A diffuser master is provided which is manufactured mechanically instead of
holographically. The master can be made from a suitable substrate
including relatively hard materials such as plastic, glass or metal. A
substrate having a first side is worked to form a diffuser surface relief
structure thereon. The substrate can be buffed using a buffing agent of a
selected grit in order to form surface scratches in the first side of the
substrate. The substrate can also be blasted with shot particles in order
to form indentations and depressions in the first side. The substrate can
alternatively be acid or alkali etched in order to form surface
irregularities in the first side. The scratches, depressions or
irregularities can be formed in order to create a desired surface relief
and hence desired diffuser output characteristics.