Optimization of multilayer stack for reflection

A graphical user interface was developed, allowing researchers and engineers to find thicknesses as to optimize the reflectivity of a multilayer stack, dependent on wavelength, materials and angle of incidence. Unlike previous research, the code allows for full freedom in possible thicknesses. Despite this, however, alternating thicknesses seem to give the best results, for alternating materials. This is true with possible exceptions for the first and last layer. With 30 layers of alternating glass (SiO2) and titanium dioxide (TiO2), using thicknesses of 129nm and 65nm an average reflection coefficient (averaged over the angular spectrum) of 0.999983 was found for light with a wavelength of 632.8nm - light produced by a HeNe laser. Upon changing the first and last layer’s thickness to 168nm this average reflection coefficient increased to 0.999989.Optics Research GroupImaging PhysicsApplied Science