Display device for representing object e.g. human body in three-dimensional representation during training of medical operations, has image data-generating device for generating image data comprising image of object and image of mirror

The device has a screen (201) e.g. multi-touch screen, for displaying image data in a virtual reaction area (200). A manipulator (101) is arranged on the screen for executing movements in an interaction area (100) in front of the screen. A tracking device optically detects position and/or orientation of the manipulator in the interaction area. An image data-generating device generates image data, where the data comprises an image of an object, an image of a virtual mirror (206) i.e. concave mirror, and an image of the object reflected partially in the mirror. Independent claims are also included for the following: (1) a method for displaying an object on an image display device (2) a computer program for executing a method for displaying an object on an image display device.