*Microsoft is a place where great ideas go to die, but that's nevertheless rather interesting – holograms busting out of mobile screens.
"Abstract
"A projection-type display device is connectively coupled to a mobile device (such as a smartphone) where the light generated by a small projection device is directed at a relatively transparent holographic optical element (HOE) to provide a display to an operator of the mobile device or a viewer. The projector and HOE may be configured to produce and magnify a virtual image that is perceived as being displayed at a large distance from the operator who views the image through the HOE. The HOE may comprise a volume grating effective at only the narrow wavelengths of the projection device to maximize transparency while also maximizing the light reflected from the display projector to the eyes of the operator...."
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"SUMMARY
"[0003] Various implementations are directed to a projection-type display device that may be connectively coupled to a mobile device where the light generated by a small projection device is directed at a transparent holographic optical element (HOE) to provide a user display (i.e., a display to an operator of the mobile device, or a viewer). Depending on the implementation, the HOE may be transparent, partially transparent, or semi-transparent. In some implementations, the projector and the HOE may be configured to produce and magnify a virtual image that is perceived as being displayed at a large distance from the viewer of the image through the HOE (e.g., a human operator of the mobile device).
"[0004] In some implementations, the HOE may comprise a volume grating effective at only the narrow wavelengths of the projection device to maximize transparency while also maximizing the light reflected from the display projector to the human operator's eye.
"[0005] Some implementations may comprise "augmented reality" applications that produce a virtual image that, when projected at infinity, appears in the space beyond the mobile device and superimposed on the "real world" (as opposed to a real image in the plane of the display surface). For such implementations, the mobile device may be used with pointing and telestration applications including but not limited to use as a portable head-up display for an operator of the mobile device...."
