Light pen and presentation system having the same

A presentation system comprising:

• a material presentation apparatus;
• and
• a light pen,
• the material presentation apparatus comprising:
• a material mounting pedestal having a mounting surface on which a material is mounted and a virtual screen is virtually generated;
• a photographing section supported on the material mounting pedestal via a support member and for photographing the material;
• an image output section for outputting an image photographed by the photographing section to a display device;
• and
• a control section for executing image processing, the light pen comprising:
• a rod-like body portion;
• a leading end portion removably mounted to the body;
• an emitter for emitting light on the virtual screen generated by the material presentation apparatus;
• and
• a switch for turning the emitter to ON and OFF, the emitter and the switch being provided at the leading end portion,
• wherein the emitter of the light pen emits light on the virtual screen, the emitter is photographed by the photographing section, the control section into which the image photographed by the photographing section is input calculates coordinates of the position of the emitter and executes a predetermined pointing function at the coordinates on an image on the display device, corresponding to the calculated coordinates of the emitter on the virtual screen.