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About
Our Organization
About The IES
Diversity & Inclusion
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IES Staff
IES Board
IES Committees
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Information
Events Home
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Featured Events
IES25 The Lighting Conference
SALC 2025
Special Events
Lightfair 2025
Light for Life® Virtual Symposium
Illumination Awards & Gala
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speed of light
[3.13] (See
Spectral Parameters
.)
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