NIST Infrared Spectrophotometry Overview
FT-IR Spectrometers
Fixed
IR Lasers
Tunable
Specialized Accessories
 Integrating Spheres
 Goniometer
 Cryostats & Heaters
 Emittance System
Total Integrated Scatter
Materials, Coatings & Optical Components
Measurement Methodologies
Error Sources Evaluation
Modeling Instruments &
Methods
Absolute Methods r, t, a, e
Direct Measurements & Properties
Transmittance
Regular
Diffuse, BTDF
Reflectance
Regular
Diffuse,BRDF
Ellipsometry
Absorptance
Emittance
Polarimetry
Calibration Service
Reference Data
Physical Standards
Intercomparisons
Derived Quantities
Index of Refraction
Extinction Coefficient
External:
Industry
Government
Academia
Internal:
Detectors
Sources
Materials
Infrared Index of Refraction
• UV-VIS System available for extension to IR
• NIST is willing to pursue IR index effort
• Will require about 0.5 to 1 SY to accomplish
• Requires
1.
Justification
2.
Funding
3.
Sufficient 1. may lead to 2.
• Also need specifics, materials, uncertainties, spectral
range, etc.
NIST Precision Refractometry
John Burnett, Eric Benck, Simon Kaplan
sample prism
entrance/collimation box
exit/collimation box (rotates)
detector
entrance slit
exit slit
temp control system
goniometer
purged
sample chamber
Refractrometry Facility located
at NIST AML 217/F117
Minimum Deviation Refractometry System – Custom NIST Design
 All reflective optics + purge housing  operates from vacuum UV (120 mm) to IR.
 Operates normally near room T (15 - 25 C). Upgradable for cryogenic and other T’s.
 Accuracy
- FL=0.5 m, F/# = 10.
- Goniometer: absolute angle accuracy  0.5 arc-sec.
- Feedback temperature control to  10 mK .
 Absolute index accuracy  1  10-6 routinely attained in UV.
Primary Uses
 Index of precision optics (e.g., SiO2, CaF2, MgF2) for litho industry (1ppm level @633 nm – 157 nm).
 Index of general optical materials for science and technology.
 Index of fluids.
 Thermo-Optic Coefficient of optical materials and fluids.
(Also have separate high-accuracy dedicated dn/dT system.)