Gelatin Optic Fibers

Source Institutions

Source Institutions

Add to list Go to activity
In this activity, learners make optical fibers out of strips of gelatin. The boundary surface between the gelatin walls and air acts like a mirrored surface, reflecting the light as if it were bouncing off a mirrored surface. As a result, shining the laser pointer through the gelatin strips demonstrates total internal reflection. Try changing the direction of the laser pointer and see what happens. Educators can use this activity to demonstrate refraction and critical angles. Note: learning time includes the time it takes to make and refrigerate the gelatin. [Activity is publicly available through a web crawler capture on]

Quick Guide

Preparation Time:
Under 5 minutes

Learning Time:
2 to 4 hours

Estimated Materials Cost:
$1 - $5 per group of students

Age Range:
Ages 8 - 14

Resource Types:
Activity, Demonstration


Materials List (per group of students)

  • inexpensive laser pointer
  • package of unflavored or light-colored gelatin dessert
  • shallow cake pan
  • spatula
  • mixing bowl
  • ruler


  • Engineering and Technology
    • Engineering
      • Electrical Engineering
      • Metallurgy and Materials Engineering
  • Physical Sciences
    • Vibration and Waves
      • Light and Optics
    • Light and Optics
      • Lasers
      • Lenses and Mirrors
      • Reflection and Refraction

Informal Categories

  • Electronics
  • Food and Cooking


To use this activity, learners need to:

  • see
  • see color
  • touch

Learning styles supported:

  • Involves hands-on or lab activities


Access Rights:

  • Free access



Funding Source:

  • 3M