Wearable multi-sensor for plant monitoring, based on fluorescent fibers

The paper is mainly focused on assessing the local effects of climate change on biodiversity, especially within the conservation of native plant species, by using a wearable plant demonstrator for chlorophyll and growth rate monitoring. The wearable proof-of-concept is implemented with: a) blue fluorescent fiber and light diffusion fiber configuration, for chlorophyll monitoring and b) optical fiber bending measurements, proportional with growing rate of the leaf. The blue fluorescent fiber from the Industrial Optical Fiber-USA is used to monitor chlorophyll fluorescence (spectral analysis) under stimulated conditions produced with light diffusion fiber. Stimulated light is induced by the light coupled to the surface of the leaf to be analyzed, using the Corning Fibrance (LDF) light diffusion fiber. The blue fluorescent fiber-BFF (peak 460 nm) is lateral sensitive and the chlorophyll fluorescence spectrum is coupled to the fiber core. The LDF is placed on the leaf, near BFF. The chlorophyll fluorescence emission spectrum falls outside the absorption spectrum of the blue fluorophore of the doped fiber core BFF. The chlorophyll fluorescence will propagate along the fiber, adding a specific spectral response corresponding to the analyzed scenario. The spectral response reflects the change with the physiological state of the photosynthetic system.