Medion MD 20120, Instruction Manual

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Pixel errors in the TFT monitor
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Types of pixel error:

Type 1:
Pixels shining for a long time (bright, white point), although
not activated.
A white pixel arises because of the illumination of all three sub-pixels.

Type 2:
Pixels not shining (dark, black point), although activated

Type 3:
Abnormal or defective sub-pixels coloured red, green or blue (e.g. shining for a long time with half
brightness, not lighting one colour, flashing or flickering, but not Type 1 or 2)
Addition: Cluster of Type 3 (= failure of two or more sub-pixels in a block of 5 x 5 pixels. A cluster is a field of 5 x 5
pixels (15 x 5 sub-pixels).
Classes of pixel error:
Error Class Type 1 Type 2 Type 3 Cluster of Type 3
I 0 0 0 - 0
II 2 2 5 - 2
III 5 15 50 5
IV 50 150 500 50
The permitted number of errors of the types specified above in each class of error relates to a million pixels and
must be converted in accordance with the physical resolution of the display.
A maximum permitted number in Error Class II follows from this:
For a resolution of M. pixel Sub-pixels (Type, see
above)
1024 x 768 (15") 0.786432 2.359296 2 2 4 - 2
1280 x 1024 (17,18, 19") 1.310720 3.932160 3 3 7 - 3
1600 x 1200 (19“) 1.920000 5.760000 4 4 10 - 4
1440 x 900 (19“ wide) 1.296000 3.888000 3 3 7 - 3
1680 x 1050 (20“ wide, 22“ wide) 1.764000 5.292000 4 4 10 - 4
Error Class I is only used in the case of special applications, e.g. in the medical sector, and is associated with
corresponding supplementary costs. Error Class II has become established as the standard for manufacturers
conscious of quality and with very good display units.
Example 1:
A 15” XGA display unit consists of 1024 horizontal and 768 vertical scanning elements (pixels), that is 786,432
pixels in total. This gives a factor of about 0.8 in relation to one million pixels.
Error Class II therefore allows two errors of both Type 1 and Type II, four Type 3 errors and two Type 3 clusters.
Example 2:
A 17” SXGA display unit consists of 1280 horizontal and 1024 vertical scanning elements (pixels), that is 1.31
million pixels in total. This gives a factor of about 1.31 in relation to one million pixels.
Error Class II therefore allows three errors of each Type I and Type II, seven Type 3 errors and three Type 3 clusters.
However, this does not usually concern a guarantee case.
A guarantee may possibly exist of the number of errors given above is exceeded in a category.