Trinitron is arguably the best consumer CRT (Cathode Ray Tube) technology available. The technology was developed by Sony Corporation, who owns complete rights to it. The Trinitron design has helped the company lead the market in the manufacturing of TVs and monitors for many years. The difference between a Trinitron tube and most other tubes is that the Trinitron uses an aperture grille instead of a shadow mask for creating the image on the screen.
An aperature grille consists of wires stretched vertically down the screen (allowing for a vertically flat screen). A shadow mask is basically a metal plate with holes in it, where light can pass through. Because Trinitron monitors are vertically flat, they have less image distortion and less glare than most other monitors. If you look very closey at a Trinitron screen, you should see one or two very thin dark horizontal lines that span the width of the screen. These lines are small wires that support the aperture grille.