About the Photo Experiment Connect the anodes and cathodes of the cyan-green LED and the green LED to each other, respectively. When the blue LED shines on the cyan-green LED, the green LED lights up brightly. About the Phenomenon LEDs are made of PN junctions. Photovoltaic cells are also made of PN junctions, just like LEDs. Therefore, if you shine light on an LED, it will generate electricity. However, when I tried the experiment, the light emission was weak and not very interesting. I experimented with several LEDs and light sources. This kit is a combination that became brighter. Please refer to the photos. The product is the second photo, which includes a blue LED pointer, a cyan-green LED, a green LED, and a breadboard.