  We present a novel type of Suppressed-Order Diffraction Grating(SODG). An
SODG is a diffraction grating whose diffraction orders have all been suppressed
except one that is selected to provide electromagnetic deflection. The proposed
SODG is a transmissive grating that exhibits high-efficiency refraction-like
deflection for all angles, including large angles that are generally
challenging to achieve, while featuring a deeply subwavelength thickness, as
required in the microwave regime. We first present the design rationale and
guidelines, and next demonstrate such a 10.5 GHz SODG that reaches an
efficiency of 90% at 70 degrees.
