Aluno: Alex Reimann Cunha Lima
Orientador: Prof. Dr. Manuel Menezes de Oliveira Neto
Título: Simulating Accommodation and Low-Order Aberrations of the Human Eye using Wave Optics and Light-Gathering Trees
Linha de Pesquisa: Computação Gráfica e Visualização de Dados
Local: Prédio 43412 – Sala 215 (sala de videoconferência) – Instituto de Informática UFRGS
Prof. Dr. Daniel Gerardo Aliaga (Purdue University – por videoconferência)
Prof. Dr. Marcelo Walter (UFRGS)
Prof. Dr. Martin Cadik (BUT – Brno University of Technology – por videoconferência)
Presidente da Banca: Prof. Dr. Manuel Menezes de Oliveira Neto
Abstract: In this work, we present two practical solutions for simulating accommodation and low-order aberrations of optical systems, such as the human eye. Taking into account pupil size (aperture) and accommodation (focal distance), our approaches model the corresponding point spread function and produce realistic depth-dependent simulations of low-order visual aberrations (e.g., myopia, hyperopia, and astigmatism). In the first solution, we use wave optics to extend the notion of Depth Point Spread Function, which originally relies on ray tracing, to perform the generation of point spread functions using Fourier optics. In the other technique, we use geometric optics to build a light-gathering tree data structure, presenting a solution to the problem of artifacts caused by absence of occluded pixels in the input discretized depth images. As such, the resulting images show seamless transitions among elements at different scene depths. We demonstrate the effectiveness of our approaches through a series of quantitative and qualitative experiments on images with depth obtained from real environments. Our results achieved SSIM values above 0.94 and PSNR above 32.0 in all objective evaluations, indicating strong agreement with the ground-truth.
Keywords: Visual simulation. low-order aberrations. partial occlusion artifacts. Fourier Optics. Zernike polynomials.