 is in essence a sophisticated heat beam which we call a laser. Laser is actually an acronym that stands for light amplification by stimulated emission of radiation. A laser can measure the excited states of materials. Wait, let's back up. The word spectroscopy means measuring with light. And the interaction of light with matter is called photochemistry. We see photochemistry every day. Look at what happens to this blue t-shirt as it is left out in the sun for one week. Let's discuss the interaction of matter with light. Do you remember your color wheel? If we observe a material that looks yellow, that means it's absorbing most of the other colors in the wheel. And in most cases, it absorbs colors opposite to yellow. That means violet, blue, and red. Okay, let's translate what we've discussed from our color wheel to an optical spectrometer. Let's illustrate what a solution of red dye might look like for an optical absorbance measurement. The material is absorbing blue and green. We see red and orange reflected back. And these are monochromatic laser lines. So Dr. Watasenge, how does a laser provide a fast picture? Just like a strobe light or a speed camera. Here we have a very fast laser system. And in this instrument, we can excite our sample. And when the fluorescence decay can have various lifetimes. So using this fast laser and this instrument, we can measure these ultra-fast processes. So that is how the whole setup will do it. Enjoying a fast picture about the material or the fluorescence. Okay, and can you explain how your laser system relates to solar cells or solar energy? Well, first of all, whenever a material absorbs light, it's going to go into a high excited state. Then in order to use this material in solar energy technologies, we need to know what's happened when this material goes into the excited state. So if the lifetime is very fast, probably it's not very suitable for solar energy-related applications. So in order to measure that, we need a system like this where we can measure very fast processes like femtosecond processes or slow process, nanosecond, microsecond process. And this instrument is capable of measuring femtosecond and bosecond process. And if you want to measure slow process, we need to use other experimental techniques. Well, thank you very much. You're welcome. To reiterate, lasers can study the excited states of materials, which helps to improve the performance of solar panels.