Today, 115 years ago, on August 27, 1910 (Lunar Calendar July 23, 1910), Edison invented sound film. Edison took a break in the lab. On August 27, 1910, Thomas-Alva-Edison announced his latest invention: sound film. Some selected audiences were invited to the Edison Laboratory in West Orange, New Jersey, to watch the film that connected the sound of the sound and images on the film camera. Others also wanted to invent the sound film, but no success. Edison's contribution was that he recorded sound and images simultaneously at the same time, while this was not possible for others. By operating a sound and photographic machine, Edison could let actors move back freely in the process of photography, which in the past was fundamentally impossible for love to change. Edison spent two years on sound lights, and he successfully used