| 摘要 |
An exit pupil extender with one input optical element and two exit optical elements disposed on different sides of the input optical element. The exit pupil extender also comprises two intermediate diffractive optical couplers, each disposed between the input optical element and one exit optical element. The couplers serve as exit pupil extending components. The grating lines of the couplers are at substantially a 60-degree angle from that of the optical elements in order to optimize the exit pupil extending efficiency. This invention further describes a general diffractive optics method that uses a plurality of diffractive elements on an optical substrate for expanding the exit pupil of a display of an electronic device for viewing. The system can support a broad range of rotations angles (e.g., 0<rho<70°) and corresponding conical angles and remains geometrically accurate. |
