Zenith Chromacolor tubes...--why are they so much BETTER?

[rca2000]

Just WHAT did Zenith do--to make the CC CRT's SO great?

Over the weekend..at the ETF while watching a CRT being rebulit for the FIRST time there...I asked Jerome Halpren (sp) about what it was that made Trinitron tubes un-rejuvinatable. he said the cathode coating is VERY thin to begin with and so...there is just NOTHING to "uncover" when trying to bring one back, and also...he suspected the very close spacing of the single-gun design to the the cathodes would NOT allow restoring current to properly flow...and so nothing can be "restored". Makes sense to me..

On the OTHER hand...something i FORGOT to ask...was about the Zenith Chromacolor delta tubes. I wanted to know what is DIFFERENT about them...that makes them so much BETTER..it seems...than almost ANY other tube.. to last so long and STILL look SO good...after all of these years.

I suspect it is the OPPOSITE situation to Sony...likely real thick coating on the cathode which just does NOT wear out very fast. Does anyone know if this is right--or is it something else?