What is BenQ's dead pixel policy?

04-09-2018

BenQ LCD Monitor Pixel Policy

Panel manufacturers set limits as to how many defective dots (or sub-pixels) are deemed to be acceptable on any LCD panel.

BenQ’s manufacturer warranty covers any defects that exceed the defect specifications described in this document.

LCD displays are made of pixels. Each pixel is made up of a red, green and blue sub-pixel, each sub pixel are driven by an individual transistor. If a transistor becomes defective, the corresponding dot may be permanently light (bright) or may not light (dark). Independently of the brand and the manufacturer, it is common for one or more sub-pixels to become fixed in an unchanging state.

The defective pixel/sub-pixel phenomenon is as follows:

(1) Color white - a bright/hot sub-pixel (always ON)
(2) Color black - a dark sub-pixel (always OFF)
(3) Color red, green or blue - a stuck sub-pixel (always ON or always OFF)

Pixel Structure with Illustrations:

Full-pixel vs. sub-pixel

A full pixel consists of one red, green, and blue sub-pixel.

What is a bright sub-pixel?

A bright sub-pixel is one that is fully lit. In the following example the blue sub-pixel remains lit even when the surrounding sub-pixels are unlit.

What is a dark sub-pixel?

A sub-pixel that is always colored on a white background.

Bright sub-pixel

Dark sub-pixel

Maximum Number of Defects

The specifications for the number of defects that are deemed to be acceptable for each size of LCD panel are:

Panel Type	Native Resolution	Bright sub-pixel	Dark sub-pixel	Total Allowable Sub-pixel
Smaller than FHD	Smaller than 1920x1080	3	3	5
Full HD (FHD)	1920x1080 (1080p)	2	5	5
Quad HD (QHD)	2560x1440 (1440p)	2	5	5
Ultra HD (UHD)	3840x2160 (4K)	2	5	5

Note: Specification is subject to change without notice and may vary from different regions.