We report on the Dispersion Leverage Coronagraph (DLC), a variation of the Achromatic Interfero Coronagraph (AIC) that is designed for optical systems featuring dispersive primary objectives that provide enhanced one-dimensional angular resolution. It was specifically designed for the Diffractive Interfero Coronagraph Exoplanet Resolver (DICER), a notional 20m class infrared space telescope utilizing the enhanced one-dimensional angular resolution of large diffraction gratings in order to discover and characterize near-Earth exoplanets. Here we develop the theoretical foundation for DLC, the interferometric system utilized by the DICER instrument for reduction of the exoplanet/host-star flux ratio. While the core method of operation of DLC remains very similar to AIC, the introduction of dispersive primaries alters the optical system in many nontrivial aspects. Here we derive important properties of the DLC system including focal plane transmission maps, stellar leakage, residual optical path difference tolerance, and pointing error/jitter considerations. Ultimately, we found that DLC effectively nulls a target spectrum across the entire focal plane, allows for 2D/λ diffraction limited imaging, and requires asymmetrical fine-guidance tolerances on pointing error/jitter.
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