Volume holographic diffusers

A method of projecting diffuse light from a display (1) to a predetermined viewer head box location (100) comprising the steps of;

• sending a group of collimated or partially collimated light beams through a substrate matrix (30) comprised of a plurality of nested individual joined geometrically shaped cells (301) wherein each of the cells contains a patterned volume holographic diffuser, and
• producing from each of the cells a transmitted diffused light beam (305),
• said method being further characterized in that;
• said method projects diffuse light from the display to the predetermined viewer headbox location producing a uniform resultant luminance over a wide range of view angles with a predetermined beam spread and beam deflection angle at said predetermined viewer head box location,
• said method comprising the steps of:
• projecting said transmitted diffused light beam light from each of said cells (301) in a unique direction diverse from each other of said cells;
• limiting said transmitted diffused light beam light to a narrow angular luminance distribution profile curve (80) with sharply vertical profile slopes (81) at halfpeak points (20);
• and
• superimposing each transmitted diffused light beam from each of the cells to form a combined resultant diffused light beam having an angular luminance distribution profile curve (83) with sharply vertical profile slopes at halfpeak points and with a substantially flat and wide peak (84).