Optical lens for temperature drift compensation and method of manufacturing the same

Abstract

The embodiment of the present application provides an optical lens for temperature drift compensation and a manufacturing method thereof. The optical lens comprises: a lens body having a first linear expansion coefficient A; and a compensation element located in the lens body and having a second linear expansion coefficient B; wherein, based on a preset temperature gradient AT, a preset back focus offset AD of the lens body under the preset temperature gradient AT, a preset compensation amount AX of the lens body under the preset temperature gradient AT, the first linear expansion coefficient A and the second linear expansion coefficient B satisfy the following rules: when AT>0, if AD>0 and AX<0, then B<A; if AD>0 and AX>0, then B>A; if AD<0 and AX<0, then B>A; if AD<0 and AX>0, then B<A; when AT<0, if AD>0 and AX<0, then B>A; if AD>0 and AX>0, then B<A; if AD<0 and AX<0, then B>A; and if AD<0 and AX>0, then B

Description

Technical Field

[0001] This application relates to the technical field of optical lenses, and more specifically, to an optical lens for temperature drift compensation and a manufacturing method thereof. Background Art

[0002] Currently, optical lenses are widely used in technical fields such as security monitoring, intelligent transportation, and vehicle autonomous driving. To achieve high imaging quality, for example, large-aperture optical lenses can be used to meet higher shooting requirements. However, for large-aperture optical lenses, it is more difficult to focus a large amount of light on the same point after passing through the optical lens. When the ambient temperature changes, it is easier to cause the phenomenon of defocusing. As the aperture increases, the complexity of the shooting environment increases, and the factors causing defocusing will be correspondingly amplified. The defocusing phenomenon will make it difficult to clearly identify the details of the photographed scene and even more difficult to meet the expected shooting requirements.

[0003] In some related technologies, a temperature-sensitive element can be used to monitor temperature changes to automatically drive the focusing lens group to achieve automatic focusing compensation. However, this method requires adding a temperature-sensitive element in the optical lens, resulting in a relatively high cost. In some other related technologies, the focusing group can be manually driven according to temperature changes to achieve manual focusing compensation. However, for the optical lens after installation and fixation, it is inconvenient to frequently manually adjust the focusing lens group. Summary of the Invention

[0004] Some embodiments of this application provide an optical lens for temperature drift compensation and a manufacturing method thereof, which can at least partially solve the above technical problems or other technical problems.

[0005] Some embodiments of this application provide an optical lens for temperature drift compensation. The optical lens includes: a lens body having a first linear expansion coefficient A; a compensation element located in the lens body and having a second linear expansion coefficient B; wherein, based on a preset temperature gradient △T, a preset back focal shift △D of the lens body under the preset temperature gradient △T, a preset compensation amount △X of the lens body under the preset temperature gradient △T, the first linear expansion coefficient A, and the second linear expansion coefficient B satisfy the following rules: when ΔT > 0, if ΔD > 0 and ΔX < 0, then B < A; if ΔD > 0 and ΔX > 0, then B > A; if ΔD < 0 and ΔX < 0, then B > A; if ΔD < 0 and ΔX > 0, then B < A; when ΔT < 0, if ΔD > 0 and ΔX < 0, then B > A; if ΔD > 0 and ΔX > 0, then B < A; if ΔD < 0 and ΔX < 0, then B > A; and if ΔD < 0 and ΔX > 0, then B < A.

[0006] In some embodiments, the optical lens further includes an elastic element for driving the compensation element to adjust the moving distance of at least part of the lens body in the optical axis direction.

[0007] In some embodiments, the elastic element includes a corrugated shrapnel.

[0008] In some embodiments, the dimension L of the compensation element in the optical axis direction satisfies: L = |ΔX| / (|(B - A)| × ΔT).

[0009] In some embodiments, the compensation coefficient K of the compensation element is related to its position in the lens body, and the compensation coefficient K satisfies: △X = △D × K.

[0010] In some embodiments, the lens body includes at least one lens, and the elastic element is used to drive the compensation element to adjust the position of at least one lens in the optical axis direction.

[0011] Some embodiments of the present application also provide a manufacturing method for an optical lens for temperature drift compensation. The manufacturing method of the optical lens includes: determining the compensation coefficient K and the preset compensation amount △X of the compensation element according to the preset back focal shift amount △D and the position of the compensation element in the lens body, where △X = △D × K; and determining the second linear expansion coefficient B of the compensation element according to the preset temperature gradient △T, the preset back focal shift amount △D, the preset compensation amount △X, and the first linear expansion coefficient A of the lens body according to the following rules: when ΔT > 0, if ΔD > 0 and ΔX < 0, then B < A; if ΔD > 0 and ΔX > 0, then B > A; if ΔD < 0 and ΔX < 0, then B > A; if ΔD < 0 and ΔX > 0, then B < A; when ΔT < 0, if ΔD > 0 and ΔX < 0, then B > A; if ΔD > 0 and ΔX > 0, then B < A; if ΔD < 0 and ΔX < 0, then B > A; and if ΔD < 0 and ΔX > 0, then B < A.

[0012] In some embodiments, the manufacturing method further includes: determining the dimension L of the compensation element in the optical axis direction according to L = |ΔX| / (|(B - A)| × ΔT).

[0013] In some embodiments, the manufacturing method further includes: determining the second linear expansion coefficient B = (|ΔX| / L + (A × ΔT)) / ΔT according to the dimension L of the compensation element in the optical axis direction.

[0014] In some embodiments, the manufacturing method further includes: arranging an elastic element in the lens body, where the elastic element is used to drive the compensation element to adjust the moving distance of at least part of the lens body in the optical axis direction.

[0015] According to an embodiment of this application, an optical lens for temperature drift compensation and its manufacturing method are provided. By reasonably setting the first linear expansion coefficient of the lens body and the second linear expansion coefficient of the compensation element, the actual back focus offset of the lens body can be automatically compensated using the difference between the elongation and / or shortening of the lens body and the compensation element, thereby achieving automatic focusing without frequent manual adjustment. Furthermore, the compensation element can be flexibly positioned relative to the lens body; for example, it can be positioned between adjacent lenses that are sensitive to spacing. This allows for application to the original structural design of the optical lens, and offers strong versatility, simple structure, and low cost. Attached Figure Description

[0016] Other features, objects, and advantages of this application will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0017] Figure 1 This is a block diagram of an optical lens according to an exemplary embodiment of this application;

[0018] Figure 2 This is a cross-sectional view of the structure of an optical lens according to an exemplary embodiment of this application;

[0019] Figure 3 This is a schematic diagram of the structure of an elastic element according to an exemplary embodiment of this application; and

[0020] Figure 4 This is a flowchart of a method for manufacturing an optical lens according to an exemplary embodiment of this application. Detailed Implementation

[0021] To better understand this application, various aspects of this application will be described in more detail with reference to the accompanying drawings. It should be understood that these detailed descriptions are merely illustrative of exemplary embodiments of this application and are not intended to limit the scope of this application in any way. Throughout the specification, the same reference numerals refer to the same elements. The expression "and / or" includes any and all combinations of one or more of the associated listed items.

[0022] It should be noted that in this specification, the terms "first," "second," "third," etc., are used only to distinguish one feature from another and do not imply any limitation on the features, especially not any order of precedence. Therefore, without departing from the teachings of this application, the first linear expansion coefficient discussed herein may also be referred to as the second linear expansion coefficient, and vice versa.

[0023] The terminology used herein is for the purpose of describing particular exemplary embodiments and is not intended to be limiting. When used in this specification, the terms “comprising,” “including,” “including,” and / or “comprising” indicate the presence of the stated features, integrals, elements, components, and / or combinations thereof, but do not exclude the presence of one or more other features, integrals, elements, components, and / or combinations thereof.

[0024] This document describes the embodiments with reference to schematic diagrams of exemplary implementations. The exemplary implementations disclosed herein should not be construed as limited to the specific shapes and sizes shown, but rather include various equivalent structures capable of achieving the same function, as well as shape and size variations arising, for example, during manufacturing. The positions shown in the accompanying drawings are schematic in nature and not intended to limit the positions of the components.

[0025] Unless otherwise specified, all terms used herein (including technical and scientific terms) shall have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains. Terms such as those defined in common dictionaries shall be interpreted as having the meaning consistent with their meaning in the context of the relevant field and shall not be interpreted in an idealized or overly formal sense unless expressly defined herein.

[0026] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. Furthermore, unless explicitly limited or contradicted by the context, the specific steps included in the methods described in this application are not limited to the order in which they are described, but can be performed in any order or in parallel.

[0027] The embodiments of this application will now be described in detail with reference to the accompanying drawings.

[0028] Some embodiments of this application provide an optical lens for temperature drift compensation. Figure 1 This is a block diagram of an optical lens 100 according to an exemplary embodiment of this application. Figure 1 As shown, the optical lens 100 includes a lens body 110 and a compensation element 120.

[0029] In some embodiments, the lens body 110 may include at least one lens (not shown) and a lens barrel (not shown) for housing the at least one lens. For example, the optical lens can have different optical characteristics by setting the number of lenses, optical power, and surface shape. In some examples, multiple lenses may be housed in the same lens barrel, and the material of the lens barrel may have a first linear expansion coefficient A. In other examples, multiple lenses may be divided into several lens groups, each lens group may be housed in its own lens barrel, and the material of these lens barrels may have a first linear expansion coefficient A. It should be noted that the optical lens described in this application may include a fixed-focus optical lens or a zoom optical lens, and there is no limitation herein. For example, when the optical lens is a zoom optical lens, the position of the lens group in the optical axis direction can be adjusted by driving the lens barrel, thereby achieving optical lens zoom.

[0030] The compensation element 120 may be located within the lens body 110. For example, the compensation element 120 may be a ring-shaped structure and located between adjacent lens barrels or between the lens barrel closest to the image side and the photosensitive element 130. It should be noted that the compensation element 120 may also be located at other positions within the lens body, which is not limited herein. The material of the compensation element 120 may have a second linear expansion coefficient B. The second linear expansion coefficient B and the first linear expansion coefficient A may have different values. For example, the first linear expansion coefficient A and the second linear expansion coefficient B may be different from each other by selecting different materials for the lens barrel and the compensation element 120. It should be noted that the linear expansion coefficient indicates the degree of expansion or contraction of a material, specifically referring to the elongation corresponding to each unit increase in temperature or the shortening corresponding to each unit decrease in temperature.

[0031] In some embodiments, the optical lens 100 may further include a photosensitive element 130. The photosensitive element 130 may be located on the image side of the lens body 110. For example, the photosensitive element 130 may include a photocoupled device (CCD) or a complementary metal oxide semiconductor device (CMOS). It should be noted that when the photosensitive element 130 is located at the focal plane of the lens body 110, a clear image can be achieved. When the ambient temperature changes (e.g., the actual current ambient temperature changes relative to the assembly ambient temperature), the actual focal plane of the lens body 110 may deviate from the photosensitive element 130 due to the influence of the linear expansion coefficient of the materials.

[0032] The temperature gradient can be the amount of temperature change. For example, if the ambient temperature during the assembly of the optical lens 100 is T1, and the current ambient temperature during the use of the optical lens is T2, then the temperature gradient ΔT = T1 - T2. The preset temperature gradient ΔT can be a specified temperature gradient. The preset back focus offset ΔD can be the amount of back focus change of the lens body 110 under the preset temperature gradient ΔT. The preset compensation amount ΔX can be the amount of elongation or shortening of the compensation element 120 under the preset temperature gradient ΔT.

[0033] In the optical lens 100, the above-mentioned preset temperature gradient ΔT, preset back focal offset ΔD, preset compensation amount ΔX, first linear expansion coefficient A, and second linear expansion coefficient B satisfy the following rules: When the preset temperature gradient ΔT > 0, for example, when the assembly environment temperature T1 is higher than the preset current environment temperature T2, if ΔD > 0 and ΔX < 0, then B < A; if ΔD > 0 and ΔX > 0, then B > A; if ΔD < 0 and ΔX < 0, then B > A; if ΔD < 0 and ΔX > 0, then B < A. When the preset temperature gradient ΔT < 0, for example, when the assembly environment temperature T1 is lower than the preset current environment temperature T2, if ΔD > 0 and ΔX < 0, then B > A; if ΔD > 0 and ΔX > 0, then B < A; if ΔD < 0 and ΔX < 0, then B > A; if ΔD < 0 and ΔX > 0, then B < A.

[0034] It should be noted that the compensation element 120 is located at different positions of the lens body 110, and the preset back focal offset ΔD and the preset compensation amount ΔX have different ratio relationships. In other words, the preset back focal offset ΔD, the preset compensation amount ΔX, and the compensation coefficient K can satisfy: ΔX = ΔD × K. For example, when the compensation element 120 is located between the lens barrel closest to the image side and the photosensitive element 130, the compensation coefficient K can be 1.

[0035] According to the optical lens provided by the embodiment of the present application, by reasonably setting the first linear expansion coefficient of the lens body and the second linear expansion coefficient of the compensation element, the difference in the elongation amount and / or shortening amount of the lens body and the compensation element can be used to automatically compensate the actual back focal offset of the lens body to achieve automatic focusing, and there is no need for frequent manual adjustment. In addition, the compensation element can be flexibly arranged relative to the lens body. For example, the compensation element can be arranged between adjacent lenses sensitive to intervals, which is applicable to the original structure design of the optical lens, and has strong versatility, simple structure, and low cost.

[0036] In some embodiments, as Figure 1 shown, the optical lens 100 may further include an elastic element 140. For example, the elastic element 140 may include a wave washer. The elastic element 140 can be used to drive the compensation element 120 to adjust the moving distance of at least part of the lens body 110 in the optical axis direction. For example, when the optical lens 100 is at the assembly environment temperature, the elastic element 140 is in a compressed state; when the optical lens 100 is at the actual current environment temperature, the elastic element 140 drives the compensation element 120 to adjust, for example, the moving distance of the lens barrel in the optical axis under the action of elastic force, so as to adjust the position of the lens in the lens barrel in the optical axis to achieve automatic focusing. It should be noted that the type of the elastic element 140 is not limited to the wave washer, and can also be a helical spring, an elastic washer, etc., which are not limited in this application. Using the elastic force and recoverability of the elastic element to drive the compensation element to achieve automatic focusing of the optical lens has a simple structure and low cost.

[0037] In some embodiments, as mentioned above, the compensation element 120 may be, for example, a ring structure. The dimension L of the compensation element 120 in the optical axis direction, the preset temperature gradient ΔT, the preset compensation amount ΔX, the second coefficient of thermal expansion B, and the first coefficient of linear thermal expansion A can satisfy: L=|ΔX| / (|(BA)|×ΔT). By reasonably setting the dimension L of the compensation element in the optical axis direction and the second coefficient of linear thermal expansion B, the dimension of the compensation element in the optical axis direction can be flexibly adjusted, which is beneficial for adapting to the original structural design of the optical lens and has strong versatility.

[0038] Figure 2 This is a cross-sectional view of the structure of an optical lens 200 according to an exemplary embodiment of this application. For example, the optical lens 200 may be a zoom optical lens. The following is in conjunction with... Figure 2 The optical lens 200 of this embodiment will be described in detail.

[0039] The optical lens 200 may include a first lens group 211, a second lens group 212, a third lens group 213, and a fourth lens group 214. The first lens group 211 to the fourth lens group 214 can be housed in their respective lens barrels. Specifically, the first lens group 211 can be housed in the first lens barrel 215, the second lens group 212 in the second lens barrel 216, the third lens group 213 in the third lens barrel 217, and the fourth lens group 214 in the fourth lens barrel 218. The aforementioned first lens group 211 to the fourth lens group 214 and their corresponding first lens barrels 215 to fourth lens barrels 218 can be referred to as the lens body. In this embodiment, a slanted guide groove can be used to slide the second lens barrel 216 relative to the first lens barrel 215, thereby moving the second lens group 212 relative to the first lens group 211 in the optical axis direction to achieve the zoom function of the optical lens.

[0040] The lens body may also include guide pins 251 and a focusing lens barrel 252. Three guide pins 251 are evenly distributed around the outer periphery of the fourth lens barrel 218. The focusing lens barrel 252 is fitted around the outer periphery of the third lens barrel 217. The guide pins 251 can slide in the straight guide groove of the fourth lens barrel 218 along a direction perpendicular to the optical axis. The end of the guide pin 251 away from the optical axis can engage with the oblique guide groove of the focusing lens barrel 252, allowing the guide pin 251 to also slide in the oblique guide groove of the focusing lens barrel 252. In other words, since the guide pins 251 slide in the oblique guide groove of the focusing lens barrel 252 on one hand and in the straight guide groove of the fourth lens barrel 218 on the other, when the focusing lens barrel 252 rotates, the guide pins 251, under the action of the focusing lens barrel 252, drive the fourth lens barrel 218 to move in the optical axis direction, thereby adjusting the position of the fourth lens group 214 in the optical axis direction.

[0041] The compensation element 220 is a ring-shaped structure and is sleeved on the outer periphery of the third lens barrel 217. The end of the compensation element 220 near the image side contacts the end of the focusing lens barrel 252 near the object side. The material of the first lens barrel 215 to the fourth lens barrel 218 can be aluminum alloy A6061. The coefficient of linear expansion (i.e., the first coefficient of linear expansion A) of this material is 2.36 × 10⁻⁶. -5 / ℃. The coefficient of linear expansion (i.e., the second coefficient of linear expansion B) of the material of the compensation element 220 is 1.3 × 10⁻⁶. -4 / ℃, and the dimension L in the optical axis direction is 4.2mm.

[0042] The elastic element 240 is disposed at the end of the focusing lens barrel 252 near the image side. The elastic element 240 may be a wave spring. Figure 3 A schematic diagram of a wave spring is shown. The wave spring can have a compressed state and an extended state, and can switch between the two states under axial force.

[0043] The preset temperature gradient ΔT is 55℃. Since the compensation element 220 adjusts the position of the fourth lens group 214 in the optical axis direction, the adjustment coefficient K can be 1, that is, the preset compensation amount ΔX can be 0.022mm. Without the compensation element 220, the preset back focus offset ΔD of the lens body is 0.022mm.

[0044] In this embodiment, the second linear expansion coefficient B of the compensation element 220 is greater than the first linear expansion coefficient A of the lens body. As the actual ambient temperature gradually decreases, for example, when the actual ambient temperature T2 is -30°C and the assembly ambient temperature T1 is 25°C, the change in the compensation element 220 will always be greater than the change in the lens body. When the actual ambient temperature change is small, the elastic element 240 is in a compressed state. When the actual ambient temperature change is large, the difference in the amount of change between the compensation element 220 and the lens body creates an axial gap between them. Utilizing the recoverability of the elastic element 240 in the compressed state, the focusing lens barrel 252 is moved 0.022mm towards the image side. Simultaneously, under the action of the guide pin 251, the fourth lens barrel 218 is moved 0.022mm towards the image side in the optical axis direction, thereby adjusting the position of the fourth lens group 214 in the optical axis direction to compensate for the change in the lens body and achieve autofocus of the optical lens.

[0045] Some embodiments of this application also provide a method for manufacturing an optical lens for temperature drift compensation. Figure 4 This is a flowchart of a method 400 for manufacturing an optical lens according to an exemplary embodiment of this application. Figure 4 As shown, manufacturing method 400 includes steps 410 and 420. For example, manufacturing method 400 can be used to manufacture the optical lens 100 described above.

[0046] Step 410

[0047] In this step, according to the preset back focal offset ΔD and the position of the compensation element in the lens body, the compensation coefficient K and the preset compensation amount ΔX of the compensation element are determined. Among them, the preset back focal offset ΔD can be the back focal change amount of the lens body 110 under the preset temperature gradient ΔT. When the compensation element is located at different positions in the lens body, the preset back focal offset ΔD and the preset compensation amount ΔX have different ratio relationships. In other words, the compensation coefficient K can be determined according to the position of the compensation element in the lens body, and then the preset compensation amount ΔX = ΔD × K can be determined.

[0048] Step 420

[0049] In this step, according to the preset temperature gradient ΔT, the preset back focal offset ΔD, the preset compensation amount ΔX, and the first linear expansion coefficient A of the lens body, the second linear expansion coefficient B of the compensation element is determined. Among them, the preset back focal offset ΔD and the preset compensation amount ΔX can be obtained in step 410, and the preset temperature gradient ΔT corresponds to the preset back focal offset ΔD. The first linear expansion coefficient A of the lens body can be, for example, the linear expansion coefficient of the lens barrel. The second linear expansion coefficient B of the compensation element can be determined according to the following rules. Specifically, when the preset temperature gradient ΔT > 0, for example, when the assembly environment temperature T1 is higher than the preset current environment temperature T2, if ΔD > 0 and ΔX < 0, then B < A; if ΔD > 0 and ΔX > 0, then B > A; if ΔD < 0 and ΔX < 0, then B > A; if ΔD < 0 and ΔX > 0, then B < A. When the preset temperature gradient ΔT < 0, for example, when the assembly environment temperature T1 is lower than the preset current environment temperature T2, if ΔD > 0 and ΔX < 0, then B > A; if ΔD > 0 and ΔX > 0, then B < A; if ΔD < 0 and ΔX < 0, then B > A; if ΔD < 0 and ΔX > 0, then B < A.

[0050] According to the manufacturing method of the optical lens provided by the embodiment of the present application, by reasonably setting the first linear expansion coefficient of the lens body and the second linear expansion coefficient of the compensation element, the actual back focal offset of the lens body can be automatically compensated by using the difference in the elongation amount and / or shortening amount of the lens body and the compensation element, so as to achieve automatic focusing without frequent manual adjustment. In addition, the compensation element can be flexibly arranged relative to the lens body. For example, the compensation element can be arranged between adjacent lenses sensitive to the interval, which can be applied to the original structure design of the optical lens, and has strong versatility, simple structure, and low cost.

[0051] In some embodiments, the manufacturing method 400 may further include the step of determining the dimension L of the compensation element in the optical axis direction. Specifically, under the premise of satisfying the rule in step 420, the dimension L of the compensation element in the optical axis direction is L = |ΔX| / (|(BA)|×ΔT). By reasonably setting the second linear expansion coefficient, the dimension of the compensation element in the optical axis direction can be flexibly adjusted, which is beneficial for adapting to the original structural design of the optical lens and has strong versatility.

[0052] In some embodiments, based on the specified dimension L of the compensation element in the optical axis direction, the manufacturing method 400 may further include a step of determining a second linear expansion coefficient B according to the specified dimension L of the compensation element in the optical axis direction. Specifically, under the premise of satisfying the rule in step 420, the second linear expansion coefficient B = (|ΔX| / L + (A×ΔT)) / ΔT. By reasonably setting the second linear expansion coefficient, the dimension of the compensation element in the optical axis direction can be flexibly adjusted, which is beneficial for adapting to the original structural design of the optical lens and has strong versatility.

[0053] In some embodiments, the manufacturing method 400 may further include the step of setting an elastic element. The elastic element can be used to drive the compensation element to adjust the movement distance of at least a portion of the lens body in the optical axis direction to achieve autofocus. Utilizing the elasticity and recoverability of the elastic element to drive the compensation element to achieve autofocus of the optical lens results in a simple structure and low cost.

[0054] In some embodiments, manufacturing method 400 can be used to manufacture the optical lens 200 described above. The following is in conjunction with... Figure 2 Provide a detailed description.

[0055] In step 410, the lens body may have Figure 2 The specific structure shown will not be described in detail here. The preset back focus offset ΔD can be 0.022mm, which can be the change in back focus of the lens body under a preset temperature gradient ΔT of 55℃. For example, the preset temperature gradient ΔT can be obtained based on the preset current ambient temperature T2 being -30℃ and the assembly ambient temperature T1 being 25℃ (i.e., ΔT = T1 - T2).

[0056] Since the compensation element 220 adjusts the position of the fourth lens group 214 in the optical axis direction, the adjustment coefficient K can be determined to be 1. That is, the preset compensation amount ΔX = 0.022mm.

[0057] In step 420, since ΔT > 0, ΔD > 0, and ΔX > 0, then B > A. Further, the material of the first lens barrel 215 to the fourth lens barrel 218 in the lens body can be aluminum alloy A6061. The coefficient of linear expansion of this material (i.e., the first coefficient of linear expansion A) is 2.36 × 10⁻⁶. -5 / ℃. Constrained by the original structure of the lens body, the dimension L of the compensation element 220 in the optical axis direction is 4.2mm. Furthermore, according to B=(|ΔX| / L+(A×ΔT)) / ΔT, the linear expansion coefficient (i.e., the second linear expansion coefficient B) of the material of the compensation element 220 can be determined to be 1.3×10⁻⁶. -4 / ℃, and then by selecting a compensation element 220 made of a suitable material and setting the compensation element 220 in the lens body, the optical lens manufacturing is completed.

[0058] The above description is merely a preferred embodiment of this application and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of the invention involved in this application is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the inventive concept. For example, technical solutions formed by substituting the above-described features with (but not limited to) technical features with similar functions disclosed in this application.

Claims

1. An optical lens for temperature drift compensation, comprising: The lens body has a first linear expansion coefficient A; A compensation element is located in the lens body and has a second linear expansion coefficient B; An elastic element is provided for driving the compensation element to adjust the movement distance of at least a portion of the lens body in the optical axis direction; Wherein, the preset temperature gradient ΔT, the preset back focal offset ΔD of the lens body under the preset temperature gradient ΔT, the preset compensation amount ΔX of the compensation element under the preset temperature gradient ΔT, the first linear expansion coefficient A, and the second linear expansion coefficient B satisfy the following rules: When ΔT>0 If ΔD>0 and ΔX<0, then B <A; If ΔD>0 and ΔX>0, then B>A; If ΔD < 0 and ΔX < 0, then B > A; If ΔD < 0, ΔX > 0, then B <A; When ΔT < 0 If ΔD>0 and ΔX<0, then B>A; If ΔD>0 and ΔX>0, then B <A; If ΔD < 0 and ΔX < 0, then B > A; as well as If ΔD < 0, ΔX > 0, then B <A; The elastic element includes a wave spring sheet, and is in a pre-compressed state at the initial assembly temperature; The dimension L of the compensation element in the optical axis direction satisfies: L=|ΔX| / (|(BA)|×ΔT); The compensation coefficient K of the compensation element is related to its position on the lens body, and the compensation coefficient K satisfies: △X=△D×K.

2. The optical lens according to claim 1, wherein, The lens body includes at least one lens, and the elastic element is used to drive the compensation element to adjust the position of at least one lens in the optical axis direction.

3. A method for manufacturing an optical lens for temperature drift compensation, comprising: Based on the preset back focus offset ΔD and the position of the compensation element on the lens body, the compensation coefficient K and the preset compensation amount ΔX of the compensation element are determined, where ΔX = ΔD × K; and Based on the preset temperature gradient ΔT, the preset back focal offset ΔD, the preset compensation amount ΔX, and the first linear expansion coefficient A of the lens body, the second linear expansion coefficient B of the compensation element is determined according to the following rules: When ΔT>0 If ΔD>0 and ΔX<0, then B <A; If ΔD>0 and ΔX>0, then B>A; If ΔD < 0 and ΔX < 0, then B > A; If ΔD < 0, ΔX > 0, then B <A; When ΔT < 0 If ΔD>0 and ΔX<0, then B>A; If ΔD>0 and ΔX>0, then B <A; If ΔD < 0 and ΔX < 0, then B > A; and If ΔD < 0, ΔX > 0, then B <A; The dimension L of the compensation element in the optical axis direction is determined according to L=|ΔX| / (|(BA)|×ΔT); or the second linear expansion coefficient B=(|ΔX| / L+(A×ΔT)) / ΔT is determined according to the dimension L of the compensation element in the optical axis direction. An elastic element is provided in the lens body, wherein the elastic element is used to drive the compensation element to adjust at least a portion of the movement distance of the lens body in the optical axis direction, and the elastic element includes a wave spring and is in a pre-compressed state at the initial assembly temperature.

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