To ensure that optical lenses for automotive surveillance meet waterproof and dustproof requirements during outdoor use, the sealing process must be tailored to the optical lens' structural characteristics, outdoor environmental impacts, and long-term stability. This involves a comprehensive protection system encompassing sealing structure design, material selection, assembly processes, and post-production verification. This system ensures that core components, such as the optical lens assembly and photosensitive element, are protected from rain and dust, while also maintaining the lens's light transmission and image quality.
First, the sealing process for optical lenses prioritizes fundamental protection from a structural design perspective. An optical lens for automotive surveillance typically consists of a lens barrel, multiple lens elements, a focusing mechanism, and a housing. The joints between these components are crucial for waterproofing and dustproofing, and are also the most susceptible to gaps. For the interface between the lens barrel and lens, a "contact seal" design is employed. A specific sealing groove is reserved on the mating surface between the lens and the barrel, where a matching sealing element is embedded. This ensures a tight fit between the lens and the barrel after installation, preventing dust or water from seeping through the lens edges. As for the connection between the lens barrel and the housing, due to the constant vibrations generated by a vehicle in motion, static bonding alone can easily create gaps. Therefore, a "stepped sealing structure" is designed. This multi-stage bonding surface increases the sealing path length. Furthermore, a sealing layer is applied to each bonding surface, creating multiple layers of protection. Even if a small gap appears in one section, the subsequent sealing layers can still prevent impurities from entering and directly affecting the interior of the optical lens.
Secondly, the selection of sealing materials is crucial for ensuring waterproof and dustproof performance, requiring consideration of weather resistance, sealing properties, and compatibility with optical lenses. In outdoor environments, optical lenses are subject to the rigors of high and low temperatures, exposure to sunlight, rain, and varying humidity. Conventional sealing materials are prone to softening at high temperatures, cracking at low temperatures, or aging failure. Therefore, highly weather-resistant elastic sealing materials are selected. These materials maintain their elasticity over a wide temperature range, preventing degradation of sealing performance due to ambient temperature fluctuations. Furthermore, the selected sealing material must be compatible with the optical lens' lens and barrel materials, preventing corrosion or adhesion, thereby preventing damage to the lens coating or the inner wall of the barrel, and thus affecting the optical lens's light transmittance and image clarity. For example, when sealing the lens and barrel, materials that could chemically react with the lens coating are avoided to ensure a seal without compromising the optical performance of the optical lens.
Furthermore, meticulous assembly processes are crucial for achieving effective sealing, requiring strict control of cleanliness and the accuracy of the sealing element's installation. Dust and impurities on the optical lens' sealing surface can prevent the sealing element from fully contacting the sealing surface, creating tiny gaps. Therefore, assembly must be performed in a clean environment to ensure that the sealing surface and sealing element are free of impurities. During installation, specialized tools are used to ensure the sealing element's flatness, preventing distortion or misalignment. This ensures uniform compression and a stable sealing contact pressure. Excessive pressure can cause the sealing element to deform and fail, while too little pressure can prevent an effective seal. Only by precisely controlling the pressure can the sealing element form a continuous and uniform protective layer on the sealing surface. Furthermore, the sealing process for moving parts of the optical lens, such as the focus and zoom, utilizes a "dynamic sealing" design. This design incorporates a dynamic sealing structure at the interface between the moving and fixed components. This ensures smooth movement while also blocking impurities in real time, preventing seal failure due to component movement.
Finally, after the sealing process is complete, verification testing is conducted in simulated outdoor environments to ensure the optical lens meets actual water and dust resistance requirements. These tests simulate the conditions likely encountered by vehicles outdoors, such as heavy rain, dust, high and low temperatures. The sealing performance of the optical lens is tested under various environmental conditions, observing for water and dust infiltration and verifying whether image quality is affected. If any weaknesses are identified, targeted optimization of the sealing structure, adjustment of materials, or refinement of the assembly process are implemented to ensure that the optical lens consistently maintains a good seal in all types of outdoor environments, ensuring long-term stable operation and providing clear, reliable imaging support for in-vehicle surveillance. Through the design and implementation of this series of sealing processes from structure, materials, assembly to verification, the vehicle monitoring optical lens can effectively resist the intrusion of outdoor rain and dust, meeting the protection needs of outdoor vehicle use.
