Light and Optical Systems: Reflection, Refraction, and Devices

Light (Theory From Pythagoras)

Consists of beams that come from a person's eyes when these beams touch the objects.

Newton's Light Experiment

Newton passed a beam of sunlight through a glass prism, breaking white light into seven colors.

Properties of Light

1. Light travels in straight lines. 2. Light can be reflected (bounce back). 3. Light can bend (refract). 4. Light is a form of energy.

Optical Device

Any technology that uses light.

Microscope

Uses lenses (at least 2) to create an enlarged image of a tiny object.

Telescope

Provides enlarged images of far objects by using lenses and mirrors to collect light and bring it to your eyes. Made by Galileo

Types of Telescopes

Refracting Telescope and Reflecting Telescope

Ray Diagrams

Shows how light travels in straight lines called rays.

Shadows

Lack of light on an object when light cannot reach it.

Transparent Materials

Materials that light travels straight through.

Translucent Materials

Materials that allow some but not all light to pass through.

Opaque Materials

Materials that do not allow light to pass through.

Luminous

Produces light (e.g., sunlight, bulb).

Non-luminous

Does not produce light (e.g., duck, pencil).

Regular Reflection

When light rays hit a smooth surface and bounce off parallel to each other.

Diffuse Reflection

When light hits a rough surface and is reflected in different directions.

Law of Reflection

Angle of incidence is equal to the angle of reflection.

Incident Ray

Ray of light that strikes a surface; comes directly from the light source.

Reflected Ray

Ray that bounces off the surface.

Concave Mirror

Has a surface that curves inward like a bowl, collecting light.

Focal Point

Common point where light rays reflect after hitting a concave mirror.

Convex Mirror

Has a surface that curves outward, spreading out light.

Refraction

When light travels at an angle from one substance to another and bends.

Concave Lens

Has a surface that curves inward; light rays spread out.

Convex Lens

Has a surface that curves outward; light rays may collect.

Refracting Telescope

uses 2 lenses to gather and focus light

Reflecting Telescope

uses mirrors to gather and focus light.

Light (Theory from al-Haytham)

Light bounces off objects and then travels to the eyes showing that light does not come from the eyes, but rather light travels to the eyes