Encyclopedia of Color Science and Technology

Living Edition
| Editors: Ronnier Luo

Standard Measurement Geometries

  • Bor-Jiunn Wen
Living reference work entry
DOI: https://doi.org/10.1007/978-3-642-27851-8_361-1



Reflectance and transmittance measurements are partly dependent upon the geometry of illumination and viewing. Accordingly, the International Commission on Illumination (CIE) has specified illuminating and viewing conditions, namely, 45°:0°a, 45°:0°c, 45°:0°x, 0°:45°, d:0°, 0°:d, de:8°, and di:8°. With the 45°:0° geometry, the sample is illuminated at an angle of 45° from the normal to the sample surface and viewed normal to the sample surface or within 10° of the normal. There are three standard configurations of the geometry: 45°:0°a, 45°:0°c, and 45°:0°x. The 45°:0°a has a 10° wide cone of light incident on the sample at 45° to the sample normal. The “a” in 45°:0°a indicated “annular,” meaning that the 10° cone continues uninterrupted all the way around the sample. 45°:0°c indicates circumferential illumination, which is similar to annular except that it is distributed in discrete locations around the ring. 45°:0°x...


Inclination Angle Specular Reflection Device Under Test Measurement Geometry Luminous Flux 
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  1. 1.
    Kuhn, R.G.: Color: An Introduction to Practice and Principles. 3rd edn. John Wiley & Sons, Inc. (2012)Google Scholar
  2. 2.
    Fairchild, M.D.: Color Appearance Models. 3rd edn. John Wiley & Sons, Inc. (2013)Google Scholar
  3. 3.
    Wyszecki, G., Stiles, W.S.: Color Science: Concepts and Methods, Quantitative Data and Formulae. 2nd edn. John Wiley & Sons, Inc. (2000)Google Scholar
  4. 4.
    Hunt, R.G.W.: The Reproduction of Colour, 6th edn. John Wiley & Sons, Inc. (2004)Google Scholar
  5. 5.
    SID IDMS Information Display Measurements Standard, v1.03, 1 June 2012Google Scholar
  6. 6.
    SEMI D68-0512: Test Methods for Optical Properties of Electronic Paper Displays (2012)Google Scholar
  7. 7.
    SEMI D56-0310: Measurement Method for Ambient Contrast of Liquid Crystal Displays (2010)Google Scholar

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© Springer Science+Business Media New York 2015

Authors and Affiliations

  1. 1.Department of Mechanical and Mechatronic EngineeringNational Taiwan Ocean UniversityKeelungTaiwan