Post on 31-Dec-2015
description
EEM calculations in FRED
Mikkel BrydegaardApplied Molecular Spectroscopy & Remote Sensing
Atomic Physics, LTH
Project
Components
• Fiber tip source
• Off axis parabolic mirror
• Quartz prism
• Achromat
• Sample window
• Chassis
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
Collimating mirror
• Newport. Off-Axis Replicated Parabolic Mirror, 1.500 in. Dia, 4.000 in. EFL, Protected Aluminum Coating
Prism
• Esco products
• Equilatheral fused silica
• 40mm sides
• 35° mean dispersion 300-900nm
• 40*cos(30+35/2)=27mm apperture
• Displacement of optical axis from center of circumcicle of prism 8.93 mm
Achromat
• Edmund optics
• Uncoated triplet
• CaF2 Fused Silica CaF2
• Provided raytracing object from edmund upon signed request
Sample slit
• Quartz microscope cover slide
• Mirror coating
• Nano church
Chassis
• Imported from Alibre design
• Anodized aluminum
• Black lambertian 4%
• Contribution
Setup
Fiber tip
Newportv Off-axis paraboloid
EscoQuartzprismQuartz
window
Edmund achromatCaF2-QS
Properties of interest
• Throughput
• Spectral resolution
• Signal to background
Simulation variables
• Ray numbers
• Allow reflections
• Allow surface scatters
Resulting rays
End rays C1 C2 C3
R1 175 3855 24710
R2 2405 66122 430448
R3 14560 418750 2693084
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
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%
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
Added background
Background C1 C2 C3
R1 0,00E+00 4,70E-03 2,16E-04
R2 0,00E+00 1,40E-03 1,65E-05
R3 0,00E+00 9,09E-04 2,73E-06
Signal and back ground contributions
3.5E0 1E-3
3E-6
Spatial profile of background contributions
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