"Is Diffraction actually Reflection?"

by Ted Huntington


In the 1600s Francesco Grimaldi invented the term “diffraction” to describe what he thought was light “bending” around corners to display bands of colored light. Newton referred to this phenomenon as “inflexion”. But some scientists of the 1700s thought that this phenomenon of diffraction might be explained by light reflection from the inside of the slit. Even now we still refer to “diffraction gratings”, but might it be more accurate to call these gratings “reflection gratings”? A computer simulation of the failed “corpuscular” interpretation of Francesco Grimaldi’s “diffraction” experiment explores the theory that particle “reflection” might be responsible for the various orders of light observed in such experiments. In this model, the “orders” apparent in the pattern of light projected through a thin slit, are theorized to be due to reflected particles, where the order n=0 are unreflected particles, n=1 are once-reflected particles, n=2 are twice-reflected particles, and so on.

(3D videos of supposed "diffraction" as actual "particle reflection" model):
(Note that the particle color change represents how many times a particle has been reflected.)

Citing this article:
Ted Huntington, "Is Diffraction actually Reflection?", 06/10/2008.
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