This invention relates to optical splitters, particularly to optical splitters for use in optical touch screens. The present invention provides an optical splitter for distributing light substantially equally from a multimode input waveguide to an array of output waveguides, via a slab region. The distribution of output waveguide widths is chosen to complement the intensity distribution in the slab region, which may or may not be substantially uniform. The invention also provides an optical splitter for distributing light substantially equally from an optical source to a plurality of waveguides, wherein said optical source directs a beam of light into a slab region. The distribution of waveguide widths is chosen to complement the intensity distribution in the slab region, which may or may not be substantially uniform. When used to distribute optical power in optical touch screens, the splitters of the present invention may be used in series and/or in parallel.