re·​flec·​tance | \ri-ˈflek-tən(t)s \

Definition of reflectance 

: the fraction of the total radiant flux incident upon a surface that is reflected and that varies according to the wavelength distribution of the incident radiation The basis of this approach is that different materials exhibit unique reflectance and emission properties as a function of wavelength across the electromagnetic spectrum.— Jeffrey Star and John Estes broadly, nontechnically : reflectivity screen reflectance — compare albedo

Examples of reflectance in a Sentence

Recent Examples on the Web

Leica’s attention to detail also extends to the lens hoods for its S-mount lenses, which are covered in a velvety material that’s chosen specifically for its minimal reflectance. Vlad Savov, The Verge, "The Leica S3 is a frustratingly awesome medium format DSLR," 27 Sep. 2018 Plus, the premium nylon lenses are anti-scratch, anti-fog and have anti-reflectance coating. Sarah Sekula, Fox News, "16 Father's Day gifts for the rad dad who loves the outdoors," 7 June 2018 There are algorithms aplenty, geometrical extrusions and something called the bidirectional reflectance distribution function, which is all about understanding the play of light on a surface. Steve Johnson,, "New 'Pixar' exhibit at MSI has Buzz Lightyear and real STEM — and isn't just a booster for the movies," 24 May 2018 The technique, called reflectance hyperspectral imaging, allows scientists to identify minerals based on patterns of dark lines in the spectrum. Kenneth Chang, New York Times, "In Picasso’s Blue Period, Scanners Find Secrets He Painted Over," 20 Feb. 2018 So Hegde and his colleagues are compiling a database of reflectance spectra for different types of microbes. Daniel Clery, Science | AAAS, "Earth-sized alien worlds are out there. Now, astronomers are figuring out how to detect life on them," 1 Nov. 2017 After unearthing the objects, many of which were unbaked and badly worn, researchers used a technique called reflectance transformation imaging, or RTI to take images of the tablets. Rachel Riederer, Smithsonian, "Archaeologists Discover Trove of Cuneiform Tablets in Northern Iraq," 24 Oct. 2017 Her team, including African researchers, used a light meter to measure skin reflectance in 2092 people in Ethiopia, Tanzania, and Botswana. Ann Gibbons, Science | AAAS, "New gene variants reveal the evolution of human skin color," 12 Oct. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'reflectance.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of reflectance

1893, in the meaning defined above

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Last Updated

26 Nov 2018

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Time Traveler for reflectance

The first known use of reflectance was in 1893

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re·​flec·​tance | \ri-ˈflek-tən(t)s \

Medical Definition of reflectance 

: the fraction of the total radiant flux incident upon a surface that is reflected and that varies according to the wavelength distribution of the incident radiation

called also reflection coefficient, reflection factor

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