A variable-focus infrared lens suitable for a wide temperature field

Abstract

This invention discloses a variable-focus infrared lens suitable for a wide temperature field, comprising: an infrared lens base, an infrared dichroic filter assembly, a front infrared lens assembly, a rear infrared lens assembly, an infrared zoom lens assembly, and an infrared filter switching assembly; wherein the infrared dichroic filter assembly, the front infrared lens assembly, the rear infrared lens assembly, the infrared zoom lens assembly, and the infrared filter switching assembly are all fixed to the upper surface of the infrared lens base; the optical axes of the front infrared lens assembly, the rear infrared lens assembly, the infrared zoom lens assembly, and the infrared filter switching assembly are all aligned. This invention effectively improves the environmental adaptability and target acquisition capability of laser optical systems.

Description

Technical Field

[0001] This invention belongs to the field of laser optics technology, and particularly relates to a variable-focus infrared lens suitable for a wide temperature field. Background Technology

[0002] Infrared lenses are a key component of laser optics technology, directly determining the performance and imaging quality of laser optical systems. As the application range of laser optical systems continues to expand, the operating environments of infrared lenses are becoming increasingly harsh. Therefore, even in harsh environments with wide temperature fields, infrared lenses can still capture the infrared characteristics of target objects for laser emitting devices, while also enabling zoom functionality to track target objects at different distances and continuously acquire high-quality images. This is both the key and the challenge in the design of infrared lenses.

[0003] However, current infrared lenses have a narrow operating temperature range, generally only usable in low or high temperature environments. This limited range severely restricts their application scenarios. Furthermore, existing infrared lenses typically have a fixed focal length, enabling high-quality imaging only within a specific distance range. When the tracked target object exceeds a certain distance, the image quality degrades significantly, severely impacting the lens's capture performance. Summary of the Invention

[0004] The technical problem solved by this invention is to overcome the shortcomings of the prior art and provide a variable focal length infrared lens lens suitable for a wide temperature field, which effectively improves the environmental adaptability and target acquisition capability of laser optical systems.

[0005] The objective of this invention is achieved through the following technical solution: a variable-focus infrared lens suitable for a wide temperature field, comprising: an infrared lens base, an infrared dichroic filter assembly, a front infrared lens assembly, a rear infrared lens assembly, an infrared zoom lens assembly, and an infrared filter switching assembly; wherein, the infrared dichroic filter assembly, the front infrared lens assembly, the rear infrared lens assembly, the infrared zoom lens assembly, and the infrared filter switching assembly are all fixed on the upper surface of the infrared lens base; the optical axes of the front infrared lens assembly, the rear infrared lens assembly, the infrared zoom lens assembly, and the infrared filter switching assembly are all aligned; the optical axis of the infrared dichroic filter assembly forms a 45° angle with the optical axis of the front infrared lens assembly.

[0006] In the aforementioned variable-focus infrared lens suitable for a wide temperature field, the infrared dichroic filter assembly includes an infrared dichroic filter, an infrared dichroic filter frame, and an infrared dichroic filter retainer; wherein, the infrared dichroic filter is disposed within the infrared dichroic filter frame; the infrared dichroic filter retainer is disposed on the infrared dichroic filter frame, and the infrared dichroic filter retainer serves to axially limit the infrared dichroic filter.

[0007] In the aforementioned variable-focus infrared lens suitable for a wide temperature field, the front infrared lens assembly includes a first infrared lens, a second infrared lens, a third infrared lens, a first infrared lens frame, a second infrared lens frame, a third infrared lens frame, a first spacer, a second spacer, a third spacer, a front infrared lens barrel baffle, and a front infrared lens barrel; wherein, the first infrared lens is disposed within the first infrared lens frame, the second infrared lens is disposed within the second infrared lens frame, and the third infrared lens is disposed within the third infrared lens frame; the first infrared lens frame is disposed within the front infrared lens barrel via the first spacer, the second infrared lens frame is disposed within the front infrared lens barrel via the second spacer, and the third infrared lens frame is disposed within the front infrared lens barrel via the third spacer; the first infrared lens frame is located at the front of the second infrared lens frame, and the third infrared lens frame is located at the rear of the second infrared lens frame; the optical axes of the first infrared lens, the second infrared lens, and the third infrared lens are all aligned; the front infrared lens barrel baffle is disposed at the front end frame of the front infrared lens barrel.

[0008] In the aforementioned variable-focus infrared lens suitable for a wide temperature field, the rear infrared lens assembly includes a sixth infrared lens, a sixth infrared lens frame, a sixth spacer, a rear infrared lens barrel baffle, and a rear infrared lens barrel; wherein, the sixth infrared lens is disposed within the sixth infrared lens frame; the sixth infrared lens frame is disposed within the rear infrared lens barrel via the sixth spacer; and the rear infrared lens barrel baffle is disposed at the front end frame of the rear infrared lens barrel.

[0009] In the aforementioned variable-focus infrared lens applicable to a wide temperature field, the infrared zoom lens assembly includes a zoom lens group, an equivalent lens barrel, two zoom adjustment shims, and an infrared zoom mechanism; wherein, the zoom lens group is connected to one arm of the infrared zoom mechanism via one zoom adjustment shim; and the equivalent lens barrel is connected to another arm of the infrared zoom mechanism via another zoom adjustment shim.

[0010] In the aforementioned variable-focus infrared lens suitable for a wide temperature field, the zoom lens group includes a fourth infrared lens, a fifth infrared lens, a fourth infrared lens frame, a fifth infrared lens frame, a zoom lens barrel, a fourth spacer, a fifth spacer, and an infrared zoom lens barrel baffle. The fourth infrared lens is disposed within the fourth infrared lens frame; the fifth infrared lens is disposed within the fifth infrared lens frame; the fourth infrared lens frame is disposed inside the zoom lens barrel via the fourth spacer; the fifth infrared lens frame is disposed inside the zoom lens barrel via the fifth spacer; the optical axis of the fourth infrared lens is aligned with the optical axis of the fifth infrared lens; the fifth infrared lens is located behind the light rays of the fourth infrared lens; and the infrared zoom lens barrel baffle is disposed within the front end frame of the zoom lens barrel.

[0011] In the aforementioned variable-focus infrared lens applicable to a wide temperature field, the infrared filter switching assembly includes a first infrared filter, a second infrared filter, a first infrared filter frame, a second infrared filter frame, and an infrared filter switching mechanism; wherein, the first infrared filter is disposed within the first infrared filter frame; the second infrared filter is disposed within the second infrared filter frame; the first infrared filter frame is connected to one swing arm of the infrared filter switching mechanism; and the second infrared filter frame is connected to the other swing arm of the infrared filter switching mechanism.

[0012] In the aforementioned variable-focus infrared lens applicable to a wide temperature field, both the first and second surfaces of the infrared dichroic filter are planar. The first surface of the infrared dichroic filter is a reflective surface, capable of reflecting light except for the 1500–1700 nm spectral band, with a reflectivity ≥99%. The second surface of the infrared dichroic filter is a transmissive surface, capable of transmitting light in the 1500–1700 nm spectral band, with a transmittance ≥98%.

[0013] In the aforementioned variable-focus infrared lens suitable for a wide temperature field, the first infrared lens is made of H-ZK5 material, and its first and second surfaces are convex; the second infrared lens is made of N-SF2 material, and its first and second surfaces are concave; the third infrared lens is made of H-LAF3B material, and its first and second surfaces are convex.

[0014] In the aforementioned variable-focus infrared lens suitable for a wide temperature field, the material of the sixth infrared lens is N-KZFS2, the first surface of the sixth infrared lens is concave, and the second surface of the sixth infrared lens is concave; the material of the fourth infrared lens is H-K51, the first surface of the fourth infrared lens is concave, and the second surface of the fourth infrared lens is concave; the material of the fifth infrared lens is ZF52, the first surface of the fifth infrared lens is convex, and the second surface of the fifth infrared lens is convex.

[0015] Compared with the prior art, the present invention has the following advantages:

[0016] (1) The variable focus infrared lens in this invention can capture the infrared characteristics of the target object for the laser emitting device in harsh environments of -28℃ to +60℃ by thermal matching between different optical element materials. Compared with conventional infrared lenses, it has a higher environmental adaptability.

[0017] (2) The infrared lens in this invention is provided with a switching mechanism at the end, which can switch different types of infrared filters into the imaging optical path according to different observation tasks to meet different working requirements.

[0018] (3) The lens in this invention is mounted horizontally, with only one mounting base connected and fixed to the platform. The infrared zoom mechanism and the infrared filter switching mechanism are both within the optical path, which makes the lens structure more compact.

[0019] (4) The lens in this invention adopts a modular design, with different components individually fixed on the infrared lens base. It is easy to disassemble, convenient for maintenance and replacement, has strong practicality, and facilitates subsequent optimization and upgrading of the lens. Attached Figure Description

[0020] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0021] Figure 1 This is a schematic diagram of the structure of a variable-focus infrared lens lens suitable for a wide temperature field provided in an embodiment of the present invention;

[0022] Figure 2 This is a schematic diagram of the structure of the infrared lens mount provided in an embodiment of the present invention;

[0023] Figure 3 This is a schematic diagram of the structure of the infrared color separation film assembly provided in an embodiment of the present invention;

[0024] Figure 4 This is a schematic diagram of the structure of the front infrared lens assembly provided in an embodiment of the present invention;

[0025] Figure 5 This is a schematic diagram of the structure of the rear infrared lens assembly provided in an embodiment of the present invention;

[0026] Figure 6 This is a schematic diagram of the structure of the infrared zoom lens assembly provided in an embodiment of the present invention;

[0027] Figure 7 This is a schematic diagram of the zoom lens group provided in an embodiment of the present invention;

[0028] Figure 8 This is a schematic diagram of the structure of the infrared filter switching assembly provided in an embodiment of the present invention. Detailed Implementation

[0029] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the disclosure to those skilled in the art. It should be noted that, unless otherwise specified, the embodiments and features described herein can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0030] Figure 1 This is a schematic diagram of the structure of a variable-focus infrared lens suitable for a wide temperature field, provided in an embodiment of the present invention. Figure 1 As shown, the variable-focus infrared lens suitable for a wide temperature field includes: an infrared lens base 1, an infrared dichroic filter assembly 2, a front infrared lens assembly 3, a rear infrared lens assembly 4, an infrared zoom lens assembly 5, and an infrared filter switching assembly 6; wherein, the infrared dichroic filter assembly 2, the front infrared lens assembly 3, the rear infrared lens assembly 4, the infrared zoom lens assembly 5, and the infrared filter switching assembly 6 are all fixed on the upper surface of the infrared lens base 1; the optical axes of the front infrared lens assembly 3, the rear infrared lens assembly 4, the infrared zoom lens assembly 5, and the infrared filter switching assembly 6 are all aligned; the optical axis of the infrared dichroic filter assembly 2 forms a 45° angle with the optical axis of the front infrared lens assembly 3.

[0031] The infrared dichroic filter assembly 2 allows light in the spectral range of 1500–1700 nm to pass through, while reflecting light in other spectral ranges vertically upwards to provide incident light for other optical systems. The metal support structure is made of aluminum alloy with a black anodized outer surface to accommodate optical components made of different materials.

[0032] The upper surface of the infrared lens mount provides mounting interfaces for the infrared dichroic filter assembly, front infrared lens assembly, rear infrared lens assembly, infrared zoom lens assembly, and infrared filter switching assembly. The lower surface of the infrared lens mount has a flange that connects to the platform. The infrared lens mount adopts a lightweight design and incorporates structural avoidance along the movement path of the moving mechanism to prevent collisions and damage to other structures during movement.

[0033] During assembly and adjustment, first install the front infrared lens assembly at the corresponding position on the upper surface of the infrared lens mount. Using the optical axis of the front infrared lens assembly as a reference, install the rear infrared lens assembly, infrared zoom lens assembly, and infrared filter switching assembly in sequence, aligning the optical axes of the rear infrared lens assembly, infrared zoom lens assembly, and infrared filter switching assembly with the optical axis of the front infrared lens assembly. The optical axis of the infrared dichroic filter assembly forms a 45° angle with the optical axes of the other components.

[0034] like Figure 2 As shown, the infrared lens mount 1 is made of aluminum alloy and can provide an installation interface for other components.

[0035] like Figure 3 As shown, the infrared color separation component 2 includes an infrared color separation 7, an infrared color separation frame 8, and an infrared color separation baffle 9; wherein, the infrared color separation 7 is disposed within the infrared color separation frame 8; the infrared color separation baffle 9 is disposed on the infrared color separation frame 8, and the infrared color separation baffle 9 plays an axial limiting role for the infrared color separation.

[0036] The infrared dichroic filter assembly 2 includes one infrared dichroic filter 7, one infrared dichroic filter frame 8, and three infrared dichroic filter retainers 9. The infrared dichroic filter material is Silica. The first and second surfaces of the infrared dichroic filter 7 are both planar, with a center thickness of 6 mm. The first surface of the infrared dichroic filter 7 is a reflective surface, reflecting light except in the 1500–1700 nm spectral band, with a reflectivity ≥99%. The second surface of the infrared dichroic filter 7 is a transmissive surface, transmitting light in the 1500–1700 nm spectral band, with a transmittance ≥98%.

[0037] There is a 3mm gap between the outer diameter of the infrared color separator and the inner diameter of the infrared color separator frame 8. Silicone rubber is injected into this gap to fix the infrared color separator 7 in the corresponding position inside the infrared color separator frame 8. Finally, three infrared color separator retainers 9 are installed on the end face of the infrared color separator frame using standard fasteners to provide axial positioning for the infrared color separator.

[0038] like Figure 4As shown, the front infrared lens assembly 3 includes a first infrared lens 10, a second infrared lens 11, a third infrared lens 12, a first infrared lens frame 13, a second infrared lens frame 14, a third infrared lens frame 15, a first spacer 16, a second spacer 17, a third spacer 18, a front infrared lens barrel baffle 19, and a front infrared lens barrel 20; wherein, the first infrared lens 10 is disposed within the first infrared lens frame 13, the second infrared lens 11 is disposed within the second infrared lens frame 14, and the third infrared lens 12 is disposed within the third infrared lens frame 15; the first infrared lens frame 13 is connected to the first infrared lens barrel 20 by the first infrared lens 11, the second infrared lens 12, the third infrared lens 13, the second infrared lens 14, the third infrared lens 15, the first infrared lens frame 16, the second infrared lens 17, the third infrared lens 18, the first infrared lens barrel 19, the second infrared lens barrel 20, the third infrared lens barrel 20, the second infrared lens 11, the third infrared lens 12, the third infrared lens 13 ... third infrared lens 14, the third infrared lens 15, the third infrared lens 16, the second infrared lens 17, the third infrared lens 18, the third infrared lens barrel 20, the third infrared lens barrel 20, the third infrared lens 11, the second infrared lens 12, the third infrared lens 13, the second infrared lens 11, the third infrared lens 12, the third infrared lens 13, the third infrared lens 1 A spacer 16 is disposed inside the front infrared lens tube 20, a second infrared lens frame 14 is disposed inside the front infrared lens tube 20 via a second spacer 17, and a third infrared lens frame 15 is disposed inside the front infrared lens tube 20 via a third spacer 18; the first infrared lens frame 13 is located in front of the second infrared lens frame 14, and the third infrared lens frame 15 is located in rear of the second infrared lens frame 14; the optical axes of the first infrared lens 10, the second infrared lens 11, and the third infrared lens 12 are all aligned; a front infrared lens tube baffle 19 is disposed at the front end frame of the front infrared lens tube 20.

[0039] The front infrared lens assembly 3 includes a first infrared lens 10, a second infrared lens 11, a third infrared lens 12, a first infrared lens frame 13, a second infrared lens frame 14, a third infrared lens frame 15, a first spacer 16, a second spacer 17, a third spacer 18, a front infrared lens barrel baffle 19, and a front infrared lens barrel 20.

[0040] First, install the first infrared lens 10, the second infrared lens 11, and the third infrared lens 12 into their respective positions within the first infrared lens frame 13, the second infrared lens frame 14, and the third infrared lens frame 15, respectively, and secure them with adhesive. Then, install them sequentially into the front infrared lens barrel 20, securing them with adhesive. During installation, use the first spacer 16, the second spacer 17, and the third spacer 18 to adjust the inter-lens distance and align the optical axes of the first infrared lens 10, the second infrared lens 11, and the third infrared lens 12. Finally, use the front infrared lens barrel baffle 19 at the very front to press down all the components inside the front infrared lens barrel 20.

[0041] The materials of the first, second, and third infrared lenses are H-ZK5, N-SF2, and H-LAF3B, respectively. The first infrared lens has a convex first surface and a concave second surface, with a center thickness of 10.117 mm. The second infrared lens has a concave first surface and a convex second surface, with a center thickness of 6.38 mm. The third infrared lens has a convex first surface and a concave second surface, with a center thickness of 10.263 mm.

[0042] The first, second, and third infrared lenses correspond to the first, second, and third infrared lens frames, respectively, ensuring a 3mm gap between the outer diameter of each infrared lens and the inner diameter of its corresponding infrared lens frame. Silicone rubber is injected into these gaps, and the first, second, and third infrared lenses are then fixed at their respective positions within the first, second, and third infrared lens frames.

[0043] Next, the first infrared lens frame, the second infrared lens frame, and the third infrared lens frame, which contain optical elements, are sequentially installed into the corresponding positions inside the front infrared lens tube. During the installation process, the first spacer, the second spacer, and the third spacer are used to adjust the inter-lens distance and align the optical axes of the first infrared lens, the second infrared lens, and the third infrared lens.

[0044] There is a 3mm gap between the inner diameter of the front infrared lens barrel and the outer diameters of the first, second, and third infrared lens frames. Silicone rubber is injected into each gap, and the first, second, and third infrared lens frames are then fixed at their respective positions inside the front infrared lens barrel. Finally, a front infrared lens barrel baffle is used at the very front of the front infrared lens barrel to press the internal components together, thus providing axial restraint.

[0045] like Figure 5 As shown, the rear infrared lens assembly 4 includes a sixth infrared lens 21, a sixth infrared lens frame 22, a sixth spacer 23, a rear infrared lens barrel baffle 24, and a rear infrared lens barrel 25; wherein, the sixth infrared lens 21 is disposed within the sixth infrared lens frame 22; the sixth infrared lens frame 22 is disposed within the rear infrared lens barrel 25 via the sixth spacer 23; and the rear infrared lens barrel baffle 24 is disposed at the front end frame of the rear infrared lens barrel 25.

[0046] First, install the sixth infrared lens 21 into its corresponding position within the sixth infrared lens frame 22 and secure it with adhesive. Then, install it into the rear infrared lens tube 25 and secure it with adhesive, adjusting the lens spacing using the sixth spacer 23 during installation. Finally, use the rear infrared lens tube baffle 24 at the front end to press down all components inside the rear infrared lens tube 25.

[0047] The sixth infrared lens is made of N-KZFS2 material. The first surface of the sixth infrared lens is concave, the second surface is convex, and the center thickness is 11.964 mm. First, install the sixth infrared lens into the corresponding position within the sixth infrared lens frame, ensuring a 3 mm gap between the outer diameter of the sixth infrared lens and the inner diameter of the sixth infrared lens frame. Inject silicone rubber into this gap to fix the sixth infrared lens in its correct position within the sixth infrared lens frame.

[0048] Next, the sixth infrared lens frame, containing the optical elements, is installed into the corresponding position inside the rear infrared lens tube. During installation, the sixth spacer is used to adjust the lens spacing. There is a 3mm gap between the inner diameter of the rear infrared lens tube and the outer diameter of the sixth infrared lens frame. Silicone rubber is injected into this gap to fix the sixth infrared lens frame in its corresponding position inside the rear infrared lens tube. Finally, a rear infrared lens tube baffle is used at the very front of the rear infrared lens tube to press the internal components together, providing axial positioning.

[0049] like Figure 6 As shown, the infrared zoom lens assembly 5 includes a zoom lens group 26, an equivalent lens barrel 27, two zoom adjustment shims 28, and an infrared zoom mechanism 29; wherein, the zoom lens group 26 is connected to one arm of the infrared zoom mechanism 29 through one zoom adjustment shim 28; the equivalent lens barrel 27 is connected to the other arm of the infrared zoom mechanism 29 through the other zoom adjustment shim 28.

[0050] Use the zoom adjustment shim 28 to adjust the relative positions within the zoom lens group 26 and the infrared equivalent lens barrel 27. When switching gears, the optical axis of the zoom lens group 26 and the axis of the equivalent lens barrel 27 can be aligned with the optical axis of the front infrared lens assembly 3, respectively.

[0051] The infrared zoom mechanism 29 is equipped with two swing arms, which are connected to the zoom lens group 26 and the infrared equivalent lens barrel 27 respectively using standard fasteners. The positional relationship between the zoom lens group 26 and the infrared equivalent lens barrel 27 is adjusted by two zoom adjustment shims 28.

[0052] The two swing arms of the infrared zoom mechanism can swing clockwise or counterclockwise with high precision around their centers, allowing the zoom lens group to quickly enter and exit the optical path to switch between telephoto and focal length lenses in 3 seconds. When the zoom lens group enters the optical path, its optical axis is aligned with the optical axis of the front infrared lens assembly, with an alignment accuracy within 15 seconds. When the infrared equivalent lens barrel enters the optical path, its axis is aligned with the optical axis of the front infrared lens assembly.

[0053] The infrared equivalent lens tube contains no optical elements; its function is solely to eliminate stray light. The swing arm driving the infrared zoom mechanism functions as an infrared short-focus lens when the zoom lens group enters the optical path and the infrared equivalent lens tube exits the optical path. When the zoom lens group exits the optical path and the infrared equivalent lens tube enters the optical path, it functions as an infrared long-focus lens.

[0054] like Figure 7As shown, the zoom lens group 26 includes a fourth infrared lens 30, a fifth infrared lens 31, a fourth infrared lens frame 32, a fifth infrared lens frame 33, a zoom lens barrel 34, a fourth spacer 35, a fifth spacer 36, and an infrared zoom lens barrel baffle 37. The fourth infrared lens 30 is disposed within the fourth infrared lens frame 32; the fifth infrared lens 31 is disposed within the fifth infrared lens frame 33; the fourth infrared lens frame 32 is disposed inside the zoom lens barrel 34 via the fourth spacer 35; the fifth infrared lens frame 33 is disposed inside the zoom lens barrel 34 via the fifth spacer 36; the optical axis of the fourth infrared lens 30 is aligned with the optical axis of the fifth infrared lens 31; the fifth infrared lens 31 is located behind the light rays of the fourth infrared lens 30; and the infrared zoom lens barrel baffle 37 is disposed within the front frame of the zoom lens barrel 34.

[0055] First, install the fourth infrared lens 30 and the fifth infrared lens 31 into their respective positions within the fourth infrared lens frame 32 and the fifth infrared lens frame 33, respectively, and secure them using adhesive. Then, install them sequentially into the zoom lens barrel 34, securing them with adhesive. During installation, use the fourth spacer 35 and the fifth spacer 36 to adjust the inter-lens distance and align the optical axes of the fourth infrared lens 30 and the fifth infrared lens 31. Finally, use the infrared zoom lens barrel baffle 37 at the very front to press down all the internal components of the zoom lens barrel 34.

[0056] The fourth and fifth infrared lenses are made of H-K51 and ZF52 materials, respectively. The first surface of the fourth infrared lens is concave, the second surface is convex, and the center thickness is 10.238 mm. The first surface of the fifth infrared lens is convex, the second surface is concave, and the center thickness is 12.838 mm.

[0057] First, install the fourth and fifth infrared lenses into their respective positions within the fourth and fifth infrared lens frames, ensuring a 3mm gap between the outer diameter of each infrared lens and the inner diameter of the corresponding infrared lens frame. Then, inject silicone rubber into the gaps and fix the fourth and fifth infrared lenses in their respective positions within the fourth and fifth infrared lens frames.

[0058] Next, the fourth and fifth infrared lens frames, which contain optical elements, are sequentially installed into the corresponding positions inside the zoom lens barrel. During the installation process, the fourth and fifth spacers are used to adjust the inter-lens distance and align the optical axes of the fourth and fifth infrared lenses.

[0059] There is a 3mm gap between the inner diameter of the zoom lens barrel and the outer diameters of the fourth and fifth infrared lens frames. Silicone rubber is injected into the gaps to fix the fourth and fifth infrared lens frames at their respective positions inside the zoom lens barrel. Finally, an infrared zoom lens barrel baffle is used at the very front of the zoom lens barrel to press the internal components together, serving as an axial limit.

[0060] like Figure 8 As shown, the infrared filter switching assembly 6 includes a first infrared filter 38, a second infrared filter 39, a first infrared filter frame 40, a second infrared filter frame 41, and an infrared filter switching mechanism 42; wherein, the first infrared filter 38 is disposed within the first infrared filter frame 40; the second infrared filter 39 is disposed within the second infrared filter frame 41; the first infrared filter frame 40 is connected to one swing arm of the infrared filter switching mechanism 42; and the second infrared filter frame 41 is connected to the other swing arm of the infrared filter switching mechanism 42.

[0061] First, the first infrared filter 38 and the second infrared filter 39 are respectively installed into their corresponding positions within the first infrared filter frame 40 and the second infrared filter frame 41, and fixed using adhesive. Then, the first infrared filter frame 40 and the second infrared filter frame 41 are sequentially installed into the corresponding swing arms of the infrared filter switching mechanism 42. During installation, the relative positions of the first infrared filter frame 40 and the second infrared filter frame are adjusted using the infrared filter frame adjusting shims 43. When switching gears, the optical axis of the infrared filter engaging the optical path is aligned with the optical axis of the front infrared lens assembly 3.

[0062] The first and second infrared filters are made of Silica. Both the first and second surfaces of the first and second infrared filters are flat, with a center thickness of 3 mm. The first infrared filter has a transmittance of 95% only for light in the 1600±5nm spectral band, and the second infrared filter has a transmittance of 95% only for light in the 1550-1650nm spectral band, thus achieving a filtering effect.

[0063] First, install the first infrared filter and the second infrared filter into their respective positions within the first infrared filter frame and the second infrared filter frame, ensuring a 3mm gap between the outer diameter of each infrared filter and the inner diameter of the corresponding infrared filter frame. Inject silicone rubber into the gaps to fix the first infrared filter and the second infrared filter into their respective positions within the first infrared filter frame and the second infrared filter frame.

[0064] The infrared filter switching mechanism has two swing arms, which are connected to two first infrared filter frames and second infrared filter frames equipped with optical elements using standard fasteners. The relative positions of the first infrared filter frames and the second infrared filter frames can be adjusted by adjusting the infrared filter frame shims.

[0065] The two swing arms of the infrared filter switching mechanism can swing clockwise or counterclockwise with high precision around the center of the swing arms, thereby driving the switching of the first and second infrared filters in the optical path to achieve different working requirements. When switching gears, the optical axis of the infrared filter entering the optical path can be aligned with the optical axis of the front infrared lens assembly.

[0066] The lens is mounted horizontally, with only one mounting base flange connecting it to the platform. The infrared zoom mechanism and infrared filter switching mechanism are both located within the optical path, making the lens structure more compact and facilitating lens assembly, adjustment, testing, installation, and maintenance.

[0067] The air gap between the infrared dichroic filter and the first infrared lens is 50 mm, the air gap between the first infrared lens and the second infrared lens is 5.082 mm, the air gap between the second infrared lens and the third infrared lens is 15.617 mm, the air gap between the third infrared lens and the fourth infrared lens is 10.807 mm, the air gap between the fourth infrared lens and the fifth infrared lens is 48.351 mm, the air gap between the fifth infrared lens and the sixth infrared lens is 10.693 mm, the air gap between the sixth infrared lens and the infrared filter is 13.102 mm, and the air gap between the infrared filter and the imaging focal plane is 18.728 mm.

[0068] Each optical element is supported by a corresponding aluminum alloy frame. Aluminum alloy has high thermal conductivity, so even in harsh temperature environments, it will not produce a temperature gradient on the optical element. In addition, there is a certain gap between the optical element and the frame. The silicone rubber injected into the gap can effectively offset the effect of thermal stress on the optical element.

[0069] This infrared lens has an outer envelope of 260mm × 320mm × 255mm, a first-order frequency of 80Hz, and weighs only 7kg. Suitable for use in laser optical systems, it can operate normally in a wide temperature range of -28℃ to +65℃ without additional temperature control measures. It can still capture the infrared characteristics of target objects for laser emitting devices and can quickly and accurately switch between long and short focal lengths, allowing for target tracking at different locations. A switching mechanism is located at the end of the lens, allowing for the selection of different filters to meet various application requirements.

[0070] Specifically, the variable-focus infrared lens of this embodiment, applicable to a wide temperature field, can capture the infrared characteristics of a target object for a laser emitting device. Passive thermal compensation is achieved through thermal matching between materials. It can be used normally in harsh environments ranging from -28℃ to +60℃ and has high environmental adaptability. It includes an infrared lens base 1, an infrared dichroic filter assembly 2, a front infrared lens assembly 3, a rear infrared lens assembly 4, an infrared zoom lens assembly 5, an infrared filter switching assembly 6, and several adjustment shims.

[0071] The infrared dichroic filter assembly 2, the front infrared lens assembly 3, the rear infrared lens assembly 4, the infrared zoom lens assembly 5, and the infrared filter switching assembly 6 are all fixed to the upper surface of the infrared lens base 1 using standard fasteners. The optical axis of the infrared dichroic filter assembly 2 is at a 45° angle to the optical axes of the other components. Adjustment shims are provided between each component and the infrared lens base 1 to align the optical axes of each component.

[0072] The upper surface of the infrared lens base 1 provides mounting interfaces for the infrared dichroic filter assembly 2, the front infrared lens assembly 3, the rear infrared lens assembly 4, the infrared zoom lens assembly 5, and the infrared filter switching assembly 6. The lower surface flange of the infrared lens base 1 is stably connected to the platform. The infrared lens base 1 adopts a lightweight design and avoids collisions with other structures along the movement path of the moving mechanism.

[0073] During assembly and adjustment, first install the front infrared lens assembly 3 at the corresponding position on the upper surface of the infrared lens base 1. Using the optical axis of the front infrared lens assembly 3 as a reference, install the rear infrared lens assembly 4, the infrared zoom lens assembly 5, and the infrared filter switching assembly 6 in sequence, aligning the optical axes of the rear infrared lens assembly 4, the infrared zoom lens assembly 5, and the infrared filter switching assembly 6 with the optical axis of the front infrared lens assembly 3. The optical axis of the infrared dichroic filter assembly 2 forms a 45° angle with the optical axes of the other components.

[0074] The infrared lens has an entrance pupil diameter of 25.9 mm, a working spectral range of 1500–1700 nm, a short focal length field of view of ±2.69° × ±2.16°, a long focal length field of view of ±1.42° × ±1.14°, a short focal length focal length of 104.53 mm, and a long focal length focal length of 195.95 mm.

[0075] This infrared lens comprises one infrared dichroic filter, six infrared lenses, and two infrared filters. The parameters of each optical element are shown in Table 1. The remaining metal support structure is made of 5A06 aluminum alloy and is used to accommodate optical elements made of different materials. The outer surface of the metal support structure is anodized in black. The outer diameter of the metal frame that assembles with each optical element is 10mm larger than the aperture of the corresponding optical element.

[0076] The air gap between the infrared dichroic filter 7 and the first infrared lens 10 is 50 mm; the air gap between the first infrared lens 10 and the second infrared lens 11 is 5.082 mm; the air gap between the second infrared lens 11 and the third infrared lens 12 is 15.617 mm; the air gap between the third infrared lens 12 and the fourth infrared lens 30 is 10.807 mm; the air gap between the fourth infrared lens 30 and the fifth infrared lens 31 is 48.351 mm; the air gap between the fifth infrared lens 31 and the sixth infrared lens 21 is 10.693 mm; the air gap between the sixth infrared lens and the first infrared filter 38 or the second infrared filter 39 is 13.102 mm; and the air gap between the first infrared filter 38 or the second infrared filter 39 and the imaging focal plane is 18.728 mm.

[0077] Table 1 Optical Component Parameters

[0078]

[0079] The infrared dichroic filter assembly 2 in the infrared lens includes one infrared dichroic filter 7, one infrared dichroic filter frame 8, and three infrared dichroic filter blocks 9.

[0080] The infrared dichroic filter 7 is made of Silica. Both its first and second surfaces are flat, with a center thickness of 6 mm. The first surface is a reflective surface, reflecting light except in the 1500–1700 nm spectral band, with a reflectivity ≥99%. The second surface is a transmissive surface, transmitting light in the 1500–1700 nm spectral band, with a transmittance ≥98%.

[0081] The infrared color separation frame 8 has four injection holes around its perimeter. First, insert the infrared color separation sheet 7 into the corresponding position within the infrared color separation frame 8, ensuring a 3mm gap between the outer diameter of the infrared color separation sheet 7 and the inner diameter of the infrared color separation frame 8. Inject RTV566 silicone rubber into this gap through the four injection holes to fix the infrared color separation sheet 7 in its corresponding position within the infrared color separation frame 8. Finally, install three infrared color separation sheet retainers 9 at the end face of the infrared color separation frame 8 using standard fasteners to provide axial positioning for the infrared color separation sheet 7.

[0082] The front infrared lens assembly 3 of the infrared lens includes a first infrared lens 10, a second infrared lens 11, a third infrared lens 12, a first infrared lens frame 13, a second infrared lens frame 14, a third infrared lens frame 15, a first spacer 16, a second spacer 17, a third spacer 18, a front infrared lens barrel baffle 19, and a front infrared lens barrel 20.

[0083] The materials of the first infrared lens 10, the second infrared lens 11, and the third infrared lens 12 are H-ZK5, N-SF2, and H-LAF3B, respectively. The first infrared lens 10 has a convex first surface, a convex second surface, and a center thickness of 10.117 mm. The second infrared lens 11 has a concave first surface, a convex second surface, and a center thickness of 6.38 mm. The third infrared lens 12 has a convex first surface, a convex second surface, and a center thickness of 10.263 mm.

[0084] Four injection holes are provided around the periphery of the first infrared lens frame 13, the second infrared lens frame 14, and the third infrared lens frame 15. First, the first infrared lens 10, the second infrared lens 11, and the third infrared lens 12 are respectively installed into the corresponding positions in the first infrared lens frame 13, the second infrared lens frame 14, and the third infrared lens frame 15, ensuring that there is a 3mm gap between the outer diameter of each infrared lens and the inner diameter of the corresponding infrared lens frame. RTV566 silicone rubber is injected into this gap through the four injection holes to fix the first infrared lens 10, the second infrared lens 11, and the third infrared lens 12 into their corresponding positions in the first infrared lens frame 13, the second infrared lens frame 14, and the third infrared lens frame 15.

[0085] Then, the first infrared lens frame 13, the second infrared lens frame 14, and the third infrared lens frame 15, which contain optical elements, are sequentially installed into the corresponding positions inside the front infrared lens tube 20. During the installation process, the first spacer 16, the second spacer 17, and the third spacer 18 are used to adjust the inter-lens distance, and the optical axes of the first infrared lens 10, the second infrared lens 11, and the third infrared lens 12 are aligned.

[0086] There is a 3mm gap between the inner diameter of the front infrared lens barrel 20 and the outer diameters of the first infrared lens frame 13, the second infrared lens frame 14, and the third infrared lens frame 15. Four injection holes are provided at the corresponding positions of the front infrared lens barrel 20 and the first, second, and third infrared lens frames 13 and 14, respectively. RTV566 silicone rubber is injected into these gaps through the four injection holes to fix the first, second, and third infrared lens frames 14 and 15 in their respective positions within the front infrared lens barrel 20. Finally, a front infrared lens barrel baffle 19 is used at the very front end of the front infrared lens barrel 20 to press the internal components together, thus providing axial positioning.

[0087] The rear infrared lens assembly 4 of the infrared lens includes a sixth infrared lens 21, a sixth infrared lens frame 22, a rear infrared lens tube 25, a sixth spacer 23, and a rear infrared lens tube baffle 24.

[0088] The material of the sixth infrared lens 21 is N-KZFS2. The first surface of the sixth infrared lens 21 is concave, the second surface is concave, and the center thickness is 11.964 mm.

[0089] The sixth infrared lens frame 22 has four injection holes around its perimeter. First, the sixth infrared lens 21 is installed in the corresponding position inside the sixth infrared lens frame 22, ensuring a 3mm gap between the outer diameter of the sixth infrared lens 21 and the inner diameter of the sixth infrared lens frame 22. RTV566 silicone rubber is then injected into this gap through the four injection holes to fix the sixth infrared lens 21 in the corresponding position inside the sixth infrared lens frame 22.

[0090] Next, the sixth infrared lens frame 22 containing the optical elements is installed into the corresponding position of the rear infrared lens tube 25, and the lens spacing is adjusted using the sixth spacer 23 during the installation process.

[0091] There is a 3mm gap between the inner diameter of the rear infrared lens tube 25 and the outer diameter of the sixth infrared lens frame 22. Four injection holes are provided at the corresponding positions of the rear infrared lens tube 25 and the sixth infrared lens frame 22. RTV566 silicone rubber is injected into this gap through the four injection holes to fix the sixth infrared lens frame 22 in its corresponding position inside the rear infrared lens tube 25. Finally, a rear infrared lens tube baffle 24 is used at the very front end of the rear infrared lens tube 25 to press the internal components together, serving as an axial limit.

[0092] The infrared zoom lens assembly 5 in the infrared lens includes a zoom lens group 26, an infrared equivalent lens barrel 27, two zoom adjustment shims 29, and an infrared zoom mechanism 29.

[0093] The infrared zoom mechanism 29 is equipped with two swing arms, which are connected to the zoom lens group 26 and the infrared equivalent lens barrel 27 respectively using standard fasteners. The positional relationship between the zoom lens group 26 and the infrared equivalent lens barrel 27 is adjusted by two zoom adjustment shims 29.

[0094] The two arms of the infrared zoom mechanism 29 can swing clockwise or counterclockwise with high precision around their centers, thereby quickly entering and exiting the zoom lens group 26 in the optical path to achieve the switching function between telephoto and short focal lengths, with a switching time of 3 seconds. When the zoom lens group 26 enters the optical path, its optical axis is aligned with the optical axis of the front infrared lens assembly 3, with an alignment accuracy within 15 seconds. When the infrared equivalent lens barrel 27 enters the optical path, its axis is aligned with the optical axis of the front infrared lens assembly 3.

[0095] The infrared equivalent lens tube 27 contains no optical elements and only serves to eliminate stray light. The swing arm driving the infrared zoom mechanism 29 functions as an infrared short-focus lens when the zoom lens group 26 is in the optical path and the infrared equivalent lens tube 27 is out of the optical path. When the zoom lens group 26 is in the optical path and the infrared equivalent lens tube 27 is in the optical path, it functions as an infrared long-focus lens.

[0096] The zoom lens group 26 in the infrared lens includes a fourth infrared lens 30, a fifth infrared lens 31, a fourth infrared lens frame 32, a fifth infrared lens frame 33, a zoom lens barrel 34, a fourth spacer 35, a fifth spacer 36, and an infrared zoom lens barrel baffle 37.

[0097] The fourth infrared lens 30 and the fifth infrared lens 31 are made of H-K51 and ZF52 materials, respectively. The first surface of the fourth infrared lens 30 is concave, the second surface is concave, and the center thickness is 10.238 mm. The first surface of the fifth infrared lens 31 is convex, the second surface is convex, and the center thickness is 12.838 mm.

[0098] The fourth infrared lens frame 32 and the fifth infrared lens frame 33 are respectively provided with four injection holes. First, the fourth infrared lens 30 and the fifth infrared lens 31 are installed in the corresponding positions in the fourth infrared lens frame 32 and the fifth infrared lens frame 33, respectively, and a 3mm gap is ensured between the outer diameter of each infrared lens and the inner diameter of the corresponding infrared lens frame. RTV566 silicone rubber is injected into this gap through the four injection holes, and the fourth infrared lens 30 and the fifth infrared lens 31 are fixed in the corresponding positions in the fourth infrared lens frame 32 and the fifth infrared lens frame 33, respectively.

[0099] Then, the fourth infrared lens frame 32 and the fifth infrared lens frame 33, which contain optical elements, are sequentially installed into the corresponding positions inside the zoom lens barrel 34. During the installation process, the fourth spacer 35 and the fifth spacer 36 are used to adjust the inter-lens distance and align the optical axes of the fourth infrared lens 30 and the fifth infrared lens 31.

[0100] There is a 3mm gap between the inner diameter of the zoom lens barrel 34 and the outer diameters of the fourth infrared lens frame 32 and the fifth infrared lens frame 33. Four injection holes are provided at the corresponding positions of the zoom lens barrel 34 and the fourth and fifth infrared lens frames 32 and 33, respectively. RTV566 silicone rubber is injected into these gaps through the four injection holes to fix the fourth and fifth infrared lens frames 32 and 33 in their corresponding positions within the zoom lens barrel 34. Finally, an infrared zoom lens barrel baffle 37 is used at the very front end of the zoom lens barrel 34 to press the internal components together, providing axial positioning.

[0101] The infrared filter switching assembly 6 in the infrared lens includes a first infrared filter 38 and a second infrared filter 39, a first infrared filter frame 40, a second infrared filter frame 41, an infrared filter switching mechanism 42, and two infrared filter frame adjustment shims 43.

[0102] The first infrared filter 38 and the second infrared filter 39 are made of Silica. Both the first and second surfaces of the first infrared filter 38 and the second infrared filter 39 are planar, with a center thickness of 3 mm. The first infrared filter 38 has a transmittance of 95% only for light in the 1600±5nm spectral band, and the second infrared filter 39 has a transmittance of 95% only for light in the 1550-1650nm spectral band, thus achieving a filtering effect.

[0103] The first infrared filter frame 40 and the second infrared filter frame 41 are respectively provided with four injection holes around their perimeters. First, the first infrared filter 38 and the second infrared filter 39 are respectively installed into the corresponding positions in the first infrared filter frame 40 and the second infrared filter frame 41, ensuring that there is a 3mm gap between the outer diameter of each infrared filter and the inner diameter of the corresponding infrared filter frame. RTV566 silicone rubber is injected into this gap through the four injection holes to fix the first infrared filter 38 and the second infrared filter 39 into the corresponding positions in the first infrared filter frame 40 and the second infrared filter frame 41.

[0104] The infrared filter switching mechanism 42 is equipped with two swing arms, which are connected to two first infrared filter frames 40 and second infrared filter frames 41 equipped with optical elements using standard fasteners. The relative positions of the first infrared filter frames 40 and the second infrared filter frames 41 can be adjusted by the infrared filter frame adjusting shims 43.

[0105] The two swing arms of the infrared filter switching mechanism 42 can swing clockwise or counterclockwise with high precision around the center of the swing arms, thereby driving the switching of the first infrared filter 38 and the second infrared filter 39 in the optical path to achieve different working needs. When switching gears, the optical axis of the infrared filter entering the optical path can be aligned with the optical axis of the front infrared lens assembly 3.

[0106] The infrared lens involved in this invention has an outer envelope of 260mm×320mm×255mm, a compact structure, a first-order frequency of 78Hz, and a weight of only 7kg. All components adopt a modular design, and different components are individually fixed on the infrared lens base 1, which makes it easy to install and adjust, easy to disassemble, easy to maintain and replace, and has strong practicality, making it easy to optimize and upgrade in the future.

[0107] This embodiment enables the laser emitting device to capture the infrared characteristics of target objects and can operate normally in harsh environments ranging from -28℃ to +60℃, demonstrating high environmental adaptability. During operation, the lens can switch between telephoto and short focal length within 3 seconds, with a switching accuracy within 15 seconds, allowing it to track targets at different locations. A switching mechanism at the end of the lens allows for the selection of different types of infrared filters to enter the imaging optical path, meeting various operational needs.

[0108] This embodiment addresses the challenge of enabling an infrared lens to capture the infrared characteristics of a target object for a laser emitting device within a wide temperature range of -28℃ to +65℃, while simultaneously allowing for high-precision switching between telephoto and short-focus lenses in a short time. It provides a variable-focus infrared lens suitable for a wide temperature range. This infrared lens has an outer envelope of 260mm × 320mm × 255mm, a first-order frequency of 78Hz, and weighs only 7kg. The modular design of the infrared lens facilitates engineering implementation and improves productivity, effectively enhancing the environmental adaptability and target acquisition capabilities of the laser optical system.

[0109] The variable-focus infrared lens in this embodiment, through thermal matching between different optical element materials, can capture the infrared characteristics of target objects for laser emitting devices in harsh environments ranging from -28℃ to +60℃, exhibiting higher environmental adaptability compared to conventional infrared lenses. The infrared lens in this embodiment can switch between telephoto and short-focus modes within 3 seconds, with a switching accuracy within 15 seconds, and can be used to track target objects at different distances. A switching mechanism is provided at the end of the infrared lens in this embodiment, allowing different types of infrared filters to be switched into the imaging optical path according to different observation tasks, meeting various operational requirements. The lens in this embodiment adopts a horizontal mounting method, with only one mounting base connected and fixed to the platform. Both the infrared zoom mechanism and the infrared filter switching mechanism are within the optical path, resulting in a more compact lens structure. The outer envelope of the infrared lens in this embodiment is 260mm × 320mm × 255mm, with a first-order frequency of 78Hz and a weight of only 7kg. This lens structure is engineering-friendly and improves productivity, effectively enhancing the environmental adaptability and target acquisition capability of the laser optical system. The lens in this embodiment adopts a modular design, with each component individually fixed on the infrared lens base. This makes disassembly easy, facilitating maintenance and replacement, and provides strong practicality, making it convenient for subsequent lens optimization and upgrades.

[0110] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make possible changes and modifications to the technical solutions of the present invention by utilizing the methods and techniques disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solutions of the present invention shall fall within the protection scope of the technical solutions of the present invention.

Claims

1. A variable-focus infrared lens suitable for a wide temperature field, characterized in that... include: The infrared lens mount (1), infrared dichroic filter assembly (2), front infrared lens assembly (3), rear infrared lens assembly (4), infrared zoom lens assembly (5), and infrared filter switching assembly (6); wherein, the number of lenses with optical power is 6; The infrared color separation assembly (2), the front infrared lens assembly (3), the rear infrared lens assembly (4), the infrared zoom lens assembly (5), and the infrared filter switching assembly (6) are all fixed on the upper surface of the infrared lens base (1). The optical axes of the front infrared lens assembly (3), the rear infrared lens assembly (4), the infrared zoom lens assembly (5), and the infrared filter switching assembly (6) are all the same; The infrared zoom lens assembly (5) includes a zoom lens group (26), an equivalent lens barrel (27), two zoom adjustment shims (28), and an infrared zoom mechanism (29); wherein, The zoom lens group (26) is connected to a swing arm of the infrared zoom mechanism (29) via a zoom adjustment shim (28); The equivalent lens barrel (27) is connected to another swing arm of the infrared zoom mechanism (29) via another zoom adjustment shim (28); The zoom lens group (26) includes a fourth infrared lens (30), a fifth infrared lens (31), a fourth infrared lens frame (32), a fifth infrared lens frame (33), a zoom lens barrel (34), a fourth spacer (35), a fifth spacer (36), and an infrared zoom lens barrel baffle (37); wherein, The fourth infrared lens (30) is disposed within the fourth infrared lens frame (32); The fifth infrared lens (31) is disposed within the fifth infrared lens frame (33); The fourth infrared lens frame (32) is disposed inside the zoom lens barrel (34) via the fourth spacer (35); The fifth infrared lens frame (33) is disposed inside the zoom lens barrel (34) via the fifth spacer (36); The optical axis of the fourth infrared lens (30) is consistent with the optical axis of the fifth infrared lens (31); The fifth infrared lens (31) is located behind the light rays of the fourth infrared lens (30); The infrared zoom lens barrel baffle (37) is disposed within the front end frame of the zoom lens barrel (34); The front infrared lens assembly (3) includes a first infrared lens (10), a second infrared lens (11), and a third infrared lens (12). The rear infrared lens assembly (4) includes a sixth infrared lens (21); The material of the first infrared lens (10) is H-ZK5, the first surface of the first infrared lens (10) is convex, and the second surface of the first infrared lens (10) is convex. The material of the second infrared lens (11) is N-SF2, the first surface of the second infrared lens (11) is concave, and the second surface of the second infrared lens (11) is concave. The material of the third infrared lens (12) is H-LAF3B, the first surface of the third infrared lens (12) is convex, and the second surface of the third infrared lens (12) is convex. The material of the sixth infrared lens (21) is N-KZFS2, the first surface of the sixth infrared lens (21) is concave, and the second surface of the sixth infrared lens (21) is concave. The material of the fourth infrared lens (30) is H-K51, the first surface of the fourth infrared lens (30) is concave, and the second surface of the fourth infrared lens (30) is concave. The material of the fifth infrared lens (31) is ZF52. The first surface of the fifth infrared lens (31) is convex, and the second surface of the fifth infrared lens (31) is convex.

2. The variable-focus infrared lens lens suitable for a wide temperature field according to claim 1, characterized in that: The infrared color separation component (2) includes an infrared color separation (7), an infrared color separation frame (8), and an infrared color separation baffle (9); wherein, The infrared color separation film (7) is disposed within the infrared color separation film frame (8); The infrared color separation plate (9) is disposed on the infrared color separation plate frame (8), and the infrared color separation plate (9) plays an axial limiting role for the infrared color separation plate.

3. The variable-focus infrared lens lens suitable for a wide temperature field according to claim 1, characterized in that: The front infrared lens assembly (3) further includes a first infrared lens frame (13), a second infrared lens frame (14), a third infrared lens frame (15), a first spacer (16), a second spacer (17), a third spacer (18), a front infrared lens barrel baffle (19), and a front infrared lens barrel (20); wherein, The first infrared lens (10) is disposed within the first infrared lens frame (13), the second infrared lens (11) is disposed within the second infrared lens frame (14), and the third infrared lens (12) is disposed within the third infrared lens frame (15). The first infrared lens frame (13) is disposed in the front infrared lens tube (20) through the first spacer (16), the second infrared lens frame (14) is disposed in the front infrared lens tube (20) through the second spacer (17), and the third infrared lens frame (15) is disposed in the front infrared lens tube (20) through the third spacer (18). The first infrared lens frame (13) is located in front of the second infrared lens frame (14), and the third infrared lens frame (15) is located behind the second infrared lens frame (14). The optical axes of the first infrared lens (10), the second infrared lens (11), and the third infrared lens (12) are all aligned; The front infrared lens tube baffle (19) is disposed on the front end frame of the front infrared lens tube (20).

4. The variable-focus infrared lens lens suitable for a wide temperature field according to claim 1, characterized in that: The rear infrared lens assembly (4) further includes a sixth infrared lens frame (22), a sixth spacer (23), a rear infrared lens barrel baffle (24), and a rear infrared lens barrel (25); wherein, The sixth infrared lens (21) is disposed within the sixth infrared lens frame (22); The sixth infrared lens frame (22) is disposed inside the rear infrared lens tube (25) via the sixth spacer (23); The rear infrared lens tube baffle (24) is disposed on the front end frame of the rear infrared lens tube (25).

5. The variable-focus infrared lens lens suitable for a wide temperature field according to claim 1, characterized in that: The infrared filter switching assembly (6) includes a first infrared filter (38), a second infrared filter (39), a first infrared filter frame (40), a second infrared filter frame (41), and an infrared filter switching mechanism (42); wherein, The first infrared filter (38) is disposed within the first infrared filter frame (40); The second infrared filter (39) is disposed within the second infrared filter frame (41); The first infrared filter frame (40) is connected to one swing arm of the infrared filter switching mechanism (42); The second infrared filter frame (41) is connected to another swing arm of the infrared filter switching mechanism (42).

6. The variable-focus infrared lens lens suitable for a wide temperature field according to claim 2, characterized in that: The first and second surfaces of the infrared color separator (7) are both planar. The first surface of the infrared color separator (7) is a reflective surface, which can reflect light except for the 1500~1700nm spectrum, with a reflectivity ≥99%. The second surface of the infrared color separator (7) is a transmissive surface, which can transmit light in the 1500~1700nm spectrum, with a transmittance ≥98%.

Images