Abstract: An optical projector arrangement includes a light source. Light from the light source is formed into a collimated beam travelling along an axis by optics. The light is split into red, green and blue components travelling in different paths by a splitter. The components are subsequently recombined by a synthesizer to continue along the axis to a projection lens. A respective liquid crystal modulator is included in each different path. In order to increase the optical length of the path taken by the green component so that it is equal to the lengths of the paths taken by the red and blue components, a path length compensator is included in the path for the green component, which path would otherwise be along the axis for the whole of its length.