Projector system

A projector system that projects an image onto a projector screen by means of a projector, receives with an optical receiver an image of a laser pointer radiating onto the projector screen from a laser pen, and converts the position of the laser pointer on the received screen to a coordinate position on the projector screen using a two-dimensional projection conversion formula, and in addition, projects markers onto the projector screen in advance using the projector, and automatically generates the two-dimensional projection conversion formula by using the positions of the markers received by the optical receiver as well as the predetermined positions of markers on the projector screen, the projector system comprising:

• controlling means for causing the projector to project a guarantee marker in addition to the markers;
• detecting means for detecting the positions of candidates for the markers on the received screen, while allowing noise and the guarantee marker to be included in the marker candidates;
• conversion formula generating means for generating a provisional two-dimensional projection conversion formula using the positions of a predetermined number of candidates among the detected marker candidates, as well as the pre-determined positions of the markers on the projector screen;
• position converting means for using the provisional two-dimensional projection conversion formula thus created to convert the positions of the marker candidates that were not used by the conversion formula generating means to create a two-dimensional projection conversion formula into positions on the projector screen;
• and
• determining means for determining whether or not there exists a position among the converted positions that matches the pre-determined position of the guarantee marker on the projector screen, and thereby determining whether or not the provisional two-dimensional projection conversion formula generated by the conversion formula generating means is the true two-dimensional projection conversion formula that used the positions of markers on the received screen;
• wherein
• when a negative determination is obtained by the determining means, a different provisional two-dimensional projection conversion formula is generated by the conversion formula generating means by varying the marker candidates used by the conversion formula generating means to generate the two-dimensional projection conversion formula, until a positive determination is obtained, and wherein the provisional two-dimensional projection conversion formula at the time a positive determination is obtained by the determining means is taken to be the true two-dimensional projection conversion formula, and used to convert the position of the laser pointer.