MULTI-MODE VISUAL DISPLAY USING RECONFIGURABLE HOLOGRAPHIC OPTICS

摘要

Visual display apparatus can enable viewing of a display screen in multiple modes that provide different ranges of acceptable viewing angle and/or viewing distances. For example, the visual display apparatus can enable viewing of a display screen in a public mode intended to accommodate viewing of the screen by multiple people (i.e., a mode affording a relatively wide range of acceptable viewing angles) or a private mode intended to accommodate viewing of the display screen by a single person (i.e., a mode affording a relatively narrow range of acceptable viewing angles). In one embodiment reconfigurable holographic optical elements (HOEs) are used to form a virtual image (615) for the private mode and a real image (614) for the public mode. The visual display apparatus is implemented as part of a portable computer and the use of reconfigurable HOE(s) enables the display screen to be made thinner and lighter.