frame 104 can be made from a number of different tube sizes at least one embodiment uses tubing having a profile of 32 mm u00d7 32 mm square in cross section in certain embodiments this tubing is extruded aluminum alloy with a weight of 0 6 kg m the 32 mm u00d7 32 mm profile tubing has been found suitable for all screen sizes up to at least 400 u00d7 400 cm 600 u00d7 300 cm or 900 u00d7 300 cm in another embodiment the frame 104 is constructed of tubing having a cross section of 64 u00d7 32 mm this tubing has been used successfully in frames as large as 500 u00d7 340 cm and up this size of tubing can also of course be used in smaller frames if the application requires additional strength or rigidity as explained in more detail below applicants have developed a novel way to integrate the corner braces of the frame 104 into the interior of the frame 104 rather than attaching it externally as found in the prior art this innovation has proved to be a significant enhancement to the overall performance of the device this feature also facilitates the use of a folding projection surface 102 with square corners this further enhances the performance of the device a second innovation of the present invention is the incorporation of pressure release push button self latching inline hinges.