An Analysis of Arrays with Irregular Apertures in MEMS Smart Glasses for the Improvement of Clear View

Abstract

An innovative glass substrate surface technology including integrated micro-electro-mechanical systems (MEMS) is presented as an advanced light modulation, heat control, and energy management system. This smart technology is based on millions of metallic micromirrors per square meter fabricated on the glass surface, which are arranged in arrays and electrostatically actuated. The smart window application exploits an elaborate MEMS glass technology for active daylight steering and energy management in buildings, enabling energy saving, CO2 emission reduction, a positive health impact, and improved well-being. When light interacts with a glass substrate that has regular, repetitive patterning at the microscopic scale on its surface, these microstructures can cause the diffraction of the transmitted light, resulting in the potential deterioration of the view quality through the smart glass. A reduction in optical artifacts for improved clear view is presented by using irregular geometric micromirror apertures. Several non-periodic, irregular micromirror aperture designs are compared with corresponding periodic regular designs. For each considered aperture geometry, the irregular array reveals a reduction in optical artifacts and, therefore, by far a clearer view than the corresponding regular array. A systematic and comprehensive study was conducted through design, simulation, technological fabrication, experimental characterization, and analysis.

Keywords

• micromirror arrays
• smart glass
• improved clear view
• irregular apertures
• light modulation
• energy saving