On-chip spectrometer using vertical hetero structure of long pass optical filters and silicon films Yu Wang, Bedabrata Pain, Tom Cunningham and Xinyu Zheng 1. Novelty This art describes a ultra-lightweight, on-chip spectrometer capable of multi- wavelength imaging with high efficiency and narrow bandwidth. Development of this capability directly relates to all current and future NASA efforts relevant to the multi-spectrum imaging and hyper-spectrum imaging for both remote sensing and in situ missions.