5. Achromatic Diffractive Optical Elements (DOEs) for Broadband Applications

The integration of diffractive optical elements (DOEs) into a broadband optical system can often allow for increasing the system’s performance, reducing its size, or its complexity. However, despite considerable efforts to develop different technologies for DOEs, they still remain highly underutilized in broadband imaging system. This is because DOEs that maintain high diffraction efficiencies across the full range of wavelengths, angles of incidence (AOIs), and grating periods required for different optical systems are currently not available. Since the wavelength dependence of the efficiency is fundamentally linked to the dispersion of the phase delay \((\phi (\lambda )\)), this leads to the question of whether the dispersion engineering capabilities of nanocomposites could make such materials an enabling technology for finally unlocking the full potential of DOEs for optical design. In this chapter, I address this question as my first advanced application for nanocomposites. At the same time, my second goal in this chapter is to not restrict myself to one material platform and embodiment of DOEs, but also develop general concepts for how DOEs for broadband systems can be designed.