VIRTUAL RETINAL DISPLAY WITH EXPANDED EXIT PUPIL

摘要

A display device (10) is achieved using an optical system which generates an expanded exit pupil (21) without compromising magnification or resolution. Modulated light from a source (12) is converged toward a focal point by an optics subsystem (14). A scanning subsystem (16) deflects the converging light, and thus the focal point, along a raster pattern to define a curved intermediate image plane (15). An exit pupil expanding apparatus (18) defines a curved surface which coincides with the curved image plane (15). Impinging light rays at a given instant in time span a given incidence angle ( theta i). Exiting light rays span a larger angle ( theta o). The exiting light spans a larger surface area of an ensuing eyepiece (20). In turn an expanded exit pupil (21) occurs beyond the eyepiece. Exit pupil expanding embodiments include a curved diffractive optical element (300), fiber optic face plate (320), lens array (340) and diffuser (360). The diffractive optical element generates multiple exit pupils (304-316), while the other embodiments generate enlarged exit pupils.