Patent ID: 7542197

Claim:
An image projection system comprising: a spatial light modulator supported on a device substrate for controlling a light modulation element further including a hinge disposed on said device substrate to support a mirror at a distance above said device substrate to reflect and modulate an incident light emitted from a light source; an antireflection structure comprising cyclic protrusions extended from a surface of said device substrate underneath said light modulating element wherein a distance between two of said cyclic protrusions is shorter than a wavelength of an incident light for preventing a reflection of said incident light from said antireflection structure; said cyclic protrusions having a cross sectional shape of substantially side-by-side vertical triangles; and said side-by-side triangles is characterized by: λ> P>λ/ 2, and H/W> 3, where the P is a pitch between top vertex points of the side-by-side triangles, the λ is the wavelength of the incident light, the H is the height of the side-by-side triangles, and the W is a base width of the side-by-side triangles.