We show experimental results from a prototype multiplexed imaging spectrometer. Spectral information is encoded via a dual-dispersive architecture using a digital micromirror spatial light modulator (SLM) and decoded on-chip at the focal plane with a computational imaging array. Light from the scene is dispersed through a first prism and imaged onto the SLM, which applies a unique time-varying binary (1,0) encoding to each spectral bin. The encoded light is then recombined through a second prism and imaged onto a computational imaging array, where the multiplexed image is decoded on-chip. The computational imaging array is comprised of a 32x32 array of pixels with the capability of acquiring eight concurrent measurements that can be modulated with a time-varying duo-binary signal (+1,-1,0) at MHz rates. This results in eight decoded images per frame at a maximum frame rate of 1600 frames per second. The frame rate of the system depends on the number of encoded spectral bins. At the high end it is limited by the switching speed of the DMD SLM, and at the low end it is limited by the readout rate of the imaging array. We explore these trades as well as discuss areas for future improvement.
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