Image quality is an important performance factor of IT devices such as TVs and smartphones, and ‘polarizers’ are materials essential for configuring high-definition displays.
Natural light, which are visible lights for humans, vibrate in all directions and spread out everywhere. Polarizers transform natural light that incident as it vibrates in various directions into a light that vibrates to just one direction for transmission. Without polarizers, the screen would be foggy. That is why polarizers are also called ‘digital shutters.’
LCD (Liquid Crystal Display) is a transmissive display that uses liquid crystals between two polarizers to shift the direction or adjust the intensity of light. Meanwhile, OLED (Organic Light-Emitting Diode) is a self-illuminating display that lights up by sending electric signals to the actual OLED cell.
And since it emits lights, one may assume that OLED does not require polarizers, but it is in fact necessary to procure outdoor visibility. Generally, OLED polarizers are used to block external light reflection and offer high visibility for smartphone or laptop screens that are frequently used outdoors.
OLED has no limitations related to viewing angle, allowing the original image to be visible even at an oblique viewpoint, and thus making it possible to use flexible plastics instead of hard glass board. In the future, we just might be able to see OLED laptops that can be rolled and placed in a bag and then unrolled during use.