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Umbra is the Latin name for “shadow” and is typically used to refer to the shadow cast by an object when illuminated by a light source [2]. In the umbra region of the shadow, the entire light source is occluded by the object. The region around the umbra where only a portion of the light is obscured is called the penumbra [1].
(a) Shadows cast in the case of an object on a surface and (b) shadows cast in the case of an object in free-space
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Encyclopedia Britanicca (2010) http://www.britannica.com/EBchecked/topic/450494/penumbra. Accessed 10 Sept 2010
Encyclopedia Britanicca (2010) http://www.britannica.com/EBchecked/topic/613811/umbra. Accessed 10 Sept 2010
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© 2014 Springer Science+Business Media New York
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Ramanath, R., Drew, M.S. (2014). Penumbra and Umbra. In: Ikeuchi, K. (eds) Computer Vision. Springer, Boston, MA. https://doi.org/10.1007/978-0-387-31439-6_513
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DOI: https://doi.org/10.1007/978-0-387-31439-6_513
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Publisher Name: Springer, Boston, MA
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Online ISBN: 978-0-387-31439-6
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