Power consumption - Page 23

Google was granted a new patent (filed in July 2013) that describes a technique for saving power on mobile devices with OLED displays. Basically the idea is that the when battery is low, the system can change the display characteristics (lower the resolution, disable animation and use red and black colors only). You can see the basic schema from the chart below, which is actually quite badly written: there's no option for a normal mode, and there's just one check and no loop as there should have been. Oh well...

This patent is only useful and valid for OLED displays. I'm not sure how canceling blur and animation actually conserve power on OLEDs. Showing just red and black colors make sense, and reducing the resolution also makes sense if they mean showing a small image with black around it. In September 2012 Google were granted a patent in which they suggest to reduce the image on a screen when the device is idle - this is basically the same idea which relies on the fact that black pixels on OLED displays do not draw power.

NEC Lighting developed transparent OLED lighting panels that use a transparent ITO film - and they plan to commercialize these panels by 2015. The company unveiled a prototype 20x20 cm panel that features 70% transmittance, 35 lm/W efficacy and 20,000 hours lifetime (not sure if that's LT70 or LT50). This panel was developed in collaboration with Japan's New Energy and Industrial Technology Organization (NEDO).

Last week NEC Lighting announced that they developed the world's most efficient OLED device to day at 156 lm/W.

Since Samsung unveiled their 4.99" Full-HD AMOLED panels at CES 2013, we assumed that the Galaxy S4 will use those panels. Some supply-chain analysts from Korea confirmed this. But then, towards the end of February, SamMobile posted that the S4 will in fact not use an OLED at all, but rather a 4.99" Full-HD SoLux LCD display.

Today the same blog posted a new post saying that they received new information about the S4 - and indeed it will use a new kind of AMOLED display - one with green PHOLEDs (instead of the fluorescent green currently used by Samsung) - which will make it 25% more efficient. This isn't really news - it was expected and we reported this back in early February. But it's good to see this new post by SamMobile anyway.

Verbatim announced their 3rd-Gen Velve color-tunable OLED lighting panels, and the company managed to increase the efficacy to 51.6 lm/W. The brightness is the same as in their 2nd-gen panels (2,000 cd/m²). The panels weigh 193 grams and the active area is 123x123 mm. In fact it seems to be exactly the same as their previous panels.

Verbatim did not reveal when the expect to release those panels and at what price. We don't have any technical details either, but it's likely that these are phosphorescent panels. The OLED is manufactured by Mitsubishui Chemical (Verbatim's parent company) in partnership with Pioneer. Back in June 2012 we posted a hands-on review of the first-gen Verbatim panels, here's a short video from that review:

NEC Lighting announced that they developed a new OLED lighting device that has an efficiency of 156 lm/W - that's the world's most efficient OLED to date. This device was co-developed with Yamagata University's research group led by Junji Kido. You can see Professor Kido's work in the video below (from 2011):

The device is 2x2 mm in size and the brightness is 1,000 cd/m2. NEC said that the emitter materials were developed in the Kido Lab of Yamagata University. Unfortunately NEC did not reveal the structure and technologies used to fabricate this OLED.

Tridonic announced a new 99x99 mm LED module called the LUREON REP, that features high efficiency (50 lm/W) and high light output (100 lm). Other features: 4000K color temperature, CRI > 80 and a low color angle shift. Tridonic says that the high brightness coupled with the high efficiency will allow them to use OLEDs in professional lighting applications. The LUREON REP modules will be available in mid-March.

Philips GL350 is actually brighter at 115 lm (it's larger though at 124x124 mm), but it is far less efficient at 16.7 lm/W. LG Chem has panels which are more efficient (or at least they will have ones later in 2013) than the new Tridonic module.

LG Chem sent us an update on their OLED lighting program, with some very exciting news. Besides planning flexible OLED lighting panels in July 2013 (I already posted about this earlier), LG says they have successfully developed high efficiency OLED lighting panels (80 lm/W, similar to CFLs) that will enter mass production in July 2013 (together with the flexible panels). These will be the world's most efficient OLED panels (beating LG Chem's current 60 lm/W panels).

The upcoming 80 lm/W will feature 20,000 hours lifetime (LT70), 3000K color temperature, brightness of 75 lumens (3000 cd/sqm) and a CRI of 85. The first 80 lm/W panels will be 100x100 mm in size and only 1.1 mm thick (thinner than LG's current panels which are 1.8mm thick). LG says that these panels will have a surface temperature of 26 degrees - roughly around room temperature (this is better than their current panels).

Panasonic Idemitsu OLED Lighting (PIOL) unveiled new OLED lighting panels and also revealed the company's roadmap till 2018. The company currently produces 100x100 mm panels, and they are now showing new 150x50 mm and 200x50 mm panels that will be released in the spring of 2013.

The new panels will offer the same performance as PIOL's current panels: 10,000 lifetime (LT70), 30 lm/W and color temperatures of 3000K, 4000K and 5000K. PIOL confirmed that the only difference to the current panels is the shape. PIOL's panels have a high CRI (over 90) and they mostly target museums and exhibitions (some of the panels have already been used in at least two museums: Kyoto's MOMAK museum and Panasonic's own Shiodome museum).

Update: Kyushu University published an interesting video with more details about this new technology

Researchers from Japan's Kyushu University developed new efficient rare-metal free OLED emitter materials based on dicyanobenzene derivatives. They say that these new materials (which they call hyperfluorescence) are as efficient as phosphorescent OLEDs, but are cheaper (about 1/10th of the cost) because they do not require rare metals.

The researchers say that they are now seeking to collaborate with Japanese makers to commercialize this technology "at an early date". They already created some display prototypes with the new materials (see photo above).

Researchers from the US DOE's Ames Laboratory have developed a new OLED display anode ITO alternative based on a PEDOT:PSS polymer. This material is basically not conductive and transparent enough to be used in OLEDs, but by using a multi-layered technique and special treatments the researchers were able to fabricate PEDOT:PSS OLEDs that are actually 44% more efficient than ITOs, and are transparent enough. This is in fact the most efficient transparent anode material ever developed.

PEDOT:PSS is also flexible, which means it can be used to make flexible OLED panels, unlike ITO. There's a lot of interest in replacing ITO which is expensive, not flexible and not environmental friendly. Just last month there were two interesting announcement regarding ITO alternatives in OLED lighting: Konica Minolta and NEDO's new replacement film and Heraeus' new polymer OLED HIL-E materials.