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Showing 1 to 20 of 20 for “"diffractive optical elements"”.
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Integrated diffractive optical elements for terahertz beam shaping and polarization control /
… development, and optimization of integrated diffractive optical elements (DOEs) for efficient beam focusing, polarization control and enhanced transparency in the terahertz (THz) frequency range (0.1–1 THz). Utilizing semiconductor- and metal-based elements, the research introduces hybrid …
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Phase optimised general error diffusion for diffractive optical component design
Algorithms for developing Diffractive Optical Elements (DOEs) are improved to achieve real time holograms capable of switching at rates of 25frames/second or greater. A Phase Optimised General Error Diffusion (POGED) algorithm optimised for quality and speed of generation of diffractive elements is …
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All-Optically Addressed Spatial Light Modulator and Diffractive Optical Element Based on Photoalignment of Azobenzene Polymer
… (3D) displays hinges on the development of diffractive optical engines with high information bandwidth. However, conventional optical engines such as liquid crystal on silicon (LCOS) spatial light modulators (SLMs) and optically addressed SLMs (OASLMs) face scalability limitations in …
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Alignment and actuation of compliant nanostructures and diffractive optics by inter-nanomagnet forces
… work shows the ability of nanomagnets to tune diffractive optical elements through deformation and actuation of nanostructured freestanding beams such as in a diffraction grating. This actuation combines the advantages of both analog and digital tuning techniques. For both applications, …
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Maskless nanolithography and imaging with diffractive optical arrays
… the ZPAL system, from the micromechanics, to the diffractive optics, to the control system. Special emphasis is placed on the design, fabrication and characterization of high-numerical-aperture diffractive optical elements for lithography and imaging. The results achieved provide conclusive …
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Novel quantum dot and nano-entity photonic structures
… as active waveguides, micro-ring structures and diffractive optical elements for sensing applications. Design, synthesis and characterization of nanocomposite materials in this context, involves QD incorporation in tailored-made polymers, synthesized using radical polymerization as well as QD …
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Optical Printing of Multiscale Hydrogel Structures
… a chip and biophotonics applications. A range of optical fabrication technologies such as photolithography, digital projection stereolithography and laser direct writing have been used to shape hydrogels into structurally complex functional devices and constructs. However, it is still greatly …
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Design and fabrication of novel and functional 3D structures via proximity field nano-patterning
… more common bilevel gratings that are used as diffractive optical elements (DOE) for PnP. This move results in a significantly expanded 3D structure motif design space that can be exploited with the genetic algorithm based inverse design approach. Finally, PnP is used to demonstrate the …
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Diffractive optical lens design and fabrication for integrated monitoring of microelectromechanical lateral comb resonators
… is gathered from these devices during operation. Optical monitoring has been shown by various groups to be capable of achieving this goal. However, Integrated Optical Monitoring (IOM) must be achieved in order to enable incorporation with the MEMS die in a single package for effective lifetime …
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Propagation Effect In Inhomogeneous Media, Including Media With Light-induced And Fixed Gratings
Optical waves propagation in various types of volume gratings, materials with constant impendence and optical fibers are studied. Instability of cross–phase modulation and of Energy transfer via GRON-type (Grating-type Orientational Nonlinearity in Liquid Crystal) Stimulated Scattering is …
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Computational Modelling and Experimental Verifcation of Quasioptical Components at Millimetre Wavelengths
… various analysis techniques used in the optical characterisation of millimetre wave radiation. The results presented relate to both computational simulation and experimental measurements carried out at NUI Maynooth. The majority of the analysis is centred around a frequency of 100 GHz, or …
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Modification and processing of glass and glass with embedded silver nanoparticles
… describes three methods of manipulating the optical and structural properties of glass and nanocomposite glass for varying applications. These are: thermal poling of glass, electric field assisted dissolution of glass embedded with silver nanoparticles and the irradiation of glass embedded …
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Performance and Analysis of a Deployable Diffractive Optical Element for Small Satellite Missions
… lighter, and more deployable instrumentation, diffractive optical elements (DOEs) offer a compelling alternative to traditional optics. Their ability to focus light through engineered phase profiles rather than curved surfaces allows for large-aperture, flat optics that are far lighter and …
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Disordered Optics for Multidimensional Information Processing
… The first part of the thesis is about diffractive optical elements (DOE) for spectral imaging. We designed a spatially modulated DOE filter that can efficiently sample in the Fourier transformed domain and facilitate spectral image reconstruction. The DOE layer distinguishes the main …
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The Design and Optimisation of Quasioptical Telescopes
… increased in these systems, and also to design Diffractive Optical Elements (DOEs) for use at terahertz and submillimetre wavelengths in general. The standard methods of the Gerchberg-Saxton Algorithm, and unidirectional optimisation using Differential Evolution and Simulated Annealing are …
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Fast Multilevel Algorithms for the Electromagnetic Analysis of Quasi-Planar Structures
… planar microwave circuits, microstrip arrays, diffractive optical elements, and solar cells. The prediction of electromagnetic radiation and scattering is essential in applications involving the structures listed above. Possibly the most widespread class of techniques for this purpose is based …
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New approaches for optical and microoptical diagnostics in IC engines
… in-situ diagnostics methods. Hence, laser-based optical diagnostics are essential for internal combustion (IC) engine research. Within this work, microoptical systems that enable the ap-plication of optical diagnostics methods on unmodified production-line engines or engines with micro-invasive …
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Realization of a 3D gradient index medium in porous silicon
… of photonic and gradient refractive index (GRIN) optical elements. After a porosity-dependent index profile is etched into the PSi element, the optical response can be further modified by introducing secondary materials into the void volume of the mesoporous structure, thereby changing the filled …
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Additive Lithography Fabrication And Integration Of Micro Optics
Optical elements are the fundamental components in photonic systems and are used to transform an input optical beam into a desired beam profile or to couple the input beam into waveguides, fibers, or other optical systems or devices. Macroscopic optical elements are easily fabricated using grinding …