X-Y viewport scroll using location of display with respect to a point

摘要

A large X-Y workspace, such as a table, serves as a support for a viewport flat panel display which moves over the surface of the table. The portion of the viewport display on the table determines the portion of information displayed on the viewport display. When the surface of the table is used as a backlit display, a low resolution image can be projected onto the surface of the table. The viewport display can then show selected information related to the underlying information it covers, such as high resolution views, infrared views and map information. Lifting a viewport off the table surface freezes the portion of the image on the screen. Images on one viewport can be transferred to another viewport.