Patents: Cheap Trick

Simulations are normally made by forming a wireframe image of objects on a computer screen and then filling them in with computer graphics to make them look real. But making a realistic car dashboard or aircraft flight deck requires massive computing power if the image is to change at a reasonably fast rate.

Sony's answer is to split the workload. A computer work-station and video projector produce a two-dimensional image of the dashboard on a screen.

Separately a video effects generator, similar to those used to create special effects in TV programmes, projects moving picture images onto windows in the dashboard image which match the position of the vehicle's windscreen.

The effects generator draws from a library of basic pictures, for instance of roads and scenery, which are stored on disc or tape. It only needs to change the perspective: as an oncoming car approaches, the effects generator zooms into a library picture to make the vehicle appear to get closer. As soon as the car has passed, the generator selects an image of a lorry and starts working with that in the same way.

In this way, the simulator can deliver high-resolution pictures, which move smoothly, without expensive computer power. CDs that record and play