VAE-Based 3D Image Restoration Method for PCB Profilometry

Abstract

This paper focuses on three-dimensional measurement system of printed circuit board components. Most automated optical inspections suffer from shadows and reflections obscured by the components. We propose a new method to restore shadow and reflection regions of components for accurate shape measurements, which defines shadow and reflection regions for restoration. The region is restored with a variational auto encoder-based restoration network. It is efficient to input information about both shadow and reflection region to restore the region. Additionally, long skip connection is added to VAE for improved accuracy. We confirmed its superiority through experiments by comparing its performance with other restoration networks such as cycle generative adversarial networks and coherent semantic attention inpainting.

Keywords

• 3D restoration
• deep learning
• moiré pattern profilometry (MPP)
• printed circuit board (PCB)
• variational auto encoder (VAE)