NASA EOS-AURA High Resolution Dynamics Limb Sounder (HIRDLS)
1990 - 2002
Project overview
The High Resolution Dynamics Limb Sounder (HIRDLS) instrument is a Limb Viewing Radiometer which was launched on the NASA EOS-Chem Satellite in 2004. Measurements of radiance from the thermal emission of trace chemical elements in the atmosphere is performed through a cooled infrared optical system. It has 21 spectral channels precisely defined by our filters contained within a focal plane detector assembly array. We are also responsible for the 21 "Ghost Image" suppressing filters positioned at the cold (60K) detector plane. These are very small in size - 1180mm x 440mm.
Our work is to make the two sets of 21 precision bandpass filters together with ultra broadband antireflection coatings for the lenses and windows of the instrument. The work is funded by a NERC research grant. Our responsibilities as co-investigators in the project include the complete end to end spectral design of the instrument. The filters are the most demanding we have ever had to make, combining as they do high spectral placement precision, the need to size by sawing, sub millimetre size, cryogenic use, and stringent quality assurance including state of the art spectral measurements of the finished items.
Delivered hardware
| Description | Filter Type | Quantity | Wavelength Region | Substrate Material | Dimensions |
| Cold Filters | Narrow bandpass filter | 21 channels | 6.0 - 18.0 µm | Germanium (Ge) | 1.39 mm L x 0.63 mm W x 0.45 mm T |
| Warm Filters | Narrow bandpass filter | 21 channels | 6.0 - 18.0 µm | Germanium (Ge) | 7.60 mm L x 3.40 mm W x 0.88 mm T |
| Dewar Window | Broadband antireflection coating | 1 channel | 6.0 - 18.0 µm | Zinc Selenide (ZnSe) | 30.0 mm Dia x 2.0 mm T |
| Lenses | Broadband antireflection coating | 2 channels | 6.0 - 18.0 µm | Germanium (Ge) | 64.0 mm Dia x 3.0 mm T |
| Gas Cell Window | Wide bandpass filters | 4 channels | 6.3 - 16.3 µm | Germanium (Ge) | 25.4 mm Dia x 1.5 mm T |
Partners
- Natural Environment Research Council (NERC)
- Rutherford Appleton Laboratory, Space Science and Technology Department
- University of Oxford, Department of Atmospheric, Oceanic and Planetary Physics
Publications
- G J Hawkins, R Hunneman, R E Sherwood, B M Barrett : " Infrared Filters and Coatings for the High Resolution Dynamics Limb Sounder (6-18µm)", Applied Optics, Vol 39, No 28, pp 5221-5230 (2000)
- G J Hawkins, R Hunneman : " A Spectral Performance Model for the High Resolution Dynamics Limb Sounder (6-18µm)", Infrared Physics and Technology, Vol 41, Issue 4, Pages 239-246 (2000)
- G J Hawkins, R Hunneman, J J Barnett, J G Whitney : " Spectral design and verification of HIRDLS filters and antireflection coatings using an integrated system performance approach", SPIE Proceedings, 3437, Pages 102-112 (1998)
- R Hunneman, G J Hawkins : " The manufacture and spectral assessment of the filters and antireflection coatings for use in the HIRDLS instrument", SPIE Proceedings, 3437, Pages 378-390 (1998)
- C Cole, R Hunneman, J W Bowen : " Synthesis of infrared filters for use in spaceflight systems", Proc. International Symposium on Optical Interference Coatings, Grenoble, France, SPIE, 2253-05, 42-50 (1994)
- G J Hawkins, R Hunneman, C Cole : " Infrared filters for space-flight focal plane array applications", SPIE Proceedings, 2253, Pages 333-347 (1994)
- R Hunneman, J J Barnett, G J Hawkins : " High-Performance Infrared Filters for the HIRDLS 21-Channel Focal Plane Detector Array", SPIE Proceedings, 2210-49, Pages 516-532 (1994)
Media
NASA Aura launch and mission science objectives
Damaged HIRDLS instrument still provides valuable data
Further information
Related news
- A 10-Year Endeavor: NASA's Aura and Climate Change - July 17, 2014
- 'Eye in the sky' watches over air - December 20, 2004
- Nasa launches its Aura satellite - July 15, 2004
Related links
Contact us
- Email:
irfilters@reading.ac.uk - Telephone:
+44 (0) 118 378 8224