Dissertation Title:
“Holographic optical elements for visible light applications in photo-thermo-refractive glass”
Abstract:
This dissertation reports on design and fabrication of various optical elements in Photo-thermo-refractive (PTR) glass. An ability to produce complex holographic optical elements (HOEs) for the visible spectral region appears very beneficial for variety of applications, however, it is limited due to photosensitivity of the glass confined within the UV region. First two parts of this dissertation present two independent approaches to the problem of holographic recording using visible radiation. The first method involves modification of the original PTR glass rendering it photosensitive to radiation in the visible spectral region and, thus, making possible the recording of holograms in PTR glass with visible radiation. The mechanism of photoionization in this case is based on an excited state absorption upconversion process in the glass when doped with Tb3+. By contrast, the second approach uses the original Ce3+ doped PTR glass and introduces a new modified technique for hologram formation that allows for holographic recording with visible light. Complex HOEs including holographic lenses and holographic curved mirrors were fabricated in PTR glass with visible light using both techniques. Those optical elements can be useful for applications such as LIDAR, virtual and augmented reality, free space optical communication etc.
The third part of the dissertation takes a step in a different direction and discusses the development of the methods for fabrication of phase masks in PTR glass. A method for relatively straightforward and inexpensive fabrication of phase masks with the aid of a Digital Micromirror Device is presented. This method enabled to produce phase masks containing complex greyscale phase distributions for generation of vortex (helical) beams. A phase mask can be holographically encoded into a transmission Bragg grating where a holographic phase mask (HPM) is formed. HPM has an advantage over a regular phase mask of being capable of multi-wavelength operation. Besides, several HPMs can be multiplexed inside a single PTR glass plate making it possible that one optical element can be used for the generation of several beam shapes. A multiplexed HPM operating as a coherent beam splitter and simultaneous generator of vortex beams was presented. All optical elements recorded in PTR glass preserve the advantages peculiar to VBGs recorded in PTR glass such as stability to heating and illumination with high-power laser beams..
Major: Optics and Photonics
Educational Career:
BS: 2012, Technical Physics, Peter the Great St. Petersburg Polytechnic University
MS: 2017, Optics and Photonics, University of Central Florida
Committee in Charge:
Dr. Leonid Glebov (Chair)
Dr. Kathleen Richardson
Dr. Axel Schülzgen
Dr. Talat Rahman
Approved for distribution by Dr. Leonid Glebov, Committee Chair, on April 16, 2019.
The public is welcome to attend.
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