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Abstract

Computer-generated holography, a technique for synthesizing holographic images using computer algorithms, has advanced with developments in computational methods and digital technologies. However, the traditional methods struggle to achieve computational speed and accuracy, simultaneously. To address this, this dissertation explores the integration of deep neural networks with semi-analytical methods to enhance the hologram design and its performance across various applications. We develop solvers based on physics-informed neural networks to enable phase optimization and mitigate errors due to due to system noise and imperfections. In the first project, a novel layer-based holography approach combines deep Convolutional Neural Networks (CNNs) with a Bessel beam expansion known as Frozen Waves (FWs) to generate images on longitudinal planes, perpendicular to holographic displays. Two distinct solvers are developed: one based on analytical simulations for scalability, and another using numerical Angular Spectrum Method (ASM) for enhanced flexibility and accuracy. Additionally, a Look up Table (LuT) method was developed to accelerate the numerical simulations. The second project provides an alternative method by combining neural networks with a Plane Wave (PW) expansion. This hybrid system exhibits improved accuracy and computational efficiency compared to the previous method utilizing FWs. Experimental data demonstrates the effectiveness of this method in practical holographic setups. In the third project, our framework was applied to Orbital Angular Momentum (OAM)-multiplexed holography in the spatial frequency domain. This system achieves higher multiplexing capacity and lower error levels as compared to previously proposed methods, notable using phase-only holograms. Furthermore, a realistic, parameterized propagation model of a Fourier domain holography system was developed using a Camera-In-The-Loop (CITL) approach. This model, which captures non-idealities and noise models, was incorporated in the hologram design pipelines to improve image quality in real-world settings. Ultimately, this research contributes to computer-generated holography by showcasing new applications of machine learning to enhance traditional methods. The proposed techniques offer improvements in image quality and computational speed, suitable for real-time applications in areas such as augmented reality, imaging and optical communication systems.

Details

1010268
Title
Layered and Orbital Angular Momentum Multiplexed Holography Using Deep Learning
Number of pages
140
Publication year
2025
Degree date
2025
School code
0779
Source
DAI-B 87/5(E), Dissertation Abstracts International
ISBN
9798265440785
Advisor
Committee member
Aitchison, Stewart J.; Helmy, Amr S.
University/institution
University of Toronto (Canada)
Department
Electrical and Computer Engineering
University location
Canada -- Ontario, CA
Degree
Ph.D.
Source type
Dissertation or Thesis
Language
English
Document type
Dissertation/Thesis
Dissertation/thesis number
32168716
ProQuest document ID
3276195143
Document URL
https://www.proquest.com/dissertations-theses/layered-orbital-angular-momentum-multiplexed/docview/3276195143/se-2?accountid=208611
Copyright
Database copyright ProQuest LLC; ProQuest does not claim copyright in the individual underlying works.
Database
ProQuest One Academic