High-integration-level far infrared optical system and high-integration-level far infrared optical lens

Abstract

The invention discloses a high-integration-level far-infrared optical system and a high-integration-level far-infrared optical lens. The high-integration-level far-infrared optical system sequentially comprises a refraction lens and a combined lens from an object side to an image side along an optical axis. The refractive lens has positive focal power, and the object side surface and the image side surface of the refractive lens both protrude towards the object side. The focal power of the combined lens is positive, the combined lens comprises a lens body and a micro-nano structure array, the lens body comprises a first surface and a second surface which are located on the object side face and the image side face of the lens body respectively, the micro-nano structure array is arranged on any one of the first surface and the second surface, and the other one of the first surface and the second surface is a curved surface. According to the combined lens, broadband spectrum achromatism can be achieved, aberration of the far-infrared optical system can be corrected, due to the fact that the combined lens has the high integration level, the high-integration-level far-infrared optical system still has the excellent imaging quality while the number of lenses used by the high-integration-level far-infrared optical system is small, and the cost and the size of the system can be further reduced.

Description

Technical Field

[0001] The present application relates to the field of far-infrared optical systems, and in particular to a highly integrated far-infrared optical system and a highly integrated far-infrared optical lens. Background Art

[0002] In the prior art, the imaging quality of far-infrared optical systems is usually positively correlated with the cost. In the field of far-infrared optical systems, in order to obtain excellent imaging quality, the following methods are usually adopted: (1) Using lenses made of materials with excellent optical properties to reduce chromatic aberration and spherical aberration, but the cost of materials with excellent optical properties is usually high, resulting in a high cost of the optical system. (2) Adding lenses or lens groups to correct various aberrations, such as chromatic aberration, distortion, field curvature, etc., to improve imaging quality. Increasing the number of lenses will lead to a significant increase in cost and volume, and increasing the number of lenses will significantly increase the difficulty of assembly and calibration. (3) Using a large number of aspherical lenses to effectively reduce aberrations, but aspherical lenses are difficult to process, which will also increase costs.

[0003] Existing far-infrared optical systems typically fail to balance low cost and high image quality, two key considerations for their widespread adoption. Amidst fierce competition, there is an urgent need for a far-infrared optical system that is compact, low-cost, and offers excellent optical performance. Summary of the Invention

[0004] In response to the above technical problems, the embodiments of the present application provide a highly integrated far-infrared optical system and a highly integrated far-infrared optical lens, aiming to provide a far-infrared optical system with a small size, low cost and excellent optical performance.

[0005] According to one aspect of an embodiment of the present application, a highly integrated far-infrared optical system is disclosed, which includes, along the optical axis from the object side to the image side, a refractive lens and a combined lens;

[0006] The refractive power of the refractive lens is positive, the object-side surface of the refractive lens is convex toward the object side, and the image-side surface of the refractive lens is convex toward the object side;

[0007] The optical focal length of the combined lens is positive, and the combined lens includes a lens body and a micro-nano structure array. The lens body includes a first surface and a second surface, the first surface is located on the object side of the lens body, and the second surface is located on the image side of the lens body; the micro-nano structure array is arranged on any one of the first surface and the second surface, and the other of the first surface and the second surface is a curved surface.

[0008] In some embodiments, the curved surface is a spherical surface or an aspherical surface.

[0009] In some embodiments, the refractive lens is a spherical lens or an aspherical lens.

[0010] In some embodiments, the highly integrated far-infrared optical system meets the following requirements: 0.6mm -1 <n1×(|c1|+|c2|)<1.0mm -1 , wherein n1 is the refractive index of the refractive lens, c1 is the curvature of the object side surface of the refractive lens, and c2 is the curvature of the image side surface of the refractive lens.

[0011] In some embodiments, the highly integrated far-infrared optical system satisfies: Among them, f m is the focal length of the micro-nanostructure array of the combined lens, and f is the effective focal length of the highly integrated far-infrared optical system.

[0012] In some embodiments, the highly integrated far-infrared optical system satisfies: Among them, f2 is the focal length of the combined lens, and f is the effective focal length of the highly integrated far-infrared optical system.

[0013] In some embodiments, the highly integrated far-infrared optical system satisfies: Among them, f2 is the focal length of the combined lens, f1 is the focal length of the refractive lens, and f is the effective focal length of the highly integrated far-infrared optical system.

[0014] In some embodiments, the highly integrated far-infrared optical system satisfies: Wherein, L1 is the distance between the object side surface of the refractive lens and the image side surface of the combined lens on the optical axis, and TTL is the total optical length of the highly integrated far-infrared optical system.

[0015] In some embodiments, the highly integrated far-infrared optical system satisfies: Among them, Φ2 is the optical power of the combined lens, T2 is the center thickness of the combined lens, Φ1 is the optical power of the refractive lens, and T1 is the center thickness of the refractive lens.

[0016] In some embodiments, the highly integrated far-infrared optical system satisfies: in, is the average value of the focal length of the refractive lens and the focal length of the combined lens, f1 is the focal length of the refractive lens, and f2 is the focal length of the refractive lens.

[0017] In some embodiments, the highly integrated far-infrared optical system satisfies: Among them, D max D is the maximum effective diameter of the larger one of the refractive lens and the combined lens,min It is the maximum effective diameter of the smaller one between the refractive lens and the combined lens.

[0018] A second aspect of an embodiment of the present application provides a highly integrated far-infrared optical lens, comprising: an imaging detector and a highly integrated far-infrared optical system as described above, wherein the imaging detector is arranged on the image plane of the highly integrated far-infrared optical system.

[0019] The highly integrated far-infrared optical system provided by the present application includes a refractive lens and a combined lens. The optical power of the refractive lens is positive, the object side surface of the refractive lens is convex toward the object side, and the image side surface of the refractive lens is convex toward the object side. The optical power of the combined lens is positive, and the combined lens includes a lens body and a micro-nano structure array. The lens body includes a first surface and a second surface, the first surface is located on the object side surface of the lens body, and the second surface is located on the image side surface of the lens body; the micro-nano structure array is arranged on any one of the first surface and the second surface, and the other of the first surface and the second surface is a curved surface. In the present application, the combined lens can achieve wide-spectrum achromatism and correct the aberrations of the far-infrared optical system, which can ensure that the far-infrared optical system has excellent imaging quality and a smaller volume. Since the combined lens has a high degree of integration, the highly integrated far-infrared optical system provided by the present application uses fewer lenses, which is conducive to further reducing the cost and volume of the highly integrated far-infrared optical system. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The above and other objects, features and advantages of the present application will become more apparent by describing in detail example embodiments thereof with reference to the attached drawings.

[0021] Figure 1 A schematic diagram of the architectural layout of a highly integrated far-infrared optical system in one embodiment of the present application is shown.

[0022] Figure 2 The figure shows the phase distribution diagram of the metasurface in a highly integrated far-infrared optical system in one embodiment of the present application.

[0023] Figure 3 The MTF field of view curve of the highly integrated far-infrared optical system in one embodiment of the present application is shown.

[0024] Figure 4 A schematic diagram of the architectural layout of a highly integrated far-infrared optical system in one embodiment of the present application is shown.

[0025] Figure 5 The figure shows the phase distribution diagram of the metasurface in a highly integrated far-infrared optical system in one embodiment of the present application.

[0026] Figure 6The MTF field of view curve of the highly integrated far-infrared optical system in one embodiment of the present application is shown.

[0027] Figure 7 A schematic diagram of the architectural layout of a highly integrated far-infrared optical system in one embodiment of the present application is shown.

[0028] Figure 8 The figure shows the phase distribution diagram of the metasurface in a highly integrated far-infrared optical system in one embodiment of the present application.

[0029] Figure 9 The MTF field of view curve of the highly integrated far-infrared optical system in one embodiment of the present application is shown.

[0030] Figure 10 A schematic diagram of the architectural layout of a highly integrated far-infrared optical system in one embodiment of the present application is shown.

[0031] Figure 11 The figure shows the phase distribution diagram of the metasurface in a highly integrated far-infrared optical system in one embodiment of the present application.

[0032] Figure 12 The MTF field of view curve of the highly integrated far-infrared optical system in one embodiment of the present application is shown.

[0033] Figure 13 A schematic diagram of the architectural layout of a highly integrated far-infrared optical system in one embodiment of the present application is shown.

[0034] Figure 14 The figure shows the phase distribution diagram of the metasurface in a highly integrated far-infrared optical system in one embodiment of the present application.

[0035] Figure 15 The figure shows the phase distribution diagram of the metasurface in a highly integrated far-infrared optical system in one embodiment of the present application.

[0036] Figure 16 The MTF field of view curve of the highly integrated far-infrared optical system in one embodiment of the present application is shown.

[0037] Reference numerals

[0038] 100. Highly integrated far-infrared optical system;

[0039] 10. Refractive lens;

[0040] 20. Combined lens; 210. Lens body; 210a. First surface; 210b. Second surface; 220. Micro-nanostructure array; 220a. Micro-nanostructure;

[0041] 30. Protective glass;

[0042] 40. Object plane; 50. Image plane; 60. Optical axis. DETAILED DESCRIPTION

[0043] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in a variety of forms and should not be construed as limited to the examples set forth herein; rather, these example embodiments are provided so that the description of this application will be more comprehensive and complete and will fully convey the concepts of the example embodiments to those skilled in the art. The accompanying drawings are merely schematic illustrations of the present application and are not necessarily drawn to scale. Identical reference numerals in the figures indicate identical or similar parts, and thus repeated descriptions thereof will be omitted.

[0044] In addition, the described features, structures or characteristics can be combined in one or more example embodiments in any suitable manner. In the following description, many specific details are provided to provide a full understanding of the example embodiments of the present application. However, those skilled in the art will appreciate that the technical solutions of the present application can be practiced while omitting one or more of the specific details, or other modules, components, etc. can be adopted. In other cases, known structures, methods, implementations or operations are not shown or described in detail to avoid obscuring the main content and making various aspects of the present application vague.

[0045] See also Figure 1 , Figure 1 The following is a schematic diagram illustrating the architectural layout of a highly integrated far-infrared optical system 100 according to one embodiment of the present application. The highly integrated far-infrared optical system 100 comprises, in order from the object side to the image side along the optical axis 60, a refractive lens 10 and a combined lens 20. For ease of description, the surface of each optical element in the highly integrated far-infrared optical system 100 that is closest to the object side along the optical axis 60 is referred to as the object-side surface of the optical element. Similarly, the surface of each optical element in the highly integrated far-infrared optical system 100 that is closest to the image side along the optical axis 60 is referred to as the image-side surface of the optical element. For example, the surface of the refractive lens 10 that is closest to the object side is referred to as the object-side surface of the refractive lens 10, and the surface of the refractive lens 10 that is closest to the image side is referred to as the image-side surface of the refractive lens 10.

[0046] The refractive power of the refractive lens 10 is positive, the object-side surface of the refractive lens 10 is convex toward the object side, and the image-side surface of the refractive lens 10 is convex toward the object side.

[0047] The combined lens 20 has a positive optical power and includes a lens body 210 and a micro-nanostructure array 220. The lens body 210 includes a first surface 210a and a second surface 210b. The first surface 210a is located on the object side of the lens body 210, and the second surface 210b is located on the image side of the lens body 210. That is, the two surfaces of the lens body 210 from the object side to the image side along the optical axis 60 are the first surface 210a and the second surface 210b. The micro-nanostructure array 220 is disposed on either the first surface 210a or the second surface 210b, and the other of the first surface 210a and the second surface 210b is a curved surface. For example, the micro-nanostructure array 220 is disposed on the first surface 210a, and the second surface 210b is a curved surface. Alternatively, the micro-nanostructure array 220 is disposed on the second surface 210b, and the first surface 210a is a curved surface.

[0048] Considering only the side of the combined lens 20 where the micro-nanostructure array 220 is disposed, the micro-nanostructure array 220 and the side of the lens body 210 proximate to the micro-nanostructure array 220 jointly form a metasurface, and this metasurface, formed by the micro-nanostructure array 220 and the side of the lens body 210 proximate to the micro-nanostructure array 220, modulates light. Because the other surface of the combined lens 20 is curved (the surface of the first surface 210a and the second surface 210b where the micro-nanostructure array 220 is not disposed), the other surface of the combined lens 20 also modulates light.

[0049] The micro-nanostructure array 220 is formed by a periodic arrangement of multiple micro-nanostructures 220a. The micro-nanostructures 220a are sub-wavelength structures. The shapes of the micro-nanostructures 220a include but are not limited to nano-cylinders, nano-ring cylinders, nano-circular holes, and nano-ring holes. Figure 1 、 Figure 4 、 Figure 7 、 Figure 10 and Figure 13 In some architectures, the micro-nanostructure 220a is a positive micro-nanostructure; see Figure 14 In some architectures, the micro-nanostructure 220a is a negative micro-nanostructure. It is worth mentioning that Figure 13 and Figure 14 The optical performance of the highly integrated far-infrared optical system 100 shown is the same, and the only difference between the two is the micro-nano structure 220a. Specifically, Figure 13 The micro-nano structure 220a in the highly integrated far-infrared optical system 100 is a positive micro-nano structure. Figure 14The micro-nanostructure 220a in the illustrated highly integrated far-infrared optical system 100 is a negative micro-nanostructure. That is, any highly integrated far-infrared optical system 100 can be implemented using either a positive or negative micro-nanostructure. It should be understood that the micro-nanostructure 220a shown in the various figures of this application is for illustrative purposes only and does not constitute a limitation on parameters such as the positive or negative orientation, shape, characteristic size, and period of the micro-nanostructure 220a. As long as the configured micro-nanostructure 220a has the desired optical performance, it is sufficient.

[0050] Because the micro-nanostructure array 220 of the combined lens 20 possesses a high degree of design freedom, the combined lens 20 also possesses a high degree of design freedom, which translates to greater design options and flexibility for the combined lens 20. Integrating the micro-nanostructure array 220 into the lens body 210 allows the combined lens 20 to achieve a high level of integration while maintaining desired optical performance, thereby reducing the cost of the highly integrated far-infrared optical system 100. Because the micro-nanostructure array 220 can provide varying optical powers for incident light of different wavelengths, wide-spectrum achromatism can be achieved through the rational configuration of various micro-nanostructure parameters. Furthermore, the optical power of the combined lens 20 at each wavelength can be used to correct aberrations within the highly integrated far-infrared optical system 100, ensuring excellent imaging quality for the highly integrated far-infrared optical system 100.

[0051] The highly integrated far-infrared optical system 100 provided herein includes a refractive lens 10 and a combined lens 20. The combined lens 20 achieves wide-spectrum achromatism and corrects aberrations in the highly integrated far-infrared optical system 100, ensuring excellent imaging quality and a compact size. Due to the high level of integration of the combined lens 20, the highly integrated far-infrared optical system 100 provided herein utilizes fewer lens elements, further reducing the cost and size of the highly integrated far-infrared optical system 100.

[0052] In some embodiments, the micro-nanostructure array 220 is disposed on any one of the first surface 210a and the second surface 210b, and the other one of the first surface 210a and the second surface 210b is a curved surface that is convex toward the object side.

[0053] In some embodiments, the micro-nanostructure array 220 is disposed on any one of the first surface 210a and the second surface 210b, and the other one of the first surface 210a and the second surface 210b is a curved surface that is convex toward the image side.

[0054] In some embodiments, the micro-nanostructure array 220 is disposed on any one of the first surface 210a and the second surface 210b, and the other of the first surface 210a and the second surface 210b is a curved surface, which is a spherical surface. In this case, the combined lens has the advantages of low processing cost and good machinability.

[0055] In some embodiments, the micro-nanostructure array 220 is disposed on any one of the first surface 210a and the second surface 210b, and the other of the first surface 210a and the second surface 210b is a curved surface, which is an aspherical surface. In this case, the combined lens has better optical performance and can fully correct the aberration of the highly integrated far-infrared optical system 100.

[0056] In some embodiments, the micro-nanostructure array 220 is disposed on any one of the first surface 210 a and the second surface 210 b , and the surface of the micro-nanostructure array 220 is configured as a plane, thereby reducing the difficulty of processing the micro-nanostructure array 220 .

[0057] In one embodiment, the micro-nanostructure array 220 is disposed on the first surface 210 a , the second surface 210 b is a curved surface, and the second surface 210 b is an aspherical surface.

[0058] In some embodiments, a micro-nanostructure is machined onto one surface of a blank (including but not limited to a planar lens) using a semiconductor process to obtain a micro-nanostructure array 220. On this basis, the surface opposite the surface where the micro-nanostructure array 220 is located is then machined using methods including but not limited to molding, single-point turning, photolithography, and other processes to impart a target curvature to the surface opposite the surface where the micro-nanostructure array 220 is located, thereby obtaining a composite lens 20. It will be appreciated that when the lens body 210 and the micro-nanostructure are made of the same material, the lens body 210 and the micro-nanostructure are an integrally molded structure.

[0059] In some embodiments, a micro-nanostructure array 220 is fabricated from a wafer to form a metalens, and a lens body 210 is fabricated separately. The metalens and lens body 210 are then glued together to form a composite lens 20.

[0060] In some embodiments, the refractive lens 10 is a spherical lens. In this case, the cost of the highly integrated far-infrared optical system 100 can be further reduced.

[0061] In some embodiments, the refractive lens 10 is an aspheric lens. In this case, the highly integrated far-infrared optical system 100 has better performance in aberration control, and can enable the highly integrated far-infrared optical system 100 to have relatively excellent imaging quality.

[0062] In some embodiments, the highly integrated far-infrared optical system 100 satisfies the first condition: 0.6 mm -1 <n1×(|c1|+|c2|)<1.0mm -1 , where n1 is the refractive index of the refractive lens 10 under light of 10.6 micron wavelength, c1 is the curvature of the object side of the refractive lens 10, and c2 is the curvature of the image side of the refractive lens 10. The dimensions of c1 and c2 are both the negative first power of the length unit, for example, mm -1 .

[0063] In the present application, the refractive lens 10 as a whole exhibits a meniscus shape convex toward the object side, and its optical power is positive. Conditional Equation 1 reflects the divergence capability of the refractive lens 10 for light. The lower limit of Conditional Equation 1 ensures that when the refractive index of the refractive lens 10 is relatively low, the absolute value of the optical power of the refractive lens 10 remains as expected. The upper limit of Conditional Equation 1 ensures that when the refractive index of the refractive lens 10 is relatively high, the curvature of the refractive lens 10 is not excessively large, thereby ensuring that the refractive lens 10 has good machinability.

[0064] In some embodiments, the highly integrated far-infrared optical system 100 satisfies Conditional Formula 2: Among them, f m is the focal length of the micro-nanostructure array 220 of the combined lens 20, that is, f m is the focal length of the metasurface formed by the micro-nanostructure array 220 and the lens body 210. f is the effective focal length of the highly integrated far-infrared optical system 100. m , f have the same dimension, both are length units, such as millimeters.

[0065] Conditional equation 2 reflects the focal length contribution of the micro-nanostructure array 220 in the highly integrated far-infrared optical system 100. In other words, Conditional equation 2 reflects the focusing contribution of the micro-nanostructure array 220. The lower limit of Conditional equation 2 represents the maximum light focusing capability that the micro-nanostructure array 220 can provide in the highly integrated far-infrared optical system 100, while the upper limit of Conditional equation 2 represents the minimum light focusing capability that the micro-nanostructure array 220 needs to provide in the highly integrated far-infrared optical system 100.

[0066] In some embodiments, the highly integrated far-infrared optical system 100 satisfies Condition 3: Wherein, f2 is the focal length of the combined lens 20, and f is the effective focal length of the highly integrated far-infrared optical system 100. f2 and f have the same dimension, both being length units, such as millimeters.

[0067] Conditional equation 3 reflects the focal length contribution of the combined lens 20 within the highly integrated far-infrared optical system 100, demonstrating the focusing contribution of the combined lens 20. The lower limit of Conditional equation 3 represents the maximum light focusing capability that the combined lens 20 can provide within the highly integrated far-infrared optical system 100, while the upper limit of Conditional equation 3 represents the minimum light focusing capability that the combined lens 20 must provide within the highly integrated far-infrared optical system 100.

[0068] In some embodiments, the highly integrated far-infrared optical system 100 satisfies Condition 4: Wherein, f2 is the focal length of the combined lens 20, f1 is the focal length of the refractive lens 10, and f is the effective focal length of the highly integrated far-infrared optical system 100. f2, f1, and f have the same dimension, which is a length unit, such as millimeters.

[0069] Conditional Equation 4 reflects the focal length distribution of the combined lens 20 and the refractive lens 10 in the highly integrated far-infrared optical system 100. Since lenses with smaller focal lengths are more sensitive to tolerances, a reasonable focal length distribution can help improve the assembly difficulty and assembly yield of the highly integrated far-infrared optical system 100. The lower limit of Conditional Equation 4 represents the most even distribution of focal lengths between the combined lens 20 and the refractive lens 10 in the highly integrated far-infrared optical system 100, while the upper limit of Conditional Equation 4 represents the most variable distribution of focal lengths between the combined lens 20 and the refractive lens 10 in the highly integrated far-infrared optical system 100.

[0070] In some embodiments, the highly integrated far-infrared optical system 100 satisfies Condition 5: Wherein, L1 is the distance between the object side surface of the refractive lens 10 and the image side surface of the combined lens 20 on the optical axis 60, and TTL is the total optical length of the highly integrated far-infrared optical system 100. L1 and TTL have the same dimension, both of which are length units, such as millimeters.

[0071] In the highly integrated far-infrared optical system 100, the distance L1 between the object side surface of the refractive lens 10 and the image side surface of the combined lens 20 on the optical axis 60 directly affects the mechanical length of the lens corresponding to the highly integrated far-infrared optical system 100. The lower limit of Conditional Formula 5 represents the minimum length ratio of the distance L1 between the object side surface of the refractive lens 10 and the image side surface of the combined lens 20 on the optical axis 60 in the lens corresponding to the highly integrated far-infrared optical system 100. In other words, the lower limit of Conditional Formula 5 represents the limit for compressing the mechanical length of the lens corresponding to the highly integrated far-infrared optical system 100. The lower limit of Conditional Formula 5 represents the maximum length ratio of the distance L1 between the object side surface of the refractive lens 10 and the image side surface of the combined lens 20 on the optical axis 60 in the lens corresponding to the highly integrated far-infrared optical system 100.

[0072] In some embodiments, the highly integrated far-infrared optical system 100 satisfies Condition 6: Wherein, Φ2 is the focal length of the combined lens 20, and Φ1 is the focal length of the refractive lens 10. The unit of Φ2 and Φ1 is D (Dioptre, abbreviated as D, diopter), D=m -1 T2 is the center thickness of the combined lens 20, that is, T2 is the thickness of the combined lens 20 along the optical axis 60. T1 is the center thickness of the refractive lens 10, that is, T1 is the thickness of the refractive lens 10 along the optical axis 60. T2 and T1 have the same dimension, both being length units, such as millimeters.

[0073] Conditional equation 6 reflects the difference between the ratio of the optical power to center thickness of the combined lens 20 and the ratio of the optical power to center thickness of the refractive lens 10. Conditional equation 6 demonstrates the thickness advantage of the combined lens 20 over conventional lenses in providing the same optical power within the same highly integrated far-infrared optical system 100. Specifically, the combined lens has a smaller thickness when providing the same optical power. The lower limit of conditional equation 6 represents the case where the difference between the ratio of the optical power to center thickness of the combined lens 20 and the ratio of the optical power to center thickness of the refractive lens 10 is minimized within the highly integrated far-infrared optical system 100. The upper limit of conditional equation 6 represents the case where the difference between the ratio of the optical power to center thickness of the combined lens 20 and the ratio of the optical power to center thickness of the refractive lens 10 is maximized within the highly integrated far-infrared optical system 100.

[0074] In some embodiments, the highly integrated far-infrared optical system 100 satisfies Condition 7: in, is the average of the focal length of the refractive lens and the focal length of the combined lens. When i = 1, f i =f1, f1 is the focal length of the refractive lens; when i=2, f i =f2, f2 is the focal length of the combined lens. have the same dimension, both are units of length, such as millimeters.

[0075] Equation 7 reflects the uniformity of focal length distribution across the lenses in the highly integrated far-infrared optical system 100. Uneven focal length distribution can easily lead to issues with lens machinability and tolerance sensitivity. The upper limit of Equation 7 represents the maximum focal length unevenness that the highly integrated far-infrared optical system 100 can tolerate, while the lower limit represents the optimal focal length uniformity that the highly integrated far-infrared optical system 100 can provide. At this value, each lens in the highly integrated far-infrared optical system 100 exhibits excellent machinability and tolerance sensitivity, reducing tolerance requirements during assembly.

[0076] In some embodiments, the highly integrated far-infrared optical system 100 satisfies Conditional Equation 8: Among them, D max D is the largest effective diameter of the refractive lens or the combined lens, min The maximum effective diameter of the smaller of the maximum effective diameters of the refractive lens and the combined lens. In this application, the maximum effective diameter of a lens is the larger of the maximum light-transmitting area diameter of the object side of the corresponding lens and the maximum light-transmitting area diameter of the image side of the corresponding lens. For example, if the maximum light-transmitting area diameter of the object side of the refractive lens 10 is a mm, and the maximum light-transmitting area diameter of the object side of the image side of the refractive lens 10 is b mm, and a is greater than b, then the maximum effective diameter of the refractive lens 10 is a mm. max 、D min have the same dimension, both are units of length, such as millimeters.

[0077] When a light beam enters the highly integrated far-infrared optical system 100, its diameter changes as it propagates. A larger value in Conditional Equation 8 results in a more dramatic change in beam diameter, which can easily lead to problems such as tolerance sensitivity and stray light. Therefore, the value of Conditional Equation 8 indirectly reflects the actual performance of the highly integrated far-infrared optical system 100. The upper limit of Conditional Equation 8 represents the maximum allowable diameter change for the highly integrated far-infrared optical system 100, while the lower limit represents the required beam diameter change for the highly integrated far-infrared optical system 100 to achieve its target optical performance.

[0078] See also Figure 1 、 Figure 4 、 Figure 7 、 Figure 10 、 Figure 13 and Figure 14 In some embodiments, the highly integrated far-infrared optical system 100 further includes a protective glass 30 , which is disposed on the object side of the combined lens 20 . The protective glass 30 can reduce the risk of damage to an imaging detector matched with the highly integrated far-infrared optical system 100 .

[0079] The present application exemplarily provides five highly integrated far-infrared optical systems 100 that meet usage requirements in five embodiments. Next, the highly integrated far-infrared optical systems 100 provided in each embodiment of the present application are introduced in detail.

[0080] Example 1

[0081] Figure 1 FIG. 1 shows a schematic diagram of the architecture layout of the highly integrated far-infrared optical system 100 provided in Example 1. Figure 1The medium-to-high-integration far-infrared optical system 100 comprises, in order from the object plane 40 to the image plane 50 along the optical axis 60, a refractive lens 10, a composite lens 20, and a protective glass 30. The refractive lens 10 is an aspherical lens. The micro-nanostructure array 220 of the composite lens 20 is disposed on the first surface 210a of the lens body 210, and the second surface 210b of the lens body 210 is also aspherical. Some parameters of the highly integrated far-infrared optical system 100 provided in Example 1 are shown in Table 1-1.

[0082] Table 1-1. Partial parameters of the highly integrated far-infrared optical system 100 provided in Example 1

[0083] parameter data Total optical length (TTL) 12.6mm Maximum field of view (2ω) 21.7° F-number 0.9 Effective focal length 9.4mm Working band 8μm-12μm

[0084] As shown in Table 1-1, the total optical length of the highly integrated far-infrared optical system 100 is 12.6 mm, which is relatively short. Therefore, the highly integrated far-infrared optical system 100 provided in Example 1 is relatively compact. The F-number of the highly integrated far-infrared optical system 100 is 0.9, allowing for a large amount of light to enter.

[0085] Starting from the object plane 40 and along the optical axis 60 from the object plane 40 to the image plane 50, each surface in the highly integrated far-infrared optical system 100 is numbered, and the parameters of each surface are summarized to obtain the following Table 1-2.

[0086] Table 1-2. Parameters of various surfaces in the highly integrated far-infrared optical system 100 provided in Example 1

[0087]

[0088] For each surface in Table 1-2, surface 1 is the surface of refractive lens 10 near the object side, surface 2 is the surface of refractive lens 10 near the image side. Surface 3 is the surface of combined lens 20 near the object side. Since micro-nanostructure 220a is provided on surface 3, surface 3 is referred to as the structure surface. Surface 4 is the surface of combined lens 20 near the image side. Surface 5 is the surface of protective glass 30 near the object side, surface 6 is the surface of protective glass 30 near the image side, and surface 7 is the image surface 50.

[0089] As shown in Table 1-2, the radius of curvature of surface 1 is 7.4 mm, the distance between surfaces 1 and 2 is 2.6 mm, and the material between surfaces 1 and 2 is IRG206, a chalcogenide glass. The radius of curvature of surface 2 is 8.0 mm, the distance between surfaces 2 and 3 is 4.5 mm, and the material between surfaces 2 and 3 is air. The radius of curvature of surface 3 is infinite, meaning that surface 3 is flat, and the material between surfaces 3 and 4 is silicon. The radius of curvature of surface 4 is -74.2 mm, the distance between surfaces 4 and 5 is 4.4 mm, and the material between surfaces 4 and 5 is air. The radius of curvature of surface 5 is infinite, meaning that surface 5 is flat, the distance between surfaces 5 and 6 is 0.7 mm, and the material between surfaces 5 and 6 is silicon. The radius of curvature of surface 6 is infinite, meaning that surface 6 is flat, the distance between surfaces 6 and 7 is 0.1 mm, and the material between surfaces 6 and 7 is air.

[0090] Surface 1, surface 2, and surface 4 are even-order aspheric surfaces, and their surface shapes satisfy the following relationship:

[0091]

[0092] Where Z(r) is the distance from the aspheric vertex to the aspheric surface at a height r along the optical axis 60 degrees; c is the aspheric surface curvature, c = 1 / R, where R is the aspheric radius of curvature; K is the conic coefficient; and A, B, C, D, etc. are the aspheric coefficients. The values of K, A, B, C, D, etc. for Surfaces 1, 2, and 4 can be found in Tables 1-3.

[0093] Table 1-3. Coefficients of the even-order aspheric surfaces in the highly integrated far-infrared optical system 100 provided in Example 1

[0094] Surface serial number K A B C D E F G 1 -20.1 4.6E-03 -3.5E-04 2.1E-05 -8.6E-07 2.1E-08 -2.7E-10 1.3E-12 2 -21.5 4.5E-03 -3.5E-04 1.8E-05 -3.8E-07 -2.1E-08 1.3E-09 -2.0E-11 4 -125.9 9.5E-05 1.2E-04 -4.8E-05 6.5E-06 -4.4E-07 8.9E-09 2.4E-10

[0095] Refer to Table 1-3. For surface 1, K is -20.1, A is 4.6E-03, B is -3.5E-04, C is 2.1E-05, D is -8.6E-07, E is 2.1E-08, F is -2.7E-10, and G is 1.3E-12. The even-order aspheric coefficients for surfaces 2 and 4 can be found in Table 1-3 with reference to surface 1 and will not be detailed here.

[0096] In this application, the micro-nanostructure array 220 and the lens body 210 together form a metasurface. Figure 2 , Figure 2 : shows the phase distribution diagram of the metasurface in the highly integrated far-infrared optical system 100 provided in Example 1, Figure 2 The middle horizontal axis represents the distance from the center of the metasurface, Figure 2The vertical axis represents the phase. Figure 2 It can be seen that the absolute value of the maximum phase difference of the metasurface is 12.8×2πrad. It is worth mentioning that Figure 2 The actual phase distribution of the metasurface in Example 1 is given. Since the phase is a periodic function about 2π, there is a relationship: (n is an integer), so it can be based on Figure 2 The phase of the metasurface in Example 1 is modulo 2π to achieve normalization processing to meet the needs of actual metasurface processing.

[0097] See also Figure 3 , Figure 3 The MTF (Modulation Transfer Function, MTF for short) field of view curve of the highly integrated far-infrared optical system 100 provided in Example 1 is shown. Figure 3 The horizontal axis is the X-axis field of view angle, and its unit is degree; Figure 3 The vertical axis is the MTF value. Figure 3 The sagittal curve S1 and the meridional curve T1 of the MTF with 21lp / mm spatial frequency as the field of view changes, and the sagittal curve S2 and the meridional curve T2 of the MTF with 42lp / mm spatial frequency as the field of view changes are listed in the table. Figure 3 It can be seen that within the 0.9 field of view (9.76°), the MTF is greater than 0.4, and within the 1.0 field of view (10.85°), the MTF is greater than 0.38. The highly integrated far-infrared optical system 100 has excellent imaging quality.

[0098] Example 2

[0099] Figure 4 FIG. 1 shows a schematic diagram of the architecture layout of the highly integrated far-infrared optical system 100 provided in Example 2. Figure 4 The medium-to-high-integration far-infrared optical system 100 comprises, in order from the object plane 40 to the image plane 50 along the optical axis 60, a refractive lens 10, a composite lens 20, and a protective glass 30. The refractive lens 10 is an aspherical lens. The micro-nanostructure array 220 of the composite lens 20 is disposed on the first surface 210a of the lens body 210, and the second surface 210b of the lens body 210 is also aspherical. Some parameters of the highly integrated far-infrared optical system 100 provided in Example 2 are shown in Table 2-1.

[0100] Table 2-1. Partial parameters of the highly integrated far-infrared optical system 100 provided in Example 2

[0101] parameter data Total optical length (TTL) 12.8mm Maximum field of view (2ω) 21.7° F-number 0.9 Effective focal length 9.7mm Working band 8μm-12μm

[0102] As shown in Table 2-1, the total optical length of the highly integrated far-infrared optical system 100 is 12.8 mm, which is relatively short. Therefore, the highly integrated far-infrared optical system 100 provided in Example 2 is relatively compact. The F-number of the highly integrated far-infrared optical system 100 is 0.9, allowing for a large amount of light to enter.

[0103] Starting from the object plane 40 and along the optical axis 60 from the object plane 40 to the image plane 50, each surface in the highly integrated far-infrared optical system 100 is numbered, and the parameters of each surface are summarized to obtain the following Table 2-2.

[0104] Table 2-2. Parameters of various surfaces in the highly integrated far-infrared optical system 100 provided in Example 2

[0105]

[0106]

[0107] The analysis of each surface in Table 2-2 can refer to Example 1, and no further analysis is performed in this example.

[0108] Surface 1, surface 2, and surface 4 are even-order aspheric surfaces, and their surface shapes satisfy the following relationship:

[0109]

[0110] Where Z(r) is the distance from the aspheric vertex to the aspheric surface at a height r along the optical axis 60°; c is the aspheric surface curvature, c = 1 / R, where R is the aspheric radius of curvature; K is the conic coefficient; and A, B, C, D, etc. are the aspheric coefficients. The values of K, A, B, C, D, etc. for Surfaces 1, 2, and 4 can be found in Table 2-3.

[0111] Table 2-3. Coefficients of the even-order aspheric surfaces in the highly integrated far-infrared optical system 100 provided in Example 2

[0112] Surface serial number K A B C D E F G 1 -14.8 5.0E-03 -3.6E-04 2.1E-05 -8.5E-07 2.1E-08 -2.7E-10 1.1E-12 2 -12.0 5.0E-03 -3.4E-04 1.8E-05 -4.1E-07 -2.2E-08 1.3E-09 -1.7E-11 4 99.6 -2.3E-04 6.9E-05 -4.9E-05 6.5E-06 -4.1E-07 1.1E-08 -1.1E-11

[0113] The even-order aspheric coefficients of surface 1, surface 2 and surface 4 can be obtained from Table 2-3. In this embodiment, the even-order aspheric coefficients of surface 1, surface 2 and surface 4 are not described one by one.

[0114] In this application, the micro-nanostructure array 220 and the lens body 210 together form a metasurface. Figure 5 , Figure 5 : shows the phase distribution diagram of the metasurface in the highly integrated far-infrared optical system 100 provided in Example 2, Figure 5The middle horizontal axis represents the distance from the center of the metasurface, Figure 5 The vertical axis represents the phase. Figure 5 It can be seen that the absolute value of the maximum phase difference of the metasurface is 15×2πrad. It is worth mentioning that Figure 5 The actual phase distribution of the metasurface in Example 2 is given. Since the phase is a periodic function about 2π, there is a relationship: (n is an integer), so it can be based on Figure 5 The phase of the metasurface in Example 2 is modulo 2π to achieve normalization processing to meet the needs of actual metasurface processing.

[0115] See also Figure 6 , Figure 6 The MTF (Modulation Transfer Function, MTF for short) field of view curve of the highly integrated far-infrared optical system 100 provided in Example 2 is shown. Figure 6 The horizontal axis is the X-axis field of view angle, and its unit is degree; Figure 6 The vertical axis is the MTF value. Figure 6 The sagittal curve S1 and the meridional curve T1 of the MTF with 21lp / mm spatial frequency as the field of view changes, and the sagittal curve S2 and the meridional curve T2 of the MTF with 42lp / mm spatial frequency as the field of view changes are listed in the table. Figure 6 It can be seen that within the 0.7 field of view (7.6°), the MTF is greater than 0.4, and within the 1.0 field of view (10.85°), the MTF is greater than 0.35. The highly integrated far-infrared optical system 100 has excellent imaging quality.

[0116] Example 3

[0117] Figure 7 FIG. 1 shows a schematic diagram of the architecture layout of the highly integrated far-infrared optical system 100 provided in Example 3. Figure 7 The medium-to-high-integration far-infrared optical system 100 comprises, in order from the object plane 40 to the image plane 50 along the optical axis 60, a refractive lens 10, a composite lens 20, and a protective glass 30. The refractive lens 10 is an aspherical lens. The micro-nanostructure array 220 of the composite lens 20 is disposed on the first surface 210a of the lens body 210, and the second surface 210b of the lens body 210 is also aspherical. Some parameters of the highly integrated far-infrared optical system 100 provided in Example 3 are shown in Table 3-1.

[0118] Table 3-1. Partial parameters of the highly integrated far-infrared optical system 100 provided in Example 3

[0119] parameter data Total optical length (TTL) 12.8mm Maximum field of view (2ω) 21.7° F-number 0.9 Effective focal length 9.7mm Working band 8μm-12μm

[0120] As shown in Table 3-1, the total optical length of the highly integrated far-infrared optical system 100 is 12.8 mm, which is relatively short. Therefore, the highly integrated far-infrared optical system 100 provided in Example 3 is relatively compact. The F-number of the highly integrated far-infrared optical system 100 is 0.9, allowing for a large amount of light to enter.

[0121] Starting from the object plane 40 and along the optical axis 60 from the object plane 40 to the image plane 50, each surface in the highly integrated far-infrared optical system 100 is numbered, and the parameters of each surface are summarized to obtain the following Table 3-2.

[0122] Table 3-2. Parameters of various surfaces in the highly integrated far-infrared optical system 100 provided in Example 3

[0123]

[0124]

[0125] The analysis of each surface in Table 3-2 can refer to Example 1, and no further analysis is performed in this example.

[0126] Surface 1, surface 2, and surface 4 are even-order aspheric surfaces, and their surface shapes satisfy the following relationship:

[0127]

[0128] Where Z(r) is the distance from the aspheric vertex to the aspheric surface at a height r along the optical axis 60°; c is the aspheric surface curvature, c = 1 / R, where R is the aspheric radius of curvature; K is the conic coefficient; and A, B, C, D, etc. are the aspheric coefficients. The values of K, A, B, C, D, etc. for Surfaces 1, 2, and 4 can be found in Table 3-3.

[0129] Table 3-3. Coefficients of the even-order aspheric surfaces in the highly integrated far-infrared optical system 100 provided in Example 3

[0130] Surface serial number K A B C D E F G 1 -15.7 4.8E-03 -3.6E-04 2.2E-05 -8.5E-07 2.1E-08 -2.7E-10 1.3E-12 2 -10.1 4.4E-03 -3.3E-04 1.9E-05 -4.0E-07 -2.3E-08 1.3E-09 -1.7E-11 4 100.0 -6.3E-04 1.0E-04 -4.8E-05 6.3E-06 -3.9E-07 1.3E-08 -1.6E-10

[0131] The even-order aspheric coefficients of surface 1, surface 2 and surface 4 can be obtained from Table 3-3. In this embodiment, the even-order aspheric coefficients of surface 1, surface 2 and surface 4 are not described one by one.

[0132] In this application, the micro-nanostructure array 220 and the lens body 210 together form a metasurface. Figure 8 , Figure 8 : shows the phase distribution diagram of the metasurface in the highly integrated far-infrared optical system 100 provided in Example 3, Figure 8 The middle horizontal axis represents the distance from the center of the metasurface, Figure 8 The vertical axis represents the phase. Figure 8 It can be seen that the absolute value of the maximum phase difference of the metasurface is 8.7×2πrad. It is worth mentioning that Figure 8 The actual phase distribution of the metasurface in Example 3 is given. Since the phase is a periodic function about 2π, there is a relationship: (n is an integer), so it can be based on Figure 8 The phase of the metasurface in Example 3 is modulo 2π to achieve normalization processing to meet the needs of actual metasurface processing.

[0133] See also Figure 9 , Figure 9 The MTF (Modulation Transfer Function, MTF for short) field of view curve of the highly integrated far-infrared optical system 100 provided in Example 3 is shown. Figure 9 The horizontal axis is the X-axis field of view angle, and its unit is degree; Figure 9 The vertical axis is the MTF value. Figure 9 The sagittal curve S1 and the meridional curve T1 of the MTF with 21lp / mm spatial frequency as the field of view changes, and the sagittal curve S2 and the meridional curve T2 of the MTF with 42lp / mm spatial frequency as the field of view changes are listed in the table. Figure 9 It can be seen that within the 0.8 field of view (8.68°), the MTF is greater than 0.4, and within the 1.0 field of view (10.85°), the MTF is greater than 0.39. The highly integrated far-infrared optical system 100 has excellent imaging quality.

[0134] Example 4

[0135] Figure 10 FIG. 1 shows a schematic diagram of the architecture layout of the highly integrated far-infrared optical system 100 provided in Example 4. Figure 10 The medium-to-high-integration far-infrared optical system 100 comprises, in order from the object plane 40 to the image plane 50 along the optical axis 60, a refractive lens 10, a composite lens 20, and a protective glass 30. The refractive lens 10 is an aspherical lens. The micro-nanostructure array 220 of the composite lens 20 is disposed on the first surface 210a of the lens body 210, and the second surface 210b of the lens body 210 is also aspherical. Some parameters of the highly integrated far-infrared optical system 100 provided in Example 4 are shown in Table 4-1.

[0136] Table 4-1. Partial parameters of the highly integrated far-infrared optical system 100 provided in Example 4

[0137] parameter data Total optical length (TTL) 12.6mm Maximum field of view (2ω) 21.7° F-number 0.9 Effective focal length 9.4mm Working band 8μm-12μm

[0138] As shown in Table 4-1, the total optical length of the highly integrated far-infrared optical system 100 is 12.6 mm, which is relatively short. Therefore, the highly integrated far-infrared optical system 100 provided in Example 4 is relatively compact. The F-number of the highly integrated far-infrared optical system 100 is 0.9, allowing for a large amount of light to enter.

[0139] Starting from the object plane 40 and along the optical axis 60 from the object plane 40 to the image plane 50, each surface in the highly integrated far-infrared optical system 100 is numbered, and the parameters of each surface are summarized to obtain the following Table 4-2.

[0140] Table 4-2. Parameters of various surfaces in the highly integrated far-infrared optical system 100 provided in Example 4

[0141]

[0142]

[0143] The analysis of each surface in Table 2-2 can refer to Example 1, and no further analysis is performed in this example.

[0144] Surface 1, surface 2, and surface 4 are even-order aspheric surfaces, and their surface shapes satisfy the following relationship:

[0145]

[0146] Where Z(r) is the distance from the aspheric vertex to the aspheric surface at a height r along the optical axis 60°; c is the aspheric surface curvature, c = 1 / R, where R is the aspheric radius of curvature; K is the conic coefficient; and A, B, C, D, etc. are the aspheric coefficients. The values of K, A, B, C, D, etc. for Surfaces 1, 2, and 4 can be found in Table 4-3.

[0147] Table 4-3. Coefficients of the even-order aspheric surfaces in the highly integrated far-infrared optical system 100 provided in Example 4

[0148] Surface serial number K A B C D E F G 1 -20.3 4.5E-03 -3.5E-04 2.1E-05 -8.5E-07 2.1E-08 -2.8E-10 1.4E-12 2 -17.4 4.1E-03 -3.4E-04 1.8E-05 -3.9E-07 -2.0E-08 1.3E-09 -1.9E-11 4 -23.3 5.3E-05 1.4E-04 -4.4E-05 7.1E-06 -5.2E-07 1.3E-08 9.3E-11

[0149] The even-order aspheric coefficients of surface 1, surface 2 and surface 4 can be obtained from Table 4-3. In this embodiment, the even-order aspheric coefficients of surface 1, surface 2 and surface 4 are not described one by one.

[0150] In this application, the micro-nanostructure array 220 and the lens body 210 together form a metasurface. Figure 11 , Figure 11: shows the phase distribution diagram of the metasurface in the highly integrated far-infrared optical system 100 provided in Example 4, Figure 11 The middle horizontal axis represents the distance from the center of the metasurface, Figure 11 The vertical axis represents the phase. Figure 11 It can be seen that the absolute value of the maximum phase difference of the metasurface is 3.1×2πrad. It is worth mentioning that Figure 11 The actual phase distribution of the metasurface in Example 4 is given. Since the phase is a periodic function about 2π, there is a relationship: (n is an integer), so it can be based on Figure 11 The phase of the metasurface in Example 4 is modulo 2π to achieve normalization processing to meet the needs of actual metasurface processing.

[0151] See also Figure 12 , Figure 12 The MTF (Modulation Transfer Function, MTF for short) field of view curve of the highly integrated far-infrared optical system 100 provided in Example 4 is shown. Figure 12 The horizontal axis is the X-axis field of view angle, and its unit is degree; Figure 12 The vertical axis is the MTF value. Figure 12 The sagittal curve S1 and the meridional curve T1 of the MTF with 21lp / mm spatial frequency as the field of view changes, and the sagittal curve S2 and the meridional curve T2 of the MTF with 42lp / mm spatial frequency as the field of view changes are listed in the table. Figure 12 It can be seen that within the 0.9 field of view (9.76°), the MTF is greater than 0.4, and within the 1.0 field of view (10.85°), the MTF is greater than 0.38. The highly integrated far-infrared optical system 100 has excellent imaging quality.

[0152] Example 5

[0153] Figure 13 or Figure 14 The schematic diagram of the architecture layout of the highly integrated far-infrared optical system 100 provided in Example 5 is shown. Figure 13 and Figure 14 The optical performance of the highly integrated far-infrared optical system 100 is the same as that of the conventional one. The only difference between the two is the micro-nano structure 220a. Figure 13 The highly integrated far-infrared optical system 100 is illustrated. Figure 14 The highly integrated far-infrared optical system 100 shown in FIG. Figure 13 The description of the highly integrated far-infrared optical system 100 is omitted here. Figure 13The medium-to-high-integration far-infrared optical system 100 comprises, in order from the object plane 40 to the image plane 50 along the optical axis 60, a refractive lens 10, a composite lens 20, and a protective glass 30. The refractive lens 10 is an aspherical lens. The micro-nanostructure array 220 of the composite lens 20 is disposed on the first surface 210a of the lens body 210, and the second surface 210b of the lens body 210 is also aspherical. Some parameters of the highly integrated far-infrared optical system 100 provided in Example 5 are shown in Table 5-1.

[0154] Table 5-1. Some parameters of the highly integrated far-infrared optical system 100 provided in Example 5

[0155] parameter data Total optical length (TTL) 13.4mm Maximum field of view (2ω) 23° F-number 0.9 Effective focal length 9.4mm Working band 8μm-12μm

[0156] As shown in Table 5-1, the total optical length of the highly integrated far-infrared optical system 100 is 13.4 mm, which is relatively short. Therefore, the highly integrated far-infrared optical system 100 provided in Example 5 is relatively compact. The F-number of the highly integrated far-infrared optical system 100 is 0.9, allowing for a large amount of light to enter.

[0157] Starting from the object plane 40 and along the optical axis 60 from the object plane 40 to the image plane 50, each surface in the highly integrated far-infrared optical system 100 is numbered, and the parameters of each surface are summarized to obtain the following Table 5-2.

[0158] Table 5-2. Parameters of various surfaces in the highly integrated far-infrared optical system 100 provided in Example 5

[0159]

[0160] The analysis of each surface in Table 5-2 can refer to Example 1, and no further analysis is performed in this example.

[0161] Surface 1, surface 2, and surface 4 are even-order aspheric surfaces, and their surface shapes satisfy the following relationship:

[0162]

[0163] Where Z(r) is the distance from the aspheric vertex to the aspheric surface at a height r along the optical axis 60°; c is the aspheric surface curvature, c = 1 / R, where R is the aspheric radius of curvature; K is the conic coefficient; and A, B, C, D, etc. are the aspheric coefficients. The values of K, A, B, C, D, etc. for Surfaces 1, 2, and 4 can be found in Table 5-3.

[0164] Table 5-3. Coefficients of the even-order aspheric surfaces in the highly integrated far-infrared optical system 100 provided in Example 5

[0165] Surface serial number K A B C D E F G 1 -23.0 4.5E-03 -3.6E-04 2.2E-05 -8.6E-07 2.1E-08 -2.8E-10 1.5E-12 2 -13.1 3.8E-03 -3.2E-04 1.7E-05 -4.0E-07 -2.0E-08 1.3E-09 -1.9E-11 4 1.6 -1.4E-04 1.3E-04 -3.5E-05 5.6E-06 -4.9E-07 2.2E-08 -4.0E-10

[0166] The even-order aspheric coefficients of surface 1, surface 2 and surface 4 can be obtained from Table 5-3. In this embodiment, the even-order aspheric coefficients of surface 1, surface 2 and surface 4 are not described one by one.

[0167] In this application, the micro-nanostructure array 220 and the lens body 210 together form a metasurface. Figure 14 , Figure 14 : shows the phase distribution diagram of the metasurface in the highly integrated far-infrared optical system 100 provided in Example 5, Figure 14 The middle horizontal axis represents the distance from the center of the metasurface, Figure 14 The vertical axis represents the phase. Figure 14 It can be seen that the absolute value of the maximum phase difference of the metasurface is 1.8×2πrad. It is worth mentioning that Figure 14 The actual phase distribution of the metasurface in Example 5 is given. Since the phase is a periodic function about 2π, there is a relationship: (n is an integer), so it can be based on Figure 14 The phase of the metasurface in Example 5 is modulo 2π to achieve normalization processing to meet the needs of actual metasurface processing.

[0168] See also Figure 15 , Figure 15 The MTF (Modulation Transfer Function, MTF for short) field of view curve of the highly integrated far-infrared optical system 100 provided in Example 5 is shown. Figure 15 The horizontal axis is the X-axis field of view angle, and its unit is degree; Figure 15 The vertical axis is the MTF value. Figure 15 The sagittal curve S1 and the meridional curve T1 of the MTF with 21lp / mm spatial frequency as the field of view changes, and the sagittal curve S2 and the meridional curve T2 of the MTF with 42lp / mm spatial frequency as the field of view changes are listed in the table. Figure 15 It can be seen that within the 0.9 field of view (10.35°), the MTF is greater than 0.42, and within the 1.0 field of view (11.5°), the MTF is greater than 0.39. The highly integrated far-infrared optical system 100 has excellent imaging quality.

[0169] After summarizing the various parameters of the highly integrated far-infrared optical system 100 provided in the above five embodiments, the following Table 6 is obtained. Table 6 is mainly used to illustrate that the various conditions met by the highly integrated far-infrared optical system 100 provided in this application have been experimentally verified and supported.

[0170] Table 6. Parameters of the highly integrated far-infrared optical system 100 provided in various embodiments

[0171]

[0172]

[0173] The present application also provides a highly integrated far-infrared optical lens (not shown), which includes an imaging detector (not shown) and the highly integrated far-infrared optical system 100. The imaging detector is disposed on the image plane 50 of the highly integrated far-infrared optical system 100. The imaging detector includes, but is not limited to, a CMOS (Complementary Metal Oxide Semiconductor) and a CCD (Charge Coupled Device). The architectural layout of the highly integrated far-infrared optical system 100 can be found above and will not be further described here.

[0174] Those skilled in the art will readily appreciate other embodiments of the present invention after considering the specification and practicing the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of the present invention that follow the general principles of the present invention and include common knowledge or customary techniques in the art not disclosed herein. The description and examples are to be considered merely as exemplary, and the true scope and spirit of the present application are indicated by the appended claims.

Claims

1. A highly integrated far-infrared optical system, characterized in that: The highly integrated far-infrared optical system comprises, in order from the object side to the image side along the optical axis: a refractive lens and a combined lens; The refractive power of the refractive lens is positive, the object-side surface of the refractive lens is convex toward the object side, and the image-side surface of the refractive lens is convex toward the object side; The optical focal length of the combined lens is positive, and the combined lens includes a lens body and a micro-nano structure array. The lens body includes a first surface and a second surface, the first surface is located on the object side of the lens body, and the second surface is located on the image side of the lens body; the micro-nano structure array is arranged on any one of the first surface and the second surface, and the other of the first surface and the second surface is a curved surface.

2. The highly integrated far-infrared optical system according to claim 1, characterized in that: The highly integrated far-infrared optical system meets the following requirements: 0.6mm -1 <n1×(|c1|+|c2|)<1.0mm -1 , wherein n1 is the refractive index of the refractive lens, c1 is the curvature of the object side surface of the refractive lens, and c2 is the curvature of the image side surface of the refractive lens.

3. The highly integrated far-infrared optical system according to claim 1, characterized in that: The highly integrated far-infrared optical system meets the following requirements: Among them, f m is the focal length of the micro-nanostructure array of the combined lens, and f is the effective focal length of the highly integrated far-infrared optical system.

4. The highly integrated far-infrared optical system according to claim 1, characterized in that: The highly integrated far-infrared optical system meets the following requirements: Among them, f2 is the focal length of the combined lens, and f is the effective focal length of the highly integrated far-infrared optical system.

5. The highly integrated far-infrared optical system according to claim 1, characterized in that: The highly integrated far-infrared optical system meets the following requirements: Among them, f2 is the focal length of the combined lens, f1 is the focal length of the refractive lens, and f is the effective focal length of the highly integrated far-infrared optical system.

6. The highly integrated far-infrared optical system according to claim 1, characterized in that: The highly integrated far-infrared optical system meets the following requirements: Wherein, L1 is the distance between the object side surface of the refractive lens and the image side surface of the combined lens on the optical axis, and TTL is the total optical length of the highly integrated far-infrared optical system.

7. The highly integrated far-infrared optical system according to claim 1, characterized in that: The highly integrated far-infrared optical system meets the following requirements: Among them, Φ2 is the optical power of the combined lens, T2 is the center thickness of the combined lens, Φ1 is the optical power of the refractive lens, and T1 is the center thickness of the refractive lens.

8. The highly integrated far-infrared optical system according to claim 1, characterized in that: The highly integrated far-infrared optical system meets the following requirements: in, is the average of the focal lengths of the refractive lens and the combined lens, f1 is the focal length of the refractive lens, and f2 is the focal length of the combined lens.

9. The highly integrated far-infrared optical system according to claim 1, characterized in that: The highly integrated far-infrared optical system meets the following requirements: Among them, D max D is the maximum effective diameter of the larger one of the refractive lens and the combined lens, min It is the maximum effective diameter of the smaller one between the refractive lens and the combined lens.

10. A highly integrated far-infrared optical lens, characterized in that: include: An imaging detector and a highly integrated far-infrared optical system as described in any one of claims 1 to 9, wherein the imaging detector is arranged on the image plane of the highly integrated far-infrared optical system.

Images