The US PTO published a new patent from Apple (filed in 2012) that describes how to use sensors to compensate for ambient lighting (see DisplayMate's related recent article) and lifetime brightness degradation in OLED displays. The patent describes that photo-diodes can be placed inside the OLED array or above and below it.

Putting photo-diodes inside the display will enable them to more accurately measure light levels. So if a part of the screen is dimmer than the rest of the screen (for example because only a part of the display is under direct light) - the photodiode will detect it and then the display brightness in that area can be increased. This is something that cannot be achieved with a single sensor. Those photodiodes can also be used to learn whether certain OLED pixels (or pixel groups) have lowered brightness due to aging. Then the display can compensate and drive these pixels higher.

Update: It turns out that these displays aren't made by RitDisplay at all. Hopefully I'll be able to provide more information soon...

Since CMEL stopped producing AMOLEDs in 2009, it was impossible to get low-volume AMOLED as Samsung and LG will only ship to large-volume applications (mobile phones, cameras, etc). But today Densitron informed us that they started shipping new HVGA (320x480) 3.5" a-Si AMOLEDs panels.

Densitron says that the DLA320480AB035F module features 10,000:1 contrast ratio, near 180-degree viewing angle and a brightness of over 200 Candela. It uses Himax's HX5227-A AMOLED driver and includes a MIPI-DBI 8/16/24 bit MPU parallel interface. For applications where high quality video streaming is required, the 8/16/24 data line parallel video (RGB) interface option is available.

OLED Technologies & Solutions (OTS) released a new corporate presentation video which introduces the company and their new inkjet-printing based OLED processing line, the PCA-48:

The PCA-48 line is a 4.5-Gen (730x920 mm) line that incorporates TFE, Ink-Jet Printing, and high vacuum transportation technologies. OTS uses Merck polymer and Small-Molecule materials and their production line supports all substrates (including a-Si using Ignis' technology). OTS that they can deliver and install a complete production line within 12 months, and a single line will be able to produce 40 million smartphone displays in a year. This is the line that AIV-BEX wants to use in their proposed AMOLED production fab.

Ignis innovation announced a new all-electrical inspection system for AMOLED manufacturing lines called MaxLife Inspection. This system provides information on each individual pixel and detects defects which can be repaired using a laser system. This system will increase yields by 2-5 times according to Ignis.

The MaxLife Inspection system uses a probe card, custom electronics and the MaxLife Viewer software to measure the brightness of every pixel in an OLED display with a 14-bit resolution. The system can be used before OLED deposition on the TFT backplane to find defective pixels and explain why they failed (this can be fixed by laser or new a deposition pass). The system can also be used after the OLED deposition to detect OLED defects (shorted pixels, etc.). It can also detect uniformity problems (such as speckles, "Mura" issues, etc.) after the final assembly of the panel.

Ignis Innovation announced that samples of its 20" 1296x768 (XGA) AMOLED display will be available in August 2013. Ignis will offer these samples to display makers for evaluation of Ignis' MaxLife compensation technology in their own displays (more on this below). They will sell the display for low volume, demanding applications such as medical imaging and scientific imaging.

The 20" AMOLED panels use a-Si backplane and are made by RiTdisplay. The panels are only 1.3mm thick (the complete display module is 3 mm thick). The refresh rate is 240Hz.

Back in June 2012 I reported from SID on Ignis' Max Life technology. Max Life provides external compensation - that deals with OLED burn-in. The idea is to keep track of how much each pixel was used, and so it's possible to calculate the brightness loss in that particular pixel, and then drive this particular pixel correctly - to compensate. Ignis now released a nice video showing a 20" AMOLED panel (their own a-Si prototypes made by RiTDisplay) with a burn-in logo. When Max Life is turned on, the logo disappears:

Ignis explains that while Max Life theoretically makes the "eventual" lifetime (until the display burns out completely) worse, in practice it helps to make the device usable longer. Ignis says that the main problem is non-uniformity in brightness and not actual brightness.

Yesterday I posted about the Galaxy Note 2 subpixl scheme, with the 5.5" 1280x720 HD Super AMOLED display featuring 267 ppi (with three subpixels per pixel). Our readers pointed out that the new scheme used in the Note 2 looks very much like Ingis Innovations' patented HR pixel structure (as part of their AdMo-p technology). This may explain how Samsung managed to get good enough lifetime at such a high PPI without PenTile.

Just as a reminder, here's how the Note 2 pixels are arranged. It's not exaclty the same as in the HR structure as the red and green sub-pixels have the same size. In any case:

As I already said before, Ignis Innovation's SID booth was one of the conference highlights for me. Their technology is very impressive and hopefully will enable cheaper non-LTPS AMOLED production.

In their booth, Ignis were showing 3.5" and 20" AMOLED panels that use the company's a-Si backplane compensation technology. The panels were made by RiTdisplay. Ignis and RiTdisplay have been showing these displays back in 2011. Originally they were supposed to be released towards the end of 2011, but this never happened. During SID Ignis announced that now the plan is to release these by the end of 2012. According to Ignis the 3.5" AMOLED will be cheaper than the LTPS-based competition (i.e. Samsung made panels). You can read more about these panels and RiTdisplay's plans at my RiTdisplay-at-SID-2012 post.

RiTdisplay is a PMOLED producer based in Taiwan that has several production lines making PMOLED panels. A few years ago it was considered the world's largest PMOLED maker, although I now hear that due to financial problems the company shut down some of their PMOLED lines (this isn't confirmed though).

At SID 2012, RiTdisplay showed several PMOLED panels, and some 3.5" AMOLED panels. RiTdisplay is Ignis' production partner for its a-Si compensation technology, which basically enables a-Si to be used as a backplane for AMOLED panels (instead of LTPS or Oxide-TFT). This should enable cheaper AMOLEDs. You can read more about this technology at my Ignis-at-SID post.

Update: Here's the complete list of OLED related posts and notes from SID 2012

So, SID 2012 is now over. Personally it was a very good show, even though I hear from many exhibitors that it was slow compared to past years. There were a lot of companies showing OLED displays, lighting panels and related products, and it seems that OLEDs are starting to become mainstream. I do plan to post in-depth posts with interesting details of my talks with various OLED companies, but in the meantime, here's my own "best of SID" list.