Young first demonstrated that he could generate any colors that could be In 1802, Thomas Young, an English physician who had a burning desire to understand the nature of light, made progress in solving this magenta puzzle.

Since magenta was a non-spectral color of light, its origins posed a mystery. Newton organized his findings in a color wheel showing the three 'primary colors' - red, green, and blue - separated by the three 'secondary colors' - yellow, cyan, and magenta. But when he combined red and blue light from his prisms, Newton observed a colored light, magenta, that was not found in the natural visible spectrum.

In both of these cases, Newton apparently regenerated light in another portion of the natural spectrum. Green and red light mixed to give yellow light. When he combined blue and green light, he observed light the color of cyan. When any two of these were combined, secondary colors were formed. Using prisms and mirrors, he discovered that when the light from three separate parts of his rainbow, the red, green, and blue regions, were recombined they would regenerate white light. Observed something no one else had because he extended the experiment. Was split into red, orange, yellow, green, cyan and blue light. When he held a prism of glass in the path of a beam of sunlight coming throughĪ hole in the blind of his darkened room, he observed that the white sunlight Newton had quarantined himself in his rooms to avoid the plague that was raging through England at the time. At the age of 23, Isaac Newton reinvestigated this same dispersion of white sunlight into a rainbow of colors. Thus a 'spectrum' of different colored lights that matched the rainbow was produced. Rays of red light were bent least and blue rays of light were bent most. He found that as the light was refracted by the water, the angle of refraction of separate rays of various components of the light were different. More importantly for our discussion of color, Al Hazen investigated the origins of the rainbow using glass spheres filled with water. This idea was adopted in the Renaissance by artists such as Brunellschi who developed the principles of perspective. When these rays entered the pupils of the eye, they are focused as the point of a visual cone. When this light hit an object the reflected rays carried its image to the viewer's eye. He developed an alternative theory in which light traveled in straight lines and that the light emanated from sources such as the sun or a candle instead of the viewer's eye. The 10th Century Arab scientist-philosopher Al Hazen found that the common view, the one one held in Europe, was preposterous. But Europe was far behind the Islamic World in scintific thought and technology. The common viewpoint passed down to European thinkers by medival times held that rays of came out of the viewer's eye, and when these rays hit an object, they would send back the image to the viewer's eye. We begin by asking, 'What happens when we see? What physics events are involved?' These are a ancient questions which philosophers such as Aristotle, Ptolemy and Galen tried to addressed. This technique can and will be used by us to look at a variety of pigments in egg tempera paints when we make color wheels in our class-wide experiment. Chemists can use this technique as a way of determining which compounds are present, as a way of investigating the structure of compounds that are present, or as a means to determine how much of a particular compound is present. Here we will pay particular attention to the wavelengths of light that have been removed from the overall spectrum by interaction with matter. Look briefly at spectroscopy, a means of looking at the variations of intensities in light of different wavelengths across the whole spectrum of visible light. Give one color while a second compound generates another color. Theory and then use this knowledge to explore why one chemical compound will For the purposes of this class we will look first at color Is useful for artists to understand how colors are formed as well as how theyĪre perceived. Color is one of the principle elements of the visual arts.

Primary colors of pigment