#11484 NORM 1.75-so: XO-1.75 OS12 grainy moving pattern on screen

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Mon Feb 6 03:03:05 EST 2012

#11484: XO-1.75 OS12 grainy moving pattern on screen
           Reporter:  tonyforster   |       Owner:               
               Type:  defect        |      Status:  reopened     
           Priority:  normal        |   Milestone:  1.75-software
          Component:  not assigned  |     Version:  not specified
         Resolution:                |    Keywords:               
        Next_action:  never set     |    Verified:  0            
Deployment_affected:                |   Blockedby:               
           Blocking:                |  

Comment(by martin.langhoff):

 Is this still happening, on OS26? Can you give us more information so we
 can understand what you are reporting?

 You have written:
  * grainy moving pattern on screen
  * getting occacional moire like moving patterns more visible on large
 blocks of colour
  *  This will not capture in a screenshot, its like the flicker of a
 normal fluorescent light in your peripheral vision. I guess the screen
 refresh is just visible at times, though why you would notice it when the
 display is constant is a bit of a mystery. Maybe the brightness of pixels
 changes marginally during rewrite or maybe the processor is putting a bit
 of noise on the voltage rail.

 What steps can we follow to see it, or to increase the chances of seeing

  * Any "content" on the screen that helps?
  * Lighting conditions? You can sure see some oddities if you have a
 strong, hard light hitting the screen in an acute angle. Other oddities
 may appear if you have fluorescent lighting.
  * Acute angle between your line of vision and the LCD?
  * Looking at it straight or trying to catch it with your peripheral
  * Will a camera capture it?

Ticket URL: <http://dev.laptop.org/ticket/11484#comment:10>
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