A TV picture tube (CRT) that has a flatter viewing surface than the traditional rounder tube. Up to 30% more glass is used to make the screen flatter. Also known as a "flat screen," "flat face CRT" or "flat square tube (FST)", the flat CRT provides less distortion at the edges and is the preferred design.
Flat and Thin
Flat CRTs are considerably thinner than earlier CRTs, although still not as thin as flat panel displays. By the way, LCD and plasma displays are also called "flat screens." See flat panel display
and flat panel TV
A Flat and Thin CRT
This is the picture tube outside the case of Samsung's flat and thin TV (viewed from the top). Introduced in 2005, it was flatter and considerably thinner than earlier CRT TVs, enabling a 32" HDTV set to be only 15" deep. All CRTs, flat, thin and otherwise, gave way to LCD and plasma panels.