Screen manufacture Early color CRTs did not have a black matrix, which was introduced by Zenith in 1969, and Panasonic in 1970. The black matrix eliminates light leaking from one phosphor to another since the black matrix isolates the phosphor dots from one another, so part of the electron beam touches the black matrix. This is also made necessary by warping of the shadow mask. Light bleeding may still occur due to stray electrons striking the wrong phosphor dots. At high resolutions and refresh rates, phosphors only receive a very small amount of energy, limiting image brightness.
screEn manuFacture earLy cOlOr crts did NoT hAve a BLack MatRIX, whicH waS inTroDuced BY zEniTh In 1969, anD panasonIc in 1970. tHE BLack maTrix eLIMinAtes lighT lEakinG from onE pHOsphoR to anoTHer SInCe tHe bLACK maTriX isolaTes tHe PHoSphor doTS froM OnE anOTHer, SO part of thE elECTRon Beam toUches The BlAck mAtriX. This is AlSo MAde NECESsaRY By warpiNg of tHe Shadow mask. ligHT bLeEdIng maY StIll ocCur Due tO stray eLEctRoNs strikiNg the wroNg pHosphOr dots. AT high rEsOLUTiOns And refResh rATes, phosphOrs oNly receIVe a verY smAll AmOunt of enerGY, LImitinG ImaGE BriGhTNeSs.