Protective glasses are made for specific models of smartphones, so before choosing, you need to know exactly the name of the device brand and its model – up to a few numbers or letters after the main name. This affects whether the glass will fit, match the speaker cutout and other holes. You can pick up and universal glass, but it does not guarantee 100% protection of the screen surface.
Smartphone screen protectors can be made of various materials, not necessarily glass. They all have different tensile strengths. The choice of screen protection is influenced by such characteristics as thickness, hardness, transparency, oleophobic coating. Let’s consider these issues in more detail.
What types of protection are there?
How to choose a protective glass? Consider the types of glass:
2D glass is flat glass with rounded edges. This glass completely covers the flat surface of the screen of the mobile device.
2.5D glass – glass completely covers the surface of the curved screen of the mobile device. Glass with a colored frame looks more natural and inconspicuous on the smartphone screen.
3D glass – completely repeats the shape of the rounded edges of the device screen, which maximizes the protection of the screen from mechanical damage.
Another type is hybrid glass . It combines a thin protective film with the protective properties of glass. Hybrid glass is more flexible than regular glass, making it more impact resistant. The disadvantage is that it is highly susceptible to scratches.
It is believed that the larger the D number (5D, 9D, 10D), the better the glass. In reality, this is not so – there is no system for evaluating glasses and assigning a certain number to them, this is just a name that each manufacturer comes up with at its discretion.
Typically, the structure of a safety glass consists of five layers:
Silicone base that fixes the glass to the display.
A restraining layer that prevents a broken screen from shattering into shards.
Anti-glare layer that prevents the screen from dimming in bright light.
Protective layer to prevent damage to the display.
Oleophobic coating to prevent grease and fingerprints from sticking to the screen.Glass coating type
Glossy finish is standard. Such glass most accurately conveys the image, retains the brightness of the backlight, almost invisible on a smartphone.
The matte / anti-reflective coating avoids glare, slightly, but still distorts colors, making them appear paler. A convenient option for frequent use of the gadget in the sun or in rooms with very bright lighting.
The privacy / anti-spy coating is a special, darkened type of glass, in which the contents of the display are visible only when viewed from a right angle. If you look at the phone or tablet from the side, you will see only a black screen, but as soon as you turn the gadget to face you, an image will immediately appear. The use of such glass is relevant if you want to hide the contents of the screen from prying eyes. For example, in public transport, only you will see what is displayed on the screen.
How to determine the quality of an oleophobic coating
Test number 1 “Marker and water drops”
If water droplets spread over the glass surface, and the line drawn with a marker is practically not blurred (photo 3), then the oleophobic coating is of poor quality. Photo 4 shows glass with a high-quality oleophobic coating: drops are collected, but it is impossible to draw a line with a marker – the marker ink is collected in dots.
Test number 2 “Special equipment”
With the help of special equipment, a drop of water is applied to the protective glass . The smaller the contact area of the water drop with the glass surface, the larger the angle and the better the oleophobic coating
Glass strength is measured on the Mohs Mineralogical Scale, which indicates the ability of a surface to resist scratches, cracks and chips.
To create the gradation, ten natural minerals were used, which were lined up by Mohs, depending on the damage they inflicted. As a rule, according to the Mohs mineralogical scale, the strength of protective glass ranges from 4H to 6N.
Often, manufacturers are tricky and claim that the strength of the protective glass is 9H. But there is a catch: this indicator is equated to the hardness of the lead of an ordinary pencil for drawing.Glass thickness
The thickness of the protective glass is one of the indicators responsible for the reliability of the device. Its value varies from 0.1 to 1 mm.
Remember that a protective glass that is too thick reduces the sensitivity of the mobile device’s screen sensor.
Thick glass visually enlarges the smartphone, making it uncomfortable and aesthetically unattractive. Therefore, it is better to adhere to the “golden mean” – glass thickness 0.3-0.33 mm.
For 2D / flat glass without a frame, the adhesive is applied to the entire surface of the safety glass.
For 2.5D / flat glasses with a colored frame and 3D, manufacturers use glue only on the safety glass frame or glue on the entire surface of the safety glass.
Glass with glue along the frame has a lower cost and easier installation, but now this method of applying glue is rarely used, since it has a number of disadvantages after gluing, for example, air bubbles may appear, which are difficult to remove after gluing the edges of the glass.
How to choose a protective film for your gadget?
Protective films have the same purpose as glass: to protect the screen of the gadget so that it is not damaged. Of course, the film is not very suitable to protect the gadget from being hit or dropped, but the screen will be protected from scratches.
There are different types of protective films:
antispyware / private
There are films for a specific gadget model, there are universal models and there are films that can be cut out for your gadget right in the CSN store. The device that cuts the film for a specific gadget is called a plotter, and the film is called a plotter.
Plotter film is a hydrogel film that is a moisture-resistant and self-healing non-toxic polymer. Indeed, small scratches on these films are restored some time later. The versatility of the film is also an advantage – the plotter can quickly cut the film for your device. It is quite simple to stick it on. Any user can cope with this, but it is better to entrust this business to professionals.
Basic life hacks: how to choose the perfect screen protector?
Thick tempered glass with 0.5 mm and 9 N characteristics is suitable for those who often drop the phone to the floor. With this protection, the display is unlikely to be damaged if dropped.
Smartphones with glass cases and large screens are often very slippery and heavy. To protect them, it is recommended to choose a cover and glass immediately when buying a gadget.
Phones with small screens are usually compact. They fit easily in the hand and rarely fall. You can do with minimal protection – a hydrogel film.
Children are usually not very careful about their gadgets. Durable glass will help preserve the screen of children’s smartphones.
If you carry your smartphone in a jacket or trouser pocket, where there are no other items, it is enough to protect the screen with a high-quality film. If the phone often lies in the bag next to keys, wallet and other little things, it is better to use glass.
If, after some time after the protection sticker, bubbles appear on the screen, a network of cracks has formed, corners have begun to peel off or the sensitivity of the sensor has worsened, then it is time to change the protection.