US Patent 9593982 Sensor-synchronized spectrally-structured-light imaging

A smartphone is adapted for use as an imaging spectrometer, by synchronized pulsing of different LED light sources as different image frames are captured by the phone's CMOS image sensor. A particular implementation employs the CIE color matching functions, and/or their orthogonally transformed functions, to enable direct chromaticity capture. A great variety of other features and arrangements are also detailed.