Petro Vlahos (Greek: Πέτρος Βλάχος; August 20, 1916 – February 10, 2013)[1][2] was an American engineer and inventor, considered to be one of the pioneering scientific and technical innovators of the motion picture and television industries.

Vlahos was not the first to use the blue-screen technology — it was invented by Larry Butler for the 1940 filming of The Thief of Bagdad — but he made the process much more realistic and scientific.

He created a system called the sodium vapor process first for The Parent Trap and The Absent-Minded Professor and later the Disney musical Mary Poppins (1964) which would win him an academy award.

Vlahos' breakthrough was to create a complicated laboratory process which involved separating the blue, green and red parts of each frame before combining them back together in a certain order.

His company's first Ultimatte units were analog "black boxes" which later evolved into advanced, real-time digital hardware and computer software products.