6J10.80 - Optical Resolution - Resolving Power

Code Number:
Demo Title:
Optical Resolution - Resolving Power
Resolving Power
Area of Study:
Two small Mag light type flashlights.

Video Credit: Jonathan M. Sullivan-Wood.

Take the focusing caps of the flashlights and place the glowing lamps as close together as possible.  Those closest to the lamps will still be able to see two spots, but those farther away will only see one spot.

  • Cyril Carbonel, Sebastien Grasset, Jean Maysonnave, "Accessing High Spatial Resolution in Astronomy Using Interference Methods", TPT, Vol. 56, #4, Apr. 2018, p. 232.
  • Cark E. Mungan, "Approximation for the Rayleigh Resolution of a Circular Aperture", TPT, Vol. 47, #5, May 2009, p. 288.
  • Steve Kreis, "Megapixels and Human Recognition of Resolution", TPT, Vol. 46, #5, May 2008, p. 304.
  • Daniel A. Dale and Brenae L. Bailey, "Physics in the Art Museum", TPT, Vol. 41, #2, Feb. 2003, p. 82.
  • Micheal J. Ruiz, "Visual Acuity Revisited", TPT, Vol. 18, #8, Nov. 1980, p. 560, also A Potpourri of Physics Teaching Ideas - Optics and Waves, p. 218.
  • Micheal J. Ruiz, "The Physics of Visual Acuity", TPT, Vol. 18, #6, Sept. 1980, p. 457, also A Potpourri of Physics Teaching Ideas - Optics and Waves, p. 217.
  • Thomas Leo Rokoske, "Poor Man's PSSC Resolution Experiment", TPT, Reprints from April 1963 - December 1971, p. 136.
  • Haym Kruglak, "Another Legend Debunked", AJP, Vol. 28, #7, Oct. 1990, p. 491.
  • Mario Iona, "Resolution Determined By Aperture", TPT, Vol. 20, #7, Oct. 1982, p. 484.
  • Clarence H. Annett, "Optical Resolution Demonstrated By Flashing Lights", TPT, Vol. 20, #5, May 1982, p. 336.
  • Costantino Sigismondi, "Measuring the Angular Solar Diameter Using Two Pinholes", AJP, Vol. 70, #11, Nov. 2002, p. 1157.
  • Wolfgang Rueckner, Costas Papaliolios, "How to Beat the Rayleigh Resolution Limit: A Lecture Demonstration", AJP, Vol. 70, #6, June 2002, p. 587.
  • Carol L. Miles, "The Measurement of Resolution of a Slit-Limited Eye", AJP, Vol. 58, #6, June 1990, p. 552.
  • H. W. White, P. E. Chumbley, R. L. Berney, and V. H. Barredo, "Undergraduate Laboratory Experiment to Measure the Threshold of Vision", AJP, Vol. 50, #5, p. 448, May 1982.
  • Haym Kruglak, "Limit of Eye Resolution with Slitfilm", AJP, Vol. 49, #12, Dec. 1981, p. 1183.
  • Wallace A. Hilton, "G-1", Experiments in Optical Physics, p. 6.
  • O-005: "Sources-Apertures-Projection", DICK and RAE Physics Demo Notebook.
  • O-570: "Eye Viewing Two Dots", DICK and RAE Physics Demo Notebook.

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