Case 14244

Method for Antireflection in Binary and Multi-Level Diffractive Optical Elements

Keywords:

Diffractive optical elements (DOE), antireflection, diffractive optics

Applications:

Can be used for any system that utilizes diffractive optics; like solar concentration, ablation, and lithography.

Problem:

Traditional DOE have both transmitted and reflected diffraction orders as a result of refractive index mismatch between the DOE’s material and the surrounding medium. When operating in transmission mode, a portion of the light is reflected at every dielectric-air interface resulting in a loss of energy of the transmitted field, severely impacting overall system performance.

Technology:

This invention describes a method for designing antireflective binary and multilevel DOE. A nanostructured antireflection layer is used to suppress undesirable reflections, thereby reducing system losses and increasing overall efficiency. The method consists of patterning subwavelength periodic nanostructures on top of the diffractive element.

Advantages:
  • Suppressed undesirable reflected orders
  • Significant increase of transmitted power
  • Reduces loss and improves system efficiency
  • Can be applied to all types of diffractive structures

Inventors:
  • Professor George Barbastathis (Department of Mechanical Engineering, MIT)
  • Chihhao Chang (Department of Mechanical Engineering, MIT)
  • Jose A. Dominguez-Caballero (Department of Mechanical Engineering, MIT)

Intellectual Property:

US Utility Patent Application 13/224472 filed 9/2/2011

Publications:

C.H. Chang, J.A. Domínguez-Caballero, H.J. Choi, and G. Barbastathis, “Nanostructured Gradient-Index Antireflection Diffractive Optics,” Optics Letters, Vol. 36, Issue 12, pp. 2354, 2011.

Last revised: February 21, 2012

»List of MIT Energy IP«