引言自从牛頓在1666年發現了白光通过玻璃稜鏡可以分解為各种色光之後,在以後一百多年中,光谱的研究可以說是没有什么發展。1800年英国天文學家赫謝耳(1738—1822)曾由下述的实验发現红外線。他將一根灵敏的泡塗墨的温度計放到太陽光譜的紅端,观察到温度稍為上升;当他把温度計移動到紅端之外的区域時,則發現温度上升更高。这一实驗事实証明在紅色光之外还有為眼睛所不能感觉到的輻射存在。这种存在於太陽光譜紅端之外的輻射叫做红外線,或热射線。在十九世紀的初期,紅外線雖然已被發現,但是它的進一步的發展,却是在十九世紀 INTRODUCTION Ever since Newton discovered in 1666 that white light can be decomposed into various shades of light through glass prisms, the development of spectroscopy can be said to have been less developed for more than a century. In 1800, British astronomer Hersheel (1738-1822) discovered the infrared ray by the following experiment. He placed a sensitive, soaked thermometer on the red side of the solar spectrum and observed a slight increase in temperature. When he moved the thermometer to areas outside the red end, he found the temperature increased even more. This experimental fact proves that there is radiation outside the red light that the eye can not feel. This kind of radiation that exists outside the red end of the solar spectrum is called infrared light or heat rays. In the early nineteenth century, although the infrared has been found, but its further development, but in the nineteenth century