案例二: 上升流/下降流
2019/08/07
Sample Setup: Upwelling / Downwelling
Overview
Upwelling radiation is radiation -- either reflected solar or emitted terrestrial -- that is directed upward from the earth's surface. Downwelling radiation is radiation that is directed toward the earth's surface from the sun or atmosphere. The relationship between the two (albedo) can be used to derive spectral information from vegetation, forest canopies, seabeds and more.
Spectrometer
An HR4000 Spectrometer with an HC-1 grating provides an elegant solution for upwelling and downwelling measurements. The HC-1 is a variable-blazed grating that covers the 200-1050 nm wavelength range; optical resolution is ~1.5 nm (FWHM) with a 50 m slit as the entrance aperture. An OFLV-200-1100 Order-sorting Filter eliminates second- and third-order effects.
Sampling Optics
he spectrometer connects to a patch cord that screws into the CC-3-UV Cosine Corrector. The CC-3-UV can be used as part of a configuration for measuring absolute spectral irradiance. Youll need a DH2000-CAL (or LS-1-CAL for 300-1050 nm only) to calibrate the absolute spectral response of the system and SpectraSuite Spectroscopy Operating Software to calculate spectral intensity and photopic data in lumens, lux or candela. An alternative to the CC-3-UV is a Gershun tube, which has fixtures for adjusting the area of light from 1?to 28?and attaches directly to the spectrometer or to an optical fiber.