Abstract
Hyperspectral imaging systems used in plant science or agriculture often have suboptimal signal-to-noise ratio in the blue region (400–500 nm) of the electromagnetic spectrum. Typically there are two principal reasons for this effect, the low sensitivity of the imaging sensor and the low amount of light available from the illuminating source. In plant science, the blue region contains relevant information about the physiology and the health status of a plant. We report on the improvement in sensitivity of a hyperspectral imaging system in the blue region of the spectrum by using supplemental illumination provided by an array of high brightness light emitting diodes (LEDs) with an emission peak at 470 nm.
Highlights
IntroductionHyperspectral imaging is commonly used to study the characteristics of plants in a certain environment, or their reaction to abiotic (drought, nutrient deficits, heavy metals) or biotic (plant diseases, pests, weeds) stress at different scales, from remote to proximal sensing [1,2]
Hyperspectral imaging is commonly used to study the characteristics of plants in a certain environment, or their reaction to abiotic or biotic stress at different scales, from remote to proximal sensing [1,2]
Lighting, shows a high standard deviation in measured values at both extremes of the spectral range, i.e., in the [400–500] nm visible and 900–1000 nm near infrared regions. In these areas the measured standard deviation may represent greater than 10% of the measured signal for the white reference bar
Summary
Hyperspectral imaging is commonly used to study the characteristics of plants in a certain environment, or their reaction to abiotic (drought, nutrient deficits, heavy metals) or biotic (plant diseases, pests, weeds) stress at different scales, from remote to proximal sensing [1,2]. The visible spectrum (VIS, 400–700 nm) is mainly influenced by the absorbance of leaf pigments (chlorophylls, carotenoids, xanthophylls, and anthocyanins) [3,4], and many studies focus on the use of visible reflectance in plant science. The reflectance of light at blue wavelengths (400–500 nm) is often neglected due to technical limitations, despite relevant information on the optical properties of plants, such as absorbance maxima of chlorophyll a, chlorophyll b and ß-carotene being contained in this region of the electromagnetic spectrum. Changes in the composition of these pigments are a first indicator of plant stress and can be assessed by hyperspectral imaging [5] and, as a consequence, several vegetation indices, based on reflectance wavelength around 450 nm, have been introduced. The Plant Stress Index (PSR = R430/R680) or the Structure
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
