Geometrical and physical optics analysis for mm-wavelength refractor telescopes designed to map the cosmic microwave background

Abstract

We present a compact two-lens HDPE f/1.6 refractor design that is capable of supporting a 28-deg diffraction-limited field of view at 1-mm wavelengths and contrast it to a similar two-lens refractor using silicon lenses. We compare the optical properties of these two systems as predicted by both geometrical and physical optics. The presented analysis suggests that by relaxing telecentricity requirements, a plastic two-lens refractor system can perform comparably to a similar silicon system across a wide field of view and wavelengths up to 1 mm. We show that for both telescope designs, cold stop spillover changes significantly across the field of view in a way that is somewhat inconsistent with Gaussian beam formalism and simple f-number scaling. We present results that highlight beam ellipticity dependence on both pixel location and pixel aperture size --- an effect that is challenging to reproduce in standard geometrical optics. We show that a silicon refractor design suffers from larger cross-polarization compared to the HDPE design. Our results address the limitations of solely relying on geometrical optics to assess relative performance of two optical systems. We discuss implications for future refractor designs.

arXiv comment15 pages, 17 figures

References in corpus (27)

• First M87 Event Horizon Telescope Results. I. The Shadow of the Supermassive Black Hole
• First Results from High Angular Resolution ALMA Observations Toward the HL Tau Region
• The South Pole Telescope
• The Atacama Cosmology Telescope: The polarization-sensitive ACTPol instrument
• ACTPol: A polarization-sensitive receiver for the Atacama Cosmology Telescope
• Optical Design of the Atacama Cosmology Telescope and the Millimeter Bolometric Array Camera
• CMB Polarization Systematics Due to Beam Asymmetry: Impact on Inflationary Science
• The Relative Performance of Filled and Feedhorn-Coupled Focal-plane Architectures
• BICEP Array: a multi-frequency degree-scale CMB polarimeter
• Large-aperture wide-bandwidth antireflection-coated silicon lenses for millimeter wavelengths
• Antenna-coupled TES bolometers used in BICEP2, Keck array, and SPIDER
• BICEP3: a 95 GHz refracting telescope for degree-scale CMB polarization
• Characterization of the BICEP Telescope for High-Precision Cosmic Microwave Background Polarimetry
• The Simons Observatory: Instrument Overview
• BICEP2/Keck Array IV: Optical Characterization and Performance of the BICEP2 and Keck Array Experiments
• The optical design of the six-meter CCAT-prime and Simons Observatory telescopes
• Window Function for Non-Circular Beam CMB Anisotropy Experiment
• Beam mismatch effects in Cosmic Microwave Background polarization measurements
• Ultra High Molecular Weight Polyethylene: optical features at millimeter wavelengths
• Design and performance of the Spider instrument
• Pre-flight integration and characterization of the SPIDER balloon-borne telescope
• ArtDeco: A beam deconvolution code for absolute CMB measurements
• The Cosmology Large Angular Scale Surveyor Receiver Design
• Optical modeling and polarization calibration for CMB measurements with ACTPol and Advanced ACTPol
• Full-sky beam convolution for cosmic microwave background applications
• PILOT: a balloon-borne experiment to measure the polarized FIR emission of dust grains in the interstellar medium
• Ray-tracing and physical-optics analysis of the aperture efficiency in a radio telescope

Cited by in corpus (2)

• The Simons Observatory: Modeling Optical Systematics in the Large Aperture Telescope
• Overview of the Medium and High Frequency Telescopes of the LiteBIRD satellite mission