text: It was not until 1666 that Isaac Newton showed that white lights from the sun could be dissipated into a continuous series of colors. So Newton introduced the concept which he called spectrum to describe this phenomenon. He used a small aperture to define the beam of light, a lens to collimate it, a glass prism to disperse it, and a screen to display the resulting spectrum. Newtons analysis of light was the beginning of the science of  Later, It became clear that the Suns radiation might have components outside the visible portion of the spectrum. In 1800 William Hershel showed that the suns radiation extended into [https://www.livescience.com/50260-infrared-radiation.html ], and in 1801 John Wilhelm Ritter also made a similar observation in the . Joseph Von Fraunhofer extended Newtons discovery by observing the suns spectrum when sufficiently dispersed was blocked by a fine dark lines now known as   Fraunhofer also developed  which disperses the lights in much the same way as does a glass prism but with some advantages. the grating applied interference of lights to produce  provides a direct measuring of wavelengths of diffracted beams. So by extending Thomas Youngs study which demonstrated that a light beam passes slit emerges in patterns of light and dark edges Fraunhofer was able to directly measure the wavelengths of spectral lines. However, despite his enormous achievements, Fraunhofer was unable to understand the origins of the special line in which he observed. It was not until 33 years after his passing that Gustav Kirchhoff established that each element and compound has its unique spectrum and that by studying the spectrum of an unknown source, one could determine its chemical compositions, and with these advancements, spectroscopy became a truly scientific method of analyzing the structures of chemical compounds. Therefore, by recognizing that each atom and molecule has its spectrum Kirchhoff and Robert Bunsen established spectroscopy as a scientific tool for probing atomic and molecular structures and founded the field of spectrochemical analysis for analyzing the composition of materials.