Colour Tv screens
Laser, radar
Photographic cameras lenses
Refractory bricks

Yttrium is quite used in producing alloys, optical glasses and ceramics. It is also used in special catalysts and in opto-electronic devices such as lasers, filters for microwaves and europium "phosphorus" for the red color in television sets. Some of its isotopes are radioactive, being used in cancer radiotherapy.