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.
R G B
R G B
R G B
R G B
R G B
R G B
1
2
1 = Pixel
2 = Subpixel
Pixel
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
the display.
Subpixel
A subpixel is a separately addressable internal structure within a pixel that
enhances the pixel function.
Pixel fault
All 3 subpixels are lit/unlit. The result is a brighter or darker pixel.
Subpixel fault
Only one subpixel is lit/unlit. The result is a pixel with missing colours.
The maximum permitted number of faulty pixels is stipulated in the international standard
ISO 9241-307. The LCD displays from Fujitsu comply to at least Class I. Fujitsu guarantees
displays that are free of pixel faults, so that only subpixel faults may occur.
Examples
:
A
fl
at-screen monitor with a resolution of 1280 x 1024 has 1280 x 1024 = 1,310,720 pixels. Each
pixel consists of three subpixels (red, green and blue), making a total of about 3.9 million subpixels.
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
fl
at-screen display with a resolution of 1920 x 1200 has 1920 x 1200 = 2304000 pixels. Each
pixel consists of three subpixels (red, green and blue), making a total of about 6,9 million subpixels.
According to ISO 9241-3 (Class I), a maximum of 2 lit and 2 unlit pixels plus 5 lit or 11 unlit subpixels,
or a corresponding combination, may be faulty (1 lit subpixel counts as two unlit subpixels). Because
Fujitsu supplies displays that are free of pixel faults, only subpixel faults enter into the evaluation.
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Fujitsu
