A medical system has at least one projection surface onto which a projection unit projects of operating elements. The system is controlled by detecting movements of a hand, preferably a finger, of an operator on the projection surface. An optical detector acquires the position and/or the motion of the finger relative to the projection surface, and a control unit evaluates the output data of the detector in order to control the system.

In a video projector, first and second light sources respectively emit first and second collimated, white light beam, a luminance optical modulation means modulates the first light beam in accordance with a luminance signal of an input video signal, a chrominance optical modulation means modulates the second light beam in accordance with a chrominance signal of the input video signal, a first projecting means projects the first light beam having been modulated by the luminance optical modulation means onto a projection screen to form a projected luminance image on the screen, and a second projecting means projects the second light beam having been modulated by the chrominance optical modulation means onto the projection screen to form a projected chrominance image on the screen. The projected luminance image and the projected chrominance image are superimposed with each other on the screen to form a full color image.

A method and apparatus for painting 3-D objects and producing computer-assisted animated films are disclosed. After a 3-D model of an object is generated, a view of the object is selected for painting. An artist applies brush strokes to paint the selected view in 2-D space. The brush strokes are mapped to generate 3-D brush strokes. These 3-D brush strokes are then projected onto the 2-D views in the animation sequence, generating projected 2-D brush strokes which are used to paint the views in the animation sequence. Additional views may be selected that reveal surfaces that were occluded in the previously selected view. The artist applies additional brush strokes to paint the previously occluded areas. These additional brush strokes are mapped, and are used with the original brush strokes to re-generate the painted views in the animation sequence. A pixel color of a brush stroke may be determined based on the size, color, degree of opacity, degree of softness, pen pressures, pixel location, and brush profile. If brush strokes are leaf strokes, they are displaced by random amounts and rotated to random angles. A selective focus may be used to emphasize certain areas and de-emphasize others. Overlapping brush strokes may be painted in painter's order, depth order, or a blended combination of the two to allow a smooth transition between them. 2-D brush strokes can be blended to support build up and can be scaled to arbitrary size without pixel artifacts.

A system and method for precisely superimposing images of computer models in three-dimensional space to a corresponding physical object in physical space. The system includes a computer for producing a computer model of a three-dimensional object. A projector means projects an image of the computer model onto the physical object. A spatial transformation accurately maps the computer model onto a projection stage at the projector which projects a formed image in a three-dimensional space onto the physical object in a one-to-one correspondence.

The invention relates to a manually controlled input device for a computer which comprises a [graph] graphics card for controlling a monitor video screen [by means of] via a video signal, as a simulation and [in the form] of a mechanical small-size spraying device (air brush) whose operating parameters are composed of three space coordinates, the air pressure of the ink spraying jet and the ink quantity therein. Synchronization signals from the video card are used in conjunction with an optical coupling between the input device and the video screen, to determine the spacial coordinates of the input device relative to the video screen.