History of Discovery in Light and Vision

1. Euclid was an ancient Greek most noted for his contributions to geometry. He did contribute much to physics and light as well however. Euclid built off of Empedocles ideas and had the single greatest break through in light and vision history. He asked the question, Why do objects that are far seem so much smaller than they actually are? Through his studies, Euclid determined taht rays from the eyes must follow straight lines; rays of light travel in straight lines.

2. Empedocles was a Sicilian philosopher, doctor, and poet. He believed that we see objects because light streams out of our eyes towards them. An interesting story about Empedocles is that he threw himself into the volcano a Mount Etna in Sicily, in an attempt to prove that he was immortal. Unfortunately for Empedocles however, he was not immortal, and he died.

3. When Sicily fell to the rule of Islam, Islamic scholars translated, edited, and debated the optical and light ideas of the Greeks. al-Haytham was one of the leading scholars who worked with the ideas of the Greeks. He ultimately discovered how light and vision worked. He worked for al-Hakim, a powerful lord who encouraged learning because he wanted to control everything. He ordered al-Haytham to stop the Nile from flooding. But al-Haytham knew that this was impossible, so he pretened to be crazy to get out of the task. It didn't work however; he was thrown into jail. While in captivity, he bcame obsessed with light and dark. He refuted Empedocles ideas that rays come out of the human eye, because he realized that when he stared at the sun, his eyes hurt. This would not happen if rays came from the eyes. While in jail he studied light with the help of mirrors, and realized that light bounces like a ball. He said that rays travel through space in straight lines to our eyes. He ultimately estblished the laws of reflection and refraction. al-Haytham's works inspired future scientists like Roger Bacon, who built off his ideas about vision.

4. Roger Bacon was a 13th Century Fransiscan Friar who studied the al-Haytham's works. He studied the effect of light on glass and colors. He had a breakthrough when he realized that curved glassses can change the appearance of objects. This led to enhancement in spectacles. Roger Bacon was also obsessed with the rainbow, but his obsession borders on heresy. The rainbow represents an intense relationship between believers and god, and Bacon's work to replicate rainbows angered many religious people. Bacon was able to explain the miracle of the rainbow through natural law. He figured out that rainbows are a result of reflection and refraction in individual droplets of water. This discovery was religious suicide for Bacon. he was exiled for his works and placed in closed confinement in Paris.