A projection system is disclosed, the projection system including: an illumination unit; a PBS (Polarizing Beam Splitter) reflecting the light from the illumination unit, transmitting an image light, having a width larger than that of entrance pupil through which the image light is incident, and having a structure in which a width of an area facing projection lenses is larger than that of an area perpendicular to an area facing the projection lenses; a display device receiving the light reflected from the PBS and outputting the light as an image light; and a projection unit mounted with the projection lenses for projecting the image light outputted from the display device to a screen.