112 lines
4.3 KiB
Python
112 lines
4.3 KiB
Python
from ..ITransmissive import ITransmissive
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from abc import abstractmethod
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from ..SpectralQty import SpectralQty
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from esbo_etc.lib.helpers import error
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import astropy.units as u
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from astropy.modeling.models import BlackBody
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class AOpticalComponent(ITransmissive):
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"""
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Abstract super class for an optical component
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"""
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@abstractmethod
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@u.quantity_input(obstructor_temp=[u.K, u.Celsius])
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def __init__(self, parent: ITransmissive, transreflectivity: SpectralQty = None,
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noise: SpectralQty = None, obstruction: float = 0, obstructor_temp: u.Quantity = 0 * u.K,
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obstructor_emissivity: float = 0):
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"""
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Initialize a new optical component
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Parameters
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----------
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parent : ITransmissive
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The parent element of the optical component from which the electromagnetic radiation is received
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transreflectivity : SpectralQty
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The spectral transmission / reflectivity coefficient of the component. This coefficient is multiplied with
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the incoming radiation from the parent element in order to propagate the incoming radiation through the
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optical component.
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noise : SpectralQty
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The noise created by the optical component. This noise will be added to the propagated incoming noise in
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order to calculate the overall noise.
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obstruction : float
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The additional obstruction factor of the optical component. 0 means the component is not obstructed, 1
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denotes a completely obstructed component with therefore no incoming flux. It is important to note, that
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the obstruction factor reflects the obstruction of the optical component additionally to the obstruction
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factors of the prior elements in the beam.
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obstructor_temp : Quantity in Kelvin / Celsius
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Temperature of the obstructing component.
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obstructor_emissivity : float
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Emissivity of the obstructing component.
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"""
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self._parent = parent
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if transreflectivity:
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self._transreflectivity = transreflectivity
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if noise:
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self._noise = noise
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self._obstruction = obstruction
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self._obstructor_temp = obstructor_temp
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self._obstructor_emissivity = obstructor_emissivity
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def calcSignal(self) -> SpectralQty:
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"""
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Calculate the spectral flux density of the target's signal
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Returns
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-------
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signal : SpectralQty
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The spectral flux density of the target's signal
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"""
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return self.propagate(self._parent.calcSignal()) * (1 - self._obstruction)
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def calcNoise(self) -> SpectralQty:
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"""
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Calculate the spectral radiance of the target's noise
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Returns
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-------
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noise : SpectralQty
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The spectral radiance of the target's noise
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"""
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parent = self.propagate(self._parent.calcNoise())
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if self._obstructor_temp > 0 * u.K:
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bb = BlackBody(temperature=self._obstructor_temp, scale=1. * u.W / (u.m ** 2 * u.nm * u.sr))
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obstructor = bb(parent.wl) * self._obstructor_emissivity
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return parent * (1. - self._obstruction) + obstructor * self._obstruction + self.ownNoise()
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else:
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return parent * (1. - self._obstruction) + self.ownNoise()
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def propagate(self, sqty: SpectralQty) -> SpectralQty:
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"""
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Propagate incoming radiation through the optical component
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Parameters
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----------
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sqty : SpectralQty
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The incoming radiation
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Returns
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-------
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sqty : SpectralQty
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Manipulated incoming radiation
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"""
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if hasattr(self, "_transreflectivity"):
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return sqty * self._transreflectivity
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else:
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error("Transreflectivity not given. Method propagate() needs to be implemented.")
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def ownNoise(self) -> SpectralQty:
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"""
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Calculate the noise created by the optical component
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Returns
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-------
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sqty : SpectralQty
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The noise created by the optical component
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"""
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if hasattr(self, "_noise"):
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return self._noise
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else:
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error("noise not given. Method ownNoise() needs to be implemented.")
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