PASCO OS-8500 INTRODUCTORY OPTICS SYSTEM - Manual (Page 23)

012-02744K Introductory Optics System
®
17
EQUIPMENT NEEDED:
-Optics Bench -Light Source
-Ray Plate and Base -Component Holder
-Slit Plate -Slit Mask
-Cylindrical Lens -Ray Table Component Holder
-Viewing Screen.
Introduction
In this experiment you will look at two phenomena related to refraction: Dispersion and Total
Internal Reflection. Dispersion introduces a complication to the Law of Refraction, which is that
most materials have different indexes of refraction for different colors of light. In Total Internal
Reflection, it is found that in certain circumstances, light striking an interface between two transpar-
ent media can not pass through the interface.
Procedure
Set up the equipment as shown in Figure 6.1, so a single light ray is incident on the curved surface
of the Cylindrical Lens.
Dispersion
Set the Ray Table so the angle of incidence of the ray striking the flat surface of the lens (from
inside the lens) is zero-degrees. Adjust the Ray Table Component Holder so the refracted ray is
visible on the Viewing Screen.
Slowly increase the angle of incidence. As you do, watch the refracted ray on the Viewing
Screen.
➀ At what angle of refraction do you begin to notice color separation in the refracted ray?
Experiment 6: Dispersion and Total Internal Reflection
Figure 6.1 Equipment Setup
90
80 70 60
50
40
30
20
1 0
0
0
10
20
30
4 0
50
60
70
80
90 80 70 60
50
40
30
20
1 0
10
20
30
4 0
50
60
70
80
NOR MAL
NOR MAL
COMPONENT
COMPONENT
Viewing
Screen
Angle of
Incidence