial effects:

[0026] 1) It can achieve accurate measurement up to 2000℃ and a detection depth of more than 550mm. It can well protect the lens and detector, avoid the impact of high temperature and extend the service life;

[0027] 2) It adopts a smaller focal length, has a larger field of view, and can reach a field of view of 160°. It has a large imaging format and is suitable for smaller detectors. It can be used for 384X288 movement, and the pixel size can reach 17um. The overall volume and weight are significantly reduced, the cost advantage is relatively obvious, and the reliability is high;

[0028] 3) The overall optical lens has a small diameter, which can save costs to the greatest extent;

[0029] 4) It adopts a straight-tube tertiary imaging system configuration, with all components arranged on the same optical axis. It has the characteristics of compact structure, good adaptability, good imaging quality, and a transfer function that reaches or approaches the diffraction limit. The resolution accuracy reaches 0.4@30lp / mm at the center and 0.3@30lp / mm at the edge; the defocus range is -0.2mm to +0.2mm, and the relative illumination is above 0.91. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1-5 1 is a related view of a deep-detection infrared wide-angle lens (short-tube lens) suitable for furnace temperature detection in Example 1 of the present invention;

[0031] Figure 1 Schematic diagram of the optical path of the deep-detection infrared wide-angle lens suitable for furnace temperature detection in Example 1;

[0032] Figure 2 This is a graph of the optical transfer function of the deep-detection infrared wide-angle lens suitable for furnace temperature detection in Example 1 at 8-14 μm and 30 lp / mm;

[0033] Figure 3 This is a diagram of light spots at 8-14 μm using a deep-detection infrared wide-angle lens suitable for furnace temperature detection in Example 1;

[0034] Figure 4 This is the defocus MTF diagram of the deep-detection infrared wide-angle lens suitable for furnace temperature detection in Example 1 at 8-14 μm;

[0035] Figure 5 This is a relative illumination diagram at 8-14 μm for a deep-detection infrared wide-angle lens suitable for furnace temperature detection in Example 1;

[0036] Figure 6-11 1 is a related view of a deep-detection infrared wide-angle lens (telephoto lens) suitable for furnace temperature detection in Example 2 of the present invention;

[0037] Figure 6 Schematic diagram of the optical path of the deep-detection infrared wide-angle lens suitable for furnace temperature detection in Example 2;

[0038] Figure 7 yes Figure 6 Magnified image of;

[0039] Figure 8 This is a graph of the optical transfer function of a deep-detection infrared wide-angle lens suitable for furnace temperature detection in Example 2 at 8-14 μm and 30 lp / mm;

[0040] Figure 9 This is a diagram of light spots at 8-14 μm using a deep-detection infrared wide-angle lens suitable for furnace temperature detection in Example 2;

[0041] Figure 10 This is the defocus MTF diagram of the deep-detection infrared wide-angle lens suitable for furnace temperature detection in Example 2 at 8-14 μm;

[0042] Figure 11 This is a relative illumination diagram at 8-14 μm using a deep-probe infrared wide-angle lens suitable for furnace temperature detection in Example 2; DETAILED DESCRIPTION

[0043] In order to better understand the present invention, the content of the present invention is further illustrated below in conjunction with the examples, but the content of the present invention is not limited to the following examples.

[0044] Example 1

[0045] like Figure 1 As shown in FIG. 1 , a deep-detection infrared wide-angle lens (short-tube lens) suitable for furnace temperature detection includes, in order from the object side to the image side, an attenuation plate, a first lens L1, a second lens L2, a third lens L3, lenses A to L8, and lenses B to L9; wherein the first lens is a positive meniscus lens; and the second lens is a positive meniscus lens.

[0046] Compared with Example 2, this example removes the intermediate transfer lens L4, the fifth lens L5, the sixth lens L6 and the seventh lens L7.

[0047] From the object side to the image side, the two sides of the first lens are sequentially the first object-side surface S1 and the first image-side surface S2; the two sides of the second lens are sequentially the second object-side surface S3 and the second image-side surface S4; the two sides of the third lens are sequentially the second image-side surface S5 and the third image-side surface S6; the two sides of lens A are sequentially the eighth object-side surface S15 and the eighth image-side surface S16; the two sides of lens B are sequentially the ninth object-side surface S17 and the ninth image-side surface S18; the ninth object-side surface is aspherical; the first object-side surface, first image-side surface, second object-side surface, second image-side surface, third object-side surface, third image-side surface, eighth object-side surface, eighth image-side surface, and ninth image-side surface are all spherical lenses. The aperture is located on the object-side surface of the eighth lens.

[0048] Lenses L1 through B are all made of single-crystal germanium, which offers high friction resistance, hardness, and chemical stability, effectively protecting the internal optical system. The refractive index is as high as 4.0 or higher in the 8µm to 10µm range, and aspheric surfaces can be used to help correct aberrations in the optical system. The lens also boasts high transmittance, high-intensity radiation resistance, and easy molding and processing.

[0049] The secondary imaging method is adopted between the second image side surface S4 and the second image side surface S5, which greatly reduces the aperture of the optical element and reduces the volume and weight.

[0050] Table 1 Technical parameters of the optical system of this embodiment

[0051] focal length 3.3 Band 8-14um F# 1.5 Field of view (H)120°*(V)90°*(D)160° Detector specifications 384*288-17um

[0052] Table 2 Specific parameters of this embodiment

[0053]

[0054] The aspheric equations used in Table 2 are:

[0055]

[0056] The meanings of each quantity are as follows:

[0057] ZA: lens sagittal height of the aspheric surface along the optical axis;

[0058] R: The radius of curvature at the intersection of the surface and the optical axis; Y: The semi-aperture of the lens perpendicular to the optical axis;

[0059] k: cone coefficient;

[0060] A, B, C, D, E surface coefficients; see Table 3 for specific coefficients.

[0061] Table 3

[0062]

[0063]

[0064] The area coefficients not mentioned in the above table or those that are blank have the value 0.

[0065] The deep-detection infrared wide-angle lens for the above-mentioned furnace temperature detection can achieve accurate measurement up to 2000°C. Figures 2 to 5 The optical transfer function curve, spot diagram, through-focus MTF diagram, and relative illumination diagram of the embodiment at a temperature of +20° represent the comprehensive resolution level of the optical system and the resolution of the image. The resolution required for the 384x288 17μm detector is 30 line pairs. Figure 2 It can be seen that the optical transfer function of the system is close to the diffraction limit level, and the image resolution and contrast effect will be very good; the resolution accuracy reaches 0.4@30lp / mm at the center and 0.3@30lp / mm at the edge, which is a significant improvement compared to the existing patent's edge of 0.15lp / mm; Figure 3 It can be seen that the system's diffuse spot is within the diffraction diffuse spot, and the system has a stronger ability to identify subtle objects; Figure 4 It can be seen that the defocus range of the system is -0.2mm to +0.2mm. The large defocus range makes it easier to focus the detector. Figure 5 It can be seen that when the relative illumination of the system is above 0.93, the grayscale error at the center and edge of the image can be greatly reduced, and the occurrence of the system pot lid effect can be reduced.

[0066] Example 2

[0067] like Figure 6 and Figure 7The deep-detection infrared wide-angle lens (telephoto lens) suitable for furnace temperature detection shown in the figure includes an attenuation plate, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, a seventh lens L7, a lens AL8, and a lens B L9, which are arranged in sequence from the object side to the image side. Among them, the first lens is a positive meniscus lens; the second lens is a positive meniscus lens; the third lens, the fourth lens, and the fifth lens are all positive meniscus lenses; the sixth lens is a positive meniscus lens; the seventh lens is a positive meniscus lens; and both lens A and lens B are positive meniscus lenses.

[0068] In the embodiment, from the object side to the image side, the two surfaces of the first lens L1 are the first object-side surface S1 and the first image-side surface S2, the two surfaces of the second lens L2 are the second object-side surface S3 and the second image-side surface S4, the two surfaces of the third lens L3 are the third object-side surface S5 and the third image-side surface S6, the two surfaces of the fourth lens L4 are the fourth object-side surface S7 and the fourth image-side surface S8, the two surfaces of the fifth lens L5 are the fifth object-side surface S9 and the fifth image-side surface S10; the two surfaces of the sixth lens L6 are the sixth object-side surface S11 and the sixth image-side surface S12; the two surfaces of the seventh lens L7 are the seventh object-side surface S13 and the seventh image-side surface S14; the two surfaces of lens AL8 are the eighth object-side surface S15 and the eighth image-side surface S16; lens B The two sides of L9 are respectively the ninth object side surface S17 and the ninth image side surface S18; the fourth object side surface, the fifth object side surface, the sixth object side surface, the sixth image side surface, the seventh object side surface and the ninth object side surface are all aspherical surfaces; the first object side surface, the first image side surface, the second object side surface, the second image side surface, the third object side surface, the third image side surface, the fourth image side surface, the fifth image side surface, the seventh image side surface, the eighth object side surface, the eighth image side surface and the ninth image side surface are all spherical lenses.

[0069] Lenses L1 through B are all made of single-crystal germanium, which offers high friction resistance, hardness, and chemical stability, effectively protecting the internal optical system. The refractive index is as high as 4.0 or higher in the 8µm to 10µm range, and aspheric surfaces can be used to help correct aberrations in the optical system. The lens also boasts high transmittance, high-intensity radiation resistance, and easy molding and processing.

[0070] A secondary imaging method is adopted between the second image-side surface S4 and the third object-side surface S5, and between the sixth image-side surface S12 and the seventh object-side surface S13, which greatly reduces the aperture of the optical element and reduces the volume and weight.

[0071] Table 3 Technical parameters of the optical system of this embodiment

[0072] focal length 3.3 Band 8-14um F# 2.0 Field of view (H)120°*(V)90°*(D)160° Detector specifications 384*288-17um

[0073] Table 4 Specific parameters of this embodiment

[0074]

[0075]

[0076] The aspheric equations used in Table 4 are:

[0077]

[0078] The meanings of each quantity are as follows:

[0079] ZA: lens sagittal height of the aspheric surface along the optical axis;

[0080] R: radius of curvature at the intersection of the surface and the optical axis;

[0081] Y: semi-aperture of the lens perpendicular to the optical axis;

[0082] k: cone coefficient;

[0083] A, B, C, D, E surface coefficients; see Table 3 for specific coefficients.

[0084] Table 3

[0085]

[0086] The area coefficients not mentioned in the above table or those that are blank have the value 0.

[0087] The deep-detection infrared wide-angle lens for furnace temperature detection can achieve accurate measurement up to 2000°C; the detection depth (the depth that can be penetrated into the furnace) exceeds 550mm, which is a significant improvement compared to the existing patent's detection depth of less than 100mm. Figures 8 to 11 The optical transfer function curve, spot diagram, through-focus MTF diagram, and relative illumination diagram of the embodiment at a temperature of +20° represent the comprehensive resolution level of the optical system and the resolution of the image. The resolution required for the 384x288 17μm detector is 30 line pairs. Figure 8 It can be seen that the optical transfer function of the system is close to the diffraction limit level, and the image resolution and contrast effect will be very good; Figure 9 It can be seen that the system's diffuse spot is within the diffraction diffuse spot, and the system has a stronger ability to identify subtle objects; Figure 10 It can be seen that the defocus range of the system is -0.2mm to +0.2mm. The large defocus range makes it easier to focus the detector. Figure 11 It can be seen that when the relative illumination of the system is above 0.91, the grayscale error at the center and edge of the image can be greatly reduced, and the occurrence of the system pot lid effect can be reduced.

Claims

1. A deep-detection infrared wide-angle lens suitable for furnace temperature detection, characterized by: The lens is composed of an attenuation plate, a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, a lens A, and a lens B, which are arranged in order from the object side to the image side. The first lens is a positive meniscus lens; the second lens is a positive meniscus lens; the third lens, the fourth lens, and the fifth lens are all positive meniscus lenses; the sixth lens is a positive meniscus lens; the seventh lens is a positive meniscus lens; and both lenses A and B are positive meniscus lenses. The deep-detection infrared wide-angle lens suitable for furnace temperature detection can achieve accurate measurement up to 2000°C, with a detection depth of more than 550mm and a field of view of 160°.

2. The deep-detection infrared wide-angle lens suitable for furnace temperature detection according to claim 1, characterized in that: The focal length f' is 3.3mm; the compatible detector is 384*288-17um.

3. The deep-detection infrared wide-angle lens suitable for furnace temperature detection according to claim 1 or 2, characterized in that: From the object side to the image side, the two sides of the first lens are the first object side surface and the first image side surface, the two sides of the second lens are the second object side surface and the second image side surface, the two sides of the third lens are the third object side surface and the third image side surface, the two sides of the fourth lens are the fourth object side surface and the fourth image side surface, the two sides of the fifth lens are the fifth object side surface and the fifth image side surface; the two sides of the sixth lens are the sixth object side surface and the sixth image side surface; the two sides of the seventh lens are the seventh object side surface and the seventh image side surface; the two sides of lens A are the eighth object side surface and the eighth image side surface; the two sides of lens B are the ninth object side surface and the ninth image side surface; the fourth object side surface, the fifth object side surface, the sixth object side surface, the sixth image side surface, the seventh object side surface and the ninth object side surface are all aspherical surfaces; the first object side surface, the first image side surface, the second object side surface, the second image side surface, the third object side surface, the third image side surface, the fourth image side surface, the fifth image side surface, the seventh image side surface, the eighth object side surface, the eighth image side surface and the ninth image side surface are all spherical lenses.

4. The deep-detection infrared wide-angle lens suitable for furnace temperature detection according to claim 3, characterized in that: The radius of curvature of the first object side surface is -13.829±0.005mm, and the radius of curvature of the first image side surface is -13.614±0.005mm; the radius of curvature of the second object side surface is 34.51±0.005mm, and the radius of curvature of the second image side surface is 109.27±0.005mm; the radius of curvature of the third object side surface is -112.24±0.005mm, and the radius of curvature of the third image side surface is -70±0.005mm; the radius of curvature of the fourth object side surface is 104.96±0.005mm, and the radius of curvature of the fourth image side surface is 101.57±0.005mm; the radius of curvature of the fifth object side surface is 106.89±0.005mm , the radius of curvature of the fifth image side is 97.20±0.005mm; the radius of curvature of the sixth object side is 58.865±0.005mm, and the radius of curvature of the sixth image side is 55.204±0.005mm; the radius of curvature of the seventh object side is 49.493±0.005mm, and the radius of curvature of the seventh image side is 47.475±0.005mm; the radius of curvature of the eighth object side is 17.58±0.005mm, and the radius of curvature of the eighth image side is 20.115±0.005mm; the radius of curvature of the ninth object side is 15.014±0.005mm, and the radius of curvature of the ninth image side is 14.85±0.005mm.

5. The deep-detection infrared wide-angle lens suitable for furnace temperature detection according to claim 1 or 2, characterized in that: The center distance between the first lens and the second lens is 0.2±0.005mm, the center distance between the second lens and the third lens is 40±0.005mm, the center distance between the third lens and the fourth lens is 136.6±0.005mm, and the center distance between the fourth lens and the fifth lens is 147.37±0.005mm; the center distance between the fifth lens and the sixth lens is 208.57±0.005mm, the center distance between the sixth lens and the seventh lens is 103.955±0.005mm, the center distance between the seventh lens and lens A is 88.23±0.005mm, the center distance between lens A and lens B is 8.42±0.005mm, and the center distance from lens B to the image plane is 11.46±0.005mm.

6. The deep-detection infrared wide-angle lens suitable for furnace temperature detection according to claim 3, characterized in that: The aperture is located on the eighth objective side; all lenses are made of single crystal germanium.

7. The deep-detection infrared wide-angle lens suitable for furnace temperature detection according to claim 1 or 2, characterized in that: The center thickness of the first lens is 4.800±0.05mm, the center thickness of the second lens is 3.500±0.05mm, the center thickness of the third lens is 4.000±0.05mm, the center thickness of the fourth lens is 7.800±0.05mm, the center thickness of the fifth lens is 8.800±0.05mm, the center thickness of the sixth lens is 8.670±0.05mm, the center thickness of the seventh lens is 10.00±0.05mm, the center thickness of lens A is 2.500±0.05mm, and the center thickness of lens B is 2.000±0.05mm.

8. The deep-detection infrared wide-angle lens suitable for furnace temperature detection according to claim 1 or 2, characterized in that: The outer diameter of the first lens is 12.00~18.00mm, the outer diameter of the second lens is 24.00~22.00mm, the outer diameter of the third lens is 37.00~39.00mm, the outer diameter of the fourth lens is 38.00~41.00mm, the outer diameter of the fifth lens is 38.00~42.00mm, the outer diameter of the sixth lens is 40.00~34.00mm, the outer diameter of the seventh lens is 36.00~41.00mm, the outer diameter of lens A is 18.00~16.00mm, and the outer diameter of lens B is 15.00~12.00mm.

Images