Defective Pixel Specifications
What is a Bright and or a Dark Dot?
Due to the cost of producing LCD panels, panel manufacturers have set limits as to how many defective dots (or sub-pixels) are deemed to be acceptable for a standard LCD panel. The goal in setting such limits is to maintain a reasonable price of the panel while minimising distraction from defective dots.
A pixel (picture element) consists of one red and one green and one blue dot or sub-pixel. A standard 15" LCD panel with a resolution of 1024 x 768 pixels has a total of 786,432 pixels or 2,359,296 dots. 17", 18.1" or 19" LCD panels have almost 4 million dots, while a 20.1" LCD has more than 5.5 million dots.
Each dot is driven by an individual transistor. If a transistor becomes defective, the corresponding dot may be permanently lit (a bright dot) or may not light (a dark dot). For a manufacturer to guarantee that all LCD panels are totally defect free would lead to a much higher cost of manufacture.
1.
Total Defective Dots
The specifications for the number of defects that are deemed to be acceptable for each size of LCD panel :
LG India