Wladimir Baranoff-Rossiné called his main invention an “optophone.” In various sources it also appeared as “optophonic piano”, “visual piano”, “colour piano”, “chromotrope”. Over time, these names were used less and less. To control individual elements of the “optophone” – mirrors, prisms, filters, disks with images printed on them, Baranoff-Rossiné used three octaves of a piano keyboard. For uninitiated viewers and listeners, the presence of a keyboard had a deceptive effect; many thought that sound was coming from the “optophone”. However, the structure of the instrument was not designed for producing sound. Work on the “optophone” began in 1912. However, the author received the patent much later. The grant of a patent for a “projection device for reproducing changing light and colour impressions (chromotrope)” by Baranoff-Rossiné was published in the Bulletin of the Committee for Inventions of the USSR in March 1925, although the application certificate was registered on September 18, 1923.
Links to Third-Party Publications:
Kolganova O. V. Light-colour projection devices by Wladimir Baranoff-Rossiné and G. Gidoni (1920–1930s) // The Art and Science of Television. 2021. No. 17.4. pp. 33–62. https://www.academia.edu/73464153/Wladimir_Baranoff_Rossine_s_and_Grigory_Gidoni_s_Light_and_Colour_Projectio n_Devices_1920s_1930s_Light-coloured_projection_devices_In_Baranov_Rossin_and_G_Gidoni_1920s_1930s_years_
