Optical lens and optical device

Abstract

The embodiment of the invention provides an optical lens and optical equipment. The optical lens includes: a lens barrel having an accommodating space extending along an optical axis; the lens group comprises at least one plastic lens, and the plastic lens is accommodated in the accommodating space; the space ring is arranged between the lens barrel and the plastic lens, the space ring is configured to be capable of being switched between a first state and a second state, and the elastic modulus of at least partial area of the space ring in the second state is lower than the elastic modulus of the same area in the first state; in the first state, the space ring provides rigid support for the lens group; and in the second state, the at least partial area of the space ring deforms, so that the mechanical stress applied to the plastic lens is released and the deformation of the plastic lens is inhibited.

Description

Technical Field

[0001] This application relates to the field of optical display technology, and more specifically, to an optical lens and an optical device. Background Technology

[0002] As head-mounted display devices continue to evolve towards lighter and more compact designs, the choice of materials and structure for optical lenses, as one of their core components, is crucial. Plastic lenses, with their significant advantages such as light weight, ease of mass production, and low cost, have gained widespread application in the field of optical lenses.

[0003] However, plastic lenses are typically made of polymer materials, and the properties of this material mean they face numerous problems in complex usage environments. Specifically, when a plastic lens is subjected to the clamping force of the lens barrel for extended periods, while simultaneously being affected by temperature changes and environmental factors such as humidity and ultraviolet radiation, its internal molecular chains are prone to slippage and recombination. This change at the molecular level triggers irreversible creep deformation that accumulates over time. Once a plastic lens exhibits creep deformation, it will have a series of serious negative impacts on its optical performance. For example, the lens's radius of curvature, center thickness, and surface accuracy will gradually drift, leading to a decline in optical performance. This manifests as a shift in focal length, blurred imaging, and increased distortion, severely affecting the image quality and user experience of head-mounted display devices.

[0004] In view of the above, there is an urgent need to provide a new type of optical lens structure that can actively reduce the stress on the plastic lens when creep occurs, effectively suppress surface drift, thereby ensuring the performance stability of the optical lens and improving the overall quality of the head-mounted display device. Summary of the Invention

[0005] The purpose of this application is to provide an optical lens and optical device to solve the technical defects of plastic lenses in the prior art that are prone to deformation.

[0006] According to a first aspect of this application, an optical lens is provided. The optical lens includes: The lens barrel has a receiving space extending along the optical axis; A lens assembly comprising at least one plastic lens, the plastic lens being housed within the accommodating space; A spacer is disposed between the lens barrel and the plastic lens, and the spacer is configured to switch between a first state and a second state, wherein the elastic modulus of at least a portion of the spacer in the second state is lower than that of the same portion in the first state. In the first state, the spacer provides rigid support for the lens assembly; In the second state, at least a portion of the spacer deforms to release the mechanical stress applied to the plastic lens and suppress the deformation of the plastic lens.

[0007] Optionally, the at least a portion of the spacer ring is configured as follows: In the first state, its elastic modulus is on the same order of magnitude as that of the plastic lens; and in the second state, its elastic modulus is reduced to 1 / 5 to 1 / 4 of that in the first state.

[0008] Optionally, the spacer is integrally formed from a single material and is sleeved around the outer periphery of the plastic lens; In the first state, at least a portion of the spacer ring maintains hard contact with both the plastic lens and the lens barrel. In the second state, at least a portion of the spacer undergoes elastic deformation, thereby transitioning to elastic contact with the plastic lens and the lens barrel.

[0009] Optionally, the single material is a plasticized polycarbonate material.

[0010] Optionally, the elastic modulus of the plasticized polycarbonate material in the second state is reduced to 1 / 5 to 1 / 4 compared to its elastic modulus in the first state.

[0011] Optionally, the inner and outer circumferential surfaces of the spacer are both flat annular surfaces to provide uniform hard contact in the first state and uniform elastic release in the second state.

[0012] Optionally, the spacer ring is provided with alternating concave portions and convex portions in its circumferential direction; The concave portion protrudes towards the optical axis and abuts against the outer peripheral surface of the plastic lens, while the convex portion protrudes away from the optical axis and abuts against the inner wall of the lens barrel, so as to form a hard contact in the first state and achieve stress release through the elastic deformation of the concave portion and the convex portion in the second state.

[0013] Optionally, the spacer is a composite consisting of a plastic shell and a phase change material encapsulated within the plastic shell; In the first state, the plastic outer shell makes hard contact with the plastic lens and the lens barrel respectively; In the second state, the phase change material undergoes a physical phase change, thereby converting the spacer into an elastic contact with the plastic lens and the lens barrel.

[0014] Optionally, the melting point of the phase change material is lower than the ambient temperature when the optical lens is in the second state, so as to trigger the phase change material to change from solid to liquid at the ambient temperature.

[0015] Optionally, the phase change material is selected from single-component or composite materials that have a reversible solid-liquid phase change in the range of 20°C to 80°C and whose melting point is within the working temperature range of the optical lens.

[0016] According to a second aspect of this application, an optical device is provided. The optical device includes an optical lens as described in the first aspect.

[0017] One technical advantage of this application is: The technical solution provided in this application embodiment optimizes the design of the spacer structure, balancing positioning accuracy and stress release. In the first state, the spacer provides rigid support for the lens group, ensuring accurate positioning of the lens group during initial installation and use, meeting the high imaging accuracy requirements of optical lenses. When stress release is needed, the spacer can flexibly switch to the second state, releasing stress through its own deformation. This structural design effectively solves the problems of stress accumulation and deformation in plastic lenses while ensuring the initial positioning accuracy of the optical lens, achieving a combination of structural design and functional requirements, and improving the performance of the optical lens.

[0018] Other features and advantages of this specification will become clear from the following detailed description of exemplary embodiments with reference to the accompanying drawings. Attached Figure Description

[0019] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments of this specification and, together with their description, serve to explain the principles of this specification.

[0020] Figure 1 The diagram shows the structure of the optical lens provided in an embodiment of this application. Figure 1 .

[0021] Figure 2 The diagram shows the spacer structure provided in an embodiment of this application. Figure 1 .

[0022] Figure 3 As shown Figure 2 Assembly diagram of the septum and plastic lens.

[0023] Figure 4 The diagram shows the spacer structure provided in an embodiment of this application. Figure 2 .

[0024] Figure 5 As shown Figure 4 Assembly diagram of the septum and plastic lens.

[0025] Figure 6 The diagram shows the spacer structure provided in an embodiment of this application. Figure 3 .

[0026] Figure 7 As shown Figure 6 Assembly diagram of the septum and plastic lens.

[0027] Figure 8 The diagram shows the structure of the optical lens provided in an embodiment of this application. Figure 2 .

[0028] Explanation of reference numerals in the attached figures: 1. Lens tube; 2. Plastic lens; 3. Spacer ring; 31. Concave portion; 32. Protruding portion; 33. Plastic outer shell; 34. Phase change material; 4. First lens; 5. Second lens; 6. Third lens. Detailed Implementation

[0029] Various exemplary embodiments of the present application will now be described in detail with reference to the accompanying drawings. It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the present application.

[0030] The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the scope of this application and its application or use.

[0031] Technologies and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, such technologies and equipment should be considered part of the specification.

[0032] In all the examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values.

[0033] It should be noted that similar labels and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be discussed further in subsequent figures.

[0034] The technical solution of this application will be further described below with reference to the embodiments and accompanying drawings.

[0035] This application provides an optical lens. (Refer to...) Figure 1 , Figure 8 , Figure 2 , Figure 4 and Figure 6 The optical lens includes: The lens barrel 1 has an accommodating space extending along the optical axis; A lens assembly comprising at least one plastic lens 2, wherein the plastic lens 2 is housed within the accommodating space; A spacer 3 is disposed between the lens barrel 1 and the plastic lens 2, and the spacer 3 is configured to switch between a first state and a second state, wherein the elastic modulus of at least a portion of the spacer 3 in the second state is lower than the elastic modulus of the same portion in the first state. In the first state, the spacer ring 3 provides rigid support for the lens group; In the second state, at least a portion of the spacer 3 deforms to release the mechanical stress applied to the plastic lens 2 and suppress the deformation of the plastic lens 2.

[0036] In this embodiment of the application, the optical lens mainly consists of a lens barrel 1, a lens group and a spacer 3.

[0037] The lens barrel 1, as the basic structural component of the optical lens, has an internal accommodating space extending along the optical axis. This accommodating space provides a stable mounting and fixing area for the lens group. This ensures that the individual lenses in the lens group are arranged in an orderly and precise manner, strictly adhering to pre-set design requirements. When light passes through the lens group, this orderly arrangement ensures that the light propagates along a precise optical path, thereby achieving focused light and clear imaging, providing the foundation for the optical lens to achieve high-quality imaging. Regarding material selection, lens barrel 1 offers several feasible options. For example, plastic can be used, offering significant advantages such as light weight, low cost, and ease of molding and processing. For design requirements where the weight and cost of optical lenses are critical, a plastic lens barrel 1 can effectively reduce overall costs and equipment weight, enhancing the product's market competitiveness. Alternatively, metal can be used for lens barrel 1, possessing high strength and excellent thermal stability. In applications requiring high-strength structural support and adaptability to harsh environments, a metal lens barrel 1 can provide more reliable structural protection for the optical lens, ensuring stable operation even in complex environments.

[0038] The lens assembly includes at least one plastic lens 2, which is housed within the receiving space of the lens barrel 1. The plastic lens 2 has advantages such as light weight, ease of mass production, and low cost; however, it also has the problem of creep deformation under long-term exposure to environmental factors such as clamping force from the lens barrel 1, temperature cycling, humidity, and ultraviolet radiation, leading to a decline in optical performance. (Refer to...) Figure 1The lens group also includes a first lens 4, a second lens 5 and a third lens 6, wherein the first lens 4, the second lens 5 and the third lens 6 can all be made of glass, and the spacer 3 provided in this embodiment may not be provided between the outer periphery of these three glass lenses and the lens barrel 1.

[0039] To effectively address the optical performance degradation caused by creep deformation of the plastic lens 2, this application incorporates a spacer 3 between the lens barrel 1 and the plastic lens 2. This spacer 3 possesses a unique characteristic: it can flexibly switch between a first state and a second state. When the spacer 3 is in the second state, the elastic modulus of at least a portion of its area is significantly reduced compared to the same area in the first state.

[0040] In its first state, spacer 3 possesses a high elastic modulus. Specifically, under normal temperature conditions, the elastic modulus of spacer 3 is similar to that of the plastic lens 2, reaching values ​​of 1000 MPa or even over 2000 MPa. In this state, spacer 3 fully utilizes its rigid support function, constructing a stable and reliable support structure for the lens assembly. This support structure ensures that the lens assembly maintains precise positioning accuracy and good stability during initial installation and subsequent continuous use. Thanks to this characteristic, the optical lens achieves its expected optical performance under normal operating conditions, presenting users with clear and accurate imaging results.

[0041] When the optical lens is under specific environmental conditions, such as a temperature rise during reliability testing of the lens barrel 1, the plastic lens 2 may experience stress accumulation and deformation due to complex factors such as creep. In this situation, the spacer 3 can quickly and promptly transition to the second state. In the second state, the elastic modulus of the spacer 3 decreases to 500 MPa or even lower. Simultaneously, at least a portion of the spacer 3 deforms, encompassing both elastic and physical phase deformation. Through this deformation, the spacer 3 effectively releases the mechanical stress applied to the plastic lens 2, thereby strongly suppressing further deformation of the plastic lens 2 and preventing optical performance degradation caused by deformation of the plastic lens 2. This ensures that the optical lens maintains stable and reliable optical performance under various complex and changing external environmental conditions.

[0042] The following detailed description uses a specific embodiment: In reliability tests conducted on lenses, when subjected to a high-temperature test environment of 60°C to 100°C (preferably 80°C), the elastic modulus of the spacer 3 decreases to below 500 MPa. At this point, the elastic modulus of the spacer 3 is much smaller than that of the plastic lens 2 (the elastic modulus of the lens is approximately 2000 MPa). Under the mutual force between the plastic lens 2 and the spacer 3, due to the lower elastic modulus of the spacer 3, it will preferentially deform and produce a large degree of permanent creep deformation; while the plastic lens 2 only undergoes a small degree of creep deformation, effectively reducing the degree of permanent deformation of the plastic lens 2.

[0043] In this embodiment, by providing a spacer 3 that can switch between a first state and a second state, when the plastic lens 2 faces the risk of creep deformation due to environmental factors, the spacer 3 can promptly switch to the second state. Through deformation of a portion of its own area, the spacer 3 releases the mechanical stress applied to the plastic lens 2, fundamentally suppressing further deformation of the plastic lens 2. This feature effectively avoids optical performance degradation problems such as focal length shift, image blur, or increased distortion caused by drift in the radius of curvature, center thickness, and surface accuracy of the plastic lens 2. It ensures that the optical lens maintains stable and reliable optical performance under different environmental conditions and throughout its service life, providing users with clear and accurate imaging results.

[0044] Because the spacer ring 3 can automatically adjust its state according to the actual situation to cope with the stress changes of the plastic lens 2, the optical lens has a stronger ability to adapt to various complex environmental conditions (such as temperature changes), effectively protects the plastic lens 2, reduces performance degradation caused by environmental factors, thereby improving the overall reliability and service life of the optical lens, and reducing maintenance costs and usage risks. Furthermore, the optimized design of spacer 3 balances positioning accuracy and stress relief. In its first state, spacer 3 provides rigid support for the lens group, ensuring precise positioning during initial installation and use, meeting the high imaging accuracy requirements of optical lenses. When stress relief is needed, spacer 3 can flexibly switch to its second state, releasing stress through its own deformation. This structural design effectively solves the problems of stress accumulation and deformation in the plastic lens 2 while ensuring the initial positioning accuracy of the optical lens, achieving a combination of structural design and functional requirements, and improving the performance of the optical lens.

[0045] The optical lens provided in this application effectively solves the performance degradation problem caused by creep in plastic lenses 2, significantly improving the overall performance and quality of the optical lens. Compared with traditional optical lenses, it has higher stability, reliability, and adaptability, and can be used in a wider range of environmental conditions and application scenarios, such as head-mounted displays, photographic equipment, and optical instruments. This not only enhances the product's competitiveness in the market but also provides new ideas and directions for the technological development and application expansion of optical lenses.

[0046] According to the embodiments of this application, refer to Figure 2 , Figure 4 and Figure 6 The at least part of the region of the spacer ring 3 is configured as follows: In the first state, its elastic modulus is on the same order of magnitude as that of the plastic lens 2; and in the second state, its elastic modulus is reduced to 1 / 5 to 1 / 4 of that in the first state.

[0047] In this embodiment, the elastic modulus of the spacer 3 is defined in the first and second states. The elastic modulus is a measure of a material's ability to resist elastic deformation. The larger the elastic modulus, the more difficult it is for the material to undergo elastic deformation under stress, meaning the material is less prone to elastic deformation and has better stiffness; conversely, the smaller the elastic modulus, the easier it is for the material to undergo elastic deformation and has poorer stiffness.

[0048] In this specific embodiment, at least a portion of the spacer 3 possesses elastic modulus characteristics under two different states. In the first state, the elastic modulus of this portion is on the same order of magnitude as that of the plastic lens 2. This means that under normal operating conditions (such as normal temperature and other conventional environments), this portion of the spacer 3 has similar rigidity and hardness to the plastic lens 2, providing stable and reliable support for the plastic lens 2 and the entire lens assembly. This ensures the positioning accuracy and arrangement stability of each lens in the lens assembly, enabling the optical lens to accurately achieve light focusing and imaging functions according to design requirements.

[0049] For example, in the first state, the elastic modulus of the spacer 3 is in the range of 1000MPa to 3000MPa. Preferably, the elastic modulus of the spacer 3 is in the range of about 2000MPa, which is comparable to the elastic modulus of the plastic lens 2.

[0050] When the optical lens is under specific environmental conditions, such as increased temperature, which may cause stress accumulation and deformation tendencies in the plastic lens 2 due to creep, at least a portion of the spacer 3 will transition to a second state. In the second state, the elastic modulus of this portion will significantly decrease, to within 1 / 5 to 1 / 4 of that in the first state. This significant decrease in elastic modulus makes the spacer 3 more susceptible to deformation under stress, whether elastic or physical phase deformation. Through this deformation, the spacer 3 can actively absorb and release the mechanical stress applied to the plastic lens 2, effectively alleviating stress concentration in the plastic lens 2 and thus strongly suppressing further deformation of the plastic lens 2, avoiding the optical performance degradation caused by deformation of the plastic lens 2.

[0051] For example, in the second state, the elastic modulus of the spacer 3 ranges from 400 MPa to 600 MPa, which is much lower than the elastic modulus of the plastic lens 2.

[0052] According to a specific embodiment of this application, refer to Figures 2-5 The spacer ring 3 is integrally formed from a single material and is sleeved around the outer periphery of the plastic lens 2; In the first state, at least a portion of the spacer ring 3 maintains hard contact with the plastic lens 2 and the lens barrel 1, respectively; In the second state, at least a portion of the spacer ring 3 undergoes elastic deformation, thereby transitioning to elastic contact with the plastic lens 2 and the lens barrel 1.

[0053] In this embodiment, the spacer ring 3 is made of a single material using an integral molding process. This manufacturing method ensures the integrity and consistency of the overall structure of the spacer ring 3, reducing problems such as stress concentration and structural instability that may occur due to the connection or splicing of different materials. The spacer ring 3 is sleeved around the outer periphery of the plastic lens 2. This sleeved structure design allows the spacer ring 3 to fully surround and support the plastic lens 2, providing all-round protection and stability for the plastic lens 2.

[0054] In short, in this embodiment, the spacer 3 has the following characteristics: the spacer 3 is integrally formed from a single material and the spacer 3 can switch between a first state and a second state, wherein the elastic modulus of at least a portion of the spacer 3 in the second state is lower than the elastic modulus of the same portion in the first state.

[0055] In the first state, at least a portion of the spacer 3 maintains hard contact with the plastic lens 2 and the lens barrel 1, respectively. Hard contact means that there is no obvious elastic buffer between the spacer 3 and the plastic lens 2 and the lens barrel 1. The spacer 3 provides stable support for the plastic lens 2 with its own rigidity, ensuring that the plastic lens 2 can maintain accurate positioning and stable alignment during the initial installation stage and under normal use conditions, so that the optical lens can accurately achieve the optical performance as designed.

[0056] When the optical lens is subjected to specific environmental conditions that cause the plastic lens 2 to accumulate stress and deform due to creep or other factors, the spacer 3 enters a second state. At this time, at least a portion of the spacer 3 undergoes elastic deformation (reducing the elastic modulus of the spacer 3), thus transitioning to elastic contact with the plastic lens 2 and the lens barrel 1. This elastic contact allows the spacer 3 to absorb and release stress through its own elastic deformation when subjected to stress, preventing stress from being directly transmitted to the plastic lens 2. This effectively suppresses further deformation of the plastic lens 2 and avoids the optical performance degradation caused by deformation of the plastic lens 2.

[0057] According to an embodiment of this application, the single material is a plasticized polycarbonate material.

[0058] In this embodiment, the spacer 3 is made of plasticized polycarbonate (PC) material, i.e., plasticized PC material. Plasticized PC material is made by adding plasticizers to ordinary PC material. By weakening the secondary valence bonds between resin molecules, it increases the mobility between resin molecules and reduces the crystallinity of resin molecules, thereby significantly enhancing the flexibility of the material.

[0059] This plasticized PC material possesses unique temperature-modulus characteristics. At room temperature, its modulus of elasticity is approximately 2400 MPa, at which point the material exhibits high rigidity and hardness, providing stable support for the plastic lens 2 in the optical lens. When the temperature increases, for example, by 80°C, its modulus of elasticity decreases significantly, dropping below 500 MPa, further enhancing the material's flexibility.

[0060] In optical lens applications, under specific environmental conditions, such as temperature changes, the plastic lens 2 may experience stress accumulation and deformation due to creep and other factors. At this time, the spacer 3, made of plasticized PC material, will undergo elastic deformation due to its reduced elastic modulus and increased flexibility at high temperatures. The spacer 3 absorbs and disperses the stress applied to the plastic lens 2 through its own elastic deformation, effectively suppressing further deformation of the plastic lens 2. This avoids optical performance degradation caused by deformation of the plastic lens 2, such as focus shift and increased aberrations, ensuring that the optical lens maintains stable and reliable optical performance under various environmental conditions.

[0061] It should be noted that adding plasticizers to ordinary polycarbonate (PC) materials is a routine technical operation for those skilled in the art, and will not be elaborated upon in this application. The amount of plasticizer added is determined by the following specific conditions: in the first state, the elastic modulus of the spacer 3 made from the plasticized PC material with the added plasticizer is similar to that of the plastic lens 2 in the optical lens; while in the second state, the elastic modulus of the spacer 3, also made from the plasticized PC material, is reduced to a level that effectively reduces the creep of the plastic lens 2.

[0062] In this specific embodiment, the elastic modulus of the plasticized PC material in the second state is reduced to 1 / 5 to 1 / 4 compared to its elastic modulus in the first state.

[0063] In this embodiment, in the first state, the elastic modulus of the plasticized PC material is comparable to that of the plastic lens 2, which can provide a stable and matching support for the plastic lens 2, ensuring the structural stability of the optical lens during initial installation and normal use, so that light can propagate accurately according to the design path and guarantee the basic optical performance.

[0064] When entering the second state, the elastic modulus decreases significantly to 1 / 5 to 1 / 4, at which point the plasticized PC material exhibits excellent flexibility and elasticity. When the plastic lens 2 experiences creep stress due to temperature changes, the spacer 3 can effectively absorb and disperse this stress through its elastic deformation capability, which is provided by its significantly reduced elastic modulus. This greatly suppresses further deformation of the plastic lens 2, avoiding optical performance degradation problems such as focus shift and increased aberrations caused by the deformation of the plastic lens 2. It significantly improves the performance stability and reliability of the optical lens under different environmental conditions, extends the service life of the optical lens, reduces maintenance costs, and provides a foundation for the optical lens in complex and ever-changing practical application scenarios.

[0065] In this further embodiment, the glass transition temperature of the plasticized PC material is lower than that of the plastic lens 2, so that the spacer 3 can be switched from the first state to the second state after being triggered by a preset temperature.

[0066] In this embodiment, the glass transition temperatures of the plasticized PC material and the plastic lens 2 are set. The glass transition temperature is the critical temperature point at which a material transitions from a glassy state to a highly elastic state, and different materials have different glass transition temperatures. In this embodiment, the glass transition temperature of the plasticized PC material is set to be lower than that of the plastic lens 2. This setting ensures that when the preset temperature is triggered, the plasticized PC material will undergo a state transition before the plastic lens 2. When the ambient temperature reaches the preset temperature (which is higher than the glass transition temperature of the plasticized PC material but lower than that of the plastic lens 2), the plasticized PC material transitions from a glassy state to a highly elastic state, thereby realizing the transition of the spacer 3 from the first state to the second state. In the first state, the spacer 3 provides stable support for the plastic lens 2 due to its mechanical properties adapted to the plastic lens 2; while in the second state, the spacer 3, having become highly elastic, possesses better flexibility and elastic deformation capability to cope with potential creep and other problems that may occur in the plastic lens 2.

[0067] In one specific embodiment, refer to Figure 2 and Figure 3 The inner and outer circumferential surfaces of the spacer 3 are both flat ring surfaces to provide uniform hard contact in the first state and uniform elastic release in the second state.

[0068] In this embodiment, in the first state, the spacer 3 needs to provide stable and reliable support for the plastic lens 2 in the optical lens. The inner and outer circumferential surfaces of the flat (without protrusions or depressions) ring can form uniform hard contact with adjacent components (such as the plastic lens 2 and the lens barrel 1). This uniform hard contact means that the contact pressure distribution between the spacer 3 and the adjacent components is uniform, and there is no local stress concentration. This ensures that in the first state, the spacer 3 can firmly fix the plastic lens 2, preventing unnecessary displacement due to external interference or its own gravity, and ensuring the initial optical performance and structural stability of the optical lens.

[0069] When entering the second state, due to changes in the properties of the plasticized PC material (such as changes in elastic modulus caused by factors like temperature, as mentioned earlier), the spacer 3 needs to possess a certain elastic deformation capacity to cope with potential creep and other problems in the plastic lens 2. At this time, the flat inner and outer circumferential surface design of the ring allows the spacer 3 to achieve uniform elastic release during elastic deformation. In other words, the elastic deformation of the spacer 3 is consistent throughout the entire circumference, preventing localized excessive or insufficient deformation. This uniform elastic release can more effectively absorb and disperse the stress generated by creep in the plastic lens 2, thereby more precisely suppressing further deformation of the plastic lens 2 and ensuring the optical performance of the lens under different conditions.

[0070] In another specific embodiment, refer to Figure 4 and Figure 5 The spacer ring 3 is provided with an inner concave portion 31 and an outer convex portion 32 alternately in its circumferential direction; The concave portion 31 protrudes toward the optical axis and abuts against the outer peripheral surface of the plastic lens 2, while the convex portion 32 protrudes away from the optical axis and abuts against the inner wall of the lens barrel 1, so as to form a hard contact in the first state and achieve stress release through the elastic deformation of the concave portion 31 and the convex portion 32 in the second state.

[0071] In this embodiment, the spacer 3 has alternating concave portions 31 and convex portions 32 in the circumferential direction. This structural design changes the contact method between the spacer 3 and the plastic lens 2 and the lens barrel 1. Specifically, the concave portions 31 bulge towards the optical axis and can closely abut against the outer peripheral surface of the plastic lens 2; while the convex portions 32 bulge away from the optical axis and abut against the inner wall of the lens barrel 1.

[0072] In the first state, this design creates multiple hard contacts, meaning that the spacer 3 interacts with the plastic lens 2 and the lens barrel 1 through multiple discrete contact surfaces or points, providing a stable support structure for the optical lens. When entering the second state, due to changes in material properties (such as changes in elastic modulus caused by temperature) and the inherent structural design of the spacer 3, the concave portion 31 and the convex portion 32 of the spacer 3 are more prone to elastic deformation, thereby releasing stress. Compared to a flat toroidal spacer 3 structure, in this embodiment, the spacer 3 only contacts the lens and lens barrel 1 at certain locations, and these contact points are separated. This design makes the spacer 3 more prone to deformation, enabling it to more flexibly cope with stress changes generated by the plastic lens 2 under different operating conditions.

[0073] According to a specific embodiment of this application, refer to Figure 6 and Figure 7 The spacer ring 3 is a composite consisting of a plastic shell 33 and a phase change material 34 encapsulated within the plastic shell 33; In the first state, the plastic outer shell 33 forms hard contact with the plastic lens 2 and the lens barrel 1 respectively; In the second state, the phase change material 34 undergoes a physical phase change, thereby converting the spacer ring 3 into an elastic contact with the plastic lens 2 and the lens barrel 1.

[0074] In this embodiment, the spacer 3 is designed as a composite structure, consisting of a plastic shell 33 and a phase change material 34 encapsulated therein.

[0075] In the first state, the plastic housing 33 and its internal phase change material 34, due to their relatively stable physical properties, ensure that the spacer 3 makes hard contact with the plastic lens 2 and the lens barrel 1, respectively. This hard contact provides a stable and reliable initial support for the optical lens. This stable support ensures that the optical lens can accurately achieve its designed optical performance in the initial state. For example, the focus can be accurately placed at the predetermined position, and aberrations are effectively controlled, thus presenting users with clear, sharp, and high-quality optical images, meeting the stringent requirements of the optical lens for initial optical performance in various application scenarios.

[0076] In the first state, the phase change material 34 is a solid material, and the spacer 3 structure formed by the plastic shell 33 and the phase change material 34 is relatively rigid, which meets the assembly requirements of the lens.

[0077] When entering the second state, due to the influence of external conditions (such as temperature changes), the phase change material 34 encapsulated within the plastic shell 33 undergoes a physical phase change, for example, changing from a solid to a liquid or semi-solid state. This significantly alters the overall physical properties of the spacer 3, transforming it from a hard contact state in the first state to an elastic contact state with the plastic lens 2 and lens barrel 1. Alternatively, for example, the phase change material 34 changes from a solid to a liquid or semi-solid state, while the plastic shell 33 itself softens. These two changes work together to significantly alter the overall physical properties of the spacer 3, transforming it from a hard contact state in the first state to an elastic contact state with the plastic lens 2 and lens barrel 1. For example, the plastic shell can be made of low-density polyethylene (LDPE), polystyrene (PS), polypropylene (PP) thin-walled products, polyvinyl chloride (PVC), transparent TPE materials, etc., which can soften at high temperatures.

[0078] When entering the second state, this elastic contact can better adapt to the deformation and stress changes that may occur in the plastic lens 2 under different working conditions, so as to deal with the creep and other problems that may occur in the plastic lens 2.

[0079] For example, the phase change of the phase change material 34 can absorb or release a large amount of heat, acting as a thermal buffer during temperature changes and reducing damage to the plastic lens 2 caused by thermal stress. Furthermore, the softening of the plastic shell 33, when the plastic shell can be softened, gives it better flexibility and elastic deformation capability. This allows the spacer to undergo corresponding elastic deformation with the deformation of the plastic lens 2, uniformly dispersing and absorbing the stress generated by the plastic lens 2. This effectively suppresses further deformation of the plastic lens 2, avoiding optical performance degradation problems such as focus shift and increased aberrations caused by deformation, ensuring that the optical lens maintains excellent optical performance under different operating conditions, and improving the reliability and stability of the optical lens.

[0080] According to an embodiment of this application, the melting point of the phase change material 34 is lower than the ambient temperature when the optical lens is in the second state, so as to trigger the phase change material 34 to change from solid to liquid at the ambient temperature.

[0081] In this embodiment, the phase change material 34 encapsulated within the plastic housing 33 of the spacer ring 3 structure used in the optical lens is specifically configured with parameters set such that its melting point is lower than the ambient temperature when the optical lens is in its second state. When the optical lens is in its second state, the ambient temperature reaches or exceeds the melting point of the phase change material 34. At this time, the phase change material 34 will change from a solid to a liquid state. This phase transition process, in conjunction with the softening of the plastic housing 33, will change the overall physical properties of the spacer ring 3, transforming it from a hard contact state with the plastic lens 2 and lens barrel 1 to an elastic contact state, in order to meet the special requirements of the optical lens in its second state.

[0082] Specifically, in the second state, after the phase change material 34 transforms into a liquid state, it exhibits better fluidity and flexibility. When the plastic lens 2 deforms and generates stress due to factors such as temperature changes, the liquid phase change material 34 can act as a "buffer," uniformly absorbing and dispersing these stresses. Compared to the solid phase change material 34, the liquid phase change material 34 can better fill the tiny gaps between the spacer 3 and the plastic lens 2 and the lens barrel 1, forming a tighter and more uniform contact, thereby more effectively transferring and dispersing stress throughout the entire spacer 3 structure. This stress absorption and dispersion capability reduces the local stress concentration experienced by the plastic lens 2, lowers the risk of permanent deformation of the plastic lens 2, and helps maintain the long-term stable optical performance of the optical lens.

[0083] According to embodiments of this application, the phase change material 34 is selected from single-component or composite substances that have a reversible solid-liquid phase change in the temperature range of 20°C to 80°C and whose melting point is within the operating temperature range of the optical lens. For example, the phase change material 34 can be paraffin wax, fatty acids, polyethylene glycol (PEG), etc.

[0084] In this embodiment, paraffin wax is preferably selected as the phase change material 34. Paraffin wax, as the phase change material 34, has many significant advantages. First, at room temperature, paraffin wax is chemically stable and does not easily react with other surrounding substances. This ensures its stable performance during long-term use and under various complex and changing environmental conditions, guaranteeing the reliable operation of the optical lens in different scenarios. Second, during the cooling process, when the temperature reaches the solidification point of paraffin wax, it solidifies rapidly without overcooling, thus ensuring the stability and repeatability of the phase change process. This is crucial for maintaining the performance consistency of the spacer ring 3 structure. Third, paraffin wax has a wide phase change temperature range. By mixing paraffin waxes with different carbon chain lengths, its phase change temperature can be flexibly adjusted between 20 and 80°C, thereby meeting the precise temperature control requirements of various application scenarios.

[0085] In practical applications, paraffin wax is encapsulated within a specific shell material (plastic shell) to form an encapsulation structure. At room temperature, paraffin wax is a solid material, and the spacer ring 3 structure is relatively rigid, possessing good rigidity and stability. This meets the stringent requirements for support and positioning during lens assembly, ensuring accurate installation of the plastic lens and maintaining its initial optical performance. However, during temperature-related reliability testing in high-temperature environments, the paraffin wax material transforms into a liquid state, and the shell structure of spacer ring 3 softens accordingly. This change allows spacer ring 3 to undergo elastic deformation under stress, effectively reducing the stress on the plastic lens 2 and lowering the risk of permanent creep deformation.

[0086] Furthermore, the melting point of paraffin material can be altered by adjusting the proportion of paraffin materials with different carbon chain lengths. Based on this characteristic, the phase transition temperature of paraffin can be precisely set according to the temperature requirements of reliability testing. For example, if the maximum temperature for reliability testing is set to 80℃, the phase transition temperature of paraffin can be set to 60℃, ensuring that the melting point of the paraffin material is lower than the reliability testing temperature. In this way, the paraffin transforms into a liquid before the lens temperature reaches the reliability testing temperature, and the spacer ring 3 structure softens accordingly. Compared to plastic lenses, spacer ring 3 is more easily deformed under stress, thus significantly reducing the stress on the plastic lens and further effectively reducing the degree of creep permanent deformation of the lens.

[0087] According to a second aspect of this application, an optical device is provided. The optical device includes the optical lens described above. Specifically, the optical device may include, but is not limited to, augmented reality (AR) devices, virtual reality (VR) devices, or cameras.

[0088] The above embodiments mainly describe the differences between the various embodiments. As long as the different optimization features between the various embodiments are not contradictory, they can be combined to form a better embodiment. For the sake of brevity, they will not be elaborated here.

[0089] While specific embodiments of this application have been described in detail by way of examples, those skilled in the art should understand that the above examples are for illustrative purposes only and are not intended to limit the scope of this application. Those skilled in the art should understand that modifications can be made to the above embodiments without departing from the scope and spirit of this application. The scope of this application is defined by the appended claims.

Claims

1. An optical lens, characterized in that, include: The lens tube (1) has an accommodating space extending along the optical axis; A lens assembly comprising at least one plastic lens (2) housed within the accommodating space; A spacer (3) is disposed between the lens barrel (1) and the plastic lens (2), and the spacer (3) is configured to switch between a first state and a second state, wherein the elastic modulus of at least a portion of the spacer (3) in the second state is lower than the elastic modulus of the same portion in the first state. In the first state, the spacer (3) provides rigid support for the lens group; In the second state, at least a portion of the spacer (3) deforms to release the mechanical stress applied to the plastic lens (2) and suppress the deformation of the plastic lens (2).

2. The optical lens according to claim 1, characterized in that, The at least part of the region of the spacer (3) is configured as follows: In the first state, its elastic modulus is on the same order of magnitude as that of the plastic lens (2); and in the second state, its elastic modulus is reduced to 1 / 5 to 1 / 4 of that in the first state.

3. The optical lens according to claim 1, characterized in that, The spacer ring (3) is integrally formed from a single material and is sleeved around the outer periphery of the plastic lens (2); In the first state, at least a portion of the spacer ring (3) maintains hard contact with the plastic lens (2) and the lens barrel (1), respectively; In the second state, at least a portion of the spacer (3) undergoes elastic deformation, thereby transitioning to elastic contact with the plastic lens (2) and the lens barrel (1).

4. The optical lens according to claim 3, characterized in that, The single material is a plasticized polycarbonate material.

5. The optical lens according to claim 4, characterized in that, The elastic modulus of the plasticized polycarbonate material in the second state is reduced to 1 / 5 to 1 / 4 compared to its elastic modulus in the first state.

6. The optical lens according to any one of claims 3-5, characterized in that, The inner and outer circumferential surfaces of the spacer (3) are both flat ring surfaces to provide uniform hard contact in the first state and uniform elastic release in the second state.

7. The optical lens according to any one of claims 3-5, characterized in that, The spacer (3) has an alternating inner concave portion (31) and an outer convex portion (32) in its circumferential direction. The concave portion (31) protrudes toward the optical axis and abuts against the outer peripheral surface of the plastic lens (2), while the convex portion (32) protrudes away from the optical axis and abuts against the inner wall of the lens barrel (1) to form a hard contact in the first state and to achieve stress release through the elastic deformation of the concave portion (31) and the convex portion (32) in the second state.

8. The optical lens according to claim 1, characterized in that, The spacer (3) is a composite consisting of a plastic shell (33) and a phase change material (34) encapsulated within the plastic shell (33); In the first state, the plastic shell (33) forms hard contact with the plastic lens (2) and the lens barrel (1) respectively; In the second state, the phase change material (34) undergoes a physical phase change, thereby causing the spacer (3) to be converted into an elastic contact with the plastic lens (2) and the lens barrel (1).

9. The optical lens according to claim 8, characterized in that, The melting point of the phase change material (34) is lower than the ambient temperature when the optical lens is in the second state, so as to trigger the phase change material (34) to change from solid to liquid at the ambient temperature.

10. The optical lens according to claim 8 or 9, characterized in that, The phase change material (34) is selected from single-component or composite materials that have a reversible solid-liquid phase change in the range of 20°C to 80°C and whose melting point is in the working temperature range of the optical lens.

11. An optical device, characterized in that, The optical device includes an optical lens as described in any one of claims 1-10.

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