NISP simulations (collimated beam)¶
Author: Yannick Copin y.copin@ipnl.in2p3.fr
We apply the naive spectrograph model (i.e. including a grism in a collimated beam) to the NISP instrument.
In [1]:
# Technical stuff related to the Jupyter notebook
%load_ext autoreload
%autoreload 2
%matplotlib inline
import mpld3
mpld3.enable_notebook()
import warnings
warnings.filterwarnings("ignore")
In [2]:
import numpy as N
from matplotlib import pyplot as P
from spectrogrism import spectrogrism as S
from spectrogrism import nisp
Zemax simulations¶
Load the Zemax simulations:
In [3]:
datapath = "../spectrogrism/data/"
simulations = S.Configuration([
("name", "Zemax"),
(1, datapath + "run_190315.dat"), # 1st-order dispersed simulation
(0, datapath + "run_011115_conf2_o0.dat"), # 0th-order dispersed simulation
(2, datapath + "run_161115_conf2_o2.dat"), # 2nd-order dispersed simulation
('J', datapath + "run_071215_conf6_J.dat"), # J-band undispersed simulation
])
print(simulations)
----------------------- Configuration 'Zemax' ------------------------
name : Zemax
1 : ../spectrogrism/data/run_190315.dat
0 : ../spectrogrism/data/run_011115_conf2_o0.dat
2 : ../spectrogrism/data/run_161115_conf2_o2.dat
J : ../spectrogrism/data/run_071215_conf6_J.dat
In [4]:
zmx_pos = nisp.ZemaxPositions(simulations)
print(zmx_pos)
Simulations 'Zemax': 4 modes
Order #1: ../spectrogrism/data/run_190315.dat
Order #0: ../spectrogrism/data/run_011115_conf2_o0.dat
Order #2: ../spectrogrism/data/run_161115_conf2_o2.dat
Band J: ../spectrogrism/data/run_071215_conf6_J.dat
Wavelengths: 13 steps from 1.20 to 1.80 µm
Coords: 289 sources
Plot input sources:
In [5]:
ax = zmx_pos.plot_input()
In [6]:
simcfg = zmx_pos.get_simcfg() # Simulation configuration
print(simcfg)
------------------ Simulation configuration 'Zemax' ------------------
name : Zemax
wave_npx : 13
wave_range : [1.1999999999999999e-06, 1.7999999999999999e-06]
modes : [1, 0, 2, 'J']
input_coords : [[-0.00698132 -0.00698132]
[-0.00698132 -0.00610865]
[-0.00698132 -0.00523599]
...,
[ 0.00698132 0.00523599]
[ 0.00698132 0.00610865]
[ 0.00698132 0.00698132]]
Optical modeling¶
We use here the standard/naive “collimated” model: telescope + collimator + [grism] + camera + detector.
Spectroscopy mode¶
In [7]:
# Optical modeling
optcfg = nisp.NISP_R # Optical configuration (default NISP)
print(optcfg)
------------------- Optical configuration 'NISP-R' -------------------
name : NISP-R
wave_ref : 1.5e-06
wave_range : [1.25e-06, 1.85e-06]
telescope_flength : 25.2
grism_dispersion : 9.8
grism_prism_material: FS
grism_grating_material: FS
grism_prism_angle : 0.0471238898038
grism_grating_rho : 13.1
grism_grating_blaze : 0.0453785605519
detector_pxsize : 1.8e-05
collimator_flength : 1.946
collimator_distortion: 0.0028
grism_prism_tiltx : 0
grism_prism_tilty : 0
grism_prism_tiltz : 0
camera_flength : 0.957
camera_distortion : 0.0296
detector_dx : 0.0007
detector_dy : -0.0042
In [8]:
spectro = S.Spectrograph(optcfg,
telescope=S.Telescope(optcfg))
print(spectro)
---------------------------- Spectrograph ----------------------------
Telescope: f=25.2 m
Null geometric distortion
Null chromatic distortion
Collimator: f=1.9 m
Geometric distortion: center=(+0.000, +0.000) mm, K-coeffs=[ 0.0028], P-coeffs=[]
Null chromatic distortion
Grism:
Prism [FS]: A=2.70°, tilts=+0',+0',+0'
Grating [FS]: rho=13.1 g/mm, blaze=2.60°
1st-order null-deviation wavelength: 1.59 µm
Camera: f=1.0 m
Geometric distortion: center=(+0.000, +0.000) mm, K-coeffs=[ 0.0296], P-coeffs=[]
Null chromatic distortion
Detector: pxsize=18 µm
Offset=(+0.700, -4.200) mm, angle=0.0 deg
Spectrograph magnification: 0.492
Central dispersion: 13.73 AA/px at 1.50 µm
In [9]:
print(" Spectrograph round-trip test ".center(70, '-'))
for mode in simcfg.get('modes', (1, 0, 2)):
if not spectro.test(simcfg.get_wavelengths(optcfg), mode=mode, verbose=False):
warnings.warn("Order #{}: backward modeling does not match.".format(mode))
else:
print("{}: OK".format(S.str_mode(mode)))
-------------------- Spectrograph round-trip test --------------------
Order #1: OK
Order #0: OK
Order #2: OK
Band J: OK
In [10]:
spe_pos = spectro.predict_positions(simcfg, orders=zmx_pos.orders)
spe_pos.test_compatibility(zmx_pos) # Would raise IndexError if incompatible
In [11]:
subsampling = 3 # Subsample output plot
kwargs = dict(s=20, edgecolor='k', linewidths=1) # Outlined symbols
ax = zmx_pos.plot_output(modes=zmx_pos.orders, subsampling=subsampling, **kwargs)
kwargs = {} # Default
for order in zmx_pos.orders:
# Compute RMS on spectra positions
rms = zmx_pos.compute_rms(spe_pos, mode=order)
print("Order #{} RMS = {:.4f} mm = {:.2f} px".format(order, rms / 1e-3, rms / spectro.detector.pxsize))
spe_pos.plot(ax=ax, zorder=0, # Draw below Zemax
modes=(order,),
subsampling=subsampling,
label="{} #{} (RMS={:.1f} px)".format(spe_pos.name, order, rms / spectro.detector.pxsize),
**kwargs)
ax.axis([-100, +100, -100, +100]) # [mm]
ax.set_aspect('equal', adjustable='datalim')
ax.legend(fontsize='small', frameon=True, framealpha=0.5, title='')
ax.figure.set_size_inches(12, 10)
Order #1 RMS = 0.1844 mm = 10.25 px
Order #0 RMS = 0.3509 mm = 19.50 px
Order #2 RMS = 0.4524 mm = 25.13 px
In [12]:
fig, axs = P.subplots(1, 3)
# Position offset quiver plots
for ax, order in zip(axs.ravel(), zmx_pos.orders):
zmx_pos.plot_offsets(spe_pos, ax=ax, mode=order)
ax.set_aspect('equal', adjustable='box')
ax.set_title("Order #{}".format(order))
fig.set_size_inches(12, 5)
Imagery mode¶
In [13]:
phot_pos = spectro.predict_positions(simcfg, modes=zmx_pos.bands)
phot_pos.test_compatibility(zmx_pos)
kwargs = dict(s=20, edgecolor='k', linewidths=1) # Outlined symbols
ax = zmx_pos.plot_output(modes=zmx_pos.bands, **kwargs)
kwargs = {} # Default
for band in zmx_pos.bands:
# Compute RMS on positions
rms = zmx_pos.compute_rms(phot_pos, mode=band)
print("Band {} RMS = {:.4f} mm = {:.2f} px".format(
band, rms / 1e-3, rms / spectro.detector.pxsize))
phot_pos.plot(ax=ax, zorder=0, # Draw below Zemax
modes=(band,),
label="{} {} (RMS={:.1f} px)".format(
phot_pos.name, band, rms / spectro.detector.pxsize),
**kwargs)
ax.axis([-100, +100, -100, +100]) # [mm]
ax.set_aspect('equal', adjustable='datalim')
ax.legend(fontsize='small', frameon=True, framealpha=0.5, title='')
ax.figure.set_size_inches(12, 10)
Band J RMS = 4.6598 mm = 258.88 px