The touch screen is almost the majority of a smartphone, as the screen is both a control device for the smartphone and an output device.
At the same time, the screen is not the strongest part of the phone, so using a smartphone over time leads to microscopic scratches on the screen, and if used carelessly, cracks may appear.
Protective films and tempered glass were designed to protect the smartphone screen from damage. In this article, we will consider different screen protectors, their features, advantages, and disadvantages and try to determine the best one.
Types of protective screen accessory
Here are four basic ways to protect your smartphone screen:
Film screen protector
This accessory is a thin film that is glued to the phone screen. The qualitatively glued film will not be visible on your screen. As the protective film is very thin, it does not affect the sensitivity of the touch control. When using protective film, the color, brightness, and viewing angles of the screen are not distorted.
The protective film is preferable for smartphones with a built-in ultrasonic fingerprint scanner, as its thickness does not affect the authentication process.
How effectively does the film protect the screen? The film is effective when the screen comes into contact with non-sharp objects or sand. The film does not protect the phone screen from crushing or impact when it is dropped. The good part is that if the glass breaks, sharp shards of glass will remain under the film, which reduces the chance of injury.
There are also decorative protective films that are glued to the back glass surface of some smartphones. The main purpose of decorative films is to reduce sliding in hand, reduce the formation of scratches, and give a specific appearance due to different textures or patterns. Also on sale are universal films with a layout, which allows you to cut out the protective surface of any size.
Types of Protective Films
There are several types of protective films:
- PET (polyethylene terephthalate)
- TPU (Thermoplastic polyethylene)
Everything we wrote above about protective films refers to PET. These are protective films made of polyurethane – plastic, which should be familiar to you (for example, by plastic bottles). Polyurethane films protect against not very strong screen impacts.
The advantage of PET films is that they’re cheap. The disadvantages are, firstly, weak screen protection; secondly, the film turns yellow over time.
This type of protective film withstands stronger impacts on the screen but not the strongest ones. For example, this film can prevent coins or keys from scratching the screen. This film is a little more expensive than the one before it. The disadvantages are that it has a slightly roughened surface and adds orange highlights to the screen.
In addition, some films contain oleophobic spraying, which reduces the formation of greasy traces on the screen from sweaty fingers. Oleophobic spraying makes it easier to slide your finger on the surface, and the water on the screen drains off without affecting your smartphone. But oleophobic spraying is usually erased from the screen in 1-2 weeks, so it should be periodically applied to the screen again. Sprayers and gels are sold for this.
- Affordable price. For the price of one tempered glass you can often buy 3-5 films.
- Maintains a high response to the screen sensor
- Keeps the screen bright and colorful
- Presence of universal films with a layout under any screen
- A preferred choice for smartphones with an ultrasonic fingerprint scanner
- Oleophobic coating
- Weak protective properties
- Difficult installation process
- Low service life
Tempered glass is characterized by increased strength due to the residual mechanical compression stress generated during hardening.
Most glasses consist of several layers: a silicone base for fastening, tempered glass, a clamp that prevents sharp splinters from flying when the glass breaks, an oleophobic coating. As in the case of the film, the oleophobic coating is erased after a certain time.
Compared to film, the glass is thicker, so it absorbs mechanical energy better when a fall causes impact; most of the destructive energy falls on the protective glass. In the worst case, the glass breaks and needs to be replaced, and some of the unabsorbed mechanical energy is transferred to the smartphone screen, which can damage the smartphone if the impact is severe enough. Therefore, the safety glass does not provide 100% safety.
Tempered glass better protects against unwanted contact with abrasives and sharp objects. The packaging usually indicates the hardness of the glass on the Mohs scale – 9H. In theory, such glass can only scratch the hardest minerals, such as Corundum or Diamond. In reality, most cheap glasses have a hardness of 4-5H.
Tempered glass does not degrade the sensitivity of the touch screen, nor does it affect color reproduction or image clarity. The process of installing the glass on the screen is easier as air is squeezed out under the weight of the glass, and it is easier to get rid of air bubbles. And if you install it unevenly, it’s easy to remove and re-install.
At the same time, tempered glasses cause difficulties for the ultrasound fingerprint scanner. To scan a fingerprint, it is important that the finger fits the screen tightly. A few tens of microns of protective film do not affect the reading process, but hardened glass with a thickness of 0.5 mm or 0.33 mm does not allow authentication. To solve this problem, you can use glass from a certified manufacturer or glass with a finger cut-out, but the latter does not look aesthetically pleasing.
- High protective properties and long service life.
- Easy installation process.
- Does not affect the touch screen response
- Smooth surface
- Does not affect the brightness and color rendering of the screen
- Oleophobic coating
- Most glasses are not suitable for smartphones with ultrasonic fingerprint scanners
- Each smartphone requires individual glass
Hydrogel screen protector
It resembles a PET film. And in general, the hydrogel film is similar to PET film. In the case of hydrogel film, the presence of polymer in the composition allows you to eliminate bubbles with air, which were formed by incorrect installation. Small bubbles leave after a couple of hours, large after a couple of days. The hydrogel film is self-repairing – shallow damage is delayed after a couple of hours or days.
The hydrogel screen protector cannot withstand severe impacts and other types of mechanical impacts; it has a low mechanical energy absorption value, similar to that of a protective film. Therefore, you should not rely on the safety of the glass under the film if the phone hits hard or falls on the asphalt.
- Low cost, comparable to conventional films
- Restore shallow scratches
- Easy installation. Bubbles with air are absorbed after time
- Touch screen does not lose sensitivity
- Retains original brightness and color reproduction of the screen
- Suitable for smartphones with built-in optical and ultrasonic dactyloscopic scanner
- Oleophobic coating
- Low protective properties
- No universal films with a layout for any screen
Liquid screen protector
Liquid glass is a liquid that, once applied to the smartphone screen, creates a thin protective surface. With liquid glass, it creates a pleasant tactile effect comparable to the original factory glass. At the same time, the protective properties of liquid glass are worse than conventional a film. In addition, some users who have tried this screen protector complain about difficulties with installation and do not recommend buying liquid glass.
This article describes in detail the types of protective glass and film for your smartphone. The best protection is provided by tempered glass. But tempered glass is not suitable for smartphones with ultrasonic fingerprint sensor (but you can try a glass with a cutout under your finger). Of the protective films, the best option is hydrogel film, as it has self-repair for shallow damage and no problems with air bubbles.