1. LIGHT BASICS

2. Illumination The human eye can detect changes in size, brightness, position, color of an object. We can tell the difference between shadows and reflections. This is because of illumination.

3. Ray Model of Light Light is represented as a ray that travels in a straight path. The direction can be changed if there is an obstruction.

4. Sources of Light Our major source of Light is the SUN. Another natural source is fire. Light bulbs, TV and computer screens, Lasers, LEDs, are a result of humans using electricity to produce light.

5. Luminous Source An object that emits light. The sun Light bulbs headlights

6. Illuminated source An object that becomes visible as a result of light reflecting off of it. The moon Reflectors

7. Transparent Media Transmit light so that objects can be seen clearly through them Glasses Windows

8. Translucent Media Materials scatter and transmit light so that objects cannot be seen clearly through them. Lamp shade Wax paper

9. Opaque Media Prevent light from passing through them. Brick wall Dark curtain