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When I started studying color to understand harmony and color systems, I also dug into the history of light, color and vision. I wrote a small recap of this history as an appendix for my first paper Notes on the RGB Color Space. This article contains that text.

Nature of Light and Color

Light has been subject of captivation and study to philosophers and physicists since the times of Aristotle and Theophrastus; their observations concluded that light was colorless and it was due its interaction with matter that acquired different colors.

This conception of light remained valid until Isaac Newton’s experiments with white light passing through prisms proved that colors are part of light and the prism was just causing them to split (Newton, 1704). From his observations, he explained that the particles composing light traveled at different speeds through the prism causing the different colors of light.

Almost half a century later in his work on optics, Leonhard Euler proposed that the phenomena of color diffraction (the split of light into its different colors) could be explained easier if light was understood as a wave rather than a particle (Euler, 1746).
The ideas of Euler and Newton prevailed in the table until Thomas Young (Young, 1804) and Augustin-Jean Fresnel (Fresnel, 1817) through independent experimentations, confirmed that color was the visible manifestation of light’s wavelength overcoming Newton’s proposition of light as a particle.

The final addition to this era’s conception of light, was the first approximated calculation of the speed of light made by Leon Foucault (Foucault, 1850), supporting the wave theory. These ideas and concepts would remain valid until the quantum theory of light in the 20th century.

Human Vision

Along with the understanding of the nature of light and color, different theories about how the humans see light and color were proposed as well. Starting with Thomas Young (Young, 1802) in his work on optics he postulated that the human eye was capable of perceiving particular ranges of visible light through three photoreceptors located in the eye (today known as cone cells).

Hermann von Helmholtz (Helmholtz, 1850), extending Young’s theories, found that the three types of photoreceptors could be classified as short-preferring (perceiving blue), mid-preferring (perceiving green) and long-preferring (perceiving red) depending on the different wavelengths of light received by the retina.

In conjunction, the different strengths of the signals detected by the photoreceptors are interpreted by the brain as a visible color. These two findings are included in what we know today as the Young-Helmholtz theory.

On another line of research, Ewald Hering (Hering, 1892) proposed what became the System of Color Opponency, which establishes that the eye has three couples of receptors perceiving opponent colors: red-green, yellow-blue and white-black.

In his studies on colorimetry, Erwin Schrödinger (Schrödinger, 1920) proved the mathematical equivalence of both models: Young-Helmholtz and Color Opponency.

Interestingly, today we know that color is not an intrinsic property of matter but a combination of different light phenomena that triggers a sensation in the brain (that we identify as color) as a result of the stimulation of the color-sensors in the eyes as described in the human vision theories above.

Commission Internationale de l’Eclairage

The International Commission on Illumination (abbreviated CIE from its french name) is the international authority on light, color and illumination.

Although the commission was officially established in 1913, it was during the International Gas Congress held in Paris in 1900 when the Prof. T Vautier, then president of the Societé Technique de l’Industrie de Gaz de France, on his opening speech referred to the desirability for a general agreement on methods of measuring the light given by incandescent gas lamps and the need for an International Commission in charge of seeing over these agreements.

The resolution was adopted unanimously followed by the creation of the Commission Internationale de Photométrie (CIP) which held its first session was in Zurich in 1903. During this first meeting, five papers were presented to discuss, among other topics, the relative luminous intensities of the various flame standards then in use, becoming the most relevant topic for the following years and subsequent sessions of the CIP.

With the rapid development of illuminating engineering, multiple societies in different countries were created to foster the progress of these new technology. In 1911 (and a few weeks after the third session of the CIP) this matter was presented at the International Electrical Congress in Turin, raising the proposition to broad the original scope of the CIP to include the work of light engineers along with the current work on photometry and standard unit creation for light and illumination.

The initial Statutes of the just recently created Commission Internationale de l’Eclairage were finished effectively in September 23 of 1913.

Today, the Commission is an independent, non-profit organization devoted to the worldwide cooperation for scientists and engineers to discuss and exchange information on matters relating to the science and art of light and lighting, colour and vision, photobiology and image technology.