A portable spectra detection system has been developed to enable reflection measurement. This system is mainly composed of spectrometer, LED source and five optical elements. The size of the optical system is about 126 mm × 72 mm × 30 mm. The system covers a range of 340 nm-820 nm, and the spectral resolution is 6.0 nm. Based on the detection system, two example applications for ripeness detection and real-finger identification are carried out to demonstrate the system performance. The detection time is less than 1 second, and a satisfactory agreement was observed between detection results and realistic situation.
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