just wondering. At least are they aperture grill?

At least are they aperture grill?
No need for aperture grill or shadow mask in one color projection tubes.

Each tube is a separate color. All conventional color tubes have all three colors in each tube, and the purpose of the aperture grille (Trinitron) or shadow mask (all others) is to keep the three separate electron beams (for red, green, and blue) from illuminating any
phosphor other than their own designated color phosphor, by casting a shadow from
that gun over the other two phosphor colors.

As projection CRTs have only ONE color of phosphor per tube, there is not the slightest
reason whatsoever to put ANYTHING between the electron gun and the phosphor layer.

CJ

nothing to add - just have a look at my avatar picture to see a diagram of the Trinitron technology ;)