| 摘要 |
A light pen for use with a home or personal computer comprises an elongate housing 12 having a collimator 16 projecting from its tip, for contacting the screen of a monitor or television connected to the computer. The collimator directs light from the screen onto a photodiode 26 within the housing, to produce a first output signal in response to this light. Additionally, the collimator is movable longitudinally of the housing against the bias of a spring 32 and is connected to a switch, so that pressing the light pen against the screen causes the collimator to operate the swich to produce a second output signal. <IMAGE> |
