According to reports, Apple is negotiating with Korean panel manufacturers to cooperate in developing a screen technology that will completely change the appearance of the iPhone. It plans to introduce a true four-sided full-curved OLED display for the 2028 iPhone and use new transparent electrode technology.The core of this technology is that Apple requires suppliers to replace the traditional opaque OLED cathode layer with a new transparent cathode material based on indium zinc oxide. This material can improve the transparency of the luminescent layer and reduce visual distortion and uneven brightness at the four curved edges of the panel.
In top-emitting OLEDs used in smartphones, light must pass through the cathode layer. The traditional magnesium-silver alloy cathode has limited transparency, resulting in distorted images and reduced brightness in the curved portion of the screen. The light transmittance of IZO transparent electrode is much higher than that of traditional materials, which can reduce edge brightness loss by more than 30%.
However, IZO transparent electrode technology is still in the early stages of research and development, and is limited by special equipment and will be difficult to mass-produce before 2027.
Apple chose to take a two-step approach: first, complete the four-sided micro-curved shape with the 20th Anniversary Edition in 2027, and then equip the 2028 model with IZO transparent electrodes to achieve a technical closed loop of display effects and mass production processes.
Supplier LG Display announced last month that it will invest approximately 1.106 trillion won, which will be used exclusively for the development and final mass production of IZO transparent electrode technology.This process requires the installation of special low-damage TCO sputtering equipment. LG plans to use it for research and development first and then gradually expand the scale.
Samsung Display is also evaluating investment, but the existing OLED production line space is limited, and the installation of TCO sputtering equipment faces physical constraints. The industry generally believes that Samsung may need to build a new dedicated production line to meet Apple's requirements.
Apple is urging both suppliers to speed up progress to catch up with product releases in 2028.
