SBIR Phase I: Hybrid Fabrication of Very High Efficiency Gratings

Diffraction Ltd, Waitsfield VT

Investigators

Abstract

This Small Business Innovation Research (SBIR) Phase I project proposes to address the need for large highly efficient gratings as essential components of astronomical, spectroscopic, and optical telecommunications equipment. The goal of the proposed research program is to develop a hybrid manufacturing process combining holography and preferential chemical etching to produce large area diffraction gratings on both planar and curved surfaces that exhibit higher efficiency than gratings manufactured with current techniques. These gratings can be used as dispersing elements and optical filters in astronomical instruments, as extremely narrow band pass filters in pump lasers for optical telecommunications, and as multiplexers and de-multiplexers for wavelength division multiplexing (WDM) equipment. Of particular significance will be the ability to produce large area efficient gratings on concave surfaces. This will allow dispersion and focusing functions to combine within the same optical element on space-based telescopes. Diffraction gratings produced using current generation techniques such as ruling engines, holography, and E-beam mask writers can be improved upon greatly in terms of efficiency, cost, and material performance (such as thermal and chemical stability). Highly efficient, large area, planar or curved, diffractive structures made of non out-gassing materials are of great interest to institutions and companies in the fields of astronomy, spectroscopy, laser manufacture, and optical telecommunications.