Hi Stephen,
thanks for your interest,
You got the general idea, it is some kind of holographic projection, but restricted to the physical underlying model,
to make things clear i will post a part of my thesis plan, that will hopefully explain the basic problem:
"Augmented reality comprises a wide range of different applications, techniques and input/output
devices. In general it supplements the real environment with additional, virtual information.
The spatial augmented reality (SAR), visualizes the virtual content directly on the surface of physical
objects. The information can appear on arbitrary surfaces or aligned to real 3D objects. Users of this
system are unconstrained from hardware devices such as head-mounted-displays. Projection-based
spatial displays use front-projection to support multiple users indpendently. The virtual information is
presented on a wide field-of-view and in high resolution. The shader lamps technique illuminates
diffuse white objects with multiple projectors, simulating different surface appearances.
While interacting with a shader lamps system, users will be casting shadows on the object, destroying
the intended impression. Compensating these shadows with additional projectors will improve the
usability of projection-based spatial displays. The main goal of this thesis is to develop a prototypical
shadow elimination algorithm for shader lamps."
The following picture shows a shader lamps model:
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To reach this goal it is compulsory to detect the user shadow or the user shape !
Former approaches have used the infrared technique to distinguish the usershape from the surface of the model.
The algorithm works as follows:
Unlike the user, the surface is illuminated with (i suppose) near infrared waves! NIR cameras, record the high IR contrast between the IR unilluminated user and the IR illuminated surface. (This results in a deteted user shape and methods can be started to compensate the shadow on the surface...)
The following picture shows the infrared approach in a 2d environment:
I know that all surfaces reflect/emit IR waves, but the approach described above did work! Maybe it was limited to a specific waveband...
This approach could be enhanced if it is possible to detect the "normal" IR radiance emited by humans AND if this irradiance is recognisable by cameras in projector illuminated environment. Maybe it is considerable, that standard projectors filter out IR radiance...
A question concerning this might be whether the projector-illuminated model emits IR waves although it is not illuminated by IR light..?
However, the best solution would be an IR absorbing white material !!!