'Mazda' tungsten filament bulb, ca. 1935
Item 74871 info
Maine Historical Society
William D. Collidge, working for General Electric, found that by taking the sintered tungsten filament and forcing it though increasingly small dies, a wire could be produced that was flexible, yet strong.
This material was used in light bulbs beginning in 1911 and is still used in incandescent bulbs today. Many methods were tried to reduce the glare of light bulbs including outside frosting, either by etching or coating the bulb, and the use of white glass for bulbs.
A method for frosting was developed in 1925. This lamp produced 10.1 lumens per watt.
Item 11 of 14
