which an observer can see the image 11 from the outside with sufficient brightness and contrast even during daylight conditions without the internal space 5 designed as a dark space such a projection during daylight conditions would be virtually impossible this is the most serious disadvantage of the two dimensional screens of the prior art explained at the beginning furthermore the particularly preferred embodiment described here of the large sized transportable projection screen ensures stability and mobility to a particularly improved extent owing to the structure 1 of an inflatable tubular frame which structure is formed by tubes 3 3 a the tubes have a comparatively large tube diameter in the range of 1 5 m a special fan blower shown in fig5 to 11 ensures a simple and sufficiently stable construction of the structure 1 which as a result has sufficient intrinsic stability even during adverse weather conditions the main characteristic of the large sized projection screen which is illustrated perspectively in fig3 and fig4 lies in the projection of transmissions however film and advertising presentations can likewise also be shown furthermore the side surfaces and the back wall are designed for the attachment of advertising prints for this purpose the structure 1 has inter alia eyelet strips 14.