Simons Observatory (SO) is a large-scale international experimental project utilizing multiple ground-based telescopes installed in South America, Chile.
Through precise observations of the Cosmic Microwave Background (CMB) polarization, the SO aims to achieve various scientific goals including inflation, neutrinos, and the large-scale structure of the universe.
In the Sakurai Laboratory, we are responsible for the development of a sapphire half-wave plate system using superconducting magnetic bearings, optical windows with anti-reflection structures, and data analysis.

LiteBIRD is a JAXA-led scientific satellite project aiming for launch in 2032. It will conduct precision polarization observations of the cosmic microwave background (CMB) by three years full sky survey, to test the Cosmic Inflation, the most promising theory, describing the early universe era.
Sakurai Laboratory is in charge of instrumental developments of the LiteBIRD low-frequency telescope (especially polarization modulators), systematic analysis, galactic emission removal methods, and so on.

The millimeter-wave signals used in CMB experiments have various applications beyond cosmology, including communication, meteorology, and industry. To efficiently collect and detect this light, optical elements such as mirrors, lenses, and filters are essential. We aim to develop broad-bandwidth and high-precision low-temperature optical devices for applications in next-generation industries, such as space and extraterrestrial environments.