| 摘要 |
An optical zoom system has two prisms to form an optical path loop for increasing the optical pathlength in a small device. The optical path loop is effectively introduced into the light path of the image sensor. The prisms are arranged such that the optical paths bounded by the internal reflecting surfaces form a rectangular loop. A reflecting module is inserted in the optical loop to direct the incoming light beam into the loop, and to direct the light beam exiting the other prism toward an image sensor for image formation. As such, a zooming lens group and a focusing lens group can be inserted into the loop to carry out the zooming and focusing functions. Both prisms are mechanically coupled to a single lead screw having a right-hand thread section and a left-hand thread section so that the prisms can be moved in opposite directions
|
