Feb 23, 2010

The DisplayBlog and DisplayMate are working on an interesting series of tests for Google's Nexus One phone AMOLED display and the iPhone's 3GS display. It's not finished yet, but they have posted the first tests of the AMOLED display. There's a lot of technical information, but here are the main conclusions:

  • The OLED is 800x480, but uses PenTile technology, that has two-thirds of the total number of sub-pixels found on an 800x480 LCD, so it won’t be quite as sharp as a typical 800x480 display.
  • The display has only 16-bits color depth, with just 32 or 64 intensity levels. DisplayMate say this is unacceptable for a high performance phone such as the Nexus One. The colors are coarse and inaccurate as a result. 
  • The display is excellent for text, icons and menu graphics, but poor for image and awful for resolution scaling. The problem with resolution scaling lies in the Android OS which uses a "laughably primitive scaling algorithm".
  • The peak white brightness is just 229 cd/m2 which is rather poor.
  • The black brightness is outstanding (0.0035 cd/m2) - so dark it is hard to measure or even detect.
  • The contrast ratio (65416) is great, the highest they have measured for a production display.
  • The screen reflectance is relatively high and washes out the image, makes it hard to view in bright conditions. 
  • The phone uses Dynamic Color and Dynamic Contrast which results is exaggerated colors and stretching of images.

DisplayMate says that "if the Nexus One display were an LCD it would rank among the worst displays we have ever seen in a shipping product. Some of this is undoubtedly due to poor integration of the display hardware with the Android OS and software. Much of it, however, is simply due to very poor factory calibration and quality control, especially with the lack of any credible color and gray scale calibration. Most likely the display sub-assembly was just slapped in as-is into the phone".

Comments

In the pictures above you can quite clearly see the Nexus One has clearer and higher colour definition than the iPhone it is being compared to. The iPhone is old, the software outdated, and the same software is being installed into the iPamper sorry iPad.
The Nexus One far outstrips the iPhone. Which? magazine in the UK did a similar test and the Nexus One came out on top. Difference being Which? are impartial. Don't believe everything you read.

I've had the same problem with false contouring and image noise as seen on the Sunset on Mars picture above, it almost only show on grey cloudy pictures.

The funny thing is that it only looks that bad on the stock nexus one gallery app. I dont get any noise, contouring or distortion using a different app for viewing the picture on the same phone. In other words its a software and not a hardware issue, hopefully the gallery app will be patched soon.

Comparing it side by side, the screen on my nexus one looks a lot better than the one on my girlfriends iphone 3gs.

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