AMOLED screens have promised to deliver displays which have richer,
deeper colours; better viewing angles; using up to 50 per cent less power and costing
a lot less. However an issue with the TFT backplane has meant that they have
yet to live up to their promise.
A Canadian company, Ignis Innovation, has now announced
however that newly developed technology has meant that it has been able to
produce a AMOLED display with a pixel density of 330ppi using a
conventional RGB matrix whioch should eliminate the uissues with the backplane.
Currently the Retina display on the iPhone 4 and iPhone 4S
is the king in terms of pixel density, coming in at around 330ppi but the new
technology could see AMOLED displays soon challenge it for the crown.
An AMOLED display is comprised of a OLED layer, which emits
light, and a TFT backplane which controls the brightness of the OLEDs by
providing current to them.
Traditionally the problem with AMOLED displays was down to
these polysilicon backplanes which don’t provide uniform current because of
manufacturing non-uniformities – resulting in lines, spots, and cloudy areas
known as “mura”.
However Ignis AdMo-p technology uses a patented TFT pixel
circuit and driving scheme to compensate for the non-uniform backplane. So the
TFT circuits always provide uniform current to the OLEDs, even though the TFTs
themselves aren’t uniform.
It is the AdMo-p technology and its newly-developed 3-TFT
pixel circuit which has allowed Ignis to manufacture AMOLED displays with
a 330ppi pixel density. A brief press release from Ignis claimed that using these
techniques will allow AMOLED displays compete with IPS.
“These techniques can make AMOLED displays with similar
resolution as IPS displays but with much better color quality, higher contrast
ratio, and wider viewing angle.”
Ignis will not manufacture the new displays themselves but will licence the technology to OEMs. It is unclear how liong it will take before we see this technology used on mobile phones or tablets but the sooner the better we say.