Carbonized cellulose filament bulb, ca. 1895Item 74867 info
Maine Historical Society
Some of the filament materials were chosen to make light bulbs more efficient – producing more light while using less energy.
Though Edison achieved success with a carbonized bamboo filament, research continued for filaments that lasted longer and burned more efficiently.
Among the filament materials that proved most successful was carbonized cellulose, which became the industry standard for almost 20 years. This produced 2.7 lumens per watt.