8/13/2019 9 Vision Phys

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Lecture: Physiology of Vision

I. Overview of Light and Optics

A. Wavelength and Colors of Visible Radiation

1. electroagnetic radiation

gaa ra!s "#ra!s $V light VISIBLE LIGHT Infrared Radio Wave

short ediu long%1'n( %)*+'& n( %1&,n(

,. wave#photon dualit! # light travels in wave#li-e fashion with single pac-etsof energ! called photons

). visible spectru # different colors of light have different wavelengths

Violet /lue 0reen ellow Orange Red

)*&n 2*&n ''&n 3)&n 3*&n +)&n

2. color of an ob4ect # the color of an ob4ect is deterined b! which

wavelengths are R56L5C758 bac- to the retina %not absorbed b! the ob4ect(

a. white # all wavelengths reflected b! ob4ect

b. blac- # all wavelengths absorbed b! ob4ect

/. Refraction of Light and Conve9 Lenses

1. light refraction # light will bend when it passes fro one ediu %air(into another %lens( e.g. pencil in glass of water

,. conve9 lens # %thic-er at center tapered at edge( causes light to bend sothat it coes together at a focal point

a. real iage # iage at focal point of conve9 lens ###; inverted