Patent ID: 7220008

Claim:
A reflective display device comprising a retroreflective layer including a plurality of unit structures that are arranged two-dimensionally on a virtual plane, and a modulating layer, which is arranged closer to a viewer than the retroreflective layer is and which is switchable between a first state and a second state that have mutually different optical properties, the reflective display device conducting a display operation by using light that has been reflected back from the retroreflective layer, wherein each said unit structure of the retroreflective layer has a recess defined by three planes that are opposed substantially perpendicularly to each other, the unit structures being arranged so as to face substantially the same direction, and wherein an azimuthal direction, which is defined by projecting a normal to one of the three planes onto the virtual plane, and another azimuthal direction, which is defined by projecting an on-screen downward direction onto the virtual plane, form an angle of less than 30 degrees.