Stacks of optical structures and methods and apparatus for making same

摘要

Stacked optical structures and methods and apparatus for making them are provided. The stack has a uniform gap between adjacent structures in which (1) a mixture of adhesive and mechanical spacers and (2) an optical filler, or adhesive, is placed. Each stacked optical structure includes at least two optical substructures, each of which has a mating surface. The thickness of the gap is equal to the maximum diameter of the mechanical spacers. The mixture is distributed in the gap away from an optical axis and the optical filler is distributed in the gap such that the optical axis passes through it.