Surface light source capable of varying angular range for diffusing emitted light and liquid crystal display apparatus capable of displaying selectively with wide view angle and narrow view angle by using same

摘要

A liquid crystal display apparatus comprises first and second light emitting sections for emitting light with respective spreading angles that are different from each other and a liquid crystal display device arranged at the viewing side of the apparatus. The first light emitting section includes a first light guide plate for receiving light from a light incident end surface and diffusing it within a first angular range of spreading angle centered at the normal direction of a light emitting surface before emitting it from the light emitting surface and first light emitting elements. The second light emitting section includes a second light guide plate for receiving light from a light incident end surface and emitting it in directions within a second angular range of spreading angle smaller than the first angular range while transmitting light emitted from the first light guide plate and second light emitting elements.