Rear-projection video transmitting medium in balloon

A rear projection video communication media inside balloon is provided. A projector frame is hermetically mounted to a balloon. A projection screen is provided inside the balloon. A watchable transparent window is in front of the projection screen, and the projector frame is behind the projection screen. Ropes are provided between the projector frame and four corners of the projection screen for fixing, which provides assurance of distance and direction between the projector frame and the projection screen. A projector is equipped in the projector frame connecting with external circuit and various broadcast equipments through a lens projection signal, an electrical power cord and a signal line which are in front of the projector frame and extended out of the balloon. Light gas is supplied into the balloon when using to float in the air, and the balloon is fixed by stuffs like soft rope. The benefit of the utility model is that various applications is applicable, especially playing large screen video information in temporary ground. The rear projection video communication media inside balloon of the utility model has a simple structure which is easy to install and use.