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Title: Laminate polyethylene window development for large aperture millimeter receivers
New experiments that target the B-mode polarization signals in the Cosmic Microwave Background require more sensitivity, more detectors, and thus larger-aperture millimeter-wavelength telescopes, than previous experiments. These larger apertures require ever larger vacuum windows to house cryogenic optics. Scaling up conventional vacuum windows, such as those made of High Density Polyethylene (HDPE), require a corresponding increase in the thickness of the window material to handle the extra force from the atmospheric pressure. Thicker windows cause more transmission loss at ambient temperatures, increasing optical loading and decreasing sensitivity. We have developed the use of woven High Modulus Polyethylene (HMPE), a material 100 times stronger than HDPE, to manufacture stronger, thinner windows using a pressurized hot lamination process. We discuss the development of a specialty autoclave for generating thin laminate vacuum windows and the optical and mechanical characterization of full scale science grade windows, with the goal of developing a new window suitable for BICEP Array cryostats and for future CMB applications.  more » « less
Award ID(s):
1638957 2220446
PAR ID:
10433829
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ;
Editor(s):
Zmuidzinas, Jonas; Gao, Jian-Rong
Date Published:
Journal Name:
Millimeter, Submillimeter, and Far-Infrared Detectors and Instrumentation for Astronomy XI
Volume:
Proc. SPIE 12190
Issue:
Proc. SPIE 12190
Page Range / eLocation ID:
121902L
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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