Dec 12 AT 5:00 PM Brooks Barnard 162 Comments

Why I don’t use screen protectors: An engineer’s perspective


Phones are expensive; you probably spent a couple hundred dollars on your phone. Plus, you typically sign a two-year contract when you buy a phone. So, it’s worth it to keep your phone in good condition–not only for potential resale value, but because you’re going to have to look at it and use it for a long time.

Obviously, there are a couple of things people do to take care of their phones, like use screen protectors and cases. I’ll leave cases for another post and discussion, but these are things you’re probably super familiar with and may even be using on your phone right now. They’re cheap and offer an extra layer of protection between your phone and the brutal world that is trying to destroy it.

That said, I don’t use screen protectors.

Why you ask? Well, for several reasons. First, I suck at putting them on. I can’t think of an experience installing a screen protector where I didn’t end up with some hideous air bubbles. Second, I don’t love the way screen protectors feel. Depending on how much money you spend on your screen protector, they can absolutely alter the experience you have while interacting with your device. They can be slightly grippier, or softer. For better or for worse, the experience can change. Third, I’ve seen a lot of screen protectors that discolor over time. I’m not sure if they collect the oils from your fingers or if it’s some sort of degradation of the plastic, but your viewing experience might not be as clear as it could be. And lastly, I don’t feel like I need it. Phone manufacturers use materials on your device’s display that are engineered specifically to not scratch under most conditions. I’ll do my best to explain.

Material hardness

Hardness is a word used by scientists or engineers to classify materials. Maybe you’ve discussed hardness in other situations, but I don’t think I’ve ever used the word hardness in this context outside of class or some engineering conversation. Regardless, one way that the hardness of materials are classified is by actually using different materials to scratch other materials. In general, a harder material cannot be scratched by a softer material. For example, diamonds are at the top of the hardness scale. I don’t suggest you try this, but the only thing you’re going to find out there that may scratch a diamond is probably another diamond. However, the gold wedding bands that are held by the diamonds scratch pretty easily. Gold is a pretty soft metal, so there are many materials out there that can scratch it. Therefore, to keep rings pretty, they need to be replated every once in a while. Once, being the nerd I am, I told my wife that her diamond could scratch my proclaimed unscratchable tungsten carbide wedding band. So she tried it out, and now my wedding band is scratched.

Anyway. Back to phones. Typically phones these days have glass on their displays, and most have an enhanced glass called Gorilla Glass by Corning Glass. I’ve briefly tried to do a little research and figure out how hard Gorilla glass is compared to other materialsmohs en. According to Corning’s spec sheet for Gorilla Glass 3, the glass had a hardness between 534 – 649 kgf/mm^2. (Interestingly, this is softer than the original Gorilla Glass). If we check out the hardness scale to the right, we see that this value falls under the category of scratchable by a steel file (which is typically a hardened steel). This means that anything softer than a steel file like household knives, keys, or coins would likely not scratch your display. In addition to the hardness of Gorilla Glass, Corning uses special coatings on the glass surface to reduce its ability to collect fingerprints and also improve abrasion (scratch) resistance.

So what does this all mean? There are limited number of materials that we come into contact with on a daily basis that will actually scratch your phone’s display. With some easy-to-learn strategy, you can avoid both using a screen protector and accumulating scratches on your display.

Strategy to avoid scratches

Here’s what I do: I have a designated pocket where a put my phone that nothing else ever goes into besides the occasional plastic pen or chapstick. This could be a pants pocket or a purse pocket. It doesn’t really matter. What matters is keeping your phone away from accidental contact with materials that can scratch it like other glass, some rare metals and what I think is one of the biggest display scratching culprits: sand.

We all know it’s a thing. Pocket sand can wreck a phone. I know purses get it too. So you obviously need to think this through and make a plan that works for you. I personally am rarely around sand or dirt and never put anything in my designated phone pocket except for my phone, so I haven’t run into the pocket sand issue. But sand, especially beach sand, is the hard material left over from thousands of years of waves crashing and wearing it down. It’s hard stuff and will easily scratch all parts of your phone. When I go to the beach, I put my phone in a plastic sandwich bag and don’t take it out until I’m sure the coast is clear.

Additionally, if you use the same pocket for your phone every time, you won’t have to frantically search for it when someone calls. You may even misplace it less. This is a life hack for using your phone that’s worked for me and kept my phones pretty. It may work for you, too.

The naked option isn’t for everyone

Obviously, using your phone without a screen protector isn’t for everyone. Maybe you’re a lifeguard on a beach or your life circumstances mean you’re around a lot of sand or materials that may scratch your display. Or you don’t mind the annoyances that come with screen protector use. I have nothing against you. My intention in writing this post is to improve awareness. I feel like there are a lot of people out there who feel like they NEED a screen protector to keep their display scratch free, and that’s not the case. Companies have spent a great deal of time and money on research to make your phone’s glass tougher and more scratch resistant. Some simple strategies or routines can help save you a bit of money and hassle with screen protectors and keep your device pretty.

What do you think? Can you brave using your phone without a screen protector? Do you already not use a screen protector? What are your strategies for keeping your display scratch free? Chime in and let us know your thoughts by commenting below!

Brooks is an engineer living in the Bay Area recently dislocated from the Great Northwest. He's an Android enthusiast who decided to start doing something (productive?) with his countless hours surfing the interwebz and addictive ROM flashing and began writing. He has a hot wife, is a father of two, an avid F1 fan, and enjoys watching sports when he can. His current devices include the Nexus 5 and 7 (2103) both running stock roms rooted and modded with Xposed Framework (but this is subject to change). You can follow Brooks on Twitter @Brooks_Barnard.

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