LG Rollable Display Coming to Reality – Interviews with World’s First 18-inch Flexible Display Developers.
Transparent displays and rollable displays are coming into our daily lives, just like science fiction movies and novels have. LG Display recently unveiled the world’s first flexible display and transparent OLED display. LG Display’s newsroom reveals exclusive interviews with the developers of the flexible OLED display and the transparent OLED display. LG Display met with the LG Display OLED Team 3, Chief Research Engineer Won Seo Park and Chief Research Engineer Min Gu Cho.
World’s First 18-inch Flexible OLED Display – Interview with Won Seo Park and Min Gu Cho, Chief Research Engineers of OLED Team 3 at LG Display.
What’s the biggest advantage of the new 18-inch flexible OLED?
Chief Research Engineer Won Seo Park: With our current products, it was possible to bend the screen to a certain extent even with thickness and material limitations. Due to technical limitations, we set our final target to 100R only and did not expect to create a display that could be rolled up completely. We were able to achieve greater curvature radius results than what we had initially expected. The curvature radius of the 18-inch flexible OLED is the technical aspect that most distinguishes it from the previous product. I think that we could bend up to 30R with our current technology. This technology was more than just coming up with a prototype. We worked hard to develop mass production technology, and we were able to implement it for the new 18-inch flexible OLED display. It is advantageous that we can mass-produce flexible OLED displays with our current technology.
Is this the world’s first 18-inch Flexible OLED Display?
Chief Research Engineer Min Gu Cho: The released curved displays are 70-inches or greater in size. Curved displays use a thin glass substrate to create a curve instead of a flexible substrate. The 18-inch flexible OLED is the world’s first technology to use PI (Polyimide) film not only to increase flexibility but also to reduce thickness.
Chief Research Engineer Won Seo Park: One of the most important factors for rolling up a display is the thickness of the panel. One of our current development goals is to minimize that thickness because it can also affect the difference in the curvature radius. When developing the flexible OLED, we came across the issue of scratches on the surface. During the manufacturing process, scratches are created when the panel bumps into something or simply when people handle the panel. As I mentioned earlier, I am focusing on minimizing the thickness of the display and creating a hard protective film. We encountered additional problems when we were separating the glass and plastic substrates, and we are constantly trying to solve these issues.
What was the hardest part of developing the flexible OLED display?
Chief Research Engineer Won Seo Park: The hardest part of developing a flexible 18-inch OLED display was resolving the malfunctioning transistors on the glass and on the PI. Transistors worked just fine on the glass. However, on the PI, the transistors started malfunctioning. The changes in the substrate to resolve this issue also led us to redesign the manufacturing process, as well.
Chief Research Engineer Min Gu Cho:During the manufacturing process, we have to coat the PI on the glass and separate the glass from the completed display. The separation process was not easy. The panel would start malfunctioning when the display was separated from the glass. We are optimizing the manufacturing process by evaluating different manufacturing technologies.