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Embossed holographic elements, such as diffraction gratings, display holograms and optical discs are now firmly established as mass-replicated items. The embossed hologram has evolved from its original form recorded in emulsion on glass plate to present-day images stamped into plastic. The process of obtaining a holographic image in plastic requires several stages of information transfer: first a surface relief image must be recorded into emulsion; next a metal replica must be made; finally the embossed plastic image is produced. A detailed analysis of the information transfer process has been undertaken and is described.

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Electron microscopes offer scientists an invaluable tool in probing matter at a very small scale. Rapid advancements over the past several decades has allowed electron microscopes to routinely image samples at the atomic scale. These advancements have been in all aspects of electron microscope design – such as more stable control voltages and currents, brighter and more coherent sources, beam aberration correction, and direct electron detectors, to name a few. One very recent advancement is in shaping the electron beam to provide an almost arbitrary set of possible beam profiles. Following the demonstration of electron vortex beams in 2010, there has been a surge of interest in the potential shaping electron beams. Utilizing holographic electron diffraction gratings, an almost arbitrary set of electron beams can be generated. These diffraction gratings are challenging to create due their tiny size and the precision with which they must be fabricated. We present a comprehensive study on the fabrication and design of electron diffraction gratings with the aim of being able to produce optimal gratings that result in bright, well separated beams which closely match a desired beam profile. We have developed and optimized fabrication of these gratings with focused ion beam milling, and have been able to use the fabricated gratings in a number of important experiments. These electron diffraction gratings have allowed us to perform various experiments such as aberration correction, electron helical dichroism, advanced phase-contrast imaging, and multi-beam interferometric techniques. Holographic beam shaping will continue to be an important tool for electron microscopists.

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Most of the time, in a nano-fabrication facility, the efforts of a researcher are devoted to optimising the fabrication process in order to avoid defects and obtain the best result in terms of precision and quality of the fabricated device. However, it is inevitable that during the sample fabrication, a variable intrinsic amount of disorder is introduced. This feature can be exploited to develop novel applications spanning different areas of optics. A perfect unclonable cryptographic system based on new integrated optical fingerprints chip is presented and a proof of concept is provided. The role of disorder at the nanoscale is further studied in the fabrication processes such as electron beam lithography and dry-etching. In this scenario, the randomness is the starting point to develop new technologies for structural coloration and holograms.

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The necessity to align a multi component null corrector that is used to test the 8.4 [m] off axis parabola segments of the primary mirror of the Giant Magellan Telescope (GMT) initiated this work. Computer Generated Holograms (CGHs) are often a component of these null correctors and their capability to have multiplefunctionality allows them not only to contribute to the measurement wavefront but also support the alignment. The CGH can also be used as an external tool to support the alignment of complex optical systems, although, for the applications shown in this work, the CGH is always a component of the optical system. In general CGHs change the shape of the illuminating wavefront that then can produce optical references. The uncertainty of position of those references not only depends on the uncertainty of position of the CGH with respect to the illuminating wavefront but also on the uncertainty on the shape of the illuminating wavefront. A complete analysis of the uncertainty on the position of the projected references therefore includes the illuminating optical system, that is typically an interferometer. This work provides the relationships needed to calculate the combined propagation of uncertainties on the projected optical references. This includes a geometrical optical description how light carries information of position and how diffraction may alter it. Any optical reference must be transferred to a mechanically tangible quantity for the alignment. The process to obtain the position of spheres relative to the CGH pattern where, the spheres are attached to the CGH, is provided and applied to the GMT null corrector. Knowing the location of the spheres relative to the CGH pattern is equivalent to know the location of the spheres with respect to the wavefront the pattern generates. This work provides various tools for the design and analysis to use CGHs for optical alignment including the statistical foundation that goes with it.

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