| 摘要 |
An image display apparatus detects the position of a point on a screen opposed to a photosensor based on the average of the number of scanning lines displayed before detecting an electron beam in the first scanning direction by the photosensor, and based on the number of scanning lines displayed before detecting an electron beam in the second scanning direction by the photosensor. The point may further or alternately be detected using the average of a time required from the start of one horizontal line scanning operation to detection of the electron beam, by the photosensor, in the first scanning direction, and a time required from the start of another one horizontal line scanning operation to detection of the electron beam, by the photosensor, in the second scanning direction. |
