The hologram, a clear glass plate, is illuminated from a distance of less than a meter by a laser beam that has been diverged by scattering through a piece of wax paper. The laser beam strikes the hologram perpendicular to the plate. The proper view is seen by observing transmitted light at an angle on one side of the laser axis. However, if you view reflected light or look at the laser at a different angle (opposite the axis of the laser beam) the hologram appears backwards or upside down! Go figure that one out.