| 摘要 |
A light beam is used to illuminate a spot on a lens element which is shifted along the optical axis of an imaging system for auto-focus or optical zoom purposes. The light beam is arranged such that the reflected light beam from the lens element encounters a spot on the image sensor. The spot location on the image sensor is determined by a signal processor. As the lens element is shifted along the optical axis, the spot location changes accordingly. Based on the moving distance of the spot, the signal processor determines the shifting distance of the lens element and hence the position of the lens element. Based on the shifting distance of the lens element, a control module is used to adjust the lens position along the optical axis to achieve the desired focusing or zooming effects. |
