Incandescent light bulb granted a Hungarian patent (No. 34541) for a tungsten filament lamp that lasted longer and gave brighter light than the carbon filament. Tungsten filament lamps were first marketed by the Hungarian company Tungsram in 1904. This type is often called Tungsram-bulbs in many European countries. Filling a bulb with an inert gas such as argon or nitrogen slows down the evaporation of the tungsten filament compared to operating it in a vacuum. This allows for greater temperatures and therefore greater efficacy with less reduction in filament life. In 1906, William D. Coolidge developed a method of making "ductile tungsten" from
Phase-out of incandescent light bulbs to one-third the electric power, and may last eight to fifteen times longer. Newer phosphor formulations have improved the perceived color, with "soft white" CFLs judged subjectively similar to standard incandescent lamps. Objections more specifically relating to compact fluorescent light bulbs include the different quality of light produced by phosphor-based lamps compared to incandescent lamps and that compact fluorescent light bulbs contain small amounts of mercury, a potent neurotoxin, which is especially dangerous to children and pregnant women, and made more serious by the confined area mercury would be dispersed in the event of a breakage indoors. Environmental concerns about