Slide 1Progress towards Achieving On-Orbit SI Traceability for the CLARREO IR Payload
Hampton, VA, April 10, 2012
Recent results towards verification of measurement uncertainty for CLARREO IR
measurements
John Dykema
CLARREO SDT, 2012
Hampton, VA
Slide 2Progress towards Achieving On-Orbit SI Traceability for the CLARREO IR Payload
Hampton, VA, April 10, 2012
Viewing configuration providing immunity to polarization effects.
(used in combination with space view for instrument calibration)
(used for blackbody reflectivity and Spectral Response Module)
(Includes Multiple Phase Change Cells for absolute temperature calibration and Heated Halo for spectral reflectance measurement )
Heated Halo
(Measures instrument line shape)
QCL Laser
On-orbit Test/Validation (OT/V) ModulesWisconsin & Harvard Technology Developments Under NASA IIP
Slide 3Progress towards Achieving On-Orbit SI Traceability for the CLARREO IR Payload
Hampton, VA, April 10, 2012
DARI Testbed (1)
Slide 4Progress towards Achieving On-Orbit SI Traceability for the CLARREO IR Payload
Hampton, VA, April 10, 2012
QCL Housing: Optics, Thermal Management, Electronics
New kinematic lens mount
Slide 5Progress towards Achieving On-Orbit SI Traceability for the CLARREO IR Payload
Hampton, VA, April 10, 2012
Quantum Cascade Laser Housing – Exploded View
Purge valve
House-keeping sensor unit (T,p,RH)
Relief valve (for use during purge)
Emission window (AR coated ZnSe)
QCL device mounting clamp
Collimating optic/mount
Thermal cold plate
TEC and electrical connection
Mounting structure
Slide 6Progress towards Achieving On-Orbit SI Traceability for the CLARREO IR Payload
Hampton, VA, April 10, 2012
QCL Electronics and Built-In Housekeeping
Slide 7Progress towards Achieving On-Orbit SI Traceability for the CLARREO IR Payload
Hampton, VA, April 10, 2012
Collimation of 60°-40° output QCL device
AsphereQCL
Collimated Beam
Slide 8Progress towards Achieving On-Orbit SI Traceability for the CLARREO IR Payload
Hampton, VA, April 10, 2012
QCL Electronics Chassis
Slide 9Progress towards Achieving On-Orbit SI Traceability for the CLARREO IR Payload
Hampton, VA, April 10, 2012
Vacuum and Thermal Management
Slide 10Progress towards Achieving On-Orbit SI Traceability for the CLARREO IR Payload
Hampton, VA, April 10, 2012
OSRM: TRL 5
QCL w/integrated
housekeeping
Flip mirror
Electronics bus
QCL thermal management
Blackbodies for thermal testing
Chilled ethanol
Laser power meter
Slide 11Progress towards Achieving On-Orbit SI Traceability for the CLARREO IR Payload
Hampton, VA, April 10, 2012
Vacuum Test Results
Slide 12Progress towards Achieving On-Orbit SI Traceability for the CLARREO IR Payload
Hampton, VA, April 10, 2012
Vacuum Test Results (2)
Parameter Run 1 Run 2 Run 3 Run 4 Average
QCL Drive Current Noise 70 A 57 A 54 A 65 A 60 A
QCL Temperature Stability 0.024°C 0.021°C 0.014°C 0.019°C 0.020°C
TEC Current Noise 21 mA 14 mA 5 mA 10 mA 13 mA
Power Stability 0.45% 0.42% 0.33% 0.41% 0.4%
Results of vacuum test runs
Parameter Value
TEC Current, QCL maintained at 1 atm 0.95 A
TEC Current, QCL maintained under vacuum 1.01 A
Thermal requirements for different QCL packaging options
Slide 13Progress towards Achieving On-Orbit SI Traceability for the CLARREO IR Payload
Hampton, VA, April 10, 2012
DARI Testbed (2)
Slide 14Progress towards Achieving On-Orbit SI Traceability for the CLARREO IR Payload
Hampton, VA, April 10, 2012
OSRM: TRL 6
System level test with CO2 laser, integrating sphere: an absolute IR lineshape standard
Slide 15Progress towards Achieving On-Orbit SI Traceability for the CLARREO IR Payload
Hampton, VA, April 10, 2012
OSRM : CO2 to QCL ILS Comparison (1)
QCL, when T and I specifications
are met, matches CO2 laser lineshape
MCT Detector
Slide 16Progress towards Achieving On-Orbit SI Traceability for the CLARREO IR Payload
Hampton, VA, April 10, 2012
OSRM : CO2 to QCL ILS Comparison (2)
Pyroelectric Detector
Slide 17Progress towards Achieving On-Orbit SI Traceability for the CLARREO IR Payload
Hampton, VA, April 10, 2012
DARI Testbed ILS
Slide 18Progress towards Achieving On-Orbit SI Traceability for the CLARREO IR Payload
Hampton, VA, April 10, 2012
OCEM-QCL TRL 6
Surface Treatment Nominal 10 m reflectivity
Aeroglaze Z306 5%
Alion MH3300 10%
AZ Tech RM550IB 3%
Inferring emissivity from laser reflection
Slide 19Progress towards Achieving On-Orbit SI Traceability for the CLARREO IR Payload
Hampton, VA, April 10, 2012
Calibrated, Illuminated BlackbodiesM
CT
Det
ecto
r
Pyr
oele
ctric
Det
ecto
r
Slide 20Progress towards Achieving On-Orbit SI Traceability for the CLARREO IR Payload
Hampton, VA, April 10, 2012
Calculation of Power on Detector
Pyroelectric detector
MCT detector
Aperture at detector 1.8 mm 2.0 mm
Field stop Ø 38 mm 20 mm
Throughput 0.0089 cm2-sr 0.0038 cm2-sr
Power at detector, Z306
(6.6±0.7)×10-7 W (1.2±0.1)×10-7 W
Power at detector, MH2200
(2.4±0.2)×10-6 W (3.6±0.4)×10-8 W
Slide 21Progress towards Achieving On-Orbit SI Traceability for the CLARREO IR Payload
Hampton, VA, April 10, 2012
div angle
Optical Modeling for OCEM-QCL
Reflected Laser Light to FTS and Detector
Slide 22Progress towards Achieving On-Orbit SI Traceability for the CLARREO IR Payload
Hampton, VA, April 10, 2012
Compute Cavity Emissivity
Pyroelectric detector estimate
MCT detector estimate
MH2200 = 0.9959 ±0.00004 MH2200 = 0.9951 ±0.00005
Z306 = 0.9989 ±0.00001 Z306 = 0.9988 ±0.00001
f
surfacesurface
surfacecavity
C
1 Cf=39 (Knuteson et al.
J.TECH 2004)
Slide 23Progress towards Achieving On-Orbit SI Traceability for the CLARREO IR Payload
Hampton, VA, April 10, 2012
QCL Subsystem: Pathway to TRL 7
Slide 24UW & Harvard NASA IIP Activities in Support of CLARREO
Year-2.5 Review, January 31, 2011
TEC Controller
PowerConditioning Switching
RegulatorController
+
-Filter
Setpoint Temperature
Offset
β
OutputPower In+
-
Current Sensing
FB
Slide 25Progress towards Achieving On-Orbit SI Traceability for the CLARREO IR Payload
Hampton, VA, April 10, 2012
TEC Controller
• Single Supply Operation
• High Efficiency
• No Heat Sink Necessary
• Buffered Temperature Readout
• Remote/Local Setpoint
Slide 26Progress towards Achieving On-Orbit SI Traceability for the CLARREO IR Payload
Hampton, VA, April 10, 2012
V/I Board
To LASER
ModifiedHowlandCurrentSource
LASERProtection
+
-
InputWaveform
Voltage Monitoring
Current Monitoring
Temperature Monitoring
V
I
T
PowerMonitoring
+VIN
-
IOUT
Slide 27Progress towards Achieving On-Orbit SI Traceability for the CLARREO IR Payload
Hampton, VA, April 10, 2012
V/I Board
• Single Supply Operation
• No Heat Sink Required– (depending on LASER current)
• Multiple Monitoring Options:– LASER Voltage, Current (Power)– LASER Temperature
• ESD Protection
In Situ Temperature
Temporal Drift in Measurement
= Satellite overpass
Spatial Drift in Measurement
First Assessment of Uncertainty Practices
From Immler et al., AMT 2010
Atmospheric Satellite Measurement
Satellites make wavelength-dependent measurements of radiance R: retrieve x (temperature, humidity, clouds, trace gases, surface properies)
01 xRLx
)(xLR
Infrared Profiling Process
Site Atmospheric State Best Estimate
• Radiosondes drift in time and space• Radiosondes ascent time much greater than
satellite measurement length• Solution: use ancillary measurements to
interpolate in space and time• One approach: Tobin et al., “Atmospheric
Radiation Measurement site atmospheric state best estimates for Atmospheric Infrared Sounder temperature and water vapor retrieval validation,” JGR 2006
• See also Calbet et al., AMT, 2011
Tobin 2006 Approach to SASBE
• Two sondes were launched within 2 hours of overpass time
• Interpolate sonde profiles in time with IR-based atmospheric profiling
• Interpolate sonde profiles in space with geostationary measurements
• Perform weighted average of interpolated profiles to get best estimate of atmospheric column
Practical Blackbody:
•Finite Aperture •Temperature Gradients
Blackbody Calibration and Uncertainty
Uncertainty Assessment for Vector Quantities
2211 TTT SASBE
)cov()cov()cov( 2221
21 TTT SASBE
RLJ 1
jiij uu
TJuJx )cov()cov( 0
1 xRLx
Uncertainty Assessment: In Situ Temperature Profile TSASBE
Uncertainty Assessment: Infrared Temperature Profile x
Acknowledgements
• Thanks to NASA for:– IIP funding (ESTO)– IPT funding (LaRC)– SDT funding
