Flat screen televisions (TV) and computer screens that are larger than conventional models but weigh less could be on sale within two years at affordable prices, say scientists at Canon's Japanese research laboratories. Canon has developed a new type of flat-screen and aims to launch a 40-inch TV that is less than 4 inch deep. Most of the current flat-screen systems use gas-plasma or liquid crystal display (LCD) technology. Canon will use a system called surface-conduction electron-emitter display (SED). The advantages that SED offers over LCDs are lower costs and voltage and thus less power consumption, which makes it useful for notebook PCs.