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 (30, 50, 70) having a first side (32, 52, 72) is worked to form a diffuser surface relief structure (33, 53, 73) thereon. The substrate can be buffed using a buffing agent (34) 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 (80) 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.