Through the 1970s the hand-held electronic calculator underwent rapid development. The red LED and blue/green vacuum fluorescent displays consumed a lot of power and the calculators either had a short battery life (often measured in hours, so rechargeable nickel-cadmium batteries were common) or were large so that they could take larger, higher capacity batteries. In the early 1970s liquid-crystal displays (LCDs) were in their infancy and there was a great deal of concern that they only had a short operating lifetime. Busicom introduced the Busicom "LE-120A "HANDY"" calculator, the first pocket-sized calculator and the first with an LED display, and announced the Busicom "LC" with LCD. However, there were problems with this display and the calculator never went on sale. The first successful calculators with LCDs were manufactured by Rockwell International and sold from 1972 by other companies under such names as: Dataking "LC-800", Harden "DT/12", Ibico "086", Lloyds "40", Lloyds "100", Prismatic "500" (a.k.a. "P500"), Rapid Data "Rapidman 1208LC". The LCDs were an early form using the "Dynamic Scattering Mode DSM" with the numbers appearing as bright against a dark background. To present a high-contrast display these models illuminated the LCD using a filament lamp and solid plastic light guide, which negated the low power consumption of the display. These models appear to have been sold only for a year or two.