[Galaxy S 4 General] BarryH_GEG:
Brightness and Power Efficiency

OLED displays are generally not as bright as the brightest LCD displays

. There are two reasons for this: first, while OLED power efficiency has been steadily improving they are not yet as power efficient as the best LCDs. Second: there is a marketing obsession for producing ultra thin and light weight Smartphones, which sacrifices much needed battery power. Since the display often uses 50 percent or more of the total Smartphone power, various display power management schemes are frequently used. The Galaxy S4 uses one innovative approach to overcome this –

when Automatic Brightness is turned on, the [SGS4's] Peak Brightness becomes significantly brighter in high ambient lighting than is possible with Manual Brightness, up to as high as 475 cd/m2, which is 34 percent higher than is possible with Manual Brightness. This is done so that users can’t permanently set the brightness to very high values, which would run down the battery quickly.

Performance in High Ambient Lighting

Smartphones are never used in the dark. In fact, they are often used in very bright ambient lighting, which can significantly degrade and wash out their image and picture quality.

The Galaxy S4 performs very well in high ambient lighting in spite of its typically lower screen brightness because it has one of the smallest screen Reflectance values of any display we have ever tested

, and its

more saturated colors can help cut through the reflected light glare

. When Automatic Brightness is turned on, the screen brightness increases considerably at high levels of ambient lighting as mentioned above.

The Galaxy S4 is then comparable or brighter than most LCD Smartphones, but still 15 percent less than the much smaller iPhone 5, which is the brightest Smartphone we have tested.

Comparing Displays on the Galaxy S III and Galaxy S4

The Galaxy S4 display is a major enhancement and improvement over the Galaxy S III

– a good reason to consider trading up. The screen has Full HD 1920x1080 resolution with more than double the number of pixels and with 44 percent higher Pixels Per Inch than the Galaxy S III.

It is 25 percent brighter (and up to 68 percent brighter with Automatic Brightness) and the display is 20 percent more power efficient.

The Galaxy S4 also has 5 user selectable Screen Modes and delivers much better picture quality and color accuracy.

Comparing the Galaxy S4 with the LCD Display on the iPhone 5

The iPhone 5 is now more than half way through its product cycle, which is important to keep in mind for our comparison. However, high-end LCDs like the iPhone 5 are a very mature and refined display technology, so other than screen size, resolution, and the Pixels Per Inch not much is likely to change in the next generation, no matter what Apple decides to do.

The iPhone 5 is significantly brighter than the Galaxy S4, particularly for screens with mostly peak white backgrounds.

Its color calibration is a bit better, although the Galaxy S4 has a more accurate White. The Galaxy S4 has a much bigger screen, higher resolution, higher PPI, much darker blacks, and better screen uniformity than the iPhone 5. They each have their own particular strengths and weaknesses, but if you scan our color coordinated Comparison Table below, both displays are quite good and comparable overall – so it’s currently a tie – we’ll see how they both evolve and improve in the next generation…

Conclusions: An Impressive OLED Display…

The Galaxy S4 continues the rapid and impressive improvement in OLED displays and technology. The first notable OLED Smartphone, the Google Nexus One, came in decidedly last place in our 2010 Smartphone Display Shoot-Out.

In a span of just three years OLED display technology is now challenging the performance of the best LCDs

. Each have their own particular strengths and weaknesses, but if you scan our color coordinated Comparison Table, both displays and technologies perform quite well and look quite good and comparable overall – we’ll see how they both evolve and improve in the next generation, which we consider next…

The biggest challenge for OLEDs is continuing to improve their power efficiency and full screen peak brightness. We measured an impressive 20 percent improvement in power efficiency between the Galaxy S4 and S III, and a 25 percent increase in brightness (and up to 68 percent with Automatic Brightness). If this keeps up then OLEDs may pull ahead of LCDs in brightness and power efficiency in the near future…

http://www.displaymate.com/Galaxy_S4_ShootOut_1.htm

Dr. Raymond Soneira - Founder, President and CEO of DisplayMate is an internationally recognized research scientist with a distinguished career that spans physics, computer science, and television system design. Dr. Soneira obtained his Ph.D. in Theoretical Physics from Princeton University, spent 5 years as a Long-Term Member of the world famous Institute for Advanced Study in Princeton, another 5 years as a Principal Investigator in the Computer Systems Research Laboratory at AT&T Bell Laboratories, and has designed, tested, and installed color television broadcast equipment for the CBS Television Network Engineering and Development Department. He has authored over 35 research articles in scientific journals in physics and computer science, including Scientific American.