How does a screen protector protect your device?

(Dan Tri) - A recent survey by Android Authority with more than 5,000 participants showed that 64% of respondents use screen protectors.

Although there is much advice that screen protectors are no longer really necessary, many people still use this accessory to protect their phones (Nicoletaionescu/Getty Images).

A screen protector is a thin layer of plastic or glass placed on the glass surface of the phone screen. The product needs to have the right size and design for each model to ensure the necessary coverage.

The sticker mainly helps limit scratches on the screen surface and can reduce the level of damage when a collision occurs. If the sticker is scratched or cracked, users can remove it and replace it with a new one at a significantly lower cost than repairing or replacing the phone screen.

High-quality glass stickers often have a multi-layer structure, in which each layer takes on a different function.

The top coating helps reduce oil and fingerprints, while the high-hardness glass layer increases scratch resistance. Some products also have adhesive on the underside, which helps hold the glass pieces in place if the patch cracks or breaks.

With plastic stickers, PET (polyethylene terephthalate) has relatively good scratch resistance but limited impact resistance. Meanwhile, TPU (thermoplastic polyurethane) has better flexibility and impact resistance than PET, but its scratch resistance is often not as good as glass.

Why does the touch screen still work when the protective film is applied?

If the sticker is made from high-quality materials and installed properly, this accessory usually does not significantly affect the performance of the capacitive touch screen (photo: Amax Photo/Getty Images).

One of the concerns when using a screen protector is that this accessory can affect touch sensitivity. In theory, the thicker the layer of material placed between the finger and the screen, the greater the potential to affect the touch experience.

Most smartphones today use capacitive touch screens. This technology uses transparent electrodes to detect changes in the electric field when the finger comes into contact with the screen surface. Thanks to that, the device can determine the touch position with high accuracy and support multiple touch operations at the same time.

If the sticker is of good quality, has the right thickness and is installed properly, the effect on touch is usually very small. Conversely, dirt or air bubbles caught between the film and the screen may cause touch operation to be less stable.

Even when installed correctly, some stickers with multi-layer structure and large thickness can still slightly change the feel when handling. Glass stickers are often thicker than plastic versions, while thin products tend to have less impact on the touch experience.

To limit the risk of affecting the touch, users should choose a sticker that is compatible with each phone model, has the appropriate thickness and does not obscure the sensor areas on the screen. For devices that use fingerprint sensors under the screen, choosing a sticker that is confirmed to be compatible by the manufacturer is also especially important.