Deep detection infrared wide-angle lens suitable for temperature detection in furnace

By designing a multi-lens combination deep detection infrared wide-angle lens, the problems of insufficient depth and high cost of high temperature detection of boilers are solved, and efficient and accurate 2000℃ temperature measurement and long-life detector protection are achieved, improving field angle and resolution , reducing assembly difficulty and cost.

CN119126350AActive Publication Date: 2024-12-13NANJING WAVELENGTH OPTO ELECTRONICS SCI & TECH CO LTD
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Patent Information

Application Number
CN202411030294.2
Authority / Receiving Office
CN · China
Patent Type
Applications(China)
Current Assignee / Owner
Filing Date
2024-07-30
Publication Date
2024-12-13
Estimated Expiration
2044-07-30

AI Technical Summary

Technical Problem

The existing boiler high-temperature detection lens has insufficient detection depth, large focal length, small field of view, high difficulty in group adjustment, high cost and low resolution, which cannot meet the temperature detection needs of high-temperature boilers.

Method used

A deep detection infrared wide-angle lens is designed, including multiple lens combinations, using aspherical lenses and single crystal germanium materials, reducing optical diameter and volume, increasing field of view and detection depth, suitable for high temperature environments of 2000℃, protecting Detectors reduce the difficulty and cost of grouping.

Benefits of technology

Accurate measurements up to 2000°C, detection depth exceeds 550mm and field angle of view up to 160°, reducing the volume and weight of the lens and detector, improving resolution and reliability, extending service life and reducing costs.

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Abstract

The invention discloses a deep detection infrared wide-angle lens suitable for temperature detection in a furnace. The deep detection infrared wide-angle lens comprises an attenuation piece, a first lens, a second lens, a third lens, a lens A and a lens B which are sequentially arranged from an object space to an image space, wherein the first lens is a concave-convex lens with a positive refractive index; the second lens is a convex-concave lens with a positive refractive index; the third lens is a concave-convex lens with a positive refractive index; the lens A and the lens B are convex-concave lenses with positive refractive indexes; except that the object side surface of the lens B is an aspheric surface, the object side surfaces and the image side surfaces of the other lenses are spherical surfaces. According to the invention, accurate measurement as high as 2000 DEG C can be realized, the detection depth reaches more than 550 mm, a lens and a detector can be well protected, and the influence caused by high temperature is avoided; a smaller focal length is adopted, a larger field of view is achieved, the imaging breadth is large, a smaller detector is adapted, and the reliability is high; the aperture of the whole optical lens is small, so that the cost can be saved to the greatest extent; the imaging quality is good, the transfer function reaches or approaches the diffraction limit, and the resolution precision is high.
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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] As a device that converts fuel into heat energy, boilers have long played an important role in industrial production. The temperature detection inside the furnace is the most direct reflection of whether the combustion inside the furnace is sufficient and stable. By accurately testing the temperature inside the furnace, the uniform distribution of fuel combustion can be reasonably controlled.

[0003] Different lenses have different applicable occasions and usage conditions. The temperature of the boiler can be as high as 800-2000°C, and general temperature measuring lenses cannot meet the use requirements of boiler high temperatures. There is little research on the detection of high temperatures in boilers in the prior art. 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, 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 is 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, and the overall volume and weight are significantly reduced, so the cost advantage is 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 refractive power concave-convex lens; the second lens is a positive refractive power convex-concave lens; the third lens is a positive refractive power concave-convex lens; both the lens A and the lens B are positive refractive power convex-concave lenses; except that the object side surface of the lens B is aspherical, the object side surfaces and the image side surfaces of the other lenses are spherical.

[0007] The total length of the above lens is about 120mm. The above lens only uses one aspherical surface, which greatly reduces 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 arranged in sequence from the object side to the image side; wherein the first lens is a positive refractive power convex-concave lens; the second lens is a positive refractive power convex-concave lens; the third lens, the fourth lens and the fifth lens are all positive refractive power convex-concave lenses; the sixth lens is a positive refractive power convex-concave lens; the seventh lens is a positive refractive power convex-concave lens, and the lens A and the lens B are both positive refractive power convex-concave lenses.

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

[0010] Since the mouth 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 failure of the detector. For this reason, this application specially designs this extended version. This extended version has the lens extended into the chamber, and the detector is outside the cavity, which can effectively protect the detector and improve measurement safety.

[0011] The attenuation sheet of the present 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 suitable for detectors 384*288-17um; and the detection depth is more than 550mm.

[0013] The above lens is applicable to the wavelength band of 8-14μm; the diagonal imaging surface is 8.16mm. The horizontal field of view angle is 120°, the vertical field of view angle is 90°, and the diagonal field of view angle is 160°. This application uses a smaller focal length, has a larger field of view, and is suitable for a smaller detector. The overall volume and weight are significantly reduced, and the cost advantage is relatively obvious.

[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 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. This can effectively correct aberrations and improve imaging quality.

[0015] In order to further ensure the imaging effect, 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 -70.005±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, and the radius of curvature of the fifth image 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 the 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 the imaging quality, the center interval between the first lens and the second lens is 0.2±0.005mm, the center interval between the second lens and the third lens is 40±0.005mm, the center interval between the third lens and the fourth lens is 136.6±0.005mm, and the center interval between the fourth lens and the fifth lens is 147.37±0.005mm; the center interval between the fifth lens and the sixth lens is 208.57±0.005mm, the center interval between the sixth lens and the seventh lens is 103.955±0.005mm, the center interval between the seventh lens and lens A is 88.23±0.005mm, the center interval between lens A and lens B is 8.42±0.005mm, and the center interval 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 imaging 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 take into account both 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 installation 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 the present 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 the detection depth is more than 550mm. It can well protect the lens and detector, avoid the influence of high temperature and extend the service life;

[0027] 2) It adopts a smaller focal length, has a larger field of view, and the field of view angle can reach 160°. It has a large imaging format and is suitable for smaller detectors. It can be used for 384X288 movement, and the pixel 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 aperture, which can save costs to the greatest extent;

[0029] 4) It adopts a straight-tube three-dimensional 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 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 8-14um and 30lp / mm;

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

[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 8-14um;

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

[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 A magnified image of

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

[0040] Fig. 9 This is a light spot diagram of the deep detection infrared wide-angle lens suitable for furnace temperature detection in Example 2 at 8-14um;

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

[0042] Fig.11 This is a relative illumination diagram of the deep-detection infrared wide-angle lens suitable for furnace temperature detection in Example 2 at 8-14um; DETAILED DESCRIPTION

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

[0044] Example 1

[0045] like Figure 1 As shown, this example is suitable for a deep detection infrared wide-angle lens (short tube lens) for furnace temperature detection, including an attenuation plate, a first lens L1, a second lens L2, a third lens L3, a lens A L8 and a lens B L9 which are arranged in sequence from the object side to the image side; wherein the first lens is a positive refractive power convex-concave lens; and the second lens is a positive refractive power convex-concave lens.

[0046] Compared with Example 2, the intermediate transfer lenses, namely the fourth lens L4, the fifth lens L5, the sixth lens L6 and the seventh lens L7, are removed in this example.

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

[0048] The first lens L1 to lens B are all made of single crystal germanium, which has high friction resistance, hardness and chemical stability, and can effectively protect the internal optical lens group; the refractive index is as high as 4.0 or more in the range of 8um to 10um, and aspherical surfaces can be used, which helps to correct the aberration of the optical system; it has high transmittance and is resistant to high-intensity radiation, and is easy to process;

[0049] A 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] Aspheric equations used in Table 2:

[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 surface coefficients not mentioned in the above table or those that are blank have a value of 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, defocus 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 of 30 line pairs is required to be achieved with the 384x288 17μm detector. 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 0.15lp / mm at the edge in the existing patent; 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 larger the defocus range, the easier it is 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 comprises 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 BL9 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 the lens A and the lens B are both positive convex-concave lenses.

[0068] Embodiment From the object side to the image side, the two sides of the first lens L1 are the first object-side surface S1 and the first image-side surface S2, the two sides of the second lens L2 are the second object-side surface S3 and the second image-side surface S4, the two sides of the third lens L3 are the third object-side surface S5 and the third image-side surface S6, the two sides of the fourth lens L4 are the fourth object-side surface S7 and the fourth image-side surface S8, the two sides of the fifth lens L5 are the fifth object-side surface S9 and the fifth image-side surface S10; the two sides of the sixth lens L6 are the sixth object-side surface S11 and the sixth image-side surface S12; the two sides of the seventh lens L7 are the seventh object-side surface S13 and the seventh image-side surface S14; the two sides of the lens AL8 are the eighth object-side surface S15 and the eighth image-side surface S16; the two sides of the 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] The first lens L1 to lens B are all made of single crystal germanium, which has high friction resistance, hardness and chemical stability, and can effectively protect the internal optical lens group; the refractive index is as high as 4.0 or more in the range of 8um to 10um, and aspherical surfaces can be used, which helps to correct the aberration of the optical system; it has high transmittance and is resistant to high-intensity radiation, and is easy to process;

[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] Aspheric equations used in Table 4:

[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 surface coefficients not mentioned in the above table or those that are blank have a value of 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, defocus 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 of 30 line pairs is required to be achieved with the 384x288 17μm detector. 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 excellent; Fig. 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; Fig.10 It can be seen that the defocus range of the system is -0.2mm to +0.2mm. The larger the defocus range, the easier it is to focus the detector. Fig.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 in that: The invention 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 meniscus lens with a positive refractive power; the second lens is a meniscus lens with a positive refractive power; the third lens is a meniscus lens with a positive refractive power; both the lens A and the lens B are meniscus lenses with a positive refractive power; except that the object side surface of the lens B is an aspherical surface, the object side surfaces and the image side surfaces of the other lenses are all spherical surfaces.

2. A deep-detection infrared wide-angle lens suitable for furnace temperature detection, characterized in that: The invention comprises 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 the lens A and the lens B are all positive convex-concave lenses.

3. The deep-detection infrared wide-angle lens suitable for furnace temperature detection as claimed in claim 1 or 2, characterized in that: The focal length f' is 3.3mm, the field of view is 160°; the compatible detector is 384*288-17um; the detection depth is over 550mm.

4. The deep-detection infrared wide-angle lens suitable for furnace temperature detection as claimed in 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.

5. The deep-detection infrared wide-angle lens suitable for furnace temperature detection as claimed in claim 1 or 2, 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 surface is 97.20±0.005mm; the radius of curvature of the sixth object side surface is 58.865±0.005mm, and the radius of curvature of the sixth image side surface is 55.204±0.005mm; the radius of curvature of the seventh object side surface is 49.493±0.005mm, and the radius of curvature of the seventh image side surface is 47.475±0.005mm; the radius of curvature of the eighth object side surface is 17.58±0.005mm, and the radius of curvature of the eighth image side surface is 20.115±0.005mm; the radius of curvature of the ninth object side surface is 15.014±0.005mm, and the radius of curvature of the ninth image side surface is 14.85±0.005mm.

6. The deep-detection infrared wide-angle lens suitable for furnace temperature detection as claimed in claim 1, 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 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.

7. The deep-detection infrared wide-angle lens suitable for furnace temperature detection as claimed in claim 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.

8. The deep-detection infrared wide-angle lens suitable for furnace temperature detection as claimed in claim 1 or 2, characterized in that: The aperture is located on the object side of the eighth plane; all lenses are made of single crystal germanium.

9. The deep-detection infrared wide-angle lens suitable for furnace temperature detection as claimed in 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.

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

Citation Information

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