Overview
The publication of Opticks represented a major contribution to science, different from but in some ways rivaling the Principia. Opticks is largely a record of experiments and the deductions made from them, covering a wide range of topics in what was later to be known as physical optics. That is, this work is not a geometric discussion of catoptrics or dioptrics, the traditional subjects of reflection of light by mirrors of different shapes and the exploration of how light is "bent" as it passes from one medium, such as air, into another, such as water or glass. Rather, the Opticks is a study of the nature of light and colour and the various phenomena of diffraction, which Newton called the "inflexion" of light.
In this book Newton sets forth in full his experiments, first reported in 1672, on dispersion, or the separation of light into a spectrum of its component colours. He shows how colours arise from selective absorption, reflection, or transmission of the various component parts of the incident light. His experiments on these subjects and on the problems of diffraction (which he never fully mastered) set the subject of optics on a new level.
Newton's contribution to prismatic dispersion was remarkable since he outlined qualitatively multiple-prism configurations. Multiple-prism arrays, as beam expanders, became central to the design of the tunable laser more than 275 years later thus encouraging the development of the multiple-prism dispersion theory.
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