Imaging with blazed-binary diffractive elements

Blazed diffractive elements are currently fabricated with continuous profiles or with staircase approximations. Blazed-binary gratings are more recent diffiractive elements which implement continuous phase delays through a gradient-index artificial material with subwavelength binary etches. The performance of these diffractive elements in the resonance domain opens up new perspectives for manufacturing fast lenses. The objective of this paper is to review the main and unique properties of blazed-binary diffractive elements and to consider the consequences for monochromatic imaging systems.