When you look at a display device – your phone, your TV, your smartwatch, the screen in your car – what do you see?  You see the image. A bright, vivid image on surfaces of all shapes and sizes. Flat, curved, flexible, thinner than ever before.

When you stop and think about what goes into displaying one of these amazing images, you might recognize most are protected by a glass cover. You might even be familiar with display types like LCD or OLED. Yet for many, the recognition stops there. You may see the image on the surface, but rarely think about what creates that image, how it achieves life-like, vibrant color, and the journey it makes to reach our eyes.

If we look deeper, beyond the surface and the cover glass of our devices, we would find one or more layers of ultra-thin, technical glass make such images possible. Each layer with a different purpose, all working together to deliver the beautiful displays we use each and every day. Combined, these layers form what we at Corning call the “glass stack.”

It’s worth looking at the individual layers of the glass stack, since each layer is the result of breakthroughs in glass science, optical physics, and state of the art manufacturing. At the top of the stack, we have the protective cover glass of a mobile device that most consumers have heard of – Corning Gorilla Glass. This cover glass protects and maintains the appearance of the display, and also supports the use of front-facing cameras and various sensors. Often, the rear side of such devices is covered with a similar protective glass, which also allows for wireless charging.

A layer deeper, beneath the surface of the glass cover, are the substrates that serve very specific functions depending on the type of display being created.

Though each layer of the glass stack is formed with the same fusion manufacturing process, the compositions of the glass are different – allowing for different properties and benefits. LCD and OLED displays, whether on mobile devices with glass cover and back or otherwise, utilize different super-thin layers of glass specific to their applications:

Certain OLED displays can also be used to create very flexible and even foldable displays. Glass substrates play a very different, but equally important, role as a carrier substrate for flexible OLED displays.  In the process, the carrier glass provides a stable platform for building the display on a very thin layer of plastic bonded to the glass. On its own, this plastic is not sufficiently stable to endure the high-temperature manufacturing process required to build these panels. The carrier glass also has special optical properties to allow separation of the flexible panel from the carrier using a laser at the completion of the panel making process. For these reasons, Corning uses a display-quality glass substrate optimized for the use as a carrier glass to make flexible OLEDs. Carrier glass can be considered part of the glass stack as well, even though it is removed once the panel is complete.

Now when you look at your phone, your TV, your smartwatch, the screen in your car – what do you see? Do you see more than just the image? Can you imagine the layers of the “glass stack” inside?

As display manufacturers continue to push the boundaries of what’s possible, Corning continues to use its unparalleled knowledge of optical physics and materials science to make larger, higher-resolution, thinner, and even flexible displays.

From the glass you use and touch every day, to the glass below the surface you may never see or think about, it all starts with Corning’s deep expertise and continuous innovation in materials science.