Bandlimited illumination with engineered diffusers

Abstract

Engineered diffusers are refractive, achromatic optical elements with the capability to not only spread and homogenize an input beam but also shape the distribution of energy as well as intensity profiles. Bandlimited illumination is of particular interest for many applications that require certain intensity profiles over specific angular range with maximum efficiency. Here, we describe the concept and design of engineered diffusers as well as the method to fabricate them, from the initial resist master to volume production. Engineered diffusers are found to provide nearly ideal bandlimited illumination without image artifacts and with acceptable manufacturing tolerances.