Epiderm SAS

When building spot array binary Fourier diffractive optical elements (DOEs) having feature sizes on the order of the wavelength, we noticed remarkable variations in the experimental diffraction efficiency compared to the simulation results. Even with the use of high-cost electron beam lithography and rigorous Fourier modal method simulations, there appear to be no publications, to the best of our knowledge, showing close agreement in diffraction efficiency between the simulation and experimental results. In this Letter, we show that the diffraction symmetry of binary Fourier DOEs can be an efficient and consistent metric for evaluating the limit of the thin-element approximation and the effects of fabrication errors.

We present a method that makes it possible to deposit and bond micro-elements on an underlying device.In this manner, micro-constructions can be built by the addition of micro-bricks.The elements are fabricated on a flexible substrate covered with a release coating and are subsequently transferred and bonded onto the target device in a collective process.The process works on complex geometries and can accommodate surface defects, while maintaining a tightly controlled geometry.Application to the fabrication of liquid crystal micro-cells is presented.

A photoplotter, based on a digital micromirror device as real-time reconfigurable mask, is designed to direct-write microstructures in different photosensitive materials.Binary and multilevel elements, such as computer generated holograms with 2, 4, and 8 phase levels and planar optical waveguide structures with tapers and/or long period gratings, are fabricated in a single processing step.Direct parallel write into different photosensitive materials with attractive optical properties is proposed and first results are shown in a com. available organic-inorganic hybrid material.