A liquid crystal display apparatus which have a circular polarizer and a liquid crystal display in a stack. The liquid crystal display has a chilral nematic liquid crystal layer between substrates, and on the mutually opposite sides of the substrates, electrodes and aligning layers are formed. The liquid crystal switches between a planar alignment state and a focal-conic alignment state depending on the voltage applied thereto through the electrodes. In a planar state, light reflected by the electrodes is absorbed by the circular polarizer, and a black display is made. In a focal-conic state, light reflected by the electrodes passes through the circular polarizer, and a white display is made. The liquid crystal is driven by a chain of voltage pulses including a reset step of resetting the liquid crystal to a homeotropic state, a selection step of selecting the alignment state of the liquid crystal under zero-volt application and an evolution step of causing the liquid crystal to evolve to the selected alignment state.

 
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> Position and orientation sensing with a projector

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