Experiment 10: polarization – PASCO OS-8500 INTRODUCTORY OPTICS SYSTEM User Manual

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Introductory Optics System

EQUIPMENT NEEDED:

-Optical Bench

-Light Source

-Polarizers (2)

-Component Holders (3)

-Ray Table and Base

-Ray Table Component Holder

-Cylindrical Lens

-Crossed Arrow Target

-Slit Plate

-Slit Mask.

Experiment 10: Polarization

Figure 10.1 Polarization of Light

Introduction

Light is a transverse wave; that is, the electromagnetic disturbances that compose light occur in a direc-
tion perpendicular to the direction of propagation (see Figure 10.1a). Polarization, for light, refers to the
orientation of the electric field in the electromagnetic disturbance. The magnetic field is always perpen-
dicular to the electric field. Figure 10.1b and 10.1c show vertical and horizontal polarization, respec-
tively. Figure 10.1d depicts random polarization, which occurs when the direction of polarization
changes rapidly with time, as it does in the light from most incandescent light sources.

Your optics equipment includes two Polarizers, which transmit only light that is plane polarized along
the plane defined by the 0 and 180 degree marks on the Polarizer scales. Light that is polarized along
any other plane is absorbed by the polaroid material. Therefore, if randomly polarized light enters the
Polarizer, the light that passes through is plane polarized. In this experiment, you will use the Polarizers
to investigate the phenomena of polarized light.

Figure 10.2 Equipment Setup

(a)

(b)

(c)

(d)

90˚

_
B (magnetic Field)

_
n (direction of
propagation)

_
E (Electric Field)

Crossed Arrow Target

Polarizer B

Polarizer A