The Toshiba Corporation was founded in 1939 when 2 Japanese companies were merged. Tanaka Engineering Works which manufactured telegraph equipment and Hakunetsusha which produced incandescent electric lamps. During the 1940's and 50's Toshiba grew rapidly by growth and acquisitions and by the 70's was involved in a large range of industries including electrical, chemical, lighting, information technology and transportation. Toshiba was responsible for numerous Japanese inventions between 1940 and 2005 including radar, digital computers, microwave ovens, video phones, the MRI system, personal laptop computers, DVD and HD DVD. Today Toshiba focuses on personal computers, computer parts and printers, up until recently they were the 5th largest PC vendor after HP, Dell, Acer and Lenovo. Other areas of income include High Definition and 3D TV's, Appliances, Semiconductors and Power Systems and Electronic Devices.