An improved microchip spectrophotometer device (101) having a wavelength-sensitive light detector sensor (155) located on a microchip (241) that detects returning broadband light (128) that is narrow-spectrum wavelength filtered by gratings or filtered, such as through an optical collection window (141) on the sensor (155). Optionally, at least a portion of the returning broadband light was produced by one or more solid-state light sources (103, 103A, 103B) incorporated into the microchip device. Multispectral spectroscopic data from the detector is optionally transmitted such as by wire (161), then analyzed by a processor such as a difference unit (167), located on the same microchip or on a processing microchip. Systems incorporating the improved microchip spectrometer, and methods of use are also disclosed.
