Patent ID: 7102634

Claim:
An apparatus for displaying a three-dimensional virtual endoscopic image, the apparatus comprising: a volume data input unit being configured to input information on a virtual endoscopic image in the form of volume data expressed as a function of three-dimensional position; a two-dimensional reference image display control unit being configured to derive a two-dimensional reference image from the volume data and displays the two-dimensional reference image; a three-dimensional reference image display control unit being configured to derive a three-dimensional reference image from the volume data using parallel volume rendering and displays the three-dimensional reference image; a virtual endoscopic image display control unit being configured to apply position and direction information of a virtual camera used to collect virtual endoscopic image information to a predetermined perspective ray-casting algorithm to generate image information, and to display a virtual endoscopic image based on the generated image information, the virtual camera being configured to display a sphere having a predetermined radius from a current position of the virtual camera on the two-dimensional reference image as the camera display sphere and to display a set of intersection points between the camera display sphere and the two-dimensional reference image as the camera display circle, and to display a sphere having a predetermined radius from the current position of the virtual camera on the three-dimensional reference image as the camera display sphere and to display a set of intersection points between the camera display sphere and a plane passing the current position of the virtual camera displayed on the three-dimensional reference image and being parallel with the screen as the camera display circle, and the virtual camera being configured to assume that there is an infinite ray in the direction of each virtual camera, to detect an intersection point between the infinite ray and a corresponding camera display sphere, and to represent the direction of the virtual camera with an arrow starting from the center of the virtual camera and passing the intersection point, and to set a corresponding camera display circle and the virtual camera to have different colors when the virtual camera faces the surface of a hemisphere in front of an image and when the virtual camera faces the surface of a hemisphere in the rear of the imgae; a user interface unit being configured to receive a user's operating signal; and a controller being configured to control the two- and three-dimensional reference image display control units and the virtual endoscopic image display control unit to be associated with one another based on the operating signal when the operating signal to change image information displayed by one among the two-dimensional reference image display control unit, the three-dimensional reference image display control unit, and the virtual endoscopic image display control unit is input through the user interface unit.