In a recent Blog post Nokia has finally revealed the secret behind its ClearBlack display that is available on the Lumia range of devices that recently launched in South Africa for the first time.
ClearBlack basically gives users of the device a clear black display in in the fullest of direct sunlight. The problem with all modern smartphones is that the power consumption that is used to power these screens is substantially more than what it used to be. To start with manufacturers dimmed the screen light to prolong battery life, this led to problems with usability outdoors. The next evolution was to cover the screen with an anti reflective covering for the screen, which works to a point, but no further.
Enter ClearBlack with its polarizing capabilities. The diagram above give a good idea of how it works. However see the below explanation direct from Nokia as to what happens when light hits the screen:
1. It hits the linear polariser, this vertically polarises the light. (Polarising means – roughly – aligning the wave vibration in a particular direction).
2. Then it hits the circular polariser retardation layer. This converts the light again, making it right-circularly polarised.
3. Then it hits the screen and bounces off it, switching the rotation of the light to leftist.
4. It goes back through the retardation layer. When this happens, the light becomes horizontally polarised.
5. Finally, it hits the linear polariser, since the light is horizontally polarised at this point it can be blocked entirely by this optical solution.
Now with Nokia providing diagrams to other OEM's in the marketplace, surely it is only a matter of time till we can expect other devices with similar technologies. This might start the next series of patent wars in months to come as Nokia tries to defend its IP.
