Explanatory information about standard ISO 9241-307
Explanatory information about
standard ISO 9241-307
Permanently unlit or lit pixels
Today's production techniques cannot guarantee an absolutely fault-free screen display. Depending
on the total number of pixels (resolution), there may be a few constantly lit or unlit pixels or subpixels.
The maximum permitted number of faulty pixels is stipulated in the international standard
ISO 9241-307. In accordance with standard ISO 9241-3, LCD monitors by Fujitsu comply with Class
II for low resolutions and Class I for resolutions of 1680 x 1050 (1764000 pixel) and higher.
A ﬂat-screen monitor with a resolution of 1280 x 1024 has 1280 x 1024 = 1310720 pixels. Each pixel
consists of three subpixels (red, green and blue), so there are almost 3.9 million subpixels in total.
According to ISO 9241-3 (Class II), a maximum of 3 lit and 3 unlit pixels plus 7 lit or 13 unlit subpixels,
or a corresponding combination, may be faulty (1 lit subpixel counts as two unlit subpixels).
A pixel consists of 3 subpixels, normally red, green and blue. A pixel is
the smallest element that can be generated by complete functionality of
A subpixel is a separately addressable internal structure within a pixel that
enhances the pixel function.