Edison and his team of researchers in Edison’s laboratory in Menlo Park, N.J., tested more than 3,000 designs for bulbs between 1878 and 1880. In November 1879, Edison filed a patent for an electric lamp with a carbon filament.
Edison and his team of researchers in Edison’s laboratory in Menlo Park, N.J., tested more than 3,000 designs for bulbs between 1878 and 1880. In November 1879, Edison filed a patent for an electric lamp with a carbon filament.
