Related Experiment Video
Updated: Aug 8, 2026
08:26
Cell Culture on Silicon Nitride Membranes and Cryopreparation for Synchrotron X-ray Fluorescence Nano-analysis
Published on: December 10, 2019
Millimeter-wave antireflection coating for cryogenic silicon lenses
Judy Lau1, Joseph Fowler, Tobias Marriage
1Department of Physics, Princeton University, New Jersey 08544, USA.
Applied Optics
|May 26, 2006
Summary
We developed a new antireflection coating for silicon lenses used in cosmic microwave background measurements. This Cirlex coating works at cryogenic temperatures, reducing reflection to less than 1.5%.
Area of Science:
- Optics and Materials Science
- Astrophysics and Cosmology
Background:
- Silicon lenses are crucial for sensitive instruments like those measuring the cosmic microwave background.
- Effective antireflection coatings are needed for optimal performance at cryogenic temperatures and specific wavelengths.
Purpose of the Study:
- To develop and test a novel antireflection (AR) coating for silicon lenses.
- To ensure the coating's efficacy and durability at cryogenic temperatures (4 K) for cosmic microwave background (CMB) measurements.
Main Methods:
- Developed an AR coating using machined Cirlex pieces bonded to silicon.
- Tested the coating's performance on flat silicon pieces and lenses.
- Subjected coated components to thermal cycling between 300 K and 4 K.
Main Results:
- Achieved reflection below 1.5% at the design wavelength for AR-coated silicon.
- The Cirlex coating demonstrated durability through multiple thermal cycles (300 K to 4 K).
- Successfully applied the coating to both flat optics and lenses.
Conclusions:
- The developed Cirlex AR coating is a viable solution for silicon optics in cryogenic, millimeter-wavelength applications.
- The coating exhibits excellent performance and robustness for demanding applications like CMB research.
- Further optimization can minimize optical loss in practical lens systems.
