Patent ID: 8270075

Claim:
A projection apparatus, comprising: a support frame defining a projection area; a polymeric screen of sheet material sized and shaped to span at least a portion of the projection area; a retention member operative to contact the polymeric screen along an edge thereof; and a tensioning assembly operative to apply tension to the screen via the retention member, the tensioning assembly being operative to selectively reposition the retention member relative to the support frame; wherein: the tensioning assembly comprises a pressure source and a piston, the pressure source being operative to selectively apply pressure to the piston such that movement of the piston repositions the retention member relative to the support frame; the pressure source is a pressurized air source; the retention member is a first retention member and the piston is a first piston; the apparatus further comprises a second retention member operative to contact the polymeric screen; and the tensioning assembly further comprises a manifold and a second piston, the manifold communicating with the pressure source and being operative to distribute pressure to the first retention member and the second retention member such that movement of the first piston repositions the first retention member and movement of the second piston repositions the second retention member.