Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
Missile defense transfer radiometer (MDXR)
The Missile Defense transfer Radiometer (MDXR) is a cryogenic transfer radiometer for providing calibrations of collimated infrared beams in users' cryo-vacuum test facilities against the NIST primary optical power standards. The MDXR has both a filter radiometer and a cryogenic Fourier transform spectrometer (Cryo-FTS), both of which operate in vacuum at a temperature below 20 kelvin, and interfaces to customer chambers through an end flange. The Cryo-FTS provides continuous spectral coverage from 4 μm to 20 μm. An onboard absolute cryogenic radiometer (ACR) provides spectrally integrated power measurements down to a noise floor of approximately 3.5 pW. An onboard 7 cm collimator and cryogenic blackbody serve as a stability monitor and a spectral calibration source for the Cryo-FTS. The MDXR has been used multiple times at a variety of facilities since it was first operational in May 2010.
Specifications/Capabilities
- Measure absolute power with onboard ACR.
- Monitor and calibrate its own spectral throughput with onboard blackbody calibration source and 7 cm collimator.
- Fourier-transform spectrometer with spectral resolution of 0.85 cm-1 from 4 μm to 20 μm.
- Measure collimated beam with spectral irradiance input levels between 10-15 W/cm2/μm and 10-9 W/cm2/μm.
- Spectrally resolve beam over IR wavelengths from 2 µm to 30 µm with variable bandpass filters.
- Evaluate linear polarization of collimated beams.
- Easily transported with support equipment.
- Self-contained vacuum and cryogenic systems for operation external to test chamber being evaluated.