The Arri Group has been the largest worl wide supplier of high quality motion picture film equipment since 1917. Arri, named after founders August Arnold and Robert Richter, is the largest manufacturer of professional motion picture equipment, film cameras (16, 35, and 65/70 mm) and cinematic lighting equipment in the world. In recent years they have expanded into post-production equipment with the Arrilaser, and in 2000 purchased Moviecam to refine their new camera platform Arricam. In 1937 the Arri Group introduced the world's first reflex mirror shutter in the Arriflex 35 camera, an invention of their longtime engineer Erich Kaestner. This technology employs a rotating mirror that allows a continuous motor to operate the camera while providing parallax-free reflex viewing to the operator, and the ability to focus the image by eye through the viewfinder, much like an SLR camera for still photography. This technology is still employed today in almost every motion picture camera..