Two LEDs perform rudimentary spectral analysisThis circuit use to measurement the different wavelengths of a pair of LEDs to stimulus for a rudimentary spectral analysis during quality-control sorting operations. By measuring the reflectance of each LED which can provide information about the spectral response of the object under test. The circuit’s operation is akin to the human eye’s using three receptors to deduce information about the entire visible spectrum.

Two LEDs perform rudimentary spectral analysis
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Two LEDs perform rudimentary spectral analysis