Optical Radiation Measurements Optical Properties of Materials Measurements Rate our Services Technical Contact:
David W. Allen
Tel: 301/975-3680
E-mail: david.allen@nist.gov Please contact the technical staff before shipping instruments or standards to the address listed below. Mailing Address:
National Institute of Standards and Technology
100 Bureau Drive, Stop 8442
Gaithersburg, MD 20899-8442
Fax: 301/840-8551 Service ID
Number | Description of Services | Fee ($) | | 38010C | Spectral Transmittance Filters (Cobalt Blue Glass) | 4906 | | 38020C | Spectral Transmittance Filters (Copper Green Glass) | 4906 | | 38030C | Spectral Transmittance Filters (Carbon Yellow Glass) | 4906 | | 38040C | Spectral Transmittance Filters (Selenium Orange Glass) | 4906 | | 38060S | Special Tests of Spectral Reflectance | At Cost | | 38061S | Special Tests of Spectral Transmittance | At Cost | Fees are subject to change without notice. back to top | back to index of optical radiation measurements This laboratory's quality system is based on the ANSI/NCSL Z540-1-1994 standard and the ISO/IEC Guide 25. NIST supplies to the customer standards of spectral transmittance for checking the photometric scale of spectrophotometers. These are either 30 mm polished glass disks or 51 mm polished glass squares, 2 mm to 3 mm thick, designated as cobalt blue, copper green, carbon yellow, and selenium orange. The relative expanded uncertainty ranges from approximately 0.2 % to 0.3 % of the value. Information provided to the user includes values of transmittance at 25 ° at 10 nm intervals from 380 nm to 770 nm, the estimated uncertainty of each value, and data as to the effect of temperature change on transmittance at each wavelength . back to top | back to index of optical radiation measurements Measurements of spectral reflectance can be made for the wavelength region 250 nm to 2500 nm for neutral, non-fluorescent submitted test items. In general, measurements are performed at room temperature on test items with dimensions from 2 cm to 30 cm perpendicular to the incident beam. Two different measurements are performed of both specular and diffuse reflectance at angles, wavelengths, and polarizations specified by the customer. For the directional-hemispherical geometry incident angles of 0° and 6° are possible, and the later can be measured with the specular component either included or excluded. Uncertainty estimates will be given and will depend on the optical characteristics of the submitted test item and the instrument used to perform the measurement. Arrangements for these measurements on submitted test items must be made before shipment. The decision to perform the measurements and selection of the instruments to be used will rest with NIST. Test items not accepted for measurement will be returned. back to top | back to index of optical radiation measurements Measurements of spectral transmittance can be made at wavelengths from 250 nm to 2500 nm for non-fluorescent submitted test items. In general, measurements are performed at room temperature with the incident beam normal to the front surface of the test item. Items with dimensions from 1 cm to 5.1 cm perpendicular to the incident beam are routinely accommodated. Other sizes and measurement conditions are possible in consultation with NIST staff. Uncertainty estimates will be given and will depend on the optical characteristics of the submitted test item and the instrument used to perform the measurement. Arrangements for these measurements on submitted test items must be made before shipment. The decision to perform the measurements and selection of the instruments to be used will rest with NIST. Test items not accepted for measurement will be returned. back to top | back to index of optical radiation measurements
References-Spectrophotometric Measurements
NIST Measurement Services: Spectral Reflectance , P. Y. Barnes, E. A. Early, and A. C. Parr, Natl. Inst. Stand. Technol. Spec. Publ. 250-8 (revised 1997). NIST High Accuracy Reference Reflectometer-Spectrophotometer , J. Res. Natl. Inst. Stand. Technol. 101(5) 619 (1996). 45 Degrees/0 Degrees Reflectance Factors of Pressed Polytetrafluoroethylene (PTFE) Powder, Natl. Inst. Technol. Stand. Tech. Note 1413 (1995). Compliance in spectrometry:-quality assurance of spectrophotometric measurements at NIST , J. J. Hsia, T. C. Larason, P. Y. Barnes, Spectrophotometry, Luminescence and Coulour; Science & Compl. (1995). Comparison of Regular Transmittance Scales of Four National Standardizing Laboratories , K. L. Eckerle, J. Bastie, J. Zwinkels, V. Saprintsky, and A. Ulyanov, Color Res. Appl. 18 (1), 35-40 (Feb. 1993). International Intercomparison of Regular Transmittance Scales , K. L. Eckerle, E. Sutter, G. H. C. Freeman, G. Andor, and L. Fillinger, Metrologia 27, 33-38 (1990). NBS Measurement Services: Regular Spectral Transmittance , K. L. Eckerle, J. J. Hsia, K. D. Mielenz, and V. R. Weidner, Natl. Bur. Stand. (U.S.), Spec. Publ. 250-6 (July 1987). Establishing a Scale of Directional-Hemispherical Reflectance Factor 1: The Van den Akker Method, W. H. Venable, Jr., J. J. Hsia, and V. R. Weidner, J. Res. Natl. Bur. Stand. (U.S.), 82 (1), 29 (July-Aug. 1977). Permanence of Glass Standards of Spectral Transmittance, K. S. Gibson and M. A. Belknap, J. Res. Natl. Bur. Stand. (U.S.), 44, 463 (May 1950). back to top | back to index of optical radiation measurements Date created: 06/30/1999
Last updated: 01/15/2009 | 