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Light and Optics

  1. The Spectrum
    • Continuous Spectrum Spectrum production using prism and carbon arc or slide projector. (m/l) (T+) ***
    • Spectrum Recombination. A second prism recombines the colors to produce white light; alternatively, colors may be recombined in a glass globe. (m/l) (T+)
    • Complementary Spectrum. A complementary (opaque) slit produces the the complementary colors of the regular spectrum. (l) (T+)
    • Ultra-Violet Radiation. Carbon arc with quartz optics and fluoroscopic screen. (m/l) (T+)
    • Radiometer Detection of IR radiation from hair dryer and/or special IR source. (m) (T) **
    • Infra-Red Radiation. Carbon arc with six thermometers or radiometer positioned through spectrum. (m/l) (T++)
    • Infra-Red Projector Lantern projector with IR transmission filter and heat sensitive liquid crystal screen. (m) (T+) **
    • Infra-Red Beam. Electric heater with parabolic mirror; a second parabolic mirror focuses IR beam (with flash paper detection). (m) (T+)
    • Bursting Balloon The blue light of an argon laser bursts a red, but not blue, balloon; the red balloon may be inside a clear balloon. (l) (T++) ***
    • Monochromatic Illumination. Students are asked to guess the colors of various objects illuminated by monochromatic light from a carbon arc spectrum. (l) (T+)
    • Gray Scale Perception A demonstration of eye/brain logic in the perception of gray scales across boundaries using rotating disks and/or cylinders. (m) (T+)
    • Color That Isn't There. Subjective colors appear when observing rapidly alternating patterns of black and white on a spinning disk. (s/m) (T+)
    • Color Mixing Additive color mixing with three slide projectors and filters. (l) (T+) **
    • TV Color Perception RGB additive color mixing shown by magnified phosphor dots of video monitor. (l) (T++) ****
  2. Geometrical Optics; Light Rays and Reflections
    • Ray Vector Block. A model of the incident and reflected rays w.r.t. the normal. (s) (T)
    • Blackboard Optics Mobile ray-tracing kit to demonstrate basic geometrical optics. (l) (T) ***
    • Optics Disk Angle of incidence = angle of reflection clearly demonstrated. (m) (T) ***
    • Electronic Pinhole Camera TV camera with lens replaced by pinhole in foil. (m) (T+) ***
    • Inverse Pinhole Camera. A pinhole projector to demonstrate various aspects of image formation. (l) (T++)
    • Inverse Square Law Large climbing frame shaped to show inverse square relation of light intensity (smaller version also available). (xl) (T+++)
    • Hero's Shortest Path A string and pulley model to demonstrate Hero's explanation of why the angles of reflection and incidence are equal. (m) (T+) **
    • Glass Transmission/Reflection. Show the percentage of transmitted and reflected light. (s) (T++)
    • Spherical Mirror Imaging. Produce real and virtual images with a large mirror. (l) (T++)
    • Mirage Mirror Dual spherical mirrors produce a mirage. (s) (T+)
  3. Geometrical Optics; Refraction and Dispersion
    • Blackboard Optics Mobile ray-tracing kit to demonstrate basic geometrical optics. (l) (T) ***
    • Microscope and Telescope Optics. Long and short focal length lenses are arranged on an optics rail to model these two optical instruments. (m) (T+)
    • Relative Indices of Refraction. A lens, immersed in a fish tank of water, seemingly loses its refractive powers to focus light. (m) (T+)
    • Disappearing Prism Immersion of quartz prism in water/glycerine solution of equal refractive index. (s) (T+) ***
    • Wheel and Axle Wavefront Mechanical analog/simulation of wavefront at boundary between two mediums. (l) (T+) *
    • Florence's Rainbow A rainbow is produced with a water-filled Florence flask; with monochromatic illumination, this becomes Descartes' rainbow. (l)(T+) **
    • Giant Raindrop. Large water-filled plastic raindrop shows, by laser ray tracing, the opticsof rainbow making. (m) (T+)
    • Dispersion. Prism and white light; second prism shows no further dispersion. (m) (T+)
    • Achromatic Prism. Refraction without dispersion! (m) (T+)
    • Hotplate Mirage Laser beam is refracted up when a hotplate is positioned below it. (m/l) (T+) **
    • Hot Road Mirage Viewing down a heated model roadway produces a mirage. (m/l) (T+) ***
    • Schlieren Optics Temperature variations in the index of refraction of air are dramatically demonstrated. (l) (T+++) ****
    • Bouncing Lightbeam Long tank with sugar solution forming refractive index gradient; laser beam bounces down the tank by total internal reflection/refraction. (m) (T++) ***
    • Real and Virtual Images. Formation of images using lenses. (m) (T+)
    • Refraction of Microwaves. 10 cm microwaves refracted through wax prism. (l) (T++)
    • Critical Angle. Optics disk ensemble using plastic semi circle. (l) (T)
    • Fishtank TIR Laser beam reflected off underside surface of water in tank. (m) (T+) *
    • Fibre Optics Fibre optic strands and clear plastic rods transmit laser light (m) (T) **
    • Bucket of Light Stream of water transmits laser light as it arcs into a bucket.  (m) (T+) ****
    • Frustrated Total Internal Reflection To reflect or not to reflect at the interface of two prisms in intimate contact? That is the question. (m) (T+) **
  4. Interference and Diffraction
    • Newton's Rings Circular interference pattern formed between spherical and flat glass plates. (s) (T++) ***
    • Thin Film Interference Interference patterns on soap films or oil slick. (m) (T+) ****
    • Gold Mirror. Thin gold-film interference selects spectral bandwidth. (m) (T+)
    • Michelson Interferometer The classic application of spatial coherence lengths. (s) (T+) ***
    • Fabry-Perot Etalon. The most common multiple-beam interferometer. (s) (T++)
    • Hear the Wall Bend A room size laser interferometer with audio signal output. (l) (T+)
    • Adjustable Single Slit. Diffraction pattern changes with slit aperture. (m/l) (T++)
    • Slit Diffraction. Single or multiple slit diffraction patterns with laser. (m/l) (T++)
    • Edge Diffraction Schlieren optics is used to demonstrate the diffraction of light around objects (l) (T+++); more simply done with razor blade and laser or white light source. (l) (T+) **
    • Diffraction Gratings. Hand held transmission gratings or large reflection grating. (m) (T)
    • Two-Dimensional Interference. Various two-dim gratings, apertures, Fresnel zone plates, opaque objects, and edges. (m/l) (T+)
    • Laue Optical Analog. 2-Dim interfernce pattern as optical analog of x-ray diffraction; spinning the grating simulates polycrystaline ring patterns. (l) (T)
    • Laser Diffraction Off Ruler. Machinist's scale used as reflective grating. (m) (T+)
    • Single Photon Interference Young's double slit experiment with camera/detector sensitive to single photons. (l) (T+++) ****
    • Poisson's Spot. Bright spot in center of shadow of ball bearing caused by diffraction of incident laser light. (l) (T++)
    • Microwave Interference. Young's double slit interference using microwaves. (l) (T++)
  5. Resolution
    • Adjustable Single Slit. Example of detector aperture effect. (l) (T+)
    • Airy's Disc. Circular aperture effect. (l) (T+)
    • Rayleigh's Criterion Variable width slit shows dependance of aperture size on resolution of two closely aligned lasers. (l) (T++) **
    • Telescope Resolution. An adjustable aperture in front of a telephoto lens is closed down to show the Rayleigh limit. (l) (T++)
    • Fresnel Diffraction. The optical limits of a microscope are demonstrated as one attempts to resolve 1 mm diameter spheres. (l) (T++)
  6. Polarization and Scattering
    • Brewster's Angle Reflected light from spot lamp is tested for degree of polarization as a function of angle of reflection. (l) (T+) **
    • Polarization by Scattering Light from slide projector scattered and polarized as it passes through aquarium containing milky water. (m) (T+) ***
    • Mie Scattering. Wavelength and angular dependence of the intensity of light scattered from micron size spheres is observed in an aquarium. (m) (T+)
    • Double Refraction Transmitted light split into two polarized rays by calcite crystal. (s)(T) ***
    • Polarization by Absorption Polaroid filters are used to polarize as well as analyze light. (m) (T) **
    • Malus' Law Two Polaroid filters are used to show cos2(f) dependence of transmitted intensity. (m) (T) ***
    • Photoelasticity Stress patterns in transparent plastic revealed when placed between two crossed Polaroid filters on OHP. (m) (T) ***
    • Circular Polarization Circular polarization produced by linear polarizer, 1/4 wave retardation, and reflection from mirror. (s) (T+) **
    • Sugar Syrups OHP polarimeter reveals circular polarization of sugar syrups. (s) (T+) **
    • Syrup Tube A 6-ft long glass tube filled with Karo syrup rotates the polarization dozens of times. (m) (T+) ***