Light valve projection system with off axis raster orientation

Light valve projection apparatus including electron beam means forming a raster of orthogonally related diffraction gratings on a light modulating fluid to diffract incident light for projection onto a viewing surface, comprising:

• a housing providing a sump for said fluid,
• a disk rotatably mounted within said housing so as to rotate about its center, said disk having a portion immersed in said sump so that said fluid coats the nonimmersed portion of at least one surface of said disk upon rotation thereof,
• means for directing said electron beam means to form on the fluid coating of said disk a raster of deposited charge along parallel scanning lines in a first direction to form a first set of diffraction gratings and at least a second set of diffraction gratings orthogonal to said first set,
• said means for directing said electron beam means causing said raster to be positioned on the nonimmersed portion of said disk between the offset from horizontal and vertical coordinate axes in the plane of said disk, said coordinate axes intersecting at the rotational center of said disk so as to divide said nonimmersed portion into first and second quadrants, said first set of diffraction gratings being substantially parallel to said horizontal coordinate axis,
• whereby the concentric generally circular paths traced by elemental portions of said fluid as said disk rotates intersect each of said sets of diffraction gratings and are not tangent to any of said sets of diffraction gratings.