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.
400 BC – Emission theory of vision
Greek philosopher and mathematician Plato develops the emission theory of vision – we see because our eyes emit straight vision beams.
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.
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.
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.
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.