We will present recent advances in Kaleido Technology on the
ultra-precision diamond-milling process, which is an
extremely versatile tool for manufacturing of masters for wafer-based replication technologies. Diamond-milling has the
advantage of being able to manufacture lenses with much larger radii of curvatures compared to etching methods.
Spherical-, aspherical- and free-form-surfaces have been machined with form accuracies better than 200 nm (PV), arrays
up to 50 x 50 mm have been manufactured on wafers, with lens-position accuracies better than 3 μm absolute over the
A Two-dimensional holographic memory for archival storage is described. Assuming a coherent transfer function, an A4 page can be stored at high resolution in an area of 1 mm<SUP>2</SUP>. Recently developed side-chain liquid crystalline azobenzene polyesters are found to be suitable media for holographic storage. They exhibit high resolution, high diffraction efficiency, have long storage life, are fully erasable and are mechanically stable.
We describe novel organic compounds based on polyester and peptide backbones with azobenzenes in the side chain for erasable holographic storage. These materials exhibit high diffraction efficiency, high resolution and long storage life and can be used for holographic storage in a broad spectra window of 415 - 530 nm. In polyester thin film systems with a chiral azobenzene, diffraction efficiencies of about 50% have been achieved with just 300 ms exposure. Through atomic force and near-field optical microscopic investigations, we have found an aggregation process encompassing both the main and side chains to be responsible for the permanent storage in the case of polyesters. The stored information can be erased globally in this case with heat. On the contrary, holograms written in peptide films are not totally erased even after exposure to 250 degree(s)C for one month. However, the information can be locally erased using circularly polarized light. A strong polarization dependent surface relief is observed both for the polyesters and peptides. Through FTIR and surface profile measurements, we further show that irradiation of the films with p- polarized light results in a large surface roughness. We show that in the case of the polyesters the storage is mostly due to optical anisotropy and in the case of the peptide oligomers, both the anisotropy and surface relief are large.