Further guidance for broadband antireflection coating design.

Recent investigations have added to and refined the understanding of the behavior of broadband antireflection coating designs and provided further guidance for achieving more nearly optimal designs. The ability to optimize designs wherein the overall optical thickness of the design is constrained to a specific value has allowed this investigation. A broader bandwidth than previously reported has been studied and statistically fit more precisely by a polynomial equation, and also two linear equations for routine approximations have been derived. It has also been found that the optimal number of layers in the design can be predicted as a function of the bandwidth.