How to set up …¶
The telescope¶
This section contains the parameters related to the telescopen:
[telescope]
TelescopeDiameter = 38.5
ZenithAngle = 30.0
ObscurationRatio = 0.28
Resolution = 480
to the pupil:
# path to the pupil model in .fits file - optional (if provided, the pupil model is interpolated) - default: ''
PathPupil = 'data/EELT480pp0.0803m_obs0.283_spider2023.fits'
PupilAngle = 0.0
to additional aberrations (in the main path or NCP):
PathStaticOn = '../P3/aoSystem/data/ELT_CALIBRATION/CombinedError_Wavefront_nm.fits'
PathApodizer = ''
PathStatModes = ''
or:
# extra error in the science FoV (error not included in TIPTOP like NCPA, optics quality, ...)
extraErrorNm = 160
extraErrorExp = -2
extraErrorMin = 0
# extra error in the technical FoV (error not included in TIPTOP like NCPA, optics quality, ...)
extraErrorLoNm = 132
extraErrorLoExp = -2
extraErrorLoMin = 0
to windshake and additional tilt jitter:
# ELT tip & tilt wind shake when wind speed on M2 is 8 m/s
windPsdFile = 'data/morfeo_windshake8ms_psd_2022_1k.fits'
# jitter_FWHM --> 10 nm RMS tip error is 0.505arcesc
jitter_FWHM = 3.5
to the size of the technical field:
TechnicalFoV = 160.0
and to the global focus control:
# ground layer focus is controlled with NGS WFS
glFocusOnNGS = True
The atmosphere¶
This section contains the atmospheric parameters, seeing (or r0), L0, Cn2 profile and wind profile:
[atmosphere]
Wavelength = 500e-9
Seeing = 0.8
L0 = 22.0
Cn2Weights = [0.59, 0.02, 0.04, 0.06, 0.01, 0.05, 0.09, 0.04, 0.05, 0.05]
Cn2Heights = [30, 140, 281, 562, 1125, 2250, 4500, 7750, 11000, 14000]
WindSpeed = [6.6, 5.9, 5.1, 4.5, 5.1, 8.3, 16.3, 10.2, 14.3, 17.5]
WindDirection = [0., 0., 0., 0., 90., -90., -90., 90., 0., 0.]
The adaptive optics system¶
Before diving into the different sections you need to figure what kind of AO system you want among the following:
Single Conjugate Adaptive Optics¶
The Single Conjugate Adaptive Optics system is described here: ESO - AO MODES - SCAO
The wavefront sensor¶
The Wavefront Sensor in a SCAO system (natural guide star only) can be a Pyramid sensor:
[sensor_HO]
# WFS type - optional - default : Shack-Hartmann
WfsType = 'Pyramid'
# Spot modulation radius in lambda/D units for pyramid WFS - optional - default : None
Modulation = 3
# HO WFS pixel scale in [mas] - required
PixelScale = 220
# Number of pixels per subaperture - required
FieldOfView = 600
# Flux return in [nph/frame/subaperture] - required
NumberPhotons = [500]
# read-out noise std in [e-] - required
SigmaRON = 1.0
# dark current[e-/s/pix] - optional - default: 0.0
Dark = 0.2
# Sky background [e-/s/pix] - optional - default: 0.0
SkyBackground = 0.6
# excess noise factor - optional - default: 2.0
ExcessNoiseFactor = 1.0
# Number of WFS lenslets - required
NumberLenslets = [100]
or a Shack-Hartmann sensor:
[sensor_HO]
WfsType = 'Shack-Hartmann'
Modulation = None
PixelScale = 832
FieldOfView = 6
Binning = 1
NumberPhotons = [100.0]
SigmaRON = 0.2
ExcessNoiseFactor = 2.0
# CoG computation algorithm - optional -defaut:'wcog'
Algorithm = 'wcog'
# Number of pixels for windiwing the low order WFS pixels - optional - default: 2
WindowRadiusWCoG = 2
NumberLenslets = [40]
Then a section with the guide star must be present:
[sources_HO]
# Sensing wavelength for HO modes in meters - required
Wavelength = 950e-9
# list of polar coordinates of the guide stars sources; zenith in arcsec and azimuth in degrees - optional - default [0.0]
Zenith = [0.0]
Azimuth = [0.0]
# altitude of the guide stars (0 if infinite) - optional - default: 0.0
Height = 0.0
The deformable mirror¶
The deformable mirror is used to achieve wavefront control and correction and this section contains the following parameters:
[DM]
# DM actuators pitch in meters - required
NumberActuators = [80]
# DM actuators pitch in meters - required
DmPitchs = [0.38]
# DM influence function model - optional - default: 'gaussian'
InfModel = 'gaussian'
# DM influence function model mechanical coupling- optional - default: [0.2]
InfCoupling = [0.2]
# DM altitude in m - optional - default: [0.0]
DmHeights = [600.0]
# Zenith position in arcsec - optional - default: [0.0]
OptimizationZenith = [0]
# Azimuth in degrees - optional - default: [0.0]
OptimizationAzimuth = [0]
# Weights - optional - default: [1.0]
OptimizationWeight = [1]
# Matrix Conditioning - optional - default: 1e2
OptimizationConditioning = 1.0e2
# Number of reconstructed layers for tomographic systems - optional - default: 10
NumberReconstructedLayers= 10
# Shape of the AO-corrected area - optional - default: 'circle'
AoArea = 'circle'
The real time controler¶
This section contains the details of the control, the framerate and the delay:
[RTC]
# HO Loop gain - required
LoopGain_HO = 0.5
# HO loop frequency in [Hz] - required
SensorFrameRate_HO = 500.0
# HO loop frame delay - required
LoopDelaySteps_HO = 1
Multi Conjugate Adaptive Optics¶
The Multi Conjugate Adaptive Optics system is described here: ESO - AO MODES - MCAO
The wavefront sensor¶
For an MCAO system with multiple NAtural Guide Stars (NGSs), the difference here is that NumberPhotons and NumberLenslets are vectors as are Zenith and Azimuth in the soruces_HO section.
If the system have Laser Guide Stars (LGSs) and NGSs these sections are present:
[sources_LO]
Wavelength = [1650e-9]
Zenith = [66.6, 79.3, 69.0]
Azimuth = [221.7, 321.2, 106.6]
[sensor_LO]
PixelScale = 16.0
FieldOfView = 100
Binning = 1
# zero magnitude flux 8.17e11ph/s (H band)
# magnitudes 10.7, 16.3, 14.5
# 2x2 sub-apertures and 250 Hz framerate
# --> 8.17e11*10**(-[10.7,16.3,14.5]/2.5)/4/250.
NumberPhotons = [42900,247,1300]
SpotFWHM = [[0.0,0.0,0.0]]
SigmaRON = 0.5
Dark = 40.0
SkyBackground = 120.0
Gain = 1.0
ExcessNoiseFactor = 1.3
# note 2x2 is required to provide focus control
# (see glFocusOnNGS in telescope section)
NumberLenslets = [2, 2, 2]
Algorithm = 'wcog'
WindowRadiusWCoG = 'optimize'
ThresholdWCoG = 0.0
NewValueThrPix = 0.0
noNoise = False
filtZernikeCov = True
The deformable mirror¶
For an MCAO system with multiple DM, the difference here is that NumberActuators, DmPitchs, InfCoupling and DmHeights are vectors.
The real time controler¶
If the system have Laser Guide Stars (LGSs) and NGSs this section has the following parameters:
LoopGain_LO = 'optimize'
SensorFrameRate_LO = 250.0
LoopDelaySteps_LO = 1
Laser Tomography Adaptive Optics¶
The Laser Tomography Adaptive Optics system is described here: ESO - AO MODES - LTAO
The wavefront sensor¶
As for the MCAO system when LGSs and NGSs are present the sections [sources_LO] and [sensor_LO] must be added.
The deformable mirror¶
Like for a SCAO system.
The real time controler¶
Like for a MCAO system with LGSs and NGSs.
Gound Layer Adaptive Optics¶
The Ground Layery Adaptive Optics system is described here: ESO - AO MODES - GLAO
The wavefront sensor¶
Like for a MCAO system.
The deformable mirror¶
Like for a SCAO system.
The real time controler¶
Like for a MCAO system.