Sony Indextron SCORE!!!!!!

[wa2ise]

Originally Posted by Dave A

To save some search time...the Indextron tube is a straight-line stripe from top to bottom with a black guard band in-between each stripe. No shadow mask or wire mask. Just a RGB switched color beam going to it's matching color stripe.

Black/Red/Black/Blue/Black/Green and so on. It knows where it is by sensing the green stripe from the rear of the tube.

One big problem with this scheme is that you could not allow the tube to have deep blacks in the picture. Else the indexing looses track of which stripe the electron beam will be hitting when the video image scans out of a black region in the picture. Thus a lower limit on darkness, and the picture looks washed out, kinda like older LCD displays where the LCD pixels couldn't block all of the backlight from getting thru in black areas of the picture.

It did get rid of that PITA convergence chore in manufacturing. Which would cut manufacturing costs.

The width of the stripes on your Indextron reminds me of the coarseness of some GE Portacolor CRTs.