  For the first time, a CAOS (i.e., Coded Access Optical Sensor) spectrometer
is demonstrated. The design implemented uses a reflective diffraction grating
and a time-frequency CAOS mode operations Digital Micromirror Device (DMD) in
combination with a large area point photo-detector to enable highly
programmable linear High Dynamic Range (HDR) spectrometry. Experiments are
conducted with a 2850 K color temperature light bulb source and visible band
color bandpass and high-pass filters as well as neutral density (ND)
attenuation filters. A ~369 nm to ~715 nm input light source spectrum is
measured with a designed ~1 nm spectral resolution. Using the optical filters
and different CAOS modes, namely, Code Division Multiple Access (CDMA),
Frequency Modulation (FM)-CDMA and FM-Time Division Multiple Access (TDMA)
modes, measured are improving spectrometer linear dynamic ranges of 28 dB, 50
dB, and 96.2 dB, respectively. Applications for the linear HDR CAOS
spectrometer includes materials inspection in biomedicine, foods, forensics,
and pharmaceuticals.

Signal Processing;Optics