EEM calculations in FRED

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EEM calculations in FRED

• Mikkel Brydegaard
• Applied Molecular Spectroscopy Remote
  SensingAtomic Physics, LTH

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Project
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Components

• Fiber tip source
• Off axis parabolic mirror
• Quartz prism
• Achromat
• Sample window
• Chassis

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Source

• Ocean Optics ø230 µm circular fiber tip
• 24 acceptance angle
• Apperture to 6 for collimating mirror
• Simulated spectral content 300, 350, 400, 500
  and 900 nm

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Collimating mirror

• Newport. Off-Axis Replicated Parabolic Mirror,
  1.500 in. Dia, 4.000 in. EFL, Protected Aluminum
  Coating

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Prism

• Esco products
• Equilatheral fused silica
• 40mm sides
• 35 mean dispersion 300-900nm
• 40cos(3035/2)27mm apperture
• Displacement of optical axis from center of
  circumcicle of prism 8.93 mm

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Achromat

• Edmund optics
• Uncoated triplet
• CaF2 Fused Silica CaF2
• Provided raytracing object from edmund upon
  signed request

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Sample slit

• Quartz microscope cover slide
• Mirror coating
• Nano church

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Chassis

• Imported from Alibre design
• Anodized aluminum
• Black lambertian 4
• Contribution

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Setup
Newportv Off-axis paraboloid
Edmund achromatCaF2-QS
EscoQuartzprism
Quartzwindow
Fiber tip
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Properties of interest
Simulation variables

• Throughput
• Spectral resolution
• Signal to background

• Ray numbers
• Allow reflections
• Allow surface scatters

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Resulting rays
End rays C1 C2 C3
R1 175 3855 24710
R2 2405 66122 430448
R3 14560 418750 2693084
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Simulation time
Calculation time C1 C2 C3
R1 0.933 sec 5.94 secs 31.2 secs
R2 6.25 secs 50.2 secs 8.76 mins
R3 35.6 secs 5.23 mins 54.2 mins
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Throughput
Throughput C1 C2 C3
R1 56,62 56,85 56,85
R2 60,95 61,23 61,23
R3 61,55 61,85 61,85
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FWHM
FWHM mm C1 C2 C3
R1 0.115 0.147 0.147
R2 0.146 0.146 0.146
R3 0.136 0.136 0.136
FWHM nm C1 C2 C3
R1 14.30 18.33 18.33
R2 18.14 18.14 18.14
R3 16.91 16.93 16.93
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Added background
Background C1 C2 C3
R1 0,00E00 4,70E-03 2,16E-04
R2 0,00E00 1,40E-03 1,65E-05
R3 0,00E00 9,09E-04 2,73E-06
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Signal and back ground contributions
1E-3
3.5E0
3E-6
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Spatial profile of background contributions
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Experiences

• Prism displacement
• Ommitment of achromat, in accordance with
  Spectrograph design fundamentals / J.F. James.
• More stray light along slit than perpendicular to
  it
• Parabolic mirrors in FRED