Strip mask tubes are a variant of the shadow mask tube, the best known of which is the trinitron. Strip mask tubes are cathode ray tubes( CRT) for color displays as used in televisions, monitors and screens.
In the strip mask, the mask is strip-shaped, in the form of narrow vertical metal strips. Similarly, the phosphor layer consists of phosphors arranged in strips, which emit red, green and blue when excited. The electron beams for the three primary colors, due to the striped masks, only hit the phosphors they are supposed to excite. The thin metal strips prevent the electron beam from hitting neighboring phosphor strips, which could cause the color emission color distortions.
The strip mask technique has the advantage over the shadow mask that it is brighter and sharper.