Light Main Page

Mankind has been interested in, and has studied, light for a long time.

Light is necessary for life as we know it to exist on the planet.  Our main light source is the sun.

Plants take the light energy from the sun and convert it into chemical energy by a process known as photosynthesis.

As long ago as about 1000 AD someone proposed that light was made up of very tiny particles that came from the source of the light.

In 1670 Christian Huygens explained some of the many properties of light by suggesting that light was like a wave. Later in 1801 Thomas young provided more evidence for light being like a wave by demonstrating interference between rays of light.  Maxwell came up with a theory in 1865 that electromagnetic waves travel at the speed of light.  Max Planck and Albert Einstein added to our knowledge of light during the 20th century.

We now know that light has both wave-like and particle-like properties.

Terms used in the study of light.

Angle of deviation, Angle of incidence, Angle of reflection, Angle of refraction, Corpuscles, Critical angle,  Diffraction, Diffuse refraction, Dispersion, Electricity, Electromagnetic wave, Fiber Optics, Frequency, Huygen's Principle,  Interference, Internal reflection, Magnetism, Normal. Photoelectric effect, Photons, Planck's constant, Prism, Prism spectrometer, Quanta, Rainbow, Ray, Ray approximation, Refraction, Reflection, Retroreflection, Snell's Law of refraction, Spectrum, Specular refraction, Speed of light, Total internal reflection, Visible light, Visible spectrum, Wave, Wave front, Wavelength,