UV TALK LETTER Vol. 17

All the various things we see with our eyes either generate or absorb light. The range of light detectable to the human eye is called visible light. Using our eyes as detectors, we routinely perform quantitative and qualitative analyses based on the colors we observe in our daily lives. Similarly, UV-VIS spectroscopy and fluorescence spectroscopy are used to accurately analyze light in both the visible and ultraviolet light ranges. Both photometric methods measure the same wavelength range, but they differ in the type of samples they can measure and their detection sensitivity, due to differences in instrument design. In this two-part series, we will describe both UV-VIS and fluorescence spectroscopy by comparing their characteristics, such as their operating principle, system composition, and advantages and disadvantages. In this first part, we will discuss the relationship between light absorption and fluorescence, the principle of fluorescence, and advantages of measuring fluorescence over absorption.