Color crt question???

[old_tv_nut]

I recently came across this patent for an all-sulfide screen.

[Pete Deksnis]

Originally Posted by old_tv_nut

I recently came across this patent for an all-sulfide screen.

Interesting that in 1959 -- the date of the application -- the CIE color coordinates for green were still the 1953 NTSC values. Although the author adds the caveat 'most' when referring to color CRTs available then, he does specify both the 21AXP22 and the 21CYP22 as meeting the original NTSC green standard. There is documentation that indicates the 21AXP22 does, but this is the first time I have seen something including the 21CYP22 as well. I suspect the 21CYP22A however does not, as this was touted as a 'brighter' tricolor tube but with greater lag, IIRC.