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.


NAOS WFS characteristics

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

NAOS dichroics characteristics

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