Apple begins development of OLED panel without polarizer 

Similar tech used by Samsung for Fold 3

2022-05-10     Gijong Lee
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Apple has begun the development of an OLED panel that doesn’t use a polarizer, TheElec has learned.

The removable of the polarizer on the panel will allow them to be made thinner, which makes them more optimal for foldable panels, sources said.

Polarizers are used to allow only lights in certain directions to pass through, thereby improving the visibility of the display.

However, its use lessens the brightness, thereby affecting the luminance efficiency of the panel as well. Companies usually increase the power consumption of the panels to offset this but this also leads to less lifespan for the panels.

Removing the polarizer and applying technology with a similar effect resolves these trade-offs.

Samsung Display was the first to supply an OLED panel without a polarizer. It supplied them to parent company Samsung Electronics for the Galaxy Z Fold 3.

Instead of using a polarizer film, Samsung Display printed a color filter on the thin film encapsulation __ abbreviated as CF on TFE __ and added a black pixel define layer.

This allowed the foldable panel to offer clearer colors through the color filter, the sources said.

The black pixel define layer replaces the conventionally used orange pixel define layer made out of photo-sensitive polyimide. Using an orange pixel define layer as before would have reflected the light, affecting the contrast ratio.

A different polyimide material was used for the black pixel define layer.

Samsung Display is calling its CF on TFE technology ECO2, or Eco Square. The company had claimed that this technology can increase light transmittance by 33% and lower power consumption by 25% more than its previous display panels.