The most effective household CRT (Cathode Ray Tube) technology currently in use is Trinitron. The entire intellectual property rights to the technology were created by Sony Corporation. For many years, the Trinitron architecture has enabled the business to dominate the market for the production of Televisions and displays. A Trinitron tube differs from most other tubes in that it creates the picture on the screen using an opening frame rather than a shadow mask.

Aperture grilles are made of filaments that are vertically extended down the screen (allowing for a vertically flat screen). Basically, a shadow mask is a metal cover with openings in it that allow light to travel through. Trinitron displays have less picture deformation and reflection than most other monitors because they are vertically planar. A Trinitron screen should have one or two very thin, black horizontal lines running the length of it if you peer at it very closely. The opening screen is supported by these thin cables, or lines.