There is provided a holographic projection system arranged to project light to a rectangular replay field. The holographic projection system comprises: a spatial light modulator, comprising an array of pixels, arranged to receive a computer-generated hologram and output spatially-modulated light forming a holographic reconstruction at the rectangular replay field, wherein each pixel is rectangular; and a light source arranged to illuminate the plurality of pixels to form the spatially-modulated light forming a holographic reconstruction at the replay field, wherein the rectangular replay field is spatially separated from the spatial light modulator and the aspect ratio of the rectangular replay field is substantially equal to the aspect ratio of each pixel but orthogonally orientated.