Astronomical instruments dedicated to the study of Cosmic Microwave Backgroundpolarization are in need of optics with very low systematic effects such as beam shapeand cross-polarization in an optical configuration. With the demand for millimetrewave larger focal planes comprising thousands of pixels, these systematic effects haveto be minimal across the whole focal surface. In order to reach the instrument requirementssuch as resolution, cross-polarization and beam ellipticity, new optical configurationswith well-understood components have to be studied. Refractive configurationsare of great importance amongst the potential candidates. The aim is to bring therequired technology to the same level of maturity that has been achieved with well-understoodexisting ones. This thesis is focused on the study of such optical componentsfor the W-band spectral domain. Using optical modelling with various softwarepackages, combined with the manufacture and accurate experimental characterizationof some prototype components, a better understanding of their performance has beenreached. To do so, several test set-ups have been developed. Thanks to these newresults, full Radio-Frequency refractive systems can be more reliably conceived.
|Date of Award||3 Jan 2014|
- The University of Manchester
|Supervisor||Bruno Maffei (Supervisor)|
- refractive optics
- millimeter wave lens
- CMB polarization instrumentation