Just found this very interesting simple-ish NIR spectroscopic fingerprinting sensor which goes in the general direction of the Optical Inch. Same class of device although the impelementation is quite different because it uses dielectric narrowband filters.
"The AS7263 is a digital 6-channel spectrometer for spectral identification in the near IR (NIR) light wavelengths. AS7263 consists of 6 independent optical filters whose spectral response is defined in the NIR wavelengths from approximately 600nm to 870nm with full-width half-max (FWHM) of 20nm.
An integrated LED driver with programmable current is provided for electronic shutter applications.
The AS7263 integrates Gaussian filters into standard CMOS silicon via Nano-optic deposited interference filter technology and is packaged an LGA package that provides a built in aperture to control the light entering the sensor array. Control and Spectral data access is implemented through either
the I²C register set, or with a high level AT Spectral Command set via a serial UART."