1. Unpacking the layers of science that help make smartphone screens brighter
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  • Unpacking the layers of science that help make smartphone screens brighter

    By Kelly Hall, 3M Storyteller

    A woman lounges while looking at her smartphone.

    You can’t see it or feel it, but tiny technologies are having a powerful impact in your smartphone.

    The tech is so small, you have to shrink down to smaller than a human hair to understand exactly how they work.

    • Even though Lina Liu doesn’t think about it, this technology is giving power to something she thinks about and uses all the time – something she can’t imagine living without – and something she always has at her fingertips: her smartphone.

      Lina lives in China, home to a smartphone empire. Around half of the Chinese population is projected to use a smartphone by 2020. By that time, there are expected to be more than 257 million smartphone users in the United States, another location where the smartphone industry is on the rise. Smartphone users across the globe are catching up too. By 2020, there will be more than six billion smartphone users worldwide.

    • Graphic illustration of the layers in a smartphone, showing films, adhesives and more

      That’s because with the touch of a screen, we are using our smartphones for everything. For instance, Lina says she uses her smartphone for every aspect of her life in China.

      “I use it to check emails and my calendar, read news, listen to music, book hotel reservations and watch videos for entertainment,” she says. “My smartphone makes my life more convenient.”

      But in a world with customers constantly wanting the latest and greatest technologies and smartphone makers racing to meet their needs, what is it about today’s smartphones that will grab your attention?

      Smartphone developers look to create more than one “it” factor. With each of us spending more than four hours a day on our phones, it’s no wonder that one of these “it” factors is the quality of your phone’s display.

      And scientists are ahead of the curve. They know that screen brightness is important to you and other aspects of your life, like your photos.

      “In China, people like to take pictures of their food in restaurants, interesting things they see on the street, beautiful sights seen during their traveling – and then post them on social media and share them with their friends,” says Lina.

      That’s why 3M scientists utilize surprising technologies – like films and tapes, to push forward the cutting-edge features helping our phones work the way they do. The result? Brighter cell phone screens, enhanced displays and longer battery lives.

      Looking at the layers

      Let’s dive deeper into the many layers of smartphone displays, starting with 3M’s Advanced Polarizing Film (APF). At only about 27 microns thick – equivalent to about a quarter of the size of a strand of human hair – this reflective film is incredibly thin and slick. But, don’t let its lack of bulk fool you. It is also very powerful. 3M scientists designed the film to recycle polarized light back into the phone, resulting in a brighter display.

      “Without the APF, approximately 50 percent of light would be absorbed – and essentially wasted by the display. However, the APF film can help reuse that light so it can increase the efficiency by 40 to 50 percent for any given phone,” says Tony Wang, who researches display materials at 3M.

      There’s another kind of film you may find working behind the screen to increase brightness in smartphones: high-brightness prism films. Like the APF, they are very thin, but also extremely durable. Working together, both the APF and prism films help improve the display of text, images and colors on your screen.

      The display-brightening technology doesn’t end there.

    • : “My smartphone makes my life more convenient.” - Lina Liu, Smartphone user in China

      Brightness enhanced through reflector technology

      Light entering the phone is reflected and bounced back toward the display with minimal light loss, thanks to 3M’s Enhanced Specular Reflector (ESR), based on multi-layer optical film technology.

      Even though you’ve never noticed all of this is happening in your phone, this science is influencing many of your everyday life experiences – texting, reading, watching videos, taking photos and shopping online are just to name a few.

      A battery for your on-the-go lifestyle 

      And since the brightness-enhancing technologies help phones consume less power, they can also help smartphones have improved battery efficiency, allowing phones to be able to withstand a much smaller battery – one that can last just as long as a larger smartphone battery.

      Vance Hua, part of the team working with these technologies at 3M China, says scientists are working on batteries that can last anywhere between two to three days. A smaller battery also allows smartphones to be thinner, and therefore easier to carry at home, in the car, at work, in the gym, while traveling – essentially everywhere. Scientists are learning about the lifestyles of smartphone users to bring us solutions we need.

      “In China, your phone is a declaration of your lifestyle,” says Lina.

      These lifestyles will continue to be redefined for all generations as smartphone manufacturers continue working with 3M scientists to keep enhancing their smartphones – creating solutions to both common and unique issues we face as smartphone users.

      “Our goal is for smartphone manufacturers to come to us with the most challenging problems in order to enable the designs that they’re planning to launch in the market,” says Stacy Davis, Director of Business Development for the Electronics and Energy group at 3M. “This allows us to not only provide solutions that we’ve already commercialized in the market, but to also look toward future solutions.”

    Take a closer look at the paper-thin stack of 3M science that goes into many smartphones.