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In this paper, we adopt the coded aperture technique to the alignment process for industrial machinery. As a special setting for assembly and inspection, such machinery uses an illumination of narrow wavelength range for imaging with less aberration. This leads to significant influence of light diffraction on the image restoration. Although the diffraction was treated as negligible in most previous studies of coded aperture since they were carried out for natural images, the aperture patterns of them do not achieve enough accuracy for the alignment. We optimize the aperture pattern by performing a simulation of light diffraction, and we experimentally show that it achieves better performance in the alignment. [ABSTRACT FROM PUBLISHER]

This paper proposes a new system for the unsupervised diagnostic and monitoring of defects in waveguide imaging. The proposed method is automatic and does not require manual selection of specific frequencies for defect diagnostics. The core of the method is a computational intelligent machine learning algorithm based on sparse non-negative matrix factorization. An internal functionality is built into the machine learning algorithm to adaptively learn and control the sparsity of the factorization, and to render better accuracy in detecting defects. This is achieved by using Bayesian statistics methodology. The proposed method is demonstrated on automatic detection of defect in metals. In addition, we show that the extraction of the spectrum signature corresponding to the defect is significantly more efficient with the proposed optimal sparsity, which subsequently led to better detection performance. Experimental tests and comparisons with other sparse factorization methods have been conducted to verify the efficacy of the proposed method. [ABSTRACT FROM PUBLISHER]

A new approach for designing the binary phase-only hologram with arbitrary-shaped polygonal apertures is proposed. The diffraction of the aperture was computed with the analytical Abbe transform. To explore the very high number of degrees of freedom available in the computer-generated hologram (CGH) of very large pixel count, a two-step optimization including the genetic algorithm with local search for encoding binary phases of apertures followed by the direct search for floating covertices of the elementary triangular apertures was developed for high performance and low image-reconstruction error of the binary CGH. [ABSTRACT FROM PUBLISHER]