NAOS Characteristics
NAOS is an adaptive optics system equipped with both visible and infrared,Shack-Hartmann type, wavefront sensors.
Typical magnitude limits for the AO guide star are: V=16.7 and K=12 (13 with the N90C10 dirchoic) at a maximal distance of 55".
NAOS contains 5 dichroics which split the light from the telescope between CONICA and the NAOS wavefront sensors.
Characteristics | Vis. WFS | IR WFS For the N20C80 dichroic |
Wavelength range | 0.45 - 1.0 μm | 0.8 - 2.5 μm |
14x14: FOV per lenslet | 2.32" | 5.15" |
magnitude range | 0 - 12 | 4 - 9 |
7x7: FOV per lenslet | 4.64" | 4.8" and 5.15" |
magnitude range | 12 - 16.7 | 9 - 12 |
Dichroic | Reflected light to the WFS | Efficiency | Transmitted light to CONICA | Efficiency | Conditions of use |
VIS | V,R,I (0.45 - 0.95 μm) |
90% | J, H, K, L, M (1.05 - 5.0 μm) |
90% | near-IR observations with Vis. WF sensing |
N20C80 | V,R,I,J,K (0.45 - 2.55 μm) |
20% | V, R, I, J, H, K (0.45 - 2.55 μm) |
80% | WF sensing and observing in the infrared |
N90C10 | V,R,I,J,K (0.45 - 2.55 μm) |
90% | V, R, I, J, H, K
(0.45 - 2.55 μm)
|
10% | WF sensing and observing in the infrared |
JHK | I,J,H,K (0.80 - 2.55 μm) |
90% | L , M (2.8 - 5.5 μm) |
90% | thermal-IR observations with IR. WF sensing |
K | K (1.9 - 2.55 μm) |
90% | V, R, I, J, H (0.45 - 1.8 μm) |
90% | J, H observations with WF sensing in K |