"rear projection"的定义和意义

What is "rear projection"?

Rear projection is a special effects technique used in film and photography where a pre-recorded background image or video is projected onto a screen from behind. In this setup, actors or objects are positioned in front of the screen, and the camera is placed in front of the actors. The projector, hidden from the audience's view, shines the background scene onto the back of the translucent screen, making it appear as if the actors are part of that environment. This technique was commonly used before the advent of green screen technology to create the illusion of being in a different location or setting.