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©1990-2002 J.Paul Robinson, Purdue University
Some
Definitions
•Absorption
–When light passes through an object the intensity is
reduced depending upon the color
absorbed. Thus the selective absorption
of white light produces colored light.
•Refraction
–Direction change of a ray of light passing from one
transparent medium to another with
different optical density. A ray from less to more dense medium is bent perpendicular to the surface, with greater deviation for shorter
wavelengths
•Diffraction
–Light rays bend around edges - new wavefronts are
generated at sharp edges - the
smaller the aperture the lower the definition
•Dispersion
–Separation of light into its constituent wavelengths
when entering a transparent
medium - the change of refractive index with wavelength, such as the spectrum produced by a
prism or a rainbow
