Patent ID: 6943950

Claim:
A method for operating a micromechanical grating, said method comprising: providing a micromechanical grating having a two dimensional array of deflectable elements, each element operable to tilt about an axis to a tilt angle and spaced apart from adjacent elements by a grating pitch; selecting a wavelength (λ) of near monochromatic spatially coherent light; selecting an angle of incidence and a diffraction order satisfying: θ t (θ i ,n )=½{arc sin[( nλ/d )√{square root over (2)}−sin(θ i )]+θ i } where: θ t is a tilt angle relative to said micromechanical grating normal, θ i is an angle of incidence relative to said micromechanical grating normal, n is a diffraction order, λ is a wavelength of incident near monochromatic spatially coherent light, and d is a pixel grating pitch of said micromechanical grating; and wherein a center of a Fraunhofer envelope is aligned with said n th diffraction order.