The invention relates to a device for projecting an image on a surface, comprising: a light source generating a light beam; a mask arranged in the path of the light beam; a lens arranged behind the mask to focus the image of the mask on a surface, wherein the surface is not parallel to the lens, wherein at substantially each position along the edges of the mask the distance v to the lens and the distance b of the corresponding position at the edges of the image of the mask to the lens correspond substantially to the formula 1/v+1/b=1/f, wherein f is the focal length of the lengths. The invention also relates to a device for moving the image on the surface.