Screen Guards: Comparing PET Film, TPU and Tempered Glass
Screen guards today come in three varieties: PET film, TPU (polyurethane), and the undisputed leader - tempered glass. Let’s see how the three screen protectors work and what they offer.
PET (polyethylene terephthalate) is a type of plastic available in several variations. The polyester film for guarding the screen has a scratch resistant matte coating on one side and a silicone adhesive on the other. However, there is no impact protection and even the scratch-resistance is limited to fingernails, coins and keys. Although they come cheap, the plastic gets easily discolored from the sun rays and oil build-up from the fingers. The feel is also not as good as the glass.
TPU (thermoplastic polyurethane) is chemically-enhanced plastic with properties including scratch resistance, oil and grease resistance, increased toughness and elasticity. Slight elasticity allows it to absorb non-extreme impacts, such as most drops and lighter scratches. It will usually leave just a small dent in the plastic, which would slowly regain the shape.
Tempered glass (TG) screen protectors, A state-of-the-art TG protector has multiple layers. Shock absorbent silicon is on the bottom layer followed by PET film. An adhesive attaches these layers with the next two - the tempered glass and oleophobic coating. All of this won’t exceed .4mm.
Tempered glass scores over PET film and TPU on variables such as toughness, feel, look and installation. Having said that, not all tempered glass screen protectors are the same. Cheaper protectors have problems in installation, oleophobic coating and quality of glass. Substandard glass may have trouble with multi-touch input. There may also be fingerprints on the glass screen. These troubles may not be the deal breaker, but they can be frustrating.
When buying screen protector, go for the ones that assure you of the quality. They may be slightly expensive, but they may not be found lacking in performance.