Abstract: A backlighting arrangement is for a head up display that presents a virtual image to a human driver of a motor vehicle. The arrangement includes a light source emitting light with a non-uniform brightness over a field of view of the human driver. A diffuser includes a surface through which the light emitted by the light source passes. The surface has a texture that varies with position on the surface. The texture scatters the light such that the brightness of the light over a field of view of the human driver is more uniform after passing through the diffuser at a given average brightness than it would be with a diffuser configured to scatter light independent of position after passing through the diffuser.