How fingerprint scanners work

There are several ways to unlock your phone, from pin numbers to passwords, patterns, and fingerprint scanners, which one is the best option to go with? You may be surprised to find out that the best option for you may indeed be the fingerprint scanner.

If you’ve been keeping up with fingerprint scanning for any length of time, you already know it gets a bad rap the majority of the time. From the stories of people’s phones being mysteriously hacked to the overall faultiness of getting your finger in the same spot all of the time, it’s no wonder that so many people are wary of choosing to go with it over, or alongside with, the other available security options.

That’s why today, we’re bringing you an overview on three of the popular fingerprint scanners, how they work, the advantages and disadvantages, and how they might be a great option after all.

What is a fingerprint scanner and how does it work?

The name “fingerprint scanner” essentially speaks for itself. It’s a scanner that takes in your unique fingerprint, and in the case of phones, will unlock your smartphone completely or open your second layer of chosen security. While in the past the idea of fingerprint scanners seemed to be ominous and only used in movies that included spies and secret agents, fingerprint scanning is making headway and becoming the norm in our digital age.

To go even further, just as we have seen all of our technology evolve (including smartphones), fingerprint scanning has evolved, and is continuing to evolve, as well. There’s a variety of different kinds of fingerprint scanning software, as it had to start somewhere, but to keep it simple, we’ll talk about the three major developments of fingerprint scanners.

One of the original, but popular fingerprint scanning software was called “Optical.” Optical fingerprint scanning was and is extremely straightforward, because it simply does a quick scan of your finger, and you’re done. The only problem with this method is that it’s a little too straightforward, in that because it essentially just takes a quick snapshot of your fingertip, it’s not very secure. There is no real depth to it, and unfortunately that’s where a lot of the security issues with fingerprint scanning come in. All someone would need to get past your fingerprint scanner is a photo.

The second major fingerprint scanner we want to talk about is called “Capacitive.” With capacitive fingerprint scanning, you can’t just use a photo of someone’s finger to hack through their system, because your skin contact matters here. If you look closely at, say, your index finger (or any finger for that matter), you’ll notice the extremely small, barely noticeable print. Because those ridges and circles are unique to you, and each of those has to actually be touching the surface you’re scanning through, this is a much more secure fingerprint scanning software, and actually it’s what is included with most smartphones. However, that being said, while capacitive fingerprint scanning is more reliable security-wise than optical fingerprint scanning, it’s not the most up-to-date or the best fingerprint scanning software.

No, in fact, capacitive fingerprint scanning also has it’s flaws. For it to work correctly, your skin must be extremely clean, and even a papercut or something of the like could prevent you from getting through to your phone. While those aren’t terrible downsides by any means, they’re definitely not always convenient.

This brings us to the third major fingerprint scanner we’re going to talk about, and it’s Qualcomm’s “Ultrasonic” fingerprint scanner. While it can do everything that capacitive fingerprint scanning can do, it goes the extra mile in the right places, rather than just advancing the roadblocks to make fingerprint scanning an unnecessary hassle.

With Qualcomm’s ultrasonic fingerprint scanner, you shouldn’t have any problems unlocking your phone if you recently applied lotion, ate a messy lunch, or worked on a vehicle or your most recent renovation project. Because of the ultrasonic fingerprint scanner advanced technology, it can scan even deeper into your fingerprint, ignoring anything that isn’t the heat or contact of your skin, such as lotion or other residue. Rather than doing a mere surface scan of what your fingerprint looks like, and even of what your fingerprint feels like, the ultrasonic fingerprint scanner even goes as far as your individual pores. This makes any forgery and anything of the like nearly, if not completely, impossible.

What phones can utilize fingerprint scanning for unlocking?

In the newer phones, fingerprint scanning has become the norm. More often than not, when you get a new phone, fingerprint scanning will be one of your options for security, along with your typical pin, password, or pattern. And although you might have heard horror stories in the past about people hacking into devices because fingerprint scanning technology is so poor on the security side of things, we encourage you to think again.

What are the benefits of fingerprint scan unlock vs. other security options?

There are several benefits to selecting a fingerprint scan to unlock your device rather than choosing other security options. For starters, especially if you’ve been able to get your hands on a device that utilizes Qualcomm’s ultrasonic fingerprint scanning (or may be referred to as Sense ID), it’s one of the most secure options for unlocking your phone. You simply cannot get  much deeper than this scan, which should set your mind at ease.

The second benefit is that it could save you a lot of time. Simply swiping your pattern or typing in your code might not seem like it takes a whole lot, but if you’re constantly finding yourself moving from one meeting to the next, fingerprint scanning really is the most efficient option. And if you’re one to unlock your phone and then use voice commands, a fingerprint scan to unlock will minimize your distractions so you can watch where you’re going, multitask, and overall just pay better attention whatever it is you’re working on.


Whether you end up deciding to go with fingerprint scanning to unlock your phone or not, we hope you found this article informative and interesting. If nothing else, we hope it inspired you to do more research on recent fingerprint scanning technology. Just like all other technology, it has come a long way over the years, and we can’t wait to see where it will be 20, 10, and even five years from now.

About the Author: Brad Ward

Brad is a tech enthusiast, writing and tinkering with all things technology since 2011. He currently bounces between the LG G3 and his beloved Moto X! His interests include reading, entrepreneurship, the gym, and of course, queso.

  • russell conrad lewis

    Your credibility died a horrible death when you refer to PIN as a “pin numbers.”