Focal Plane

Seimei telescope has two Nasmyth foci. Multiple instruments are mounted on the instrument rotator on the red-painted Nasmyth platform, and Exoplanet Imager with Coronagraphic Adaptive Optics, SEICA is located on the blue-painted Nasmyth platform. The focus is changed with rotating the tertiary mirror.

"Red" Nasmyth Platform

The instrument rotator on the red Nasmyth platform has 3 types ports, a large instrument flange, a small instrument flange, and an optical-fiber stage. Observers can select a suitable instrument by switching the optical path with motorized pick-off mirrors.

Specification of the instrument rotator.

Large Instrument flange

The flange can be equipped with instruments up to 1150mm in diameter and 1000kgw in weight.

The instrument on the flange can be used with the auto-guider and the comparison lamps.

Available Instrument

• Tricolor CMOS Camera and Spectrograph, TriCCS

Short-term observation with the visitor instrument is available.

Small Instrument flange

The flange can mount multiple small instruments (typical size: W200 x H200 x L300 mm).

Available Instrument

• The entrance optics of High-dispersion Echelle Spectrograph for Radial Velocimetry, GAOES-RV
• RGB camera

Support tools

• Pointing Camera
• Auto-guider
• Shack-Hartmann Camera
• PCS
• Comparison Lamps

New small instruments are acceptable for the flange.

Optical-Fiber Stages

The instrument rotator has two optical-fiber stages, and each stage has three optical-fiber mounting positions. Optical-fiber instruments can be used with the auto-guider and the comparison lamps.

Available Instrument

• Optical Low-dispersion Spectrograph with Integral Field Unit, KOOLS-IFU

New optical-fiber instruments are acceptable for the stages.

"Blue" Nasmyth Stage

Exo-planet finder Exoplanet Imager with Coronagraphic Adaptive Optics, SEICA will occupy the stage for the time being.