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 2560 x 1440 has 2560 x 1440 = 3686400 pixels. Each pixel
consists of three subpixels (red, green and blue), making a total of about 11,1 million subpixels.
According to ISO 9241-3 (Class I), a maximum of 2 lit and 2 unlit pixels plus 9 lit or 18 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.
Fujitsu
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