Photo courtesy of the Color Group of the UK
John Guild was a British scientist who worked at the National Physical Laboratory (NPL) at Teddington in England. Guild spent the majority of his professional life making outstanding contributions to the development of a wide variety of optical instruments and techniques [1].
In the 1920s, he wrote several papers, published in the Transactions of the Optical Society, describing the fundamentals of colorimetry which have formed the basis of the discipline ever since.
64.1 Color-Matching Functions
He measured, for seven observers, additive matching results for the colors of the spectrum using beams of red, green, and blue light. This work, together with a similar study carried out by W. David Wright, with ten additional observers formed the basis of the international standard for measuring color, the CIE 1931 Standard Colorimetric Observer. The quality of this experimental work was so high that this standard, although now more than eighty years old, is still in wide use. Guild was largely responsible for making this work the basis of the international system of colorimetry that is still in use today. In collaboration with T. Smith, also of the NPL, he devised the transformation of the experimental results into the International Commission on Illumination (CIE) XYZ system that is the form in which the standard is used.
In spite of having played a key role in establishing the basis and original standard of colorimetry, after 1931 Guild transferred his interests to other areas of work and took little further part in the subject. However, he retained his interest in colorimetry and was instrumental in the formation of the Color Group in the UK where he was the second Chairman of the Group (1943–1945) and one of the first Honorary Members in 1966 [1].
J. Guild, An equipment for visual spectrophotometry. Trans. Opt. Soc., 26, 74–94 (1924–1925).
J. Guild, The transformation of trichromatic mixture data: algebraic methods. Trans. Opt. Soc., 26, 95–108 (1924–1925).
The geometrical solution to colour mixture problems. Trans. Opt. Soc., 26, 139–174 (1924).
J. Guild, A trichromatic colorimeter suitable for standardisation work. Trans. Opt. Soc., 27, 106–129 (1925–1926).
J. Guild, A criticism of the monochromatic-plus-white method of colorimetry. Trans. Opt. Soc., 27, 130–138 (1925).
J. Guild, On a new method of colorimetry. Trans. Opt. Soc., 27, 139–160 (1925–26).
T. Smith and J. Guild, The CIE colorimetric standards and their use. Trans. Opt. Soc., 33, 73–134 (1931–32).
J. Guild, The colorimetric properties of the spectrum, Phil. Trans. Roy. Soc. (London) A, 230, 149–187 (1931).