| 摘要 |
PURPOSE:To provide a single-focus lens of simple and inexpensive constitution with a zooming function by putting one block in linear motion by the rotation of a rotating member supported pivotally on either of a lens block and an image pickup element. CONSTITUTION:The lens block 1 and a block 2 which holds the image pickup element 5 slide on two parallel shafts 3 and 4. When the block 2 is moved to left so that an object image distance is shortened and image pickup power is increased, a disk member 6 swivels clockwise by a linear cam groove 12a and a driving pin and a pin 10 moves to left to increase the interval between the blocks 1 and 2. Light transmitted through a film 13a is image-formed on the image pickup element 5 and zooming and focusing are performed associatively as long as the angle of the groove 12a and the precision of linearity are obtained without using any expensive zoom lens to perform high- precision focusing with the simple constitution. Further, a slight error in the position relation between a lens L and the element 5 is adjusted by a helicoid H. |
