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Light ideas and technology – timeline

This timeline provides a look at some of the key advances in ideas about light, how we see and how we perceive the world around us.

300 BC – First writings about reflection and refraction

Greek mathematician Euclid writes Optica. He asserts that light travels in straight lines and proposes mathematical formulae for reflection and refraction.

160 AD – Ptolemy and refraction

Roman astronomer Ptolemy writes about the refraction of light and further develops the emission theory of vision – objects are seen by rays of light emanating from the eyes.

984 – Ibn Sahl and refraction

Persian scientist Ibn Sahl writes On burning mirrors and lenses, which sets out his understanding of how curved mirrors and lenses bend and focus light. He discovers a law of refraction mathematically equivalent to Snell’s law (1615).

1021 – Intromissionist theory

Arab scientist Ibn al-Haytham contends that vision occurs because of rays entering the eye (intromissionist theory). He also contends that magnification is due to refraction, and he makes the link between glass curvature and magnification.

Cover page for 'Book of Optics' by Arab scholar Ibn al-Haytham

Cover page for Book of Optics

This is a seven-volume treatise on optics and other fields of study by the medieval Arab scholar Ibn al-Haytham, (965– c. 1040 AD).

1250 – Roger Bacon and reflection

English philosopher Roger Bacon uses parts of glass spheres as magnifying glasses and discovers that light reflects from objects rather than being released from them.

1604 – How the eye focuses light

German mathematician and astronomer Johannes Kepler describes how the eye focuses light and specifies the laws of rectilinear propagation of light.

1615 – Snell’s law

Snell’s law (named after Dutch astronomer Willebrord Snellius but first accurately described by Ibn Sahl in 984) describes the relationship between the angles of incidence and refraction when referring to light passing through a boundary between two different media.

1668 – Corpuscular theory expanded

Isaac Newton expands the theory originally set forward by Pierre Gassendi that light is made up of small discrete particles called ‘corpuscles’ to claim that light is made up of different parts.

Statue of Sir Isaac Newton at Trinty College Chapel, Cambridge.

Statue of Sir Isaac Newton

Sir Isaac Newton (1643–1726) entered Cambridge University in 1661. He was elected a Fellow of Trinity College in 1667 and Lucasian Professor of Mathematics in 1669. He remained at the university, lecturing in most years, until 1696.

1672 – Colours explained

Isaac Newton demonstrates how white light can be separated into a spectrum of colours with a prism. He develops ideas about different colours of light being absorbed, transmitted or reflected. His book Opticks is released to the public in 1704.

1678 – Wave theory

Dutch physicist Christiaan Huygens argues that light consists of waves and uses this theory to explain double refraction. Thomas Young’s experiments (1801) support Huygens’s wave theory.

1860 – Electromagnetic field

James Clerk Maxwell explains that electricity, magnetism and light are all manifestations of the same phenomenon – the electromagnetic field.

1899 – Planck’s theory

Max Planck models black body radiation by assuming that the exchange of energy between light and matter only occurs in discrete amounts he called quanta.

1905 – Interpretation of the photoelectric effect

Albert Einstein publishes a mathematical description of the photoelectric effect. This establishes that light consists of particles or ‘discrete quanta’. These particles later became known as photons.

The photoelectric effect

University of Waikato science researcher Dr Adrian Dorrington explains the photoelectric effect. He then describes how camera sensors can be designed on the basis of this effect to enable light energy to be converted into electric potential energy. Each sensor is split up into an array of pixels so each pixel has a storage area.

Rights: University of Waikato. All Rights Reserved.

1922 – First 3D movies

William Friese-Greene files a patent for a 3D movie process in the late 1890s, Louis Ducos du Hauron invents red and blue glasses for 3D in 1915, and the first public 3D movie is screened in 1922.

1925 – First television

John Logie Baird demonstrates the first operating television system in London.

1960 – First working laser

Theodore Maiman produces the first working laser. A laser has the ability to generate an intense, very narrow beam of light of a single wavelength.

2010 – 3D televisions

The first full 3D TVs with use of shutter technology become available.

3D technology

Dr Adrian Dorrington, a scientist from the University of Waikato, explains the basic concept behind 3D television and film. One system requires the viewer to wear active glasses so that the right image is delivered to the right eye at the right time. Active glasses require a power source to operate the shutter system in the lenses.

Rights: University of Waikato. All Rights Reserved.

 

Published:14 March 2012