Philips BDL4235DL/00 D-Line Display

minimumdistancebetweendarkdots

Becausepixelandsub-pixelsdefectsofthesametypethatarenearbyoneanothermaybemorenoticeable,Philipsalsospeciestolerancesforthe

proximityofpixeldefects.Inthetablebelowyoucanndspecicationsabout:

• Allowedamountofadjacentdarkdots=(adjacentdarkdots=1pairofdarkdots)

• Minimumdistancebetweendarkdots

• Totalno.ofalldefectivedots

Inordertoqualifyforrepairduetopixeldefectsduringthewarrantyperiod,aPDP/TFTpanelinaPhilipsPlasma/LCD-displaymusthavepixelorsub-

pixeldefectsexceedingthetoleranceslistedinthefollowingtable.

Darkspotsorpatchesmayoccasionallyappearonsomeliquidcrystaldisplay(LCD)panels.ThisisknownwithintheindustryasMura,whichisaJapanese

termfor“unevenness.”Itisusedtodescribeanirregularpatternorareainwhichunevenscreenuniformityappearsundercertainconditions.Muraisa

resultofthedeteriorationoftheliquidcrystalalignmentlayerandismostcommonlycausedbylong-termoperationunderhighambienttemperatures.It

isanindustry-widephenomenonandMuraisnotrepairable.Itisalsonotcoveredbyourwarrantyterms.

MurahasbeenaroundsincetheintroductionofLCDtechnologyandwithscreensgettingbiggerandinoperation24/7,manydisplaysarerunninginlow

lightconditions.ThisalladdstothepossibilityofMuraaffectingdisplays.

TherearemanysymptomsofMuraandalsomultiplecauses.Severalofthesearelistedbelow:

• Impuritiesorforeignparticlesinthecrystalmatrix

AlthoughwecannotguaranteethecompleteeradicationofMuraeverytime,ingeneraltheappearanceofMuracanbeminimizedbythesemethods:

• Lowerthebacklightbrightness

• Useascreensaver

• Reducetheambienttemperaturearoundtheunit