Two separate diffractors are employed in a crossed configuration to achieve two‐dimensional spectral imaging. The crossed crystal concept is here generalized to apply to either Bragg case (surface) or Laue case (transmission) diffractors which may undergo either symmetric or asymmetric diffraction, and which may be crystals, pseudocrystals, or multilayers, and may be flat or curved. The crossed crystal spectrograph offers wide selection of 2dspacings, crystalRvalues, resolutions, polarization losses, wavelengths, and magnifications.