Simultaneous Imaging and Precision Alignment of Two mm Wave Antennas Based on Polarization-Selective Machine-Vision

In this paper, we present an optical imaging tool, the Overlay Imaging Aligner (OIA), developed to aid in the mechanical alignment of antenna components in the mm-wave and low-THz frequency regimes (50-500 GHz) where the millimeter and sub millimeter wavelengths pose significant alignment challenges. The OIA uses a polarization-selective machine-vision approach to generate two simultaneous and overlaid real-time digital images along a common axis; this allows for aligning two antenna components to within fractions of a wavelength in the mm-wave and THz frequency regimes. The overall concept, optical design, function, performance characteristics and application examples are presented. A quantitative assessment of the alignment accuracy achievable with the OIA at specific frequencies in the WR-2.2 band is made where the alignment achieved with the OIA is compared to an electrical alignment.