6A10.20 - Specular & Diffuse Reflection

Code Number:
Demo Title:
Specular & Diffuse Reflection
Area of Study:
Point Source Lamp, CD's with Figures on the Labels, and Tracing Paper Screen.

Place the CD's on the table label side up and point the lamp down on them.  Place the tracing paper screen so that it catches the reflection from the CD.  Those portions of the label that can be read on the screen are due to the specular reflection, and those that are very blurry, or can not be read at all are due to the diffuse reflection.

  • Kensei Yasuda, Alvin Kim, Hayley Cho, Timofej Timofejev, Wojciech J. Walecki, James Klep, Amy S. Edelson, Abigail S. Walecki, Eve S. Walecki, and Peter S. Walecki, "Specular Reflection from Rough Surfaces Revisited", TPT, Vol. 54, #7, Oct. 2016, p. 394.
  • Joshua M. Grossman, "Vampire Selfie: A Curious Case of an Absent Reflection", TPT, Vol. 52, #8, Nov. 2014, p. 458.
  • Hassan Mohammadpour, "Look Around to Learn Physics", TPT, Vol. 46, #3, Mar. 2008, p. 158.
  • Jay M. Pasachoff, "Grazing Incidence Reflection and X-ray Images", TPT, Vol. 41, #4, Sept. 2003, p. 318.
  • Hasan Fakhruddin, "Specular Reflection from a Rough Surface", TPT, Vol. 41, #4, Apr. 2003, p. 206.
  • Frank Kowalski, "Reflectance Demonstration", TPT, Vol. 31, #3, Mar. 1993, p. 153.
  • Edward W. Stark, "Diffuse Reflection: Uses That Affect Our Lives", TPT, Vol. 24, #3, Mar. 1986, p. 144.
  • Gerald S. Birth, "Diffuse Reflection", TPT, Vol. 24, #3, Mar. 1986, p. 138.
  • Chris D. Zafiratos and John C. Groft, "A Black Surface Fabrication from Specular Reflectors", TPT, Vol. 20, #5, May 1982, p. 316.
  • Ron Hipschman, "Recipe No. 165: Color Table, Exploratorium Cookbook III, p. 165-1 - 165-3.

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