What Is a Waterproofing Membrane?

After the surface of the lens is coated with multiple layers of antireflection film, the lens is particularly prone to stains, and the stains will destroy the antireflection effect of the antireflection film. Under the microscope, we can find that the antireflection film layer has a porous structure, so the oil stain is particularly easy to infiltrate the antireflection film layer.

Waterproof membrane

After the surface of the lens is coated with multiple layers of antireflection film, the lens is particularly prone to stains, and the stains will destroy the antireflection effect of the antireflection film. Under the microscope, we can find that the antireflection film layer has a porous structure, so the oil stain is particularly easy to infiltrate the antireflection film layer. The solution is to coat a layer of anti-reflection and water-resistant top film on the anti-reflection film layer, which is also called a waterproof film. And this film must be very thin so that it does not change the optical properties of the anti-reflection film.

The material of antifouling film is mainly fluoride, there are two processing methods, one is immersion method, the other is vacuum coating, and the most commonly used method is vacuum coating. After the anti-reflection film layer is completed, fluoride can be plated on the reflection film by using an evaporation process. The antifouling film can cover the porous antireflection film layer, and can reduce the contact area of water and oil with the lens, making oil and water droplets difficult to adhere to the lens surface, so it is also called a waterproof film.

For organic lenses, the ideal surface system treatment should be a composite film that includes an anti-wear film, a multilayer anti-reflection film, and a top film antifouling film. Usually the anti-wear film coating is the thickest, about 3-5mm, the thickness of the multilayer anti-reflection film is about 0.3um, and the top antifouling wax coating is the thinnest, about 0.005-0.01mm. Take France's Crizal and composite film as an example. The lens substrate is first plated with an abrasion resistant film with silicone; then IPC technology is used to apply anti-reflection coating with ion bombardment Pre-cleaning before the vacuum cleaning; vacuum cleaning of multiple anti-reflection coatings using high-hardness zirconia (ZrO2) and other materials after cleaning; and finally coating with a waterproof film with a contact angle of 110 WR2 waterproof membrane). The successful development of the diamond crystal composite film technology shows that the surface treatment technology of organic lenses has reached a new level.

The waterproof and dustproof film reduces the contact area of water and dust with the lens to an angle of 110 degrees, and makes it difficult to adhere to the lens surface, so the filter surface will be smoother and more waterproof, anti-fog, and anti-fog. Anti-pollution functions such as dust and anti-fingerprint. It can be widely used on the lens of the camera, the optical products such as the dustproof sheet on the window products of electronic digital products, and the window products such as touch screen. Waterproof and dustproof films are usually used together with anti-reflection coatings on window products, which can also increase the hardness of the lens surface and also prevent scratches. Anti-scratch here is not 100% anti-scratch. Here it refers to the regular micro-scratch, which protects the window. This coating can also be used together with reflective film in automotive mirror products. When the water falls on the surface of the filter, it can slide down like the water on the lotus leaf, so that the optical window can maintain a clear field of vision.

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