Viewing point perpendicular to the screen

Projector

At correct perpendicular viewing point the blinds disappear and the image is seen

Cylindrical wall preventing non-perpendicular projections

Blinds

Viewing point perpendicular to the screen

Projector

Screen with blinds preventing a viewer from seeing the image from a non-perpendicular viewpoint.  A lenticular lens may be substituted for the blinds.

 A full-size cylindrical wall may be substituted for the blinds or lenticular lens as a means of preventing non-perpendicular viewing.

Blinds

Projector

Projector

Viewing point

Viewing point

Viewing point

Viewing point

Viewing point

Viewing point

Alternate screen with four sides and viewing points

Projector

Projector

Display Surface

Display Surface

Display Surface

Display Surface

Pojected Image

Pojected Image