sir david brewster
Scottish physicist noted for his experimental work in optics and polarized light-i.e., light in which all waves lie in the same plane. When light strikes a reflective surface at a certain angle (called the polarizing angle), the reflected light becomes completely polarized. Brewster discovered a simple mathematical relationship between the polarizing angle and the refractive index of the reflective substance. This law is useful in determining the refractive index of materials that are opaque or available only in small samples.
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