ViewSonic Projector summarizes the projector’s basic and advanced know-how to end users, installers, or distributors. It contains a bunch of practical information for choosing appropriate projectors in different scenarios. No matter small meeting room, middle classroom, or big hall, ViewSonic Projector tells you how far the projector should be placed according to the room ceiling height, projector’s screen size, aspect ratio, etc. Just input several figures, the result will be displayed in the s