| 摘要 |
An apparatus is described for assessing plant chlorophyll content remotely sensed by the invention thereby allowing selective monitoring or treatment of individual plants. In one preferred embodiment, a polychromatic emitter provides light beams substantially in the red edge portion of a plant's reflectance spectrum. This light beam illuminates a surface area on the plant, which may be bare ground or plants. The beam of light may be focused, collimated or non-focused. A detector array, usually composed of an array of spectrally sensitive detectors, detects portions of this polychromatic light beam reflected by the surface area and provides a signal indicative of the change in chlorophyll status by determining the wavelength of the red edge inflection point REIP. In another preferred embodiment of the invention, an array of sequentially pulsed monochromatic emitters provides light beams having wavelengths substantially along the red edge portion of a plant's reflectance spectrum. These light beams illuminate a surface area on the plant, which may be bare ground or plants. The beams of light may be focused, collimated or non-focused. A photodetector detects the light reflected by the surface area and provides a signal indicative of the change in chlorophyll status by determining the wavelength of the red edge inflection point REIP. In both embodiments, a controller analyzes the resulting REIP wavelength and responds by activating a device to take some action with respect to the plant or stores the analyzed signal with corresponding DGPS position in the controller's memory for later analysis. |
