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Special tests of aperture area
Special tests of aperture area
Primary NIST Technical Contact:
Secondary NIST Technical Contact:
Measurements of the geometric area of optical apertures are available for circular, elliptical, and rectangular apertures. All measurements are made using NIST’s Aperture Area Measurement (AAM) instrument, a non-contact optical coordinate measuring machine. Apertures with diameters ranging from 0.5 mm to 50 mm are measured routinely. Aperture areas are reported with an estimate of the measurement uncertainty. Arrangements for aperture area measurements must be made before apertures are shipped to NIST to ensure that the apertures can be measured with the AAM system. The decision to perform an aperture area measurement rests with NIST. Apertures not suitable for measurement will be returned.
High Accuracy Measurement of Aperture Area Relative to a Standard Known Aperture, J. B. Fowler and G. Dezsi, J. Res. Natl. Inst. Stand. Technol. 100(3), 277-283, (1995).
Report on the CCPR-S2 Supplementary Comparison of Area Measurements of Apertures for Radiometry, M. Litorja and J. Fowler (Jan. 2007).
Summary of high-accuracy aperture-area measurement capabilities at the NIST, J. B. Fowler, R. D. Saunders, and A. C. Parr, Metrologia 37, 621-623 (2000).
Geometric area measurements of circular apertures for radiometry at NIST, J. Fowler and M. Litorja, Metrologia 40, S9-S12 (2003).
Please contact the NIST Technical Contact listed above before sending your equipment for calibration and to confirm shipping to address information.
Shipping Address: NIST Calibration Services, 100 Bureau Drive, Bldg. 222 Rm B166, Gaithersburg, MD 20899, ATTN: U. Griesmann