3-D optical microscopy with a new synthetic SFF algorithm to reconstruct surfaces with various specular and diffusive reflectance
Journal
International Journal of Advanced Manufacturing Technology
Date Issued
2023-01-01
Author(s)
Chen, Yu Sheng
Abstract
An optical measuring method that leverages a new synthetic shape-from-focus (SFF) algorithm is proposed for reconstructing microstructure surfaces. This method represents a major advance in optical measurement capabilities as it can capture both specular and diffusive characteristics within a single field of view, something that cannot be achieved by other existing methods. To enhance measurement precision, a microscopic optical design has been proposed that uses digitally controlled structured patterns on hybrid reflective surfaces. The novel synthetic SFF algorithm increases measurement precision and accuracy. Industrial parts were evaluated using a pre-calibrated optical instrument, and the results showed that the measured precision of 3-D full-field surface profilometry can reach a microscale level, leading to improved microscopic object reconstruction with an improvement of up to 80% in precision and accuracy. This technique is ideal for use in automated optical inspection (AOI), a crucial requirement for many modern in-line manufacturing processes.
Subjects
Automated optical inspection (AOI) | Digital micromirror device (DMD) | Optical microscopy | Shape from focus (SFF) | Surface reflectivity
SDGs
Type
journal article