Fenestraria aurantiaca (also known as window plant) is a succulent with specialized adaptations to deal with heat, light and aridity. Fenestraria aurantiaca (F. a.) grows with most of its body under the sand. Just the top, with a light transparent surface – the window – on it, protrudes from the surface hence giving explanation to the plants name. Experiments with light, and detailed microscopy studies show the physical, biological and chemical capabilities of F. a. It was found that the window works as a lens, light from a 90 ° angle is directed into the plant. Thereby the window filters the light. Up to 90 % of the visible light is blocked; with rising wavelength the window gets more transparent until the near infrared light (1000 nm) where the transparency declines rapidly. But the parenchyma is up 90 % transparent. Based on those results the principles of the plant were defined, which are used for abstractions. Generally F.a. has four principles: light handling, surface cleaning, heat avoidance and water storing. Improvements founded on the inspiration of the window plant seem to be possible in photovoltaic systems, which have problems with overheating and also light concentration. An example solution called “buried solar cells” is presented. Another working field is the screen of mobile devices, where the clarity and readability suffers from direct sunlight. With the help from the methods displayed by F.a., there is an energy saving solution explained.
Recognition of Banknote Fitness Based on a Fuzzy System Using Visible Light Reflection and Near-infrared Light Transmission Images
