Design and analysis of multi-wavelength diffractive optics

Department of Electrical and Computer Engineering, University of Utah, Salt Lake City, Utah 84112, USA.
Optics Express (Impact Factor: 3.49). 01/2012; 20(3):2814-23. DOI: 10.1364/OE.20.002814
Source: PubMed


We present an extension of the direct-binary-search algorithm for designing high-efficiency multi-wavelength diffractive optics that reconstruct in the Fresnel domain. A fast computation method for solving the optimization problem is proposed. Examples of three-wavelength diffractive optics with over 90% diffraction efficiency are presented. These diffractive optical elements reconstruct three distinct image patterns when probed using the design wavelengths. Detailed parametric and sensitivity studies are conducted, which provide insight into the diffractive optic's performance when subject to different design conditions as well as common systematic and fabrication errors.

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    • "Spectrum splitting holographic elements, which are fabricated by recording an interference pattern on a holographic medium, represent a relatively cheap solution for spectral splitting applications [14] [15] [16], but suffer from low optical efficiencies due to noise or undesired interference effects [13]. Thin diffractive-optical elements, which are characterized by a micro-structured surface, have been used for spectrum splitting applications [17] [18] [19] [20] because of their versatility, which allows the achievement of different spectral combinations. Nevertheless, their high cost and complexity have limited their use. "
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