The intensity of high-order rainbows for normally incident light and certain rotation angles of a cylinder with an elliptical cross section is greatly amplified with respect to the intensity for a circular cross-sectional cylinder. The amplification is due to a number of the internal reflections occurring past the critical angle for total internal reflection, and the effect is especially strong for odd-order rainbows, beginning with the third order. Experimentally, the fourth-and the fifth-order rainbows of a nearly elliptical cross-sectional glass rod were observed and analyzed. (C) 1998 Optical Society of America.
Lock, James A.; Adler, Charles L.; Stone, Bradley R.; and Zajak, Patrick D., "Amplification of High-Order Rainbows of a Cylinder with an Elliptical Cross Section" (1998). Physics Faculty Publications. 74.
Lock, James A., Charles L. Adler, Bradley R. Stone, and Patrick D. Zajak. "Amplification of High-Order Rainbows of a Cylinder with an Elliptical Cross Section." Applied Optics 37 (1998): 1527-1533.
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