Viewsonic CDE4302 사용자 설명서
17
8. Panel Defect Policy
8.1. MURA
Dark spots or patches may occasionally appear on some liquid crystal display (LCD) panels.This is known
within the industr y as Mura, which is a Japanese term for “unevenness.” It is used to describe an irregular
pattern or area in which uneven screen uniformity appears under certain conditions. Mura is a result of the
deterioration of the liquid crystal alignment layer and is most commonly caused by long-term operation under
high ambient temperatures. It is an industry- wide phenomenon and Mura is not repairable. It is also not
covered by our warranty terms.
Mura has been around since the introduction of LCD technology and with screens getting bigger and in
Mura has been around since the introduction of LCD technology and with screens getting bigger and in
operation 24/7, many displays are running in low light conditions.This all adds to the possibility of Mura
affecting displays.
HOW TO SPOT MURA
There are many symptoms of Mura and also multiple causes. Several of these are listed below:
HOW TO SPOT MURA
There are many symptoms of Mura and also multiple causes. Several of these are listed below:
• Impurities or foreign particles in the crystal matrix
• Uneven distribution of LCD matrix during manufacturing
• Non-uniform luminance distribution of the backlight
• Panel assembly induced stress
• Flaws within the LCD cells
• Thermal induced stress - high temperature operation over long periods of time
HOW TO AVOID MURA
Although we can not guarantee the complete eradication of Mura every time, in general the appearance of
Although we can not guarantee the complete eradication of Mura every time, in general the appearance of
Mura can be minimized by these methods:
• Lower the backlight brightness
• Use a screen saver
• Reduce the ambient temperature around the unit
8.2. Image Sticking
Image sticking judgment standard
Initial Pattern
Time
Judgment PTN
Judgment standard
Mosaic (8×6)
1Hr
127 Gray
• isappear within 10Min’
• ok level: under 2 leve
• ok level: under 2 leve