Prisms, total internal reflection, polarization, how we see color, how vision is corrected and rainbows.

Prisms High frequency light in a transparent medium travels slower than low frequency light (red light travels faster than violet light) Thus, the different colors are refracted at different angles. When white light is refracted twice, and the second surface is not parallel to the first, the dispersion is noticeable, thus the colors are observed. If the two boundaries of the medium are parallel, the refractive effects at the first boundary are reversed at the second boundary.

Total Internal Reflection Light can be reflected off a transparent medium boundary at a certain angle. This angle is called the critical angle.                   Fiber Optics

Optical Fibers 29.12 Total Internal Reflection Optical fibers, sometimes called light pipes, are transparent fibers that pipe light from one place to another. They do this by a series of total internal reflections. Optical fibers are useful for getting light to inaccessible places. Mechanics and machinists use them to look at the interiors of engines, and physicians use them to look inside a patient’s body. 4

Total Internal Reflection

Total Internal Reflection http://www.phy.ntnu.edu.tw/java/optics/path_e.html http://micro.magnet.fsu.edu/primer/java/refraction/criticalangle/index.html

Polarization of Light Light consists of waves vibrating in all planes (360o). A polarizer allows only the light wave along one plane to pass through. Two polarizers if oriented at right angles will cancel all light. Glare (reflected light polarized in a plane parallel to a non-metallic surface) is greatly reduced when using polarized lenses. http://lectureonline.cl.msu.edu/~mmp/kap24/polarizers/Polarizer.htm

28.1 The Color Spectrum When sunlight passes through a prism, it separates into a spectrum of all the colors of the rainbow. roygbiv

Isaac Newton—discovered that white light is composed of seven different colors of light Dispersion of white light into component colors Red Orange Yellow Green Blue Violet White Light A prism disperses white light into its primary frequencies of color

http://hyperphysics.phy-astr.gsu.edu/hbase/ems3.html R Nave

Prisms http://www.physics.mun.ca/~jjerrett/dispersion/prism.html http://micro.magnet.fsu.edu/primer/java/prism/index.html

Rainbows, etc. http://mysite.verizon.net/vzeoacw1/rainbow.html http://micro.magnet.fsu.edu/primer/java/refraction/refractionangles/index.html

Refraction http://freespace.virgin.net/gareth.james/virtual/Optics/Refraction/refraction.html http://www.physicsclassroom.com/Class/refrn/u14l1f.html

http://acept. la. asu. edu/PiN/mod/light/opticsnature/pattLight4Obj1 http://acept.la.asu.edu/PiN/mod/light/opticsnature/pattLight4Obj1.html http://www.wrh.noaa.gov/Flagstaff/science/skyblue.htm http://www.cordonline.net/laserapplets/