Nokia explains ClearBlack Display (CBD) technology in detail
As Nokia states, ClearBlack display, uses a sequence of polarising layers to eliminate reflections. The image below can explain it a bit better.
Nokia goes on to expain the process as below:
- It hits the linear polariser, this vertically polarises the light. (Polarising means – roughly – aligning the wave vibration in a particular direction)
- Then it hits the circular polariser retardation layer. This converts the light again, making it right-circularly polarised.
- Then it hits the screen and bounces off it, switching the rotation of the light to leftist.
- It goes back through the retardation layer. When this happens, the light becomes horizontally polarised.
- Finally, it hits the linear polariser, since the light is horizontally polarised at this point it can be blocked entirely by this optical solution.