| 摘要 |
<p>A lens selection device for placing any one of three or more magnification lenses in an operative position where its optical axis aligns with a respective reference axis, a selected lens being shifted along a fixed path from a retracted position to the operative position thereof by separate drive means numbering one less than the quantity of the lenses. In the case of three lenses, for instance, a first drive means is used to shift a first lens, a second drive means is used to shift a second lens, and a follower means coupled with a third lens is used to shift it to its operative position when the first (or the second) lens is driven to its retracted position.</p> |
